Cancer Preventive Potential of Methanol Extracts of Hypsizigus marmoreus
ABSTRACT Hypsizigus marmoreus has recently become a popular edible mushroom in Asia. Despite its extensive use, the underlying mechanisms of the anticarcinogenic effects on the initiation stage are not precisely known. Therefore, methanol extracts from H. marmoreus were prepared and then tested for antiproliferative effects in cancer cells and antimutagenic activities as well as mutagenic capacity using the Ames Salmonella mutagenicity test. In addition, the effects on the phase I drug metabolizing enzymes, phase II detoxifying enzymes, and antioxidative activities were evaluated in livers from mice pretreated with methanol extracts from H. marmoreus and challenged with benzo[a]pyrene (B[a]P). In the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, methanol extracts from H. marmoreus displayed a dose-dependent inhibitory effect against human hepatocarcinoma and colon carcinoma cells. However, equivalent doses did not induce mutagenicity when tested with Salmonella typhimurium TA98 and TA100 while exhibiting antimutagenicity against direct-acting and indirect-acting mutagens. Methanol extracts from H. marmoreus strongly decreased total cytochrome P450 and activity of ethoxyresorufin deethylase after B[a]P challenge. Further investigation revealed that methanol extracts from H. marmoreus decreased protein levels of cytochrome P450 IAI isozyme induced by B[a]P. Methanol extracts from H. marmoreus increased the content of glutathione and activity of glutathione S-transferase. This also induced the activity of quinone reductase, an enzyme well known to be anticarcinogenic. The results of the present study therefore demonstrated that methanol extracts from H. marmoreus may have antimutagenic effects, inhibiting the mutagenicity of some mutagens, particularly indirect-acting B[a]P. The mechanism of this antimutagenicity may be the induction of the activity of phase II enzymes, as well as the ability to reduce phase I metabolic-activating enzymes in mouse liver.
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- "In the last two decades, a wide range of evidence from epidemiological and laboratory studies have demonstrated that some plants eaten whole, or some of their active principles taken in isolation, have substantial protective effects against human carcinogenesis and mutagenesis (Surh and Ferguson, 2003). Several plant extracts have proved to contain a wide variety of antimutagenic substances (Verschaeve et al., 2004; Scassellati- Sforzolini et al., 1999; Khader et al., 2010; Wongwattanasathien et al., 2010; Kaur et al., 1998, 2000, 2001, 2009) and some can prevent cancer (Nishino, 1998; Saleem et al., 2005; Chang et al., 2009; Hu et al., 2010; Inayat-Hussain et al., 2010). A. cadamba (Roxb.) "
ABSTRACT: Anthocephalus cadamba (Roxb.) Miq. (Rubiaceae), an Ayurvedic medicinal plant is ethnomedicinally widely used in the treatment of fever, anaemia, uterine complaints, blood diseases, skin diseases, leprosy, dysentery, and for improvement of semen quality. The present work was carried out to evaluate the antioxidant potential of methanol extract from the bark of A. cadamba. The antioxidant activity was determined by in vitro assays viz. DPPH radical scavenging assay, ABTS radical cation decolorization assay and reducing power assay. The extract was evaluated for DNA protection activity in DNA protection assay using pBR322 plasmid DNA. The various antioxidant activities were compared to standard antioxidants such as butylated hydroxytoluene and ascorbic acid. The extract showed potent antioxidant activity in all the assays. The percentage inhibition of DPPH radical was 77.97±0.301% and for ABTS it was found to be 91.70±0.40% at a concentration of 200 μg/ml. The reducing power was observed to be 59.47±0.801% at the highest tested dose of 1000 μg/ml. The extract also showed good genoprotective potential comparable to gallic acid. In addition to the antioxidant activity of the extract, the total phenolic content and total flovonoid content were also measured.
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ABSTRACT: A protease with a molecular mass of 28 kDa, designated as hmsp, was isolated from fresh fruiting bodies of the edible mushroom Hypsizigus marmoreus. The purification protocol entailed ion exchange chromatography on DEAE-cellulose, CM-cellulose, and FPLC-gel filtration on Superdex 75. The protease was unadsorbed on DEAE-cellulose but adsorbed on CM-cellulose. hmsp was thermolabile, and exhibited a temperature optimum at 50 °C and a pH optimum at pH 7.5. The activity of the protease was adversely affected by PMSF, EGTA and aprotinin, indicating that it is a serine protease. Based on the N-terminal sequence, the cDNA of hmsp was cloned by using RACE combined with the TAIL-PCR method. The deduced protease sequence contained a signal peptide with 19 amino acids, a pro-region with 82 amino acids, and a mature protease with 285 amino acids and a molecular mass of 28.07 kDa. It possessed the three active sites characteristic of the subtilisin family (S8A). hmsp demonstrated 63%, 57% and 44% identity in amino acid sequence respectively to Absp1, Absp2, and Gf-spr1, which are serine proteases from Agaricus bisporus and Grifola frondosa.PROCESS BIOCHEMISTRY 05/2010; 45(5-45):724-730. DOI:10.1016/j.procbio.2010.01.009 · 2.52 Impact Factor
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ABSTRACT: This study was carried out to investigate whether Chrysanthermum zawadskii var. latilobum Kitamura (C. zawadskii) extracts has an inhibitory effect against the mutagenicity by cigarette smoke condensates (CSC). C. zawadskii was extracted with 70% ethanol and the yield was 18.5%. We further fractioned 70% ethanol extract sequentially to diethylether, chloroform, dichloromethane, and aqueous water, and gained the yield of 17.5%, 5.6%, 5.8%, 32.8% and 35.5%, respectively. In the Ames test, there was no mutagenic effect of crude extract and its solvent fractions up to 2 mg/plate toward Salmonella typhimurium TA 98 with or without S-9 mix metabolic activations. On the contrary, the crude extract showed an inhibitory activity against the mutagenicity of CSC in the presence of S-9 mix metabolic activation. Diethyl ether layer among five solvent fractions showed the highest inhibitory activity. The inhibitory activity of diethyl ether fraction was also increased in a dose-dependent manner and the inhibitory rate was about 97.7% at the concentration of 1 mg/plate. In this study, we conclude that crude extract of C. zawadskii itself is potentially safe for mutagenicity, and the diethyl ether fraction has an inhibitory effect against the mutagenicity of CSC.06/2011; 19(3). DOI:10.7783/KJMCS.2011.19.3.170