@article {2520, title = {Zinc Oxide Nanoparticle Green Synthesis Using Black Cumin Seed Aqueous Extract: Its Characterization and in vitro Anti- Hyperglycaemic Properties}, journal = {Pharmacognosy Journal}, volume = {17}, year = {2025}, month = {August 2025}, pages = {434-437}, type = {Original Article}, chapter = {434}, abstract = {

Introduction: α-Amylase and α-glucosidase are carbohydrate metabolizing enzymes that are known to be involved in postprandial hyperglycaemia in diabetic patients. Objective: In a bid to source potent inhibitors of these enzymes, the study synthesized zinc oxide nanoparticles and evaluated the in vitro anti-hyperglycaemic activity. Materials and Methods: The seed aqueous extract of black Cumin (BC) was used as a capping and/or reducing agent to synthesize ZnO NPs from zinc acetate precursor. The BC-ZnONPs were characterized by microscopy (FESEM and HRTEM) and spectroscopy (UV-Vis and EDX) methods. In vitro anti-hyperglycaemic evaluation was based on α-amylase and α-glucosidase inhibition assays. Results: The BC-ZnONPs showed a spherical-to-cubical shape with a 10-50 nm size range. The UV-Vis absorption peaks at 387 and 415 nm suggest the formation of biogenic ZnO NPs. The EDX spectrum revealed 68.92\% and 27.49\% weight compositions of Zn and O, respectively, to further substantiate ZnO nanoparticle synthesis. The BC-ZnONPs showed notable anti-hyperglycaemic properties with IC50 of 87.72{\textpm}5.13 and 124.21{\textpm}15.20 μg/mL against α-amylase and α-glucosidase, respectively. Conclusion: Black Cumin seed extract was a useful biogenic material for synthesizing ZnO NPs. The BCZnONPs showed promising anti-hyperglycaemic properties based on the notable inhibitory activities against α-amylase and α-glucosidase enzymes. Future work may include evaluating the synergistic effects of black Cumin metabolites and ZnONPs, as well as determining the in vivo toxicity profile for safety considerations.

}, keywords = {Anti-Hyperglycaemia, Black cumin, ZnO Nanoparticles, α-amylase, α-glucosidase}, doi = {10.5530/pj.2025.17.54}, author = {Ayodeji Oluwabunmi Oriola and Pallab Kar} } @article {540, title = {Antioxidative Properties of Blighia sapida K.D. Koenig Stem Bark Extract and Inhibitory Effects on Carbohydrate Hydrolyzing Enzymes Associated with Non-Insulin Dependent Diabetes Mellitus}, journal = {Pharmacognosy Journal}, volume = {10}, year = {2018}, month = {January 2018}, pages = {376-383}, type = {Original Article}, chapter = {376}, abstract = {

Background and Aim: In Africa, the fruit, seed, leaf, and stem of Blighia sapida K.D. Koenig are used as remedy for a range of diseases. This study characterized the phytochemicals, assessed the antioxidant and inhibitory properties of the stem bark of Blighia sapida. Materials and Methods: Samples were consecutively extracted using ethanol solvent and investigated for phenol content, DPPH radical scavenging abilities, iron chelation, reducing power, \α-amylase and \α-glucosidase activities as markers of in vitro anti-diabetic activities. Phytochemicals were analyzed using gas chromatography-mass spectrometry (GC-MS) analysis. Results: The extract had radical scavenging capabilities, iron chelation and reducing power. Furthermore, the results reveal the extract had considerably high \α-glucosidase and \α- amylase inhibitory activities as the concentration increases with IC50 values of 4.17 \± 0.24 mg/mL and 5.30 \± 1.25 mg/mL, respectively. Enzyme kinetic studies indicated that the extract displayed uncompetitive inhibitor for \α-glucosidase and was a competitive inhibitor of \α-amylase. The ethanolic extract is rich in several aromatic phenolic compounds and long chain aliphatic acids. Conclusion: These results reveal the bark possessed antioxidant as well as \α -glucosidase and \α -amylase inhibitory activities.

}, keywords = {Antidiabetic, antioxidant activity, Blighia sapida K D Koenig, α-amylase, α-glucosidase}, doi = {10.5530/pj.2018.2.63}, url = {http://fulltxt.org/article/494}, author = {Oluwafemi Adeleke Ojo and Basiru Olaitan Ajiboye and Oluwatosin Debbie Imiere and Oluwatosin Adeyonu and Israel Olayide and Adewale Fadaka} } @article {772, title = {Inhibitory Actions of Lagerstroemia speciosa (L.) Pers. Aqueous and Ethanolic Leaf Extracts against Carbohydrate-digesting Enzymes}, journal = {Pharmacognosy Journal}, volume = {10}, year = {2018}, month = {November 2018}, pages = {s113-s118}, type = {Original Article}, chapter = {s113}, abstract = {

Context: The leaves of Lagerstroemia speciosa (L.) Pers. (banaba) have been consumed traditionally in several Southeast Asian countries for the treatment of diabetes mellitus. The plasma glucose lowering actions of this medicinal plant were proposed to be linked with several mechanisms of action. However, its inhibitory actions against \α-amylase and \α-glucosidase, which play a major role in the regulation of postprandial plasma glucose, have not been clearly established. Aims: This study thus aimed to investigate the effects of Lagerstroemia speciosa (L.) Pers. aqueous and ethanolic leaf extracts (LSA and LSE extracts, respectively) on in vitro carbohydrate-digesting enzyme activities and enzyme kinetics. Settings and Design: In vitro carbohydrate-digesting enzyme activity assay. Materials and Methods: The activities of \α-amylase and \α-glucosidase were indicated by the amounts of maltose and p-nitrophenol generated in the reactions, respectively. Statistical analysis used: The data were analysed by using one-way ANOVA, followed by Bonferroni post-hoc test. Results: The LSA extract significantly inhibited both \α-amylase and \α-glucosidase enzymes with the IC50s of 1.21\±0.16 and 49.71\±0.86 \μg/mL, respectively. Meanwhile, the LSE extract selectively inhibited \α-amylase activity (IC50 = 22.21\±4.00 \μg/mL) with no apparent inhibition against \α-glucosidase activity. Both LSA and LSE extracts inhibited \α-amylase enzyme in a mixed inhibition manner whilst the LSA extract also acted as a mixed inhibitor against \α-glucosidase enzyme. The extracts possessed higher binding affinities toward the enzymes, indicated by the lower Ki values, when compared to acarbose (positive control). Conclusion: These results suggest the potential use of the extracts for a control of postprandial plasma glucose.

}, keywords = {Diabetes mellitus, Lagerstroemia speciosa (L.) Pers., α-amylase, α-glucosidase}, doi = {10.5530/pj.2018.6s.22}, author = {Wanwisa Khunawattanakul and Passakorn Boonma and Ronnarit Kampetch and Achida Jaruchotikamol and Benjamart Cushnie and Sakulrat Rattanakiat and Pawitra Pulbutr} }