Search

Four flavonoid glycosides, namely quercetin-3-O-rhamnoside (1), kaempferol-3-O-β-D-glucopyranosyl (2), kaempferol-7-O-α-L-rhamnopyranoside (3), and kaempferol-3-O-β-D-glucopyranosyl-7-O-α-L-rhamnopyranoside (4), from Nephelium lappaceum L. seeds were evaluated for their efficacy against melanin inhibition in B16F10 melanoma cells and tyrosinase inhibition. Among them, kaempferol-7-O-α-L-rhamnopyranoside (3) displayed the highest potency in both activities without any significant cytotoxicity. The combination of compound 3 and arbutin in specific proportions demonstrated a synergistic effect (CI < 1) in inhibiting melanin production in B16F10 cells and tyrosinase inhibition. Additionally, a cosmetic formulation containing compound 3 and arbutin as active ingredients exhibited favorable stability under accelerated storage conditions. Quantitative analysis indicated that compound 3 and arbutin levels in the formulation were above 90% after one month of storage. Determination of the formulation's shelf life using the Q10 method, estimating it to be around 5.2 months from the date of manufacture. The synergy between arbutin and kaempferol-7-O-α-L-rhamnopyranoside (3) extracted from N. lappaceum substantially enhances both the whitening effectiveness and the stability of cosmetic formulations., (© 2023. The Author(s).)

Andrographis paniculata (Burm. F.) Nees is a medicinal plant previously reported with broad-spectrum antivirals but the mode of inhibition remains elusive. The objective of this study was to identify the most active fraction from A. paniculata ethanol extract (APE, APE-2A, APE-2B and APE-2C) and dry powder extract (APSP) against influenza A (H3N2), representing RNA viruses, and herpes simplex virus-1 (HSV-1), representing DNA viruses. The results showed that the fractions APSP, APE, APE-2B, and APE-2C directly neutralized the HSV-1 and influenza A (H3N2) when incubated at room temperature for 60 min before infecting the cells. The results also showed that the additional APE-2A fraction also directly neutralized the influenza A (H3N2), but not the HSV-1. The APE, APE-2B and APE-2C inhibited the HSV-1 by more than 0.5 log when the fractions were introduced after infection. Similarly, the APSP and APE inhibited the influenza A (H3N2) more than 0.5 log after infection. Only 50 μg/mL APE-2C inhibited the viruses greater than 0.5 log. In addition, A. paniculata extracts were also evaluated for their interfering capacities against nitric oxide (NO) production in LPS-activated RAW 264.7 macrophages. As well, APE-2C potently inhibited NO production at the IC 50 of 6.08 μg/mL. HPLC and LC-MS analysis indicated that the most actively antiviral fractions did not contain any andrographolide derivatives, whereas the andrographolide-rich fractions showed moderate activity., (© 2023. The Author(s).)

Introduction: Cannabidiol (CBD), cannabinol (CBN), and Δ 9 -tetrahydrocannabinol (Δ 9 -THC) are major cannabinoids in cannabis resin and products. The kinetic of the chemical reaction of resin cannabis is important for product development and storage. A few reports are available in the literature on the rate of CBD and Δ 9 -THC degradation, and CBN formation in dried resin and solutions of various pH. Materials and Methods: Thermal degradation of CBD, Δ 9 -THC, and formation of CBN was studied at 50°C, 60°C, 70°C, and 80°C for dried cannabis resin. The effect of pH and temperature on cannabinoids transformation in cannabis solution was also examined at pH 2, 4, 6, 8, 10, and 12 and at 40°C, 50°C, 60°C, and 70°C. High-performance chromatography coupled with diode-array detection (HPLC-DAD) was used for the analysis of CBD, CBN, and Δ 9 -THC transformation. The values of activation energies ( E a ), shelf-life (t 90% - t 110% ), and rate constant ( k ) were calculated for the CBD, Δ 9 -THC, and CBN. The effect of temperature and pH on the dried cannabis resin was adequately modeled with the Arrhenius equation. Results: The results indicated that the chemical kinetics in the thermal degradation of CBD, Δ 9 -THC, and formation of CBN were the zero-order, pseudo-zero-order, and first-order reactions, respectively, in cannabis resin. The first-order and pseudo-first-order degradation kinetics were evidenced for CBD and Δ 9 -THC, respectively, in cannabis solutions, whereas the zero-order formation kinetic was detected for the CBN. The transformation rate of the CBD, CBN, and Δ 9 -THC increased with increasing temperature, especially as temperature increased to 70°C at pH 2.0. The optimum pH for CBD stability was between pH 4 and 6, whereas the optimum pH for Δ 9 -THC stability was between pH 4 and 12. Conclusion: The major cannabinoids (CBD, CBN, and Δ 9 -THC) reacted more quickly at high temperature and in an acidic solution. Especially, the minimum transformation of CBD, CBN, and Δ 9 -THC was achieved by using on a low temperature, slightly to moderately acidic pH values, and short-time processing. These results may help to improve the storage condition of CBD, CBN, and Δ 9 -THC products and in the manufacturing process.