Phytochemicals of black bean seed coats: isolation, structure elucidation, and their antiproliferative and antioxidative activities

Isolated compounds from black bean inhibit the classical pathway of the complement

The present study evaluated the anticomplement effects from isolated compounds of black bean in classical pathway complement system. Using column chromatograph, four compounds kaempferol 3-O-β-D-glucopyranoside (1), kaempferol 5-O-β-D-glucopyranoside (2), 3-O-[α-L-rhamnopyranosyl(1-2)-β-D-glucopyranosyl(1-2)-β-D-glucuronopyranosyl]olean-12-en-3β,22β,24-triol (3) and 3-O-[β-D-glucopyranosyl(1-2)-β-D-galactopyranosyl(1-2)-β-D-glucuronopyranosyl]olean-12-en-3β,22β,24-triol (4) were isolated and evaluated for in vitro anticomplement activity. 3 showed inhibitory activity against complement system with 50% inhibitory concentrations (IC(50)) values of 98.2 μg/ml. This is the first report of anticomplement activity of isolated compounds from black bean.

Influence of potent antioxidant leguminosae family plant extracts on growth and antioxidant defense system of Hep2 cancer cell line

Legumes are considered to be a very good source of polyphenolic compounds that may act as chemopreventive agents, especially by their antioxidant properties. However, many of the chemopreventive properties may depend on the concentrations of the phytochemical compounds because potent antioxidant polyphenolic compounds may have pro-oxidant properties and negatively affect cell growth and viability. Thus, the aim of the present study was to assess the possible effect of two potent antioxidant Greek Leguminosae family plant extracts on the growth of a specific cancer cell line and its antioxidant defense cell system. Aqueous extracts of aerial parts of Lathyrus laxiflorus and Phaseolus vulgaris plants were initially examined for their cytotoxicity on the Hep2 cancer cell line at concentrations that possess potent antioxidant properties (100, 400, and 800 microg/mL). After a 24-hour incubation with the extracts, only L. laxiflorus plant extract exhibited the ability to inhibit the cell growth at 400 and 800 microg/mL by 57% and 74%, respectively, whereas P. vulgaris extract had no effect on cell growth at any of the tested concentrations. Noncytotoxic concentrations, 100 microg/mL L. laxiflorus and 800 microg/mL P. vulgaris extract, were used for 2-, 12-, and 24-hour incubation of the cells. The influence of the extracts on the antioxidant defense system of the cells was assessed by measuring the total antioxidant capacity (TAC) of the cells, the catalase (CAT) activity, and the concentrations of reduced glutathione, the oxidized form of glutathione, and thiobarbituric-reactive substances (TBARS) in all times of incubation with the cells. From the results obtained, it seems that only L. laxiflorus extract induces oxidative stress in the cells by reducing TAC and CAT activity and by inducing TBARS, especially with 2 and 12 hours of incubation. P. vulgaris extract reduced only TAC at 2 hours of incubation, indicating also a mild induction of oxidative stress. These results imply that potent antioxidant extracts, beyond a critical concentration, may induce oxidative stress even with no apparent cytotoxicity in cells.

Triterpenoids

This review covers the isolation and structure determination of triterpenoids including squalene derivatives, protostanes, lanostanes, holostanes, cycloartanes, dammaranes, euphanes, tirucallanes, tetranortriterpenoids, lupanes, oleananes, friedelanes, ursanes, hopanes, isomalabaricanes and saponins; 574 references are cited.

Effect of different cooking conditions on phenolic compounds and antioxidant capacity of some selected Brazilian bean (Phaseolus vulgaris L.) cultivars

The effects of different cooking conditions such as soaking, atmospheric (100 degrees C) or pressure boiling (121 degrees C), and draining of cooking water following thermal treatment on phenolic compounds and the DPPH radical scavenging capacity from two selected Brazilian bean cultivars (black and yellow-brown seed coat color) were investigated using a factorial design (2(3)). Factors that significantly reduced the total phenolic contents and antioxidant capacity in both cultivars were the soaking and draining stage. Independent of cooking temperature, total phenolics and antioxidant capacities were enhanced in treatments without soaking and where cooking water was not discarded, and this was likely linked to an increase of specific phenolic compounds detected by high performance liquid chromatography such as flavonols and free phenolic acids in both cultivars. Cooking of beans either at 100 or 121 degrees C, without a soaking stage and keeping the cooking water, would be recommendable for retaining antioxidant phenolic compounds.

Triterpenoic acids of Prunella vulgaris var. lilacina and their cytotoxic activities in vitro

The column chromatographic separation of the MeOH extract from the aerial parts of Prunella vulgaris var. lilacina Nakai led to the isolation of fifteen triterpenoic acids (2-6, 9-13, 16-20), four flavonoids (14, 21-23), four phenolics (7, 8, 15, 24), and a diterpene (1). Their structures were determined by spectroscopic methods to be trans-phytol (1), oleanic acid (2) ursolic acid (3), 2alpha,3alpha,19alpha-trihydroxyurs-12en-28oic acid (4), 2alpha,3alpha-dihydroxyurs-12en-28oic acid (5), maslinic acid (6), caffeic acid (7), phydroxy cinnamic acid (8), 2alpha,3alpha,19alpha,23-tetrahydroxyurs-12en-28oic acid (9), 2alpha,3alpha,23-trihydroxyurs-12en-28oic acid (10), 2alpha,3beta-dihydroxyurs-12en-28oic acid (11), 2alpha,3beta,24-trihydroxyolea-12en-28oic acid (12), (12R, 13S)-2alpha,3alpha,24,trihydroxy-12,13-cyclo-taraxer-14-en-28oic acid (13), quercertin 3-O-beta-D-glucopyranoside (14), rosmarinic acid (15), 2alpha,3alpha,24-trihydroxyurs-12,20(30)-dien-28oic acid (16), 2alpha,3alpha,24-trihydroxyolea-12en-28oic acid (17), 2alpha,3beta,19alpha,24-tetrahydroxyurs-12en-28oic acid 28-O-Dglucopyranoside (18), 2alpha,3alpha,19alpha,24-tetrahydroxyurs-12en-28oic acid 28-O-D-glucopyranoside (19), prunvuloside A (20), kaempferol 3-O-alpha-L-rhamnopyranosyl(1-->6)-beta-D-glucopranoside (21), kaempferol 3-O-beta-D-glucopyranoside (22), quercertin 3-O-alpha-L-rhamnopyranosyl(1-->6)-beta-D-glucopyranoside (23), and 2-hydroxy-3-(3',4'-dihydroxyphenly)propanoic acid (24). Compounds 1, 8-12, 17, 21, 23, and 24 were isolated from this plant source for the first time. The isolated compounds were evaluated for their cytotoxicity against A549, SK-OV-3, SK-MEL-2, and HCT15 cells in vitro using the sulforhodamin B bioassay (SRB) method. Compound 3 exhibited moderate cytotoxic activity against A549, SK-OV-3, SK-MEL-2, and HCT15 cells, with ED(50) values of 3.71, 3.65, 13.62, and 5.44 microM, respectively.

Terpenoids and breast cancer chemoprevention

Cancer chemoprevention is defined as the use of natural or synthetic agents that reverse, suppress or arrest carcinogenic and/or malignant phenotype progression towards invasive cancer. Phytochemicals obtained from vegetables, fruits, spices, herbs and medicinal plants, such as terpenoids, carotenoids, flavanoids, phenolic compounds, and other groups of compounds have shown promise in suppressing experimental carcinogenesis in various organs. Recent studies have indicated that mechanisms underlying chemopreventive action may include combinations of anti-oxidant, anti-inflammatory, immune-enhancing, and anti-hormone effects. Further, modification of drug-metabolizing enzymes, and influences on cell cycling and differentiation, induction of apoptosis, and suppression of proliferation and angiogenesis that play a role in the initiation and secondary modification of neoplastic development, have also been under investigation as possible mechanisms. This review will highlight the biological effects of terpenoids as chemopreventive agents on breast epithelial carcinogenesis, and the utility of intermediate biomarkers as indicators of premalignancy. Selected breast chemoprevention trials are discussed with a focus on strategies for trial design, and clinical outcomes. Future directions in the field of chemoprevention are proposed based on recently acquired mechanistic insights into breast carcinogenesis.

Antiradical capacity and induction of apoptosis on HeLa cells by a Phaseolus vulgaris extract

Jamapa bean is a black Phaseolus vulgaris variety rich in condensed tannins, anthocyanins and flavonols with interesting biological activities. The objective of this work was to evaluate the antiradical capacity (ARC) of a Jamapa bean methanolic extract (BME) and some of the proanthocyanidin-rich fractions derived from it, using the 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay. The effect of the BME on some proteins involved in apoptosis on HeLa cells was also evaluated. A strong correlation between proanthocyanidin concentration in BME and antiradical capacity was found, suggesting that these compounds contribute significantly to antiradical activity. BME was a better radical scavenger than butylated hydroxytoluene (45.6 and 33.9% ARC at 400 microM, respectively). Two proanthocyanidin-rich fractions obtained after a preliminary separation of the BME using Toyopearl (TP4 and TP6) exhibited a higher antiradical activity than the parent extract. The treatment of HeLa cells with 35 microg BME/ml/24 h increased the expression of Bax and Caspase-3, pro-apoptotic proteins (6.13 and 1.2 times for Caspase-3 and Bax, respectively). The mechanism of action of some proteins involved in apoptosis was also evaluated, and the results suggest that black Jamapa bean could be an important source of polyphenolic compounds with potential biological use as antioxidant and anticancer agents.