ISSN 2736-1756
Research Article
Advanced Journal of Microbiology Research Vol. 2016
Available online at http://internationalscholarsjournals.org/journal/ajmr
© 2016 International Scholars Journals
Full Length Research Paper
Comparison of cell growth and ethanol productivity on different pretreatment of rice straw hemicellulose hydrolysate by using Candida shehatae CICC 1766
Wan-Li Sun1,2 and Wei-Yi Tao1*
1Key Lab of Industrial Biotechnology, Ministry of Education, Jiangnan University, Wuxi 214122, China.
2College of Chemistry and Bioengineering, Yichun University, Yichun, China.
Accepted 10 May, 2015
Abstract
In this work, the cell growth and ethanol productivity was tested for lignocellulosic biomass sugars of overliming-detoxified and NaOH-neutralized rice straw acid hydrolysate by using Candida shehatae CICC 1766. When the acetic acid reached 3 g/L in defined xylose medium, the final ethanol concentration was 33% of that in the medium without acetic acid addition. C. shehatae CICC 1766 could bear lower pH (ethanol yield 13.5 g/L at pH 4.0) in overliming-detoxified hydrolysate. At the optimal pH 5.0 the ethanol yield attended to 16.1 g/L. Ethanol yield in NaOH-neutralized hydrolysate was 13.7 g/L which is better than in overliming-detoxified hydrolysate (7.0 g/L) . It suggested that NaOH-neutralized hydrolysate could be directly fermented by using C shehatae CICC 1766.
Key words: Rice straw, Candida shehatae, hemicellulose hydrolysate, ethanol fermentation.
Wei-Yi Tao, Wan-Li Sun
Page: 1 - 10
Research Article
Advanced Journal of Microbiology Research Vol. 2016
Available online at http://internationalscholarsjournals.org/journal/ajmr
© 2016 International Scholars Journals
Full Length Research Paper
In vitro activity of Thaumatococcus daniellii and Megaphrynium macrostachyum against spoilage fungi of white bread and ‘Eba’, an indigenous staple food in Southern Nigeria
Grillo Joseph Adebayo1* and Lawal Adekunle Kolawole2
1Department of Microbiology, Lagos State University, Ojo, P. M. B. 001, Ojo, Lagos State, Nigeria.
2Biotechnology Laboratory, Federal Institute of Industrial Research, Oshodi, P. M. B. 21023, Ikeja, Lagos State, Nigeria.
Accepted 23 March, 2016
Abstract
Fresh white bread and ‘eba’ (a carbohydrate; > 80% starch, indigenous staple food in southern Nigeria) were purchased from traders in Lagos, Nigeria and stored under aseptic conditions in the laboratory at room temperature (27 ± 2°C) (11 h of darkness and 15 h of daylight) for duration of 144 h, during which samples were analyzed at 48 h intervals for fungal population using the plate count technique. The sensitivity of the spoilage fungi to aqueous and methanol extracts of leaves of Thaumatococcus danielli and Megaphrynium macrostachyum was determined using the broth dilution method. Fungal populations increased with hour of storage. For bread, Penicillium sp was dominant throughout with average populations of 2.0 x 101 and 8.01 x 106 cfu/g at 0 and 144 h, respectively, while Mucor sp was dominant in eba with average populations of 1.0 x 101 and 9.5 x 106 cfu/g at 0 and 96 h, respectively. For T. danielli, while the methanol extract had greater activity against the spoilage fungi than the aqueous extract, the reverse was observed for M. macrostachyum. The lowest minimum inhibitory concentration (MIC) of T. danielli was 25 mg/ml of the methanol extract against Saccharomyces cerevisiae and Saccharomyces chevalieri and its lowest minimum cidal concentration (MCC) was 50 mg/ml of the methanol extract against S. cerevisiae and Penicillium sp. For M. macrostachyum, the lowest MIC and MCC were 25 and 50 mg/ml of the aqueous extract respectively against S. chevalieri. The results highlight the potential of extracts of T. daniellii and M. macrostachyum as sources of alternative natural preservatives of bread and ‘eba’.
Key words: Thaumatococcus danielli, Megaphrynium macrostachyum, minimum inhibitory concentration, minimum cidal concentration.
Lawal Adekunle Kolawole, Grillo Joseph Adebayo*
Page: 1 - 10
Research Article
Advanced Journal of Microbiology Research Vol. 2016
Available online at http://internationalscholarsjournals.org/journal/ajmr
© 2016 International Scholars Journals
Full Length Research Paper
Genetic diversity of Fusarium oxysporum f. sp. cubense isolates from Malaysia
S. K. Leong, Z. Latiffah* and S. Baharuddin
School of Biological Sciences, Universiti Sains Malaysia, 11800 Minden, Pulau Pinang, Malaysia.
Accepted 2 April, 2016
Abstract
Genetic diversity of Fusarium oxysporum f. sp. cubense (FOC) isolates were analyzed using enterobacterial repetitive intergenic consensus PCR (ERIC-PCR), random amplified microsatellites (RAMS) and restriction fragment length polymorphism of Intergenic Spacer (RFLP-IGS) . The three molecular techniques showed intraspecific variations and the banding patterns generated using each technique were highly variable. UPGMA cluster analysis of the combined data of the three techniques showed 35.7 - 100% genetic similarity among the FOC isolates. Based on the dendrogram, most of the isolates including four isolates from Indonesia were clustered together in two main clusters. Sequence analysis of TEF-1 gene of some of the isolates of FOC using parsimony and distance methods also showed intraspecific variations. The highly variable banding patterns shown by using molecular methods supported the hypothesis that the isolates of FOC co-evolved with the edible bananas and dissemination of the pathogen was probably through infected rhizomes.
Key words: Fusarium oxysporum f.sp. cubense, enterobacterial repetitive intergenic consensus PCR, random amplified microsatellites, restriction fragment length polymorphism of Intergenic Spacer.
S. K. Leong, Z. Latiffah* and S. Baharuddin
Page: 1 - 10
Research Article
Advanced Journal of Microbiology Research Vol. 2016
Available online at http://internationalscholarsjournals.org/journal/ajmr
© 2016 International Scholars Journals
Full Length Research Paper
Isolation and characterisation of new spore-forming lactic acid bacteria with prospects of use in food fermentations and probiotic preparations
Ali Bayane1*, Bréhima Diawara2, Robin Dauphin Dubois3, Jacqueline Destain3, Dominique Roblain3 and Philippe Thonart3
1 Biotechnology Research Institute, National Council of Research Canada, 6100 Royalmount, Montréal, Québec H4P 2R2 Canada.
2Département de Technologie Alimentaire, IRSAT/CNRST. 03 BP 7047 Ouagadougou 03 Burkina Faso.
3FUSAGx, Unité de Bio-industrie, Centre Wallon de Biologie Industrielle (CWBI), Passage des Déportés 2, 5030 Gembloux, Belgique.
Accepted 25 January, 2016
Abstract
Five spore-forming bacteria producer of lactic acid were isolated from soils sampled in the vicinity of poultry farms in Burkina Faso. All isolates were Gram-positive, motile, mesophilic, facultative anaerobic, catalase positive rods, and with L(+) lactic acid production. The isolates have been characterized and identified by a polyphasic approach, combining various phenotypic and genetic characteristics. The 16S-rDNA-sequence analyses revealed the membership of two isolates to the genus Bacillus and the three other to the genus Paenibacillus. The physiological and biochemical analyses showed that the isolates were quite different from known spore forming lactic acid bacteria. Several relevant technological properties were observed, particularly the resistance of the isolates to bile salts and acidic conditions, even the productions of amylolytic and proteolytic enzymes, which could make them good candidates for certain technological applications such as food fermentations and probiotic formulations. Furthermore, the isolation of these microorganisms in the vicinity of farms reinforces the feasibility of their involvement in animal feedstuffs preparations. In conclusion, this work shows an important diversity within the spore-forming lactic acid bacteria and confirms the conclusions of previous works, which have already shown that the SFLAB (Spore Forming Lactic Acid Bacteria) were good candidates for food fermentation and the probiotic formulations.
Key words: Lactic acid, spore-forming bacteria, biodiversity, bacillus, 16S rDNA.
Dominique Roblain and Philippe Thonart, Bréhima Diawara, Ali Bayane*, Jacqueline Destain, Robin Dauphin Dubois
Page: 1 - 10
Research Article
Advanced Journal of Microbiology Research Vol. 2016
Available online at http://internationalscholarsjournals.org/journal/ajmr
© 2016 International Scholars Journals
Full Length Research Paper
Antifungal activities of neem (Azadirachta indica) seed kernel extracts on postharvest diseases in fruits
Jingfa Wang, Jian Li, Jiankang Cao and Weibo Jiang*
College of Food Science and Nutritional Engineering, China Agricultural University, P.O. Box 608, Qinghua Donglu No. 17, Beijing, 100083, China.
Accepted 17th May, 2016
Abstract
To learn the antifungal effects of neem seed kernel extract (NE) on the post harvest diseases, pathogens of Monilinia fructicola, Penicillium expansum, Trichothecium roseum and Alternaria alternate isolated from the infected fruit were treated with NE in vitro. Results showed that growth of the four pathogens could be significantly (P < 0.05) reduced by NE. The diseases in fruit of plum (Prunus salicina) or Yali pear (Pyrus bertschneideri) inoculated with the pathogens could be prevented remarkably by treated fruit with NE.
Key words: Neem seed kernel extracts, antifungal, fruits, post harvest, pathogens.
Jian Li, Jingfa Wang, Jiankang Cao and Weibo Jiang*
Page: 1 - 10
Research Article
Advanced Journal of Microbiology Research Vol. 2016
Available online at http://internationalscholarsjournals.org/journal/ajmr
© 2016 International Scholars Journals
Full length Research Paper
Differentiation of Salmonella enterica based on PCR detection of selected somatic and flagellar antigens
Mohd Elbagir Elhassan Nori and Kwai Lin Thong*
Institute of Biological Sciences, Faculty of Science, University of Malaya, 50603, Kuala Lumpur, Malaysia.
Accepted 22 April, 2015
Abstract
Serotyping is the basis of Salmonella surveillance. However, the limitations of the traditional serotyping have stimulated rapid research and development in DNA-based serotyping. The aim of this study was to apply a combination of sequential multiplex PCRs targeting the O, H and Vi antigens to serotype a panel of 122 recently isolated human- and foodborne- Salmonella strains. The mPCR that targets the o (genes wzxC2, rfbJ, prt, tyv, wzxE, wzxC1, prt) and Vi (viaB) antigens successfully subtyped the strains into serogroups C2 (n = 35, 28.7%), B (n = 33, 27.1%), D9 (n = 29, 22.9%), E (n = 21, 17.2%), C1 (n = 2, 64%) and A (n = 2, 1.64%). Eight of the Salmonella strains from serogroup D were positive for Vi antigen. Two multiplex PCRs were optimized for detection of H1 antigens (Ha, Hb, Hd, r, z10, z6, g and m) and H2 antigens (1.5, 1.2, 1.6 and enx). Overall, the multiplex PCRs of O, H and Vi antigens results correctly serotyped 94 of 122 strains (77%). The most frequent serovars encountered were Salmonella weltevrerden, Salmonella enteritidis, Salmonella typhimurium, Salmonella hadar and Salmonella typhi. Application of DNA based technique for serogrouping and serotyping of the selected Salmonella enterica was found to be robust, quick, specific and reliable for the specific antigenic targets and is useful in the study area which lack complete serotyping facilities.
Key words: Salmonella, somatic antigens (O), flagella antigens (H), serotyping, multiplex PCR.
Kwai Lin Thong*, Mohd Elbagir Elhassan Nori
Page: 1 - 10