In this work, Staphylococcus epidermidis (S. epidermidis) was used to prepare the fermentation broths with antioxidant activity. Through the optimization of the carbon source, three kinds of S. epidermidis fermentatio...In this work, Staphylococcus epidermidis (S. epidermidis) was used to prepare the fermentation broths with antioxidant activity. Through the optimization of the carbon source, three kinds of S. epidermidis fermentation broth were obtained and designated as SFB, Gly-SFB, and Glu-SFB, which were cultivated in beef protein medium and the beef protein medium supplemented with glycerol or glucose, respectively. The differences in antioxidant efficacy of SFB, Gly-SFB and Glu-SFB were investigated by evaluating intracellular ROS fluorescence intensity, SOD enzyme activity and MDA concentration. Gly-SFB and Glu-SFB exhibited a greater capacity to eliminate ROS as compared to that of SFB. The intracellular SOD enzyme activity increased as the concentrations of SFB and Gly-SFB increased. Nevertheless, the intracellular SOD enzyme activity was the highest after the treatment with Glu-SFB at the low concentrations. The intracellular MDA content reached a lower value after the treatment with Gly-SFB and Glu-SFB at lower concentrations, which was opposite to the case after the treatment with SFB. WB indicated that the S. epidermidis fermentation broth regulated the expression of relevant proteins in the Nrf2-Keap1 signaling pathway to exhibit the antioxidant effects. This indicates that the S. epidermidis fermentation broth promotes the expression of relevant proteins in the Nrf2-Keap1 signaling pathway, consequently, antioxidant benefits were exerted. The fermentation broth that were prepared by incorporating glycerol or glucose into the culture medium can augment their antioxidant activity.展开更多
Objectives:Limosilactobacillus reuteri is a beneficial Lactobacillus widely used in foods and supplements to promote overall health.Some studies also suggest it supports skin health and prevents allergies and cardiova...Objectives:Limosilactobacillus reuteri is a beneficial Lactobacillus widely used in foods and supplements to promote overall health.Some studies also suggest it supports skin health and prevents allergies and cardiovascular disease.However,research on its skin-protective effects against photoaging has not been conducted.This study evaluated the potential of culture broths fromthree L.reuteri strains(DS0333,DS0384,and DS0385)to inhibit skin photoaging.Methods:To assess their anti-photoaging potential,the culture broths were examined for antioxidant capacity,melanin inhibition,and collagen synthesis promotion.Radical scavenging activity was tested using 2,2-diphenyl-1-picrylhydrazyl(DPPH)and 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid)(ABTS)assays.The biosynthetic activity of melanin and associated protein markers involved in melanogenesis was examined in a B16F10 mouse melanoma model.Type I procollagen synthesis and matrix metalloproteinase-1(MMP-1)inhibition were evaluated in ultraviolet B(UVB)-damaged human dermal fibroblasts(HDFs).Results:The culture broths exhibited concentrationdependent antioxidant activity and significantly suppressed melanin synthesis triggered byα-melanocyte-stimulating hormone(α-MSH).Transcription factors involved inmelanogenesis,namelymicrophthalmia-associated transcription factor(MITF),tyrosinase-related protein 1(TRP-1),and 2(TRP-2),were significantly downregulated following treatment.Treatment with culture broths also enhanced type I procollagen production and inhibited MMP-1 activity and protein expression in UVB-exposed HDFs.Among the strains,DS0333 demonstrated the strongest efficacy and was further investigated.It enhanced the proliferation of skin cells and attenuated the levels of age-associated markers such as MMP-1,mitogen-activated protein kinase(MAPK),and activator protein 1(AP-1).High-performance liquid chromatography(HPLC)analysis identified phenyllactic acid(PLA)as the predominant active compound.Conclusions:These results indicate that DS0333 culture broth exhibits strong anti-aging effects and can be applied in functional cosmetics aimed at promoting skin health.展开更多
BACKGROUND The unique survival environment of Helicobacter pylori(H.pylori)presents challenges in establishing appropriate in vitro culture conditions.The fastidious nature of H.pylori and its relatively low growth ra...BACKGROUND The unique survival environment of Helicobacter pylori(H.pylori)presents challenges in establishing appropriate in vitro culture conditions.The fastidious nature of H.pylori and its relatively low growth rate emphasize the need for customized culture conditions,which are essential for both research and clinical applications.AIM To identify the optimal liquid culture medium for H.pylori using both reference and clinical strains.METHODS Nine H.pylori strains were incubated in 10 different broth media commonly used for bacterial cultures under microaerophilic conditions.Bacterial concentrations were estimated using serial dilutions and the pour plate method.A range of H.pylori initial inoculum concentrations was tested for each strain.For growth evaluation,optical density at 600 nm was measured at 24,48,and 72 hours.The growth trends of H.pylori were compared among strains and media.RESULTS All H.pylori strains grew successfully over time,regardless of the initial inoculum concentration.The specific growth trends and the broth that yielded the highest optical density value at each time point varied with strain.The reference strains(H.pylori 26695,ATCC 43504,and J99)consistently exhibited robust growth,whereas the clinical strains displayed distinct media preferences.Overall,bacterial growth was higher in chopped meat carbohydrate broth,Columbia broth,and fastidious anaerobe broth than in Brucella broth after 72 hours.CONCLUSION Chopped meat carbohydrate broth was the most effective for H.pylori liquid culture,and Columbia broth and fastidious anaerobe broth also supported greater growth than Brucella broth.展开更多
Aim A liquid chromatographic method for the determination ofcandicidin/FR-008 and related components in fermentation broth has been developed. Methods Therewere four major components in the candicidin/FR-008 complex, ...Aim A liquid chromatographic method for the determination ofcandicidin/FR-008 and related components in fermentation broth has been developed. Methods Therewere four major components in the candicidin/FR-008 complex, which were separated by HPLC under thefollowing conditions: SB-C8 column (4.6 mm x 250 mm, 5 μm) was used, the mobile phase consisted ofacetonitrileam-monium acteate (20 mmol·L^(-1) , pH 4.0) (40:60, V/V) , with a flow rate of 1 .0mL·min^(-1) , the UV detection wavelength was 380 nm, and the whole process was performed at 25℃ .Results The linearity was obtained in the range of 6.25 - 500 μg· mL^(-1) candicidin/FR-008 withthe regression equation of Y = 20 461 x + 30 748 and the correlation coefficient of 0.999 1. Theinstrument precision was 1.84% and the method precision was 3.8%. Conclusion This method isaccurate, rapid and simple; it can be used for determination of candicidin/FR-008 and relatedcomponents in fermentation broth.展开更多
目的建立一种利用菌液吸收法去除A、C、Y、W135群脑膜炎球菌抗血清交叉反应的纯化方法,并验证其在多糖结合疫苗检测中的适用性。方法将A、C、Y、W135群脑膜炎球菌分别经耳缘静脉注射免疫新西兰兔,每群2只(雌雄各半),首周隔天免疫1次,共...目的建立一种利用菌液吸收法去除A、C、Y、W135群脑膜炎球菌抗血清交叉反应的纯化方法,并验证其在多糖结合疫苗检测中的适用性。方法将A、C、Y、W135群脑膜炎球菌分别经耳缘静脉注射免疫新西兰兔,每群2只(雌雄各半),首周隔天免疫1次,共免疫3次,连续免疫4周,制备基础抗血清;采用异群菌液反复吸收法进行抗血清的去交叉纯化,ELISA法比较纯化前后抗血清与异群多糖的交叉反应率,火箭电泳和速率比浊法进一步佐证血清的特异性。对建立的方法进行特异性、专属性、重复性、耐用性及稳定性验证。结果未纯化抗血清存在明显交叉反应,最高交叉率达16.25%。经菌液吸收处理后,A、C、Y、W135群抗血清与异群多糖的交叉反应率均显著下降至2%以下,且保留了较高的特异性抗体几何平均滴度(geometric mean titer,GMT);火箭电泳与速率比浊法检测结果均证实纯化后血清无交叉沉淀产生。纯化后血清特异性良好,不与其他群结合物多糖抗原发生明显的交叉反应,且专属性较高;各群血清检测的组内CV为0.96%~6.10%,组间CV为3.21%~6.18%,均<15%;在不同抗原浓度(5~15μg/mL)下,测定结果的相对误差(relative error,RE)值均小于8%,耐用性良好;血清库在360 d观察期内效价稳定,无显著差异。结论建立的菌液吸收纯化方法能高效去除A、C、Y、W135群脑膜炎球菌抗血清间的交叉反应,制备的抗血清具有高特异性,良好的精密度和稳定性,可作为脑膜炎球菌多糖结合疫苗质量控制的关键检测试剂。展开更多
To improve the nutritional value and the palatability of air-dried rice straw, culture broth of the lactic acid bacteria community SFC-2 was used to examine the effects of two different treatments, fermentation and ad...To improve the nutritional value and the palatability of air-dried rice straw, culture broth of the lactic acid bacteria community SFC-2 was used to examine the effects of two different treatments, fermentation and adsorption. Air-dried and chopped rice straw was treated with either fermentation for 30 d after adding 1.5 L nutrient solution（50 m L inocula L–1, 1.2×1012 CFU m L–1 inocula） kg–1 straw dry matter, or spraying a large amount of culture broth（1.5 L kg–1 straw dry matter, 1.5×1011 CFU m L–1 culture broth） on the straw and allowing it to adsorb for 30 min. The feed quality and aerobic stability of the resulting forage were examined. Both treatments improved the feed quality of rice straw, and adsorption was better than fermentation for preserving nutrients and improving digestibility, as evidenced by higher dry matter（DM） and crude protein（CP） concentrations, lower neutral detergent fiber（NDF）, acid detergent fiber（ADF） and NH3-N concentrations, as well as higher lactic acid production and in vitro digestibility of DM（IVDMD）. The aerobic stability of the adsorbed straw and the fermented straw was 392 and 480 h, respectively. After being exposed to air, chemical components and microbial community of the fermented straw were more stable than the adsorbed straw.展开更多
AIM： Methicillin-resistant Staphylococcus aureus （MRSA） is a pathogenic bacterium that causes both hospital- and community-acquired infections, and for which single-drug treatments are becoming less efficient. Rhiz...AIM： Methicillin-resistant Staphylococcus aureus （MRSA） is a pathogenic bacterium that causes both hospital- and community-acquired infections, and for which single-drug treatments are becoming less efficient. Rhizoma coptidis has been used for more than two thousand years in China to treat diarrhea, fever, and jaundice. In this study, the anti-MRSA activity of Rhizoma coptidis is examined and its effective components sought. METHODS： The mecA and norA genes were determined by PCR amplification and sequencing. Drug susceptibility of Staphylococcus aureus ATCC43300 was performed using the VITEK2 compact system. The chemical fingerprint of Rhizoma coptidis was investigated using HPLC and preparative liquid chromatography, and the anti-MRSA activity was determined using an improved broth microdilution method. RESULTS： The drug susceptibility test revealed that the penicillin-binding protein phenotype of the strain changed in comparison to penicillin-sensitive Staphylococcus aureus. Ten batches of Rhizoma coptidis showed anti-MRSA activity on the norA-negative Staphylococcus aureus strain, as well as the strain that contained a norA gene. The spectrum-effect relationship revealed that the berberine alkaloids were the effective components, within which berberine, coptisine, palmatine, epiberberine,, and jatrorrhizine were the major components. CONCLUSION： This study lays a foundation for in vivo studies of Rhizoma eoptidis and for the development of multi-component drugs.展开更多
To investigate the effects of thyme(Thymus vulgaris L.)addition on the flavor modification of mutton broth during boiling,three mutton-broth samples with various thyme contents 0.06%(S1),0.30%(S2),and1.50%(S3)were ana...To investigate the effects of thyme(Thymus vulgaris L.)addition on the flavor modification of mutton broth during boiling,three mutton-broth samples with various thyme contents 0.06%(S1),0.30%(S2),and1.50%(S3)were analyzed and compared,without thyme as control(0.00%,S0).The meaty,fatty,pastoral flavor and spicy were chosen as sensory attributes to evaluate the flavor of the mutton-broth samples.Sensory results were significantly different(P<0.001),with S2 having the optimum overall acceptability.A total of 99 volatile compounds were identified by gas chromatography-mass spectrometry,among which19 compounds were considered as the odor-active compounds according to their odor activity values.Significant changes(P<0.05)appeared in most volatiles in S0 with thyme addition,especially aldehydes.Free fatty acids(FFAs)were also identified,and all of them significantly increased with increased thyme(P<0.05).Correlation analysis of odor-active compounds,FFAs,and sensory attributes through partial least squares regression indicated the important volatiles and FFAs remarkably contributed to the mutton broth samples,and further confirmed that the 0.30%of thyme may be a desirable addition amount for the sensory characteristics of mutton broth.展开更多
[Objective] The aim was to study if the fermentation broth of Kombucha has protein with antimicrobial activity. [Method] The effects of different cultivation time on cell concentration, pH, total protein concentration...[Objective] The aim was to study if the fermentation broth of Kombucha has protein with antimicrobial activity. [Method] The effects of different cultivation time on cell concentration, pH, total protein concentration and inhibition zone were studied. The fermentation broth of Kombucha on the sixth day was adjusted to different pH. Fermentation broth treated with protease was put into the plates of Escherichia co/i, Bacillus cereue and Staphylococcus aureus as control, as well as ampenicilin. The zone of broth inhibition was measured. [ Result] The concentration of general protein was of positive relevance to the antimicrobial activity of Kombucha fermentation broth. The zone of inhibition decreased with rising pH and was the lowest when pH was 7. Later, as pH increasing, it enlarged. The inhibition effect of processed protease reduced remarkably. [ Conclusion] The fermentation broth of Kombucha revealed antimicrobial proteins.展开更多
The feasibility of ethanol separation from ethanol-water solution saturated with glucose by gas strippingis showil theoretically and experimentally. The effects of glucose on the saturated vapor pressure of ethanol, a...The feasibility of ethanol separation from ethanol-water solution saturated with glucose by gas strippingis showil theoretically and experimentally. The effects of glucose on the saturated vapor pressure of ethanol, and thatof operating temperature and gas stripping flow rates, K/G, on Stripping result are discussed.展开更多
Purpose: Diet and eating habits are major risk factors for the health and the development of disease, such as, for example, metabolic disorder leading to cardiovascular pathology and cancer, decreased immunity exposin...Purpose: Diet and eating habits are major risk factors for the health and the development of disease, such as, for example, metabolic disorder leading to cardiovascular pathology and cancer, decreased immunity exposing to infections. This study of the physico-chemical and nutritional properties of a soumara-based food broth was carried out with the aim of promoting the consumption of organic broth made from nere seeds (soumara). That is to alleviate certain metabolic diseases, which is a matter of food safety, and also to limit the risk for the health about the consumption of some cooking stocks on the market. Methods: Several natural ingredients such as nere seeds (soumara), ginger, black pepper, parsley and garlic were used to create a nere-based stock. All these ingredients were freeze-dried and the powder obtained was used to make the broth, regarding their physical and chemical properties. Results: The broth had a good protein content of 17.41 ± 0.367 g/100g, a lipid content of 16.80 ± 0.08 g/100g and a fiber content of 8.66 ± 0.04 g/100g. In terms of nutritional values, the broth showed good levels of calcium 184.21 ± 0.09 mg/100g, potassium 50.04 ± 1.45 mg/100g and iron and zinc. In terms of antioxidant activity, the broth also showed good antioxidant activity. Conclusion: Regarding the properties of our food broth, whose composition is based on natural ingredients, could be recommended for consumption and, its properties, could play an important role in preventing and combating certain metabolic diseases.展开更多
The aim of this study was to design a new emulsion liquid membrane(ELM)system for the separation of succinic acid from aqueous solutions.The concentration of succinic acid varied from 20 to 60 mmol·L^(-1).The pre...The aim of this study was to design a new emulsion liquid membrane(ELM)system for the separation of succinic acid from aqueous solutions.The concentration of succinic acid varied from 20 to 60 mmol·L^(-1).The prepared ELM system includes tributylamine(TBA)as a carrier,commercial kerosene as a solvent,Span 80 as a surfactant,and Na2CO3as a stripping agent.In order to control the membrane swelling,different values of cyclohexanone were added to the membrane phase.The effect of various empirical variables on the extraction of the succinic acid such as acid concentration in the feed solution,initial feed concentration,carrier concentration,the stirring speed of the extraction,Na2CO3,surfactant,and cyclohexanone concentrations,and treat ratio in the ELM system.The best result was obtained when TBA was used as the carrier.The final acid extraction efficiency was independent of pH variations of the aqueous feed solution.The extraction of succinic acid solution with a concentration of 40 mmol·L^(-1)was improved by increasing the treat ratio 1:7-1:3,stripping phase concentration 0.5-1.5 mol·L^(-1),stirring speed 300-500 r·min^(-1)and cyclohexanone concentration in the membrane phase 1.2-1.6 mol·L^(-1).No considerable effect on the extraction rate was observed for the carrier concentration in the membrane phase.But,the surfactant concentration in the feed phase showed a dual effect on the extraction efficiency.展开更多
文摘In this work, Staphylococcus epidermidis (S. epidermidis) was used to prepare the fermentation broths with antioxidant activity. Through the optimization of the carbon source, three kinds of S. epidermidis fermentation broth were obtained and designated as SFB, Gly-SFB, and Glu-SFB, which were cultivated in beef protein medium and the beef protein medium supplemented with glycerol or glucose, respectively. The differences in antioxidant efficacy of SFB, Gly-SFB and Glu-SFB were investigated by evaluating intracellular ROS fluorescence intensity, SOD enzyme activity and MDA concentration. Gly-SFB and Glu-SFB exhibited a greater capacity to eliminate ROS as compared to that of SFB. The intracellular SOD enzyme activity increased as the concentrations of SFB and Gly-SFB increased. Nevertheless, the intracellular SOD enzyme activity was the highest after the treatment with Glu-SFB at the low concentrations. The intracellular MDA content reached a lower value after the treatment with Gly-SFB and Glu-SFB at lower concentrations, which was opposite to the case after the treatment with SFB. WB indicated that the S. epidermidis fermentation broth regulated the expression of relevant proteins in the Nrf2-Keap1 signaling pathway to exhibit the antioxidant effects. This indicates that the S. epidermidis fermentation broth promotes the expression of relevant proteins in the Nrf2-Keap1 signaling pathway, consequently, antioxidant benefits were exerted. The fermentation broth that were prepared by incorporating glycerol or glucose into the culture medium can augment their antioxidant activity.
基金supported by a Korea Innovation Foundation(INNOPOLIS)grant funded by the Korean government(Ministry of Science and ICT)through a science and technology project that opens the future of the region(grant number:2021-DD-UP-0380).
文摘Objectives:Limosilactobacillus reuteri is a beneficial Lactobacillus widely used in foods and supplements to promote overall health.Some studies also suggest it supports skin health and prevents allergies and cardiovascular disease.However,research on its skin-protective effects against photoaging has not been conducted.This study evaluated the potential of culture broths fromthree L.reuteri strains(DS0333,DS0384,and DS0385)to inhibit skin photoaging.Methods:To assess their anti-photoaging potential,the culture broths were examined for antioxidant capacity,melanin inhibition,and collagen synthesis promotion.Radical scavenging activity was tested using 2,2-diphenyl-1-picrylhydrazyl(DPPH)and 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid)(ABTS)assays.The biosynthetic activity of melanin and associated protein markers involved in melanogenesis was examined in a B16F10 mouse melanoma model.Type I procollagen synthesis and matrix metalloproteinase-1(MMP-1)inhibition were evaluated in ultraviolet B(UVB)-damaged human dermal fibroblasts(HDFs).Results:The culture broths exhibited concentrationdependent antioxidant activity and significantly suppressed melanin synthesis triggered byα-melanocyte-stimulating hormone(α-MSH).Transcription factors involved inmelanogenesis,namelymicrophthalmia-associated transcription factor(MITF),tyrosinase-related protein 1(TRP-1),and 2(TRP-2),were significantly downregulated following treatment.Treatment with culture broths also enhanced type I procollagen production and inhibited MMP-1 activity and protein expression in UVB-exposed HDFs.Among the strains,DS0333 demonstrated the strongest efficacy and was further investigated.It enhanced the proliferation of skin cells and attenuated the levels of age-associated markers such as MMP-1,mitogen-activated protein kinase(MAPK),and activator protein 1(AP-1).High-performance liquid chromatography(HPLC)analysis identified phenyllactic acid(PLA)as the predominant active compound.Conclusions:These results indicate that DS0333 culture broth exhibits strong anti-aging effects and can be applied in functional cosmetics aimed at promoting skin health.
基金Supported by the Bio&Medical Technology Development Program of the National Research Foundation Funded by the Korean Government(MSIT),No.RS-2023-00223501Hallym University Research Fund.
文摘BACKGROUND The unique survival environment of Helicobacter pylori(H.pylori)presents challenges in establishing appropriate in vitro culture conditions.The fastidious nature of H.pylori and its relatively low growth rate emphasize the need for customized culture conditions,which are essential for both research and clinical applications.AIM To identify the optimal liquid culture medium for H.pylori using both reference and clinical strains.METHODS Nine H.pylori strains were incubated in 10 different broth media commonly used for bacterial cultures under microaerophilic conditions.Bacterial concentrations were estimated using serial dilutions and the pour plate method.A range of H.pylori initial inoculum concentrations was tested for each strain.For growth evaluation,optical density at 600 nm was measured at 24,48,and 72 hours.The growth trends of H.pylori were compared among strains and media.RESULTS All H.pylori strains grew successfully over time,regardless of the initial inoculum concentration.The specific growth trends and the broth that yielded the highest optical density value at each time point varied with strain.The reference strains(H.pylori 26695,ATCC 43504,and J99)consistently exhibited robust growth,whereas the clinical strains displayed distinct media preferences.Overall,bacterial growth was higher in chopped meat carbohydrate broth,Columbia broth,and fastidious anaerobe broth than in Brucella broth after 72 hours.CONCLUSION Chopped meat carbohydrate broth was the most effective for H.pylori liquid culture,and Columbia broth and fastidious anaerobe broth also supported greater growth than Brucella broth.
文摘Aim A liquid chromatographic method for the determination ofcandicidin/FR-008 and related components in fermentation broth has been developed. Methods Therewere four major components in the candicidin/FR-008 complex, which were separated by HPLC under thefollowing conditions: SB-C8 column (4.6 mm x 250 mm, 5 μm) was used, the mobile phase consisted ofacetonitrileam-monium acteate (20 mmol·L^(-1) , pH 4.0) (40:60, V/V) , with a flow rate of 1 .0mL·min^(-1) , the UV detection wavelength was 380 nm, and the whole process was performed at 25℃ .Results The linearity was obtained in the range of 6.25 - 500 μg· mL^(-1) candicidin/FR-008 withthe regression equation of Y = 20 461 x + 30 748 and the correlation coefficient of 0.999 1. Theinstrument precision was 1.84% and the method precision was 3.8%. Conclusion This method isaccurate, rapid and simple; it can be used for determination of candicidin/FR-008 and relatedcomponents in fermentation broth.
文摘目的建立一种利用菌液吸收法去除A、C、Y、W135群脑膜炎球菌抗血清交叉反应的纯化方法,并验证其在多糖结合疫苗检测中的适用性。方法将A、C、Y、W135群脑膜炎球菌分别经耳缘静脉注射免疫新西兰兔,每群2只(雌雄各半),首周隔天免疫1次,共免疫3次,连续免疫4周,制备基础抗血清;采用异群菌液反复吸收法进行抗血清的去交叉纯化,ELISA法比较纯化前后抗血清与异群多糖的交叉反应率,火箭电泳和速率比浊法进一步佐证血清的特异性。对建立的方法进行特异性、专属性、重复性、耐用性及稳定性验证。结果未纯化抗血清存在明显交叉反应,最高交叉率达16.25%。经菌液吸收处理后,A、C、Y、W135群抗血清与异群多糖的交叉反应率均显著下降至2%以下,且保留了较高的特异性抗体几何平均滴度(geometric mean titer,GMT);火箭电泳与速率比浊法检测结果均证实纯化后血清无交叉沉淀产生。纯化后血清特异性良好,不与其他群结合物多糖抗原发生明显的交叉反应,且专属性较高;各群血清检测的组内CV为0.96%~6.10%,组间CV为3.21%~6.18%,均<15%;在不同抗原浓度(5~15μg/mL)下,测定结果的相对误差(relative error,RE)值均小于8%,耐用性良好;血清库在360 d观察期内效价稳定,无显著差异。结论建立的菌液吸收纯化方法能高效去除A、C、Y、W135群脑膜炎球菌抗血清间的交叉反应,制备的抗血清具有高特异性,良好的精密度和稳定性,可作为脑膜炎球菌多糖结合疫苗质量控制的关键检测试剂。
基金supported by the National Key Technology Research and Development Program of China during the 12th Five-Year Plan period (2012BAD14B01)the Special Fund for Agro-Scientific Research in the Public Interest, China (201303080)
文摘To improve the nutritional value and the palatability of air-dried rice straw, culture broth of the lactic acid bacteria community SFC-2 was used to examine the effects of two different treatments, fermentation and adsorption. Air-dried and chopped rice straw was treated with either fermentation for 30 d after adding 1.5 L nutrient solution（50 m L inocula L–1, 1.2×1012 CFU m L–1 inocula） kg–1 straw dry matter, or spraying a large amount of culture broth（1.5 L kg–1 straw dry matter, 1.5×1011 CFU m L–1 culture broth） on the straw and allowing it to adsorb for 30 min. The feed quality and aerobic stability of the resulting forage were examined. Both treatments improved the feed quality of rice straw, and adsorption was better than fermentation for preserving nutrients and improving digestibility, as evidenced by higher dry matter（DM） and crude protein（CP） concentrations, lower neutral detergent fiber（NDF）, acid detergent fiber（ADF） and NH3-N concentrations, as well as higher lactic acid production and in vitro digestibility of DM（IVDMD）. The aerobic stability of the adsorbed straw and the fermented straw was 392 and 480 h, respectively. After being exposed to air, chemical components and microbial community of the fermented straw were more stable than the adsorbed straw.
基金supported by the National Natural Science Foundation of China(No.81073043)
文摘AIM： Methicillin-resistant Staphylococcus aureus （MRSA） is a pathogenic bacterium that causes both hospital- and community-acquired infections, and for which single-drug treatments are becoming less efficient. Rhizoma coptidis has been used for more than two thousand years in China to treat diarrhea, fever, and jaundice. In this study, the anti-MRSA activity of Rhizoma coptidis is examined and its effective components sought. METHODS： The mecA and norA genes were determined by PCR amplification and sequencing. Drug susceptibility of Staphylococcus aureus ATCC43300 was performed using the VITEK2 compact system. The chemical fingerprint of Rhizoma coptidis was investigated using HPLC and preparative liquid chromatography, and the anti-MRSA activity was determined using an improved broth microdilution method. RESULTS： The drug susceptibility test revealed that the penicillin-binding protein phenotype of the strain changed in comparison to penicillin-sensitive Staphylococcus aureus. Ten batches of Rhizoma coptidis showed anti-MRSA activity on the norA-negative Staphylococcus aureus strain, as well as the strain that contained a norA gene. The spectrum-effect relationship revealed that the berberine alkaloids were the effective components, within which berberine, coptisine, palmatine, epiberberine,, and jatrorrhizine were the major components. CONCLUSION： This study lays a foundation for in vivo studies of Rhizoma eoptidis and for the development of multi-component drugs.
基金supported by the National key research and development program(grant number 2016YFD0400705)。
文摘To investigate the effects of thyme(Thymus vulgaris L.)addition on the flavor modification of mutton broth during boiling,three mutton-broth samples with various thyme contents 0.06%(S1),0.30%(S2),and1.50%(S3)were analyzed and compared,without thyme as control(0.00%,S0).The meaty,fatty,pastoral flavor and spicy were chosen as sensory attributes to evaluate the flavor of the mutton-broth samples.Sensory results were significantly different(P<0.001),with S2 having the optimum overall acceptability.A total of 99 volatile compounds were identified by gas chromatography-mass spectrometry,among which19 compounds were considered as the odor-active compounds according to their odor activity values.Significant changes(P<0.05)appeared in most volatiles in S0 with thyme addition,especially aldehydes.Free fatty acids(FFAs)were also identified,and all of them significantly increased with increased thyme(P<0.05).Correlation analysis of odor-active compounds,FFAs,and sensory attributes through partial least squares regression indicated the important volatiles and FFAs remarkably contributed to the mutton broth samples,and further confirmed that the 0.30%of thyme may be a desirable addition amount for the sensory characteristics of mutton broth.
基金Supported by Scientific Research Fund of Beijing Educational DepartmentBeijing Higher School Personnel Teaching Program
文摘[Objective] The aim was to study if the fermentation broth of Kombucha has protein with antimicrobial activity. [Method] The effects of different cultivation time on cell concentration, pH, total protein concentration and inhibition zone were studied. The fermentation broth of Kombucha on the sixth day was adjusted to different pH. Fermentation broth treated with protease was put into the plates of Escherichia co/i, Bacillus cereue and Staphylococcus aureus as control, as well as ampenicilin. The zone of broth inhibition was measured. [ Result] The concentration of general protein was of positive relevance to the antimicrobial activity of Kombucha fermentation broth. The zone of inhibition decreased with rising pH and was the lowest when pH was 7. Later, as pH increasing, it enlarged. The inhibition effect of processed protease reduced remarkably. [ Conclusion] The fermentation broth of Kombucha revealed antimicrobial proteins.
文摘The feasibility of ethanol separation from ethanol-water solution saturated with glucose by gas strippingis showil theoretically and experimentally. The effects of glucose on the saturated vapor pressure of ethanol, and thatof operating temperature and gas stripping flow rates, K/G, on Stripping result are discussed.
文摘Purpose: Diet and eating habits are major risk factors for the health and the development of disease, such as, for example, metabolic disorder leading to cardiovascular pathology and cancer, decreased immunity exposing to infections. This study of the physico-chemical and nutritional properties of a soumara-based food broth was carried out with the aim of promoting the consumption of organic broth made from nere seeds (soumara). That is to alleviate certain metabolic diseases, which is a matter of food safety, and also to limit the risk for the health about the consumption of some cooking stocks on the market. Methods: Several natural ingredients such as nere seeds (soumara), ginger, black pepper, parsley and garlic were used to create a nere-based stock. All these ingredients were freeze-dried and the powder obtained was used to make the broth, regarding their physical and chemical properties. Results: The broth had a good protein content of 17.41 ± 0.367 g/100g, a lipid content of 16.80 ± 0.08 g/100g and a fiber content of 8.66 ± 0.04 g/100g. In terms of nutritional values, the broth showed good levels of calcium 184.21 ± 0.09 mg/100g, potassium 50.04 ± 1.45 mg/100g and iron and zinc. In terms of antioxidant activity, the broth also showed good antioxidant activity. Conclusion: Regarding the properties of our food broth, whose composition is based on natural ingredients, could be recommended for consumption and, its properties, could play an important role in preventing and combating certain metabolic diseases.
文摘The aim of this study was to design a new emulsion liquid membrane(ELM)system for the separation of succinic acid from aqueous solutions.The concentration of succinic acid varied from 20 to 60 mmol·L^(-1).The prepared ELM system includes tributylamine(TBA)as a carrier,commercial kerosene as a solvent,Span 80 as a surfactant,and Na2CO3as a stripping agent.In order to control the membrane swelling,different values of cyclohexanone were added to the membrane phase.The effect of various empirical variables on the extraction of the succinic acid such as acid concentration in the feed solution,initial feed concentration,carrier concentration,the stirring speed of the extraction,Na2CO3,surfactant,and cyclohexanone concentrations,and treat ratio in the ELM system.The best result was obtained when TBA was used as the carrier.The final acid extraction efficiency was independent of pH variations of the aqueous feed solution.The extraction of succinic acid solution with a concentration of 40 mmol·L^(-1)was improved by increasing the treat ratio 1:7-1:3,stripping phase concentration 0.5-1.5 mol·L^(-1),stirring speed 300-500 r·min^(-1)and cyclohexanone concentration in the membrane phase 1.2-1.6 mol·L^(-1).No considerable effect on the extraction rate was observed for the carrier concentration in the membrane phase.But,the surfactant concentration in the feed phase showed a dual effect on the extraction efficiency.
