Pharmacognostic Evaluation, Antioxidant Activity and Anticoagulant/coagulant Activity of Zingiber Officinale Roscoe (zingiberaceae) and Ocimum Gratissimum L. (lamiaceae): Exploring Their Potential as Nutraceuticals.

ABSTRACT There has been an increase in interest towards natural products that offer potential health benefits. Ginger (Zingiber officinale) and scent leaf (Ocimum gratissimum) are two used herbs that have long been recognized for their traditional medicinal properties. This study aimed to evaluate the characteristics and chemical composition of these plant extracts focusing on their antioxidant and anticoagulant activities with the intention of exploring their potential as nutraceuticals. The macroscopic test, phytochemical tests and chemomicroscopic tests were investigated based on standard procedures. The in vitro antioxidant and anticoagulant activities of the plants extracts were evaluated using DPPH (2,2-di(4-tert-octylphenyl)-1-picrylhydrazyl) and thrombin & prothrombin respectively. Zingiber officinale had a percentage yield of 6.71 % and Ocimum gratissimum had a yield of 3.21 %. Macroscopic evaluation showed that Zingiber officinale had dried rhizomes, with a dark grey color and its distinct aroma while Ocimum gratissimum had leaves with a pleasant scent. Both Zingiber officinale and Ocimum gratissimum displayed lignin, starch, calcium oxalate and cellulose confirming the integrity of these plants. Furthermore, phytochemical analyses revealed compounds in both plant extracts. These compounds included tannins, starch, flavonoids, alkaloids, cardiac glycosides, anthraquinones and saponins. Zingiber officinale had highest %inhibition of 86.26 % at a concentration of 500 µg/mL while Ocimum gratissimum had highest %inhibition of 83.40 % at a concentration of 500 µg/mL. The IC50 of Zingiber officinale and Ocimum gratissimum were 72.131 µg/mL and 63.156 µg/mL respectively. It is observed that Zingiber officinale causes a slight increase in the thrombin time and prothrombin time when compare to control sample (heparin), while Ocimum gratissimum does not cause an increase in the thrombin time and prothrombin time, rather it decreases it. These plants which can be used as food or part of food possess antioxidant and anticoagulant/coagulant activities and as such should be considered as nutraceuticals. Keywords: Zingiber officinale, Ocimum gratissimum, antioxidant activities, anticoagulant activities, nutraceuticals.