Study of antioxidants contains in Leucaena Leucocephala (Petai Belalang) and potential application as natural based UV protection in High Density Polyethylene (HDPE)

Leucaena Leucocephala (Lam.) de Wit (Petai Belalang) is a medium plant which belong to the group of tropical breed, traditionally used as food for both human and animal, and being applied in medical and cosmetic. The main objective of this work was to investigate the different solvent for extracting bioactive compound composition in seeds and leaves of L. leucocephala (Petai Belalang), to identify and characterize the type of bioactive compound composition in both seed and leaves of L. leucocephala (Petai Belalang) and last but not least to evaluate the potential of antioxidant activity of L. leucocephala (Petai Belalang) extract in high density polyethylene (HDPE). For antioxidant activity of leaves by using free radical diphenylpicrylhydrazyl (DPPH) method, higher concentration was recorded by extraction using methanol (dried sample) which is 8247.0 mg/L, for total phenolic content higher concentration was recorded by extraction using deionized water (dried sample) which is 4276.0 mg/L, for total flavonoid content by using colorimetric assay higher concentration was recorded by extraction using methanol (dried sample) which is 4439.0 mg/L, and for phosphorus analysis higher concentration was recorded by extraction using methanol (dried sample) which is 71.057 mg/L. While, Antioxidant activities for seeds are higher under extraction using methanol (dried sample) which is 593.09 mg/L, total phenolic content are higher under extraction using deionized water (dried sample) which is 5587.50 mg/L, total flavonoid content are higher under extraction using methanol (dried sample) which is 445.05 mg/L, and phosphorus analysis are higher under extraction using methanol (dried sample) which is 73.817 mg/L. The Fourier-transform infrared spectroscopy (FTIR) and High Performance Liquid Chromatography (HPLC) analysis was done in order to detect and identified the bioactive compound in sample. As O-H bond is the main element of antioxidant and phenolic compound, the FTIR analysis shows for the high possibilities for the present of antioxidant and phenolic compound in L. leucocephala. HPLC analysis for both seeds and leaves revealed the presence of caffeic acid, apigenin, quercetin, formic acid, isorhamnetin, and luteolin which is all the compounds are belong to the group of antioxidant. The strongest extraction solvent which extracted higher concentration of antioxidant was chosen for further application as bio additives in high density polyethylene (HDPE). The final product will undergo tensile test, higher resolution optical microscopic, colour fastness and degradation analysis and antimicrobial assay to measure the effect of added bio additives. Sample with bio additives resulted for improvement in its strength after 1000 hours UV exposure as the percent of degradation shows for smooth pattern compared to sample without bio additives. The antioxidants also react as positive antimicrobial when undergoes antimicrobial assay. Overall, the presented results show that bio active compounds extracted from Leucaena Leucocephala has a high potential to be used as natural based UV protection in plastic.