Abstract:
Plants are commonly used in the treatment of diseases in complementary, alternative
healthcare and medical practices. There is a varied diversity of compounds particularly
secondary metabolites extracted from plants and researches have shown that these
compounds have anticancer, antibacterial and antidiabetic activities. No comparative
laboratory studies and scientific approach of efficacy related to phytochemicals found in
seeds of medicinal plants are yet reported. The aim of this study is qualitative and
quantitative analysis of phytochemicals present in seeds extracts of four medicinal plants
such as Syzygium cumini, Brassica alba, Trigonella foenum and Nigella sativa used in the
treatment of diabetic mellitus in Sri Lanka.Seeds of above medicinal plants were
collected and ethanolic extraction was carried. The qualitative phytochemicals were
screened using generally accepted laboratory techniques. Flavonoids, Tannins,
Phenols, Alkaloids, Saponins found in the seed extracts of all plants. Terpenoids,
Anthraquinones and Quinones were only found in Syzygium cumini and Nigella sativa.
Glycosides was found only in Syzygium cumini. Syzygium cumini contains all the
phytochemicals examined and found to a greater extent than other plants.The quantitative
analysis was carried out for Phenols, Tannins, Flavonoids and Alkaloids. Tannin was
found in all seed extracts examined with the highest quantities obtained in Syzygium
cumini (34.04 µg/ml) and Brassica alba (33.04 µg/ml). Syzygium cuminiseeds which
contain exceptionally highest phenolic content (416.01 µg/ml). Highest flavonoid content
found in Syzygium cumini(527.77µg/ml) followed by Trigonella foenum (194.66 µg/ml).
Highest alkaloid content was found in Syzygium cumini(81.07µg/ml) and the lowest
found in Nigella sativa (22.12 µg/ml). This study revealed that ethanolic extracts of seeds
of all plant species contain basic phytochemicals. Quantitative phytochemical analysis
showed that Syzygium cumini is richer with important specific phytochemicals. The use
of each medicinal plant, especially Syzygium cumini, can be used in the traditional system
of medicine and to prepare ready to use functional products using seeds.
