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De Filippis F, Bonelli M, Bruno D, Sequino G, Montali A, Reguzzoni M, Pasolli E, Savy D, Cangemi S, Cozzolino V, Tettamanti G, Ercolini D, Casartelli M, Caccia S. Plastics shape the black soldier fly larvae gut microbiome and select for biodegrading functions. MICROBIOME 2023; 11:205. [PMID: 37705113 PMCID: PMC10500907 DOI: 10.1186/s40168-023-01649-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/26/2022] [Accepted: 07/16/2023] [Indexed: 09/15/2023]
Abstract
BACKGROUND In the last few years, considerable attention has been focused on the plastic-degrading capability of insects and their gut microbiota in order to develop novel, effective, and green strategies for plastic waste management. Although many analyses based on 16S rRNA gene sequencing are available, an in-depth analysis of the insect gut microbiome to identify genes with plastic-degrading potential is still lacking. RESULTS In the present work, we aim to fill this gap using Black Soldier Fly (BSF) as insect model. BSF larvae have proven capability to efficiently bioconvert a wide variety of organic wastes but, surprisingly, have never been considered for plastic degradation. BSF larvae were reared on two widely used plastic polymers and shotgun metagenomics was exploited to evaluate if and how plastic-containing diets affect composition and functions of the gut microbial community. The high-definition picture of the BSF gut microbiome gave access for the first time to the genomes of culturable and unculturable microorganisms in the gut of insects reared on plastics and revealed that (i) plastics significantly shaped bacterial composition at species and strain level, and (ii) functions that trigger the degradation of the polymer chains, i.e., DyP-type peroxidases, multicopper oxidases, and alkane monooxygenases, were highly enriched in the metagenomes upon exposure to plastics, consistently with the evidences obtained by scanning electron microscopy and 1H nuclear magnetic resonance analyses on plastics. CONCLUSIONS In addition to highlighting that the astonishing plasticity of the microbiota composition of BSF larvae is associated with functional shifts in the insect microbiome, the present work sets the stage for exploiting BSF larvae as "bioincubators" to isolate microbial strains and enzymes for the development of innovative plastic biodegradation strategies. However, most importantly, the larvae constitute a source of enzymes to be evolved and valorized by pioneering synthetic biology approaches. Video Abstract.
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Affiliation(s)
- Francesca De Filippis
- Department of Agricultural Sciences, University of Naples Federico II, Portici, Italy
- Task Force on Microbiome Studies, University of Naples Federico II, Naples, Italy
| | - Marco Bonelli
- Department of Biosciences, University of Milan, Milan, Italy
| | - Daniele Bruno
- Department of Biotechnology and Life Sciences, University of Insubria, Varese, Italy
| | - Giuseppina Sequino
- Department of Agricultural Sciences, University of Naples Federico II, Portici, Italy
| | - Aurora Montali
- Department of Biotechnology and Life Sciences, University of Insubria, Varese, Italy
| | - Marcella Reguzzoni
- Department of Medicine and Surgery, University of Insubria, Varese, Italy
| | - Edoardo Pasolli
- Department of Agricultural Sciences, University of Naples Federico II, Portici, Italy
- Task Force on Microbiome Studies, University of Naples Federico II, Naples, Italy
| | - Davide Savy
- Interdepartmental Research Centre of Nuclear Magnetic Resonance for the Environment, Agri-Food and New Materials (CERMANU), University of Naples Federico II, Portici, Italy
| | - Silvana Cangemi
- Interdepartmental Research Centre of Nuclear Magnetic Resonance for the Environment, Agri-Food and New Materials (CERMANU), University of Naples Federico II, Portici, Italy
| | - Vincenza Cozzolino
- Department of Agricultural Sciences, University of Naples Federico II, Portici, Italy
- Interdepartmental Research Centre of Nuclear Magnetic Resonance for the Environment, Agri-Food and New Materials (CERMANU), University of Naples Federico II, Portici, Italy
| | - Gianluca Tettamanti
- Department of Biotechnology and Life Sciences, University of Insubria, Varese, Italy
- Interuniversity Center for Studies on Bioinspired Agro-Environmental Technology (BAT Center), University of Naples Federico II, Portici, Italy
| | - Danilo Ercolini
- Department of Agricultural Sciences, University of Naples Federico II, Portici, Italy.
- Task Force on Microbiome Studies, University of Naples Federico II, Naples, Italy.
| | - Morena Casartelli
- Department of Biosciences, University of Milan, Milan, Italy.
- Interuniversity Center for Studies on Bioinspired Agro-Environmental Technology (BAT Center), University of Naples Federico II, Portici, Italy.
| | - Silvia Caccia
- Task Force on Microbiome Studies, University of Naples Federico II, Naples, Italy.
- Department of Biosciences, University of Milan, Milan, Italy.
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Zhang S, Zhong B, An X, Han Y, Xiao X, Zhang Q. Effect of moisture content on the evolution of bacterial communities and organic matter degradation during bioaugmented biogas residues composting. World J Microbiol Biotechnol 2022; 39:1. [PMID: 36344669 DOI: 10.1007/s11274-022-03454-7] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2022] [Accepted: 11/01/2022] [Indexed: 11/09/2022]
Abstract
Composting is an excellent way to recycle biogas residues into a stable, non-toxic agricultural end product. In this study, the dynamic changes of physical-chemical parameters and bacterial community in three groups of bioaugmentation composting systems at different moisture contents (MC) of 50% (MC50), 60% (MC60) and 70% (MC70) were monitored. The differences of bacterial communities in composts with different initial MC were compared, and the interaction between biological and non-biological parameters was also explored. The results revealed that after 30 days of composting, the biogas residues compost in MC60 reached highest temperature of 64 °C, total Kjeldahl nitrogen (TKN) of 2%, seed germination index (GI) of 110%, and the longest thermophilic period duration of 5 days (55 °C). Additionally, the result of high-throughput sequencing showed that the diversity of bacterial communities in MC60 was the highest, and the abundance of Actinobacteria (16.93-52.63%), Firmicutes (8.71-56.75%), and Proteobacteria (16.88-46.95%) in all groups were the highest at phylum level. The LEfSe analysis indicated that the abundance of Ochrobactrum and Cellulomonadaceae in MC60 was significantly (p < 0.05) higher than with other treatments. Moreover, canonical correspondence analysis (CCA) indicated thermophilic period duration is significantly (p < 0.05) positively correlated with Paenibacillus. Besides, it was found the relative abundance of Nocardiopsis and Georgenia has a significant (p < 0.01) correlation with the fertilizer efficiency of compost. These results showed that controlling the initial moisture content at 60% can improve the maturity and fertilizer efficiency of compost, and enable the bacteria beneficial to composting to gain the advantage of proliferation.
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Affiliation(s)
- Shulin Zhang
- College of Bioscience and Bioengineering, Jiangxi Engineering Laboratory for the Development and Utilization of Agricultural Microbial Resources, Jiangxi Agricultural University, Nanchang, 330045, People's Republic of China
| | - Bin Zhong
- College of Bioscience and Bioengineering, Jiangxi Engineering Laboratory for the Development and Utilization of Agricultural Microbial Resources, Jiangxi Agricultural University, Nanchang, 330045, People's Republic of China
| | - Xuejiao An
- College of Bioscience and Bioengineering, Jiangxi Engineering Laboratory for the Development and Utilization of Agricultural Microbial Resources, Jiangxi Agricultural University, Nanchang, 330045, People's Republic of China
| | - Yanyan Han
- College of Bioscience and Bioengineering, Jiangxi Engineering Laboratory for the Development and Utilization of Agricultural Microbial Resources, Jiangxi Agricultural University, Nanchang, 330045, People's Republic of China
| | - Xiaoshuang Xiao
- College of Bioscience and Bioengineering, Jiangxi Engineering Laboratory for the Development and Utilization of Agricultural Microbial Resources, Jiangxi Agricultural University, Nanchang, 330045, People's Republic of China
| | - Qinghua Zhang
- College of Bioscience and Bioengineering, Jiangxi Engineering Laboratory for the Development and Utilization of Agricultural Microbial Resources, Jiangxi Agricultural University, Nanchang, 330045, People's Republic of China.
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Wang X, Tian L, Li Y, Zhong C, Tian C. Effects of exogenous cellulose-degrading bacteria on humus formation and bacterial community stability during composting. BIORESOURCE TECHNOLOGY 2022; 359:127458. [PMID: 35700902 DOI: 10.1016/j.biortech.2022.127458] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/14/2022] [Revised: 06/04/2022] [Accepted: 06/09/2022] [Indexed: 06/15/2023]
Abstract
This study aimed to reveal the potential mechanism of influence exogenous cellulose-degrading bacteria (ECDB) exerted on humus synthesis during the co-composting of corn straw and cattle manure. By measuring the changes in physicochemical factors and bacterial communities, it was revealed that inoculation with ECDB enhanced the driving force of cellulose degradation and humus synthesis. ECDB not only directly participated in cellulose degradation as degrading bacteria, but also changed the bacterial community succession, and increased the abundance of bacterial communities associated with cellulose degradation. The results showed that ECDB stimulated the potential functions and interactions of bacterial communities. Structural equation modeling confirmed that ECDB acted mainly as a bioactivator to promote humus formation in co-composting of corn straw and cattle manure. Taken together, these findings offered new strategies which can be effectively utilized to increase the efficiency and quality of corn straw composting.
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Affiliation(s)
- Xinguang Wang
- Key Laboratory of Mollisols Agroecology, Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Changchun 130102, Jilin, China; College of Biotechnology, Tianjin University of Science and Technology, Tianjin 300457, China
| | - Lei Tian
- Key Laboratory of Mollisols Agroecology, Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Changchun 130102, Jilin, China
| | - Yingxin Li
- Key Laboratory of Mollisols Agroecology, Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Changchun 130102, Jilin, China
| | - Cheng Zhong
- College of Biotechnology, Tianjin University of Science and Technology, Tianjin 300457, China
| | - Chunjie Tian
- Key Laboratory of Mollisols Agroecology, Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Changchun 130102, Jilin, China.
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Zhu M, Zheng J, Xie J, Zhao D, Qiao ZW, Huang D, Luo HB. Effects of environmental factors on the microbial community changes during medium-high temperature Daqu manufacturing. Food Res Int 2022; 153:110955. [DOI: 10.1016/j.foodres.2022.110955] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2021] [Revised: 12/25/2021] [Accepted: 01/19/2022] [Indexed: 11/28/2022]
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Jiang Z, Li X, Li M, Zhu Q, Li G, Ma C, Li Q, Meng J, Liu Y, Li Q. Impacts of red mud on lignin depolymerization and humic substance formation mediated by laccase-producing bacterial community during composting. JOURNAL OF HAZARDOUS MATERIALS 2021; 410:124557. [PMID: 33234392 DOI: 10.1016/j.jhazmat.2020.124557] [Citation(s) in RCA: 53] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/01/2020] [Revised: 11/09/2020] [Accepted: 11/10/2020] [Indexed: 06/11/2023]
Abstract
The aim of this study was to investigate the impacts of red mud on lignin degradation, humic substance formation and laccase-producing bacterial community in composting to better improve composting performances. The results indicated that the organic matter contents of final compost products in the treatment group with red mud (T) decreased by 25.74%, which was more than the control group without red mud (CK) (12.09%). The final lignin degradation ratio and humic substance concentration of the T were 18.67% and 22.80% higher than that of the CK, respectively. The final C/N values of compost in the CK and T were 11.32 and 10.66, respectively, which were both less than 15, suggesting that compost reached maturity. Redundancy analysis showed that temperature was the main factors driving the variation of laccase-producing bacterial community. Pearson analysis suggested that Pseudomonas, Phenylobacterium, and Caulobacter were the most significantly correlated with lignin degradation and humification in the T.
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Affiliation(s)
- Zhiwei Jiang
- School of Chemistry and Chemical Engineering, Guangxi University, Nanning 530004, China
| | - Xintian Li
- School of Chemistry and Chemical Engineering, Guangxi University, Nanning 530004, China
| | - Mingqi Li
- School of Chemistry and Chemical Engineering, Guangxi University, Nanning 530004, China
| | - Qiuhui Zhu
- School of Chemistry and Chemical Engineering, Guangxi University, Nanning 530004, China
| | - Gen Li
- School of Chemistry and Chemical Engineering, Guangxi University, Nanning 530004, China
| | - Chaofan Ma
- School of Chemistry and Chemical Engineering, Guangxi University, Nanning 530004, China
| | - Qingyun Li
- School of Chemistry and Chemical Engineering, Guangxi University, Nanning 530004, China; Key Laboratory of Guangxi Biorefinery, Guangxi University, Nanning 530004, China
| | - Jianzong Meng
- College of Life Science and Technology, Guangxi University, Nanning 530004, China
| | - Youyan Liu
- School of Chemistry and Chemical Engineering, Guangxi University, Nanning 530004, China; Key Laboratory of Guangxi Biorefinery, Guangxi University, Nanning 530004, China
| | - Qunliang Li
- School of Chemistry and Chemical Engineering, Guangxi University, Nanning 530004, China; Key Laboratory of Guangxi Biorefinery, Guangxi University, Nanning 530004, China.
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Wang Y, Zhao C, Zhang D, Zhao M, Peng M, Guo P, Cui Z. Microbial Degradation of Zearalenone by a Novel Microbial Consortium, NZDC-6, and Its Application on Contaminated Corncob by Semisolid Fermentation. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2020; 68:1634-1644. [PMID: 31961687 DOI: 10.1021/acs.jafc.9b05343] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
A novel microbial consortium (NZDC-6) was screened and characterized to detoxify the estrogenic mycotoxin zearalenone (ZEA), which commonly contaminates maize and is a major threat to food and health security. We found NZDC-6 to be thermophilic and highly effective, with a 90.3% ZEA degradation ratio at an optimum temperature of 60 °C. NZDC-6 was also effective at degrading the more estrogenic ZEA cognates, α-zearalenol (α-ZAL) and β-zearalenol (β-ZAL), with >90% degradation ratios. To evaluate a practical application, ZEA-contaminated corncobs were treated with NZDC-6 via semisolid fermentation. Measurements of physicochemical parameters and 16S microbial diversity and redundancy analysis (RDA) indicated that ZEA removal was most efficient at a low corncob solid content (< 5%), as a high solid content overwhelmed the microbial metabolic load, leading to increased dissolved oxygen and lowered pH. Our results demonstrate that the control of environmental variables is crucial for effective ZEA microbial removal in practical applications.
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Affiliation(s)
- Yi Wang
- Institute of Agricultural Products Processing and Nuclear Agriculture Technology Research , Hubei Academy of Agricultural Sciences , Wuhan 430064 , China
| | - Chunxia Zhao
- Institute of Agricultural Products Processing and Nuclear Agriculture Technology Research , Hubei Academy of Agricultural Sciences , Wuhan 430064 , China
| | - Dongdong Zhang
- Institute of Marine Biology, Ocean College , Zhejiang University , Zhoushan , Zhejiang 316021, China
| | - Mingming Zhao
- Institute of Agricultural Products Processing and Nuclear Agriculture Technology Research , Hubei Academy of Agricultural Sciences , Wuhan 430064 , China
| | - Maomin Peng
- Institute of Agricultural Products Processing and Nuclear Agriculture Technology Research , Hubei Academy of Agricultural Sciences , Wuhan 430064 , China
| | - Peng Guo
- Institute of Agricultural Products Processing and Nuclear Agriculture Technology Research , Hubei Academy of Agricultural Sciences , Wuhan 430064 , China
| | - Zongjun Cui
- College of Agronomy and Biotechnology , China Agricultural University , Beijing 100193 , China
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Hou N, Wen L, Cao H, Liu K, An X, Li D, Wang H, Du X, Li C. Role of psychrotrophic bacteria in organic domestic waste composting in cold regions of China. BIORESOURCE TECHNOLOGY 2017; 236:20-28. [PMID: 28390273 DOI: 10.1016/j.biortech.2017.03.166] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/17/2017] [Revised: 03/24/2017] [Accepted: 03/28/2017] [Indexed: 06/07/2023]
Abstract
To study the influence of psychrotrophic bacteria on organic domestic waste (ODW) composting in cold regions, twelve new efficient psychrotrophic composting strains were isolated. Together with the published representative composting strains, a phylogenetic tree was constructed showing that although the strains belong to the same phylum, the genera were markedly different. The twelve strains were inoculated into the ODW in the composting reactor at 13°C. After treatment, the indices of temperature, moisture content, pH, electrical conductivity, C/N, ammonium nitrogen, and nitrate nitrogen indicated that the compost had reached maturity. The thermophilic phase was reached at 17d, and composting was completed at 42d, a markedly shorter composting time than that in previous studies. High-throughput sequencing indicated that the inoculative strains became the dominant community during the mesophilic phase and that they enhanced the stability of the microbial community structure. Thus, psychrotrophic bacteria played a key role in low-temperature composting.
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Affiliation(s)
- Ning Hou
- College of Resources and Environment, Northeast Agricultural University, Harbin 150030, Heilongjiang, PR China
| | - Luming Wen
- College of Resources and Environment, Northeast Agricultural University, Harbin 150030, Heilongjiang, PR China
| | - Huiming Cao
- College of Resources and Environment, Northeast Agricultural University, Harbin 150030, Heilongjiang, PR China
| | - Keran Liu
- College of Resources and Environment, Northeast Agricultural University, Harbin 150030, Heilongjiang, PR China
| | - Xuejiao An
- College of Resources and Environment, Northeast Agricultural University, Harbin 150030, Heilongjiang, PR China
| | - Dapeng Li
- College of Resources and Environment, Northeast Agricultural University, Harbin 150030, Heilongjiang, PR China
| | - Hailan Wang
- College of Resources and Environment, Northeast Agricultural University, Harbin 150030, Heilongjiang, PR China
| | - Xiaopeng Du
- College of Resources and Environment, Northeast Agricultural University, Harbin 150030, Heilongjiang, PR China
| | - Chunyan Li
- College of Resources and Environment, Northeast Agricultural University, Harbin 150030, Heilongjiang, PR China.
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Lacerda Júnior GV, Noronha MF, de Sousa STP, Cabral L, Domingos DF, Sáber ML, de Melo IS, Oliveira VM. Potential of semiarid soil from Caatinga biome as a novel source for mining lignocellulose-degrading enzymes. FEMS Microbiol Ecol 2016; 93:fiw248. [PMID: 27986827 DOI: 10.1093/femsec/fiw248] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Revised: 08/11/2016] [Accepted: 12/13/2016] [Indexed: 11/14/2022] Open
Abstract
The litterfall is the major organic material deposited in soil of Brazilian Caatinga biome, thus providing the ideal conditions for plant biomass-degrading microorganisms to thrive. Herein, the phylogenetic composition and lignocellulose-degrading capacity have been explored for the first time from a fosmid library dataset of Caatinga soil by sequence-based screening. A complex bacterial community dominated by Proteobacteria and Actinobacteria was unraveled. SEED subsystems-based annotations revealed a broad range of genes assigned to carbohydrate and aromatic compounds metabolism, indicating microbial ability to utilize plant-derived material. CAZy-based annotation identified 7275 genes encoding 37 glycoside hydrolases (GHs) families related to hydrolysis of cellulose, hemicellulose, oligosaccharides and other lignin-modifying enzymes. Taxonomic affiliation of genes showed high genetic potential of the phylum Acidobacteria for hemicellulose degradation, whereas Actinobacteria members appear to play an important role in celullose hydrolysis. Additionally, comparative analyses revealed greater GHs profile similarity among soils as compared to the digestive tract of animals capable of digesting plant biomass, particularly in the hemicellulases content. Combined results suggest a complex synergistic interaction of community members required for biomass degradation into fermentable sugars. This large repertoire of lignocellulolytic enzymes opens perspectives for mining potential candidates of biochemical catalysts for biofuels production from renewable resources and other environmental applications.
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Affiliation(s)
- Gileno V Lacerda Júnior
- Research Center for Chemistry, Biology and Agriculture (CPQBA), UNICAMP, Division of Microbial Resources, Zip code 13148-218, Paulínia, São Paulo, Brazil
| | - Melline F Noronha
- Research Center for Chemistry, Biology and Agriculture (CPQBA), UNICAMP, Division of Microbial Resources, Zip code 13148-218, Paulínia, São Paulo, Brazil
| | - Sanderson Tarciso P de Sousa
- Research Center for Chemistry, Biology and Agriculture (CPQBA), UNICAMP, Division of Microbial Resources, Zip code 13148-218, Paulínia, São Paulo, Brazil
| | - Lucélia Cabral
- Research Center for Chemistry, Biology and Agriculture (CPQBA), UNICAMP, Division of Microbial Resources, Zip code 13148-218, Paulínia, São Paulo, Brazil
| | - Daniela F Domingos
- Department of Bioengineering, University of California San Diego, La Jolla, CA 92093-0412, USA
| | - Mírian L Sáber
- Laboratory of Environmental Microbiology, Brazilian Agricultural Research Corporation, EMBRAPA Environment, Jaguariúna, Zip code 13820-000, Brazil
| | - Itamar S de Melo
- Laboratory of Environmental Microbiology, Brazilian Agricultural Research Corporation, EMBRAPA Environment, Jaguariúna, Zip code 13820-000, Brazil
| | - Valéria M Oliveira
- Research Center for Chemistry, Biology and Agriculture (CPQBA), UNICAMP, Division of Microbial Resources, Zip code 13148-218, Paulínia, São Paulo, Brazil
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Li P, Lin W, Liu X, Wang X, Luo L. Environmental Factors Affecting Microbiota Dynamics during Traditional Solid-state Fermentation of Chinese Daqu Starter. Front Microbiol 2016; 7:1237. [PMID: 27540378 PMCID: PMC4972817 DOI: 10.3389/fmicb.2016.01237] [Citation(s) in RCA: 87] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2016] [Accepted: 07/25/2016] [Indexed: 12/12/2022] Open
Abstract
In this study, we investigated the microbiota dynamics during two industrial-scale traditional solid-state fermentation (SSF) processes of Daqu starters. Similar evolution profiles of environmental parameters, enzymatic activities, microbial amounts, and communities were observed during the medium temperature SSF (MTSSF) and low temperature SSF (LTSSF) processes. Orders of Rickettsiales and Streptophyta only dominated the initial 2 days, and Eurotiales only predominated from days 10 to 24, however, phylotypes of Enterobacteriales, Lactobacillales, Bacillales, Saccharomycetales, and Mucorales both prevailed throughout the MTSSF and LTSSF processes. Nevertheless, the pH in MTSSF process on day 5 were 5.28, while in LTSSF process (4.87) significantly lower (P < 0.05). The glucoamylase activities in MTSSF process dropped from 902.71 to 394.33 mg glucose g(-1) h(-1) on days 5 to 24, while significantly lower (P < 0.05) in LTSSF process and decreased from 512.25 to 268.69 mg glucose g(-1) h(-1). The relative abundance of Enterobacteriales and Lactobacillales in MTSSF process constituted from 10.30 to 71.73% and 2.34 to 16.68%, while in LTSSF process ranged from 3.16 to 41.06% and 8.43 to 57.39%, respectively. The relative abundance of Eurotiales in MTSSF process on days 10 to 24 decreased from 36.10 to 28.63%, while obviously higher in LTSSF process and increased from 52.00 to 72.97%. Furthermore, lower bacterial richness but higher fungal richness were displayed, markedly differences in bacterial communities but highly similarities in fungal communities were exhibited, during MTSSF process comparatively to the LTSSF process. Canonical correspondence analysis revealed microbial structure transition happened at thermophilic stages under environmental stress of moisture, pH, acidity, and pile temperature. These profound understanding might help to effectively control the traditional Daqu SSF process by adjusting relevant environmental parameters.
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Affiliation(s)
- Pan Li
- Guangdong Key Laboratory of Fermentation and Enzyme Engineering, School of Bioscience and Bioengineering, South China University of Technology Guangzhou, China
| | - Weifeng Lin
- College of Light Industry and Food Sciences, South China University of Technology Guangzhou, China
| | - Xiong Liu
- Guangdong Key Laboratory of Fermentation and Enzyme Engineering, School of Bioscience and Bioengineering, South China University of Technology Guangzhou, China
| | - Xiaowen Wang
- Guangdong Key Laboratory of Fermentation and Enzyme Engineering, School of Bioscience and Bioengineering, South China University of Technology Guangzhou, China
| | - Lixin Luo
- Guangdong Key Laboratory of Fermentation and Enzyme Engineering, School of Bioscience and Bioengineering, South China University of Technology Guangzhou, China
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