Plants' bioactive chemicals have been utilized throughout human history as supplements and medicines to support the body's natural physiological processes. When their function is discovered, many substances are added for medical uses. Herbs are known to contain a variety of organic substances. These crucial herbs are the main ingredients in many pharmaceutical and healthcare products. Traditional folk medical practices offer essential information for the extraction and creation of numerous medications and activities as well. The production of a few highly active pharmaceuticals is justified by the extraction and characterization of a variety of bioactive chemicals from green factories. This study uses quantitative analysis of ethyl acetate, ethanol, n-hexane, chloroform and aqueous extract along with established methodologies to assess the phytochemicals. Alkaloids, flavonoids, reducing sugars, proteins, amino acids, saponins, tannins, terpenoids and glycosides were discovered in the quantification and phytochemical screening results. Due to the presence of several phytochemical substances, the entire plant of Psychotria octosulcata W. A. Talbot demonstrated a diversity of medicinal potential. The cytotoxicity activity of the plant extracts was predicted using brine shrimp lethality assay (BSLA). The results showed that the shrimp in the ethanolic extract of Psychotria octosulcata W. A. Talbot are extremely hazardous in higher concentrations. Only 10 shrimps are discovered to be lethal at lowest concentrations even after 24 h. This can be due to the presence of bioactive substances. © 2024 Elsevier B.V., All rights reserved.