Fungal natural alkaloid schizocommunin activates the aryl hydrocarbon receptor pathway

Diversity of substrate type, ethnomycology, mineral composition, proximate, and phytochemical compounds of the Schizopyllum commune Fr. in the area along Palu-Koro Fault, Central Sulawesi, Indonesia

Schizophyllum commune Fr. is a wild macro fungus species, which is often used as a food source by the indigenous Kaili tribe along the Palu-Koro fault, Central Sulawesi, Indonesia. This fungus has a wide variety in terms of the weathered wood substrate as a place to grow and is found in almost all types of ecosystems. Although its diversity has been investigated, there is no identification of the weathered wood type as a substrate for growth. Some communities in Indonesia have not also known its potential and benefits. Therefore, this research aims to determine the wood type that grows S. commune fungus, ethnomycology, mineral composition, proximate, and phytochemical compounds. It was carried out using the descriptive explanatory approach and the fungi location as well as wood substrate sampling, was determined through the purposive sampling technique in forest areas, agroforestry, and community gardens along the Palu-Koro fault, Central Sulawesi. The samples of unknown wood types were through the collection of tree parts, namely twigs, leaves, flowers, and fruits, which were brought to Herbarium Celebense, Tadulako University for identification. Analysis of mineral content, proximate, and fungal phytochemical compounds was carried out based on the method according to the existing protocol. The results showed that 92 types of rotted wood found where the fungus S. commune grew, belonged to 36 families. The nutritional content is also good, although it varies based on the type of wood growing media. Therefore, it can be used and processed into various health-beneficial food products. This showed that domestication of the fungus needs to be carried out to support its commercialization as food and medicine in the future.

Curcumin Suppresses the Lipid Accumulation and Oxidative Stress Induced by Benzo[a]pyrene Toxicity in HepG2 Cells

Benzo[a]pyrene (B[a]P) is a potentially hepatotoxic group-1 carcinogen taken up by the body through ingestion of daily foods. B[a]P is widely known to cause DNA and protein damages, which are closely related to cell transformation. Accordingly, studies on natural bioactive compounds that attenuate such chemical-induced toxicities have significant impacts on public health. This study aimed to uncover the mechanism of curcumin, the major curcuminoid in turmeric (Curcuma longa), in modulating the lipid accumulation and oxidative stress mediated by B[a]P cytotoxicity in HepG2 cells. Curcumin treatment reduced the B[a]P-induced lipid accumulation and reactive oxygen spicies (ROS) upregulation and recovered the cell viability. Cytochrome P450 family 1 subfamily A polypeptide 1 (CYP1A1) and Cytochrome P450 subfamily B polypeptide 1 (CYP1B1) downregulation resulting from decreased aryl hydrocarbon receptor (AhR) translocation into nuclei attenuated the effects of B[a]P-induced lipid accumulation and repressed cell viability, respectively. Moreover, the curcumin-induced reduction in ROS generation decreased the nuclear translocation of Nuclear factor erythroid-2-related factor 2 (Nrf2) and the expression of phase-II detoxifying enzymes. These results indicate that curcumin suppresses B[a]P-induced lipid accumulation and ROS generation which can potentially induce nonalcoholic fatty liver disease (NAFLD) and can shed a light on the detoxifying effect of curcumin.

[Synthetic Study of Polycyclic Natural Products Based on Development of New Strategy]

On the occasion of receiving the Pharmaceutical Society of Japan Award 2020, I explained our research activities on the total syntheses of polycyclic alkaloids as an invited review. The structure of lundurine B, which has an unstable cyclopropane fused indoline skeleton, was proved firstly by the total synthesis. I also describe the total syntheses of optically active lundurine B and rapidilectine B utilizing asymmetric desymmetrization of the spiro intermediate. We developed an intramolecular bond formation reaction between the 2-position of the furan ring to the iminium cation (furane-iminium cation cyclization) to synthesize manzamine alkaloids. The reaction was applied to the total synthesis of the core skeleton of nakadomarin A and ircinal A. A ring-closing metathesis reaction effectively applied to the synthesis of medium and large heterocyclic rings containing the cis double bond found in the structures of nakadomarin A and ircinal A. The total synthesis of schizocommunin, a metabolite of Schizophyllum commune isolated from a patient with human allergenic bronchopulmonary mycosis, was accomplished. We could correct the error in the proposed structure by total synthesis of the natural product. A part of the mechanism of cytotoxicity expression was clarified using newly synthesized shizocommunin.

Indole scaffolds as a promising class of the aryl hydrocarbon receptor ligands

The aryl hydrocarbon receptor (AhR), deemed initially as a xenobiotic sensor, plays multiple physiological roles and is involved in various pathophysiological processes and many diseases' etiology. Therefore, the therapeutic and chemopreventive targeting of AhR is a fundamental issue. To date, thousands of structurally diverse ligands of AhR have been identified. The bottleneck in targeting the AhR is that it is a Janus-faced player with beneficial vs. harmful effects in the ligand-specific context. A distinct structural class of the AhR ligands is those with indole-based scaffolds. The present review summarizes the knowledge on the existing indole-derived AhR ligands, comprising natural and dietary compounds, synthetic compounds including clinically used drugs, endogenous intermediary metabolites, and catabolites produced by human microbiota. The examples of novel, indole ring containing, rational design based AhR ligands are presented. The molecular, in vitro, and in vivo effects are described.

Advances in deep eutectic solvents and water: applications in metal- and biocatalyzed processes, in the synthesis of APIs, and other biologically active compounds

This review highlights recent advances in metal- and biocatalyzed transformations, in the synthesis of APIs and other biologically active compounds, when employing deep eutectic solvents and water as environmentally responsible solvents.