beta-Eudesmol as an antidote for intoxication from organophosphorus anticholinesterase agents

Metabolite profiling of Borneo's Gonystylus bancanus through comprehensive extraction from various polarity of solvents

Gonystylus bancanus wood or ramin wood has been generally known as a source of agarwood (gaharu) bouya, a kind of agarwood inferior type, or under the exported trading name of aetoxylon oil. The massive exploitation of ramin wood is causing this plant's extinction and putting it on Appendix II CITES and IUCN Red List of Threatened Species. To date, no scientific publication concerns the chemical exploration of G. bancanus wood and preserving this germplasm through its metabolite profiling. Therefore, research focused on chemical components profiling of G. bancanus is promised. This research is aimed to explore metabolomics and analyze the influence of solvent polarities on the partitioning of metabolites in G. bancanus wood. A range of solvents in different polarities was applied to provide comprehensive extraction of metabolites in G. bancanus wood. Moreover, a hydrodistillation was also carried out to extract the volatile compounds despite the non-volatile ones. LCMS and GCMS analyses were performed to identify volatile and non-volatile components in the extracts and essential oil. Multivariate data analysis was processed using Principal Component Analysis (PCA) and agglomerative hierarchical clustering. 142 metabolites were identified by LCMS analysis, while 89 metabolites were identified by GCMS analysis. Terpenoids, flavonoids, phenyl propanoids, and saccharides are some major compound classes available from LCMS data. Oxygenated sesquiterpenes, especially 10-epi-γ-eudesmol, and β-eudesmol, are the major volatile components identified from GCMS analysis. PCA of LCMS analysis demonstrated that PC1 discriminated two clusters: essential oil, dichloromethane, and n-hexane extracts were in the positive quadrant, while methanol and ethyl acetate extracts were in the negative quadrant. Three-dimensional analysis of GCMS data revealed that n-hexane extract was in the superior quadrant, and its composition can be significantly distinguished from other extracts and essential oil. G. bancanus wood comprises valuable metabolites, i.e., terpenoids, which benefit the essential oil industry. Comprehensive extraction by performing solvents in different polarities on G. bancanus wood could allow exploration of fully extracted metabolites, supported by the exhibition of identified metabolites from LCMS and GCMS analysis.

Molecular Diversity from Arid-Land Plants: Valorization of Terpenes and Biotransformation Products

Asteraceae plants from arid lands are a source of biomass, resin and latex rich in terpenoids with diverse biological effects. Thirty-six previously isolated terpenes, comprising sesquiterpenes, diterpenes, triterpenes and quassinoids, isolated from arid-land plants and a series of metabolites from the biotransformation of some lead compounds were evaluated against insect pests (Spodoptera littoralis, Leptinotarsa decemlineata, Myzus persicae and Rhopalosiphum padi), cells (insect, hamster, murine and human tumoral cells) and parasites (Trypanosoma cruzi and Leishmania infantum). Among the insecticidal sesquiterpenes, maalian-1α,8α-diol (12) and γ-eudesmol (17) were antifeedant against L. decemlineata, M. persicae and cytotoxic to Sf9 insect cells, and (-)-maali-3-en-8α-ol (10), (+)-maaliane-5α,8α,9α-triol (11), chrysothame (31) and holacanthone (35) were antifeedant against S. littoralis. The parasite L. infantum was slightly more sensitive than T. cruzi to the test compounds (39 % vs. 33 % of active compounds) with compound 17 and the biotransformed diterpene 27 being antiparasitic to L. infantum, with no cytotoxic effects on mammalian cells. Moreover, sesquiterpenes 3 and 17, and grindelane diterpenes 22, 23 and 26 showed selective activity against chemoresistant human colon, cervical and melanoma cancer cells. Thus, considering our results, the best candidates for future studies are compounds 17 and 3, due to their activity on insect pests, parasites (17) and tumoral cells (3, 17, 22, 23 and 26).

β-Eudesmol, an oxygenized sesquiterpene, stimulates appetite via TRPA1 and the autonomic nervous system

Transient receptor potential ankyrin 1 (TRPA1) is a calcium-permeable non-selective cation channel, which is activated by various noxious or irritant substances in nature. TRPA1 activators have been generally recognized as noxious, however, foods and beverages containing TRPA1 activators are preferably consumed; the reasons for this discrepancy are not well understood. We demonstrate that TRPA1 is involved in the stimulatory appetite control mechanism. β-Eudesmol is an oxygenated sesquiterpene contained in medicinal or edible plants which activates TRPA1. Oral administration of β-eudesmol brought significant increments in food intake in rats and elevated plasma ghrelin levels. Gastric vagal nerve activity (GVNA) has been reported to affect feeding behavior. In vivo electrophysiological measurement of GVNA revealed that oral-ingestion of β-eudesmol significantly increased GVNA. This GVNA elevation was eliminated by TRPA1 inhibitor (HC-030031) treatment prior to β-eudesmol administration. The physiological effects of β-eudesmol, for example, incremental increase in food intake, ghrelin elevation and activation of GVNA, were significantly reduced in TRPA1 knockout rats. Our results indicated that β-eudesmol stimulates an increase in appetite through TRPA1, and suggests why TRPA1 activator containing foods and beverages are preferably consumed.

Synthesis and Storage Stability of Diisopropylfluorophosphate

Diisopropylfluorophosphate (DFP) is a potent acetylcholinesterase inhibitor commonly used in toxicological studies as an organophosphorus nerve agent surrogate. However, LD₅₀ values for DFP in the same species can differ widely even within the same laboratory, possibly due to the use of degraded DFP. The objectives here were to identify an efficient synthesis route for high purity DFP and assess the storage stability of both the in-house synthesized and commercial source of DFP at the manufacturer-recommended storage temperature of 4°C, as well as −10°C and −80°C. After 393 days, the commercial DFP stored at 4°C experienced significant degradation, while only minor degradation was observed at −10°C and none was observed at −80°C. DFP prepared using the newly identified synthesis route was significantly more stable, exhibiting only minor degradation at 4°C and none at −10°C or −80°C. The major degradation product was the monoacid derivative diisopropylphosphate, formed via hydrolysis of DFP. It was also found that storing DFP in glass containers may accelerate the degradation process by generating water in situ as hydrolytically generated hydrofluoric acid attacks the silica in the glass. Based on the results here, it is recommended that DFP be stored at or below −10°C, preferably in air-tight, nonglass containers.