IOSR Journal of Applied Chemistry (IOSR-JAC) e-ISSN: 2278-5736.Volume 13, Issue 5 Ser. II (May. 2020), PP 26-31 www.iosrjournals.org DOI: 10.9790/5736-1305022631 www.iosrjournals.org 26 |Page Phytochemical Analysis and Biological Assay of the Stem Bark of Pterocarpus Santalinoides in Kumasi, Ghana. Abare-Jen, L 1 ; Mensah, J.K 2 ; Borqouye, S. L 2 1 Department of Chemistry, Taraba State University, PMB 1167, Taraba State, Jalingo. Nigeria. 2 Department of Chemistry, Kwame Nkrumah University of Science and Technology, PMB, KNUST, Kumasi. Ghana. Abstract: The use of any plant as medicine is attributed to the presence of phytochemicals which are responsible for the biological activities. Pterocarpussantalinoides is a medicinal plant belonging to the family fabaceae. The stem bark extracts of the plant were evaluated for their phytochemical constituents; tested for antimicrobial activity (with Augmentin as standard) by the agar diffusion method and evaluated for their antioxidant potential by DPPH free radical scavenging and H 2 O 2 scavenging activities. Results of the phytochemical analysis revealed the presence of flavonoids, phlobatannins, tannins, glycoside, saponins, alkaloids and terpenoids in all the three extracts (ethanol, hexane, and ethyl acetate extracts); while the hexane and ethyl acetate extracts contain in addition to these, steroids. Anthraquinone was however only present in the hexane extract. Test organisms for antidiarrheal activities include Salmonella typhi, Escherichia coli, Campylobacter, and Staphylococcus aureus. The extracts showed varying degree of inhibitory activity against tested organisms. The zone of inhibition for the hexane extract range from 7 -19mm, that of ethyl acetate extract range from 9 – 13mm, while that of ethanol extract range from 9.5 – 15mm. The antioxidant activity was found to be concentration dependent. For DPPH radical scavenging, hexane extract had the highest percent scavenging value (86.16 %) comparable with that of the standard ascorbic acid (89.35%). H 2 O 2 scavenging activity of the extracts was also promising, ethanol extract had the highest value (85.55%) which was comparable to that of the standard ascorbic acid (85.93 %). The results show that the traditional use of the plant Pterocarpus santalinoides is justified especially in the treatment of diarrhea. The variety pterocarpussantalinoides in Kumasi is a promising source of antimicrobials and antioxidants due to its rich phytochemical content. Keywords: ethanolic extract, antioxidant activity, DPPH, antimicrobial activity, H 2 O 2 --------------------------------------------------------------------------------------------------------------------------------------- Date of Submission: 04-05-2020 Date of Acceptance: 18-05-2020 --------------------------------------------------------------------------------------------------------------------------------------- I. Introduction Africa has a rich history in traditional healing, especially in the use of the diverse medicinal plants available. These plants are used to treat various health conditions ranging from cough, diarrhea, headaches, fever, skin diseases, stomach upset to mention but a few. However, scientific research on the biological efficacy of most of these plants is lacking. The presence of antimicrobial compounds in plants serves as a useful area in the development of natural products that come handy in replacing the antibiotics against antibiotic resistant pathogens, and serves as a foundation for new antimicrobials. Man has grappled with numerous diseases since time immemorial, it is now widely known that free radicals are implicated as being responsible for most human degenerative diseases; as most of the diseases have been traced to uncontrollable production of free radicals, which accumulates in the body, and causes oxidative stress 1 , this leads to diseases when its abundance becomes unbalanced. Artificial antioxidants such as butylated hydroxyl toluene (BHT), tertiary butylated hydroquinone (TBH), butylatedhydroxyl anisole (BHA) and gallic acid esters are being implicated in negative health effects, thus, there is a strict restriction placed on their application 2 . There is now a trend to substitute them with naturally occurring antioxidants 3 . Herbal remedies play an important role in maintaining the health of man. It is common knowledge today that the majority of the world uses herbal remedies; this is also approved by world health organization as safe alternative to synthetic drugs due to the fact that they have stood the test of time with regards to safety, efficacy, cultural acceptance and minimal adverse effect. According to world health organization (WHO), about 21,000 plants have been used for medicinal purposes and 80% of the world relies on traditional medicine 4 . The medicinal potentials of these plants lie in the presence of some secondary metabolites, collectively called phytochemicals. These phytochemicals have great potentials as herbal medicines or as precursors for modern medicines.