arachidin-3 and arachidin-1

Prenylated stilbenoids such as arachidin-1 and arachidin-3 are stilbene derivatives that exhibit multiple pharmacological activities. We report an elicitation strategy using different combinations of cyclodextrin, hydrogen peroxide, methyl jasmonate and magnesium chloride to increase arachidin-1 and arachidin-3 production in peanut hairy root cultures. The treatment of hairy root cultures with cyclodextrin with hydrogen peroxide selectively enhanced arachidin-1 yield (132.6 ± 20.4 mg/L), which was 1.8-fold higher than arachidin-3. Similarly, cyclodextrin combined with methyl jasmonate selectively enhanced arachidin-3 yield (178.2 ± 6.8 mg/L), which was 5.5-fold higher than arachidin-1. Re-elicitation of the hairy root cultures further increased the levels of arachidin-1 and arachidin-3 by 24% and 42%, respectively. The ethyl acetate extract of the culture medium was consecutively fractionated by normal- and reversed-phase column chromatography, followed by semi-preparative HPLC purification on a C18 column to yield arachidin-1 with a recovery rate of 32% and arachidin-3 with a recovery rate of 39%, both at higher than 95% purity. This study provided a sustainable strategy to produce high-purity arachidin-1 and arachidin-3 using hairy root cultures of peanuts combined with column chromatography and semi-preparative HPLC.

Topics: Acetates; Arachis; Cyclodextrins; Cyclopentanes; Hemiterpenes; Hydrogen Peroxide; Magnesium Chloride; Oxylipins; Plant Roots; Stilbenes

Aspergillus flavus is a soil fungus that commonly invades peanut seeds and often produces carcinogenic aflatoxins. Under favorable conditions, the fungus-challenged peanut plant produces and accumulates resveratrol and its prenylated derivatives in response to such an invasion. These prenylated stilbenoids are considered peanut antifungal phytoalexins. However, the mechanism of peanut-fungus interaction has not been sufficiently studied. We used pure peanut stilbenoids arachidin-1, arachidin-3, and chiricanine A to study their effects on the viability of and metabolite production by several important toxigenic Aspergillus species. Significant reduction or virtually complete suppression of aflatoxin production was revealed in feeding experiments in A. flavus, Aspergillus parasiticus, and Aspergillus nomius. Changes in morphology, spore germination, and growth rate were observed in A. flavus exposed to the selected peanut stilbenoids. Elucidation of the mechanism of aflatoxin suppression by peanut stilbenoids could provide strategies for preventing plant invasion by the fungi that produce aflatoxins.

Topics: Aflatoxins; Arachis; Aspergillus; Hemiterpenes; Sterigmatocystin; Stilbenes

Peanut (Arachis hypogaea) produces stilbenoids upon exposure to abiotic and biotic stresses. Among these compounds, the prenylated stilbenoids arachidin-1 and arachidin-3 have shown diverse biological activities with potential applications in human health. These compounds exhibit higher or novel biological activities in vitro when compared to their nonprenylated analogues piceatannol and resveratrol, respectively. However, assessment of these bioactivities in vivo has been challenging because of their limited availability. In this study, hairy root cultures of peanut were induced to produce stilbenoids upon treatment with elicitors. Co-treatment with 100 μM methyl jasmonate (MeJA) and 9 g/L methyl-β-cyclodextrin (CD) led to sustained high levels of resveratrol, piceatannol, arachidin-1, and arachidin-3 in the culture medium when compared to other elicitor treatments. The average yields of arachidin-1 and arachidin-3 were 56 and 148 mg/L, respectively, after co-treatment with MeJA and CD. Furthermore, MeJA and CD had a synergistic effect on resveratrol synthase gene expression, which could explain the higher yield of resveratrol when compared to treatment with either MeJA or CD alone. Peanut hairy root cultures were shown to be a controlled and sustainable axenic system for the production of the diverse types of biologically active stilbenoids.

Topics: Acetates; Arachis; beta-Cyclodextrins; Cell Culture Techniques; Culture Media; Cyclopentanes; Gene Expression Regulation, Plant; Hemiterpenes; Oxylipins; Plant Growth Regulators; Plant Proteins; Plant Roots; Resveratrol; Stilbenes

One new stilbene derivative (3,5,3'-trihydroxy-4'-methoxy-5'-isopentenylstilbene, MIP) and two new stilbene dimers (arahypin-11 and arahypin-12) together with three known stilbenoids (arachidin-1, arachidin-3, and SB-1) were isolated from black skin peanut seeds challenged by the fungal strain Rhizopus oligoporus . The structures of the three new compounds were elucidated by analysis of HRESIMS, UV, 1D and 2D NMR spectra. The antiadipogenic and cytotoxic effects of the isolated compounds were investigated using 3T3-L1 cells at a concentration range of 1-10 μM. Among the compounds tested, arachidin-1 inhibited the 3T3-L1 adipocyte differentiation dose-dependently, whereas arahypin-11 and arahypin-12 exhibited significant cytotoxicity in 3T3-L1 preadipocytes.

Topics: 3T3-L1 Cells; Adipocytes; Adipogenesis; Animals; Arachis; Cell Differentiation; Cell Survival; Chromatography, High Pressure Liquid; Flavonoids; Fungi; Hemiterpenes; Mice; Seeds; Stilbenes; Stress, Physiological

The therapeutic promise of trans-resveratrol (tRes) is limited by poor bioavailability following rapid metabolism. We hypothesise that trans-arachidin-1 (tA1) and trans-arachidin-3 (tA3), peanut hairy root-derived isoprenylated analogs of tRes, will exhibit slower metabolism/enhanced bioavailability and retain biological activity via cannabinoid receptor (CBR) binding relative to their non-prenylated parent compounds trans-piceatannol (tPice) and tRes, respectively.. The activities of eight human UDP-glucuronosyltransferases (UGTs) toward these compounds were evaluated. The greatest activity was observed for extrahepatic UGTs 1A10 and 1A7, followed by hepatic UGTs 1A1 and 1A9. Importantly, an additional isoprenyl and/or hydroxyl group in tA1 and tA3 slowed overall glucuronidation. CBR binding studies demonstrated that all analogs bound to CB1Rs with similar affinities (5-18 µM); however, only tA1 and tA3 bound appreciably to CB2Rs. Molecular modelling studies confirmed that the isoprenyl moiety of tA1 and tA3 improved binding affinity to CB2Rs. Finally, although tA3 acted as a competitive CB1R antagonist, tA1 antagonised CB1R agonists by both competitive and non-competitive mechanisms.. Prenylated stilbenoids may be preferable alternatives to tRes due to increased bioavailability via slowed metabolism. Similar structural analogs might be developed as novel CB therapeutics for obesity and/or drug dependency.

Topics: Animals; Binding, Competitive; Biological Availability; CHO Cells; Chromatography, High Pressure Liquid; Cricetinae; Glucuronosyltransferase; Hemiterpenes; Humans; Kinetics; Mass Spectrometry; Metabolic Detoxication, Phase II; Models, Molecular; Prenylation; Receptors, Cannabinoid; Recombinant Proteins; Resveratrol; Stilbenes

Previously, we have shown that hairy root cultures of peanut provide a controlled, sustainable and scalable production system that can be induced to produce stilbenoids. However to leverage peanut hairy roots to study the biosynthesis of this polyphenolic biosynthetic pathway, growing conditions and elicitation kinetics of these tissue cultures must be defined and understood. To this end, a new peanut cv. Hull hairy root (line 3) that produces resveratrol and its prenylated analogues arachidin-1 and arachidin-3 upon sodium acetate-mediated elicitation was established. Two culture media were compared for impact on root growth and stilbenoid biosynthesis/secretion. The levels of ammonium, nitrate, phosphate and residual sugars were monitored along growth and elicitation period. A modified MS (MSV) medium resulted in higher root biomass when compared to B5 medium. The stilbenoid profile after elicitation varied depending on the age of the culture (6, 9, 12, and 15-day old). After elicitation at day 9 (exponential growth in MSV medium), over 90% of the total resveratrol, arachidin-1 and arachidin-3 accumulated in the medium. Our studies demonstrate the benefits of the hairy root culture system to study the biosynthesis of stilbenoids including valuable prenylated polyphenolic compounds.

Topics: Arachis; Cells, Cultured; Culture Media; Hemiterpenes; Plant Extracts; Plant Roots; Sodium Acetate; Stilbenes; Tissue Culture Techniques