Noble metal nanoparticles (NMNPs) are viable alternative green sources compared to the chemical available methods in several approach like Food, medical, biotechnology, and textile industries. The biological synthesis of platinum nanoparticles (PtNPs), as a strong photocatalytic agent, has proved as more effective and safer method. In this study, PtNPs were synthesized at four different temperatures (25 °C, 50 °C, 70 °C, and 100 °C). PtNPs synthesized at 100 °C were smaller and exhibited spherical morphology with a high degree of dispersion. A series of physicochemical characterizations were applied to investigate the synthesis, particle size, crystalline nature, and surface morphology of PtNPs. The biosynthesized PtNPs were tested for the photodegradation of methylene blue (MB) under visible light irradiations. The results showed that PtNPs exhibited remarkable photocatalytic activity by degrading 98% of MB only in 40 min. The acid phosphatase mediated PtNPs showed strong bacterial inhibition efficiency against S. aureus and E. coli. Furthermore, it showed high antioxidant activity (88%) against 1,1-diphenyl-2-picryl-hydrazil (DPPH). In conclusion, this study provided an overview of the applications of PtNPs in food chemistry, biotechnology, and textile industries for the deterioration of the natural and synthetic dyes and its potential application in the suppression of pathogenic microbes of the biological systems. Thus, it could be used as a novel approach in the food microbiology, biomedical and environmental applications.

Superabundant date fruit production in Al-Qassim in the Kingdom of Saudi Arabia (KSA), a plentiful region for producing date syrup resulting in massive amounts of date fiber (DF), causes environmental issues with what is considered dietary waste. However, no food producer or researcher has thought of the valorization of DF by extracting the crude polysaccharides that can be converted to nanoparticles (flours) to increase its functional group and enhance its functionality. Using the DF was the primary goal, with the new biscuits used within the current study investigated as a potent integrated approach for controlling obesity levels and its effects. Obesity is one of the most important human problems worldwide, connected to many metabolic diseases, e.g., diabetes mellitus and cardiovascular disease. Its prevalence has recently increased among Saudi children and adolescents. An investigation of the biological effects of the formulated products was carried out by feeding the formulated biscuits with different DF levels (5, 10 and 15%) to obese albino rats, in addition to positive and negative control groups, to evaluate the effect of a reduced calorie product on controlling their body weight and health stats (lipid profile, blood sugars, kidney and liver functions). The collected data showed that the most positive results were obtained from rats fed diets supplemented with 10% DF biscuits. All TCHO, TrGs, HDL, and HDL were decreased to the best levels in this group compared to the positive control group (148.23, 145.30, 37.50, and 81.67 vs. 238.37, 199.07, 62.57, and 135.99, respectively). To conclude, DF supplementation presented anti-obesity properties in animal models; however, more epidemiological trials are needed.

Background: Synthetic antioxidants have toxigenic effects, there is therefore growing interest in substituting them with natural antioxidants. Attention is being focused on extracting them from agricultural industry residuals to minimize costs. Legume seed hulls could be cheap sources of such natural antioxidants. Objective: This study aims to unravel potential free radical scavenging activity, antioxidant activity, and total phenolic and flavonoid contents of some legumes’ hulls extracted by different solvents and evaluate their efficacy to enhance sunflower oil stability. Method: Legume hulls extracted by different solvents were evaluated for their antioxidant activity coefficient (AAC), free radical scavenging activity [by 2,2-diphenyl-1- picrylhydrazyl (DPPH)], and phenolic and flavonoids contents. The protection factor and induction periods (rancimat test) of the highest activity extracts were evaluated. Results: Sunflower seed hull ethyl acetate extract, lupine seed hull ethanol extract, and mung bean hull petroleum ether extract exhibited stronger DPPH scavenging activity, AAC, and protection factor values than other solvents. Ethyl acetate extracts of sunflower seed hulls showed an antioxidant and scavenging activity close (P>0.05) to that detected for α-tocopherol. Conclusions: Legume hulls may possess strong free radical scavenging and antioxidant activity. The analogous effect between sunflower hull extract and α-tocopherol make it a potential, cheaper substitute of α-tocopherol in food systems. Highlights: The analogous effect between sunflower hull extract and α-tocopherol give it the potency to allow substitution at a concentration of 0.5% of sunflower hull ethyl acetate or 1% of lupine hull ethanol extract instead of 0.5% α-tocopherol to enhance induction periods and protection factors of sunflower oil.