Akademik Veri Yönetim Sistemi
3rd INTERNATIONAL EURASIAN MYCOLOGY CONGRESS (EMC’22), Van, Türkiye, 7 - 09 Eylül 2022, ss.122-123, (Özet Bildiri)
Free radicals are highly reactive, short-lived, and unstable molecules that occur as a product of normal metabolism in the body or are caused by environmental factors. They need to bind to other molecules in order to become more stable and survive longer. However, the molecules to which they are bonded also lose an electron and turn into free radicals. This cycle continues in a balance in the organism. When the balance between oxidant and antioxidant molecules is disturbed in favor of oxidants, various metabolic diseases occur. Many studies have also shown that there is a relationship between diabetes and free radicals. Again, studies have shown that antioxidant-effective compounds have antimicrobial effects on microorganisms. The aim of our study is to evaluate and compare Clitocybe nebularis (Batsch) P. Kumm. extracts in terms of antioxidant, antidiabetic, antimicrobial effects and total phenolic compound. The genus Clitocybe belongs to Tricholomataceae family. Clitocybe nebularis inhabits coniferous and mixed forests and forms its fruiting bodies during late summer and early autumn, usually in fairy rings, which known as “dumanlı mantar, kara balkadın” in our country. Although C. nebularis is known as an edible mushroom, it can cause stomach problems. Dried mushroom (50 g) was powdered 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 and sub-fractions were prepared by treating with solvents of different polarities (n-hexane, dichloromethane, ethyl acetate, n-butanol). These extracts 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 ABTS•+ and DPPH• scavenging activity tests, α-tocopherol (TK) and trolox (TR) were used as standard. The total phenolic component amounts of the extracts were expressed in gallic acid equivalents. 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. Antimicrobial activities were evaluated by microdilution method with some modifications against Escherichia coli ATCC 8739, Staphylococcus aureus ATCC 6538, Candida albicans ATCC. 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 C. nebularis, 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)34.8>(E)20.4>(A)19.1>(D)12.8>(M)5.4>(H)1.5%; at 60 μg/ml for ABTS)]. [(TR)93.3>(TK)91.9>(B)8.0>(E)6.3>(A)5.5>(D)3.8>(M)3.4>(H)2.7%; at 100 μg/ml for DPPH)]. Total phenolic compound test results for C. nebularis [(B)26.3>(E)16.3>(A)12.6>(D)12.1>(M)7.7>(H) 4.2 µg GAE/ mg extract]. In the α-glucosidase and α- amylase inhibitory activity of C. nebularis extracts, acarbose (A) was used as standard. The n-hexane extract of C. nebularis showed the highest α-glucosidase inhibitory effect [(A)56.59>(H) 22.88; at 5000 µg/ml)]. The dichloromethane extract of C. nebularis showed the highest α-amylase inhibitory effect [(A)38.65>(D)17.30; at 5000 µg/ml)]. No significant activity was observed in the other extracts. All of the extracts showed similar antimicrobial activity. nHexane, n-butanol and ethyl acetate extracts were found to be effective against C. albicans (MIC=125 µg/ml). The spore shape is pyriform or oblong, with dimensions of 6.5-8.5 µm on the long axis and 3.5-4.5 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: Clitocybe nebularis, antioxidant, diabetes, antimicrobial, morphologic analysis