Analysis of trace heavy metals and volatile chemical compounds of Lepidium sativum using atomic absorption spectroscopy, gas chromatography-mass spectrometric and fourier-transform infrared spectroscopy.

The aims of present study were to determine five trace heavy metals and screen the antimicrobial activities of methanolic seed extract of Lepidium sativum against bacterial strains. Elements content in tested medicinal plant were 39 +/- 1.20 ppm, 6.5 +/- 0.17 ppm, 28.29 +/- 0.23 ppm, 0.46 +/- 0.03 ppm and 2.98 +/- 0.11 ppm for Fe, Zn, Mg, Co and Pb respectively. Plants were extracted with methanol and tested for their antimicrobial activity by disc diffusion method against eleven bacterial strains Salmonella typhi, Streptococcus pneumonia, Pseudomonas eurogenosa, Staphylococcus epidermidis, Escherichia coli, Bacillus subtilis, Proteus mirabilis, Streptococcus pyogenes, Staphylococcus aureus, Streptococcus faecalis, Klebsiella pneumonia and fourteen bacterial strains Aspergillus niger, Aspergillus terreus, Aspergillus flavus, Aspergillus fumigatus, Candida albicans, Saccharomyces cerevisiae, Fusarium sp., Microsporum canis, Streptococcus faecalis, Mucor sp., Penicillium expansum, Trichoderma viride, Trichoderma horzianum and Trichophyton mentagrophytes. Forty six bioactive phytochemical compounds were identified in the methanolic extract of Lepidium sativum. The identification of phytochemical compounds is based on the peak area, retention time molecular weight, molecular formula, MS Fragment ions and Pharmacological actions. Lepidium sativum was highly active against Aspergillus flavus (7.01 +/- 0.11). Methanolic extract of bioactive compounds was assayed for in vitro antibacterial activity and the diameters of inhibition zones ranged from 6.03 +/- 0.27 to 0.04 +/- 0.01 mm for all treatments. It was concluded from this study that methanolic extract has prominent activities against most of the bacterial, yeast and fungal strains.