Akademik Veri Yönetim Sistemi
3rd INTERNATIONAL EURASIAN MYCOLOGY CONGRESS (EMC’22), Van, Türkiye, 7 - 09 Eylül 2022, ss.120-121, (Özet Bildiri)
Oxidative stress can cause many serious health problems in the body, including heart disease, neurological disorders, diabetes and leukemia. Today, some medicinal plants and mushrooms consumed as food may be effective in preventing these diseases. In this respect, it is important to determine the number of phenolic compounds they contain and their antioxidant effects. Tricholoma terreum (Schaeff.) P. Kumm. belongs to Tricholomataceae family, it has 4-7 cm wide cap and evenly covered in fine grey scales. Convex with a slight boss, it is broadly conical in shape. Tricholoma terreum, which is one of the edible mushroom species, is known as “karakız” mushroom in our country. The aim of our study is to evaluate and compare Tricholoma terreum extracts in terms of antioxidant, antidiabetic, antimicrobial effects and total phenolic compound. This species, which was dried under suitable conditions, was weighed 50 grams and powdered by a grinder and macerated with methanol at room temperature via a mechanical mixer at 200 rpm. The prepared main extract was filtered and evaporated in a rotavapor. The subfractions were prepared by using solvents of different polarities (n-hexane, dichloromethane, ethyl acetate, n-butanol) based on the main extract. These main extract and sub-fractions were evaluated for their antioxidant capacities by ABTS• and DPPH• methods, and phenolic content using Folin-Ciocalteu’s reagent (FCR) with slight modifications. In the antioxidant capacity tests, α-tocopherol (TK) and trolox (TR) were used as standard. The total phenolic compound amounts of the extracts were expressed as gallic acid equivalents in µg/ml. In vitro α-glucosidase inhibition assays were carried out according to method of Tao et al. 2013, in vitro α-amylase inhibitory activity was determined by the method of Nampoothiri et al. 2011 with slight modification. The results of both experiments are expressed by comparison with the standard acarbose. Antimicrobial activities were evaluated by microdilution method with some modifications against Escherichia coli ATCC 8739, Staphylococcus aureus ATCC 6538, Candida albicans ATCC 10231. Moxifloxacin, ampicillin, and fluconazole used as standard were prepared at 128 µg/ml. Morphological examination of fungal spores was made in a Jeol JSM 6490LV scanning electron microscope at the Turkish Petroleum International Company (TPAO) Research Center SEM laboratory in Ankara. The extracts of T. terreum, n-butanol (B) extract showed highest activity compared to methanol extract (M), n-hexane (H), dichloromethane (D), ethyl acetate (E) and aqueous (A) extract. [(TR)96.5>(TK)90.1>(B)15.8>(E)12.3>(A)10.9>(M)5.2 %; at 60 μg/ml for ABTS)]. [(TR)93.3>(TK)91.9>(B)4.2>(E)3.4>(A)1.4>(M)1.2>(D)0.4 %; at 100 μg/ml for DPPH)]. Total phenolic compound test results for T. terreum [(B)11.3>(E)9.3>(A)7.1>(M)5.5>(D) 1.1 µg GAE/ mg extract]. n-Hexane extract did not show any effect at the determined concentrations. The ethyl acetate extract of T. terreum showed the highest α-glucosidase inhibitory effect [(A)56.6>(E)0.2; at 5000 µg/ml)]. No significant activity was observed in the other extracts. The n-hexane extract of T. terreum showed the highest α-amylase inhibitory effect [(A)38.7>(H)21.3>(M)14.3>(D)14.1>(E)6.7>(B)5.9; at 5000 µg/ml)]. Ethyl acetate extract of T. terreum showed best antimicrobial activity against C. albicans with MIC=62.5 µg/ml. All of the extracts showed similar antimicrobial activity against E. coli, S. aureus. The spore shape is ellipse, with dimensions of 6-7 µm on the long axis and 4-5 µm on the short axis. In a conclusion; our results should be useful in future studies about this species. Acknowledgement: BİLGE AYDIN and Enes TEKMAN would like to acknowledge the scholarship during their postgraduate program provided by the Turkish Scientific and Technical Research Council (TUBITAK).
KEYWORDS: Tricholoma terreum, antioxidant, diabetes, antimicrobial, morphologic analysis