Evaluation of Antioxidant, Antimicrobial Activity and Phytochemical Content of Garcinia prainiana-An Endangered Plant Khairuddin Nur Nasrah Mohd1, Asang Gogula Selvi1, Ahmad Aryati2, Taib Wan Rohani Wan2, Alias Nadiawati1,* 1School of Agriculture Sciences and Biotechnology, Faculty of Bioresources and Food Industry, Universiti Sultan Zainal Abidin, Besut Campus, 22200, Besut, Terengganu, Malaysia 2Faculty of Health Sciences, Universiti Sultan Zainal Abidin, Gong Badak Campus, 21300, Kuala Terengganu, Terengganu, Malaysia *Corresponding Author E-mail: nadiawati@unisza.edu.my
Online published on 20 December, 2018. Abstract Garcinia praniana comes from the family Gruttiferae and has been listed as one of the endangered species under IUCN Red Listed of Threatened Species. The present study was Aimed to evaluate the potential antioxidant, antimicrobial and phytochemicals content (TPC and TFC) of leaves, twig and fruit of Garcinia prainiana by ethyl acetate extract. Antioxidant activity was tested using free radical diphenylpicrylhydrazyl (DPPH) assay and showed the highest inhibition at 0.4 mg/ml for both leaves extract (77.41%) and fruit extract (36.02%) respectively. Meanwhile, for twig, the highest percentage of inhibition was at 0.5 mg/ml for 39.78%. Among all samples tested, IC50 was only recorded for leaves extract of Garcinia prainiana at 0.19 mg/ml compared to Trolox at 0.023 mg/ml. Potential antimicrobial activity of the extracts were carried out using disc diffusion method against 3 type of gram-positive and 4 type of gram-negative bacteria. Results have indicated that 100 mg/ml of leaves extract showed antimicrobial activity against Escherichia coli ATCC 35218, Staphylococcus aureus ATCC 33591, Bacillus cereus ATCC 14579, and Acinetobacter baumannii ATCC 19606. In contrast, twig and fruit showed weak antimicrobial activity against a few bacteria strains. Quantitative phytochemicals content were also carried out to measure compounds presence in Garcinia prainiana ethyl acetate extract. Total phenolic contents of the extracts were measured by Folin-Ciocalteau method. The highest phenolic compound presence was recorded from leaves extract (86.047 ± 3.039 mg/g) followed by fruit extract (21.811 ± 5.022 mg/g) and twig extract (2.512 ± 3.446 mg/g). In addition, the highest flavonoid content was recorded in fruit extract (73.188± 1.056 mg/g) followed by twig extract (49.932 ± 3.057 mg/g) and leaves extract (26.676 ± 2.062 mg/g). From this study, total phenolic content showed a good correlation with antioxidant activity, but not with total flavonoid content. Top Keywords Garcinia prainiana, DPPH assay, antioxidant, antimicrobial, phytochemical, ethyl acetate. Top |