@article {1300, title = {In vitro Antioxidant and Antidiabetic Potential of Crude Extracts from the Seed Coat and Fruit Pulp of Strychnos madagascariensis}, journal = {Pharmacognosy Journal}, volume = {12}, year = {2020}, month = {November 2020}, pages = {1504-1511}, type = {Original Article}, chapter = {1504}, abstract = {

Diabetes mellitus remains a global health issue despite the advance in orthodox medicine. This study investigated the in vitro antioxidant and antidiabetic potential of crude extracts from the seed coat and pulp of Strychnos madagascariensis. The phytochemical screening was carried out using standard protocols. Different extracts were prepared from the fruit parts by maceration using methanol, n-hexane, ethyl acetate, and water for antioxidant and antidiabetic assays, and their percentage yield was calculated. The antioxidant potential of the extracts was determined using 2,2{\textquoteright}-azino-bis (3-ethylbenzothiazoline-6-sulphonic acid (ABTS) and 2{\textquoteright}2- diphenyl-1-picrylhydrazyl (DPPH). Antidiabetic activities of the extracts were investigated using α-amylase, α-glucosidase, and pancreatic lipase assays. Terpenoids, alkaloids and cardiac glycosides were present in both the fruit parts. However, saponin present in the fruit pulp was absent in the seed coat (testa). The percentage yields are as follows; water \> ethyl acetate \> hexane \> methanol (seed coat) and methanol \> water \> ethyl acetate \> hexane (fruit pulp), respectively. The crude extracts scavenged ABTS and DPPH radicals in different degrees. The aqueous extract of the pulp and seed coat (testa) showed significant (P \< 0.05) higher scavenging activity against ABTS (IC50; 0.012 and 0.006 mg/ml) and DPPH (IC50; 0.06 mg/ml and 0.064 mg/ml) radicals than other extracts. The crude extracts inhibited α-amylase, α-glucosidase, and pancreatic lipase. The aqueous and methanol extracts of the fruit parts showed better amylase inhibitory activity than other extracts. The aqueous extract of the seed coat (IC50; 0.0785 mg/ml) showed the highest glucosidase inhibitory activity. In addition, methanol extract of the seed coat (IC50; 0.069 mg/ml) exhibited the highest inhibitory activity on pancreatic lipase compared to the extracts in other solvents. Hence, the aqueous and methanol crude extracts of Strychnos madagascariensis seed coat and fruit pulp could be used in the preparation of nutraceutical products for managing diabetic mellitus.

}, keywords = {Alkaloids, Diabetes, Hyperglycaemia, Hyperlipidaemia, Phytochemicals}, doi = {10.5530/pj.2020.12.206}, author = {Michael Osawemi Oboh and Foluso Oluwagbemiga Osunsanmi and Godfrey Elijah Zharare and Rebamang Anthony Mosa and Michael Chukwuka Ojo and Andrew Rowland Opoku} } @article {923, title = {Phytochemical Constituents and Antioxidant Potential of Crude Extracts from Lippia Javanica (Burm.f.) Spreng Leaves}, journal = {Pharmacognosy Journal}, volume = {11}, year = {2019}, month = {July 2019}, pages = {803-807}, type = {Original Article}, chapter = {803}, abstract = {

Background: Oxidative stress is implicated in most life threaten diseases. Objectives: This study evaluated the phytochemical constituents and antioxidant activity of Lippia javanica{\textquoteright}s crude extracts. Methods: Phytochemical screening was carried out on pulverized Lippia javanica leaves using standard protocols. Crude extracts were prepared using various solvents (hexane, acetone, ethylacetate, methanol, dichloromethane respectively), and percentage yields calculated. The antioxidant activities of crude extracts were monitored with DPPH, ABTS and nitric oxide (NO) radicals using spectra techniques. Results: The phytochemical presents in Lippia javanica were tannin, flavonoids, terpenoids, alkaloids and phenols. Percentage yield increased in order; Acetone \> Methanol, \> Dichloromethane \> Ethyl-acetate \> Hexane. All the crude extracts showed differ degrees of antioxidant potential as evidence by significantly (P \< 0.05) scavenging DPPH, ABTS and NO radicals, Acetone crude extract showed the lowest IC50 (2.22 {\texttimes} 10-3 and 2.42 {\texttimes} 10-3 mg/ml) toward DPPH and ABTS radical respectively in comparison to other crude extracts, and the positive controls (Ascorbic acid and Butylated hydroxyl anisole), Hexane crude extract showed the lowest IC50 (3.95 {\texttimes} 10-1 mg/ml) toward NO radical compared with other treatments. Conclusion: Therefore, this study proves that Lippia javanica crude extracts are good source of natural antioxidants in alleviating oxidative stress diseases. Isolation of bioactive compounds from crude extracts are desirable for future studies.

}, keywords = {ABTS, Antioxidants, DPPH, Lippia Javanica, Phytochemicals}, doi = {10.5530/pj.2019.11.128}, author = {Foluso Oluwagbemiga Osunsanmi and Godfrey Elijah Zharare and Andy Rowland Opoku} }