September 2015

Genetic variability of indigenous cowpea genotypes as determined using inter-simple sequence repeats markers

Cowpea [Vigna unguiculata (L.) Walp.] is cultivated widely by small farmers in the semiarid region of Northeastern Brazil for subsistence purposes, especially to complement the family income. However, owing to the limited availability of water in this region, there is an urgent need for novel highly productive drought-tolerant cultivars. The aim of the present study was to establish the genetic variability of 14 cowpea...

Author(s): R. F. M. Mendes, F. B. Britto, F. R. Freire Filho and P. S. C. Lima

September 2015

Essential oil composition of different fractions of Piper guineense Schumach. et Thonn from Cameroon using gas chromatography-mass spectrometry and their insecticidal effect on Sitophilus oryzae (L.)

Essential oil fractions from dried seed powder of Piper guineense were analyzed by gas chromatography-mass spectrometry (GC-MS) and evaluated for their insecticidal effects on Sitophilus oryzae L. The GC-MS analysis showed quantitative and qualitative differences between the oil fractions. Chromatographic results revealed chemical constituents like eugenol, piperanol, pinene, carene, copaene with insecticidal...

Author(s): Esther Obi Oben⊃, Robyn McConchie⊃, Kim Phan-Thien⊃ and Nelson Neba Ntonifor⊃

September 2015

Heritability of polyphenols, anthocyanins and antioxidant capacity of Cameroonian cocoa (Theobroma cacao L.) beans

This study investigates the heritability of polyphenolic, anthocyanin and antioxidant capacity of beans derived from four cocoa clones and their offsprings. These compounds were analyzed at 280 nm (polyphenols) and 520 nm (anthocyanins) by reversed-phase high-performance liquid chromatography (RP-HPLC) method using a photodiode array detector (PDA). The antioxidant capacity of methanolic extracts prepared from cocoa...

Author(s): Pierre Effa Onomo, Nicolas Niemenak, Pierre François Djocgoue, Martine Louise Ondobo and Denis Omokolo Ndoumou

September 2015

Preliminary characterization of residual biomass from Hibiscus sabdariffa Calyces

Hibiscus sabdariffa calyces are mainly used for different agro-food and beverages applications. The residual biomass generated contains various useful substances that were extracted and characterized. It contained 23% (w/w) soluble pectic material, a food additive, extracted with hot acidified water (80°C, pH = 1.5) and precipitated with ethanol. The molecular weight (28.5 and 109.7 kDa), the degree of methylation...

Author(s): Cheikh Beye, , Mario Aguedo, Serge Hiligsmann, Lat Souk Tounkara, Aurore Richel and Philippe Thonart

September 2015

A study of the optimal conditions for glucoamylases obtained from Aspergillus niger using amylopectin from cassava starch as carbon source

A fourteen day pilot study carried out showed that high glucoamylase activities were obtained on the 4 and 11th day of fermentation and the enzymes were harvested on the respective days giving the codes GluAgCSV4 and GluAgCSV11. The optimal pH and optimal temperatures for enzyme activities GluAgCSV4 and GluAgCSV11 were in a range of 6 to 7 and 50 to 55, using cassava, guinea corn and tiger nut starch as substrates,...

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