Chemical Composition, Antioxidant Activity and Cytocompatibility of Polyphenolic Compounds Extracted from Food Industry Apple Waste: Potential in Biomedical Application.

Apple pomace (AP) from the food industry is a mixture of different fractions containing bioactive polyphenolic compounds. This study provides a systematic approach toward the recovery and evaluation of the physiochemical and biological properties of polyphenolic compounds from AP. We studied subcritical water extraction (SCW) and solvent extraction with ethanol from four different AP fractions of pulp, peel, seed, core, and stem (A), peel (B), seed and core (C), and pulp and peel (D). The subcritical water method at the optimum condition resulted in total polyphenolic compounds (TPC) of 39.08 ± 1.10 mg GAE per g of AP on a dry basis compared to the ethanol extraction with TPC content of 10.78 ± 0.94 mg GAE/g db. Phloridzin, chlorogenic acid, and quercetin were the main identified polyphenolics in the AP fractions using HPLC. DPPH radical scavenging activity of fraction B and subcritical water (SW) extracts showed comparable activity to ascorbic acid while all ethanolic extracts were cytocompatible toward human fibroblast (3T3-L1) and salivary gland acinar cells (NS-SV-AC). Our results indicated that AP is a rich source of polyphenolics with the potential for biomedical applications.

Potent antiproliferative cembrenoids accumulate in tobacco upon infection with Rhodococcus fascians and trigger unusual microtubule dynamics in human glioblastoma cells.

AIMS: Though plant metabolic changes are known to occur during interactions with bacteria, these were rarely challenged for pharmacologically active compounds suitable for further drug development. Here, the occurrence of specific chemicals with antiproliferative activity against human cancer cell lines was evidenced in hyperplasia (leafy galls) induced when plants interact with particular phytopathogens, such as the Actinomycete Rhodococcus fascians. METHODS: We examined leafy galls fraction F3.1.1 on cell proliferation, cell division and cytoskeletal disorganization of human cancer cell lines using time-lapse videomicroscopy imaging, combined with flow cytometry and immunofluorescence analysis. We determined the F3.1.1-fraction composition by gas chromatography coupled to mass spectrometry. RESULTS: The leafy galls induced on tobacco by R. fascians yielded fraction F3.1.1 which inhibited proliferation of glioblastoma U373 cells with an IC50 of 4.5 µg/mL, F.3.1.1 was shown to increase cell division duration, cause nuclear morphological deformations and cell enlargement, and, at higher concentrations, karyokinesis defects leading to polyploidization and apoptosis. F3.1.1 consisted of a mixture of isomers belonging to the cembrenoids. The cellular defects induced by F3.1.1 were caused by a peculiar cytoskeletal disorganization, with the occurrence of fragmented tubulin and strongly organized microtubule aggregates within the same cell. Colchicine, paclitaxel, and cembrene also affected U373 cell proliferation and karyokinesis, but the induced microtubule rearrangement was very different from that provoked by F3.1.1. Altogether our data indicate that the cembrenoid isomers in F3.1.1 have a unique mode of action and are able to simultaneously modulate microtubule polymerization and stability.

In vitro antiprotozoal, antimicrobial and antitumor activity of Pavetta crassipes K. Schum leaf extracts.

AIM OF THE STUDY: To study the potential benefit of the traditional medicinal plant Pavetta crassipes K. Schum (Rubiaceae), which is widely distributed throughout West Africa, the methanol and dichloromethane extracts were isolated from the plant leaves to determine if they exhibited antiprotozoal, antibacterial, antifungal or antitumor activity in vitro. MATERIALS AND METHODS: The methanol and dichloromethane extracts and their specific fractions were obtained using bioassay-guided fractionation and investigated for antiproliferative activity in vitro in microorganisms (Staphylococcus aureus, Escherichia coli and Candida albicans), protozoans (Trypanosoma cruzi, Trypanosoma brucei, Leishmania infantum and Plasmodium falciparum), and cancer (U373, PC3, MXT and A549) and normal cell lines (NHDF and MRC-5). RESULTS: Most of the alkaloid fractions investigated exhibited antiproliferative activity in all the cancer cell lines, microorganisms and protozoans studied. CONCLUSIONS: The benefit of Pavetta crassipes as a traditional medicinal remedy was confirmed using antiprotozoal and cytotoxicity assays in vitro. These analyses revealed that the components present in the alkaloid extract of Pavetta crassipes are responsible for its antiprotozoal and cytotoxic efficacy.

In vitro anticancer potential of tree extracts from the Walloon Region forest.

Forty-eight extracts from 16 common Belgian trees from the Walloon Region forest were evaluated for in vitro growth inhibitory activity against the human LoVo colon cancer, PC3 prostate cancer, and U373 glioblastoma cell lines. Our study was performed with the aim of selecting plant candidates in order to later isolate new anticancer compounds from an easily affordable tree material. Extracts from Alnus glutinosa (stem bark), Carpinus betulus (leaves and stem bark), Castanea sativa (stem bark), Fagus sylvatica (leaves), Ilex aquifolium (leaves), Larix decidua (leaves), Quercus petraea (stem bark), and Quercus robur (leaves) showed for the first time potent in vitro growth inhibitory activity and could become easily affordable sources of potential new anticancer agents. Root extracts from Robinia pseudoacacia, already known for containing cytotoxic lectins, also showed interesting activity.