In order to save manpower and time costs,and to achieve simultaneous detection of multiple animal-derived components in meat and meat products,this study used multiple nucleotide polymorphism(MNP)marker technology bas...In order to save manpower and time costs,and to achieve simultaneous detection of multiple animal-derived components in meat and meat products,this study used multiple nucleotide polymorphism(MNP)marker technology based on the principle of high-throughput sequencing,and established a multi-locus 10 animalderived components identification method of cattle,goat,sheep,donkey,horse,chicken,duck,goose,pigeon,quail in meat and meat products.The specific loci of each species could be detected and the species could be accurately identified,including 5 loci for cattle and duck,3 loci for sheep,9 loci for chicken and horse,10 loci for goose and pigeon,6 loci for quail and 1 locus for donkey and goat,and an adulteration model was established to simulate commercially available samples.The results showed that the method established in this study had high throughput,good repeatability and accuracy,and was able to identify 10 animalderived components simultaneously with 100%repeatability accuracy.The detection limit was 0.1%(m/m)in simulated samples of chicken,duck and horse.Using the method established in this study to test commercially available samples,4 samples from 14 commercially available samples were detected to be inconsistent with the labels,of which 2 did not contain the target ingredient and 2 were adulterated with small amounts of other ingredients.展开更多
The internal microbial diversity and small molecular metabolites of Nuodeng ham in different processing years(the first,second and third year sample)were analyzed by high-throughput sequencing technology and gas chrom...The internal microbial diversity and small molecular metabolites of Nuodeng ham in different processing years(the first,second and third year sample)were analyzed by high-throughput sequencing technology and gas chromatography-time of flight mass spectrography(GC-TOF-MS)to study the effects of microorganisms and small molecular metabolites on the quality of ham in different processing years.The results showed that the dominant bacteria phyla of Nuodeng ham in different processing years were Proteobacteria and Firmicutes,the dominant fungi phyla were Ascomycota and Basidiomycota,while Staphylococcus and Aspergillus were the dominant bacteria and fungi of Nuodeng ham,respectively.Totally,252 kinds of small molecular metabolites were identified from Nuodeng ham in different processing years,and 12 different metabolites were screened through multivariate statistical analysis.Further metabolic pathway analysis showed that 23 metabolic pathways were related to ham fermentation,of which 8 metabolic pathways had significant effects on ham fermentation(Impact>0.01,P<0.05).The content of L-proline,phenyllactic acid,L-lysine,carnosine,taurine,D-proline,betaine and creatine were significantly positively correlated with the relative abundance of Staphylococcus and Serratia,but negatively correlated with the relative abundance of Halomonas,Aspergillus and Yamadazyma.展开更多
This study aimed to investigate the eff ect of LyPB on the intestinal microfl ora of giant pandas with indigestion,using high-throughput sequencing(HTS)technology.The species distribution and microfl oral density and ...This study aimed to investigate the eff ect of LyPB on the intestinal microfl ora of giant pandas with indigestion,using high-throughput sequencing(HTS)technology.The species distribution and microfl oral density and diversity before and after administration of the LyPB probiotic agent were analyzed.LyPB evidently has the ability to adjust the fl oral imbalance in the panda’s intestine.To test the eff ects of LyPB on the microfl ora of the panda gut,fecal samples were taken from a healthy giant panda(Anan)without administration of LyPB and from a dyspeptic giant panda Yangyang before and after LyPB administration.Compared with the sample obtained from healthy Anan(anan-c)and that obtained from dyspeptic Yangyang before LyPB administration(yangyang1),the sample taken from Yangyang(yangyang2)after LyPB administration displayed a signifi cant increase in the operational taxonomic unit index.An increase in the Chao index indicated an increase in the microfl oral richness,while an increase in the Shannon index indicated an increase in microfl oral diversity.At phylum and genus levels,a signifi cant increase was observed in the density of probiotic bacteria of phylum fi rmicutes,genus Streptococcus,while a drastic reduction in the density of Escherichia coli/Escherichia coli Shigella/bacteria of genus Shigella was observed.Data obtained in this study shows that LyPB preparations successfully improve the microbial structure within the panda’s intestinal canal by signifi cantly increasing the eff ective microbial community and decreasing the number of pathogenic microbes.展开更多
12%difenoconazole+fluxapyroxad SC(commercial name:Jiangong)was first released by BASF in China in 2016.It has been registered to control many diseases,including pear scab,apple Alternaria leaf spot,tomato early blight...12%difenoconazole+fluxapyroxad SC(commercial name:Jiangong)was first released by BASF in China in 2016.It has been registered to control many diseases,including pear scab,apple Alternaria leaf spot,tomato early blight,cucumber powdery mildew,etc.This study evaluated the bioactivity of Jiangong against Alternaria alternata and explored variations of phyllosphere microorganisms in both asymptomatic and tobacco brown spot leaves at different persistence periods(0,5,10,and 15 days post-fungicide application)using high-throughput sequencing technology.The results indicated that Jiangong effectively inhibited mycelial growth(average EC_(50) value of 0.51μg/mL),conidia germination(average EC_(50) value of 3.47μg/mL),and the carbon metabolism of A.alternata.Both asymptomatic and symptomatic leaves presented complex microbial communities.Higher fungal diversity was noted in asymptomatic leaves,while higher bacterial diversity was found in symptomatic leaves.After application,the diversity and abundance of microbial community structures in both types of leaves changed over time.Fungal microbiome communities showed greater sensitivity than bacterial groups,with the microbiome communities of asymptomatic leaves being more affected than those of symptomatic leaves.Fungal community diversity decreased for both symptomatic and asymptomatic leaves after 5 days of application,while the diversity of fungal community in symptomatic leaves showed an upward trend after 10 days of application.Meanwhile,bacterial community diversity increased in both symptomatic and asymptomatic leaves after 5 days of application but then declined in asymptomatic leaves after 15 days.The abundance of the dominant function group of phyllosphere bacteria(metabolism,genetic information processing,environmental information processing)was not affected by the application of Jiangong.However,the abundance of the dominant function group of phyllosphere fungi(animal pathogen-endophyte-wood saprotroph,endophyte-plant pathogen,plant pathogen-undefined saprotroph)was significantly affected by the application of Jiangong,and high variation was found in symptomatic leaves than that of asymptomatic leaves.The application of Jiangong-induced alterations in the community structure of the tobacco phyllosphere microbiome provides a basis for future tobacco brown spot control strategies based on phyllospheric microecology.展开更多
Commercial sterility does not guarantee the sustained stability of ultrahigh temperature(UHT)milk over 6 months shelf life.We explore the microbiota presented in normal(SZ)and quality deteriorated UHT milk(QY and WY)p...Commercial sterility does not guarantee the sustained stability of ultrahigh temperature(UHT)milk over 6 months shelf life.We explore the microbiota presented in normal(SZ)and quality deteriorated UHT milk(QY and WY)products from the same brand.Based on high-throughput sequencing research results,11 phyla and 54 genera were identified as dominant microbiota.Pseudomonas,Streptococcus,and Acinetobacter as core functional microbiota significantly influenced the UHT milk quality properties.Moreover,principal component analysis(PCA)and multivariate analyses were used to examine the quality characteristics,including 11 physicochemical parameters,10 fatty acids,and 2 enzyme activities,in normal and quality deteriorated UHT milk.We found that the abundance of Pseudomonas increased in quality deteriorated milk(WY)and showed a significant positive correlation with heat-resistant protease content.Acinetobacter in quality deteriorated milk(QY)also considerably contributed to the content of heat-resistant lipase,which resulted in spoilage deterioration of UHT milk.展开更多
Background:Soil aggregates are the basic units of soil structure,and their stability is a key indicator of soil quality and capacity to support ecosystem functions.The impacts of various environmental factors on soil ...Background:Soil aggregates are the basic units of soil structure,and their stability is a key indicator of soil quality and capacity to support ecosystem functions.The impacts of various environmental factors on soil aggregates have been widely studied.However,there remains elusive knowledge on the synergistic effects of changing forest stand structure on soil aggregate stability(SAS),particularly in subtropical China where soil erosion remains a critical issue.Methods:We investigated variations in the components of soil humus(HS),including humic acids(HAs),fulvic acids(FAs),and humins(HMs),under pure Chinese fir(Cunninghamia lanceolata)plantation(PP)and multilayered mixed plantation(MP)comprising C.lanceolata,Castanopsis hystrix,and Michelia hedyosperma.The state of soil aggregate stability,was determined by three separate methods,i.e.,dry-sieving,wet-sieving,and the Le Bissonnais.High-throughput sequencing was used to determine the diversity and composition of microbial communities under PP and MP.We then built partial least squares path models(PLS-PM)for assessing the responses of SAS to the variations in soil microorganisms and HS components.Results:The MP stands had significantly greater SAS(P<0.05),higher content of HAs and more rapid organic matter humification within aggregates,than the PP stands.High-throughput sequencing confirmed that the Pielou andα-diversity index values(Chao1 and Shannon)for fungi were all significantly higher under MP than under PP,while no marked difference was found in bacterialα-diversity between the two plantation types.Moreover,there were markedly greater abundance of three bacterial phyla(Verrucomicrobia,Chloroflexi,and Gemmatimonadetes)and three fungal phyla(Ascomycota,Kickxellomycota,and Glomeromycota),and significantly less abundance of two bacterial phyla(Planctomycetes and Firmicutes)and four fungal phyla(Basidiomycota,Mortierellomycota,Mucoromycota,and Rozellomycota)under MP than under PP.The Chloroflexi and Ascomycota phyla appeared to be the primary drivers of soil aggregate distribution.Our findings revealed that the promotion of SAS under MP was mainly driven by increased soil organic matter(SOM)content,which altered bacterial communities and enhanced fungal diversity,thereby increasing HAs content and the rate of organic matter humification.Conclusions:Considering the combined effects of enhanced soil quality,productivity,and relevant economic costs,introducing broadleaved tree species into Chinese fir plantations can be an effective strategy for stabilizing soil structure against erosion in subtropical China.Our study elucidated the controls on variations of SAS in Chinese fir-dominated plantations and demonstrated the benefit of converting pure Chinese fir plantation to multi-layered mixed plantations in increasing soil structural stability and improving site quality.展开更多
Fires are an important factor impacting forest ecosystems of Daxing'anling and have a significant effect on soil microbial community structure.In this study,highthroughput sequencing for 16 S rDNA and ITS rDNA wer...Fires are an important factor impacting forest ecosystems of Daxing'anling and have a significant effect on soil microbial community structure.In this study,highthroughput sequencing for 16 S rDNA and ITS rDNA were applied to analyze the changing characteristics and driving factors of bacterial and fungal community structures in burned areas with different fire severity.PICRUSt2 software was used to predict the functional characteristics of burned areas with different fire severity.The purpose was to unveil the responsive relationships among the structure and function of bacterial and fungal communities,fire severity,and post-disturbance restoration times.After high severity fires,the destruction of surface vegetation and loss of soil nutrients reduced the diversity and abundance of soil bacteria and fungi.The soil bacteria community structure,which was dominated by Acidobacteria,Proteobacteria,and Actinobacteria,changed to be dominated by Proteobacteria and Chloroflexi.As well,soil fungal community changed from domination by Helotiales,Eurotiales and Russulales to domination by Archaeorhizomycetales and Helotiales.Over time,soil bacterial community was gradually restored to prefire levels 30 years after the fire.Soil fungal community changed and failed to restore to pre-fire levels after 30 years.After low/intermediate severity fires,environmental factors were relatively unchanged so that soil bacteria diversity and abundance increased,optimizing community composition.The diversity and abundance of soil fungi decreased and the community structure changed slightly.Over time,both bacterial and fungal communities were gradually restored to pre-fire levels 30 years after the fire.After fire disturbance,with increasing severity,soil carbon fixation,lignin degradation,mineralization of organic nitrogen and hydrolysis of organic phosphorus are enhanced.Denitrification is weakened.Therefore,forest fires have certain positive effects on carbon,nitrogen and phosphorus cycles where soil bacteria and fungi are involved.展开更多
The objective of this study was to explore the effects of the inoculation of mixed starter cultures of Lactobacillus and Staphylococcus(labeled L-S)on microbial community and flavor in fermented sausages during the ri...The objective of this study was to explore the effects of the inoculation of mixed starter cultures of Lactobacillus and Staphylococcus(labeled L-S)on microbial community and flavor in fermented sausages during the ripening process.Culture-dependent(colony count)and culture-independent(high-throughput sequencing)methods were employed to evaluate bacterial communities.Volatile compounds were identified by gas chromatography-mass spectrometry,and the results were analyzed by principal component analysis(PCA).The identified bacteria with high relative abundance included Lactobacillus and Pediococcus,and the relative abundances of Leuconostoc and Weissella in fermented sausages were remarkably decreased at the end of the ripening process.At the end of ripening,2-nonenal,tetradecanal,ethylstearate and terpinyl acetate played substantial roles in the flavor development of the L-S fermented sausages.Sensory evaluation showed a high score in the L-S fermented sausages.Sausages can be inoculated with L-S starter culture to improve the safety and flavor of meat products.展开更多
Chilled duck meat is a popularly consumed meat in China but easily perishes at room/low temperature. Kojic acid is usually used as an antimicrobial. This study investigated the sensory scores, total bacteria number, a...Chilled duck meat is a popularly consumed meat in China but easily perishes at room/low temperature. Kojic acid is usually used as an antimicrobial. This study investigated the sensory scores, total bacteria number, and total volatile base nitrogen (TVB-N) value of chilled duck meat under kojic acid treatment during storage. The results presented that kojic acid suppressed the growth of spoilage bacteria and prolonged the shelf-life of chilled duck meat by at least two days. In further investigation, the bacterial community composition was explored through high-throughput sequencing. Pseudomonas spp. were the predominant spoilage bacteria after 6-day storage and were significantly suppressed by kojic acid. Besides, Brochothrix showed drug resistance and became the dominant bacteria in the kojic acid treated sample after 6-day storage. In conclusion, kojic acid maintained the sensorial, chemical, and microbial quality of duck meat stored at low temperatures. Meanwhile, kojic acid enriched the bacteria composition and showed strong antimicrobial activity against Pseudomonas spp.展开更多
Effects of a starter culture composed of Lactobacillus sakei,Pediococcus pentosaceus,Staphylococcus xylosus and S.carnosus at the ratios(m/m)of 1:1:1:1 on bacterial profile and biogenic amine accumulation in Chinese S...Effects of a starter culture composed of Lactobacillus sakei,Pediococcus pentosaceus,Staphylococcus xylosus and S.carnosus at the ratios(m/m)of 1:1:1:1 on bacterial profile and biogenic amine accumulation in Chinese Sichuan sausages were demonstrated.In starter culture-inoculated sausages,Lactobacillus spp.,Pediococcus spp.and Staphylococcus spp.were predominant bacterial genus and their relative abundances ranged from 70.14%to 25.98%,57.66%to 14.08%,and 15.71%to 13.40%during fermentation,respectively.Accordingly,Lactobacillus spp.and Weissella spp.were predominant bacterial genus and their relative abundances ranged from 63.14%to 24.70%and 49.40%to 11.96%during spontaneous fermentation,respectively.Furthermore,the abundances of undesirable microorganisms such as Yersinia spp.,Enterobacter spp.,Acietobacter spp.and Psychrobacter spp.were lower than that of the control.The levels of histamine,putrescine,tyramine and cadaverine in Chinese Sichuan sausages with starter cultures inoculation were significantly lower(P<0.05)than that of the control,and were decreased by 83.09%,69.38%,51.87%and 57.20%,respectively,at the end of the ripening.These results revealed that the starter cultures inoculation was a better alternative for microbial quality improvement and biogenic amine reduction of Chinese Sichuan sausages with good sensory attributes.展开更多
RNA-sequencing(RNA-seq),based on next-generation sequencing technologies,has rapidly become a standard and popular technology for transcriptome analysis.However,serious challenges still exist in analyzing and interpre...RNA-sequencing(RNA-seq),based on next-generation sequencing technologies,has rapidly become a standard and popular technology for transcriptome analysis.However,serious challenges still exist in analyzing and interpreting the RNA-seq data.With the development of high-throughput sequencing technology,the sequencing depth of RNA-seq data increases explosively.The intricate biological process of transcriptome is more complicated and diversified beyond our imagination.Moreover,most of the remaining organisms still have no available reference genome or have only incomplete genome annotations.Therefore,a large number of bioinformatics methods for various transcriptomics studies are proposed to effectively settle these challenges.This review comprehensively summarizes the various studies in RNA-seq data analysis and their corresponding analysis methods,including genome annotation,quality control and pre-processing of reads,read alignment,transcriptome assembly,gene and isoform expression quantification,differential expression analysis,data visualization and other analyses.展开更多
Sexual dimorphism of plants shapes the diff erent morphology and physiology between males and females.However,it is still unclear whether it infl uences belowground ecological processes.In this study,rhizosphere soil ...Sexual dimorphism of plants shapes the diff erent morphology and physiology between males and females.However,it is still unclear whether it infl uences belowground ecological processes.In this study,rhizosphere soil of male and female Populus deltoides and bulk soil were collected from an 18-year plantation(male and female trees mix-planted)and grouped into three soil compartments.Soil carbon(C),nitrogen(N)and phosphorus(P)levels were determined,and soil bacterial communities were analyzed by high-throughput sequencing.The results showed the less total carbon and total organic carbon,the more nutrients(available phosphorus,nitrate nitrogen and ammonium nitrogen)available in the rhizosphere soils of female poplars than soils of males.However,α-diversity indices of the rhizosphere bacterial communities under male plants were signifi-cantly higher.Principal component analysis showed that the bacterial communities were signifi cantly diff erent between the male and female soil compartments.Further,the bacterial co-occurrence network in soil under male trees had more nodes and edges than under females.BugBase analysis showed the more functional bacteria taxa related to biofi lm formation and antioxidation under males.The results indicate that soils under male poplars had more diverse and more complex co-occurrence networks of the rhizosphere bacterial community than soils under female trees,implying that male poplars might have better environmental adaptability.The study provides insight into the diff erent soil-microbe interactions of dioecious plants.More details about the infl uencing mechanism of sexual dimorphism on rhizosphere soil bacterial communities need to be further studied.展开更多
Pasteurized milk contains complex microbial communities affected by sterilization and storage conditions.This complex microflora may be the possible reason that pasteurized dairy products are highly prone to spoilage....Pasteurized milk contains complex microbial communities affected by sterilization and storage conditions.This complex microflora may be the possible reason that pasteurized dairy products are highly prone to spoilage.In this study,packaged pasteurized milk products collected from dairy processing factories in China were stored at 0,4,10,15,and 25℃ for 0−15 days and subjected to microbial identification using high-throughput sequencing.Accordingly,6 phyla and 44 genera were identified as the dominant microbiota.Moreover,the changes in nutritional composition of the pasteurized milk,including in 16 free amino acids,7 taste values,and 8 chemical constituents,were analyzed using principal component and multi-factor analyses.The Pearson correlation analysis identified Pseudomonas,Aeromonas,Paenibacillus,and Serratia genera as the core functional microbiota that significantly affects the nutritional composition of pasteurized milk.Hence,the results provide a comprehensive understanding of the safety and shelf-life of stored pasteurized milk.展开更多
基金financially supported by National Key R&D Program(2021YFF0701905)。
文摘In order to save manpower and time costs,and to achieve simultaneous detection of multiple animal-derived components in meat and meat products,this study used multiple nucleotide polymorphism(MNP)marker technology based on the principle of high-throughput sequencing,and established a multi-locus 10 animalderived components identification method of cattle,goat,sheep,donkey,horse,chicken,duck,goose,pigeon,quail in meat and meat products.The specific loci of each species could be detected and the species could be accurately identified,including 5 loci for cattle and duck,3 loci for sheep,9 loci for chicken and horse,10 loci for goose and pigeon,6 loci for quail and 1 locus for donkey and goat,and an adulteration model was established to simulate commercially available samples.The results showed that the method established in this study had high throughput,good repeatability and accuracy,and was able to identify 10 animalderived components simultaneously with 100%repeatability accuracy.The detection limit was 0.1%(m/m)in simulated samples of chicken,duck and horse.Using the method established in this study to test commercially available samples,4 samples from 14 commercially available samples were detected to be inconsistent with the labels,of which 2 did not contain the target ingredient and 2 were adulterated with small amounts of other ingredients.
基金supported by Major Science and Technology Projects of Yunnan Science and Technology Plan(2019ZG003)Yunnan Young and Middle-aged Academic and Technical Leader Reserve Talent Project(202105AC160068)。
文摘The internal microbial diversity and small molecular metabolites of Nuodeng ham in different processing years(the first,second and third year sample)were analyzed by high-throughput sequencing technology and gas chromatography-time of flight mass spectrography(GC-TOF-MS)to study the effects of microorganisms and small molecular metabolites on the quality of ham in different processing years.The results showed that the dominant bacteria phyla of Nuodeng ham in different processing years were Proteobacteria and Firmicutes,the dominant fungi phyla were Ascomycota and Basidiomycota,while Staphylococcus and Aspergillus were the dominant bacteria and fungi of Nuodeng ham,respectively.Totally,252 kinds of small molecular metabolites were identified from Nuodeng ham in different processing years,and 12 different metabolites were screened through multivariate statistical analysis.Further metabolic pathway analysis showed that 23 metabolic pathways were related to ham fermentation,of which 8 metabolic pathways had significant effects on ham fermentation(Impact>0.01,P<0.05).The content of L-proline,phenyllactic acid,L-lysine,carnosine,taurine,D-proline,betaine and creatine were significantly positively correlated with the relative abundance of Staphylococcus and Serratia,but negatively correlated with the relative abundance of Halomonas,Aspergillus and Yamadazyma.
文摘This study aimed to investigate the eff ect of LyPB on the intestinal microfl ora of giant pandas with indigestion,using high-throughput sequencing(HTS)technology.The species distribution and microfl oral density and diversity before and after administration of the LyPB probiotic agent were analyzed.LyPB evidently has the ability to adjust the fl oral imbalance in the panda’s intestine.To test the eff ects of LyPB on the microfl ora of the panda gut,fecal samples were taken from a healthy giant panda(Anan)without administration of LyPB and from a dyspeptic giant panda Yangyang before and after LyPB administration.Compared with the sample obtained from healthy Anan(anan-c)and that obtained from dyspeptic Yangyang before LyPB administration(yangyang1),the sample taken from Yangyang(yangyang2)after LyPB administration displayed a signifi cant increase in the operational taxonomic unit index.An increase in the Chao index indicated an increase in the microfl oral richness,while an increase in the Shannon index indicated an increase in microfl oral diversity.At phylum and genus levels,a signifi cant increase was observed in the density of probiotic bacteria of phylum fi rmicutes,genus Streptococcus,while a drastic reduction in the density of Escherichia coli/Escherichia coli Shigella/bacteria of genus Shigella was observed.Data obtained in this study shows that LyPB preparations successfully improve the microbial structure within the panda’s intestinal canal by signifi cantly increasing the eff ective microbial community and decreasing the number of pathogenic microbes.
基金Supported by China National Tobacco Corporation[No.110202101048(LS-08)]Hundred’Level Innovative Talent Foundation of Guizhou Province(No.GCC[2022]028-1,GCC[2023]108)+2 种基金Guizhou Science Technology Foundation(No.ZK[2021]Key036)the National Natural Science Foundation of China(No.32160522)Guizhou Province Applied Technology Research and Development Funding Post-subsidy Project and Guizhou Tobacco Company(No.2020XM03,2020XM22,2024XM06).
文摘12%difenoconazole+fluxapyroxad SC(commercial name:Jiangong)was first released by BASF in China in 2016.It has been registered to control many diseases,including pear scab,apple Alternaria leaf spot,tomato early blight,cucumber powdery mildew,etc.This study evaluated the bioactivity of Jiangong against Alternaria alternata and explored variations of phyllosphere microorganisms in both asymptomatic and tobacco brown spot leaves at different persistence periods(0,5,10,and 15 days post-fungicide application)using high-throughput sequencing technology.The results indicated that Jiangong effectively inhibited mycelial growth(average EC_(50) value of 0.51μg/mL),conidia germination(average EC_(50) value of 3.47μg/mL),and the carbon metabolism of A.alternata.Both asymptomatic and symptomatic leaves presented complex microbial communities.Higher fungal diversity was noted in asymptomatic leaves,while higher bacterial diversity was found in symptomatic leaves.After application,the diversity and abundance of microbial community structures in both types of leaves changed over time.Fungal microbiome communities showed greater sensitivity than bacterial groups,with the microbiome communities of asymptomatic leaves being more affected than those of symptomatic leaves.Fungal community diversity decreased for both symptomatic and asymptomatic leaves after 5 days of application,while the diversity of fungal community in symptomatic leaves showed an upward trend after 10 days of application.Meanwhile,bacterial community diversity increased in both symptomatic and asymptomatic leaves after 5 days of application but then declined in asymptomatic leaves after 15 days.The abundance of the dominant function group of phyllosphere bacteria(metabolism,genetic information processing,environmental information processing)was not affected by the application of Jiangong.However,the abundance of the dominant function group of phyllosphere fungi(animal pathogen-endophyte-wood saprotroph,endophyte-plant pathogen,plant pathogen-undefined saprotroph)was significantly affected by the application of Jiangong,and high variation was found in symptomatic leaves than that of asymptomatic leaves.The application of Jiangong-induced alterations in the community structure of the tobacco phyllosphere microbiome provides a basis for future tobacco brown spot control strategies based on phyllospheric microecology.
基金supported by the National Natural Science Foundation of China(32172279,31871831)Shenyang Science and Technology Innovation Platform Project(21-103-0-14,21-104-0-28)Shenyang City Youth Science and Technology Innovation Leading Talent Project(RC200495).
文摘Commercial sterility does not guarantee the sustained stability of ultrahigh temperature(UHT)milk over 6 months shelf life.We explore the microbiota presented in normal(SZ)and quality deteriorated UHT milk(QY and WY)products from the same brand.Based on high-throughput sequencing research results,11 phyla and 54 genera were identified as dominant microbiota.Pseudomonas,Streptococcus,and Acinetobacter as core functional microbiota significantly influenced the UHT milk quality properties.Moreover,principal component analysis(PCA)and multivariate analyses were used to examine the quality characteristics,including 11 physicochemical parameters,10 fatty acids,and 2 enzyme activities,in normal and quality deteriorated UHT milk.We found that the abundance of Pseudomonas increased in quality deteriorated milk(WY)and showed a significant positive correlation with heat-resistant protease content.Acinetobacter in quality deteriorated milk(QY)also considerably contributed to the content of heat-resistant lipase,which resulted in spoilage deterioration of UHT milk.
基金the National Natural Science Foundation of China(Nos.31960240 and 32171755)the Guangxi Natural Science Foundation(No.2019GXNSFAA185023)the Scientific Research Capacity Building Project for Youyiguan Forest Ecosystem Observation and Research Station of Guangxi under Grant No.2203513003。
文摘Background:Soil aggregates are the basic units of soil structure,and their stability is a key indicator of soil quality and capacity to support ecosystem functions.The impacts of various environmental factors on soil aggregates have been widely studied.However,there remains elusive knowledge on the synergistic effects of changing forest stand structure on soil aggregate stability(SAS),particularly in subtropical China where soil erosion remains a critical issue.Methods:We investigated variations in the components of soil humus(HS),including humic acids(HAs),fulvic acids(FAs),and humins(HMs),under pure Chinese fir(Cunninghamia lanceolata)plantation(PP)and multilayered mixed plantation(MP)comprising C.lanceolata,Castanopsis hystrix,and Michelia hedyosperma.The state of soil aggregate stability,was determined by three separate methods,i.e.,dry-sieving,wet-sieving,and the Le Bissonnais.High-throughput sequencing was used to determine the diversity and composition of microbial communities under PP and MP.We then built partial least squares path models(PLS-PM)for assessing the responses of SAS to the variations in soil microorganisms and HS components.Results:The MP stands had significantly greater SAS(P<0.05),higher content of HAs and more rapid organic matter humification within aggregates,than the PP stands.High-throughput sequencing confirmed that the Pielou andα-diversity index values(Chao1 and Shannon)for fungi were all significantly higher under MP than under PP,while no marked difference was found in bacterialα-diversity between the two plantation types.Moreover,there were markedly greater abundance of three bacterial phyla(Verrucomicrobia,Chloroflexi,and Gemmatimonadetes)and three fungal phyla(Ascomycota,Kickxellomycota,and Glomeromycota),and significantly less abundance of two bacterial phyla(Planctomycetes and Firmicutes)and four fungal phyla(Basidiomycota,Mortierellomycota,Mucoromycota,and Rozellomycota)under MP than under PP.The Chloroflexi and Ascomycota phyla appeared to be the primary drivers of soil aggregate distribution.Our findings revealed that the promotion of SAS under MP was mainly driven by increased soil organic matter(SOM)content,which altered bacterial communities and enhanced fungal diversity,thereby increasing HAs content and the rate of organic matter humification.Conclusions:Considering the combined effects of enhanced soil quality,productivity,and relevant economic costs,introducing broadleaved tree species into Chinese fir plantations can be an effective strategy for stabilizing soil structure against erosion in subtropical China.Our study elucidated the controls on variations of SAS in Chinese fir-dominated plantations and demonstrated the benefit of converting pure Chinese fir plantation to multi-layered mixed plantations in increasing soil structural stability and improving site quality.
基金funded by the National Key Research and Development Program of China (Grant No.2017 YFC0504003)Inner Mongolia Natural Science Foundation(No.2018MS03049)Young Teacher Research Fund Project of Forestry College of Inner Mongolia Agricultural University。
文摘Fires are an important factor impacting forest ecosystems of Daxing'anling and have a significant effect on soil microbial community structure.In this study,highthroughput sequencing for 16 S rDNA and ITS rDNA were applied to analyze the changing characteristics and driving factors of bacterial and fungal community structures in burned areas with different fire severity.PICRUSt2 software was used to predict the functional characteristics of burned areas with different fire severity.The purpose was to unveil the responsive relationships among the structure and function of bacterial and fungal communities,fire severity,and post-disturbance restoration times.After high severity fires,the destruction of surface vegetation and loss of soil nutrients reduced the diversity and abundance of soil bacteria and fungi.The soil bacteria community structure,which was dominated by Acidobacteria,Proteobacteria,and Actinobacteria,changed to be dominated by Proteobacteria and Chloroflexi.As well,soil fungal community changed from domination by Helotiales,Eurotiales and Russulales to domination by Archaeorhizomycetales and Helotiales.Over time,soil bacterial community was gradually restored to prefire levels 30 years after the fire.Soil fungal community changed and failed to restore to pre-fire levels after 30 years.After low/intermediate severity fires,environmental factors were relatively unchanged so that soil bacteria diversity and abundance increased,optimizing community composition.The diversity and abundance of soil fungi decreased and the community structure changed slightly.Over time,both bacterial and fungal communities were gradually restored to pre-fire levels 30 years after the fire.After fire disturbance,with increasing severity,soil carbon fixation,lignin degradation,mineralization of organic nitrogen and hydrolysis of organic phosphorus are enhanced.Denitrification is weakened.Therefore,forest fires have certain positive effects on carbon,nitrogen and phosphorus cycles where soil bacteria and fungi are involved.
基金supported by the Natural Science Research Projects of Shanxi Province (20210302123400) in ChinaAgricultural Valley Construction Research Project of Shanxi Province (SXNGJSKYZX201903)Key Science and Technology Programs in Agriculture of Shanxi Province (201903D211008)
文摘The objective of this study was to explore the effects of the inoculation of mixed starter cultures of Lactobacillus and Staphylococcus(labeled L-S)on microbial community and flavor in fermented sausages during the ripening process.Culture-dependent(colony count)and culture-independent(high-throughput sequencing)methods were employed to evaluate bacterial communities.Volatile compounds were identified by gas chromatography-mass spectrometry,and the results were analyzed by principal component analysis(PCA).The identified bacteria with high relative abundance included Lactobacillus and Pediococcus,and the relative abundances of Leuconostoc and Weissella in fermented sausages were remarkably decreased at the end of the ripening process.At the end of ripening,2-nonenal,tetradecanal,ethylstearate and terpinyl acetate played substantial roles in the flavor development of the L-S fermented sausages.Sensory evaluation showed a high score in the L-S fermented sausages.Sausages can be inoculated with L-S starter culture to improve the safety and flavor of meat products.
基金The Major Technological Innovation Projects of Hubei Province(2017ABA136).
文摘Chilled duck meat is a popularly consumed meat in China but easily perishes at room/low temperature. Kojic acid is usually used as an antimicrobial. This study investigated the sensory scores, total bacteria number, and total volatile base nitrogen (TVB-N) value of chilled duck meat under kojic acid treatment during storage. The results presented that kojic acid suppressed the growth of spoilage bacteria and prolonged the shelf-life of chilled duck meat by at least two days. In further investigation, the bacterial community composition was explored through high-throughput sequencing. Pseudomonas spp. were the predominant spoilage bacteria after 6-day storage and were significantly suppressed by kojic acid. Besides, Brochothrix showed drug resistance and became the dominant bacteria in the kojic acid treated sample after 6-day storage. In conclusion, kojic acid maintained the sensorial, chemical, and microbial quality of duck meat stored at low temperatures. Meanwhile, kojic acid enriched the bacteria composition and showed strong antimicrobial activity against Pseudomonas spp.
基金supported by National Natural Science Foundation of China(31772093)Key innovation projects of Chengdu Science and Technology(2019-YF05-00066-SN)Key Laboratory of Collaborative Control and Remediation of Soil and Water Pollution(GHBK-003)。
文摘Effects of a starter culture composed of Lactobacillus sakei,Pediococcus pentosaceus,Staphylococcus xylosus and S.carnosus at the ratios(m/m)of 1:1:1:1 on bacterial profile and biogenic amine accumulation in Chinese Sichuan sausages were demonstrated.In starter culture-inoculated sausages,Lactobacillus spp.,Pediococcus spp.and Staphylococcus spp.were predominant bacterial genus and their relative abundances ranged from 70.14%to 25.98%,57.66%to 14.08%,and 15.71%to 13.40%during fermentation,respectively.Accordingly,Lactobacillus spp.and Weissella spp.were predominant bacterial genus and their relative abundances ranged from 63.14%to 24.70%and 49.40%to 11.96%during spontaneous fermentation,respectively.Furthermore,the abundances of undesirable microorganisms such as Yersinia spp.,Enterobacter spp.,Acietobacter spp.and Psychrobacter spp.were lower than that of the control.The levels of histamine,putrescine,tyramine and cadaverine in Chinese Sichuan sausages with starter cultures inoculation were significantly lower(P<0.05)than that of the control,and were decreased by 83.09%,69.38%,51.87%and 57.20%,respectively,at the end of the ripening.These results revealed that the starter cultures inoculation was a better alternative for microbial quality improvement and biogenic amine reduction of Chinese Sichuan sausages with good sensory attributes.
文摘RNA-sequencing(RNA-seq),based on next-generation sequencing technologies,has rapidly become a standard and popular technology for transcriptome analysis.However,serious challenges still exist in analyzing and interpreting the RNA-seq data.With the development of high-throughput sequencing technology,the sequencing depth of RNA-seq data increases explosively.The intricate biological process of transcriptome is more complicated and diversified beyond our imagination.Moreover,most of the remaining organisms still have no available reference genome or have only incomplete genome annotations.Therefore,a large number of bioinformatics methods for various transcriptomics studies are proposed to effectively settle these challenges.This review comprehensively summarizes the various studies in RNA-seq data analysis and their corresponding analysis methods,including genome annotation,quality control and pre-processing of reads,read alignment,transcriptome assembly,gene and isoform expression quantification,differential expression analysis,data visualization and other analyses.
基金supported by the National Natural Science Foundation of China(32071751)the National key research and development program(2021YFD220120102)+1 种基金the Natural Science Foundation of Shandong Province(ZR2018ZC08N3)the funds of the Shandong Double Tops Program(Grant No.SYL2017XTTD03).
文摘Sexual dimorphism of plants shapes the diff erent morphology and physiology between males and females.However,it is still unclear whether it infl uences belowground ecological processes.In this study,rhizosphere soil of male and female Populus deltoides and bulk soil were collected from an 18-year plantation(male and female trees mix-planted)and grouped into three soil compartments.Soil carbon(C),nitrogen(N)and phosphorus(P)levels were determined,and soil bacterial communities were analyzed by high-throughput sequencing.The results showed the less total carbon and total organic carbon,the more nutrients(available phosphorus,nitrate nitrogen and ammonium nitrogen)available in the rhizosphere soils of female poplars than soils of males.However,α-diversity indices of the rhizosphere bacterial communities under male plants were signifi-cantly higher.Principal component analysis showed that the bacterial communities were signifi cantly diff erent between the male and female soil compartments.Further,the bacterial co-occurrence network in soil under male trees had more nodes and edges than under females.BugBase analysis showed the more functional bacteria taxa related to biofi lm formation and antioxidation under males.The results indicate that soils under male poplars had more diverse and more complex co-occurrence networks of the rhizosphere bacterial community than soils under female trees,implying that male poplars might have better environmental adaptability.The study provides insight into the diff erent soil-microbe interactions of dioecious plants.More details about the infl uencing mechanism of sexual dimorphism on rhizosphere soil bacterial communities need to be further studied.
基金supported by the National Natural Science Foundation of China(31871831,32172279)Liaoning Provincial Natural Science Foundation regional Joint Fund project(2020-MZLH-34)+1 种基金Shenyang City Youth Science and Technology Innovation Leading Talent Project(RC200495)Shenyang Science and technology innovation platform project(21-103-0-14,21-104-0-28).
文摘Pasteurized milk contains complex microbial communities affected by sterilization and storage conditions.This complex microflora may be the possible reason that pasteurized dairy products are highly prone to spoilage.In this study,packaged pasteurized milk products collected from dairy processing factories in China were stored at 0,4,10,15,and 25℃ for 0−15 days and subjected to microbial identification using high-throughput sequencing.Accordingly,6 phyla and 44 genera were identified as the dominant microbiota.Moreover,the changes in nutritional composition of the pasteurized milk,including in 16 free amino acids,7 taste values,and 8 chemical constituents,were analyzed using principal component and multi-factor analyses.The Pearson correlation analysis identified Pseudomonas,Aeromonas,Paenibacillus,and Serratia genera as the core functional microbiota that significantly affects the nutritional composition of pasteurized milk.Hence,the results provide a comprehensive understanding of the safety and shelf-life of stored pasteurized milk.
