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Search Results: 1 - 10 of 4023 matches for " anaerobic fungi "
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Comparative study of cellulolytic activity of three rumen fungi on different substrates
Atanasova-Pan?evska Natalija,Kungulovski D?oko,Kungulovski Ivan
Zbornik Matice Srpske za Prirodne Nauke , 2011, DOI: 10.2298/zmspn1120315a
Abstract: Anaerobic chytridiomycete fungi are found in the gastrointestinal tracts of many domesticated ruminant and nonruminant herbivores and of a wide variety of wild herbivorous mammals. They produce high levels of cellulases and hemicellulases; these enzymes are regulated by substrate (especially soluble sugars) available to the organisms. The aim of this paper was to do a comparative study of cellulolytic activity of three rumen fungi on carboxymethyl cellulose and Avicel. The capacity of enzymes was determined by monitoring the growth on carboxymethyl cellulose (CMC) and Avicel. Enzyme activity was detected extracellularly in culture supernatants after vegetative growth. All of the isolates degraded CMC and avicel, and exhibited cellulolytic activities (carboxymethyl cellulose-(CMC-ase) and avicelase).
Degradation of Dry Matter and Fiber of Five Feeds by Rumen Anaerobic Fungi of Sheep
T. Ghoorchi,S. Rahimi,M. Rezaeian,G. R. Ghorbani
Journal of Science and Technology of Agriculture and Natural Resources , 2003,
Abstract: An experiment was carried out to estimate the potential activity of rumen anaerobic fungi in the degradation of dry matter and fiber of feeds. Samples of wheat bran, bagasse, cotton seed, alfalfa and corn silage were used as the substrates to culture rumen fungi which were isolated from a fistulated Shal sheep. Loss percentages of dry matter (DML), neutral detergent fiber (NDF), acid detergent fiber (ADF), acid detergent (ADL), cellulose, and hemicellulose of samples were measured after 0, 3, 6 and 9 days of incubation. Dry matter and NDF loss of substrates varied from 10.6 % to 29.4% and 11.7% to 48.7% after 9 days of fungi growth. The highest and lowest DML and NDF were related to alfalfa and bagasses, respectively. The highest values for the ADF loss (39%), hemicellulose loss (65.6%) and cellulose loss (55.6%) were measured from alfalfa. The results indicated that rumen anaerobic fungi have the ability of degrading dry matter and fiber from different types of feed.
Fungos anaeróbios do rúmen de bovinos e caprinos de corte criados em pastagens tropicais
Abr?o, F.O.;Barreto, S.M.P.;Geraseev, L.C.;Duarte, E.R.;
Arquivo Brasileiro de Medicina Veterinária e Zootecnia , 2010, DOI: 10.1590/S0102-09352010000300036
Abstract: the presence of anaerobic fungi structures was evaluated in ruminal juice of beef goats and beef cattle raised in the north of minas gerais, brazil. the strains were collected from 18 anglo-nubian crossbred male goats and 23 nellore crossbred steers during the dry period of the year. physical-chemical characteristics of the juice were evaluated and direct examination with koh digestion was performed for anaerobic fungi detection. structures of these fungi were detected in samples of 14 (77.8%) goats and 17 (73.9%) steers. the monocentric fungi frequency (56.5%) was significantly higher in cattle than polycentric fungi frequency (26.1%). this study is the first report of anaerobic ruminal fungi in these ruminants in brazil and showed high prevalence of theses microorganisms in the ruminal ecosystem of both animals.
Digestive tract microbiota in healthy volunteers
Zilberstein, Bruno;Quintanilha, Alina G;Santos, Manoel A A;Pajecki, Denis;Moura, Eduardo G;Alves, Paulo Roberto Arruda;Maluf Filho, Fauze;Souza, Jo?o Ary Ubriaco de;Gama-Rodrigues, Joaquim;
Clinics , 2007, DOI: 10.1590/S1807-59322007000100008
Abstract: purpose: the aim of this study was to standardize the methods of sample collection of mucus from the digestive tract and to determine the microbiota in healthy volunteers from brazil, collecting samples from the mouth, esophagus, stomach, duodenum, jejunum, ileum, colon, and rectum. methods: microbiota of selected healthy volunteers from the oral cavity (n=10), the esophagus (n=10), the upper digestive tract (n=20), and the lower digestive tract (n=24) were evaluated through distinct collection methods. collection methods took into account the different sites, using basic scraping and swabbing techniques, stimulated saliva from the oral cavity, irrigation-aspiration with sterile catheters especially designed for the esophagus, a probe especially designed for upper digestive tract, and a special catheter for the lower digestive tract. results: (i) mixed microbiota were identified in the oral cavity, predominantly gram-positive aerobic and anaerobic cocci; (ii) transitional flora mainly in the esophagus; (iii) veillonella sp, lactobacillus sp, and clostridium sp in the stomach and duodenum; (iv) in the jejunum and upper ileum, we observed bacteroides sp, proteus sp, and staphylococcus sp, in addition to veillonella sp; (v) in the colon, the presence of "nonpathogenic" anaerobic bacteria veillonella sp (average 105 ufc) indicates the existence of a low oxidation-reduction potential environment, which suggests the possibility of adoption of these bacteria as biological markers of total digestive tract health. conclusions: the collection methods were efficient in obtaining adequate samples from each segment of the total digestive tract to reveal the normal microbiota. these procedures are safe and easily reproducible for microbiological studies.
Oropharynx microbiota among alcoholics and non-alcoholics
Golin, Valdir;Mimica, Igor Mimica;Mimica, Lycia Mara Jeanne;
Sao Paulo Medical Journal , 1998, DOI: 10.1590/S1516-31801998000300007
Abstract: context: the oropharynx microbiota plays an important role in the origin of infections, especially among alcoholics whose airway defenses are impaired. objective: to compare the normal oropharingeal flora in heavy alcohol drinker and non-alcoholics. patients: 117 persons, 58 heavy alcohol drinkers and 59 non-alcoholics. setting: santa casa de s?o paulo emergency service. design: a blind prospective study. main outcomes measures: prevalence of aerobic and anaerobic bacteria, and fungi. results: the study of the oropharynx microbiota among heavy alcohol drinkers demonstrated the presence of anaerobic microorganisms in 84.5% of them, including: bacteroides sp, prevotella melaninogenica, fusobacterium sp, veilonella sp, peptostreptococcus sp, propionibacterium sp, bifidobacterium sp and clostridium sp, versus 30.5% (p<0.005) of non-alcoholics. candida sp was present in 34.5% of heavy alcohol drinkers and 5.1% of non-alcoholics (p<0.005). enterobacteria predominated among heavy alcohol drinkers (25%) compared with non-alcoholics (5.5%) only in the age group 14 to 34 years (p<0.05). conclusion: based upon these results, it was possible to conclude that the knowledge of the oropharynx microbiota among heavy drinkers and non-alcoholics has an important predictive value concerning probable etiologic agents of lower airway infections. infections caused by anaerobic microorganisms and fungi should be taken into consideration during the choice of empirical therapy for heavy alcohol drinkers.
Complete Detoxification of Olive Mill Wastewaters by Integrated Treatment Using the White Rot Fungus Phanerochaete chrysosporium Followed by Anaerobic Digestion and Ultrafiltration
Abdelhafidh Dhouib,Fathi Aloui,Naima Hamad,Sami Sayadi
Biotechnology , 2005,
Abstract: In this study, we investigated an integrated technology for the treatment of the recalcitrant contaminants of OMW, allowing water recovery and reuse for agricultural purposes. We have developed a pilot plant based on fungal pretreatment using Phanerochaete chrysosporium followed by anaerobic digestion. P. chrysosporium DSM 6909 was cultivated on pre-stored OMW as sole carbon and energy sources in a 120 L Air Lift Reactor (ALR) in a semi-continuous feed of OMW at a Hydraulic Retention Time (HRT) of 3 to 5 days. The P. chrysosporium DSM 6909 pre-treated OMW was fed in a 300 l anaerobic filter after a decantation step. The anaerobic filter was loaded with undiluted pre-treated OMW at a starting loading rate of 2-3 g of COD per litre of reactor and per day. The COD loading was increased when no apparent toxicity was encountered. This anaerobic reactor worked continuously for 6 months at loading rates reaching 7 g L-1 d-1 of COD without any apparent toxicity. The percentages of inhibition of Vibrio fisheri luminescence after exposure to OMW showed that compared to the 100% inhibition of untreated OMW, P. chrysosporium DSM 6909 decreased the relative toxicity to 74%. Consequently, the P. chrysosporium DSM 6909 pre-treated OMW was well converted into biogas by anaerobic digestion which resulted in an effluent with 38% toxicity referred to as untreated OMW. Moreover, the use of ultrafiltration (UF) as post-treatment technology completely detoxified the anaerobic effluent and removed its black color. Results showed that compared to irrigation with water, treated effluent increased the Germination Index (GI) of Lycopersicon esculentum and enhanced plant growth while diluted untreated OMW decreased the GI and caused a pronounced growth inhibition.
Two-Stage Fungal Pre-Treatment for Improved Biogas Production from Sisal Leaf Decortication Residues
Mutemi Muthangya,Anthony Manoni Mshandete,Amelia Kajumulo Kivaisi
International Journal of Molecular Sciences , 2009, DOI: 10.3390/ijms10114805
Abstract: Sisal leaf decortications residue (SLDR) is amongst the most abundant agroindustrial residues in Tanzania and is a good feedstock for biogas production. Pretreatment of the residue prior to its anaerobic digestion (AD) was investigated using a twostage pre-treatment approach with two fungal strains, CCHT-1 and Trichoderma reesei in succession in anaerobic batch bioreactors. AD of the pre-treated residue with CCTH-1 at 10% (wet weight inoculum/SLDR) inoculum concentration incubated for four days followed by incubation for eight days with 25% (wet weight inoculum/SLDR) of T. reesei gave a methane yield of 0.292 ± 0.04 m3 CH4/kg volatile solids (VS)added. On reversing the pre-treatment succession of the fungal inocula using the same parameters followed by AD, methane yield decreased by about 55%. Generally, an increment in the range of 30–101% in methane yield in comparison to the un-treated SLDR was obtained. The results confirmed the potential of CCHT-1 followed by Trichoderma reesei fungi pre-treatment prior to AD to achieve significant improvement in biogas production from SLDR.
Functional characterization of cellulases identified from the cow rumen fungus Neocallimastix patriciarum W5 by transcriptomic and secretomic analyses
Tzi-Yuan Wang, Hsin-Liang Chen, Mei-Yeh J Lu, Yo-Chia Chen, Huang-Mo Sung, Chi-Tang Mao, Hsing-Yi Cho, Huei-Mien Ke, Teh-Yang Hwa, Sz-Kai Ruan, Kuo-Yen Hung, Chih-Kuan Chen, Jeng-Yi Li, Yueh-Chin Wu, Yu-Hsiang Chen, Shao-Pei Chou, Ya-Wen Tsai, Te-Chin Chu, Chun-Chieh A Shih, Wen-Hsiung Li, Ming-Che Shih
Biotechnology for Biofuels , 2011, DOI: 10.1186/1754-6834-4-24
Abstract: We have developed an efficient platform that uses a combination of transcriptomic and proteomic approaches to N. patriciarum to accelerate gene identification, enzyme classification and application in rice straw degradation. By conducting complementary studies of transcriptome (Roche 454 GS and Illumina GA IIx) and secretome (ESI-Trap LC-MS/MS), we identified 219 putative GH contigs and classified them into 25 GH families. The secretome analysis identified four major enzymes involved in rice straw degradation: β-glucosidase, endo-1,4-β-xylanase, xylanase B and Cel48A exoglucanase. From the sequences of assembled contigs, we cloned 19 putative cellulase genes, including the GH1, GH3, GH5, GH6, GH9, GH18, GH43 and GH48 gene families, which were highly expressed in N. patriciarum cultures grown on different feedstocks.These GH genes were expressed in Pichia pastoris and/or Saccharomyces cerevisiae for functional characterization. At least five novel cellulases displayed cellulytic activity for glucose production. One β-glucosidase (W5-16143) and one exocellulase (W5-CAT26) showed strong activities and could potentially be developed into commercial enzymes.Cellulosic ethanol produced by microbial fermentation from feedstocks has been proposed to replace fossil fuels in transportation. A key step in cellulosic ethanol production is to break down cellulose into glucose and hemicellulose into xylose, which can subsequently be converted into ethanol by fermentative microbes. Therefore, finding efficient cellulases is important to bioethanol production, as well as for hydrolyzing feedstocks into sugars in general. Neocallimastix species is one of the major anaerobic fungi in the rumen of water buffalo capable of efficiently digesting cellulosic biomass [1-4]. Such anaerobic fungi are potential sources for highly active cellulolytic enzymes that are useful for cellulose hydrolysis [5-7]. Plant cell wall degrading enzymes from rumen fungi such as Neocallimastix patriciarum may
Screening of Anaerobic Fungi and their Medium Modification for Xylanase Production

ZHU Chong-Miao MAO Sheng-Yong SUN Yun-Zhang ZHU Wei-Yun,

微生物学通报 , 2004,
Abstract: Twelve anaerobic fungal strains isolated from rumen and faeces of ruminants were screened for xylanase prodution. Isolate A4 strain identified as Neocallimastix had the highest xylanase activity among all isolates. With rice straw, corn straw , peanut straw and filter paper as fermentation substrates, the activities of xylanase by A4 were14.31 U/mL, 11.39 U/mL, 6.99 U/mL, 13.38 U/mL, respectively. The effect of cell-free rumen fluid and yeast extract on xylanase production was tested. The results showed that the concentration level of cell-free rumen fluid had no significant effect on xylanase production. However as yeast extract concentration decreased from 1.0 g/L to 0,5 g/L , the enzyme activity decreased significantly ( P < 0.05) .
Detection and diversity analysis of rumen methanogens in the co-cultures with anaerobic fungi

CHENG Yan-fen,MAO Sheng-yong,PEI Cai-xia,LIU Jian-xin,ZHU Wei-yun,

微生物学报 , 2006,
Abstract: Rumen methanogen diversity in the co-cultures with anaerobic fungi from goat rumen was analyzed. Mix-cultures of anaerobic fungi and methanogens were obtained from goat rumen using anaerobic fungal medium and the addition of penicillin and streptomycin and then subcultured 62 times by transferring cultures every 3 - 4d. Total DNA from the original rumen fluid and subcultured fungal cultures was used for PCR/DGGE and RFLP analysis. 16S rDNA of clones corresponding to representative OTUs were sequenced. Results showed that the diversity index (Shannon index) of the methanogens generated from DGGE profiles reduced from 1.32 to 0.99 from rumen fluid to fungal culture after 45 subculturing, with the lowest similarity of DGGE profiles at 34.7%. The Shannon index increased from 0.99 to 1.15 from the fungal culture after 45 subculturing to that after 62 subculturing, with the lowest similarity at 89.2% . A total of 5 OTUs were obtained from 69. clones using RFLP analysis and six clones representing the 5 OTUs respectively were sequenced. Of the 5 OTUs, three had their cloned 16S rDNA sequences most closely related to uncultured archaeal symbiont PA202 with the same similarity of 95 %, but had not closely related to any identified culturable methanogen. The rest two OTUs had their cloned 16S rDNA sequences sharing the same closest relative, uncultured rumen methanogen 956, with the same similarity of 97% .Their 16S rDNA sequences of these two OTUs also showed 97% similar to the closest identified culturable methanogen Methanobrevibacter sp. NT7. In conclusion, diverse yet unidentified rumen methanogen species exist in the co-cultures with anaerobic fungi isolated from the goat rumen.
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