Browsing by Author "Chove, B.E."

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Comparative evaluation of different methods of extraction and purification used in technical enzyme production from microorganisms
(1998) Gidamis, A.B.; Nnko, S.A.; Shayo, N.B.; Chove, B.E.; Kroner, H. K.
A stlldy was conducted to compare the efficiency of two methods of microbial cell separation and enzyme purification using penicillin-G-acylase (PGA) from Escherichia coli. The efficiency of two methods of ceJ[ separation; centrifugation and cross flow filtration (CFF) were compared. The CFF method was found to have both higher separation efficiency and enzyme yield than centrifugation method. Centrifugation method gave a separation efficiency of 98.5% with enzyme yield of94 % whereas CFFmethod resulted in 100% separation efficiency and enzyme yield of98.8%. The Escherichia coli cells were disrupted by high pressure homogenization (HPH),and the disrupted cells were purified using two different techniques. Technique I was a combination of cross-flow-diafiltration (CFD) , ultrafiltration (UF) and heat/pH-shift treatments. This technique resulted in 47% enzyme yield with a purification factor of 12. Technique II which involved two extraction steps by' aqueous two - phase system (APS) coupled with UF resulted in 62 % enzyme yield with a pu;ificationfactor of 4. Technique I was therefore much better than techriique Il in purifying the enzyme. For higher enzyme yield, technique II would seem to be a better one than technique I.
Farmers' knowledge and traditional processing practices of pigeon peas (Cajanus cajan) in Rural Areas in Lindi Region Tanzania: a quantitative and qualitative mixed study
(AJOL, 2024) Tiisekwa, A.B.; Chove, B.E.; Mongi, R.; Raybak, C.; Stuetz, W.
Pigeon peas (Cajanus cajan) are an important protein source in many parts of tropical and sub-tropical regions of the world. However, their quality and availability may be affected by post-harvest handling and processing practices in use. In the present study, knowledge and practices of pigeon pea growers (PPG) in Lindi Region were evaluated with respect to harvesting, storage, processing and cooking preparation. A sample of 597 randomly selected PPG from two villages, were interviewed and 60 farmers participated in focus group discussions. Majority PPG (83.6%) harvested pigeon peas (PPs) by cutting and putting them in polyethylene sacks while 86.6% had knowledge on only one storage method. Also, majority of PPG (77%) lacked any processing knowledge on mentioned methods such as hulling and solar drying. Results also indicated 75.7% of PPG having no knowledge on cooking preparation methods out of which 94.5% had no knowledge on soaking, 89.6% on use of bicarbonate and 89.9% on methods to increase shelf life of PPs. Overall, 49.4% had little/limited knowledge on harvesting, storage, processing, and cooking preparation practices, with no significant gender difference. All PPG prepared stew using green or dry PPs. A sizeable proportion (45%) of PPG used dry PPs for stew preparation, after traditional hulling. The threshing of peas from pods was carried out manually. Traditional methods in the Lindi Region are laborious and time-consuming; resulting in poorly prepared products thus affecting the appearance of processed PPs. Training farmers on proper postharvest handling and processing can improve food security and market appeal.