Journal of Natural Sciences Research www.iiste.org ISSN 2224-3186 (Paper) ISSN 2225-0921 (Online) Vol.5, No.13, 2015 36 Radical Scavenging Properties, Total Polyphenols and Flavonoids of Two Coloured Basidiomycetes from Four Pre-Determined Phases G.I. Nattoh 1* ; G.E. Gatebe 3, 4 ; J.M. Maina 1, 2 ; F. Musieba 4 1. Department of Molecular Biology & Biotechnology, Pan African University, Institute for Basic Sciences, Technology & Innovation- (PAUISTI), P.O Box 62000-00200 Nairobi Kenya 2. Department of Food Science & Technology, Jomo Kenyatta University of Agriculture Science & Technology P.O Box 62000-00200 Nairobi Kenya 3. Chemistry Department, Jomo Kenyatta University of Agriculture Science & Technology P.O Box 62000- 00200 Nairobi Kenya 4. Mushroom section, Food Division, Research Technology & Innovation Department, Kenya Industrial Research and Development Institute P.O Box 30650-00100 Nairobi Kenya bstract Prospects to evaluate appropriate harvest phase for edible basidiomycetes providing optimal value added health promoting benefits are limited in mushroom entrepreneurship. Two colored edible basidiomycetes (golden yellow Pleurotus citrinopileatus singer and pink Pleurotus djamor R22) were selected for the determination of Total Flavonoid, Total phenols, and free radical scavenging properties at spawn mycelia and three predetermined phases. Using 1, 1-diphenyl-2-picrylhydrazyl (DPPH) assay, antioxidative properties of young basidiocarps were relatively higher with EC 50 values lower than mature fruiting bodies (3.176±0.905mg/mL against 10.787±1.007mg/mL) for P. djamor while P. citrinopileatus reported 7.321±1.291mg/mL against 10.502±1.017mg/mL. Antioxidant capacity collaborated the phenolics determined using Folin Ciocalteu Assay, young basidiocarps of P. djamor recorded higher values 12.655±1.019 against mature 4.317±0.921 mgGAE/ g dry weight) with P. citrinopileatus reporting 8.726±0.801 against 4.512±0.310 mgGAE/ g dwt. A strong correlation between phenols and the scavenging properties in aqueous extraction (R 2 =0.844, y=-0.700x +13.27 for yellow and R 2 =0.983, y=-0.896x +14.29 for pink oyster) was noted. Flavonoid contents did not show a linear correlation with the period, antioxidative, or phenolics properties. Early basidiocarps and basidiospores of basidiomycetes contain bioactive molecules worth targeting for value addition in formulating food supplements or pharmaceutical products. Keywords: DPPH, growth phase, antioxidant, colored basidiomycetes, polyphenols, flavonoids, Pleurotus djamor R22, P. citrinopileatus 1.0 Introduction Edible fungi are rich sources of health promoting molecules like polyphenols, flavonoids and radical scavenging properties (Ferreira et al., 2009). The value added health benefits of edible basidiomycetes has been studied because they posses protein, minerals, vitamins, unique taste, and flavor (Pereira et al., 2012; Reis et al., 2012a; 2012b). In the past mushroom studies have attracted attention because of their ability to treat or prevent diseases (Chang, 1996). Studies shows that edible fungi in the genera Pleurotus spp, Agaricus spp, and lentinula spps exhibits antibacterial (Hirasawa et al., 1999; Oyetayo, 2009), antioxidative, anti-allergic, reduces blood cholesterol levels (Jeong et al., 2010) anti-tumor (Ferreira et al., 2010) and immunomodulatory effects (Valko et al., 2007), and antioxidant properties (Mohamed, et al., 2011; Soobrattee, et al., 2005b). Besides, they have been documented as rich sources of bioactive molecules that confer health promoting benefits against degenerative heart diseases, cancers, and diabetes (Soobrattee, et al., 2009; Cheung, et al., 2003). These have elicited pharmacological and nutraceutical interests because inherent natural antioxidative and repair mechanisms that normally protect the body are inadequate to sufficiently prevent antioxidative stresses generated within (Simic, 1998; Barros et al., 2008; Reis et al., 2012b). Metabolisms in the body generate free radicals, which are chemically unstable and can damage cytoplasmic molecules like proteins, lipids, and DNA (Barros et al., 2008). These radicals are manifested when the enzymatic systems protecting the body from oxidative stress is overwhelmed with excess generation of radicals like reactive oxygen species (ROS), which results in imbalances (Nijveldt, et al., 2001). However, natural products with potent secondary metabolites would scavenge for such radicals (Dubost, et al., 2007; Soobrattee, et al., 2005; 2009). Health promoting benefits like antioxidant associated with polyphenols can add value to the product developed from potential sources like novel mushrooms (Scalber et al., 2005). The main challenge is the possibility of producing mushroom products with maximum intact phenols, flavonoids and other bioactive molecules. Most entrepreneurs in this emerging industry have no idea on what stage the fruiting bodies should be collected to maximize on these benefits. Studies by Barros et al (2007a) brought to you by CORE View metadata, citation and similar papers at core.ac.uk provided by International Institute for Science, Technology and Education (IISTE): E-Journals