Determination of Different Chemical Constituents of Fruit, Leaves and Oil of Olea cuspidata (Wild Olive) Grown at Rawalakot, Azad Jammu and Kashmir
Rabab Rafaqat1, Habib Ahmed Rathore1, Tariq Masud2, Imran Hayat1* and Imtiaz Hussain1
The aim of the current project was to investigate the chemical characteristics of fruit, leaves and oil of Olea cuspidata (wild olive). For this purpose, the moisture content, crude fibre, crude protein, total oil, ash content and nitrogen free extract of fruit and leaves were studied. Extracts of wild olive fruit and leaves were made in four different solvents (ethanol, methanol, acetone and water). Total phenolic content (TPC) and total flavonoid content (TFC) of fruit and leaves extracts in these solvents were determined. Oil was extracted from wild olive fruit by the process of solvent extraction and was studied for physicochemical properties like refractive index, specific gravity, pH, free fatty acid, peroxide value, iodine value, saponification number and unsaponifiable matter. Results indicated that fruit and leaves of wild olive grown at Rawalakot Azad Jammu and Kashmir had moisture content (48.33±1.6 and 53.33±1.4 %), crude fiber (4.40±0.3 and 10.0±0.9 %), crude protein (0.80±0.02 and 8.20±0.80 %), total oil (34.43±1.1 and 1.00±0.6 %), ash content (1.71±0.2 and 5.33±0.8%) and nitrogen free extract (10.47±1.9 and 22.14±2.2%), respectively. The higher level of TPC and TFC both in fruit and leaves was observed in methanol (80.10±1.5 mgGAE/g and 112.35±1.9 mgGAE/g) and (21.30±0.9 mg/g and 39.00±1.0 mg/g) followed by ethanol (74.20±1.2 mgGAE/g and 103.32±1.8 mgGAE/g) and (17.10±0.4 mg/g and 33.20±0.9 mg/g), acetone (69.11±1.0 mgGAE/g and 95.20±1.5 mgGAE/g) and (14.30±0.5 mg/g and 28.10±1.2 mg/g) and water (65.00±0.8 mgGAE/g and 84.29±1.4 mgGAE/g) and (11.40±0.7 mg/g and 23.30±0.7 mg/g), respectively. Wild olive oil showed refractive index (1.3±0.1), specific gravity (0.93±0.02), pH value (5.4±0.2), free fatty acid (0.7±0.03), iodine value (79.99±0.58), peroxide value (8.50±0.4 mg/kg), saponification number (180.00±0.91mgKOH/g) and unsaponifiable matter (1.40±0.5). During study it was observed that leaves of wild olive were rich in above mentioned parameters except oil content which was higher (34.43±1.1 %) in fruit. Our study also showed that the leaves of Olea cuspidata are rich source of polyphenolic contents than that of fruit and can be used as additives in different food products in order to get their benefits.