Antioxidant and Antimicrobial Properties of Fruiting Body and Submerged Mycelium of Medicinal Mushroom Phellinus robiniae (Agaricomycetes).

This study was conducted to evaluate extraction yield, antioxidant content, antioxidant capacity and antibacterial activity of extracts obtained from submerged mycelium (ME) and fruiting body (FBE) of Phellinus robiniae NTH-PR1. The results showed that yields of ME and FBE reached 14.84 ± 0.63 and 18.89 ± 0.86%, respectively. TPSC, TPC, and TFC were present in both mycelium and fruiting body, and the more contents of them were found in fruiting body. The concentrations of TPSC, TPC and TFC in ME and FBE were 17.61 ± 0.67 and 21.56 ± 0.89 mg GE g-1, 9.31 ± 0.45 and 12.14 ± 0.56 mg QAE g-1, and 8.91 ± 0.53 and 9.04 ± 0.74 mg QE g-1, respectively. EC50 values for DPPH radical scavenging revealed FBE (260.62 ± 3.33 µg mL-1) was more effective than ME (298.21 ± 3.61 µg mL-1). EC50 values for ferrous ion chelating in ME and FBE were 411.87 ± 7.27 and 432.39 ± 2.23 µg mL-1, respectively. Thus, both extracts were able to inhibit Gram-positive and Gram-negative pathogenic bacterial strains, at concentrations ranging in 25-100 mg mL-1 of ME and 18.75-75 mg mL-1 of FBE for Gram-positive bacteria; ranging in 75-100 mg mL-1 of ME and 50-75 of FBE for Gram-negative bacteria. Overall submerged mycelial biomass and fruiting bodies of Ph. robiniae NTH-PR1 can be considered as useful natural sources for development of functional food, pharmaceuticals and cosmetic products or cosmeceuticals.

Pregnane glycosides from the leaves of Dregea volubilis and their α-glucosidase and α-amylase inhibitory activities.

Three new pregnane glycosides, drevoluosides O-Q (1-3) along with five known volubiloside C (4), dreageoside A11 (5), 17ß-marsdenin (6), stavaroside H (7), and hoyacarnoside G (8) were isolated from the methanol extract of the Dregea volubilis leaves. Their structures were elucidated by chemical and spectroscopic methods. Compounds 6-8 showed significant anti α-glucosidase activity with the inhibitory percentages ranging from 32.6 to 47.1% at the concentration of 200 µM. Compound 3 showed significant inhibitory α-amylase activity with IC50 value of 51.3 ± 2.1 µM.