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Volume: 44 Issue: 1

  • Open Access
  • Original Article

Evaluation of in vitro antidiabetic, antioxidant, and antibacterial activities of phytochemicals from Memecylon malabaricum Cogn.

Prathap H.M., Vadlapudi Kumar, Manjunatha T., Ruksana F., Vishala E., Savitharani M.

Department of Studies in Biochemistry, Davangere University, Shivagangothri, Davangere, 577007, Karnataka, India

Corresponding author: Vadlapudi Kumar. Email: [email protected]

Year: 2024, Page: 46-51, Doi: https://doi.org/10.51248/.v44i1.4119

Received: Dec. 1, 2023 Accepted: Feb. 1, 2024 Published: May 1, 2024


Introduction and Aim: Plant secondary metabolites have been found to have antidiabetic, antioxidant, and antimicrobial properties. Memecylon malabaricum Cogn., is one of endemic plant species belonging to the melastomataceae family which can be found in western ghats, sacred groves of Dakshina Kannada and Udupi districts of Karnataka, India. This study was to assess the antidiabetic, antioxidative and antimicrobial activities of alkaloids and saponins present in the plant M. malabaricum.
Materials and Methods: Leaves of M.malabaricum were collected from forests of Western Ghats region, Shivamogga district in Karnataka, India. Alkaloids and saponins were isolated and quantified as previously described. Antidiabetic, antioxidant, and antimicrobial activities were evaluated for alkaloids and saponins of M. malabaricum leaves.
Results and Discussion: Total alkaloid content and saponin content were found to be 147.407.00mg AE/g and 170.5347 mg QE/g and respectively. IC50 of LAF and LSF for α-amylase enzyme were found to be 62.117 and 151.058 mg/ml respectively, while for α-glucosidase the LAF and LSF exhibited 30.008 and 43.872 μg/ml IC50 values respectively. At 100 μg/ml concentration, the free radical scavenging activity of LSF reached around 74% for DPPH and 40% for nitric oxide. At 100 μg/ml concentration, the scavenging activity of LAF reached around 45% for DPPH and 26% for nitric oxide. The LSF has significantly inhibited both Gram-negative Pseudomonas aeruginosa and Gram-positive Staphylococcus aureus bacteria compared to LAF.
Conclusion: Compared to saponin fraction, alkaloid fraction has shown better antidiabetic activity against both α-amylase and α-glucosidase enzymes in vitro. Saponin fraction has exhibited better antioxidant activity than the alkaloid fraction. The saponin fraction exhibited better antibacterial activity compared to the alkaloid fraction. From the results, it could be concluded that alkaloid fraction and saponin fraction of the M. malabaricum leaves could be used to manage/treat the diabetic condition, as they possess antioxidant properties.

Keywords: Memecylon malabaricum; in vitro antidiabetic activity; in vitro antioxidant activity; in vitro antibacterial activity.


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Cite this article

Prathap H.M., Vadlapudi Kumar, Manjunatha T., Ruksana F., Vishala E., Savitharani M. Evaluation of in vitro antidiabetic, antioxidant, and antibacterial activities of phytochemicals from Memecylon malabaricum Cogn. Biomedicine: 2024; 44(1): 46-51