The antagonistic activity of Lactobacillus acidophilus KLDS1.0901, KLDS1.0902, KLDSI.1003 and NCFM against Escherichia coli O157 ： H7 were investigated in this study. The culture supematants of all the L. acidophilus...The antagonistic activity of Lactobacillus acidophilus KLDS1.0901, KLDS1.0902, KLDSI.1003 and NCFM against Escherichia coli O157 ： H7 were investigated in this study. The culture supematants of all the L. acidophilus stains showed high bacteriostatic activities against E. coli O 157 ： H7 and the bacteriostatic substances of their Cell-Free Supernatants （CFS） were preliminarily determined from organic acids. The bacteriostatic activity from CFS or viable L. acidophilus against E. coli O157 ： H7 was also assessed by using co-incubation methods, CFS had high bactericidal activity against E. coli O157 ： H7, no viable E. coli O157 ： H7 was detected when 5×10^7 CfU ofE. coli O157 ： H7 was added to 5 mL of CFS and incubated at 37℃ for 2 h. However, L. acidophilus themselves had no bacteriostatic activity after directly contacted with E. coli O157 ： H7. The inhibition E. coli O157 ： H7 adhesion and colonization of L. acidophilus were also investigated based on competition, exclusion and displacement assays. L. acidophilus KLDS1.0901, KLDSI.1003 and NCFM strains were effective to displace E. coli O157 ： H7 from a Caco-2 cell layer in competition and exclusion assays. However, in displacement assay, all of the strains showed no significant antagonistic activities. Meanwhile, the probiotic potential of L. acidophilus strains was investigated based on adhesion assay to Caco-2 cells and anti- inflammatory effects by IL-8 produced in Caco-2 cells. The adhesion ability and anti-inflammatory effects of L. acidophilus strains showed a strain-dependent manner. In general, L. acidophilus KLDS 1.0901 and NCFM showed better probiotic potential than KLDS1.0902 and KLDSI.1003. Thus, the use ofL. acidophilus KLDS1.0901 and NCFM to prevent or treat of diseases associated induced E. coli O157 ： H7 in vivo was suggested.展开更多
Prediction of antagonistic activity of <em>β</em>-carboline and its thirteen derivatives has been made using topological descriptors viz, connectivity index, and kappa shape index of different orders. For...Prediction of antagonistic activity of <em>β</em>-carboline and its thirteen derivatives has been made using topological descriptors viz, connectivity index, and kappa shape index of different orders. For evaluation of values of descriptor, molecular modeling and geometry optimization of all the compounds were carried out with CAChe Pro software by opting semiempirical PM3 method using MOPAC 2002. For prediction of activity multiple linear regression analysis (MLR) was performed. MLR analysis has been made by Project Leader Software associated with CAChe by using the above descriptors as independent variables and biological activity as dependent variables. We were performed leave-one-out methods and the result reflected a direct relationship between biological activity and connectivity index of zero order, while indirect relationship with connectivity index of second order and thus connectivity index is a reliable descriptor to predict the biological activity of <em>β</em>-carboline and its various derivatives.展开更多
A strain LHB02 with strong antibacterial activity against some aquatic pathogens was screened from the coastal marine sediment in Fujian province, China. LHB02 was identified as Bacillus subtilis, based on its 16S rRN...A strain LHB02 with strong antibacterial activity against some aquatic pathogens was screened from the coastal marine sediment in Fujian province, China. LHB02 was identified as Bacillus subtilis, based on its 16S rRNA sequence, together with the morphological, physiological and biochemical characteristics. The antagonistic activity of strain LHB02 and its optimal fermentation conditions were also investigated. The results showed that LHB02 had strong antagonistic activity against 3 species of vibrios： Vibrio harveyi,Vibrio alginolyticus and Vibrio anguillarum, and the optimum fermentation conditions for the strain LHB02 were as follows： KB culture medium （peptone 20 g, glycerol 10 mL, K2HPO4 1.5 g, MgSO 4 .7H2O 1.5 g, H2O 1 000 mL）; temperature, 28 ℃; pH ,7.0; culture time, 36 h; and inoculation amount, 1.5% （v/v）.展开更多
[ Objective] The paper was to screen the antagonistic strain against Phytophthora sojae with biocontrol potential, and provide basis for searching control measures and designing new control strategies against P. sojae...[ Objective] The paper was to screen the antagonistic strain against Phytophthora sojae with biocontrol potential, and provide basis for searching control measures and designing new control strategies against P. sojae. [ Method] The rhizosphere soil of soybean was collected from three different places in Heilongjiang Province, and various soil microorganisms were isolated. Dual culture method was used to screen the microorganism with antagonistic effect against P. sojae. On this basis, the growth inhibition rate of the microorganism with stronger antagonistic effect against P. sojae was determined, and its control effect against P. sojae was also measured. [ Result] A strain of bacterium with relatively good antagonistic effect was isolated from soil, and named as strain B048. Dual test showed that the growth inhibition rate of antagonistic bacterium 11048 against P. sojac reached 97.5%. Antagonistic endurance tests showed that the width of inhibition zone was still 20.0 mm after dual culture with P. sojac for21 d. In potting experiment, the control effect of B048 against P. sojae was 100%. The antagonistic bacterium was primarily identified to be Bacillus pumilus through morphology and 16S rDNA sequence analysis. [Condusion] The antagonistic bacterium B048 had good prospect to be developed as the biocontrol bacterium against P. sojae.展开更多
[ Objective ] The paper was to study the growth-promoting and antagonistic action of endophytic bacteria strains Itb57 and Itb295 of tobacco to explore their functions in biological control. [ Method] The growth-promo...[ Objective ] The paper was to study the growth-promoting and antagonistic action of endophytic bacteria strains Itb57 and Itb295 of tobacco to explore their functions in biological control. [ Method] The growth-promoting effects of bacterial suspension ~ff endophytic bacteria Itb57 and Itb295 on tobacco seedling un- der different treatment modes were studied using potting method in greenhouse. The antagonistic action of bacterial suspension of endophytic bacteria Itb57 and Itb295 on Phytophthora nicotianae, Alternaria alternata and Botrytis cinerea were measured by duel culture method. [ Result] Bacterial suspensions of enduphytic bacteria Itb57 and Itb295 had certain growth-promoting effects on tobacco seedling, which could significantly increase the fresh weight and dry weight in aerial part; the growth-promoting effect of soaking ＋ spraying and irrigating treatment was the best. Itb57 strain had good antagonistic action against P. nicotianae. A. alterna- ta and B. cinerea, while Itb295 strain only had good antifungal effect against P. nicotianae. [ Conclusion] The results provided basis for the study and application of tobacco endophytic bacteria strains Itb57 and Itb295 in biocontrol of tobacco diseases.展开更多
[ Objective ] The paper was to isolate actinomycete strains with antagonistic activity against yam anthracnose from the rhizosphere soil of medicinal plants in Hainan Province, and identify its taxonomic status. [ Met...[ Objective ] The paper was to isolate actinomycete strains with antagonistic activity against yam anthracnose from the rhizosphere soil of medicinal plants in Hainan Province, and identify its taxonomic status. [ Method ] Using HV medium, actinomycete strains were isolated from the rhizesphere soil of frangipani （Plumeria rubra L. ）. The active antagonistic actinomycetes were selected by using confrontation culture method and antifimgal test of fermentation products. Ac- cording to morphology, combined with 16S rRNA gene analysis, the taxonomic status of active actinomycetes was identified. [ Result] Twelve strains of actinomyce- tes were isolated from the rhizosphere soil of medicinal plant frangipani. Strain 51173 showed significant antifungal activity against Colletotrichum gloeosporioides, which was identified to be a member of Streptomyces violaceusniger 16S rRNA gene clade. [ Conclusion] Strain 51173 showed a good application potential for bio- logical control against yam anthracnose.展开更多
The nonmonotonic dose-response curve(NMDRC)is a prevalent characteristic of endocrine-disrupting chemicals(EDCs)in activating nuclear receptors(NRs),implicating intricate regulatory mechanisms.In this study,the agonis...The nonmonotonic dose-response curve(NMDRC)is a prevalent characteristic of endocrine-disrupting chemicals(EDCs)in activating nuclear receptors(NRs),implicating intricate regulatory mechanisms.In this study,the agonistic and antagonistic activities of 11 bisphenols on the estrogen receptor(ER)were screened using MVLN cells.Three distinct dose-response patterns were observed,namely,S-shaped,inverted S-shaped,and bell-shaped profiles,corresponding to the agonistic,antagonistic,and nonmonotonic effects on ERs,respectively.To further explore NMDRC,bisphenol B(BPB)and bisphenol AF(BPAF),as representative compounds,were specifically investigated for their antagonistic effects on ER under high exposure concentrations(10-50μmol/L).Notably,the successive decline in cell viability suggested a subhealthy cell state upon high-dose chemical treatments,compromising cell response in ER transactivation.Unlike the specific effect induced by an ERαantagonist(4-hydroxytamoxifen,4OHT),the nonspecific inhibitory effects of BPB and BPAF on ER transactivation were further confirmed with their identical antagonistic curves,with or without E2 cotreatment,due to hydrophobicity-related cellular baseline toxicity.Accordingly,the inhibitory effects on NR transactivation might not necessarily be considered as a specific antagonistic activity.Thus,a more cautious inspection is highly encouraged in screening NR antagonism-centered endocrine-disrupting effects of emerging chemicals by carefully reviewing the specificity of signal reduction or inhibition.展开更多
In this study, plant growth-promoting rhizobacteria（PGPR） were evaluated as potential biocontrol agents against postharvest pathogens of apple fruits. In vitro bioassays revealed that, out of 30 isolates screened, i...In this study, plant growth-promoting rhizobacteria（PGPR） were evaluated as potential biocontrol agents against postharvest pathogens of apple fruits. In vitro bioassays revealed that, out of 30 isolates screened, isolates APEC136 and APEC170 had the most significant inhibitory effects against the mycelial growth of several fungal pathogens. Analysis of 16 S ribosomal RNA（rR NA） sequences identified the two effective isolates as Paenibacillus polymyxa and Bacillus subtilis, respectively. The two strains showed greater growth in brain-heart infusion broth than in other growth media. Treatment of harvested apples with suspensions of either strain reduced the symptoms of anthracnose disease caused by two fungal pathogens, Colletotrichum gloeosporioides and Colletotrichum acutatum, and white rot disease caused by Botryosphaeria dothidea. Increased productions of amylase and protease by APEC136, and increased productions of chitinase, amylase, and protease by APEC170 might have been responsible for inhibiting mycelial growth. The isolates caused a greater reduction in the growth of white rot than of anthracnose. These results indicate that the isolates APEC136 and APEC170 are promising agents for the biocontrol of anthracnose and white rot diseases in apples after harvest, and suggest that these isolates may be useful in controlling these diseases under field conditions.展开更多
One hundred twenty-five endophytic microorganisms were isolated from the roots,stems,and leaves of four prominent rice cultivars growing in temperate regions.Their potential to combat rice blast disease and promote pl...One hundred twenty-five endophytic microorganisms were isolated from the roots,stems,and leaves of four prominent rice cultivars growing in temperate regions.Their potential to combat rice blast disease and promote plant growth was investigated.The dual culture tests highlighted the strong antagonistic activity of five fungal(ranging from 89%–70%)and five bacterial(72%–61%)endophytes.Subsequent examination focused on volatile compounds produced by selected isolates to counter the blast pathogen.Among these,the highest chitinase(13.76μg mL−1)and siderophore(56.64%),was exhibited by Aspergillus flavus,and the highest HCN production was shown by Stenotrophomonas maltophilia(36.15μM mL−1).In terms of growth promotion traits,Aspergillus flavus and Enterobacter cloacae excelled in activities viz,phosphorous solubilization,ammonia production,auxin and gibberellic acid production,and nitrogen fixation.The Identity of these endophytes was confirmed through molecular analysis as Trichoderma afroharzianum,Trichoderma harzianum,Penicillium rubens,Aspergillus flavus,Stenotrophomonas rhizophila,Stenotrophomonas maltophilia,Bacillus cereus,Enterobacter cloacae,and Bacillus licheniformis.Under greenhouse conditions,the highest disease control was shown by isolate Bacillus licheniformis and A.flavus with an inhibition of 79%,followed by S.rhizophila(77%)and T.afroharzianum(73%).The overall results of this study showed that Bacillus licheniformis and Stenotrophomonas rhizophila have great potential to be used as bio-stimulant and biocontrol agents to manage rice blast disease.展开更多
Soil salinization affecting different crops is one of the serious threats to global food security.Soil salinity affects 20%and 33%of the total cultivated and irrigated agricultural lands,respectively,and has been repo...Soil salinization affecting different crops is one of the serious threats to global food security.Soil salinity affects 20%and 33%of the total cultivated and irrigated agricultural lands,respectively,and has been reported to caused a global crop production loss of 27.3 billion USD.The conventional approaches,such as using salt-tolerant varieties,saline soil scrapping,flushing,leaching,and adding supplements (e.g.,gypsum and lime),often fail to alleviate stress.In this context,developing diverse arrays of microbes enhancing crop productivity under saline soil conditions without harming soil health is necessary.Various advanced omics approaches have enabled gaining new insights into the structure and metabolic functions of plant-associated beneficial microbes.Various genera of salt-tolerating rhizobacteria ameliorating biotic and abiotic stresses have been isolated from different legumes,cereals,vegetables,and oil seeds under extreme alkaline and saline soil conditions.Rapid progress in rhizosphere microbiome research has revived the belief that plants may be more benefited from their association with interacting diverse microbial communities as compared with individual members in a community.In the last decade,several salt-tolerating plant growth-promoting rhizobacteria (PGPR) that improve crop production under salt stress have been exploited for the reclamation of saline agrosystems.This review highlights that the interaction of salt-tolerating microbes with plants improves crop productivity under salinity stress along with potential salt tolerance mechanisms involved and will open new avenues for capitalizing on cultivable diverse microbial communities to strengthen plant salt tolerance and,thus,to refine agricultural practices and production under saline conditions.展开更多
Series of novel derivatives of desloratadine designed as arginine vasopressin receptor antagonists were synthesized and structurally characterized by melting points,^1H NMR and HRMS.Their in vivo diuretic activities w...Series of novel derivatives of desloratadine designed as arginine vasopressin receptor antagonists were synthesized and structurally characterized by melting points,^1H NMR and HRMS.Their in vivo diuretic activities were evaluated on rats,and several target compounds showed promising diuretic results, especially compounds 8,18,27 and 31.Further in vitro bonding assay and cAMP assay showed that these compounds had a higher affinity to vasopressin V2 receptor than VI a receptor.Our studies indicated that desloratadine may be an active substructure for novel arginine vasopressin receptor antagonist development.展开更多
A series of novel phenothiazine derivatives was synthesized and tested for arginine vasopressin receptor antagonist activity. They were synthesized as novel arginine vasopressin receptor antagonists from phenothiazine...A series of novel phenothiazine derivatives was synthesized and tested for arginine vasopressin receptor antagonist activity. They were synthesized as novel arginine vasopressin receptor antagonists from phenothiazine as a scaffold via successive acylation, reduction and acylation reactions. Their structures were characterized by ^1H NMR, ^13C NMR and HRMS, and biological activity was evaluated by in vitro and in vivo studies. The in vitro binding assay indicated that several compounds are potent selective V2 receptor antagonists. Compounds with promising binding affinity to V2 receptors were selected to conduct the in vivo diuretic studies on Sprague-Dawley rats. Among them, 1n, 1r, It and 1v exhibited excellent diuretic activity, especially 1 r and 1v. Therefore, 1 r and 1v are potent novel AVP V2 receptor antagonist candidates.展开更多
The structure–activity relationship（SAR） study of a 1 2 3 4 4a 9a-hexahydro-1H-xanthene series of selective,human glucocorticoid receptor a（hGRa） antagonists is reported.Compounds were screened using hydroxyapati...The structure–activity relationship（SAR） study of a 1 2 3 4 4a 9a-hexahydro-1H-xanthene series of selective,human glucocorticoid receptor a（hGRa） antagonists is reported.Compounds were screened using hydroxyapatite-based GR binding and MMTV-Luc co-transfection reporter gene assays.Four different regions of the scaffold were modified to assess the effects on hGRa antagonism and related potency.Compound 8d exhibits an 8-fold better bioactivity than the original hit 1a,as well as an improved chemical stability,which make it a promising lead for the subsequent optimization.展开更多
Strain Z35,isolated from the rhizosphere of healthy Panax pseudoginseng under long-term continuous cropping,exhibits strong antagonistic activity against Fusarium oxysporum and shows potential as a biocontrol agent.Ho...Strain Z35,isolated from the rhizosphere of healthy Panax pseudoginseng under long-term continuous cropping,exhibits strong antagonistic activity against Fusarium oxysporum and shows potential as a biocontrol agent.However,the genetic and metabolic basis of its antimicrobial and plant growth-promoting functions remain unclear.In this study,plate confrontation assays confirmed that Z35 inhibited F.oxysporum by up to 75%.Whole-genome sequencing using the PacBio platform revealed a 38.65 Mb genome with seven contigs and one scaffold,a GC content of 47.48%,and 99.9%completeness(BUSCO).Phylogenetic analysis identified Z35 as Trichoderma koningiopsis.Genome annotation uncovered 49 secondary metabolite biosynthetic gene clusters and 717 functionally relevant genes,including clusters related to nonribosomal peptide synthetases(NRPS),polyketide synthases(PKS),and terpenes.These clusters are potentially responsible for producing bioactive compounds such as clavaric acid,the metachelin series,dimerumic acid,ascochlorin,and trichoxide.Non-targeted metabolomic profiling validated the presence of these metabolites in Z35 fermentation products,supporting their role in antifungal activity and plant-beneficial effects.This study provides insights into the genetic and metabolic mechanisms underlying Z35's biocontrol potential,offering a theoretical basis for its further development and application in sustainable agriculture.展开更多
Objective:To compare the phytochemical and antimicrobial activity of Ethiopian Kale leaves infusions,investigate the antioxidant activity and profile the major phytochemicals existing in the better solvent system.Meth...Objective:To compare the phytochemical and antimicrobial activity of Ethiopian Kale leaves infusions,investigate the antioxidant activity and profile the major phytochemicals existing in the better solvent system.Methods:Ethiopian Kale leaves were collected from Addis Ababa,Ethiopia,and extracted using different solvents.The qualitative phytochemical analysis,antibacterial assays,and Fourier Transform Infrared(FTIR) analysis are executed for all extracts.Antioxidant assay and Gas Chromatography-Mass Spectrometry(GC-MS) analysis are carried out for the solvent system,which showed better activity in preliminary studies.Results:The qualitative phytochemical analysis exposed the presence of different classes of phytoconstituents in most of the tested extracts.The broad spectrum of antibacterial activity(7-15 mm) was noted against the tested bacterial species.The functional groups of the extracts are reported by FTIR analysis.The antioxidant ability of ethanol extract was found to be(62.92±0.34)% for 2,2-diphenyl-1-picrylhydrazyl(DPPH*) assay and(71.12±0.41)% for 2,2-azinobis(3-ethylbenzothiazoline-6-sulfonic acid)(ABTS) assay.More than 17 major phytocompounds in ethanol extract were profiled by GC-MS analysis.Conclusion:The ethanol extract of Ethiopian Kale leaves contain a good source of phytochemicals and it can be a significant source for various functional applications.展开更多
Objective:To investigate the in vivo efficacy and immune-modulatory potential of antagonistic strain,Streptomyces sp.MAPS15 isolated from marine sponge in Penaeus monodon(P.monodon).Methods:In this study,culture of St...Objective:To investigate the in vivo efficacy and immune-modulatory potential of antagonistic strain,Streptomyces sp.MAPS15 isolated from marine sponge in Penaeus monodon(P.monodon).Methods:In this study,culture of Streptomyces sp.was incorporated into a commercial feed.P.monodon was orally administered with MAPS15 diet for a period of 21 days followed by a challenge experiment and survival rate was calculated.In addition,the effect of MAPS15 diet on immunological parameters of the haemolymph of P.monodon was also assessed.Results:The overall results of the study showed that survival performance was prominent in MAPS15 treated group when compared with un-treated control groups.That could pertain to the ability of MAPS15 to produce antibiotic compounds to suppress the growth of invading pathogens and thereby increase the disease resistance potency and survival rate.From the results of the immunological studies,it can be envisaged that the immune responses were generally more pronounced with MAPS15 diet treated group.Conclusions:Based on the overall findings,it could be inferred that the health of P.monodon is improved when they are fed with MAPS15 diet for a period of 21 days.展开更多
Emerging synthetic or derivative chemicals have drawn global concern due to their potential endocrine-disrupting effects,either as agonists or antagonists or through indirect effects on enzymes of signal transduction ...Emerging synthetic or derivative chemicals have drawn global concern due to their potential endocrine-disrupting effects,either as agonists or antagonists or through indirect effects on enzymes of signal transduction pathways.Currently,in vitro screening models are limited to poor tolerance,robustness,high cost and need for sphisticated equipment or complex procedures that require high levels of expertise.Herein,a multiplex analysis platform based on autobioluminescent yeast strains,including BLYhERaS,BLYhERbS,BLYhPRS,BLYhARS,BLYhMRS,and BLYhGRS,was developed for use in easy,rapid,robust,and sensitive screening for potential modulation of endocrine systems.Methods were applied to assess endocrine-disrupting effects of Bisphenol A(BPA)and its alternatives.Disrupting activities of bisphenols(BPs)varied greatly,and some BPA substitutes exerted more potent activities than those of BPA.Most BPs were primarily agonists of ERa and ERb,while others were antagonists to AR,PR,GR,and MR.BPP and BPM exhibited non-monotonic dose-response relationships toward ERa and ERb,and BHPF and BPG displayed converse disrupting activities to ERa and ERb.Overall,the bioassay system provides an efficient tool for comprehensive evaluation of endocrine-disrupting activities of emerging contaminants.展开更多
Background Bioactive proteins, such as cytokines and chemokines, have not been systematically evaluated in healthy and preeclamptic pregnancies. We aimed to investigate the difference of these proteins between healthy...Background Bioactive proteins, such as cytokines and chemokines, have not been systematically evaluated in healthy and preeclamptic pregnancies. We aimed to investigate the difference of these proteins between healthy and preeclamptic pregnancies in order to help clarify their potential roles in the pathogenesis of hypertension and proteinuria in preeclampsia. Methods Samples of amniotic fluid and maternal/umbilical cord blood were collected from normal pregnancies and women with preeclampsia for examination of bioactive proteins. Fifty-three pregnant women were enrolled in this study. Of them, 30 pregnant women were recruited as healthy controls, and 23 pregnant women were diagnosed with preeclampsia. An antibody array was used to screen for higher levels of cytokines and related proteins in amniotic fluid than in the blood samples, and these proteins were then selected for quantification by immunoassay. Results Interleukin-1 receptor 4, hepatocyte growth factor, and urokinase plasminogen activator receptor were significantly elevated in the blood of preec^ampsia patients. In particular, intedeukin-1 receptor 4 was 8-fold higher in preeclampsia patients than in the healthy pregnancies. Moreover, in cord blood samples hepatocyte growth factor and interleukin-8 were significantly higher in preeclampsia patients. Conclusions Because of the biologic activities, Interleukin-1 receptor 4, hepatocyte growth factor, urokinase plasminogen activator receptor and interleukin-8 in maternal and/or cord blood could play a role in the pathogenesis of hypertension and proteinuria in preeclampsia.展开更多
基金Supported by the Agro-scientific Research of China(201203009)the Ministry of Agriculture,China
文摘The antagonistic activity of Lactobacillus acidophilus KLDS1.0901, KLDS1.0902, KLDSI.1003 and NCFM against Escherichia coli O157 ： H7 were investigated in this study. The culture supematants of all the L. acidophilus stains showed high bacteriostatic activities against E. coli O 157 ： H7 and the bacteriostatic substances of their Cell-Free Supernatants （CFS） were preliminarily determined from organic acids. The bacteriostatic activity from CFS or viable L. acidophilus against E. coli O157 ： H7 was also assessed by using co-incubation methods, CFS had high bactericidal activity against E. coli O157 ： H7, no viable E. coli O157 ： H7 was detected when 5×10^7 CfU ofE. coli O157 ： H7 was added to 5 mL of CFS and incubated at 37℃ for 2 h. However, L. acidophilus themselves had no bacteriostatic activity after directly contacted with E. coli O157 ： H7. The inhibition E. coli O157 ： H7 adhesion and colonization of L. acidophilus were also investigated based on competition, exclusion and displacement assays. L. acidophilus KLDS1.0901, KLDSI.1003 and NCFM strains were effective to displace E. coli O157 ： H7 from a Caco-2 cell layer in competition and exclusion assays. However, in displacement assay, all of the strains showed no significant antagonistic activities. Meanwhile, the probiotic potential of L. acidophilus strains was investigated based on adhesion assay to Caco-2 cells and anti- inflammatory effects by IL-8 produced in Caco-2 cells. The adhesion ability and anti-inflammatory effects of L. acidophilus strains showed a strain-dependent manner. In general, L. acidophilus KLDS 1.0901 and NCFM showed better probiotic potential than KLDS1.0902 and KLDSI.1003. Thus, the use ofL. acidophilus KLDS1.0901 and NCFM to prevent or treat of diseases associated induced E. coli O157 ： H7 in vivo was suggested.
文摘Prediction of antagonistic activity of <em>β</em>-carboline and its thirteen derivatives has been made using topological descriptors viz, connectivity index, and kappa shape index of different orders. For evaluation of values of descriptor, molecular modeling and geometry optimization of all the compounds were carried out with CAChe Pro software by opting semiempirical PM3 method using MOPAC 2002. For prediction of activity multiple linear regression analysis (MLR) was performed. MLR analysis has been made by Project Leader Software associated with CAChe by using the above descriptors as independent variables and biological activity as dependent variables. We were performed leave-one-out methods and the result reflected a direct relationship between biological activity and connectivity index of zero order, while indirect relationship with connectivity index of second order and thus connectivity index is a reliable descriptor to predict the biological activity of <em>β</em>-carboline and its various derivatives.
基金supported by the Scientific Research Foundation of Xiamen Marine Research and Development Institute (No. K10102 (1))
文摘A strain LHB02 with strong antibacterial activity against some aquatic pathogens was screened from the coastal marine sediment in Fujian province, China. LHB02 was identified as Bacillus subtilis, based on its 16S rRNA sequence, together with the morphological, physiological and biochemical characteristics. The antagonistic activity of strain LHB02 and its optimal fermentation conditions were also investigated. The results showed that LHB02 had strong antagonistic activity against 3 species of vibrios： Vibrio harveyi,Vibrio alginolyticus and Vibrio anguillarum, and the optimum fermentation conditions for the strain LHB02 were as follows： KB culture medium （peptone 20 g, glycerol 10 mL, K2HPO4 1.5 g, MgSO 4 .7H2O 1.5 g, H2O 1 000 mL）; temperature, 28 ℃; pH ,7.0; culture time, 36 h; and inoculation amount, 1.5% （v/v）.
基金Supported by National Natural Science Foundation of China(30800040)Excellent Youth Science and Technology Fund of Anhui Province(10040606Y04)教育部留学回国人员科研启动基金资助项目~~
文摘[ Objective] The paper was to screen the antagonistic strain against Phytophthora sojae with biocontrol potential, and provide basis for searching control measures and designing new control strategies against P. sojae. [ Method] The rhizosphere soil of soybean was collected from three different places in Heilongjiang Province, and various soil microorganisms were isolated. Dual culture method was used to screen the microorganism with antagonistic effect against P. sojae. On this basis, the growth inhibition rate of the microorganism with stronger antagonistic effect against P. sojae was determined, and its control effect against P. sojae was also measured. [ Result] A strain of bacterium with relatively good antagonistic effect was isolated from soil, and named as strain B048. Dual test showed that the growth inhibition rate of antagonistic bacterium 11048 against P. sojac reached 97.5%. Antagonistic endurance tests showed that the width of inhibition zone was still 20.0 mm after dual culture with P. sojac for21 d. In potting experiment, the control effect of B048 against P. sojae was 100%. The antagonistic bacterium was primarily identified to be Bacillus pumilus through morphology and 16S rDNA sequence analysis. [Condusion] The antagonistic bacterium B048 had good prospect to be developed as the biocontrol bacterium against P. sojae.
基金Supported by Natural Science Foundation of Chongqing City(CSTC,2009BB1294)~~
文摘[ Objective ] The paper was to study the growth-promoting and antagonistic action of endophytic bacteria strains Itb57 and Itb295 of tobacco to explore their functions in biological control. [ Method] The growth-promoting effects of bacterial suspension ~ff endophytic bacteria Itb57 and Itb295 on tobacco seedling un- der different treatment modes were studied using potting method in greenhouse. The antagonistic action of bacterial suspension of endophytic bacteria Itb57 and Itb295 on Phytophthora nicotianae, Alternaria alternata and Botrytis cinerea were measured by duel culture method. [ Result] Bacterial suspensions of enduphytic bacteria Itb57 and Itb295 had certain growth-promoting effects on tobacco seedling, which could significantly increase the fresh weight and dry weight in aerial part; the growth-promoting effect of soaking ＋ spraying and irrigating treatment was the best. Itb57 strain had good antagonistic action against P. nicotianae. A. alterna- ta and B. cinerea, while Itb295 strain only had good antifungal effect against P. nicotianae. [ Conclusion] The results provided basis for the study and application of tobacco endophytic bacteria strains Itb57 and Itb295 in biocontrol of tobacco diseases.
基金Supported by Youth Fund Project of Hainan University ( qnjj1018)Key Discipline Grant of Crop Science of Hainan Province~~
文摘[ Objective ] The paper was to isolate actinomycete strains with antagonistic activity against yam anthracnose from the rhizosphere soil of medicinal plants in Hainan Province, and identify its taxonomic status. [ Method ] Using HV medium, actinomycete strains were isolated from the rhizesphere soil of frangipani （Plumeria rubra L. ）. The active antagonistic actinomycetes were selected by using confrontation culture method and antifimgal test of fermentation products. Ac- cording to morphology, combined with 16S rRNA gene analysis, the taxonomic status of active actinomycetes was identified. [ Result] Twelve strains of actinomyce- tes were isolated from the rhizosphere soil of medicinal plant frangipani. Strain 51173 showed significant antifungal activity against Colletotrichum gloeosporioides, which was identified to be a member of Streptomyces violaceusniger 16S rRNA gene clade. [ Conclusion] Strain 51173 showed a good application potential for bio- logical control against yam anthracnose.
基金supported by the National Key R&D Program of China(2024YFA0918800)Strategic Priority Research Program of the Chinese Academy of Sciences(XDB0750300)National Natural Science Foundation of China(22193051,22276212).
文摘The nonmonotonic dose-response curve(NMDRC)is a prevalent characteristic of endocrine-disrupting chemicals(EDCs)in activating nuclear receptors(NRs),implicating intricate regulatory mechanisms.In this study,the agonistic and antagonistic activities of 11 bisphenols on the estrogen receptor(ER)were screened using MVLN cells.Three distinct dose-response patterns were observed,namely,S-shaped,inverted S-shaped,and bell-shaped profiles,corresponding to the agonistic,antagonistic,and nonmonotonic effects on ERs,respectively.To further explore NMDRC,bisphenol B(BPB)and bisphenol AF(BPAF),as representative compounds,were specifically investigated for their antagonistic effects on ER under high exposure concentrations(10-50μmol/L).Notably,the successive decline in cell viability suggested a subhealthy cell state upon high-dose chemical treatments,compromising cell response in ER transactivation.Unlike the specific effect induced by an ERαantagonist(4-hydroxytamoxifen,4OHT),the nonspecific inhibitory effects of BPB and BPAF on ER transactivation were further confirmed with their identical antagonistic curves,with or without E2 cotreatment,due to hydrophobicity-related cellular baseline toxicity.Accordingly,the inhibitory effects on NR transactivation might not necessarily be considered as a specific antagonistic activity.Thus,a more cautious inspection is highly encouraged in screening NR antagonism-centered endocrine-disrupting effects of emerging chemicals by carefully reviewing the specificity of signal reduction or inhibition.
基金supported by the 2016 Research Fund of Andong National University,Gyeongbuk Province,Korea
文摘In this study, plant growth-promoting rhizobacteria（PGPR） were evaluated as potential biocontrol agents against postharvest pathogens of apple fruits. In vitro bioassays revealed that, out of 30 isolates screened, isolates APEC136 and APEC170 had the most significant inhibitory effects against the mycelial growth of several fungal pathogens. Analysis of 16 S ribosomal RNA（rR NA） sequences identified the two effective isolates as Paenibacillus polymyxa and Bacillus subtilis, respectively. The two strains showed greater growth in brain-heart infusion broth than in other growth media. Treatment of harvested apples with suspensions of either strain reduced the symptoms of anthracnose disease caused by two fungal pathogens, Colletotrichum gloeosporioides and Colletotrichum acutatum, and white rot disease caused by Botryosphaeria dothidea. Increased productions of amylase and protease by APEC136, and increased productions of chitinase, amylase, and protease by APEC170 might have been responsible for inhibiting mycelial growth. The isolates caused a greater reduction in the growth of white rot than of anthracnose. These results indicate that the isolates APEC136 and APEC170 are promising agents for the biocontrol of anthracnose and white rot diseases in apples after harvest, and suggest that these isolates may be useful in controlling these diseases under field conditions.
基金The authors extend their appreciation to the Researchers Supporting Project Number(RSP2023R298),King Saud University,Riyadh,Saudi Arabia.
文摘One hundred twenty-five endophytic microorganisms were isolated from the roots,stems,and leaves of four prominent rice cultivars growing in temperate regions.Their potential to combat rice blast disease and promote plant growth was investigated.The dual culture tests highlighted the strong antagonistic activity of five fungal(ranging from 89%–70%)and five bacterial(72%–61%)endophytes.Subsequent examination focused on volatile compounds produced by selected isolates to counter the blast pathogen.Among these,the highest chitinase(13.76μg mL−1)and siderophore(56.64%),was exhibited by Aspergillus flavus,and the highest HCN production was shown by Stenotrophomonas maltophilia(36.15μM mL−1).In terms of growth promotion traits,Aspergillus flavus and Enterobacter cloacae excelled in activities viz,phosphorous solubilization,ammonia production,auxin and gibberellic acid production,and nitrogen fixation.The Identity of these endophytes was confirmed through molecular analysis as Trichoderma afroharzianum,Trichoderma harzianum,Penicillium rubens,Aspergillus flavus,Stenotrophomonas rhizophila,Stenotrophomonas maltophilia,Bacillus cereus,Enterobacter cloacae,and Bacillus licheniformis.Under greenhouse conditions,the highest disease control was shown by isolate Bacillus licheniformis and A.flavus with an inhibition of 79%,followed by S.rhizophila(77%)and T.afroharzianum(73%).The overall results of this study showed that Bacillus licheniformis and Stenotrophomonas rhizophila have great potential to be used as bio-stimulant and biocontrol agents to manage rice blast disease.
文摘Soil salinization affecting different crops is one of the serious threats to global food security.Soil salinity affects 20%and 33%of the total cultivated and irrigated agricultural lands,respectively,and has been reported to caused a global crop production loss of 27.3 billion USD.The conventional approaches,such as using salt-tolerant varieties,saline soil scrapping,flushing,leaching,and adding supplements (e.g.,gypsum and lime),often fail to alleviate stress.In this context,developing diverse arrays of microbes enhancing crop productivity under saline soil conditions without harming soil health is necessary.Various advanced omics approaches have enabled gaining new insights into the structure and metabolic functions of plant-associated beneficial microbes.Various genera of salt-tolerating rhizobacteria ameliorating biotic and abiotic stresses have been isolated from different legumes,cereals,vegetables,and oil seeds under extreme alkaline and saline soil conditions.Rapid progress in rhizosphere microbiome research has revived the belief that plants may be more benefited from their association with interacting diverse microbial communities as compared with individual members in a community.In the last decade,several salt-tolerating plant growth-promoting rhizobacteria (PGPR) that improve crop production under salt stress have been exploited for the reclamation of saline agrosystems.This review highlights that the interaction of salt-tolerating microbes with plants improves crop productivity under salinity stress along with potential salt tolerance mechanisms involved and will open new avenues for capitalizing on cultivable diverse microbial communities to strengthen plant salt tolerance and,thus,to refine agricultural practices and production under saline conditions.
基金project was supported by National 973 Plan(Nos. 2010CB735602 and 2012CB724002)National Major Scientific and Technological Special Project for "Significant New Drugs Development"(No.2011ZX09401-009)
文摘Series of novel derivatives of desloratadine designed as arginine vasopressin receptor antagonists were synthesized and structurally characterized by melting points,^1H NMR and HRMS.Their in vivo diuretic activities were evaluated on rats,and several target compounds showed promising diuretic results, especially compounds 8,18,27 and 31.Further in vitro bonding assay and cAMP assay showed that these compounds had a higher affinity to vasopressin V2 receptor than VI a receptor.Our studies indicated that desloratadine may be an active substructure for novel arginine vasopressin receptor antagonist development.
基金supported by National Major Scientific and Technological Special Project for "Significant New Drugs Development"(Nos.2011ZX09401-009 and 2013ZX09102014)
文摘A series of novel phenothiazine derivatives was synthesized and tested for arginine vasopressin receptor antagonist activity. They were synthesized as novel arginine vasopressin receptor antagonists from phenothiazine as a scaffold via successive acylation, reduction and acylation reactions. Their structures were characterized by ^1H NMR, ^13C NMR and HRMS, and biological activity was evaluated by in vitro and in vivo studies. The in vitro binding assay indicated that several compounds are potent selective V2 receptor antagonists. Compounds with promising binding affinity to V2 receptors were selected to conduct the in vivo diuretic studies on Sprague-Dawley rats. Among them, 1n, 1r, It and 1v exhibited excellent diuretic activity, especially 1 r and 1v. Therefore, 1 r and 1v are potent novel AVP V2 receptor antagonist candidates.
基金supported in part by grants from the Ministry of Health of China (Nos. 2012ZX09304-011, 2013ZX09401003-005, 2013ZX09507001 and 2013ZX09507002)Shanghai Science and Technology Development Fund (No. 13DZ2290300)Thousand Talents Program in China
文摘The structure–activity relationship（SAR） study of a 1 2 3 4 4a 9a-hexahydro-1H-xanthene series of selective,human glucocorticoid receptor a（hGRa） antagonists is reported.Compounds were screened using hydroxyapatite-based GR binding and MMTV-Luc co-transfection reporter gene assays.Four different regions of the scaffold were modified to assess the effects on hGRa antagonism and related potency.Compound 8d exhibits an 8-fold better bioactivity than the original hit 1a,as well as an improved chemical stability,which make it a promising lead for the subsequent optimization.
基金supported by the National Key Research and Development(2021YFD1601003)the Project of The Sino-Vietnamese International Joint Laboratory for Characteristic&Cash Crops Green Development of Yunnan Province(202403AP140013)Development and Application of Personalized Cigarette Products'(2023CP02).
文摘Strain Z35,isolated from the rhizosphere of healthy Panax pseudoginseng under long-term continuous cropping,exhibits strong antagonistic activity against Fusarium oxysporum and shows potential as a biocontrol agent.However,the genetic and metabolic basis of its antimicrobial and plant growth-promoting functions remain unclear.In this study,plate confrontation assays confirmed that Z35 inhibited F.oxysporum by up to 75%.Whole-genome sequencing using the PacBio platform revealed a 38.65 Mb genome with seven contigs and one scaffold,a GC content of 47.48%,and 99.9%completeness(BUSCO).Phylogenetic analysis identified Z35 as Trichoderma koningiopsis.Genome annotation uncovered 49 secondary metabolite biosynthetic gene clusters and 717 functionally relevant genes,including clusters related to nonribosomal peptide synthetases(NRPS),polyketide synthases(PKS),and terpenes.These clusters are potentially responsible for producing bioactive compounds such as clavaric acid,the metachelin series,dimerumic acid,ascochlorin,and trichoxide.Non-targeted metabolomic profiling validated the presence of these metabolites in Z35 fermentation products,supporting their role in antifungal activity and plant-beneficial effects.This study provides insights into the genetic and metabolic mechanisms underlying Z35's biocontrol potential,offering a theoretical basis for its further development and application in sustainable agriculture.
基金Addis Ababa Science and Technology University, Ethiopia for providing partial financial support (Grant Reference No-AASTU-SSRF-CBCE-BT-2018)。
文摘Objective:To compare the phytochemical and antimicrobial activity of Ethiopian Kale leaves infusions,investigate the antioxidant activity and profile the major phytochemicals existing in the better solvent system.Methods:Ethiopian Kale leaves were collected from Addis Ababa,Ethiopia,and extracted using different solvents.The qualitative phytochemical analysis,antibacterial assays,and Fourier Transform Infrared(FTIR) analysis are executed for all extracts.Antioxidant assay and Gas Chromatography-Mass Spectrometry(GC-MS) analysis are carried out for the solvent system,which showed better activity in preliminary studies.Results:The qualitative phytochemical analysis exposed the presence of different classes of phytoconstituents in most of the tested extracts.The broad spectrum of antibacterial activity(7-15 mm) was noted against the tested bacterial species.The functional groups of the extracts are reported by FTIR analysis.The antioxidant ability of ethanol extract was found to be(62.92±0.34)% for 2,2-diphenyl-1-picrylhydrazyl(DPPH*) assay and(71.12±0.41)% for 2,2-azinobis(3-ethylbenzothiazoline-6-sulfonic acid)(ABTS) assay.More than 17 major phytocompounds in ethanol extract were profiled by GC-MS analysis.Conclusion:The ethanol extract of Ethiopian Kale leaves contain a good source of phytochemicals and it can be a significant source for various functional applications.
基金Supported by Department of Scientific and Industrial Research,New Delhi
文摘Objective:To investigate the in vivo efficacy and immune-modulatory potential of antagonistic strain,Streptomyces sp.MAPS15 isolated from marine sponge in Penaeus monodon(P.monodon).Methods:In this study,culture of Streptomyces sp.was incorporated into a commercial feed.P.monodon was orally administered with MAPS15 diet for a period of 21 days followed by a challenge experiment and survival rate was calculated.In addition,the effect of MAPS15 diet on immunological parameters of the haemolymph of P.monodon was also assessed.Results:The overall results of the study showed that survival performance was prominent in MAPS15 treated group when compared with un-treated control groups.That could pertain to the ability of MAPS15 to produce antibiotic compounds to suppress the growth of invading pathogens and thereby increase the disease resistance potency and survival rate.From the results of the immunological studies,it can be envisaged that the immune responses were generally more pronounced with MAPS15 diet treated group.Conclusions:Based on the overall findings,it could be inferred that the health of P.monodon is improved when they are fed with MAPS15 diet for a period of 21 days.
基金supported by the National Key Research and Development Program of China(NO.2023YFD1301505,No.2017YFC1600303)the Agricultural Science and Technology Innovation Program of CAAS(CAAS-ASTIP-IQSTAP-04)Prof.Giesy was supported by the Canada Research Chair program,the 2012"High Level Foreign Experts"(#GDT20143200016)program,funded by the State Administration of Foreign Experts Affairs,the P.R.China to Nanjing University and the Einstein Professor Program of the Chinese Academy of Sciences and a Distinguished Visiting Professorship in the Department of Environmental Sciences,Baylor University in Waco,TX,USA.
文摘Emerging synthetic or derivative chemicals have drawn global concern due to their potential endocrine-disrupting effects,either as agonists or antagonists or through indirect effects on enzymes of signal transduction pathways.Currently,in vitro screening models are limited to poor tolerance,robustness,high cost and need for sphisticated equipment or complex procedures that require high levels of expertise.Herein,a multiplex analysis platform based on autobioluminescent yeast strains,including BLYhERaS,BLYhERbS,BLYhPRS,BLYhARS,BLYhMRS,and BLYhGRS,was developed for use in easy,rapid,robust,and sensitive screening for potential modulation of endocrine systems.Methods were applied to assess endocrine-disrupting effects of Bisphenol A(BPA)and its alternatives.Disrupting activities of bisphenols(BPs)varied greatly,and some BPA substitutes exerted more potent activities than those of BPA.Most BPs were primarily agonists of ERa and ERb,while others were antagonists to AR,PR,GR,and MR.BPP and BPM exhibited non-monotonic dose-response relationships toward ERa and ERb,and BHPF and BPG displayed converse disrupting activities to ERa and ERb.Overall,the bioassay system provides an efficient tool for comprehensive evaluation of endocrine-disrupting activities of emerging contaminants.
基金This study was supported by grants from the National Natural Science Foundation of China，Science and Technology Bureau of Sichuan Province，Science and Technology Development of Chengdu City
文摘Background Bioactive proteins, such as cytokines and chemokines, have not been systematically evaluated in healthy and preeclamptic pregnancies. We aimed to investigate the difference of these proteins between healthy and preeclamptic pregnancies in order to help clarify their potential roles in the pathogenesis of hypertension and proteinuria in preeclampsia. Methods Samples of amniotic fluid and maternal/umbilical cord blood were collected from normal pregnancies and women with preeclampsia for examination of bioactive proteins. Fifty-three pregnant women were enrolled in this study. Of them, 30 pregnant women were recruited as healthy controls, and 23 pregnant women were diagnosed with preeclampsia. An antibody array was used to screen for higher levels of cytokines and related proteins in amniotic fluid than in the blood samples, and these proteins were then selected for quantification by immunoassay. Results Interleukin-1 receptor 4, hepatocyte growth factor, and urokinase plasminogen activator receptor were significantly elevated in the blood of preec^ampsia patients. In particular, intedeukin-1 receptor 4 was 8-fold higher in preeclampsia patients than in the healthy pregnancies. Moreover, in cord blood samples hepatocyte growth factor and interleukin-8 were significantly higher in preeclampsia patients. Conclusions Because of the biologic activities, Interleukin-1 receptor 4, hepatocyte growth factor, urokinase plasminogen activator receptor and interleukin-8 in maternal and/or cord blood could play a role in the pathogenesis of hypertension and proteinuria in preeclampsia.
