Janohigenins: Long-chain anacardic acid derivatives with neuroprotective activity from Ophiopogon japonicus seeds

Anacardic Acid Derivatives Isolated from Fungal Species Tyromyces fissilis as New Histone Acetyltransferase Inhibitors

Anacardic acid (AA) was first detected in the shells of cashew nuts, Anacardium occidentale, and is known to possess inhibitory activity against acetyltransferases. Recently, several anacardic acid derivatives (AAds) were isolated from the wild fungus, Tyromyces fissilis, which has been reported as xanthine oxidase inhibitors. In the present study, we investigated whether nine AAds function as acetyltransferase inhibitors. Screening analyses were performed by incubating the enzyme protein (P300/CBP-associated factor; PCAF) and the substrate protein (histone H1) with radioisotope-marked acetyl-CoA, showing that two of the nine derivatives, namely, AAd7 and AAd11, inhibited the acetyltransferase activity of PCAF at concentrations of 50 and 100 µM, respectively. The inhibition intensities were similar to those of the original compound, AA, and the inhibitory effects of these derivatives increased in a concentration-dependent manner. Docking simulations suggested the possibility that AA, AAd7, and AAd11 might bind the same active pocket of PCAF. These results suggest that the AAds can be used as acetyltransferase inhibitors. In contrast, there were no significant differences in the molecular structure of AA and its derivatives; however, these small differences in the functional groups on the alkyl side chain on salicylic acid reduced the acetyltransferase inhibitor activity or newly produced proteolytic activity.

Uncovering heterogeneity of anacardic acids from pistachio shells: A novel approach for structural characterization

Anacardic acids (AnAs) are important secondary metabolites that occur primarily in plants of the Anacardiaceae family, such as pistachio (Pistacia vera L.). Some AnAs have been associated with health benefits, and the position of the CC double bonds is a crucial feature of these metabolites. Herein, we propose a new strategy based on RPLC separation and detection by ESI-MS/MS, preceded by an epoxidation reaction. The procedure was applied to the green extracts of lignified pistachio shells, and a mixture of AnAs bearing alkyl chains 13:0, 15:0, and 17:1 emerged as prevailing. As positional isomers of AnA 15:1 (Δ⁸ and Δ⁶) and AnAs 17:1 (Δ¹⁰ and Δ⁸) were identified for the first time, their discovery paves the way to the systematic study of their potential health-beneficial effects. The developed method was validated and applied to quantify AnAs in pistachio ethanolic extract, showing contents higher than 10 mg/ 100 g of biomass.

Isolation of Fluorescent Benzoxazines with Neuroprotective Activity from the Olive Weevil Pimelocerus perforatus

The weevil Pimelocerus perforatus poses a serious pest problem for olive cultivation in Japan. Two new racemic fluorescent benzoxazines, designated as pimeforazine A ((±)-1) and pimeforazine B ((±)-2), were successfully isolated from P. perforatus. Their structures, including the absolute configurations of their resolved enantiomers, were determined using spectroscopic methods, single-crystal X-ray diffraction, and electronic circular dichroism calculations. The neuroprotective activity of the isolated compounds was evaluated against hydrogen peroxide-induced cellular damage in SH-SY5Y human neuroblastoma cells. Compounds (±)-1 and (±)-2 exhibited neuroprotective effects.

Electrospray ionization mass spectrometry and nuclear magnetic resonance spectroscopy data for anacardic acid derivatives

The data presented here are related to the research paper entitled “Janohigenins: Long-chain anacardic acid derivatives with neuroprotective activity from Ophiopogon japonicus seeds” (Ohta et al., 2021). In this data article, we provide electrospray ionization mass spectrometry (ESIMS) and 1D and 2D nuclear magnetic resonance (NMR) spectroscopy data of four new anacardic acid derivatives, janohigenins isolated from the seeds of Ophiopogon japonicus.