EFFECT OF SOAKING, GERMINATION AND ROASTING ON THE PHYTOCHEMICAL AND ANTI-NUTRITIONAL COMPONENTS OF PUMPKIN SEEDS (Cucurbita moschata)

Abstract

Pumpkin seed (Cucurbita moschata) collected from Morang district, Nepal was studied to explore the effect of roasting at 200oC for 5 min and 10 min, soaking for 12hrs followed by cabinet drying followed by roasting at 200oC for 10 min and 48h, 96h, 144h, and 192h of germination followed by cabinet drying followed by roasting at 200oC for 10 min on its bioactive compounds (phenolic acid, flavonoid and anti-oxidant activity) and anti-nutritional components (tannin, phytic acid and oxalate). The crude extracts of samples were prepared using 80% methanol by maceration technique for analysis of total phenolic content, total flavonoid content and anti- oxidant activity. Experimental data was analyzed using software Genstat 12th Edition. The mean value of tannin, phytic acid, oxalate, phenolic content, flavonoid and DPPH activity of pumpkin seeds were 204.61 mg/100g, 22.45 mg/100g, 383.7 mg/100g and 310.4 mg/100g and 10.6 (%) respectively. All the treatments showed (p<0.005) significant reduction of antinutrients and increased the bioactive compounds of pumpkin seeds where both single and combination treatments were found increasing the bioactive compounds, and decreasing antinutrient components. The combination treatments i.e., germination and roasting reduced the oxalate, phytic acid content and increase flavonoid, DPPH activity more effectively than other treatment methods. However, only roasting was most effective in reducing tannin and increasing total phenolic content, so the resulting reduction in anti nutrients and increment of bioactive compound were obtained through both single and combined treatments.