Fermentation Bed Research Articles

Adhesive solid-state fermentation producing Aspergillus niger conidia on stainless-steel dixon ring supports.

An adhesive solid-state fermentation (adSSF) mode was developed to produce Aspergillus niger conidia, which used a stainless-steel Dixon ring as the support and water-retaining adhesive to load nutritional media on its surface. To obtain high conidia yields, the components of the water-retaining adhesive were screened, optimized by single-factor optimization and response surface methodology, and the optimal dosages of the main components were: wheat bran powder 0.023g·cm-3bed, cassava starch 0.0022g·cm-3bed, and xanthan gum 0.0083g·cm-3bed. The experimentally tested conidia yield was 4.2-fold that without water-retaining adhesive but was 3.7% lower than the maximum yield predicted by the model. The observed double-side growth of A. niger on the Dixon ring supports improved space utilization of the fermentation bed, and the void fraction can increase with the shrinkage of the gel layer. In 1.6L tray reactors with three-point online temperature monitoring, the inner-bed temperature of adSSF was at most 4°C lower than the adsorbed carrier solid-state fermentation (ACSSF) mode, and the conidia yield was 1.68 × 108 conidia.cm-3bed, 61.5% higher than that of the ACSSF bed at the same time, but when the fermentation time was extended to 168h, the conidia yield of the adSSF bed and ACSSF bed were close to each other. The results revealed that the high voidage of the adSSF bed was the main reason for low bed temperature, which can benefit the inner-bed natural convection and water evaporation.

Xanthomonas chitinilytica sp. nov., a novel chitinolytic bacterium isolated from a microbial fermentation bed material.

A Gram-stain-negative bacterium, H13-6T, was isolated from a microbial fermentation bed material collected from a pig farm located in Yan'an, Shaanxi, China. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain H13-6T was affiliated with the genus Xanthomonas and showed highest similarity to strain Xanthomonas maliensis M97T (98.38%), Xanthomonas prunicola CFBP 8353T (98.26%) and Xanthomonas oryzae ATCC 35933T (98.11%). The pairwise ortho Average Nucleotide Identity values and the digital DNA-DNA hybridization values between strain H13-6T and the other Xanthomonas species were all below their respective cut-offs. Two genes encoding for chitinase were found and the strain showed a strong chitin-degrading activity. The major fatty acids were Iso-C15:0 (55.9%), Antesio-C15:0 (7.4%) and Iso-C11:0 (5.5%) and the major polar lipids were diphosphatidylglycerol, phosphatidyglycerol and phosphatidylethanolamine. Based on the phenotypic properties and phylogenetic distinctiveness, Xanthomonas chitinilytica was proposed as a novel species of the genus Xanthomonas, with strain H13-6T (= CGMCC 1.61317T = NBRC 115641T) as type strain.

Temporal dynamics of microbial composition and antibiotic resistome in fermentation bed culture pig farms across various ages

The discharge from pig farms presents significant challenges to the environment and human health, specifically regarding the dissemination of antimicrobial resistance (AMR). Fermentation bed culture has emerged as an increasingly popular and environmentally friendly pig farming model in China, as it minimizes the release of harmful substances into the environment. However, there remains a limited understanding of the occurrence and dynamics of microbiome and antibiotic resistome in fermentation bed culture. Herein, we collected fermentation bed materials (FBM) from four fermentation bed culture pig farms with varying service ages and investigated their bacterial communities, antibiotic resistance genes (ARGs), mobile genetic elements (MGEs), metal resistance genes (MRGs) and potential antibiotic-resistant bacterial hosts through metagenomics. Pseudomonadota, Actinomycetota, Bacteroidota and Bacillota were identified as the dominant phyla present in the FBM. In total, we detected 258 unique ARGs in the FBM samples, with 79 core ARGs shared by all FBM samples, accounting for 95 % of the total ARG abundance. Our results revealed significant variations in microbial communities and ARG profiles across varying service ages of FBM. Compared to long-term FBW, short-term FBM exhibited higher numbers and abundances of ARGs, MRGs and MGEs, along with higher levels of potential bacterial pathogens and high-risk ARGs. Further analysis of metagenome-assembled genome (MAG) indicated that the putative hosts of ARGs primarily belonged to Pseudomonadota, Actinomycetota and Bacillota. Alarmingly, among the 80 recovered ARG-carrying MAGs, 23 MAGs encoded multi-resistance, including clinically significant species that require urgent attention. Overall, this study provided valuable insights into the temporal patterns of antibiotic resistome and bacterial communities within FBM, enhancing our understanding of FBM in pig farming. The findings could potentially contribute to the development of effective strategies for evaluating and regulating fermentation bed culture practices in pig farming.

Antibiotic resistome and associated bacterial communities in agricultural soil following the amendments of swine manure-derived fermentation bed waste.

The practice of utilizing animal manures on land is widespread in agriculture, but it has raised concerns about the possible spread of antibiotic resistance genes (ARGs) and thepotential risk it poses to public health through food production. Fermentation bed culture is an effective circular agricultural practice commonly utilized in pig farming that minimizes the environmental impact of livestock farming. However, this method generates a significant amount of fermentation bed waste (FBW), which can be turned into organic fertilizer for land application. The objective of this research was to examine the impacts of amending agricultural soil samples with swine manure-derived FBW on microbial communities, mobile genetic elements (MGEs), and ARG profiles over different periods. The study findings indicated that the amendment of swine manure-derived FBW significantly increased the diversity and abundance of ARGs and MGEs during the early stages of amendment, but this effect diminished over time, and after 12months of FBW amendments, the levels returned to those comparable to control samples. The shift in the bacterial communities played a significant role in shaping the patterns of ARGs. Actinobacteriota, Proteobacteria, and Bacteroidetes were identified as the primary potential hosts of ARGs through metagenomic binning analysis. Furthermore, thepH of soil samples was identified as the most important property in driving the composition of the bacterial community and soil resistome. These findings provided valuable insights into the temporal patterns and dissemination risks of ARGs in FBW-amended agriculture soil, which could contribute to the development of effective strategies to manage the dissemination risks of FBW-derived ARGs.

Evaluation of gaseous and solid waste in fermentation bedding system and its impact on animal performance: A study of breeder ducks in winter.

In order to further optimize the application of fermentation bedding system and evaluate its improvements on low temperature, low humidity and other adverse environments of animal breeding in winter, we tested the waste discharge and performance of 12,921 breeder ducks from November to January. The fresh bedding materials and fermentation microbes showed significant advantages. They increased the temperature and temperature humidity index (THI) by more than 3.48 °C and 5.54, reduced the emissions of H2S, NH3, CO2, fine particulate matter (PM2.5), coarse particulate matter (PM10) and total suspended particulate (TSP) by more than 29.92%, 47.21%, 13.69%, 25.90%, 23.43% and 25.94% respectively, compared to control. The stale bedding materials increased the mortality rate and breeding egg loss rate of breeder ducks by 0.17% and 4.22% significantly, reduced the healthy duckling rate and total effective hatching rate by 2.41% and 4.22%, compared to control, had limited effects on the improvement of house environments. PM2.5, TSP, CO2, H2S and NH3 were important environmental parameters affecting the productive and reproductive performance of ducks. These data can provide an insight that the fermentation bed system could reduce the waste emission of breeder ducks, improve their production and increase the health rate of their offspring. Its application in livestock farming would create a better breeding environment and economic benefits. In addition, the stale bedding materials were not recommended to recycle in fermentation bed system for cleaner production and sustainable development.

Sphingopyxis yananensis sp. nov., a novel 2-nitropropane degrading bacterium isolated from a microbial fermentation bed substrate.

A rod-shaped, Gram-negative staining strain, FBM22T, was isolated from a microbial fermentation bed substrate from a pig farm. Its colonies appeared yellow and were 0.5-1.2mm in diameter. Cells were 0.3-0.5μm wide, 0.5-0.83μm long. Optimal growth occurred at 30°C and pH 7.0-8.0; NaCl was not required for growth. The strain performed denitrification and nitrate reduction functions. And it could produce catalase. FBM22-1T utilized the following organic substrates for growth: tyrosine, glutamic acid, D-glucose, and galactose. The novel isolate could degrade 2-nitropropane as carbon and nitrogen source. The dominant respiratory quinone was Q-10. The major polar lipids were diphosphatidylglycerol, phosphatidylcholine and phosphatidylethanolamine. C18:1 ω7c, C16:1 ω7c and/ or C16:1 ω6c, and C14:0 2-OH were the major (≥ 8%) fatty acids. The G+C content was 56.8mol%. FBM22T was found to be a member of the genus Sphingopyxis in the family Sphingomonadaceae of the class Alphaproteobacteria. It had the highest sequence similarity with the type strains Sphingopyxis terrae subsp. ummariensis UI2T (96.47%) and Sphingopyxis terrae subsp. terrae NBRC 15098T (96.40%). Furthermore, FBM22T had 18.7% and 18.4% relatedness (based on digital DNA-DNA hybridization) with its two relatives (S. terrae subsp. ummariensis UI2T and S. terrae subsp. terrae NBRC 15098T). The morphological, physiological, and genotypic differences identified in this study support the classification of FBM22T as a novel species within the genus Sphingopyxis, for which the name Sphingopyxis yananensis sp. nov. is proposed. The type strain is FBM22T (= KCTC 82290T = CCTC AB2020286T).

Rhodococcus yananensis sp. nov., a novel denitrification actinobacterium isolated from microbial fermentation bed material from a pig farm.

An opaque, pink-coloured, gram-positive, aerobic bacteria (designated as FBM22-1T), was isolated from microbial fermentation bed material from a pig farm in northwestern China. Optimal growth occurred at 30-37 °C, pH 7.0 and with 0.5 % NaCl (w/v). The strain had nitrification and denitrification functions. Phylogenetic analysis based on 16S rRNA gene sequences revealed that the novel isolate belonged to the genus Rhodococcus. Strain FBM22-1T was closely related to Rhodococcus zopfii NBRC 100606T and Rhodococcus rhodochrous NBRC 16069T, with 16S rRNA gene sequence similarities of 97.9 and 97.7 %, respectively. The predominant menaquinone in strain FBM22-1T was MK-8(H2). The cellular fatty acids consisted primarily of C16 : 1ω7c and/or C16 : 1 ω6c, C16 : 0 and 10-methyl C18 : 0. The major polar lipids were diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine and glycolipid. The G+C content of strain FBM22-1T was 68.64 mol%. Based on the phenotypic, phylogenetic and chemotaxonomic characterization results, in combination with low values of digital DNA-DNA hybridization between strain FBM22-1T and its closest neighbours, FBM22-1T represents a novel species of the genus Rhodococcus, for which the name Rhodococcus yananensis sp. nov. is proposed; the type strain is FBM22-1T (=KCTC 49502T=CCTCC AB2020275T).

Influences of human waste-based ectopic fermentation bed fillers on the soil properties and growth of Chinese pakchoi.

The reuse of human wastes as biofertilizer resources offers a new option for meeting the growing demand for food and addressing poor soil productivity. Feces and black water are ubiquitous human wastes that usually require proper treatment, such as composting and anaerobic digestion, to remove potentially harmful substances before they can be applied as fertilizers. As an effective treatment technology for livestock farming wastes, the ectopic fermentation bed system (EFS) provides a new means of treating human waste and producing organic fertilizer from decomposed filler. Therefore, the objective of this study was to evaluate and compare the nutrient content and fertilizer potential of decomposed fillers obtained after EFS treatment of human feces and black water under different application conditions. The results showed that the application of fillers increased the yield of pakchoi by 3.60⁓29.32% and nutrient uptake by 8.09⁓83.45% compared to the CK, which could effectively promote the growth of pakchoi. This approach also improved the quality of pakchoi and enhanced soil fertility, and differences were observed in the effects of different kinds and application amounts of fillers. Soil EC was the soil property that had the greatest effect on the growth characteristics of pakchoi in this study. These findings help to better clarify the agronomic value of human wastes, but the effects of long-term filler application need to be further explored.

Effect of fermentation bed on bacterial growth in the fermentation mattress material and cecum of ducks.

The composition of microorganisms in the gastrointestinal tract is closely related to the intestinal microenvironments and the exterior growth environments of host. In this study, 16S rDNA sequencing technology was adopted to investigate the influence of fermentation bed on the cecum microorganisms of ducks. Two feeding density treatment groups were set up, including group A (n = 4brids/m2) and group B (n = 6brids/m2). Samples were collected from the intermediate core fermentation layer (10-20cm) of the fermented mattress materials and from the intestinal contents of ducks at 4, 6 and 8weeks, respectively. Results showed that Bacteroidetes (20.12-27.17%) and Ruminococcaceae UCG-014 (2.97-10.1%) were the predominant microorganisms in duck cecum, while the Truepera (5.08-6.29%), Pricia (4.44-5.44%) and Luteimonas (3.62-4.99%) were the dominant microorganisms in fermentation mattress material. The cecum bacteria exhibited great difference among different growth periods of the ducks. Increasing the stocking density of ducks had a negative effect on the beneficial bacteria in the cecum. The microbial populations in fermentation mattress material were very different from that in the cecal. In summary, our findings can provide a scientific data for the rational use of fermentation bed feeding mode in poultry production.

Microbial community and function in nitrogen transformation of ectopic fermentation bed system for pig manure composting

In this work, agricultural wastes were treated by composting in an ectopic fermentation bed system (EFBS) with a continuous nitrogen addition technique. With decreasing of NH4+-N concentration and increasing of NO3−-N concentration were observed, and activities of protease, urease and nitrate reductase changed significantly during the fermentation process. To elucidate the key microbes and their function in nitrogen-transforming, microbial diversity and clusters of orthologous groups (COGs) in composting materials were evaluated using metagenomic technology. Comparing with ammonification, the COGs involved in nitrification and denitrification were predominant in the composts. The correlation heatmap revealed that Streptomyces predominant in ammonification was significantly affected by contents of N, NH4+-N and NO3−-N. Meanwhile, ammonia-oxidizing archaea (AOA) had a positive relationship with moisture. The most abundant genera in denitrification had positive relationships with N and NO3−-N. The results indicated that EFBS had functionally diverse microbes and COGs for NH3 removal.

Handheld Electronic Nose (HEN) for Detection of Optimum Fermentation Time during Tea Manufacture and Assessment of Tea Quality

Fermentation is an important process in tea manufacturing cycle and proper fermentation of tea leaves determines the quality of made tea. Both over and under fermentation affects the quality of made tea. To understand the optimum fermentation time and flavour of the processed tea, CDAC Kolkata had developed a hand-held electronic nose system (HEN). The system consists of top, mid and bottom section. Top section contains major portion of electronics, display, pump, sensor array and battery. The detachable mid-section holds the valve and provides an air path between pump and sample holder and between sample holder and sensor array. The bottom section is a threaded glass jar that acts as the sample holder. The HEN can be handy in determining the optimum fermentation end point during manufacturing process and to assess the quality of processed tea based on its aroma. Fixed quantity (half of the sample holder) of sample was taken from fermentation bed at an interval of five minutes and the generated aroma volatiles were discharged to the sensor array. The captured aroma was plotted against time to get the second aroma peak, which determined the optimum end point of fermentation. This was compared with the existing chemical method. The results obtained through HEN were correlated with the existing chemical method. The processed teas consisting CTC and orthodox types of manufacture and different grades were evaluated through HEN and the results were compared with organoleptic evaluation of tea by national and international tea tasters. The results revealed that the Handheld Electronic Nose is a suitable instrument for determining the optimum fermentation time during tea manufacture based on aroma.

Concentrations and emissions of particulate matter and ammonia from extensive livestock farm in South China.

Atmospheric particulate matter (PM) and ammonia pollution from livestock feeding have gradually become the environmental concerns due to the spring up of livestock farms in worldwide. However, researches about the formation of atmospheric particulate matter related to ammonia are still limited. Therefore, a study to survey the total suspended particles (TSP), PM with the diameter less than 10μm (PM10), PM4, PM2.5, PM1, and ammonia was conducted at four types of hog houses distinguished by its building design as well as manure handling methods in South China. Four hog houses were monitored during three fattening periods from 2016 to 2017. The emissions of NH3 per hog house averaged 210.42μgs-1. The emissions of PM per hog house averaged 2.017μgh-1 for PM1, 2.149μgh-1 for PM2.5, 2.305μgh-1 for PM4, 3.950μgh-1 for PM10, and 9.317μgh-1 for TSP. The emissions of PM per hog house average 2.017μgh-1, 2.149μgh-1, 2.305μgh-1, 3.950μgh-1, and 9.317μgh-1, respectively for PM1, PM2.5, PM4, PM10, and PM10. In each hog house, while the quantity of manure determined the concentration of NH3, biological fermentation bed was able to control the ammonia volatilization compared with other three manure handling methods. The largest percentage of fine PM (< 10μm) is produced by the manual waterless method for manure handling. When it came to the manual waterless method, largest amount of fine PM (< 10μm) was founded to form. Among various contributions of secondary inorganic PM to PM1, the NH3 was a dominant factor. Based on our experiment, the absolute concentration of NH3 was inversely proportional to the concentration of PM1 when the background influence was removed.

Diversity and dynamics of the bacterial community involved in pig manure biodegradation in a microbial fermentation bed system

Overproduction of livestock manures with unpleasant odors causes significant environmental problems. The microbial fermentation bed (MFB) system is considered an effective approach to recycling utilization of agricultural byproducts and pig manure (PM). To gain a better understanding of bacterial communities present during the degradation of PM in MFB, the PM bacterial community was evaluated at different fermentation stages using 16S rRNA high throughput sequencing technology. The heatmap plot clustered five samples into short-term fermentation stage of 0–10 days and long-term fermentation stage of 15–20 days. The most abundant OTUs at the phylum level were Firmicutes, Actinobacteria and Proteobacteria in the long-term fermentation stage of PM, whereas Firmicutes, Bacteroidetes, and Proteobacteria predominated in the short-term fermentation stage of PM. At the genus level, organic degradation strains, such as Corynebacterium, Bacillus, Virgibacillus, Pseudomonas, Actinobacteria, Lactobacillus, Pediococcus were the predominate genera at the long-term fermentation stage, but were found only rarely in the short-term fermentation stage. C/N ratios increased and the concentration of the unpleasant odor substance 3-hydroxy-5-methylisoxazole (3-MI) decreased with prolonged period of fermentation. Redundancy analysis (RDA) demonstrated that the relative abundance of Firmicutes, Actinobacteria, Acidobacteria and Proteobacteria had a close relationship with degradation of 3-MI and increasing C/N ratio. These results provide valuable additional information about bacterial community composition during PM biodegradation in animal husbandry.

养猪微生物发酵床芽胞杆菌空间分布多样性

PDF HTML阅读 XML下载 导出引用 引用提醒 养猪微生物发酵床芽胞杆菌空间分布多样性 DOI: 10.5846/stxb201607261528 作者: 作者单位: 作者简介: 通讯作者: 中图分类号: 基金项目: 国家自然科学基金（31370059）；福建省自然科学基金（2016J01129）；福建省公益项目（2015R1018-7）；农业部948项目（2016-X21） Spatial distribution pattern and community diversity of the Bacillus-like species in a fermentation bed system for pig rearing Author: Affiliation: Fund Project: 摘要 | 图/表 | 访问统计 | 参考文献 | 相似文献 | 引证文献 | 资源附件 | 文章评论 摘要:了解微生物发酵床大栏养猪垫料中的芽胞杆菌多样性和空间分布规律，为微生物发酵床管理、芽胞杆菌新资源挖掘及菌剂开发奠定基础。将发酵床划分为32个方格（4行 × 8列），采用五点取样法获得每个方格的样品。采用可培养法从32份样品中分离芽胞杆菌菌株，利用16S rRNA基因序列初步鉴定所分离获得的芽胞杆菌种类。利用聚集度指标和回归分析法，分析芽胞杆菌的样方空间分布型。通过Shannon-Wiener多样性指数、Simpson优势度指数、Hill指数及丰富度指数分析，揭示微生物发酵床中芽胞杆菌的空间分布多样性。从32份样品中共获得芽胞杆菌452株，16S rRNA基因鉴定结果表明它们分别隶属于芽胞杆菌纲的2个科、8个属、48个种。其中，种类最多的为芽胞杆菌属（Bacillus），30种；赖氨酸芽胞杆菌属（Lysinibacillus），6种；类芽胞杆菌属（Paenibacillus），5种；短芽胞杆菌属（Brevibacillus），3种；鸟氨酸芽胞杆菌属（Ornithinibacillus）、大洋芽胞杆菌属（Oceanibacillus）、少盐芽胞杆菌属（Paucisalibacillus）和纤细芽胞杆菌属（Gracilibacillus）各1个种。芽胞杆菌种类在发酵床空间分布差异很大，根据其空间出现频次，可分为广分布种类，如地衣芽胞杆菌（Bacillus licheniformis）；寡分布种类，如根际芽胞杆菌（B. rhizosphaerae）；少分布种类，如弯曲芽胞杆菌（B. flexus）。依据其数量，可分为高含量组优势种群，如地衣芽胞杆菌（B. licheniformis）；中含量组常见种群，耐盐赖氨酸芽胞杆菌（Lysinibacillus halotolerans）；寡含量组寡见种群，如根际芽胞杆菌（B. rhizosphaerae）；低含量组偶见种群，如土地芽胞杆菌（B. humi）。空间分布型聚集度和回归分析测定表明，芽胞杆菌在微生物发酵床的分布类型为聚集分布。微生物发酵床垫料中芽胞杆菌种类总含量高达4.41×108 个/g，其种类含量范围为0.01-94.1×106 个/g（均值为8.96×106 个/g），丰富度指数（D）、优势度指数（λ）、Shannon-Wiener指数（H'）和均匀度指数（J'）分别为0.4928、0.2634、1.3589和0.9803，其中香农指数最大的单个芽胞杆菌种类为地衣芽胞杆菌（B. licheniformis）。根据芽胞杆菌种类多样性指数聚类分析，当欧式距离λ=17时，可分为高丰富度高含量和低丰富度低含量类型。微生物发酵床的芽胞杆菌种类丰富、数量高，是一个天然的菌剂"发酵罐"，有望直接作为微生物菌剂，应用于土壤改良、作物病害防控、污染治理等领域。 Abstract:To provide a foundation for the management of microbial fermentation beds, new resource mining of Bacillus-like species, and development of microbial agents, we investigated the spatial distribution pattern and community diversity of Bacillus-like species in the litters of a pig-on-litter system. The microbial fermentation bed was divided into 32 square areas of 4 rows × 8 columns. A sample from each area was obtained using a five-point sampling mode. Bacillus-like bacteria were isolated from the 32 samples using a culture method and preliminarily identified based on 16S rRNA gene sequences. The spatial distribution pattern of the Bacillus-like bacteria was analyzed using a concentration index and regression analysis. Moreover, the Shannon-Wiener diversity index, Simpson dominance index, Hill index, and richness were separately calculated to reveal the community structure and diversity of the Bacillus-like bacteria in the microbial fermentation bed. A total of 452 Bacillus-like isolates were obtained from the 32 litter samples, and identified as 48 species belonging to eight genera and two Families (Bacillaceae and Paenibacillaceae) within the Bacilli by 16S rRNA gene sequences. The species numbers for the genera were as follows: 30 for Bacillus, six for Lysinibacillus, five for Paenibacillus, three for Brevibacillus, and one for each of Ornithinibacillus, Oceanobacillus, Paucisalibacillus, and Gracilibacillus. There was a large difference in the distribution of Bacillus-like species in the fermentation bed. On the basis of their occurrence frequency, the Bacillus-like species could be discriminated as the widespread species, including Bacillus licheniformis; sparsely distributed species, including B. rhizosphaerae; and rare species, including B. flexus. According to the abundance of each species, the Bacillus-like species could be classified into the high-content dominant populations, including B. licheniformis; medium-content common populations, including Lysinibacillus halotolerans; oligocontent oligo populations, including B. rhizosphaerae, and low-content occasional populations, including B. humi. The concentration class and regression analysis results indicated that the spatial distribution pattern of the Bacillus-like species in the microbial fermentation bed was an aggregated distribution. In the litters, the content range, total content, richness, Simpson index, Shannon-Wiener index, and Pielou's evenness index of the Bacillus-like species were 0.01-94.1 × 106 cfu/g, 4.41 × 108 cfu/g, 0.4928, 0.2634, 1.3589, and 0.9803, respectively. Moreover, B. licheniformis appeared to have the highest Shannon-Wiener index value. On the basis of the diversity index cluster analysis, all the Bacillus-like species could be divided into a high richness high content group and a low richness low content group. The Bacillus-like bacteria can actively inhabit microbial fermentation beds and have rich species and abundant contents. Thus, the microbial fermentation bed can be considered as a natural bacterial "fermentation tank", which is expected to be directly used as a microbial inoculum and applied in the fields for purposes including soil improvement, crop disease prevention and control, and pollution management. 参考文献 相似文献 引证文献

Microbacterium sorbitolivorans sp. nov., a novel member of Microbacteriaceae isolated from fermentation bed in pigpen.

Two bacterial strains SZDIS-1-1T and GZDIS-1-1 were isolated from fermentation bed of a pigpen in Fujian Province, China. Cells were Gram-stain-positive, facultatively anaerobic, short rods without flagellum. Their nearest phylogenetic neighbours were Microbacterium amylolyticum N5T (16S rRNA gene sequence similarity 98.2 %), Microbacterium indicum BBH6T (97.9 %) and Microbacterium gubbeenense DPC 5286T (97.8 %) with the DNA-DNA hybridization values to strain SZDIS-1-1T as 20.0±1.2, 14.3±5.8 and 19.1±1.6 %, respectively. The DNA G+C content of the new isolates was 67.6-71.1 mol% and anteiso-C15 : 0, anteiso-C17 : 0 and iso-C16 : 0 were their predominant cellular fatty acids. These results were consistent with classification into the genus Microbacterium. However, cell-wall sugars and characteristic amino acid were rhamnose, glucose, galactose and ornithine. Major menaquinones were MK-11 and MK-10. The polar lipids consisted of diphosphatidylglycerol, phosphatidylglycerol, glycolipids, unknown phospholipid and unknown lipids. These characteristics constructed a distinct profile of the two isolates. Therefore, based on polyphasic taxonomic characteristics, strains SZDIS-1-1T and GZDIS-1-1 represented a novel species of genus Microbacterium, for which the name Microbacterium sorbitolivorans sp. nov. is proposed, with strain SZDIS-1-1T (=CGMCC 1.15228T=DSM 103422T) as the type strain.

Dissemination of antibiotic resistance genes and their potential removal by on-farm treatment processes in nine swine feedlots in Shandong Province, China

This work investigated the dissemination of antibiotic resistance genes (ARGs) encoding resistance to sulfonamide and tetracycline antibiotics in nine swine feedlots located in Shandong Province of China, and examined their potential removal by various on-farm treatment processes. Results indicate that the target ARGs were widely distributed in swine wastes, with mean relative abundances ranging from 3.3 × 10−5 (tetC) to 5.2 × 10−1 (tetO) in swine manure and from 7.3 × 10−3 (tetC) to 1.7 × 10−1 (tetO) in swine wastewater. The mean relative ARG abundances ranged from 9.9 × 10−5 (tetW) to 1.1 × 10−2 (tetO) in soils and from 3.1 × 10−4 (tetW) to 1.1 × 10−2 (sul2) in receiving river sediments, indicating that the farmland application of swine manure compost and the discharge of swine wastewater promoted the dissemination of ARGs into adjacent environments. Microbial fermentation bed (MFB) could reduce the relative ARG abundances by 0–1.18 logs. However, septic tank, biogas digester and natural drying methods were relatively ineffective for ARG removal, and the relative abundances of some ARGs (i.e., tetC, tetG, sul1, and sul2) even increased by 0.74–3.90 logs in treated wastes. Bacterial diversity analysis indicates that the evolution of bacterial communities in the MFB played a crucial role in eliminating the ARGs. This study helps the effective assessment and management of ecological risks arising from ARGs in swine feedlots.

Food Waste Composting Study from Makanan Ringan Mas

The poor management of municipal solid waste in Malaysia has worsened over the years especially on food waste. Food waste represents almost 60% of the total municipal solid waste disposed in the landfill. Composting is one of low cost alternative method to dispose the food waste. This study is conducted to compost the food waste generation in Makanan Ringan Mas, which is a medium scale industry in Parit Kuari Darat due to the lack knowledge and exposure of food waste recycling practice. The aim of this study is to identify the physical and chemical parameters of composting food waste from Makanan Ringan Mas. The physical parameters were tested for temperature and pH value and the chemical parameter are Nitrogen, Phosphorus and Potassium. In this study, backyard composting was conducted with 6 reactors. Tapioca peel was used as fermentation liquid and soil and coconut grated were used as the fermentation bed. Backyard composting was conducted with six reactors. The overall results from the study showed that the temperature of the reactors were within the range which are from 30° to 50°C. The result of this study revealed that all the reactors which contain processed food waste tend to produce pH value within the range of 5 to 6 which can be categorized as slightly acidic. Meanwhile, the reactors which contained raw food waste tend to produce pH value within the range of 7 to 8 which can be categorized as neutral. The highest NPK obtained is from Reactor B that process only raw food waste. The average value of Nitrogen is 48540 mg/L, Phosphorus is 410 mg/L and Potassium is 1550 mg/L. From the comparison with common chemical fertilizer, it shows that NPK value from the composting are much lower than NPK of the common chemical fertilizer. However, comparison with NPK of organic fertilizer shown only slightly difference value in NPK.

Assessment of subsidies to minimize environmental pollution by Intensive Hog Feeding Operation (IHFO)

Environmental pollution caused by Intensive Hog Feeding Operations (IHFO) has long been an issue of common concern worldwide. The research constructs a theoretical framework development for the technological implementation of IHFO with Biogas project Subsidy, Fermented Bed Subsidy and Sewage Charge in the Government Policy design. Linear Programming method is used to simulate the impacts of policy variables on the manure disposal of IHFO. The result finds that: only above the threshold, that the Biogas subsidy is increased by 200 Yuan per head or the Fermented Bed subsidy by 100 Yuan per head, can policy variables play effective impact on the decision of manure disposal technology, and the maximal social benefit is achieved. Under the current subsidy policy, response of producers differs in the scale of Hog Farms. Biogas project subsidy can play roles in large-scale Hog Farms, while the litter subsidy of Fermented Bed plays mainly in small and medium-scale Hog Farms. The existing subsidy intensity needs to be strengthened in order to achieve maximum social benefit. An improvement of levying method and intensity of sewage charge will be able to stimulate producers' emphasis on manure disposal, increasing the implementation effect of subsidy policy.

Establishment and optimization of microbial 16S rDNA PCR reaction conditions in fermentation bed padding material.

Establishment and optimization of microbial 16S rDNA PCR reaction conditions in fermentation bed padding material.

Bio-functional pickles that reduce blood pressure of rats.

Addition of γ-aminobutyric acid (GABA) and angiotensin converting enzyme (ACE)-inhibitory peptides to the pickles was studied in order to develop a new type of pickles that reduce blood pressure. Based on the outcome of these studies, a new type of fermentation bed composed of rice bran and white miso has been successfully developed. The advantage of such pickles is that they not only contain both GABA and ACE-inhibitory peptides, but also that their taste and flavor are excellent, with colors close to the original ones. The new type of pickles could temporarily reduce blood pressure in two types of rats, spontaneously hypertensive rats and NaCl-sensitive model rats. Thus, the newly developed pickles appear to be beneficial for pickle business.