Evaluation of Anti-fungal Activity of Coleus Species Extracts

Abstract

A b s t r a c t A r t i c l e I n f oAntifungal activity of 50%-methanol, water and absolute methanol extracts of Coleus species (whole plant) was evaluated using agar, and macro-broth dilution methods. The test microorganisms were strains of Aspergillus, Rhizopus, Mucor, Rodotorula, Geotricum, Basidiobolus, Trichophyton, Microsporum, Epidermophyton and Candida. The yields achieved with extracts were 24%, 22% and 29% for absolute methanol, water and 50% methanol extracts, respectively. The phytochemical analysis of the extracts revealed the presence of flavonoids, alkaloids, tannins, cardiac glycosides, carbohydrates, steroids, Proteins, glycosides and anthracene glycosides. All (100%) fungal strains tested were susceptible to all the extracts. The observation of the growth inhibition of the fungi tested lasted for 7-14 or more days of incubation on Sabouraud Dextrose agar plates. MIC range was 0.146-15.63mg/ml and Candida albicans was the most susceptible of the yeasts tested (MIC 90 0.78mg/ml), Epidermophyton floccosum, the most susceptible dermatophyte (MIC 90 = 1.56mg/ml), while T. tonsurans was the least susceptible of the fungi tested (MIC 90 25mg/ml) and these results are consistent with the time kill observed with the extracts. Results authenticated the folklore medicinal usage of Coleus species for treatment of gastrointestinal, reproductive tract and skin infections.

Antifungal Effects of Combined Extracts of Euphorbia abyssinica and Coleus Species

“…In ethnomedicine, plant extracts are often used in different combinations, but the precise quantity of each constituent is not known. However, they still remain the preferred method of treatment in most local and underdeveloped areas of the world where the orthodox drugs are not easily available [29].…”

“…There had been reports of the same pattern of antimicrobial effects of alcohol extracts of Coleus sp. by Jay, [34] and Tarh and Iroegbu [29].…”

“…The susceptibility testing of fungi was done using a pour-plate method as described by Tarh and Iroegbu, [29]. A 2.0 mL amount of a 1000 mg/mL of the reconstituted plant extract was pipetted into a sterile glass test tube containing 18mL of molten Sabouraud Dextrose Agar (SDA) at about 45°C.…”

“…Additivity or indifference was described as a < 2 log 10 CFU/mL change in the average viable counts after the incubation periods for the combination, in comparison with the most active single drug. Antagonism was defined as a ≥ 2 log 10 CFU/mL increases in colony counts after the incubation periods by the combinations; compared to that of the most active single extract alone [29]. All the experiments were performed in quadruples and the data collected from four repeated experiments were analysed using the Randomised Complete Block Design (Two-way analysis of variance).…”

Antifungal Evaluation of Alcoholic Extract of Euphorbia zeylanicum

“…The resultant supernatant suspensions were drained into sterile bottles. The spores or yeast cells (colony forming units (CFU)) in the suspensions were counted using a haemocytometer and the suspensions were then diluted with Sabouraud dextrose broth to correspond to the final standard inoculate suspension (spores or yeast cells) of approximately 1 x 10 5 colony forming unit per ml 8 .…”