MyMedR

Displaying all 4 publications

Abstract:

Sort:

Fulltext Potential Anti-Acetylcholinesterase Activity of Cassia timorensis DC

Azman NAN, Alhawarri MB, Rawa MSA, Dianita R, Gazzali AM, Nogawa T, et al.

Molecules, 2020 Oct 04;25(19).
PMID: 33020403 DOI: 10.3390/molecules25194545

Seventeen methanol extracts from different plant parts of five different Cassia species, including C. timorensis, C. grandis, C. fistula, C. spectabilis, and C. alata were screened against acetylcholinesterase (AChE). C. timorensis extracts were found to exhibit the highest inhibition towards AChE whereby the leaf, stem, and flower methanol extracts showed 94-97% inhibition. As far as we are aware, C. timorensis is one of the least explored Cassia spp. for bioactivity. Further fractionation led to the identification of six compounds, isolated for the first time from C. timorensis: 3-methoxyquercetin (1), benzenepropanoic acid (2), 9,12,15-octadecatrienoic acid (3), β-sitosterol (4), stigmasterol (5), and 1-octadecanol (6). Compound 1 showed moderate inhibition towards AChE (IC50: 83.71 μM), while the other compounds exhibited poor to slightly moderate AChE inhibitory activity. Molecular docking revealed that the methoxy substitution of 1 formed a hydrogen bond with TYR121 at the peripheral anionic site (PAS) and the hydroxyl group at C5 formed a covalent hydrogen bond with ASP72. Additionally, the OH group at the C3' position formed an interaction with the protein at the acyl pocket (PHE288). This possibly explains the activity of 1 in blocking the entry of acetylcholine (ACh, the neurotransmitter), thus impeding the hydrolysis of ACh.
Anti-Cholinesterase Activity of Chalcone Derivatives: Synthesis, In Vitro Assay and Molecular Docking Study

Riswanto FDO, Rawa MSA, Murugaiyah V, Salin NH, Istyastono EP, Hariono M, et al.

Med Chem, 2021;17(5):442-452.
PMID: 31808389 DOI: 10.2174/1573406415666191206095032

BACKGROUND: Chalcones, originated from natural product, have been broadly studied their biological activity against various proteins which at the molecular level, are responsible for the progress of the diseases in cancer (e.g. kinases), inflammation (oxidoreductases), atherosclerosis (cathepsins receptor), and diabetes (e.g. α-glucosidase).
OBJECTIVE: Here we synthesize 10 chalcone derivatives to be evaluated their in vitro enzymatic inhibition activity against acetylcholinesterase (AChE) and butyrylcholinesterase (BChE).
METHODS: The synthesis was carried out using Claissen-Schimdt condensation and the in vitro assay was conducted using Ellman Method.
RESULTS: Compounds 2b and 4b demonstrated as the best IC50 of 9.3 μM and 68.7 μM respectively, towards AChE and BChE inhibition. Molecular docking studies predicted that this activity might be due to the interaction of the chalcones with important amino acid residues in the binding site of AChE such as SER200 and in that of BChE, such as TRP82, SER198, TRP430, TYR440, LEU286 and VAL288.
CONCLUSION: Chalcone can be used as the scaffold for cholinesterase inhibitor, in particularly either fluorine or nitro group to be augmented at the para-position of Ring B, whereas the hydrophobic chain is necessary at the meta-position of Ring B.
A new peptaibol, RK-026A, from the soil fungus Trichoderma sp. RK10-F026 by culture condition-dependent screening

Rawa MSA, Nogawa T, Okano A, Futamura Y, Nakamura T, Wahab HA, et al.

Biosci Biotechnol Biochem, 2021 Jan 07;85(1):69-76.
PMID: 33577647 DOI: 10.1093/bbb/zbaa051

A new peptaibol, RK-026A (1) was isolated from a fungus, Trichoderma sp. RK10-F026, along with atroviridin B (2), alamethicin II (3), and polysporin B (4) as a cytotoxic compound, which was selected by principal component analysis of the MS data from 5 different culture conditions. The structure of 1 was determined as a new atroviridin B derivative containing Glu at the 18th residue instead of Gln by NMR and HR-MS analyses including the investigation of detailed MS/MS fragmentations. 1 showed cytotoxicity toward K562 leukemia cells at an IC50 value of 4.1 µm.
Zealpeptaibolin, an 11-mer cytotoxic peptaibol group with 3 Aib-Pro motifs isolated from Trichoderma sp. RK10-F026

Rawa MSA, Nogawa T, Okano A, Futamura Y, Wahab HA, Osada H

J Antibiot (Tokyo), 2021 08;74(8):485-495.
PMID: 34163024 DOI: 10.1038/s41429-021-00429-y

Six new 11-mer peptaibols designed as zealpeptaibolins, A - F were isolated from the soil fungus, Trichoderma sp. RK10-F026, based on the principal component analysis of the MS data from five different culture compositions. Previously, 20-mer peptaibols from the same fungal strain were identified; 11-mer peptaibols in contrast were discovered from a different culture condition, signifying peptaibol production was culture condition-dependent. These peptaibols contained three Aib-Pro motifs in the sequence. The structures were established by NMR and HR-MS experiments including detailed MS/MS fragmentations. The absolute configurations were determined by Marfey's analysis. Zealpeptaibolin F exhibited the strongest cytotoxicity toward K562 leukemia cells with an IC50 value of 0.91 µM.