Antioxidant Capacity, Bioactive Compounds and Yield of Extracted Oleoresins from Different Leaf Positions of Pimenta dioica (L.) Merill.

Abstract

Pimenta dioica (L.) Merill. is also known as allspice due to the presence of both flavour and aromatic characteristics of clove, cinnamon, cardamom, and nutmeg. Oleoresins are concentrated plant extracts which contains both essential oil and resins and it is obtained from the evaporation of extraction solvents. There is an emerging demand for oleoresins in the international food sector. The commercial cultivators of allspice in North American countries tend to use berries instead of leaves. There is a huge potential to produce oleoresins from allspice leaves which will be the main scope of this study and to identify the yield, antioxidant capacity and bioactive compounds extracted from the first eight (08) leaf positions of allspice shoots. The oleoresins from above-mentioned leaves were extracted using solvent extraction method. Total antioxidant capacity, total phenolic content, and total flavonoid content in extracted oleoresin were determined using ferric reducing antioxidant power assay, modified Folin-Ciocalteu method and a colorimetric method, respectively. The highest oleoresin yield (8.92 ± 0.03%) was obtained from the 7th leaf position whereas the lowest oleoresin yield (3.68 ± 0.04%) was obtained from the 1st leaf position. There was no significant (p > 0.05) difference in the yield of oleoresin in 6th, 7th and 8th leaf positions. The highest amount of total antioxidant capacity (1555.69 ± 7.04 mg TE/g of oleoresin) and total phenolic content (143.19 ± 2.24 mg GAE/g of oleoresin) were observed in oleoresin extracted from 2nd leaf position whereas highest total flavonoids (718.78 ± 25.24 mg RE/g of oleoresin) were recorded in the 5th leaf position. This study revealed that there were marked bioactive compounds and total antioxidant capacity in oleoresins extracted from leaves of allspice up to 8 leaf position. Oleoresin yield had been increased with leaf maturity.