Free radical scavenging activity of some fungi indigenous to Tanzania

The objective of this study was to evaluate free radical scavenging capacity of crude extracts from forest basidiomycetous fungi, domestic zygomycetous fungi and marine ascomycetous fungi. Lethal concentration values that kill 50% of the brine shrimps (LC50) were determined from 19 fungal extracts using brine shrimp test (BST). The LC50 values of fungal extract ranged between 0.28–40µg/ml. The basidiomycetous (Lactarius volemoides) was the most toxic fungi with LC50 of 0.28µg/ml while ascomycete Pichia guilliermondii showed the least toxicity with LC50 of 40µg/ml. The concentrations of eleven fungal extracts were further evaluated on their ability to scavenge free radical using 1-diphenyl-2-picrylhydrazyl (α,α-diphenyl-β-picrylhydrazyl) (DPPH) as a dye reagent for spectrophotometric assay at 517nm. The extract concentrations that decreased the initial DPPH radical by 50% (EC50) were determined. The EC50 values ranged from 19–60.4µg/ml ascorbic acid equivalents. Extracts from an edible but undomesticated basidiomycetous fungus isolated from Miombo forest and identified as Termitomyces microcarpus showed the highest scavenging effect with EC50 at 19µg/ml while that from ascomycete Candida tropicalis showed the least EC50 at 60.4µg/ml. These results draw attention to wild undomesticated Miombo fungi as potential source of nutritional supplements worth further investigation

Use of traditional medicines in the management of HIV/AIDS opportunistic infections in Tanzania: a case in the Bukoba rural district

Kisangau DP, Lyaruu HVM, Hosea KM, Joseph CC. Use of traditional medicines in the management of HIV/AIDS opportunistic infections in Tanzania: a case in the Bukoba rural district. Journal of Ethnobiology and Ethnomedicine. 2007;3(1): 29.Background: Ethnobotanical surveys were carried out to document herbal remedies used in the management of HIV/AIDS opportunistic infections in Bukoba Rural district, Tanzania. The district is currently an epicenter of HIV/AIDS and although over 90% of the population in the district relies on traditional medicines to manage the disease, this knowledge is impressionistic and not well documented. The HIV/AIDS opportunistic conditions considered during the study were Tuberculosis (TB), Herpes zoster (Shingles), Herpes simplex (Genital herpes), Oral candidiasis and Cryptococcal meningitis. Other symptomatic but undefined conditions considered were skin rashes and chronic diarrhea. Methods: An open-ended semi-structured questionnaire was used in collecting field information. Descriptive statistics were used to analyze the ethnobotanical data collected. Factor of informant consensus (Fic) was used to analyze the ethnobotanical importance of the plants. Results: In the present study, 75 plant species belonging to 66 genera and 41 families were found to be used to treat one or more HIV/AIDS related infections in the district. The study revealed that TB and oral candidiasis were the most common manifestations of HIV/AIDS opportunistic infections affecting most of the population in the area. It unveils the first detailed account of ethnomedical documentation of plants focusing the management of HIV/AIDS related infections in the district. Conclusion: It is concluded that the ethnopharmacological information reported forms a basis for further research to identify and isolate bioactive constituents that can be developed to drugs for the management of the HIV/AIDS opportunistic infections

Free radical scavenging activity of some fungi indigenous to Tanzania

The objective of this study was to evaluate free radical scavenging capacity of crude extracts from forest basidiomycetous fungi, domestic zygomycetous fungi and marine ascomycetous fungi. Lethal concentration values that kill 50% of the brine shrimps (LC50) were determined from 19 fungal extracts using brine shrimp test (BST). The LC50 values of fungal extract ranged between 0.28– 40μg/ml. The basidiomycetous ( Lactarius volemoides ) was the most toxic fungi with LC50 of 0.28μg/ml while ascomycete Pichia guilliermondii showed the least toxicity with LC50 of 40μg/ml. The concentrations of eleven fungal extracts were further evaluated on their ability to scavenge free radical using 1-diphenyl-2-picrylhydrazyl (α,α-diphenyl-β-picrylhydrazyl) (DPPH) as a dye reagent for spectrophotometric assay at 517nm. The extract concentrations that decreased the initial DPPH radical by 50% (EC50) were determined. The EC50 values ranged from 19–60.4μg/ml ascorbic acid equivalents. Extracts from an edible but undomesticated basidiomycetous fungus isolated from Miombo forest and identified as Termitomyces microcarpus showed the highest scavenging effect with EC50 at 19μg/ml while that from ascomycete Candida tropicalis showed the least EC50 at 60.4μg/ml. These results draw attention to wild undomesticated Miombo fungi as potential source of nutritional supplements worth further investigation

High temperature simultaneous saccharification and fermentation of starch from inedible wild cassava (Manihot glaziovii) to bioethanol using Caloramator boliviensis.

The thermoanaerobe, Caloramator boliviensis was used to ferment starch hydrolysate from inedible wild cassava to ethanol at 60°C. A raw starch degrading α-amylase was used to hydrolyse the cassava starch. During fermentation, the organism released CO2 and H2 gases, and Gas Endeavour System was successfully used for monitoring and recording formation of these gaseous products. The bioethanol produced in stoichiometric amounts to CO2 was registered online in Gas Endeavour software and correlated strongly (R(2)=0.99) with values measured by HPLC. The organism was sensitive to cyanide that exists in cassava flour. However, after acclimatisation, it was able to grow and ferment cassava starch hydrolysate containing up to 0.2ppm cyanide. The reactor hydrogen partial pressure had influence on the bioethanol production. In fed-batch fermentation by maintaining the hydrogen partial pressure around 590Pa, the organism was able to ferment up to 76g/L glucose and produced 33g/L ethanol

High temperature simultaneous saccharification and fermentation of starch from inedible wild cassava (Manihot glaziovii) to bioethanol using Caloramator boliviensis.

The thermoanaerobe, Caloramator boliviensis was used to ferment starch hydrolysate from inedible wild cassava to ethanol at 60°C. A raw starch degrading α-amylase was used to hydrolyse the cassava starch. During fermentation, the organism released CO2 and H2 gases, and Gas Endeavour System was successfully used for monitoring and recording formation of these gaseous products. The bioethanol produced in stoichiometric amounts to CO2 was registered online in Gas Endeavour software and correlated strongly (R(2)=0.99) with values measured by HPLC. The organism was sensitive to cyanide that exists in cassava flour. However, after acclimatisation, it was able to grow and ferment cassava starch hydrolysate containing up to 0.2ppm cyanide. The reactor hydrogen partial pressure had influence on the bioethanol production. In fed-batch fermentation by maintaining the hydrogen partial pressure around 590Pa, the organism was able to ferment up to 76g/L glucose and produced 33g/L ethanol

Production of raw starch-degrading enzyme by Aspergillus sp. and its use in conversion of inedible wild cassava flour to bioethanol.

The major bottlenecks in achieving competitive bioethanol fuel are the high cost of feedstock, energy and enzymes employed in pretreatment prior to fermentation. Lignocellulosic biomass has been proposed as an alternative feedstock, but because of its complexity, economic viability is yet to be realized. Therefore, research around non-conventional feedstocks and deployment of bioconversion approaches that downsize the cost of energy and enzymes is justified. In this study, a non-conventional feedstock, inedible wild cassava was used for bioethanol production. Bioconversion of raw starch from the wild cassava to bioethanol at low temperature was investigated using both a co-culture of Aspergillus sp. and Saccharomyces cerevisiae, and a monoculture of the later with enzyme preparation from the former. A newly isolated strain of Aspergillus sp. MZA-3 produced raw starch-degrading enzyme which displayed highest activity of 3.3 U/mL towards raw starch from wild cassava at 50°C, pH 5.5. A co-culture of MZA-3 and S. cerevisiae; and a monoculture of S. cerevisiae and MZA-3 enzyme (both supplemented with glucoamylase) resulted into bioethanol yield (percentage of the theoretical yield) of 91 and 95 at efficiency (percentage) of 84 and 96, respectively. Direct bioconversion of raw starch to bioethanol was achieved at 30°C through the co-culture approach. This could be attractive since it may significantly downsize energy expenses

Combined production of bioethanol and biogas from peels of wild cassava Manihot glaziovii

Cassava peels were pre-treated with alkali, enzyme and in sequential combination of alkali and enzyme, and used for production of bioethanol or biogas, or both (in sequence, bioethanol followed by biogas). The Biogas Endeavour and Automatic Methane Potential Test Systems were used for production of bioethanol and biogas, respectively. The bioethanol yield and volumetric productivity achieved with alkali pre-treatment combined in sequence with enzyme pre-treatment were 1.9 mol/mol and 1.3 g/L/h which was higher than the yield (1.6 mol/mol) and volumetric productivity (0.5 g/L/h) obtained from only enzyme pre-treated peels. Alkali combined in sequence with enzyme was proven to be the best treatment showing a 56% improvement in methane yield compared to the yield from untreated sample. Combined ethanol and methane production resulted in 1.2-1.3-fold fuel energy yield compared to only methane and 3-4-fold compared to only ethanol production. This study therefore provides practical data on the scenario best suited for the harnessing of energy from cassava peels. (C) 2015 Elsevier B.V. All rights reserved

Characterisation and evaluation of a novel feedstock, Manihot glaziovii, Muell. Arg, for production of bioenergy carriers: Bioethanol and biogas.

The objective of this study was to characterise and evaluate a wild inedible cassava species, Manihot glaziovii as feedstock for bioenergy production. Tubers obtained from 3 different areas in Tanzania were characterised and evaluated for bioethanol and biogas production. These bioenergy carriers were produced both separately and sequentially and their energy values evaluated based on these two approaches. Composition analysis demonstrated that M. glaziovii is a suitable feedstock for both bioethanol and biogas production. Starch content ranged from 77% to 81%, structural carbohydrates 3-16%, total crude protein ranged from 2% to 8%. Yeast fermentation achieved ethanol concentration of up to 85g/L at a fermentation efficiency of 89%. The fuel energy of the bioethanol and methane from flour-peels mix ranged from 5 to 13 and 11 to 14MJ/kgVS, respectively. Co-production of bioethanol and biogas in which the peels were added to the fermentation residue prior to anaerobic digestion produced maximum fuel energy yield of (15-23MJ/kgVS)

Traditional Knowledge, Use Practices and Conservation of Medicinal Plants for HIV/AIDS Care in Rural Tanzania

researchHIV/AIDS pandemic is currently the most socio-economic challenge that faces Tanzania as it affects mostly the young and most economically productive population. People living with HIV/AIDS in Tanzania are susceptible to fungal and bacterial opportunistic infections, which are a major cause of mortality and morbidity in the country. Despite the government’s intervention to provide ARVs to people living with HIV/AIDS, many of them especially those living in the rural areas can neither afford them due to poverty nor access them due to distance to health centers. Moreover, resistance of opportunistic microbial pathogens to conventional medicines and the serious side effects associated with antiretroviral drugs are also a major drawback to the management of HIV/AIDS in the country. Due to these factors, many people opt to use of traditional medicines. This paper highlights the use and conservation of herbal remedies to manage HIV/AIDS pandemic in Tanzania. Ethnobotanical surveys were carried out in Bukoba Rural District to explore the traditional ethno-medical knowledge, the use and conservation of medicinal plants in the management of HIV/AIDS opportunistic infections and to determine whether levels of harvesting are sustainable. The district is currently an epicenter of HIV/AIDS and although over 90% of the population in the district relies on traditional medicines to manage the disease, this traditional knowledge still remains largely unknown. Seventyfive plant species belonging to 66 genera and 40 families were found to be used to treat one or more HIV/AIDS related diseases in the district. Eight plant species were tested in-vitro for their antifungal activity against three major fungal pathogens, Candida albicans (C.P. Robin) Berkhout, Cryptococcus neoformans (San Felice) Vuill., and Aspergillus niger Tiegh. Three of them were further tested in-vivo for their anti-Candida activity. With decreasing natural stocks of medicinal plants, and based on the results, this study further provides concrete recommendations for the conservation of these important non-timber forest products and the region’s medicinal plant biodiversity