Cyanogenic Glycoside Content of Fresh and Processed Peels of Four Improved Ghanaian Cassava Cultivars

The cyanogenic glycoside levels of four relatively new Ghanaian cassava cultivars were determined spectrophotometrically. The mean values obtained were 393.8, 548.9, 702.1 and 424.7 p.p.m. for Afisiafi, Abasafitaa, IITA9904 and Tech Bankye, respectively. The effects of sun-drying and a combination of soaking and sun-drying on the cyanogenic glycoside content were investigated. Soaking in water for 24 h followed by sun-drying for 24 h resulted in a 63 –74 per cent reduction in cyanogenic glycoside levels compared with 27 – 64 per cent reduction after sun-drying for 48 h. The results showed a significant reduction in cyanide potential of all the varieties following sun-drying and the combination of soaking and sun-drying (P < 0.05). The combination of soaking and sun-drying was more effective than sun-drying alone

ERRATA:Selected Ghanaian Cassava and Sweet Potato Cultivars: Evaluation of Flour and Wort Quality

Studies were conducted on the suitability of flour samples of three cultivars of cassava (Afisiafi, Gblemoduade, and Tekbankye) and sweetpotato (Sauti, Farah, and TIB2) as brewing adjuncts. Significant varietal differences (

Malting and Brewing Properties of Selected Cereals Cultivated in Ghana

To promote the industrial use of local cereals in Ghana, studies were carried out on the suitability of malts from rice (WITA 1), sorghum (Kapala) and local late millet for the production of beer. The values obtained for mean diastatic power at the end of the malting period were rice (129.1oWK), millet (102.1oWK) and sorghum (84.0oWK). The saccharification time for each of the flour samples was less than 15 min using barley malt of diastatic power 340oWK. Significant differences (

A Simple Procedure for the Isolation of Laccase from the Growth Substrate of Pleurotus oestreatus

Extracellular laccase was isolated from the residual substrate of Pleurotus oestreatus (oyster mushroom), without the addition of aromatic inducers, in order to investigate its potential as an effective tool for the biochemical transformation of lignified and polyphenol-containing crop residues. The crude enzyme was purified by subjecting samples to ammonium sulphate precipitation, gel filtration chromatography using Sephadex G-75, and anion exchange chromatography on DEAE-cellulose. The laccase was purified to electrophoretic homogeneity and it exhibited chemical characteristics similar to those of laccases in other studies. The purified laccase was estimated to have a molecular mass of 78 kDa. The laccase oxidized dimethoxyphenol optimally at pH 5.0 and significantly over a wide pH range (4.5 to 8) and showed maximum laccase activity at 50 oC. These findings provide an important opportunity for the isolation of laccase from the residual substrate of Pleurotus ostreatus on a commercial scale. More importantly, treatment of crop residues with laccase will make available feed ingredients that contain minimal levels of lignin and polyphenols. Journal of the Ghana Science Association Vol. 10 (2) 2008: pp. 78-8

Biochemical composition and in vitro digestibility of cocoa (Theobroma cacao) pod husk, cassava (Manihot esculenta) peel and plantain (Musa paradisiacal) peel

The rational formulation of feeds using local agricultural by-products has been impossible owing to the paucity of research on the composition of such products. In this study, the composition and in vitro digestibility of three major plant by-products in the West African sub-region, namely cassava peel, plantain peel and cocoa pod husk have been analyzed to determine the content of protein, lipid, starch, soluble sugars and fibre. Cocoa pod husk contained the highest amount of protein (7.8 %) and fibre (26.9%) while cassava peel had the highest content of starch (9.1 %) and reducing sugars (3.8 %). The amount of lipid in plantain peel (6.0 %) exceeded those of the other two residues. Plantain peel and, to a lesser extent, cocoa pod husk contained substantial amounts of unsaturated fatty acids including linoleic acid, which is essential for pigs and poultry. Analysis of mineral elements showed high amounts of potassium were present in cocoa pod husk and plantain peel. Calcium levels were also high in cassava peel and cocoa pod husk. The rate of starch digestion in plantain peel was relatively high. However, in cocoa pod husk it was low and could have been caused by the high level of fibre. Treatment of residues with NaOH resulted in a marked increase in the rate of digestion of starch in cassava peels. Ghana Journal of Science Vol. 44, 2004: 29-3

Effectiveness of corn stalk ash in reducing tannin levels and improving In vitro enzymatic degradation of polysaccharides in crop residues

The condensed tannin content of three major plant by-products in the West African subregion, namely cassava peel (CP), plantain peel (PP) and cocoa pod husk (CPH) were measured. The values recorded for cassava peel and plantain peel were 2.0 and 1.8 per cent, respectively. Cocoa pod husk had the highest content (Amelonado–2.6 %; Tafo Hybrid–2.9 %; Amazonia–3.4 % dry wt). An aqueous extract of corn stalk ash, with a pH of 10.7, contained substantial amounts of potassium (51.0 ppm), sodium (16.4 ppm), chloride (22.4 ppm), and sulphate (9.5 ppm) ions. Treatment of the crop residues with corn stalk ash extract resulted in a timedependent reduction of condensed tannin content of all crop residues (84 % reduction in cocoa pod husk after 48 h of treatment) and improved in vitro rates of degradation of cellulose (CPH–72.1%, CP–116.1%, PP– 133.3 % after 48 h) and starch (CPH–107.5 %, CP–84.3 %, PP–82.2 % after 48 h). The findings suggest that treatment with corn stalk ash might be an effective means of detannifying and improving digestion of crop residues. Ghana Journal of Science Vol. 44, 2004: 87-9