Free Radical Scavenging Activity of Some Fungi Indigenous to Tanzania

Abstract: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- 40?g/ml. The basidiomycetous ( Lactarius volemoides check for this species in other resources ) was the most toxic fungi with LC50 of 0.28?g/ml while ascomycete Pichia guilliermondii check for this species in other resources showed the least toxicity with LC50 of 40?g/ml. The concentrations of eleven fungal extracts were further evaluated on their ability to scavenge free radical using 1-diphenyl-2-picrylhydrazyl (?;?-diphenyl-?-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 19-60.4?g/ml ascorbic acid equivalents. Extracts from an edible but undomesticated basidiomycetous fungus isolated from Miombo forest and identified as Termitomyces microcarpus check for this species in other resources showed the highest scavenging effect with EC50 at 19?g/ml while that from ascomycete Candida tropicalis check for this species in other resources showed the least EC50 at 60.4?g/ml. These results draw attention to wild undomesticated Miombo fungi as potential source of nutritional supplements worth further investigation

Microbiological Indoor and Outdoor Air Quality of Two Major Hospitals in Benin City; Nigeria

Air contains large number of microorganisms including bacteria and fungi and their estimation is important as an index of cleanliness for any particular environment. It becomes imperative to undertake a study of the microbiological air quality of the airborne micro-flora in the environments of two major government hospitals; University of Benin Teaching Hospital (UBTH) and Central Hospital; in Benin City metropolis. Both indoor and outdoor air samples were assessed monthly for the three (3) months in the wet season (June - August; 2010) and dry season (November 2010 - January 2011) using the settled plate methods. The study sites were divided into nine (9) units which include accident and emergency ward; laboratory; male ward; female ward; children ward; labour room; treatment room; theatre and outside the hospital gate. The mean airborne bacterial load in the two hospitals ranges from 8.5cfu/min to 172.5cfu/min and 5.5cfu/min to 64.5cfu/min for UBTH and Central hospital in the wet season. While the mean airborne fungal load in UBTH and Central Hospital in dry season ranges from 2.5cfu/min to 9.5cfu/min and 1.5cfu/min to 19.0cfu/min respectively. The female ward; children ward; accident and emergency ward and outside the hospital gate recorded the highest airborne micro-flora. The result revealed the isolation of ten (10) fungal isolates and six (6) bacterial isolates. These include Aspergillus niger; Aspergillus flavus; Botryodiplodia acerina; Rhizopus stolonifer; Nigospora zimm; Mucor sp.; Monilla infuscans; Penicillium sp.; Candida sp. and Trichoderma viridis while the six (6) bacterial isolates include Staphylococcus aureus; Staphylococcus epidermidis; Bacillus cereus; Bacillus sp.; Serratia marcescens and Micrococcus sp. The result shows the highest fungal population of 26.5cfu/min (outdoor) in UBTH followed by 24.0cfu/min (outdoor) in Central Hospital. The highest bacterial load of 172.5cfu/min (outdoor) was recorded in UBTH. The fungal isolates Aspergillus niger (53.0) and Monilla infuscans (43.9) were showed to be the most frequently isolated airborne fungal organisms while Staphylococcus aureus (91.3) and Staphylococcus epidermidis (85.8) were the most frequently isolated bacterial isolates. The statistical analysis showed no significant difference between the microbial population obtained during the wet and dry seasons in both hospitals studied. Data generated underline the usefulness of monitoring hospital environments

Antimicrobial activity of leaf extracts of Senna obtusifolia (L)

Antimicrobial properties of leaf extracts of Senna obtusifolia (L) were investigated against both clinical and laboratory isolates of both bacteria and fungi using the disc diffusion method. Acetone extracts (12 mm zone diameter of inhibition, MIC 200 g/mL and MBC 300 g/mL) demonstrated the highest activity, followed by dichloromethane (8 mm zone diameter of inhibition, MIC 300 g/mL and MBC 400 g/mL), methane (7 mm zone diameter of inhibition, MIC 400 g/mL and MBC 400 g/mL) and hexane (6 mm zone diameter of inhibition, MIC 800 g/mL and MBC 1000 g/mL). Water extracts demonstrated the least activity against the test bacteria and fungi (4 mm zone diameter of inhibition, MIC 800 g/mL and MBC 800 g/mL). Phytotoconstituents present included Saponins, Tannins, Alkaloids and Flavonoids. S. obtusifolia (L) can be used to source antibiotic substances for possible treatment of bacterial and fungal infections including gonorrhea, pneumonia, urinary tract and some mycotic infections

Activites antifongiques de deux huiles essentielles sur les champignons des feves de cacao et de levures : Candida albicans et Cryptococcus neoformans

Les activites quotidiennes de l'homme l'exposent a la pollution environnementale par des microorganismes dont les champignons qui peuvent occasionner chez lui des mycoses ou detruire les produits vegetaux. Face e cela; les moyens de lutte employes se revelent plus ou moins efficaces mais sont; parfois dangereux. Chez le cacao la presence des toxines fongiques est a l'origine de la deterioration de sa qualite. Ainsi; sur des feves de provenances diverses; des especes Fongiques ont ete isolees par secousse et a partir d'un ecouvillon frotte aux Feves. Ensuite; il e ete teste deux huiles essentielles comestibles extraites de vegetaux ivoiriens. (Chenopodium ambrosioides et Melaleuca quinquenervia a 1 ml/L; 5 ml/L et 10 ml/L sur Aspergillus sp; Aspergillus niger; Aspergillus fumiganus; Mucor racemosus; Candida albicans et Cryptococcus neoformans. Aussi; une protection des feves de cacao par l'huile de Melaleuca quinquenervia a ete experimentee. Suite a ces differentes experiences; il a ete retenu d'une part; qu'a 1 ml/L et 5ml/l ces huiles essentielles ont des activites antifongiques. D'autre part. a 1ml/l Chenopodium ambrosioides agirait comme un Fongicide dans notre experience contrairement a l'huile de Melaleuca quinquenervia. Mais a 5 ml/1; l'huile de Melaleuca quinquenervia empeche le developpement de A. flavus; A. fumigatus; A. niger; Aspergillus sp; M. racemosus; Penicillium sp sur les feves de cacao pendant un mois. Ces experiences ont permis d'elucider l'impact de chacune des huiles sur les champignons. Vu la diversite de leurs activites; ces deux huiles essentielles pourraient etre utilisees comme produits antifongiques de lutte contre les champignons dans l'environnement et contre certaines mycoses

Les champignons dans les pharmacopees traditionnelles de l'Afrique de l'Ouest

Ce premier inventaire; non exhaustif; des champignons superieurs utilises en pharmacopee traditionnelle en Afrique de l'Ouest; nous revele une richesse insoupconnee pour une region aride et consideree comme ayant une flore mycologique pauvre. Or les populations locales n'ont pas neglige l'apport des champignons dans la pharmacopee; leur usage semblant meme plus important que dans les pharmacopees occidentales qui; a de rares exceptions; ont neglige les champignons; sauf bien entendu les champignons inferieurs generateurs d'antibiotiques (bezanger-beauquesne; 1983). Il y aurait peut-etre interet a approfondir les recherches de ce cote la; nen particulier l'analyse chimique; qui ne devrait pas decevoir; en raison de la richesse previsible des champignons superieurs en molecules d'interet biologique