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Objective: To develop a thin-layer chromatography (TLC) densitometric method for the determination of oxyresveratrol content in Artocarpuslakoocha heartwood and in the traditional drug ‘Puag-Haad’. Materials and Methods: Sample solution of A. lakoocha heartwood was prepared by Soxhlet extraction of the plant material in ethanol, whereas the Puag-Haad solution was obtained by dissolving the drug in methanol. Analysis of each sample solution was performed on a Silica gel 60 F₂₅₄ TLC plate (20 × 10 cm) with methylene chloride/methanol (85:15) as the mobile phase. After development, the TLC plate was examined with a TLC scanner in the absorbance mode at 254 nm. The newly developed analytical method was validated using an authentic sample of oxyresveratrol previously isolated from A. lakoocha heartwood, and was used to analyze the oxyresveratrol content in samples of A. lakoocha heartwood and the traditional drug Puag-Haad. Results: A sensitive and reliable TLC densitometric method was successfully developed. The method was validated in terms of accuracy (99.11–102.60%) and precision (1.66–4.23% coefficient of variation). The limits of detection and quantitation were 15.6 and 52 ng/spot, respectively. The amounts of oxyresveratrol in 3 samples of A. lakoocha heartwood collected from its natural habitat were 49.0–182.3 mg/g, whereas those in 11 commercial samples were in the range of 23.4–69.6 mg/g. The oxyresveratrol contents in 2 samples of traditional drug Puag-Haad were 780.1 and 837.5 mg/g. Conclusion: The TLC densitometric method developed in this study is a simple, convenient, sensitive and reliable procedure. It was an effective analytical tool for the evaluation of oxyresveratrol content in both A. lakoocha heartwood and the traditional drug Puag-Haad.

The COVID-19 pandemic has intensively disrupted global health, economics, and well-being. Andrographis paniculata (Burm. f.) Nees has been used as a complementary treatment for COVID-19 in several Asian countries. This review aimed to summarize the information available regarding A. paniculata and its constituents, to provide critical points relating to its pharmacological properties, safety, and efficacy, revealing its potential to serve as a source of lead compounds for COVID-19 drug discovery. A. paniculata and its active compounds possess favorable antiviral, anti-inflammatory, immunomodulatory, and antipyretic activities that could be beneficial for COVID-19 treatment. Interestingly, recent in silico and in vitro studies have revealed that the active ingredients in A. paniculata showed promising activities against 3CLpro and its virus-specific target protein, human hACE2 protein; they also inhibit infectious virion production. Moreover, existing publications regarding randomized controlled trials demonstrated that the use of A. paniculata alone or in combination was superior to the placebo in reducing the severity of upper respiratory tract infection (URTI) manifestations, especially as part of early treatment, without serious side effects. Taken together, its chemical and biological properties, especially its antiviral activities against SARS-CoV-2, clinical trials on URTI, and the safety of A. paniculata, as discussed in this review, support the argument that A. paniculata is a promising natural source for drug discovery regarding COVID-19 post-infectious treatment, rather than prophylaxis.

Thermosensitive chitosan/β-glycerophosphate (CS/BGP) systems have been developed as injectable hydrogels. However, the hydrogels exhibited poor mechanical properties due to their physically crosslinked networks. In this work, CS/BGP hydrogels were reinforced by covalent crosslinking using genipin (GE) and concomitantly semi-interpenetrating networks using pullulan (PL). Based on response surface methodology, the optimized formulation was composed of CS (1.05%, w/v), PL (1%, w/v), BGP (6%, w/v), and GE (70.79 mcg/mL). The optimized hydrogels exhibited Young’s modulus of 92.65 ± 4.13 kPa and a percentage of equilibrium swelling ratio of 3259.09% ± 58.90%. Scanning electron micrographs revealed a highly porous structure with nanofibrous networks in the CS/PL/BGP/GE hydrogels. The chemical interactions between the compositions were investigated by Fourier-transform infrared spectroscopy. Rheological measurements illustrated that the optimized hydrogels displayed sol–gel transition within one minute at 37 °C, a lower critical solution temperature of about 31 °C, and viscoelastic behavior with high storage modulus. Furthermore, the optimized hydrogels demonstrated higher resistance to in vitro enzymatic degradation, compared to the hydrogels without GE. Our findings could suggest that the thermosensitive CS/PL/BGP/GE hydrogels with enhanced mechanical properties and swelling capacity demonstrate the potential for use as scaffolds and carriers for cartilage tissue engineering and drug delivery applications.

Background: Cissus quadrangularis Linn. (CQ) has been used in Indian and Thai traditional medicine for healing bone fractures because of numerous active ingredients in CQ. It is still unclear which compounds are the active ingredients for bone formation. Methods: The molecular docking technique, the ethanolic extraction along with hexane fractionation, and an in vitro experiment with a human osteoblast cell line (MG-63) were used to narrow down the active compounds, to prepare the CQ extract, and to test biological activities, respectively. Results: The molecular docking technique revealed that quercetin and β-sitosterol had highest and lowest potential to bind to estrogen receptors, respectively. Compared to the crude ethanol extract (P1), the ethanolic fraction (P2) was enriched with rutin and quercetin at 65.36 ± 0.75 and 1.06 ± 0.12 mg/g, respectively. Alkaline phosphatase (ALP) activity was significantly enhanced in osteoblasts exposed to the P2 in both tested concentrations. The amount of hydroxyproline was slightly increased in the P1 treatment, while osteocalcin was inhibited. Moreover, the P2 significantly activated osteoprotegerin (OPG) and inhibited receptor activator of nuclear factor κ ligand (RANKL) expression. Conclusions: Taken together, the enriched rutin and quercetin fraction of CQ triggered the molecules involved in bone formation and the molecules inhibiting bone resorption.