A new ganoderic acid from Ganoderma lucidum mycelia and its stability
ABSTRACT A new ganoderic acid (GA), 3α,22β-diacetoxy-7α-hydroxyl-5α-lanost-8,24E-dien-26-oic acid (1), together with four known compounds GA-Mk (2), -Mc (3), -S (4) and -Mf (5), were isolated and characterized from Ganoderma lucidum mycelia. The structure of compound 1 was elucidated on the basis of interpretation of extensive spectroscopic data (HRMS, IR, UV, 1D and 2D NMR). Due to its apparent degradation during preparation procedures, the stability of compound 1 was assessed in several solvents in a short-term study that demonstrated the optimal stability in aproptic environment. A possible mechanism of acid-catalyzed degradation of compound 1 in methanol was proposed, consisting of a fast protonation, followed by a committed step of hydroxyl group removal. In addition, all isolated compounds were tested in vitro for their cytotoxic activities against 95D and HeLa tumor cell lines, with IC(50) values ranging from14.7 to 38.5μM. The results may improve the understanding of chemical stability of GAs and provide valuable information on their separation, analysis and application.
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ABSTRACT: Exploration of natural sources for novel bioactive compounds has been an emerging field of medicine over the past decades, providing drugs or lead compounds of considerable therapeutic potential. This research has provided exciting evidence on the isolation of microbe-derived metabolites having prospective biological activities. Mushrooms have been valued as traditional sources of natural bioactive compounds for many centuries and have been targeted as promising therapeutic agents. Many novel biologically active compounds have been reported as a result of research on medicinal mushrooms. In this review, we compile the information on bioactive structure-elucidated metabolites from macrofungi discovered over the last decade and highlight their unique chemical diversity and potential benefits to novel drug discovery. The main emphasis is on their anti-Alzheimer, antidiabetic, anti-malarial, anti-microbial, anti-oxidant, antitumor, anti-viral and hypocholesterolemic activities which are important medicinal targets in terms of drug discovery today. Moreover, the reader’s attention is brought to focus on mushroom products and food supplements available in the market with claimed biological activities and potential human health benefits. Keywords Medicinalmushrooms . Anti-oxidant . Anti-tumor . Anti-HIV . Anti-microbial . Anti-viral . Hypocholesterolemic . Anti-diabetic . Anti-Alzheimer . Anti-malarial . Food supplementsFungal diversity 09/2013; 62(1):1-40. DOI:10.1007/s13225-013-0265-2 · 6.94 Impact Factor
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ABSTRACT: Ganoderic acids (GAs) Mk, T, S and R exhibit promising anti-tumor effect, but they are difficult to purify from Ganoderma lucidum mycelia due to the presence of numerous analogs. In this work, a novel and efficient extraction/hydrolysis method was developed for the recovery of these four GAs from the mycelia of G. lucidum. By using a 50% aqueous ethanol solution containing 50 mmol/l HCl as extractant, extraction of GAs from mycelia and conversion of analogs impurities into the products of interest could be achieved in one step. This one-pot extraction/hydrolysis process increased the yield of GA-Mk, -T, -S and -R to 242%, 389%, 189% and 420%, respectively, compared to a raw sample without hydrolysis. Simultaneous purification of these four GAs was readily achieved in a single RP-HPLC run due to the conversion of analog impurities into corresponding desired GAs, and the purity and recovery of these four GAs were over 97% and 90%, respectively. The results demonstrated that the simultaneous extraction and hydrolysis process is simple and efficient and thus can act as a useful approach for enhanced recovery of those four GAs from G. lucidum mycelia.PROCESS BIOCHEMISTRY 02/2013; 48(2):331–339. DOI:10.1016/j.procbio.2012.12.002 · 2.52 Impact Factor