PHYSIOLOGICAL AND BIOCHEMICAL RESPONSES OF MEDICINALLY IMPORTANT NIGELLA SATIVA PLANT IN DIFFERENT PHASES OF GERMINATION

Abstract

Nigella sativa (Kalonji, Black cumin) is an annual flowering plant, belonging to Ranunculaceae family. N. sativa has been used traditionally as spice, carminative, condiment, aromatic, stimulant, diuretic, stomachic, liver tonic and digestive. Germinating seeds are known to contain high concentrations of various metabolites of nutritional and medicinal value and several biochemical constituents and enzymes. newlineN. sativa seeds were germinated in distilled water, 2mM CdCl2 and 100mM NaCl solutions separately at 25°C and a light intensity of 100µmol m-2s-1 and a 14/10 h (day/night). The samples in various phases of germination were collected daily for 11 days till plantlet was observed. A morphological study was conducted in different phases of germination and comparison was made between seeds grown under stress. Germination-induced biochemical alterations in various biomolecules and phytochemicals were seen. The levels of expression of different enzymes and antioxidant enzymes were studied during different phases of germination. The study of secondary metabolite production during germination and the antibacterial potential of the germinating seeds were also evaluated. newlineThe results obtained showed that germination increases the nutritional and medicinal value of N. sativa seeds. Decrease in anti-nutritional and toxic metabolites such as tannins and phenols were also observed. It was seen that on 6th and 7th day of seed germination the expression of different biomolecules, activity of various enzymes was on their highest level Hence, the five/six day germinated seed of N. sativa can be seen as a potential source of drugs. newlineVery few scientific studies have been undertaken on the germination biochemistry of spices and there is not even a single report published on this aspect of N. sativa seed. No previous reports have been published for evaluating the antimicrobial potential of extracts of different germinating phases of seeds. This is the first study on the alteration on the antimicrobial potential of seeds during germination. newline