Chemical composition, Antioxidant capacities and storage stability of Citrus macroptera and Garcinia pedunculata fruits

An attempt was made to gain an insight about chemical compositions and antioxidant capacities of selected underutilized fruits Satkara (Citrus macroptera) and Taikor (Garcinia pedunculata) in Sylhet, Bangladesh. The analysis showed β Carotene and Vitamin C in Satkara 22±1.50 mg/100g and 210.43±0.40 mg/100g whereas Taikor contains 45±1.00 and 142.83±2.03 mg/100g respectively. The mineral composition of both fruits is appreciable. Total polyphenol content (TPC) and total flavonoids (TF) in Satkara and Taikor were 22.76±0.52 mg GAE/100g and 18.98±0.65 mg GAE/100g, 23.38±1.0 mg RE/g and 18.33±1.12 mg RE/g respectively. The antioxidant capacities of these fruits were evaluated by DPPH and ABTS method, values expressed as TEAC (Trolox Equivalent Antioxidant Capacity). In case of ABTS showed that the value 19.06±0.18 TEAC (μM/g) and 2318.44±5.60 TEAC (μM/g); for DPPH showed 16.20±0.04 TEAC (μM/g) and 1813.88±12.62 TEAC (μM/g) in Satkara and Taikor respectively. The total polyphenol content showed the positive correlation with the antioxidant capacities and ascorbic acid contents of these fruits. Storage studies at two different temperatures at 5ºC for 15 days and -18ºC for 3 months long storage period antioxidant activity shown to be stable but vitamin C content decreases significantly. The results demonstrate that Citrus macroptera and Garcinia pedunculata fruits contained the considerable levels of nutrients and antioxidant capacity.