Screening of Antimicrobial Activity of Wild Mushroom from Khartoum State

Abstract

A survey was conducted in Khartoum State to collect 150 isolation of wild mushrooms from different areas. The areas of concern were forests, fields and river barks. The identified specimens were specified as Agaricus bernardii (26), Agaricus arvensis (19), Agaricus bisporus (42), Agaricus porphyrocephalus (25), Agaricus silvicola (5), Coprinus comatus (30) and Lepiota cristate (3). The petroleum ether, ethanol and aqueous extracts of mushrooms (A. bisporus, A. bernardii, A. arvensis, A. porphyrocephalus, C. comatus and L. cristata) were screened for their antimicrobial activity against four different references bacteria: one Gram positive (Staphylococcus aureus ATCC 25923), three Gram negative (Escherichia coli ATCC 25922, Pseudomonas aeroginosa ATCC 27853 and Proteus vulgaris NCTC 8196) and against two references ftmgi (Aspergillus niger ATCC 9763 and Candida albicans ATCC 7596) using the cup plate agar diffiision method. All ethanol extracts exhibited inhibitory effects against three or more of the tested organisms. Ethanol extract of Agaricus porphyrocephalus was found superior and active against all of the tested organisms. Escherichia coll was the most sensitive organism as it was inhibited by nine extracts (52.9%) and Candida albicans inhibited by seven extracts (41.2%). While Aspergillus niger was the most resistant organism that was inhibited by two extracts (11.8%). Petrolemn ether extracts of all mushrooms were inactive against the tested microorganisms except the extracts of Agaricus porphyrocephalus, Agaricus bernardii and Coprinus comatus which were active against Escherichia coli only. Water extracts of all mushrooms on the other hand, were also inactive against all of the tested microorganisms except the water extract of Agaricus porphyrocephalus that was active against one bacteriiun (Staphylococcus aureus) and two fungi (Candida albicans and Aspergillus niger). The minimum inhibitory concentrations (MICs) of the most active ethanolic extracts of the six mushrooms against standard bacteria were also determined. It was found that MICs a ranging between concentration 2.5-5 (mg\mL). The antibacterial activity of four reference antibiotic dmgs and the antifungal activity of two reference drugs were determined against the tested four bacteria and two fungi and their activities were compared to the activities of mushroom extracts. Results obtained indicated that Gentamicin showed high activity against all tested bacteria, but the petroleum ether and ethanolic extracts of Agaricus porphyrocephalus inhibited Escherichia coli more than l0ug\m1 of Gentamicin, ethanolic extract of Agaricus bisporus inhibited Pseudomonas aeruginosa similar to 20ug\m1 of Gentamicin, petroleum ether extract of Agaricus bernardii and ethanolic extract of Coprinus comatus inhibited Escherichia coli similar to 1Oug\ml of Gentamicin. Clotrimazole showed high activity against all tested fungi and inhibited standard Candida albicans higher than any one of mushroom extracts. All of the mushroom extracts were phytochemically screened and carbohydrates, reduced sugar, flavonoids, alkaloids, saponins, sterols, coumarins and triterpens were present in all of the mushrooms samples.