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Thanaka (Hesperethusa crenulata) stem bark has been utilized as natural cosmetics, particularly in Myanmar since a thousand years ago. However, information on bioactive compounds is still limited. This research aimed to quantify the marmesin levels in the extracts of Thanaka stem bark using High-Performance Liquid Chromatography (HPLC). Thanaka stem bark samples were obtained from diverse markets in Myaing Township, Magway Region (S1), Monywa Township (S2), and Shwebo Township (S3) from Sagaing Region. Moreover, antioxidant activity, cytotoxicity, collagen production, and anti-melanogenic effects were investigated. The marmesin content in Thanaka stem bark extracts derived from S1, S2, and S3 were 12.86 ± 0.48, 1.38 ± 0.09, and 7.61 ± 0.68 mg/g dry extract, respectively. The results of Pearson's correlation coefficient revealed a significant relationship between antioxidant activity and total phenolic content. S1 exhibited the most favorable IC50 values for DPPH and ABTS which were 56.43 ± 1.49 µg/mL, and 14.04 ± 0.05 µg/mL, respectively. Additionally, it demonstrated a corresponding FRAP value of 337.62 ± 11.00 mM in terms of Ferrous sulfate equivalent per gram dry extract. Cell assays revealed no toxicity in immortalized human epidermal keratinocytes (HaCaT cells) treated with extracts at concentrations below 1000 µg/mL. Moreover, human foreskin fibroblasts (HFF-1 cells) exhibited enhancement in collagen production without any observed toxicity. Furthermore, Thanaka stem bark extracts could reduce melanin content and provide moderate tyrosinase inhibition in murine melanoma (B16F10) cells without toxicity. In conclusion, Thanaka stem bark extract demonstrates promising biological activities for development as a multifunctional skin care product. [ABSTRACT FROM AUTHOR]

Background: Marmesin, an important coumarin isolated from Broussonetia kazinoki, has been proposed to possess many pharmacological activities including anti-tumor activity. However, the anti-cancer effect of marmesin on esophageal cancer (EC) has not been characterized. The study aimed to explore the anti-cancer role of marmesin using EC cell lines in vitro. Methods and results: Cell proliferation was evaluated by CCK-8 and Edu cell proliferation assays and apoptosis was detected by TUNEL assay. Western blot analysis was used to determine the expression of Ki67, proliferating cell nuclear antigen (PCNA), Bcl-2, Bax, phosphatidylinositol 3-kinase (PI3K), phosphoryrated-PI3K (p-PI3K), protein kinase B (Akt), and phosphoryrated-Akt (p-Akt). The mechanism of action of marmesin was analyzed using network pharmacology approach. Marmesin exhibited anti-proliferative effect against EC cells, which was further confirmed by the reduced expression of Ki67 and PCNA. Marmesin exerted pro-apoptotic activity on EC cells by downregulating Bcl-2 and upregulating Bax. According to the results from network pharmacology approach, we speculated that PI3K/Akt pathway may participate in the effect of marmesin on EC cells. Additionally, the PI3K/Akt pathway was suppressed by marmesin in EC cells. Moreover, forced expression of Akt reversed the inhibition of cell proliferation and induction of apoptosis induced by marmesin in EC cells. Conclusions: Marmesin exerted anti-cancer activity in EC cells by inhibiting the PI3K/Akt pathway. [ABSTRACT FROM AUTHOR]

In this study, potential bioactive compounds in the products of the solid fermentation of the paper mulberry tree bark (Broussonetia papyrifera) with a white rot fungus (Perenniporia tephropora) were investigated. Fractionation of methanolic extracts from the fermented products of the bark led to the isolation of 10 known compounds, namely broussonin B (1), broussonin A (2), 7,4'-dihydroxy-3'-prenylflavan (3), cathayanon H (4), broussoflavonol B (5), isoliquiritigenin (6), broussochalcone B (7), glyasperin A (8), marmesin (9), and vomifoliol (10). Their structures were determined by spectroscopic analysis (including considerations of MS, 1H, 13C NMR, COSY, HMQC, and HMBC spectra) and compared with structures that had been published in the literature. Of these compounds identified, cathayanon H (4) and glyasperin A (8) were isolated for the first time from the paper mulberry tree. Vomifoliol (10) was produced from the bark only after fermentation with white rot fungi. It was observed that concentrations of marmesin (9) and vomifoliol (10) generally increased with an increase in fermentation time, whereas concentration of compounds 1‒8 in the fermented products decreased during the same period. Biological tests showed that the tyrosinase inhibitory activity of marmesin (9) (IC50 = 168.0 μM) was similar to that of arbutin, a well-known tyrosinase inhibitor, whereas vomifoliol (10) exhibited no tyrosinase inhibition activity at any concentration higher than 2 mM. Accordingly, both solids and the liquid broth left after fermentation of the paper mulberry tree bark with the aforementioned white rot fungus could be developed for potential use in industrial applications. [ABSTRACT FROM AUTHOR]

Objectives The aim of this study was to evaluate the hepatoprotective potential of a methanolic extract and of marmesin isolated from the root bark of Feronia limonia. Methods Activity levels of aspartate aminotransaminase (AST) and alanine aminotransaminase (ALT), cell viability and cell death were evaluated in HepG2 cells (human liver hepatoma cells) treated with CCl4 in the presence or absence of F. limonia extract or marmesin. Plasma activity levels of AST, ALT, bilirubin, alkaline phosphatase, protein, hepatic antioxidants, lipid peroxidation and histopathological evaluations were carried out in rats treated with CCl4 alone or co-supplemented with F. limonia extract or marmesin in a dose-dependent manner. Key findings In-vitro co-supplementation of F. limonia methanolic extract or marmesin significantly minimized alteration in levels of AST and ALT and improved cell viability. Oral administration of F. limonia methanolic extract or marmesin significantly prevented CCl4-induced elevation in the plasma markers of hepatic damage and hepatic lipid peroxidation and a decrease in hepatic antioxidants. In-vivo hepatoprotective potential of F. limonia methanolic extract and marmesin was evident from the minimal alterations in the histoarchitecture of liver. Conclusions This has been the first scientific report on the hepatoprotective potential of F. limonia root bark methanolic extract and marmesin. [ABSTRACT FROM AUTHOR]

We used solvent extractions, SiO2 column chromatographies, and HPLC to isolate from the bark of Thanakha ( Hesperethusa crenulata L) an active crystalline compound for absorbing UV-A radiation (320 to 380 nm). Analyses of low-and high-resolution FAB-MS revealed a compound, named marmesin, with a formula of C14H14O4 and a molecular mass of 246. To determine its chemical structure, we conducted 300 MMz NMR analyses using various probes,1H,13C, and DEPT13C. Our NMR data showed a structure of 2,3-dihydro-2(1 -hydroxy-1 -methylethyl)-furanocoumarin. This active compound contains UV-absorbing chromophores, an aromatic ring, a double bond at C3-C4, and a carbonyl at C2. Its λmax is 335 nm, indicating that marmesin could be commercially useful as a natural UV-A-filtering product [ABSTRACT FROM AUTHOR]