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BACKGROUND Gnetol is a stilbene whose characterization and bioactivity have been poorly studied. It shares some bioactivities with its analogue resveratrol, such as anti‐inflammatory, anti‐thrombotic, cardioprotective and anti‐cancer activities. However, the low solubility of stilbenes may limit their potential applications in functional foods. Encapsulation in cyclodextrins could be a solution. RESULTS: The antioxidant activity of gnetol was evaluated by 2,2′‐azino‐bis(3‐ethylbenzothiazoline‐6‐sulfonic acid) radical cation and ferric reducing antioxidant power methods (Trolox equivalents 13.48 μmol L−1 and 37.08 μmol L−1 respectively at the highest concentration) and it was higher than that of resveratrol, and depending on the method, similar or higher to that of oxyresveratrol. Spectrophotometric and spectrofluorimetric characterization of gnetol is published for the first time. Moreover, its water solubility was determined and improved almost threefold after its molecular encapsulation in cyclodextrins, as well as its stability after storage for a week. A physicochemical and computational study revealed that cyclodextrins complex gnetol in a 1:1 stoichiometry, with better affinity for like 2‐hydroxypropyl‐β‐cyclodextrin (KF = 4542.90 ± 227.15 mol−1 L). Temperature and pH affected the encapsulation constants. CONCLUSION: These results could increase interest of gnetol as an alternative to the most studied stilbene, resveratrol, as well as aid in the development of more stable inclusion complexes that improve its aqueous solubility and stability so that it can be incorporated into functional foods. © 2022 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

BACKGROUND 2‐Phenylethanol (PEA) is a higher aromatic alcohol with a rose‐like odor, which is used in several industries. Although PEA can be synthesized, consumers are increasingly concerned about the toxicity of chemically synthesized products, and prefer natural aroma compound. PEA occurs naturally in the environment but concentrations are too low to justify extraction. RESULTS: The present study offers a novel biological source of PEA: the filamentous fungi Monochaetinula geoffroeana. We report the highest recorded yield of PEA of fungal origin to date: 6.52 g L−1. The volatility and low water solubility of PEA can affect its use in many industries, for which reason complexation studies of PEA and cyclodextrins were carried out using the phase solubility technique. PEA formed 1:1 stoichiometric inclusion complexes with natural and modified CDs, the highest encapsulation constant being obtained with MβCD (K1:1 = 299.88 L mol−1). The complexation process significantly increased the water solubility of PEA. A computational study showed a high degree of correlation between computed scores and experimental values. Furthermore, this study reports the role of salicylic acid as an effective elicitor for improved PEA production by the studied fungi. Supplementation with 10 μmol L−1 salicylic acid increased PEA production from 6.52 to 10.54 g L−1. CONCLUSION: The best treatment to enhance PEA production by M. geoffroeana under laboratory conditions was to use salicylic acid 10 μmol L−1. Due to the commercial importance of PEA, further investigation is needed to improve PEA production by M. geoffroeana and to optimize culture conditions in order to standardize yields. © 2021 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Introduction Several authors have reported on the different bioactivities of methyl jasmonate (MeJA) stereoisomers. However, no simple, precise and cheap method for separating and identifying them using reversed-phase high performance liquid chromatography (RP-HPLC) has been developed. Objective (1) To create a simple, precise and cheap method for separating and identifying the four stereoisomers present in commercial racemic mixtures of MeJA and (2) to identify the four stereoisomers using molecular docking techniques and coinjection. Materials and Methods - RP-HPLC using a 250 mm C18 column and different proportions of cyclodextrins (CDs) and organic solvents was applied to a commercial sample of racemic MeJA. Results The results show that the best conditions for separating the MeJA stereoisomers are: 20% methanol in the mobile phase, a temperature of 45 °C and a 16 mM concentration of methyl- β-cyclodextrin (M-β-CD). A simple C18 250 mm column and a flow rate of 1.25 mL/min were used. The reduction in the retention time of MeJA observed when M-β-CD is added to the mobile phases was used to determine the complexation constants of the guest/CD complex and compared with the obtained when other CDs were used. The KF for M-β-CD (117.49 ± 5.9 1/M) was obtained with a 1:1 stoichiometry. The four stereoisomers were identified by molecular docking techniques and coinjection of a commercially available rosemary essential oil. Conclusion The new method identified and classified the four stereoisomers of MeJA in the following ordination: (−)epiMeJA, (−)MeJA; (+)MeJA and (+)epiMeJA. These results could be used to improve the elicitation of cell cultures with only the best isomer. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]