The biochemical response of Coffea arabica var.Borbon to chitosan and chitosan oligosaccharides(COS)was evaluated in one-year-old plants under greenhouse conditions.COS solutions were synthesized through chemical and ...The biochemical response of Coffea arabica var.Borbon to chitosan and chitosan oligosaccharides(COS)was evaluated in one-year-old plants under greenhouse conditions.COS solutions were synthesized through chemical and physical hydrolysis using acetic acid,hydrogen peroxide,and microwave irradiation.The obtained COS had an average molecular weight(Mw)of 3549.90±0.33 Daltons(Da),a deacetylation degree(DD)of 76.64±1.12%,and a polymerization degree(PD)of 18.91±0.0018.Solutions of chitosan and COS were applied to C.arabica var.Borbon at concentrations of 0.25,0.5,and 1 wt%.The experimental design was conducted using a completely randomized design with four replications.The biochemical responses assessed included soluble protein content,phenylalanine ammonia-lyase(PAL),chitinase,β-1,3-glucanase,peroxidase,catalase,and chlorophyll fluorescence.The application of COS demonstrated significant differences(α=0.05)in protein concentration,with the activity ofβ-1,3-glucanase,chitinase,and catalase being 1.5,7.5,and 3.9 times higher,respectively,while showing similar behavior to chitosan in PAL activity,both up to 4.4 times higher than the distilled water control and lower than chitosan in peroxidase activity.Treatments with chitosan yielded a higher photochemical efficiency of Photosystem II(PSII).The application of COS suggests a viable foliar alternative to active plant defense mechanisms without the risk of phytotoxicity.展开更多
Exogenous proline is an effective agent for increasing plant tolerance to abiotic stress in plants. In this study, we evaluated its effect on seedlings of Siete Caldos chili pepper (Capsicum frutescens), a semi-domest...Exogenous proline is an effective agent for increasing plant tolerance to abiotic stress in plants. In this study, we evaluated its effect on seedlings of Siete Caldos chili pepper (Capsicum frutescens), a semi-domesticated variety. The Capsicum genus is known for its sensitivity to water stress. We pretreated the seedlings’ roots by immersing them in proline solutions (0, 2.5, 5, 7.5, and 10 mM) for 48 h. Then, we exposed them to water stress using a Hoagland nutrient solution supplemented with 10% polyethylene glycol (PEG-8000) for nine days. We analyzed key physiological and biochemical parameters, including relative water content, cell membrane stability index, electrolyte leakage, chlorophyll, and proline content. The results indicated that proline concentrations of 2.5 and 5 mM significantly increased tolerance to water stress, with 100% survival. These seedlings maintained greater hydration and cell membrane stability compared to non-pretreated seedlings. In contrast, at the highest concentrations (7.5 and 10 mM Pro), survival was 63.63% and 54.54%, respectively. This study demonstrated that exogenous proline enhances water stress tolerance in Capsicum frutescens seedlings by mitigating the negative impact on physiological and biochemical processes vital for survival. This theoretical foundation can be applied to improve chili seedling performance in controlled production environments.展开更多
A significant portion of losses in the fruit and vegetable sector are caused by the necrotrophic fungus Botrytis cinerea,due to its high prevalence in over 1000 crop species.Identifying a technology capable of exclusi...A significant portion of losses in the fruit and vegetable sector are caused by the necrotrophic fungus Botrytis cinerea,due to its high prevalence in over 1000 crop species.Identifying a technology capable of exclusively inhibiting its growth and development remains challenging;therefore,various treatments have been proposed to act synergistically in preventing the spread of this pathogen.The objective of this study was to evaluate an ultrasound-assisted treatment combined with chitosan to control the development of B.cinerea.In vitro analyses showed that combining temperature,ultrasound,and chitosan inhibited the fungal radial growth by 80%,reduced sporulation,and decreased germination.Electrolyte leak analysis indicated damage to the B.cinerea cell wall,causing intracellular material to escape into the environment.Scanning and transmission electron microscopy images also revealed severe structural damage,including loss of the cytoplasmic membrane and cell lysis.展开更多
A geostatistical study was conducted with the objective of developing a better understanding of the sediments deposited in the tailings dam of an iron mine located in Brazil.The samples,derived from two drilling campa...A geostatistical study was conducted with the objective of developing a better understanding of the sediments deposited in the tailings dam of an iron mine located in Brazil.The samples,derived from two drilling campaigns conducted in 2001 and 2010,were statistically evaluated and validated for the construction of both a 3D geological model and an estimated model.The geological body modeling process was performed using an implicit method,which was based on the interpretation and adjustments of vertical sections and considered the positions of the samples and the grades of the chemical components of interest.In addition,the primitive topography was also considered to determine the base and limits of the deposit,as well as the current topography.The ordinary kriging(OK)method was chosen to estimate the grades of the chemical components and the retained/passing percentages of the particle size fractions described in the samples.The kriging model was validated through two analyses:mean comparison and drift analyses.The total tonnage of the estimated model was 287.14 Mt,with an average Fe grade of 63.89%.展开更多
Corn(Zea mays L.)is a very sensitive crop to phosphorus(P)deficiency during the early development phase,which may be a limiting factor for the sustainable production of this crop in P-deficient tropical soils.However,...Corn(Zea mays L.)is a very sensitive crop to phosphorus(P)deficiency during the early development phase,which may be a limiting factor for the sustainable production of this crop in P-deficient tropical soils.However,scientific evidence indicates that inoculation with phosphate-solubilizing bacteria can improve the development,uptake,and P-use efficiency of corn plants.In the present study,two contrasting corn hybrids were investigated for their responsiveness to multiple inoculations of Bacillus subtilis,B.megaterium,B.velezencis,and Pseudomonas fluorescens and application of phosphate fertilizer rates in the sandy soil of the Brazilian Cerrado.Plants from stable(DKB 360 PRO3)and responsive(DKB 255 PRO3)corn hybrids were inoculated with 0 and 2 mL of inoculant containing multiple phosphate-solubilizing bacteria and fertilized with low(0 mg P·kg^(-1)),medium(40 mg P·kg^(-1))and high(80 mg P·kg^(-1))levels of phosphate fertilizer using triple superphosphate(46% of P_(2)O_(5)).Treatments were distributed in a randomized block design using 2×2×3 factorial scheme,with four replicates.Plants were grown in 8-L pots for 70 days under greenhouse conditions.Morphological characteristics,leaf P concentration,and P use efficiency of corn plants were evaluated.Our results showed that the multiple inoculations of Bacillus subtilis,B.megaterium,B.velezencis,and Pseudomonas fluorescens are a promising sustainable agricultural practice to be recommended for corn cultivation,especially because it improves the development and P use efficiency of plants fertilized with medium P levels,which reduces the costs associated with mineral phosphate fertilization,a non-renewable fertilizer source.In sandy tropical soilwith low P availability,applying intermediate rates of highly soluble phosphate fertilizer,such as triple superphosphate,is sufficient to maximize plant development and the nutritional status of corn crops for sustainable production with low environmental impact.展开更多
The use of carbon from waste biomass has the potential to eliminate the drawbacks of Li-S batteries and improve their overall performance.Chrome-tanned-leather-shavings(CTLS)are a readily available waste product that ...The use of carbon from waste biomass has the potential to eliminate the drawbacks of Li-S batteries and improve their overall performance.Chrome-tanned-leather-shavings(CTLS)are a readily available waste product that can be transformed into porous carbon.We prepared an ac-tivated carbon by microwave pyrolysis combined with KOH activator using the CTLS as starting materials.The carbon had a specific surface area of 556 m^(2)g^(-1) and a honeycomb-like structure.Two kinds of N-doped activated carbons were then synthesized by thermal decomposition of the activated carbon,either combined with urea,or impregnated with eth-anolamine.Both N-doped activated carbons have an in-creased number of nitrogen and amine surface groups.However,only the urea treatment was effective in improv-ing the initial capacity of the cell(1363 mAh g^(-1)),which is probably linked to the sorption of long-chain polysulfides.This investigation confirms that it is possible to use the thermal de-composition of urea to obtain carbon materials from CTLS for use as the sulfur-host cathode in Li-S batteries and improve their performance.A radial basis function neural network was fitted to provide statistical support for the experimental results,which confirmed the importance of the nitrogen content of the carbons in determining the discharge capacity of the cells.展开更多
The Andean montane forests provide a wide range of ecosystem services like water supply, carbon sequestration, and biodiversity preservation. Restoration of these forests is critical due to their degraded state and th...The Andean montane forests provide a wide range of ecosystem services like water supply, carbon sequestration, and biodiversity preservation. Restoration of these forests is critical due to their degraded state and the need to recover, maintain and enhance the ecosystem services they provide. However, we lack understanding of aboveground biomass (AGB) accumulation in restored Andean montane forests. AGB is a key indicator of ecosystem productivity and provides essential data on vegetation carbon stocks, permitting the assess successfulness of restoration efforts. In 2010 the initiative Más Bosques para Medellín was formulated in Medellín City, tropical Andes, Colombia, aiming to restore the forests located in the surrounding rural areas of the city, with interest in preserving the ecosystems services like water supply. The project established 548 ha of mixed plantations with native species. After 13 years, our study aims to developed in situ allometric equations and to evaluate AGB accumulation to assess restoration performance. We measured, harvested, and weighted 144 individuals from these arrangements to fit a general equation for the project and six specific equations for each one of the six most frequent species. The AGB had a positive correlation with diameter at breast height (D), total height (H) and specific wood density (WD). The best general equation uses D and WD as predictors (R^(2) = 0.928). The specific species equations certainly responded to the functional traits of each species. Using the latest inventory of permanent plots of the project we estimated a mean AGB accumulation of 41.91 ± 30.34 Mg ha^(–1) and a total accumulation of 22,996.05 Mg of AGB for the 548 ha. We compared these results with studies developed for natural forest in the region and other land covers. We found contrast behaviors in the AGB accumulation across our study zones. The developed equations have broad applicability across the Andes region, offering valuable insights for similar restoration initiatives. Furthermore, will facilitate the assessment of current restoration efforts and inform scientifically based decisions for future mixed plantation practices.展开更多
Concerns about air quality in dental clinics where aerosol generation during procedures poses significant health risks,have prompted investigations on advanced disinfection technologies.This editorial describes the st...Concerns about air quality in dental clinics where aerosol generation during procedures poses significant health risks,have prompted investigations on advanced disinfection technologies.This editorial describes the strengths and limitations of ventilation and aerosol control measures in dental offices,especially with respect to the use of graphene nanocomposites.The potential of graphene nanocomposites as an innovative solution to aerosol-associated health risks is examined in this review due to the unique properties of graphene(e.g.,high con-ductivity,mechanical strength,and antimicrobial activity).These properties have produced promising results in various fields,but the application of graphene in dentistry remains unexplored.The recent study by Ju et al which was published in World Journal of Clinical Cases evaluated the effectiveness of graphene-based air disinfection systems in dental clinics.The study demonstrated that graphene-based disinfection techniques produced significant reductions in suspended particulate matter and bacterial colony counts,when co-mpared with traditional methods.Despite these positive results,challenges such as material saturation,frequency of filter replacement,and associated costs must be addressed before widespread adoption of graphene-based disinfection techniques in clinical practice.Therefore,there is need for further research on material structure optimization,long-term safety evaluations,and broader clinical applications,in order to maximize their positive impact on public health.展开更多
The Kunene Complex(KC)represents a very large Mesoproterozoic igneous body,mainly composed of anorthosites and gabbroic rocks that extends from SW Angola to NW Namibia(outcropping 18,000 km^(2),NE-SW trend,and ca.350 ...The Kunene Complex(KC)represents a very large Mesoproterozoic igneous body,mainly composed of anorthosites and gabbroic rocks that extends from SW Angola to NW Namibia(outcropping 18,000 km^(2),NE-SW trend,and ca.350 km long and up to 50 km wide).Little is known about its structure at depth.Here,we use recently acquired aerogeophysical data to accurately determine its hidden extent and to unravel its morphology at depth.These data have been interpreted and modelled to investigate the unexposed KC boundaries,reconstructing the upper crustal structure(between 0 and 15 km depth)overlain by the thin sedimentary cover of the Kalahari Basin.The modelling reveals that the KC was emplaced in the upper crust and extends in depth up to ca.5 km,showing a lobular geometry and following a large NE-SW to NNE-SSW linear trend,presumably inherited from older Paleoproterozoic structures.The lateral continuation of the KC to the east(between 50 and 125 km)beneath the Kalahari Cenozoic sediments suggests an overall size three times the outcropping dimension(about 53,500 km^(2)).This affirmation clearly reinforces the economic potential of this massif,related to the prospecting of raw materials and certain types of economic mineralization(Fe-Ti oxides,metallic sulphides or platinum group minerals).Up to 11 lobes have been isolated with dimensions ranging from 135.5 to 37.3 km in length and 81.9 to 20.7 km in width according to remanent bodies revealed by TMI mapping.A total volume of 65,184 km3 was calculated only for the magnetically remanent bodies of the KC.A long-lasting complex contractional regime,where large strike-slip fault systems were involved,occurred in three kinematic pulses potentially related to a change of velocity or convergence angle acting on previous Paleoproterozoic inherited sutures.The coalescent magmatic pulses can be recognized by means of magnetic anomalies,age of the bodies as well as the lineations inferred in this work:(i)Emplacement of the eastern mafic bodies and granites in a stage of significant lateral extension in a transtensional context between 1500 Ma and 1420 Ma;(ii)Migration of the mantle derived magmas westwards with deformation in a complex contractional setting with shearing structures involving western KC bodies and basement from 1415 Ma to 1340 Ma;(iii)NNW-SSE extensional structures are relocated westwards,involving mantle magmas,negative flower structures and depression that led to the formation of late Mesoproterozoic basins from 1325 Ma to 1170 Ma.Additionally,we detect several first and second order structures to place the structuring of the KC in a craton-scale context in relation to the crustal structures detected in NW Namibia.展开更多
The impregnation of nanoparticles magnetified into wood had been developed by different methods,like surface chemical coprecipitation and vacuum-pressure coprecipitation of magnetic nanoparticles(NPs).However,there is...The impregnation of nanoparticles magnetified into wood had been developed by different methods,like surface chemical coprecipitation and vacuum-pressure coprecipitation of magnetic nanoparticles(NPs).However,there is a lack of information on the best method to coprecipitation NPs.Then,the present study has the objective to measure the effects of the impregnation process of wood veneers through two in situ processes(immersion and vacuum-pressure)using a solution of FeCl_(3)·6H_(2)O,FeCl_(2)·4H_(2)O and ammonia in three tropical species(Pinus oocarpa,Vochysia ferruginea and Vochysia guatemalensis).It was measured the degree of synthesis of iron NPs using weight and density gains,Fe^(3+) absorption,emission scanning electron microscope(SEM),Fournier transform infrared spectroscopy(FT-IR)and for magnetic properties were measured using vibrating sample magnetometry(VSM).After 5-layer veneer panels were fabricated,we evaluated their physical and mechanical properties.Wood samples impregnated by vacuum-pressure methods showed the higher amount of Fe_(3)O_(4)NPs formation,which was observed in the SEM,X-ray diffraction(XDR),FT-IR and VSM.Vacuum-pressure on treatment presented higher ferrite signals and better magnetic properties.Vochysia ferruginea presented the greatest magnetization properties.The magnetization treated causes probably a degradation of the cell wall,which weakens its mechanical properties,especially internal bonding.展开更多
Tezontle from the Anáhuac Basin became Mexico’s second IUGS Heritage Stone in August 2024.This volcanic scoria of basaltic to basaltic-andesitic composition,once considered a‘providential gift’or a‘divine mat...Tezontle from the Anáhuac Basin became Mexico’s second IUGS Heritage Stone in August 2024.This volcanic scoria of basaltic to basaltic-andesitic composition,once considered a‘providential gift’or a‘divine material’,has been used for over twenty centuries in countless architectural monuments,many of which are included in UNESCO’s World Heritage List.The abundant availability of tezontle in central Mexico,combined with its exceptional physical properties of lightness,hardness,and durability,made it the preferred material for building the massive structures of the monumental Pre-Hispanic City of Teotihuacan(1st-7th centuries).展开更多
The effect of the inclusion of chestnut in pigs ifnishing diet on volatile compounds of dry-cured Celta ham was studied. Twelve hams of each type （from three different pigs ifnishing diets：concentrate （CO）, mixed ...The effect of the inclusion of chestnut in pigs ifnishing diet on volatile compounds of dry-cured Celta ham was studied. Twelve hams of each type （from three different pigs ifnishing diets：concentrate （CO）, mixed （MI） and chestnut （CH）） were used. Volatiles were extracted using a purge-and-trap method and analyzed by gas chromatography/mass spectrometry （GC/MS）. Thirty-nine volatile compounds were identified in dry-cured Celta ham samples. Most abundant volatiles in ham samples were aldehydes, which represented respectively, 53% （CO）, 51% （MI） and 46% （CH） of the total volatile composition. With the exception of 2-butenal, 2-methyl, all aldehydes were affected by feeding system. On the other hand, hydrocarbons n-alkanes were the second major group in the volatile proifle of dry-cured Celta hams and represented 28.9, 35.7 and 32.4%of the total volatile composition for CO, MI and CH groups, respectively. Ham samples from chestnut group showed a higher content of alcohols and this result could be related with the inclusion of chestnut in the ifnishing diet of pigs. Principal component analysis showed a good separation among groups. The discriminant analysis selected eight variables （butanoic acid, hexanal, octanal, nonenal （E）, decenal （E）, tetradecane, decane trimethyl and pyridine 2-methyl） and calculated two discriminating functions to predict if chestnut has been included in the ifnishing diet. Thus, it was possible to discriminate between groups fed with ifnishing diets containing chestnuts in their composition （mixed and chestnut group）.展开更多
The combination of complete cytoreductive surgery and perioperative intraperitoneal chemotherapy provides the only chance for long-term survival for selected patients diagnosed with a variety of peritoneal neoplasms,e...The combination of complete cytoreductive surgery and perioperative intraperitoneal chemotherapy provides the only chance for long-term survival for selected patients diagnosed with a variety of peritoneal neoplasms,either primary or secondary to digestive or gynecologic malignancy.Hyperthermic intraperitoneal chemotherapy (HIPEC) delivered in the operating room once the cytoreductive surgical procedure is fi nalized,constitutes the most common form of administration of perioperative intraperitoneal chemotherapy.This may be complemented in some instances with early postoperative intraperitoneal chemotherapy (EPIC).HIPEC combines the pharmacokinetic advantage inherent to the intracavitary delivery of certain cytotoxic drugs,which results in regional dose intensification,with the direct cytotoxic effect of hyperthermia.Hyperthermia exhibits a selective cell-killing effect in malignant cells by itself,potentiates the cytotoxic effect of certain chemotherapy agents and enhances the tissue penetration of the administered drug.The chemotherapeutic agents employed in HIPEC need to have a cell cycle nonspecific mechanism of action and should ideally show a heat-synergistic cytotoxic effect.Delivery of HIPEC requires an apparatus that heats and circulates the chemotherapeutic solution so that a stable temperature is maintained in the peritoneal cavity during the procedure.An open abdomen (Coliseum) or closed abdomen technique may be used,with no signif icant differences in eff icacy proven to date.Specif ic technical training and a solid knowledge of regional chemotherapy management are required.Concerns about safety of the procedure for operating room personnel are expected but are manageable if universal precautions and standard chemotherapy handling procedures are used.Different HIPEC drug regimens and dosages are currently in use.A tendency for concurrent intravenous chemotherapy administration (bidirectional chemotherapy,so-called "HIPEC plus") has been observed in recent years,with the aim to further enhance the cytotoxic potential of HIPEC.Future trials to ascertain the ideal HIPEC regimen in different diseases and to evaluate the efficacy of new drugs or drug combinations in this context are warranted.展开更多
Alopecia areata is a disease of the hair follicles, with strong evidence supporting autoimmune etiology. Alopecia areata is frequently associated with immune-medi- ated diseases with skin manifestations such as psoria...Alopecia areata is a disease of the hair follicles, with strong evidence supporting autoimmune etiology. Alopecia areata is frequently associated with immune-medi- ated diseases with skin manifestations such as psoriasis and lichen planus, or without skin manifestations such as autoimmune thyroiditis and idiopathic thrombocytopenic purpura. Helicobacter py/ori （H. pylorl） infection is present in around 50% of the world＇s population and has been associated with a variety of immune-mediated extra-digestive disorders including autoimmune thyroid- itis, idiopathic thrombocytopenic purpura, and psoriasis. A case of a 43-year old man with an 8-too history of alopecia areata of the scalp and beard is presented. The patient was being treated by a dermatologist and had psychiatric support, without any improvement. He had a history of dyspepsia and the urea breath test confirmed H. pylori infection. The patient went into remission from alopecia areata after H. pylori eradication. If such an association is confirmed by epidemiological studies designed for this purpose, new therapeutic options could be available for these patients, especially in areas where infection with H, pylori is highly prevalent.展开更多
Aluminum alloy samples, 6061-T6 and 2219-T42, were exposed to Caribbean seawater for 90 d. The fluctuations of open circuit potential, considered as electrochemical noise (EN), were used to characterize and compare in...Aluminum alloy samples, 6061-T6 and 2219-T42, were exposed to Caribbean seawater for 90 d. The fluctuations of open circuit potential, considered as electrochemical noise (EN), were used to characterize and compare initial pitting events, which appeared on their surfaces. EN analysis was carried out using the power spectral density (PSD) vs frequency. The decrease of the β exponent in PSD graphs indicated a release of spontaneous energy with the progress of pit formation in seawater. The fluctuations were associated with the breakdown and formation of new corrosion layers. The values of β exponent in PSD graphs suggest that corrosion process of AA2219-T42 alloy occurs as a persistent non-stationary process, the dynamics of which is controlled by fractional Brownian motion (fBm), while on AA6061-T6 alloy the corrosion process was dominated by stationary and weakly persistent features, with the contribution of fractional Gaussian noise (fGn). After the exposure in seawater, SEM-EDX analysis revealed insoluble intermetallic particles on the alloys, rich in Cu or Fe and irregularly distributed. The preferential dissolution of Mg and Al occurs from the S-phase (Al2CuMg) of AA2219-T42 alloy.展开更多
Helicobacter pylori (H. pylori) is the most common infection in humans, with a marked disparity between developed and developing countries. Although H. pylori infections are asymptomatic in most infected individuals, ...Helicobacter pylori (H. pylori) is the most common infection in humans, with a marked disparity between developed and developing countries. Although H. pylori infections are asymptomatic in most infected individuals, they are intimately related to malignant gastric conditions such as gastric cancer and gastric mucosa-associated lymphoid tissue (MALT) lymphoma and to benign diseases such as gastritis and duodenal and gastric peptic ulcers. Since it was learned that bacteria could colonize the gastric mucosa, there have been reports in the medical literature of over 50 extragastric manifestations involving a variety medical areas of specialization. These areas include cardiology, dermatology, endocrinology, gynecology and obstetrics, hematology, pneumology, odontology, ophthalmology, otorhinolaryngology and pediatrics, and they encompass conditions with a range of clear evidence between the H. pylori infection and development of the disease. This literature review covers extragastric manifestations of H. pylori infection in the hematology field. It focuses on conditions that are included in international consensus and management guides for H. pylori infection, specifically iron deficiency, vitamin B<sub>12</sub> (cobalamin) deficiency, immune thrombocytopenia, and MALT lymphoma. In addition, there is discussion of other conditions that are not included in international consensus and management guides on H. pylori, including auto-immune neutropenia, antiphospholipid syndrome, plasma cell dyscrasias, and other hematologic diseases.展开更多
Objective:To evaluate in ritro antimicrobial activities of selected 58 ethno-medicinal plant extracts with a view to assess their therapeutic potential.Methods:A total of 58 traditional Chinese medicinal plants were c...Objective:To evaluate in ritro antimicrobial activities of selected 58 ethno-medicinal plant extracts with a view to assess their therapeutic potential.Methods:A total of 58 traditional Chinese medicinal plants were carefully selected based on the literature review and their traditional use.The antimicrobial activities of ethanol extracts of these medicinal plants were tested against fungi(Aspergillus funigaius),yeast(Candida albicans),gram-negative(Acirelobacter haumannii and Pseudornnruis aeruginosa)and gram-positive bacteria(Staphglococcus aureus).The activities were tested at three different concentrations of 1.00,0.10 and 0.01 mg/mL.The data was analysed using Gene data Screener program.Results:The measured antimicrobial activities indicated that out of the 58 plant extracts,15 extracts showed anti-fungal activity and 23 extracts exhibited anti-bacterial activity.Eight plant extracts have exhibited both anti-bacterial and anti-fungal activities.For instance,Eucommia ulmoides,Pohgonum cuspidcrtum,Poria cocas and Uncaria rhineophylla showed activity against both bacterial and fungal strains,indicating their broad spectrum of activity.Conclusions:The results revealed that the ethanol extracts of 30 plants out of the selected 58 possess significant antimicrobial activities.It is interesting to note that the findings from the current study are consistent with the traditional use.A clear correlation has also been found between the antimicrobial activity and the flavonoid content of the plant extracts which is in agreement with the literature.Hence.the results presented here can be used to guide the selection of potential plant species for the isolation and structure elucidation of novel antimicrobial compounds in order to establish the structure-activity relationship.This in turn is expected to lead the way to the discovery of novel antimicrobial agents for therapeutic use.展开更多
Green tea has been an important beverage for humans since ancient times, widely consumed and considered to have health benefits by traditional medicine in Asian countries. Green tea phenolic compounds are predominatel...Green tea has been an important beverage for humans since ancient times, widely consumed and considered to have health benefits by traditional medicine in Asian countries. Green tea phenolic compounds are predominately composed of catechin derivatives, although other compounds such as flavonols and phenolic acids are also present in lower proportion. The bioactivity exerted by these compounds has been associated with reduced risk of severe illnesses such as cancer, cardiovascular and neurodegenerative diseases. Particularly, epigallocatechin gallate has been implicated in alteration mechanisms with protective effect in these diseases as indicated by several studies about the effect of green tea consumption and mechanistic explanation through in vitro and in vivo experiments. The biological activity of green tea phenolic compounds also promotes a protective effect by antioxidant mechanisms in biological and food systems, preventing the oxidative damage by acting over either precursors or reactive species. Extraction of phenolic compounds influences the antioxidant activity and promotes adequate separation from green tea leaves to enhance the yield and/or antioxidant activity. Application of green tea phenolic compounds is of great interest because the antioxidant status of the products is enhanced and provides the product with additional antioxidant activity or reduces the undesirable changes of oxidative reactions while processing or storing food.In this scenario, meat and meat products are greatly influenced by oxidative deterioration and microbial spoilage, leading to reduced shelf life. Green tea extracts rich in phenolic compounds have been applied to increase shelf life with comparable effect to synthetic compounds, commonly used by food industry. Green tea has great importance in general health in technological application, however more studies are necessary to elucidate the impact in pathways related to other diseases and food applications.展开更多
文摘The biochemical response of Coffea arabica var.Borbon to chitosan and chitosan oligosaccharides(COS)was evaluated in one-year-old plants under greenhouse conditions.COS solutions were synthesized through chemical and physical hydrolysis using acetic acid,hydrogen peroxide,and microwave irradiation.The obtained COS had an average molecular weight(Mw)of 3549.90±0.33 Daltons(Da),a deacetylation degree(DD)of 76.64±1.12%,and a polymerization degree(PD)of 18.91±0.0018.Solutions of chitosan and COS were applied to C.arabica var.Borbon at concentrations of 0.25,0.5,and 1 wt%.The experimental design was conducted using a completely randomized design with four replications.The biochemical responses assessed included soluble protein content,phenylalanine ammonia-lyase(PAL),chitinase,β-1,3-glucanase,peroxidase,catalase,and chlorophyll fluorescence.The application of COS demonstrated significant differences(α=0.05)in protein concentration,with the activity ofβ-1,3-glucanase,chitinase,and catalase being 1.5,7.5,and 3.9 times higher,respectively,while showing similar behavior to chitosan in PAL activity,both up to 4.4 times higher than the distilled water control and lower than chitosan in peroxidase activity.Treatments with chitosan yielded a higher photochemical efficiency of Photosystem II(PSII).The application of COS suggests a viable foliar alternative to active plant defense mechanisms without the risk of phytotoxicity.
文摘Exogenous proline is an effective agent for increasing plant tolerance to abiotic stress in plants. In this study, we evaluated its effect on seedlings of Siete Caldos chili pepper (Capsicum frutescens), a semi-domesticated variety. The Capsicum genus is known for its sensitivity to water stress. We pretreated the seedlings’ roots by immersing them in proline solutions (0, 2.5, 5, 7.5, and 10 mM) for 48 h. Then, we exposed them to water stress using a Hoagland nutrient solution supplemented with 10% polyethylene glycol (PEG-8000) for nine days. We analyzed key physiological and biochemical parameters, including relative water content, cell membrane stability index, electrolyte leakage, chlorophyll, and proline content. The results indicated that proline concentrations of 2.5 and 5 mM significantly increased tolerance to water stress, with 100% survival. These seedlings maintained greater hydration and cell membrane stability compared to non-pretreated seedlings. In contrast, at the highest concentrations (7.5 and 10 mM Pro), survival was 63.63% and 54.54%, respectively. This study demonstrated that exogenous proline enhances water stress tolerance in Capsicum frutescens seedlings by mitigating the negative impact on physiological and biochemical processes vital for survival. This theoretical foundation can be applied to improve chili seedling performance in controlled production environments.
文摘A significant portion of losses in the fruit and vegetable sector are caused by the necrotrophic fungus Botrytis cinerea,due to its high prevalence in over 1000 crop species.Identifying a technology capable of exclusively inhibiting its growth and development remains challenging;therefore,various treatments have been proposed to act synergistically in preventing the spread of this pathogen.The objective of this study was to evaluate an ultrasound-assisted treatment combined with chitosan to control the development of B.cinerea.In vitro analyses showed that combining temperature,ultrasound,and chitosan inhibited the fungal radial growth by 80%,reduced sporulation,and decreased germination.Electrolyte leak analysis indicated damage to the B.cinerea cell wall,causing intracellular material to escape into the environment.Scanning and transmission electron microscopy images also revealed severe structural damage,including loss of the cytoplasmic membrane and cell lysis.
文摘A geostatistical study was conducted with the objective of developing a better understanding of the sediments deposited in the tailings dam of an iron mine located in Brazil.The samples,derived from two drilling campaigns conducted in 2001 and 2010,were statistically evaluated and validated for the construction of both a 3D geological model and an estimated model.The geological body modeling process was performed using an implicit method,which was based on the interpretation and adjustments of vertical sections and considered the positions of the samples and the grades of the chemical components of interest.In addition,the primitive topography was also considered to determine the base and limits of the deposit,as well as the current topography.The ordinary kriging(OK)method was chosen to estimate the grades of the chemical components and the retained/passing percentages of the particle size fractions described in the samples.The kriging model was validated through two analyses:mean comparison and drift analyses.The total tonnage of the estimated model was 287.14 Mt,with an average Fe grade of 63.89%.
基金financed in part by the Coordenacao de Aperfeicoamento de Pessoal de Nível Superior-Brasil(CAPES)-Finance Code 001financial resources from the Fundacao de Apoio ao Desenvolvimento do Ensino,Ciencia e Tecnologia do Estado de Mato Grosso do Sul—FUNDECT(Termo de Outorga:133/2023/SIAFEM:33108).
文摘Corn(Zea mays L.)is a very sensitive crop to phosphorus(P)deficiency during the early development phase,which may be a limiting factor for the sustainable production of this crop in P-deficient tropical soils.However,scientific evidence indicates that inoculation with phosphate-solubilizing bacteria can improve the development,uptake,and P-use efficiency of corn plants.In the present study,two contrasting corn hybrids were investigated for their responsiveness to multiple inoculations of Bacillus subtilis,B.megaterium,B.velezencis,and Pseudomonas fluorescens and application of phosphate fertilizer rates in the sandy soil of the Brazilian Cerrado.Plants from stable(DKB 360 PRO3)and responsive(DKB 255 PRO3)corn hybrids were inoculated with 0 and 2 mL of inoculant containing multiple phosphate-solubilizing bacteria and fertilized with low(0 mg P·kg^(-1)),medium(40 mg P·kg^(-1))and high(80 mg P·kg^(-1))levels of phosphate fertilizer using triple superphosphate(46% of P_(2)O_(5)).Treatments were distributed in a randomized block design using 2×2×3 factorial scheme,with four replicates.Plants were grown in 8-L pots for 70 days under greenhouse conditions.Morphological characteristics,leaf P concentration,and P use efficiency of corn plants were evaluated.Our results showed that the multiple inoculations of Bacillus subtilis,B.megaterium,B.velezencis,and Pseudomonas fluorescens are a promising sustainable agricultural practice to be recommended for corn cultivation,especially because it improves the development and P use efficiency of plants fertilized with medium P levels,which reduces the costs associated with mineral phosphate fertilization,a non-renewable fertilizer source.In sandy tropical soilwith low P availability,applying intermediate rates of highly soluble phosphate fertilizer,such as triple superphosphate,is sufficient to maximize plant development and the nutritional status of corn crops for sustainable production with low environmental impact.
文摘The use of carbon from waste biomass has the potential to eliminate the drawbacks of Li-S batteries and improve their overall performance.Chrome-tanned-leather-shavings(CTLS)are a readily available waste product that can be transformed into porous carbon.We prepared an ac-tivated carbon by microwave pyrolysis combined with KOH activator using the CTLS as starting materials.The carbon had a specific surface area of 556 m^(2)g^(-1) and a honeycomb-like structure.Two kinds of N-doped activated carbons were then synthesized by thermal decomposition of the activated carbon,either combined with urea,or impregnated with eth-anolamine.Both N-doped activated carbons have an in-creased number of nitrogen and amine surface groups.However,only the urea treatment was effective in improv-ing the initial capacity of the cell(1363 mAh g^(-1)),which is probably linked to the sorption of long-chain polysulfides.This investigation confirms that it is possible to use the thermal de-composition of urea to obtain carbon materials from CTLS for use as the sulfur-host cathode in Li-S batteries and improve their performance.A radial basis function neural network was fitted to provide statistical support for the experimental results,which confirmed the importance of the nitrogen content of the carbons in determining the discharge capacity of the cells.
基金supported by resources of the Secretary of Environment of the Medellín district,through the agreement N°001-2023 between this entity,the Faculty of Agricultural Sciences of National University of Colombia at Medellín
文摘The Andean montane forests provide a wide range of ecosystem services like water supply, carbon sequestration, and biodiversity preservation. Restoration of these forests is critical due to their degraded state and the need to recover, maintain and enhance the ecosystem services they provide. However, we lack understanding of aboveground biomass (AGB) accumulation in restored Andean montane forests. AGB is a key indicator of ecosystem productivity and provides essential data on vegetation carbon stocks, permitting the assess successfulness of restoration efforts. In 2010 the initiative Más Bosques para Medellín was formulated in Medellín City, tropical Andes, Colombia, aiming to restore the forests located in the surrounding rural areas of the city, with interest in preserving the ecosystems services like water supply. The project established 548 ha of mixed plantations with native species. After 13 years, our study aims to developed in situ allometric equations and to evaluate AGB accumulation to assess restoration performance. We measured, harvested, and weighted 144 individuals from these arrangements to fit a general equation for the project and six specific equations for each one of the six most frequent species. The AGB had a positive correlation with diameter at breast height (D), total height (H) and specific wood density (WD). The best general equation uses D and WD as predictors (R^(2) = 0.928). The specific species equations certainly responded to the functional traits of each species. Using the latest inventory of permanent plots of the project we estimated a mean AGB accumulation of 41.91 ± 30.34 Mg ha^(–1) and a total accumulation of 22,996.05 Mg of AGB for the 548 ha. We compared these results with studies developed for natural forest in the region and other land covers. We found contrast behaviors in the AGB accumulation across our study zones. The developed equations have broad applicability across the Andes region, offering valuable insights for similar restoration initiatives. Furthermore, will facilitate the assessment of current restoration efforts and inform scientifically based decisions for future mixed plantation practices.
文摘Concerns about air quality in dental clinics where aerosol generation during procedures poses significant health risks,have prompted investigations on advanced disinfection technologies.This editorial describes the strengths and limitations of ventilation and aerosol control measures in dental offices,especially with respect to the use of graphene nanocomposites.The potential of graphene nanocomposites as an innovative solution to aerosol-associated health risks is examined in this review due to the unique properties of graphene(e.g.,high con-ductivity,mechanical strength,and antimicrobial activity).These properties have produced promising results in various fields,but the application of graphene in dentistry remains unexplored.The recent study by Ju et al which was published in World Journal of Clinical Cases evaluated the effectiveness of graphene-based air disinfection systems in dental clinics.The study demonstrated that graphene-based disinfection techniques produced significant reductions in suspended particulate matter and bacterial colony counts,when co-mpared with traditional methods.Despite these positive results,challenges such as material saturation,frequency of filter replacement,and associated costs must be addressed before widespread adoption of graphene-based disinfection techniques in clinical practice.Therefore,there is need for further research on material structure optimization,long-term safety evaluations,and broader clinical applications,in order to maximize their positive impact on public health.
基金supported by the subsidiary programme“Ayudas Extraordinarias Menciones Excelencia Severo Ochoa”of the CN IGME-CSIC(project AECEX2021,grant 15903)the University of Minnesota and National Science Foundation(award NSF-EAR 2153786)+1 种基金the Portuguese Foundation for Science and Technology(FCT)support,Geosciences Center project UIDB/00073/2020(doi:10.54499/UIDB/00073/2020)University of Coimbra and and GeoBioTec project UIDB/04035/2020(doi:10.54499/UIDB/04035/2020),Nova School of Science and Technology.
文摘The Kunene Complex(KC)represents a very large Mesoproterozoic igneous body,mainly composed of anorthosites and gabbroic rocks that extends from SW Angola to NW Namibia(outcropping 18,000 km^(2),NE-SW trend,and ca.350 km long and up to 50 km wide).Little is known about its structure at depth.Here,we use recently acquired aerogeophysical data to accurately determine its hidden extent and to unravel its morphology at depth.These data have been interpreted and modelled to investigate the unexposed KC boundaries,reconstructing the upper crustal structure(between 0 and 15 km depth)overlain by the thin sedimentary cover of the Kalahari Basin.The modelling reveals that the KC was emplaced in the upper crust and extends in depth up to ca.5 km,showing a lobular geometry and following a large NE-SW to NNE-SSW linear trend,presumably inherited from older Paleoproterozoic structures.The lateral continuation of the KC to the east(between 50 and 125 km)beneath the Kalahari Cenozoic sediments suggests an overall size three times the outcropping dimension(about 53,500 km^(2)).This affirmation clearly reinforces the economic potential of this massif,related to the prospecting of raw materials and certain types of economic mineralization(Fe-Ti oxides,metallic sulphides or platinum group minerals).Up to 11 lobes have been isolated with dimensions ranging from 135.5 to 37.3 km in length and 81.9 to 20.7 km in width according to remanent bodies revealed by TMI mapping.A total volume of 65,184 km3 was calculated only for the magnetically remanent bodies of the KC.A long-lasting complex contractional regime,where large strike-slip fault systems were involved,occurred in three kinematic pulses potentially related to a change of velocity or convergence angle acting on previous Paleoproterozoic inherited sutures.The coalescent magmatic pulses can be recognized by means of magnetic anomalies,age of the bodies as well as the lineations inferred in this work:(i)Emplacement of the eastern mafic bodies and granites in a stage of significant lateral extension in a transtensional context between 1500 Ma and 1420 Ma;(ii)Migration of the mantle derived magmas westwards with deformation in a complex contractional setting with shearing structures involving western KC bodies and basement from 1415 Ma to 1340 Ma;(iii)NNW-SSE extensional structures are relocated westwards,involving mantle magmas,negative flower structures and depression that led to the formation of late Mesoproterozoic basins from 1325 Ma to 1170 Ma.Additionally,we detect several first and second order structures to place the structuring of the KC in a craton-scale context in relation to the crustal structures detected in NW Namibia.
文摘The impregnation of nanoparticles magnetified into wood had been developed by different methods,like surface chemical coprecipitation and vacuum-pressure coprecipitation of magnetic nanoparticles(NPs).However,there is a lack of information on the best method to coprecipitation NPs.Then,the present study has the objective to measure the effects of the impregnation process of wood veneers through two in situ processes(immersion and vacuum-pressure)using a solution of FeCl_(3)·6H_(2)O,FeCl_(2)·4H_(2)O and ammonia in three tropical species(Pinus oocarpa,Vochysia ferruginea and Vochysia guatemalensis).It was measured the degree of synthesis of iron NPs using weight and density gains,Fe^(3+) absorption,emission scanning electron microscope(SEM),Fournier transform infrared spectroscopy(FT-IR)and for magnetic properties were measured using vibrating sample magnetometry(VSM).After 5-layer veneer panels were fabricated,we evaluated their physical and mechanical properties.Wood samples impregnated by vacuum-pressure methods showed the higher amount of Fe_(3)O_(4)NPs formation,which was observed in the SEM,X-ray diffraction(XDR),FT-IR and VSM.Vacuum-pressure on treatment presented higher ferrite signals and better magnetic properties.Vochysia ferruginea presented the greatest magnetization properties.The magnetization treated causes probably a degradation of the cell wall,which weakens its mechanical properties,especially internal bonding.
文摘Tezontle from the Anáhuac Basin became Mexico’s second IUGS Heritage Stone in August 2024.This volcanic scoria of basaltic to basaltic-andesitic composition,once considered a‘providential gift’or a‘divine material’,has been used for over twenty centuries in countless architectural monuments,many of which are included in UNESCO’s World Heritage List.The abundant availability of tezontle in central Mexico,combined with its exceptional physical properties of lightness,hardness,and durability,made it the preferred material for building the massive structures of the monumental Pre-Hispanic City of Teotihuacan(1st-7th centuries).
基金financially supported by the Spanish Ministry of Science and Innovation(AGL2008-05274-C02-01/ALI)
文摘The effect of the inclusion of chestnut in pigs ifnishing diet on volatile compounds of dry-cured Celta ham was studied. Twelve hams of each type （from three different pigs ifnishing diets：concentrate （CO）, mixed （MI） and chestnut （CH）） were used. Volatiles were extracted using a purge-and-trap method and analyzed by gas chromatography/mass spectrometry （GC/MS）. Thirty-nine volatile compounds were identified in dry-cured Celta ham samples. Most abundant volatiles in ham samples were aldehydes, which represented respectively, 53% （CO）, 51% （MI） and 46% （CH） of the total volatile composition. With the exception of 2-butenal, 2-methyl, all aldehydes were affected by feeding system. On the other hand, hydrocarbons n-alkanes were the second major group in the volatile proifle of dry-cured Celta hams and represented 28.9, 35.7 and 32.4%of the total volatile composition for CO, MI and CH groups, respectively. Ham samples from chestnut group showed a higher content of alcohols and this result could be related with the inclusion of chestnut in the ifnishing diet of pigs. Principal component analysis showed a good separation among groups. The discriminant analysis selected eight variables （butanoic acid, hexanal, octanal, nonenal （E）, decenal （E）, tetradecane, decane trimethyl and pyridine 2-methyl） and calculated two discriminating functions to predict if chestnut has been included in the ifnishing diet. Thus, it was possible to discriminate between groups fed with ifnishing diets containing chestnuts in their composition （mixed and chestnut group）.
文摘The combination of complete cytoreductive surgery and perioperative intraperitoneal chemotherapy provides the only chance for long-term survival for selected patients diagnosed with a variety of peritoneal neoplasms,either primary or secondary to digestive or gynecologic malignancy.Hyperthermic intraperitoneal chemotherapy (HIPEC) delivered in the operating room once the cytoreductive surgical procedure is fi nalized,constitutes the most common form of administration of perioperative intraperitoneal chemotherapy.This may be complemented in some instances with early postoperative intraperitoneal chemotherapy (EPIC).HIPEC combines the pharmacokinetic advantage inherent to the intracavitary delivery of certain cytotoxic drugs,which results in regional dose intensification,with the direct cytotoxic effect of hyperthermia.Hyperthermia exhibits a selective cell-killing effect in malignant cells by itself,potentiates the cytotoxic effect of certain chemotherapy agents and enhances the tissue penetration of the administered drug.The chemotherapeutic agents employed in HIPEC need to have a cell cycle nonspecific mechanism of action and should ideally show a heat-synergistic cytotoxic effect.Delivery of HIPEC requires an apparatus that heats and circulates the chemotherapeutic solution so that a stable temperature is maintained in the peritoneal cavity during the procedure.An open abdomen (Coliseum) or closed abdomen technique may be used,with no signif icant differences in eff icacy proven to date.Specif ic technical training and a solid knowledge of regional chemotherapy management are required.Concerns about safety of the procedure for operating room personnel are expected but are manageable if universal precautions and standard chemotherapy handling procedures are used.Different HIPEC drug regimens and dosages are currently in use.A tendency for concurrent intravenous chemotherapy administration (bidirectional chemotherapy,so-called "HIPEC plus") has been observed in recent years,with the aim to further enhance the cytotoxic potential of HIPEC.Future trials to ascertain the ideal HIPEC regimen in different diseases and to evaluate the efficacy of new drugs or drug combinations in this context are warranted.
文摘Alopecia areata is a disease of the hair follicles, with strong evidence supporting autoimmune etiology. Alopecia areata is frequently associated with immune-medi- ated diseases with skin manifestations such as psoriasis and lichen planus, or without skin manifestations such as autoimmune thyroiditis and idiopathic thrombocytopenic purpura. Helicobacter py/ori （H. pylorl） infection is present in around 50% of the world＇s population and has been associated with a variety of immune-mediated extra-digestive disorders including autoimmune thyroid- itis, idiopathic thrombocytopenic purpura, and psoriasis. A case of a 43-year old man with an 8-too history of alopecia areata of the scalp and beard is presented. The patient was being treated by a dermatologist and had psychiatric support, without any improvement. He had a history of dyspepsia and the urea breath test confirmed H. pylori infection. The patient went into remission from alopecia areata after H. pylori eradication. If such an association is confirmed by epidemiological studies designed for this purpose, new therapeutic options could be available for these patients, especially in areas where infection with H, pylori is highly prevalent.
基金the partial financial support of this study from CONACYT (Grant 179110)
文摘Aluminum alloy samples, 6061-T6 and 2219-T42, were exposed to Caribbean seawater for 90 d. The fluctuations of open circuit potential, considered as electrochemical noise (EN), were used to characterize and compare initial pitting events, which appeared on their surfaces. EN analysis was carried out using the power spectral density (PSD) vs frequency. The decrease of the β exponent in PSD graphs indicated a release of spontaneous energy with the progress of pit formation in seawater. The fluctuations were associated with the breakdown and formation of new corrosion layers. The values of β exponent in PSD graphs suggest that corrosion process of AA2219-T42 alloy occurs as a persistent non-stationary process, the dynamics of which is controlled by fractional Brownian motion (fBm), while on AA6061-T6 alloy the corrosion process was dominated by stationary and weakly persistent features, with the contribution of fractional Gaussian noise (fGn). After the exposure in seawater, SEM-EDX analysis revealed insoluble intermetallic particles on the alloys, rich in Cu or Fe and irregularly distributed. The preferential dissolution of Mg and Al occurs from the S-phase (Al2CuMg) of AA2219-T42 alloy.
文摘Helicobacter pylori (H. pylori) is the most common infection in humans, with a marked disparity between developed and developing countries. Although H. pylori infections are asymptomatic in most infected individuals, they are intimately related to malignant gastric conditions such as gastric cancer and gastric mucosa-associated lymphoid tissue (MALT) lymphoma and to benign diseases such as gastritis and duodenal and gastric peptic ulcers. Since it was learned that bacteria could colonize the gastric mucosa, there have been reports in the medical literature of over 50 extragastric manifestations involving a variety medical areas of specialization. These areas include cardiology, dermatology, endocrinology, gynecology and obstetrics, hematology, pneumology, odontology, ophthalmology, otorhinolaryngology and pediatrics, and they encompass conditions with a range of clear evidence between the H. pylori infection and development of the disease. This literature review covers extragastric manifestations of H. pylori infection in the hematology field. It focuses on conditions that are included in international consensus and management guides for H. pylori infection, specifically iron deficiency, vitamin B<sub>12</sub> (cobalamin) deficiency, immune thrombocytopenia, and MALT lymphoma. In addition, there is discussion of other conditions that are not included in international consensus and management guides on H. pylori, including auto-immune neutropenia, antiphospholipid syndrome, plasma cell dyscrasias, and other hematologic diseases.
基金funded by the University of Western Sydney and the Fundacion MEDINAa public-private partnership of Merck Sharp&Dohme de Espana S.A./Universidad de Granada/Junta de Andalucia
文摘Objective:To evaluate in ritro antimicrobial activities of selected 58 ethno-medicinal plant extracts with a view to assess their therapeutic potential.Methods:A total of 58 traditional Chinese medicinal plants were carefully selected based on the literature review and their traditional use.The antimicrobial activities of ethanol extracts of these medicinal plants were tested against fungi(Aspergillus funigaius),yeast(Candida albicans),gram-negative(Acirelobacter haumannii and Pseudornnruis aeruginosa)and gram-positive bacteria(Staphglococcus aureus).The activities were tested at three different concentrations of 1.00,0.10 and 0.01 mg/mL.The data was analysed using Gene data Screener program.Results:The measured antimicrobial activities indicated that out of the 58 plant extracts,15 extracts showed anti-fungal activity and 23 extracts exhibited anti-bacterial activity.Eight plant extracts have exhibited both anti-bacterial and anti-fungal activities.For instance,Eucommia ulmoides,Pohgonum cuspidcrtum,Poria cocas and Uncaria rhineophylla showed activity against both bacterial and fungal strains,indicating their broad spectrum of activity.Conclusions:The results revealed that the ethanol extracts of 30 plants out of the selected 58 possess significant antimicrobial activities.It is interesting to note that the findings from the current study are consistent with the traditional use.A clear correlation has also been found between the antimicrobial activity and the flavonoid content of the plant extracts which is in agreement with the literature.Hence.the results presented here can be used to guide the selection of potential plant species for the isolation and structure elucidation of novel antimicrobial compounds in order to establish the structure-activity relationship.This in turn is expected to lead the way to the discovery of novel antimicrobial agents for therapeutic use.
基金National Council for Scientific and Technological Development (CNPq No.248705/2013-0)
文摘Green tea has been an important beverage for humans since ancient times, widely consumed and considered to have health benefits by traditional medicine in Asian countries. Green tea phenolic compounds are predominately composed of catechin derivatives, although other compounds such as flavonols and phenolic acids are also present in lower proportion. The bioactivity exerted by these compounds has been associated with reduced risk of severe illnesses such as cancer, cardiovascular and neurodegenerative diseases. Particularly, epigallocatechin gallate has been implicated in alteration mechanisms with protective effect in these diseases as indicated by several studies about the effect of green tea consumption and mechanistic explanation through in vitro and in vivo experiments. The biological activity of green tea phenolic compounds also promotes a protective effect by antioxidant mechanisms in biological and food systems, preventing the oxidative damage by acting over either precursors or reactive species. Extraction of phenolic compounds influences the antioxidant activity and promotes adequate separation from green tea leaves to enhance the yield and/or antioxidant activity. Application of green tea phenolic compounds is of great interest because the antioxidant status of the products is enhanced and provides the product with additional antioxidant activity or reduces the undesirable changes of oxidative reactions while processing or storing food.In this scenario, meat and meat products are greatly influenced by oxidative deterioration and microbial spoilage, leading to reduced shelf life. Green tea extracts rich in phenolic compounds have been applied to increase shelf life with comparable effect to synthetic compounds, commonly used by food industry. Green tea has great importance in general health in technological application, however more studies are necessary to elucidate the impact in pathways related to other diseases and food applications.
