Phytochemical Screening, Extraction, and Determination of the Bioactivities of the Extract-Enriched Polyphenols and Saponins from Musa balbisiana Fruit

Abstract

Many parts of Musa balbisiana have been used widely in traditional medicine, food, or cosmetic purposes. The present study is aimed at obtaining the extract-enriching bioactive compounds from M. balbisiana and determining the bioactive activities of the extract. Total polyphenols and saponins in the extracts were quantified. The response surface method (RSM) was used to optimize the extraction with methanol support. The optimal extraction conditions were at 120 min in 65°C at the material/solvent ratio of 1/36 ( $w/v$ ). The obtained extract containing 51.72 mg/gGAE of total polyphenols (TPC) and 41.66 mg/g of saponins (TSC) was evaluated for antioxidant, antibacterial, antifungal, and antidiabetic abilities. The extract of M. balbinasia fruit exhibited strong antioxidant activity. The IC50 112.57 μg/mL (DPPH) and 14.49 μg/mL (ABTS). The absorbance of the extract was $1.653\pm 0.030$ at 250 ppm (RP assay). The antibacterial and antifungal inhibition exhibited a correlation with TPC and TSC. The extract inhibited Gram (+) S. aureus better than Gram (-) E. coli, while the inhibition percentage (I%) against A. flavus reached over 70% at 800 ppm. The IC50 value of the extract for anti-inflammatory activity was 187.91 μg/mL. The antidiabetic assessment revealed that methanolic extract showed quite strong inhibition with α-amylase (IC50 68.26 μg/mL) and α-glucosidase (IC50 72.61 μg/mL). The results of the study showed that M. balbinasia fruit is a potential source of bioactive phytochemicals, which can be used as a plant-based antioxidant, antibacterial, antifungal, anti-flammatorial, and antidiabetic agent. This is valuable information to support further studies to exploit and apply it in functional food, pharmaceutical, and cosmetic industries.