African Journal of
Biotechnology

  • Abbreviation: Afr. J. Biotechnol.
  • Language: English
  • ISSN: 1684-5315
  • DOI: 10.5897/AJB
  • Start Year: 2002
  • Published Articles: 12497

Table of Content: 12 June 2012; 11(47)

June 2012

Modeling of nitrogen removal and control strategy in continuous-flow-intermittent-aeration process

The continuous-flow-intermittent-aeration process was introduced to achieve nitrogen removal in a wastewater treatment plant (WWTP). Without structural readjustment of completed mixed activated-sludge treatment unit, operation scheme of intermittent aeration would be upgraded to promote the WWTP performance. As an aid of the implementation, mathematical simulation models were developed as an invaluable tool. Due to some...

Author(s): Tian-yin HUANG, Ning LI and Yong HUANG

June 2012

Partial immunity in murine by immunization with a toxoplasmic DNA vaccine

Toxoplasma gondii is an obligate intracellular protozoan that is causative agent of atoxoplasmosis, a disease which may result in a spectrum of consequences. Previous studies have reported that DNA vaccine can be effective in partial protection against this parasite. In this study, we constructed a single DNA vaccine containing rhoptry protein 1 (ROP1) and evaluated its immune response in Balb/c mice. We used alum...

Author(s): Z. Eslamirad, A. Dalimi, F. Ghaffarifar, Z. Sharifi and S. Ghasemi Nikoo

June 2012

Isolation and characterization of an Aux/IAA gene (LaIAA2) from Larix

The phytohormone auxin controls many aspects of plant development. Auxin/indole-3-acetic acid (Aux/IAA) transcriptional factors are key regulators of auxin responses in plants. To investigate the effects of auxin on gene expression during the rooting process of Larix cuttings, a subtractive cDNA library was constructed and 272 UniEST were obtained by using suppression subtractive hybridization (SSH). Based on...

Author(s): Jian Feng, Liwang Qi, Xiaomei Sun, Yongqi Lin, Jian Dong and Shougong Zhang

June 2012

Genetic diversity of rose germplasm in Pakistan characterized by random amplified polymorphic DNA (RAPD) markers

Random amplified polymorphic DNA (RAPD) markers have been found to be very useful in studying the genetic variability of different species, including Rosa. Present studies were undertaken for the identification and analysis of genetic variation within a collection of 4 species and 30 accessions of rose using RAPD analysis technique. The results showed the molecular distinctions among the genotypes when analysed...

Author(s): Saadia Azeem, Azeem Iqbal Khan, Faisal Saeed Awan, Atif Riaz and Sultan Bahadur

June 2012

Calpastatin (CAST) gene polymorphism in Kajli, Lohi and Thalli sheep breeds

Calpastatin-encoding gene (CAST) is located on the fifth chromosome of sheep and it plays an important role in the development of muscles and in meat tenderness. The present study was conducted to investigate a calpastatin (CAST) gene polymorphism in Pakistani Thalli, Lohi and Kajli sheep breed. Random blood samples were collected from 300 animals (100 samples from each Thalli, Lohi and Kajli...

Author(s): Muhammad Suleman, Saeed U. Khan, M. Naeem Riaz, Muhammad Yousaf, Abdullah. Shah, Rafaqat Ishaq and Abdul ghafoor

June 2012

Effect of small mapping population sizes on reliability of quantitative trait locus (QTL) mapping

A limitation of quantitative trait loci (QTL) mapping is that accuracy of determining QTL position and effects are largely determined by population size. Despite the importance of this concept, known as the "Beavis effect there has generally been a lack of understanding by molecular geneticists and breeders. One possible explanation for this may be that this concept has been explored by using computer...

Author(s): C. Raghavan and B. C. Y. Collard

June 2012

Response surface methodology analysis to improve production of tyrothricin in Bacillus brevis

Sequences of experimental designs were applied to optimize medium and fermentation conditions in order to enhance the tyrothricin production by Bacillus brevis (ATCC 8185). A significant influence of casein peptone, NaCl and yeast extract on tyrothricin yield was evaluated by Plackett–Burman (PB) design. The optimal concentration range of the three factors was examined by the steepest ascent method and...

Author(s): Yuguang Zhang, Lu Jiang, Fazheng Ren, Jiping Yang, and Huiyuan Guo,

June 2012

Correlation between morphological characters and estimated bunch weight of the Tropical banana cultivar

The objective of this study was to measure and identify the variables that have more influence on bunch weight (BW), and determine a statistical model for predicting yield for the Tropical banana cultivar (cv.). The experiment consisted of a uniformity trial, conducted in Guanambi, Bahia, with a total of 360 plants of the Tropical cultivar YB42-21 (AAAB) in an...

Author(s): Joyce Dória Rodrigues Soares, Moacir Pasqual, Filipe Almendagna Rodrigues, Willian Soares Lacerda, Sergio Luiz Rodrigues Donato, Sebastião de Oliveira e Silva and Crysttian Arantes Paixão

June 2012

Social and economic factors for the adoption of biological control of Bracon parasitoid on corn Caradrina in Dezful Township, Khouzestan Province, Iran

The purpose of this study was to analyze the social and economic factors involved in the adoption of the biological control of Bracon parasitoid on corn Caradrina in Dezful Township, Khouzestan province, Iran. The method of research was causal comparative. A random sample of corn farmers from Dezful Township of Khouzestan province, Iran (n=350) was selected for participation in this...

Author(s): Ahmad Reza Ommani and Azadeh N.Noorivandi

June 2012

Nutritional paradigm of vermicompost enhances tolerance to endosulfan in Cicer arietinum

A nutritional factor in vermicompost has been exploited suitably to stimulate growth of chickpea Cicer arietinum. It was noticed that incorporating 12.5% of vermicompost stimulates the plant in every aspect of growth and development. Germination rate decreased during 10 to 15 days of treatment. However, it becomes identical to the control after 20 days of treatment. The percentage of increase in total...

Author(s): A. K. Sharan, K. Dileep Singh, V. Chandra, G. D. Sharma, Shellu kumari and C. Jee

June 2012

Expression of WRKY and MYB genes during infection with powdery mildew in cucumber (Cucumis sativus L)

The expression change pattern of three transcription genes (WRKY30, WRKY6 andMYB) in two cucumber lines with different powdery mildew resistance (resistant line ‘JIN5-508’ and susceptible line ‘D8’) were investigated during the infection process with powdery mildew using real-time quantitative polymerase chain reaction (RT-PCR). Gene expression analysis during different time points revealed...

Author(s): Mouammar Alfandi, Jing-jing Luo, Xiao-hua Qi, Qiang Xu and Xue-hao Chen

June 2012

Allelopathic potential of Arctotis arctotoides (L.f.) O. Hoffm aqueous extracts on the germination and seedling growth of some vegetables

Aqueous shoot and root extracts of Arctotis arctotoides were tested for their allelopathic properties on cabbage, carrot, tomato and spinach seed germination and seedling growth. The addition of the two extracts at 8 and 10 mg ml-1 resulted in the highest germination inhibitions. The shoot extract at 10 mg ml-1 inhibited cabbage, carrot, tomato and spinach seed germination by 79.1, 75.6,...

Author(s): Abimbola Badmus and Anthony Afolayan

June 2012

Heavy metal induced ecophysiological function alterations in the euhalophyte Suaeda salsa

Heavy metal accumulation affects the physiological status of plants. Suaeda salsa L. is used to investigate the toxic effects of cadmium (Cd) and lead (Pb) either alone or mixtures under the static test conditions. Cd-Pb mixture exposure can decrease lignin content and weaken the increase. Mitochondrial calcium content significantly reduced at 30 μM Cd and Pb exposure. Cd-Pb mixture exposure can increase...

Author(s): Zhaoxiang HAN,, Jiaying LI, Dandan WU and Chunxia LÜ

June 2012

Inoculation effects of two South African cyanobacteria strains on aggregate stability of a silt loam soil

Two South African cyanobacteria strains (coded 3g and 7e) of the genus Nostoc were evaluated for improvement of the aggregate stability of a silty loam soil with low organic C content and compared with Nostoc strain 9v isolated from a Tanzanian soil. The soil was either cropped with maize or non-cropped and inoculated with the three strains in a glasshouse. After 42 days, the aggregate stability...

Author(s): Mfundo P. Maqubela, Pardon Muchaonyerwa and Pearson N.S. Mnkeni

June 2012

Production and partial characterization of invertase from Mucor geophillus EFRL 03

In the present study, cultural conditions for invertase production from Mucor geophillus using Brassica niger (oilcake) in batch wise submerged fermentation was investigated. The effects of time period (24 to 240 h), carbon sources [Brassicacampestris, B. niger, pomegranate peel, coconut, malta peel, apple pulp and glucose (control)] and nitrogen sources (peptone, yeast extract, corn steep...

Author(s): Abdul Sattar Qureshi, Imrana Khushk, Muhammad Aqeel Bhutto, Muhammad Umar Dahot, Ikram-ul-Haq, Safia Bano and Humera Iqbal

June 2012

Cloning of neuraminidase (NA) gene and identification of its antiviral activity

Neuraminidase not only works as an antigen, inducing target-specific antibodies, but also plays a role of enzyme activity and destroys the sialic acid receptor required by virus infection of the host cell surface which protects the host from virus damage. In order to explore a new idea to use neuraminidase (NA) gene and produce disease-resistant transgenic poultry, prokaryotic expression vector pGEX-NA was constructed...

Author(s): Yani Zhang, Liwei Ren, Wei Li, Qi Xu, Guobin Chang, Xiaoyan Wang and Bichun Li  

June 2012

Gas chromatography-mass spectrometry (GC-MS) analysis and in vitro evaluation of antioxidant and antimicrobial activities of various solvent extracts from Citrullus colocynthis (L.) roots to control pathogen and spoilage bacteria

Citrullus colocynthis (L.) schrad is an important medicinal plant belonging to the family of Cucurbitaceae. In the present study we evaluated in vitro the antimicrobial and the antioxidant properties of various solvent extracts from C. colocynthis roots as well as the latter phytochemical characterisation. Total phenolic and flavonoid contents were determined. The highest content of total...

Author(s): Anis Ben HSOUNA, and Abdullah Sulaimain ALAYED

June 2012

Changes in the protein profile of Habanero pepper (Capsicum chinense J.) somatic embryos during development

Protein profile was studied during the development of Capsicum chinense somatic embryos. The total protein content and profile of polypeptides (by sodium dodecyl sulfate polyacrylamide gel electrophoresis) of somatic embryos at different developmental stages (globular, heart-shaped, torpedo and cotyledonary stages) were analyzed. The protein profile of zygotic embryos included nine exclusive bands with...

Author(s): Carlos A. Lecona-Guzmán, Daniela Solís-Marroquín, Susana Aviles-Viñas, César De los Santos-Briones and Nancy Santana-Buzzy

June 2012

Overcoming heat shock protein inhibition at critical temperature vital for survival in Solanum tuberosum L. in vivo condition

Heat stress proteins (HSPs) and related cognates are candidates mediating and preventing cellular damage from heat-stress, but their expression can be inhibited midway. The time-based occurrence pattern for heat mediated inhibition underlying HSPs expression at 41.5°C and revival subsequent stress was studied in vivo for fourSolanum tuberosum L. cultivars viz. Kufri Pukhraj, Kufri...

Author(s): Bengyella Louis, Pranab Roy, Tamgue Ousman, Sayanika Waikhom Deviand Narayan Chandra Talukdar

June 2012

11 β-Hydroxylation of cortexolone using immobilized Cunninghamella elegans protoplasts

Transformation of cortexolone to cortisol and prednisolone by the filamentous fungusCunninghamella elegans protoplasts as a research tool was studied. The immobilized protoplasts of the fungus hydroxylated cortexolone at 11-position had significantly higher activity than the free protoplasts. Sucrose as an osmotic stabilizer was found to be best at 0.6 M level. Relatively higher cortexolone bioconversion was...

Author(s): Reda F. Allam, Mona S. Shafei⊃, Abd El-Monem H. El-Refai, Mohamed I. Ali, Abd El-Naser A. Khattab and Sayeda S. Mohamed

June 2012

Prevalence and molecular typing of the antiseptic resistance genes qacA/B among Staphylococcus aureus strains isolated in a teaching hospital

The qacA/B genes are found in Staphylococcus aureus and confer resistance to various antiseptics and disinfectants. Herein, the prevalence of the qacA/B genes in methicillin-resistant S. aureus (MRSA) and methicillin-sensitive S. aureus (MSSA) was investigated. Molecular typing systems were used to analyse the relatedness of these qacA/B-positive strains. 176 six...

Author(s): Xiao Yu Wei, Tao Luo, Bei Jia, Li Jun Chang, Xiao Qiang Li and Wen Xiang Huang

June 2012

Enhancement of plasmid-mediated stable gene expression by woodchuck hepatitis virus post-transcriptional regulatory element (WPRE) in human embryonic kidney (HEK293) cells

Influence of random integration site on the expression of transgene in mammalian cells makes it a major challenge to achieve high productivity of recombinant proteins. Optimization of expression vector is one of the most popular strategies to resolve this problem. Among this, woodchuck hepatitis virus post-transcriptional regulatory element (WPRE) is a possible enhancer of gene expression in mammalian cells that...

Author(s): Lingling Ye, Jian Xu, Shichong Li, Hong Liu, Xingmao Liu, Qiwei Wang and Zhaolie Chen

June 2012

Antibacterial and synergistic effects of Nardostachytis rhizoma extracts on methicillin-resistant Staphylococcus aureus

Methicillin-resistant Staphylococcus aureus (MRSA) is a serious clinical problem worldwide. Few new drugs are available against MRSA, because it has the ability to acquire resistance to most antibiotics which consequently increases the cost of medication. In the present study, the antibacterial activity ofNardostachytis rhizoma was investigated. The most effective method is to develop antibiotics...

Author(s): Dae-Ki Joung, Young-Hwa Kim, Kyung-Hee Lee, Dong-Yeul Kwon, Jang-Gi Choi, Dong-Soo Ha, Dong-Young Shin, Kee-Tae kweon and Dong-Won Shin

June 2012

Correlation analysis of milk production traits across three generations of Simmental cows

The relationship between milk production traits over whole lactations was evaluated across three generations of Simmental cows (between daughters, dams and granddams) by a corelation analysis with whole lactation traits in the daughter generation being used as the dependent variables (x1), and those in the dam and granddam generations being used as the independent variables (x2 and x3). The results were obtained...

Author(s): Petrovic D. Milun, Bogdanovic Vladan, Djedovic Radica, Skalicki Zlatko, Petrovic M. Milan, Bogosavljevic-Boskovic Snezana and Djokovic Radojica