Total Phenolic Content and Antioxidant Activities of Bitter Gourd (Momordica Charanta) Pith Extract

Oxidative stress has been proven to have a pathological role in many types of chronic diseases such as diabetes, heart disease and cancer. Bitter gourd (Momordica charantia), which is a powerful nutrient-dense plant composed of a complex array of beneficial compounds have long known as traditional therapeutics associated with its antioxidant properties. Numerous study have reported the total phenolic content and antioxidant activity of Momordica charantia yet only focused on the fruits. seed and leaves extracts. Pith, on the other hand, was treated as a cooking waste for all this while. Hence, this study was conducted to determine the total phenolic content and antioxidant of Momordica charantia pith extract and examine the effect of solvent used on the variation of phenolic compounds and antioxidant activity. The sample was extracted using 3 different solvents - distilled water, methanol and petroleum ether. Folin-Ciocalteu assay and DPPH radical scavenging assay were employed to determine the total phenolic content (TPC) and antioxidant activity of Momordica charantia respectively. Total phenolic content of Momordica charantia extracts ranged from 6.81 mg GAE/g to 23.76 mg GAE/g, whereas the antioxidant activity ranged from 45.07% to 94.66%. The highest phenolic content and antioxidant activity were found in methanolic extract of Momordica charantia pith, chinese cultivar. It contains the lowest inhibitory concentration (1050) value of 0.464mg/ml. There was a significant positive linear correlation between the total phenolic content and antioxidant activity on Momordica charantia extracts. However. the linear regression in extracts using different extraction solvent varies irregularly. Based on the data, pith extracts showed a significantly higher phenolic content and antioxidant activity than the flesh extracts. More attention should be focused on the Momordica charantia pith extracts on the chemo-preventive properties it offered due to its relatively high phenolic content.