Comparison of the Chemical Compositions, Physiochemical Analysis and Other Bioactive Compounds of Various Pumpkin (curcubita pepo l.) Varieties.

Abstract

The chemical composition of Curcubita pepo Egyptian, Chinese seeds varieties and Egyptian leaves were studied. Total phenolic and total flavonoids compounds and scavenging radical effect on 2, 2-diphenylpicrylhydrazyl (DPPH) were investigated. The specific phenolic and flavonoid composition quantification for ethanolic and water extracts were performed by HPLC. From the obtained results, total lipid represents the major component of Curcubita pepo seeds (38.57-39.65%) followed by carbohydrate (28-31.75%) and protein (18.81-22.31%). The content of Curcubita pepo leaves, lipids and protein (6.30 – 11.81 %) was lower than of Curcubita pepo seeds. The oil obtained from the pumpkin seed's varieties, such as Egyptian and Chinese had refractive index value ranges from 1.467 to 1.469, specific gravity value ranges from 0.911 to 0.912, acid value ranges from 3.8 to 5.2 mg KOH/g oil, iodine ranges from (120.63 to131.87 mg I 2 /100 g), saponification value ranges from 182.99 to 187.31 mg KOH/g and peroxide value ranges from 4.89 to 6.00 (meq O 2 /kg oil). Pumpkin ( Cucurbita pepo ) oil contains a high amount of unsaturated fatty acids. The unsaturated fatty acids of Curcubita pepo oil were (79.03 and 78.79 %) of total fatty acids, respectively. The major unsaturated fatty acids in Egyptian and Chinese pumpkin seeds varieties oil were linoleic (50.22-49.51%) and oleic acid (28.82 -28.33%), while total saturated fatty acids content was (21.21-21.01%). The tocopherols content of Curcubita pepo Chinese seed oil was found to be 5.44 µg/mL of oil for α-tocopherol, 6.72 µg/mL of oil for γ -tocopherol and 10.72 µg/mL of oil for β-tocopherol. The tocopherols content of Curcubita pepo Egyptian seed oil was 7.69 µg/mL of oil for α-tocopherol and 1.22 µg/mL of oil for β-tocopherol. Total phenolic, total flavonoids and antioxidant activity content of ethanolic pumpkin leaves extracts were higher than aqueous extracts. Ethanolic pumpkin extracts were rich in phenolic compounds. The values were found to be highest quantities, cinnamic (8.33 µg/mL), syringic (5.10 µg/mL), pyrogallol (1.46 µg/mL), ellagic (0.97 µg/mL) and gallic (0.87 µg/mL). In additional to presence four flavonoid compounds were kampferol (16.84 µg/mL), apigenin (12.88 µg/mL), quercetin (4.55 µg/mL) and luteolin (1.64 µg/mL).