Volatile compounds and antioxidant activity of graviola (Annona muricata L.)

In this study, volatile compounds, total phenolic, total flavonoid content and antioxidant activity were carried out in the pulp, peel, and seeds and leaves of Graviola (Annona muricata L.) fruit, which is one of the tropical exotic fruits. For this purpose, DPPH• and ABTS•+ free radical scavenging activity, FRAP and CUPRAC capacity and β-carotene bleaching methods were tested in the extracts obtained from n-hexane, ethyl acetate, methanol and dichloromethane were used solvents. The volatile compound was determined using the GC-MS method in the n-hexane extracts. The highest extraction efficiency (64.14%) was obtained from pulp by using methanol as solvent. The highest TPC and TP content was found in the Y-MeOH extract (244.61 g CAT mg extract-1; 81.32 µg CAT mg extract-1). According to GC-MS results of hexane extracts, terpenoids (53.52%), esters (12.01%) and steroids (9.85%) are the main components of graviola leaves. In the graviola shells, esters (52.2%), aliphatic hydrocarbons (17.84%) and phenolic compounds (12.90%) were found as the major constituents. Esters (47.32%), hydrocarbons (19.84%) and phenolic compounds (15.46%) were the main components in the pulp, while the main components in the seed were fatty acids (67.22%) and terpenoids (9.92%). According to the results of antioxidant activity, the highest DPPH, FRAP and CUPRAC activity was found in the seed of the fruit, while there was no statistically significant difference in ABTS • + radical removal activity for seed and leaves. The β-carotene bleaching activity was highest in the peel and then in the leaves. Pulp showed the lowest activity. All antioxidant characters were evaluated statistically, differences and relationships were found to be significant (p <0.05). There is an important relationship between total phenolic content and total flavonoid content of r = 0.761 **. The highest correlation was found between total flavonoid content and FRAP activity (r = 0.900**). GC-MS analysis of graviola extracts exhibited the presence of various pharmaceutically important chemical compounds with different chemical structure in the extract, and the remarkable total phenolic, flavonoid content and high antioxidant activity activity of the seeds and leaves in this study. Keywords: Graviola (Annona Muricata L.), volatile compounds, GC-MS, Total Flavonoid, FRAP, CUPRAC 2018, 107 Pages