Bioassay-guided preparation of antioxidant, anti-inflammatory active fraction from crabapples (Malus prunifolia (Willd.) Borkh.).

The aim of current study was to optimize the extraction process and purification of main components (MC) to obtain high antioxidant, anti-inflammatory effective fractions from crabapple (Malus prunifolia (Willd.) Borkh.). The effects of three variables including ethanol concentration A1, solid-liquid ratio A2, extraction temperature A3 were investigated and optimized by response surface methodology (RSM) coupled with Box-Behnken design (BBD). The adsorption/desorption characteristics of MC on the five types of macroporous resins were investigated. According to batch adsorption test, HPD-300 resins were selected for kinetics. The adsorption mechanism showed that the process was appropriate by pseudo-second-order kinetics model, and purification parameters of MC were optimized through adsorption/desorption experiments with the column packed by HPD-300 resin. The effective fractions were obviously superior to other fractions according to DPPH, ABTS, COX-2 and 15-LOX radical scavenging. This work implies that the purified active fraction with high contents of antioxidants and anti-inflammatory compounds from crabapple might be potential source for natural products and food industries.

Phenolic Compounds and Bioactivities from Pomegranate (Punica granatum L.) Peels.

Pomegranate peels, which are normally processed as the main byproduct of pomegranate juice production, are worthy of being researched and utilized for the aim of economic and environmental benefits. In a phytochemical investigation of the peels of Punica granatum L., 10 phenolic compounds containing a common hexahydroxy diphenol moiety were isolated. Three of them were identified for the first time and named as pomegranatins A-C, and from the other seven known ones, two of them were obtained from pomegranate peels for the first time. Their structures were determined via extensive spectroscopic analysis. Besides, for the sake of preliminarily comprehending their biological activities, in vitro antimicrobial, antioxidant, as well as antitumor assays were detected. In the DPPH antioxidant assay, six compounds presented significant free radical scavenging ability. Two compounds exhibited moderate antimicrobial activities against Candida albicans; one compound could inhibit the proliferation of both C. albicans and Escherichia coli within limits. Four compounds possessed weak antitumor activity toward the Hela cell line without taking into account the bioavailability of ellagitannins. Overall, these results provided further information on the structural diversity of bioactive compounds present in pomegranate peels, as well as on their biological activities.