African Journal of

  • Abbreviation: Afr. J. Biotechnol.
  • Language: English
  • ISSN: 1684-5315
  • DOI: 10.5897/AJB
  • Start Year: 2002
  • Published Articles: 12485

Table of Content: 25 May, 2016; 15(21)

May 2016

Effect of cadmium on the morphology and anatomy of Salvinia auriculata

This study aimed to evaluate the morphological and anatomical changes of Salvinia auriculata exposed to different concentrations 0, 2.5, 5, 7.5 and 10 µM of cadmium (Cd)  and its effect on plant growth. The experiment was conducted in the laboratory of Plant Anatomy of the IF Goiano/Rio Verde Campus, Goiás. Cd free samples of S. auriculata, was obtained from the Aquários Plantados company,...

Author(s): Rodrigues, D. A., Vasconcelos Filho, S. C, Rodrigues, A. A., Rampazzo, D. F., Rodrigues, C. L., Vasconcelos, J. M. and Magalhães, P. A. N. R.

May 2016

Surface composition and surface properties of water hyacinth (Eichhornia crassipes) root biomass: Effect of mineral acid and organic solvent treatment

The surface composition and surface properties of water hyacinth (Eichhornia crassipes) root biomass were studied before and after extraction with dilute nitric acid and toluene/ethanol (2/1, v/v) followed by ethanol, using Fourier Transform Infra-red (FT-IR) spectroscopy, thermogravimetric analysis, x-ray diffraction, scanning electron microscopy. FT-IR absorption bands were obtained at 3421, 2855, 1457 and 1035 cm-1...

Author(s): Netai Mukaratirwa-Muchanyereyi, , Jameson Kugara and Mark Fungayi Zaranyika

May 2016

In-silico smart library design to engineer a xylose-tolerant hexokinase variant

Saccharomyces cerevisiae has two hexokinases ScHxk1 and ScHxk2 that catalyze ATP-dependent phosphorylation of glucose and other hexoses. ScHxk2 plays an important role in glucose metabolism and the process of bioethanol production. The presence of xylose in the fermentation medium was found to inhibit ScHxk2. Therefore development of ScHxk2 variants that are resistant to the action of xylose is needed. In the current...

Author(s): Yasser Gaber

May 2016

Morphological diversity in oleaginous watermelon (Citrullus mucosospermus) from the Nangui Abrogoua University germplasm collection

A hundred and seventy-one oleaginous watermelon accessions either collected from different countries or obtained from gene banks were evaluated and compared based on 11 quantitative morphological traits. Principal component analysis on 11 traits revealed 81.19% of the total variability and pointed out variations among accessions, mainly on the basis of fruit size and weight. The dendrogram and factorial discriminant...

Author(s): Ahou A. Gbotto, Kouamé K. Koffi, Nandy D. Fouha Bi, Serge T. Doubi Bi, Hippolyte H. Tro, Jean-Pierre Baudoin and Irié A. Zoro Bi

May 2016

Impact of transgenic cotton expressing cry1Ac and cry2Ab genes on soil rhizosphere bacterial and fungal populations in soils of central Kenya

The impact of 9 months cultivation of transgenic Bacillus thuringiensis (Bt) cotton on selected culturable bacterial and fungal populations in rhizosphere soil was investigated. The transgenic Bt cotton line (06Z604M), isoline (99M03) and a non-Bt cotton line (HART 89M) were planted in confined field site in Samuru-Thika where non-Bt cotton had been continuously cultivated for the past 2 years. Rhizosphere...

Author(s): J. Swilla, C. N. Waturu and S. T. Rubindamayugi

May 2016

Expression and purification of recombinant Shiga toxin 2B from Escherichia coli O157:H7

Enterohemorrhagic Escherichia coli are important human food-borne pathogens. Recently, Shiga toxin-producing E. coli (STEC) causes life-threatening hemolytic-uremic syndrome (HUS). In this study, Stx2B gene, a subunit of Shiga toxin, was amplified via polymerase chain reaction (PCR) from the chromosomal DNA of clinical fecal sample using appropriate primers. The PCR product was cloned to commercially available plasmid...

Author(s): Marwa E. A. Aly,  Amro S. Hanora, Tamer M. Essam and Magdy A. Amin

May 2016

Genetic characterization by amplified fragment length polymorphism (AFLP) markers and morphochemical traits of Carica papaya L. genotypes

Carica papaya L. is a native fruit from Central America and Mexico and it is an economically important fruit. As a pre-breeding genetic study, the variability of both parents (L7 and M22) and the F1 individuals derived from their crosses (L7 × M22), was evaluated in terms of 32 morphochemical traits, and contrasted with their genetic diversity indicated by amplified fragment length polymorphism (AFLP) markers....

Author(s): Mariela Vázquez Calderón, Javier O. Mijangos-Cortés, Manuel J. Zavala L., L. Felipe Sánchez Teyer, Adriana Quiroz M., Matilde Margarita Ortiz G., Fernando Amilcar Contreras M., Francisco Espadas G., Gabriela Fuentes Ortiz and Jorge M. Santamaría

May 2016

Assessment of genetic diversity among sixty bread wheat (Triticum aestivum) cultivars using microsatellite markers

Assessment of genetic diversity among wheat cultivars is important to ensure that a continuous pool of cultivars with varying desirable traits is maintained. In view of this, a molecular study was conducted to assess the genetic diversity of sixty wheat cultivars using sixty microsatellite markers. Amplified alleles from each cultivar were scored after running in 6% poly acrylamide gel electrophoresis (PAGE). A...

Author(s): Vincent Mgoli Mwale, Xiuli Tang and Eric Chilembwe

May 2016

Fermentative intensity of L-lactic acid production using self-immobilized pelletized Rhizopus oryzae

L-Lactic acid is a promising three-carbon building-block chemical, widely used in the food, pharmaceutical, leather and textile industries and Rhizopus oryzae is an important filamentous fungus for the production of L-lactic acid with high optical purity. This study investigated the medium compositions for the maximum biomass cultivation of R. oryzae L-lactic acid fermentation, and optimized the operation parameters for...

Author(s): Shuizhong Luo, Xuefeng Wu, Yu Zhu, Xingjiang Li, Shaotong Jiang and Zhi Zheng

May 2016

Effect of pH, various divalent metal ion and different substrates on glucoamylase activity obtained from Aspergillus niger using amylopectin from tiger nut starch as carbon source

Glucoamylases were obtained from Aspergillus niger using amylopectin from tiger nut starch as carbon source on the 5th (GluAgTN5) and 12th day (GluAgTN12) of fermentation. The optimal pH for GluAgTN5 at 55°C were 6.5, 7.0, 6.0 while that for GluAgTN12 were 8.5, 6.0, 7.5 at 50°C using cassava, guinea corn and tiger nut starch as substrates, respectively. The enzyme activity in GluAgTN5 was enhanced by Ca2+ and...

Author(s): Ezugwu A. L., Ottah, V. E., Eze, S. O. O. and Chilaka F. C.

May 2016

Trials to improve the response of Orechromis niloticus to Aeromonas hydrophila vaccine using immunostimulants (garlic, Echinacea) and probiotics (Organic GreenTM and Vet-YeastTM)

This work aimed to investigate the role of some immunostimulants and probiotics in improving the response of overwintered tilapia to Aeromonas hydrophila vaccine. In this study, 15000 Nile tilapia fry (Orechromis niloticus) were collected and divided into five groups. Group 1 was the control, groups 2 to 5 were fed diet supplemented with garlic, Echinacea, Organic GreenTM and Vet-YeastTM respectively for 5 months....

Author(s): Salah Mesalhy Aly, Mohamed A. Al Zohairy, Arshad H. Rahmani, Mohamed Fathi and Nashwa M. Abdel Atti