Sterculia populifolia is commonly used as the ingredient of traditional herb in Timor Island, East Nusa Tenggara, Indonesia. It contains flavonoid which roles as antioxidant. This flavonoid can be sunblock due to the existence of chromophore which commonly gives color to plants. This study aimed to determine the activity of antioxidants and sunblock through the value of Sun Protection Factor (SPF) from Sterculia populifolia extract-based cream and cream preparation extract. This cream was formulated into four formulas; extract concentrate 0% (F0), 1% (F1), 3% (F2) and 5% (F3). The result showed that the whole formula of cream preparation filled the physical stability parameter. F3 cream had IC50 79.179 ppm value while SPF had 5.6 value higher than F1 and F2. The smaller the IC50 value, the bigger antioxidant activity and SPF increased.

The public widely uses kersen (Muntingia calabura L) fruit for consumption and treatment because Kersen fruit has various vitamins, minerals, and secondary metabolite compounds that reduce free radicals. The purpose of this study was to see the effectiveness of kersen fruit as an antioxidant agent. In this study, the samples used were ethanol extract (EE), Aqueous ethanol fraction (EF), ethyl acetate fraction (EAF), and n-hexane (HF) fraction from kersen fruit (Muntingia calabura L). The samples were evaluated by observing the antioxidant activity profile using various methods, i.e., nitric oxide, β-carotene bleaching assay, hydroxyl radicals, and iron chelating. The results of this study showed that the IC50 values of EE (31.05 μg/mL), AEF (33.86 μg/mL), FEA (40.48 μg/ml) gave powerful antioxidant activity while HF showed weak results (459 μg/ml). In the nitric oxide method. The hydroxyl radical method with IC50 values of 32.06 μg/mL (EE), 38.73 μg/mL (EF), 22.18 μg/mL (EAF) gave very strong activity, and 53.37 μg/mL (HF) with strong activity. The β-carotene bleaching method gave powerful antioxidant activity results with IC50 values <50 μg/mL in each sample. The Iron Chelation method showed weak antioxidant activity (IC50 > 200 μg/mL) of each sample. Based on the results obtained, it can be concluded that the antioxidant activity of extracts and fractions in kersen fruit has a different activity profile according to the test method used.

All the mice were caged in groups of six under environmentally controlled room with 12 h light/dark cycle and provide standard rodent diet and water ad libitum until further 30 weeks of age. The 30 weeks old mice were then randomly allocated into the four experiment groups that matched for body weight (Table 3). Diets Standard diet (control diet) D12102 and high fat diet Clinton/Cybulsky D12109 used, were purchased from Research Diet Inc. USA. The control diet D12102 contained 10% calory from fat. The high fat diet contained 40% calory from fat mainly from cocoa butter with 1.25% cholesterol (w/w)

The research of manufacturing chitosan from shrimp shell waste , and their use as a stabilizer in the manufacture of silver nanoparticles has been done. The aim of the research was to synthesize silver nanoparticles using chitosan as a stabilizer by chemical reduction method and determine the effect of chitosan concentration on the stability of Ag nanoparticles. In this study, the raw material used is shrimp shell powder and then processed in several stages, eliminating proteins, demineralization, and deacetylation. Chitosan obtained is 16.4 % of shrimp shell powder, with a degree of deacetylation of 85 %. Chitosan is used to synthesize silver nanoparticles as a reducing agent of silver ions in silver nitrate solution and is expected to be stabilizer. Sample containing 45 mg of chitosan and 1000 ppm AgNO3 has 421,60 nm of maximum wavelength, and the average particle size is 154.07 nm.

Paku Atai Merah tubers with the Latin name Angiopteris ferox Coupel have been used by the Dayak people as empirical treatment and have anticancer and antioxidant activity. The purpose of this study was to find out more the movement of extracts and fractions of Paku Atai Merah tubers in reducing free radicals using the total antioxidant capacity (TAC), CUPRAC, and Iron chelating methods. In this study, the sample used was the ethanol extract (EE) of A.ferox Copel and then partitioned using n-hexane (FHP), ethyl acetate (FEAP), and aqueous-ethanol (FEP) solvents. The effectiveness of the sample in reducing free radicals with various antioxidant assay methods. The results obtained from this study indicate that the extract and fraction of Paku Atai Merah tubers have good effectiveness as an antioxidant agent. The total antioxidant capacity (TAC) method showed that EAP had a total antioxidant capacity of 101.60 μM/mg QEAC compared to EE (44.62 μM/mg QEAC), FEAP (89.88 μM/mg QEAC), and FHP (81.21 μM/mg QEAC). In the CUPRAC method using gallic acid as a standard for comparison, the results obtained were EE (4.00 μM/mg GEAC), FHP (1.45 μM/mg GEAC), FEAP (8.66 μM/mg GEAC), and APA (8.72 μM/mg GEAC). The antioxidant activity using the chelating iron method in each sample of EE, HPA, EAP, and APA showed activity with IC50 values of 384 μg/mL, 387.41 μg/mL, 339.23 μg/mL, and 347.3 μg/mL. Based on the results obtained from this study, it can conclude that the extract and fraction of Paku Atai Merah tubers have an excellent antioxidant agent to develop as a food supplement.