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Cosmetics made from natural ingredients are increasingly popular because they contain bioactive compounds which can provide many health benefits, more environmentally friendly and sustainable. The health benefits obtained from natural-based ingredients include anti-aging, photoprotective, antioxidant, and anti-inflammatory. This article reviewed the potential of selected flavonoids from bajakah tampala (Spatholobus littoralis Hassk.) as the native plant in Indonesia. We present in silico, in vitro, in vivo, and clinical research data on the use of selected flavonoids that have been reported in other extracts.
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PURPOSE: The purpose of this study was to develop antimicrobial bioplastics based on Poly Lactic Acid (PLA) with the addition of chitosan-ZnO, and chitosan-TiO2 to improve antimicrobial properties. METHODS: For the preparation of the bioplastics, PLA with chitosan-ZnO or chitosan-TiO2 were used. The antimicrobial activity, mechanical and thermal properties, and water vapor permeability of bioplastics were evaluated. RESULTS: PLA-chitosan-ZnO indicated a robust antimicrobial activity against bacteria such as Salmonella typhi, Bacillus subtilis, Escherichia coli, Staphylococcus aureus, yeast such as Candida albicans, and fungus Aspergillus niger. No formation of new functional groups in PLA-chitosan-ZnO composites. In comparison to other PLA-based bioplastics, this bioplastic has medium tensile strength, tensile modulus, and elongation percentages with low barrier ability to water vapor. Chitosan-ZnO itself has a greater tensile strength compared to chitosan-TiO2. These two compounds undergo 2 stages of decomposition in a temperature range of 43 °C to 265 °C. The addition of PLA into chitosan-ZnO or chitosan TiO2 causes the bioplastics decomposed in a single stage. It also increases the decomposition temperature of bioplastic. However, compared to chitosan-ZnO or TiO2, the PLA-chitosan-ZnO or TiO2 bioplastics tend to produce a fragile composite indicating by decrease in their tensile strength. CONCLUSION: In general, the addition of chitosan-ZnO into in PLA-based bioplastic produces better antimicrobial properties compared to TiO2.
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We study the structural, electronic, and magnetic properties of the antiferromagnetic-layered oxyarsenide (LaO)MnAs system from the first-principle calculation. The increasing Hubbard energy (U) in the Mn 3d orbital induces the increasing local-symmetry distortions (LSDs) in MnAs4 and OLa4 tetrahedra. The LSD in MnAs4 tetrahedra is possibly promoted by the second-order Jahn-Teller effect in the Mn 3d orbital. Furthermore, the increasing U also escalates the bandgap (E g) and the magnetic moment of Mn (µMn). The value of U = 1 eV is the most appropriate by considering the structural properties. This value leads to E g and µMn of 0.834 eV and 4.31 µB, respectively. The calculated µMn is lower than the theoretical value for the high-spin state of Mn 3d (5 µB) due to the hybridization between Mn 3d and As 4p states. However, d xy states are localized and show the weakest hybridization with valence As 4p states. The Mott-insulating behavior in the system is characterized by the E g transition between the valence and conduction d zx /d zy states. This work shows new physical insights for advanced functional device applications, such as spintronics.
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Recently, the interest in active packaging utilization has increased with population growth, food demand and new consumer trend like food delivery services. This new system, however, requires the use of additives to extend the food product quality and safety as well as in maintaining the shelf-life. This study was to prepare the antimicrobial paper from I. cylindrica coated anionic nanocellulose crosslinked cationic to create a system with the ability to actively control microbe growth in the packaging materials. The process involved pulping of I. cylindrica using semi-chemical and soda chemical method. The antimicrobial paper was prepared by printing the pulp suspension in 60 g/m2 grammage in mold followed by the spray of anionic nanocellulose and subsequent soaking of the paper in cationic solution. The results showed the I. cylindrica paper coated anionic nanocellulose crosslinked with H+ and Al3+ cations were successfully produced. The paper produced was also observed to have antimicrobial activity against Gram-negative of E. coli and S. typhi as well as Gram-positive of S. aureus and B. subtilis bacteria. Furthermore, the best coating method was found on antimicrobial paper coated anionic nanocellulose crosslinked Al3+ as evidenced by smoother and compact surface structure.
