African Journal of Virology Research

Key words: Burukutu, pito, organoleptic properties.

African Journal of Virology Research ISSN 3421-7347 Vol. 5 (4), pp. 001-006, April, 2011. © International Scholars Journals

Full Length Research Paper

Seroprevalence of foot and mouth disease in Bench Maji zone,Southwestern Ethiopia

Esayas Gelaye¹*, Gelagay Ayelet¹, Tsegalem Abera² and Kassahun Asmare²

¹National Veterinary Institute, P. O. Box: 19, Debre zeit, Ethiopia.

²Hawassa University, Faculty of Veterinary Medicine, P. O. Box: 05, Hawassa, Ethiopia.

Accepted 13 January, 2011

Abstract

A cross-sectional sero -epidemological study was conducted in two districts of the Bench Maji Zone, Southwestern Ethiopia between November 2007 and February 2008 with the objective of determining the seroprevalence of Foot and Mouth Disease (FMD) in cattle and identifying the potential risk factors associated with the disease. Sera samples were collected from a total of 273 cattle in 98 herds. The sera were submitted to the National Veterinary Institute (NVI), Debre zeit, Ethiopia for screening using the 3ABC-ELISA. The overall seroprevalence of FMD was 12.08% (n=273) . Significantly higher seroprevalence (20%) was recorded in the Surma district compared to the Semen Bench district (5.88%). Peasant associations (equivalent to villages in a district) had prevalence rates of 25, 20, 15, 8.16, 5.66 and 3.92% for Kibish, Tulgit, Koka, Aman, Mizan and Temenja-yasz respectively. From the various risk factors analyzed peasant associations, cross boundary movement and herd size were seen to be statistically associated (p<0.05) with the seroprevalence of FMD. There was no significant variation in seroprevalence among sex, age and herd type. The result of the present study showed that FMD is an important cattle disease in the study area. Thus, an appropriate control strategy has to be designed and applied which could involve regulation of transboundary cattle movement and vaccination using the circulating virus strain.

Key words: Bench Maji zone, cattle, FMD, risk factors, sero-epidemiology.

African Journal of Virology Research ISSN 3421-7347 Vol. 5 (3), pp. 001-007, March, 2011. © International Scholars Journals

Full Length Research Paper

Production and application of glucose-fructose oxidoreductase for conversion of pineapple juice sugars

M. G. Aziz^1,2*, Y. A. Yusof² and K. D. Kulbe³

¹Department of Food Technology and Rural Industries, Bangladesh Agricultural University, Mymensingh, Bangladesh.

²Department of Process and Food Engineering, Faculty of Engineering, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor DE, Malaysia.

³Division of Food Biotechnology, Department of Food Science and Technology BOKU, University of Natural Resources and Applied Life Sciences, Vienna Muthgasse 20, Austria.

Accepted 12 October, 2010

Abstract

This work is concerned with the production of glucose-fructose oxidoreductase (GFOR) enzyme for converting pineapple juice sugars into dietetic derivatives. GFOR was produced from Zymomonas mobilis by sub-merge fermentation of 10 L. During fermentation, the highest biomass formation was observed at 24 h and the highest enzyme activity per g biomass was observed at 27 h of fermentation. Cells were isolated by centrifugation, broken down by high pressure homogenizer, enzyme separated by centrifugation and finally the enzyme was purified on a dye substituted column. Electrophoresis of separated fractions confirmed its structure showing a band at 40 kD. Application of GFOR successfully converted pineapple juice sugars; fructose and glucose into sorbitol, a low calorie sugar alcohol, and gluconic acid, respectively. This enzyme was found highly efficient in case of converting juice sugars of fruits juices having higher natural pH.

Key words: Glucose-fructose oxidoreductase, fermentation, conversion, pineapple juice sugars.

African Journal of Virology Research ISSN 3421-7347 Vol. 5 (3), pp. 001-007, March, 2011. © International Scholars Journals

Full Length Research Paper

Antibiotic activity of bacterial isolates associated with entomopathogenic nematodes

Huan Wang^1,2, Yan-Qun Liu², Hui Dong³, Li Qin², Bin Cong^3* and Tian-Lai Li^1*

¹College of Horticulture, Shenyang Agricultural University, Shenyang110866, China.

²College of Bioscience and Biotechnology, Shenyang Agricultural University, Shenyang, 110866, China.

³College of Plant Protection, Shenyang Agricultural University, Shenyang, 110866, China.

Accepted 18 November, 2010

Abstract

In the present study, we isolated 23 strains of symbiotic bacteria from 23 entomopathogenic nematodes strains gathered in different vegetation from different regions of China. The antibiotic activities of all these bacteria strains isolated were evaluated in the laboratory. All the bacteria effectively inhibited seven kinds of plant pathogenic fungi (Bipolaris sorokinianum, Fusarium graminearum, Fusarium moniliforme, Cordana musae (zimm.) Hohn, Colletotrichum gloeosporiodies, Alternaria solani and Alternaria alternata (Fries) Keissler) cultured on agar plates. Among these strains, strain SY5 was the most effective symbiotic bacteria strain, which was further selected as the highly virulent bacteria for the adversity resistance study. The adversity resistance showed that the stability of the antibiotic activity against different plant pathogenic fungi was different. The antibiotic activity against A. solani was the most stable and the inhibiting rate was not affected by treatment in a 50°C water bath for 60 min and in 100°C for 10 min, ultraviolet light exposure for 120 min and storing at room temperature for 90 days.

Key words: Entomopathogenic nematode symbiotic bacteria, Inhabiting rate, temperature, ultraviolet light exposure and duration of maintenance.

African Journal of Virology Research ISSN 3421-7347 Vol. 5 (2), pp. 001-009, February, 2011. © International Scholars Journals

Full Length Research Paper

Improve lipid production by pH shifted-strategy in batch culture of Chlorella protothecoides

Guobin Liang¹, Yiwei Mo²*, Jianghong Tang¹ and Quanfan Zhou¹

¹School of Chemistry and Environmental Engineering, Jiangsu Teachers University of Technology, Changzhou 213001, China.

²South Subtropical Crop Research Institute, Chinese Academy of Tropical Agricultural Science, Zhanjiang 524091, China.

Accepted 31 October, 2010

Abstract

Effects of culture broth pH values on cells growth and lipid production were investigated in heterotrophic cultivation of Chlorella protothecoides. Based on the phenomenon that lower pH value favors cells growth but retards lipid synthesis and vice versa for higher pH value, a novel pH-shift strategy, optimized via simulating Gauss function, was developed. By controlling pH at 5.0 for first 93 h and switching to 6.5 afterwards, final lipid yield and productivity reached 3.75 g/L and 20.8 mg/L/h, increased by 24.2 and 38.7%, respectively as compared to constant pH 6.0 operations. Moreover, by feeding glucose and aqueous ammonia replacing sulphuric acid (H₂SO4) and NaOH solutions to control pH, maximal lipid yield of 3.96 g/L was achieved, suggesting application of the novel pH-shift strategy for lipid overproduction as being feasible.

Key words: Heterotrophic cultivation, lipid, ph-shift strategy, glucose and Chlorella protothecoides.

African Journal of Virology Research ISSN 3421-7347 Vol. 5 (2), pp. 001-008, February, 2011. © International Scholars Journals

Full Length Research Paper

Poly-3-hydroxybutyrate production from methanol by Methylosinus trichosporium IMV3011 in the non-sterilized fed-batch fermentation

Hao Song^1,3, Jiaying Xin^1,2, Yingxin Zhang^1,4, Weibao Kong^1,3 and Chungu Xia^1*

¹State Key Laboratory for Oxo Synthesis and Selective Oxidation, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou 730000, China.

²Laboratory for Food Science and Engineering, Harbin University of Commerce, Harbin 150076, China.

³Graduate University of Chinese Academy of Sciences, Beijing 10039, China.

⁴Division of Functional Materials and Nanodevices, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo 315201, China.

Accepted 19 November, 2010 

Abstract

The methanotrophic bacteria have promising applications in the production of a biopolymer, poly-3-hydroxybutyrate (PHB). The fed-batch fermentation strategies were studied for PHB accumulation by methanol-grown Methylosinus trichosporium IMV3011 under the non-sterilized conditions. The biomass of 2.91 g dry wt/L and PHB accumulation of 47.6% (w/w) were reached in the fed-batch fermentation. In order to increase PHB content, some organic acids were added into the culture as inhibitors of tricarboxylic acid cycle (TCA). It was found that the malic acid should be optimum for PHB accumulation. The biomass and PHB yield would increase to 3.32 g dry wt/L and 58.5% (w/w), respectively by adding 0.2 g/L malic acid. Other key intermediates in the metabolism such as citric acid, succinic acid and acetyl-CoA, also influenced the cell growth and PHB accumulation to a certain extent. The PHB produced in the fermentation process was of steady quality with molecular weights up to 1.7 × 10⁶ Da.

Key words: Biosynthesis, poly-3-hydroxybutyrate, methanotrophic bacteria, methanol, fed-batch fermentation.