Biological activities of intact and degraded glucosinolates on Salmonella spp. and HaCaT and II-4 cells

Abstract

Glucosinolates, naturally existing organic compounds, are nitrogen and sulfur containing secondary metabolites found mainly in the Brassicaceae family and are responsible for the pungent taste of most cruciferous plants, such as broccoli, horseradish and cabbage. The hydrolysis of glucosinolates is catalyzed by an endogenous thioglucosidase enzyme, commonly referred to as myrosinase that coexists with these compounds. Upon tissue damage, myrosinase comes in contact with glucosinolates and hydrolyses them into a number of bioactive compounds, including isothiocyanates, thiocyanates, and nitriles. These compounds are known to exhibit biocidal activity against different micro-organisms, as well as anti-cancer effects. Glucosinolates extracted from broccoli, radish and turnip, along with their hydrolysis products were tested using the serial dilution method for their biological activity against 15 strains of Salmonella collected from different Lebanese patients. In addition, the effect of these compounds was tested on the eukaryotic HaCaT cells, an immortalized, nontumorigenic, human epidermal keratinocyte-derived cell line and II-4 cells, a malignant form of HaCaT cells. Results showed that intact and degraded glucosinolates from broccoli and radish have an antimicrobial potential against all Salmonella strains with degraded glucosinolates from broccoli being the most effective. Intact glucosinolates from turnip had an inhibitory effect against all strains. However, the degraded form showed no inhibition with the concentrations used. HaCaT and II-4 cells both showed a great decrease in percentage viability when treated with intact and degraded glucosinolates from all three plants at 10 mg ml-1 and 20 mg ml-1. However, both cell lines had similar viability profiles when tested with both intact and degraded glucosinolates.