14-Methylpentadecano-15-lactone (muscolide): a new macrocyclic lactone from the oil of Angelica archangelica L

Comprehensive identification of terpene synthase genes and organ-dependent accumulation of terpenoid volatiles in a traditional medicinal plant Angelica archangelica L

Angelica archangelica L. is a traditional medicinal plant of Nordic origin that produces an unusual amount and variety of terpenoids. The unique terpenoid composition of A. archangelica likely arises from the involvement of terpene synthases (TPSs) with different specificities, none of which has been identified. As the first step in identifying TPSs responsible for terpenoid chemodiversity in A. archangelica, we produced a transcriptome catalogue using the mRNAs extracted from the leaves, tap roots, and dry seeds of the plant; 11 putative TPS genes were identified (AaTPS1-AaTPS11). Phylogenetic analysis predicted that AaTPS1-AaTPS5, AaTPS6-AaTPS10, and AaTPS11 belong to the monoterpene synthase (monoTPS), sesquiterpene synthase (sesquiTPS), and diterpene synthase clusters, respectively. We then performed in vivo enzyme assays of the AaTPSs using recombinant Escherichia coli systems to examine their enzymatic activities and specificities. Nine recombinant enzymes (AaTPS2-AaTPS10) displayed TPS activities with specificities consistent with their phylogenetics; however, AaTPS5 exhibited a strong sesquiTPS activity along with a weak monoTPS activity. We also analyzed terpenoid volatiles in the flowers, immature and mature seeds, leaves, and tap roots of A. archangelica using gas chromatography-mass spectrometry; 14 monoterpenoids and 13 sesquiterpenoids were identified. The mature seeds accumulated the highest levels of monoterpenoids, with β-phellandrene being the most prominent. α-Pinene and β-myrcene were abundant in all organs examined. The in vivo assay results suggest that the AaTPSs functionally identified in this study are at least partly involved in the chemodiversity of terpenoid volatiles in A. archangelica.

Root symbionts alter herbivore-induced indirect defenses of tomato plants by enhancing predator attraction

Beneficial root microbes are among the most frequently used biocontrol agents in cropping systems, since they have been shown to promote plant growth and crop yield. Moreover, they are able to enhance protection against pathogens and insect herbivores by activating plant resistance mechanisms. Plant defense responses against herbivorous insects include the induction of metabolic pathways involved in the synthesis of defense-related metabolites. These metabolites include volatile organic compounds (VOCs), which attract natural enemies of the herbivores as a form of indirect resistance. Considering that beneficial root microbes may affect direct herbivore resistance, we hypothesized that also indirect resistance may be affected. We tested this hypothesis in a study system composed of tomato, the arbuscular mycorrhizal fungus Rhizophagus irregularis, the growth-promoting fungus Trichoderma harzianum, the generalist chewing herbivore Spodoptera exigua and the omnivorous predator Macrolophus pygmaeus. Using a Y-tube olfactometer we found that M. pygmaeus preferred plants with S. exigua herbivory, but microbe-inoculated plants more than non-inoculated ones. We used a targeted GC-MS approach to assess the impact of beneficial microbes on the emission of volatiles 24 h after herbivory to explain the choice of M. pygmaeus. We observed that the volatile composition of the herbivore-infested plants differed from that of the non-infested plants, which was driven by the higher emission of green leaf volatile compounds, methyl salicylate, and several monoterpenes and sesquiterpenes. Inoculation with microbes had only a marginal effect on the emission of some terpenoids in our experiment. Gene expression analysis showed that the marker genes involved in the jasmonic and salicylic acid pathways were differentially expressed in the microbe-inoculated plants after herbivory. Our results pinpoint the role of root symbionts in determining plant-microbe-insect interactions up to the third trophic level, and elucidates their potential to be used in plant protection.

Determination of volatiles, antioxidant activity, and polyphenol content in the postharvest waste of Ocimum basilicum L

The treatment of postharvest wastes is an integral part of the food value chain. Therefore, Ocimum basilicum L. residues were dried in an oven and a microwave. Volatiles were extracted using hydrodistillation, headspace solid-phase microextraction (HS-SPME) and then analyzed by Gas Chromatography-Mass Spectrometry (GC-MS). Thirty volatiles were identified in raw material, with β-linalool, methyleugenol, methylcinnamate, and estragole predominating. Meanwhile, 24 and 18 volatiles were detected in the oven- and microwave-dried samples, with a significant decrease of methyleugenol content. The highest radical scavenging ability and total phenolic content were achieved for microwaved wastes using photochemiluminescence, DPPH, and Folin-Ciocalteu test. Moreover, 8 phenolic acids and 9 flavonoids were identified in the LC-MS/MS analysis, with significant contents of rosmarinic acid and luteolin (1042.45 and 11.68 µg/g of dry matter, respectively) in the microwaved basil. This experiment pointed out that microwaved basil wastes could be re-used in the food, pharmacy and/or cosmetic industries.

Volatile Compounds, Sensory Profile and Phenolic Compounds in Fermented Rice Bran

Rice bran (RB), a by-product of the rice milling process, is a rich source of bioactive compounds. Current studies have suggested that fermentation can enhance the bioactivities of RB. This study is aimed to analyse the volatile compounds and sensory profile of fermented RB from two cultivars (Inpari 30 and Cempo Ireng) that are well-known in Indonesia, as well as to measure total phenolic content (TPC) and antioxidant activity. Volatile compounds of fermented RB were analyzed using gas chromatography-mass spectrometry combined with headspace-solid phase microextraction. The optimum TPC and antioxidant activity were observed after 72 h fermentation of RB. The 55 volatile compounds were identified in fermented and non-fermented RB. They were classified into alcohols, aldehydes, acids, ketones, phenols, esters, benzene, terpenes, furans, lactone, pyridines, pyrazines, and thiazoles. Volatile compounds were significantly different among the varieties. The sensory analysis showed that the panelists could differentiate sensory profiles (color, taste, flavor, and texture) between the samples. Fermentation can enhance the acceptance of RB. These studies may provide opportunities to promote the production of fermented RB as a functional ingredient with enhanced bioactivity for health promotion.

Validation of Qualitative Broth Volatilization Checkerboard Method for Testing of Essential Oils: Dual-Column GC–FID/MS Analysis and In Vitro Combinatory Antimicrobial Effect of Origanum vulgare and Thymus vulgaris against Staphylococcus aureus in Liquid and Vapor Phases

Combinatory action of antimicrobial agents such as essential oils (EOs) show to be an effective strategy to overcome the problem with increasing antibiotic resistance of microorganisms, including Staphylococcus aureus. The objective of this study was to evaluate in vitro antimicrobial interactions between Origanum vulgare and Thymus vulgaris EOs against various S.aureus strains in both liquid and vapor phases using the broth volatilization checkerboard method. Fractional inhibitory concentrations (FICs) were determined for both liquid and vapor phases, and the composition of EOs was analyzed by gas chromatography-mass spectrometry using dual-column/dual-detector gas chromatograph. Results of oregano and thyme EOs combination showed additive effects against all S. aureus strains in both phases. In several cases, sums of FICs were lower than 0.6, which can be considered a strong additive interaction. The lowest FICs obtained were 0.53 in the liquid phase and 0.59 in the gaseous phase. Chemical analysis showed that both EOs were composed of many compounds, including carvacrol, thymol, γ-terpinene, and p-cymene. This is the first report on oregano and thyme EOs interactions against S. aureus in the vapor phase. It also confirms the accuracy of the broth volatilization checkerboard method for the evaluation of combinatory antimicrobial effects of EOs in the vapor phase.

Exploring Ecological Alternatives for Crop Protection Using Coriandrum sativum Essential Oil

Essential oils (EOs) are a natural source of active compounds with antifungal, antimycotoxigenic, and herbicidal potential, and have been successfully used in organic agriculture, instead of chemical compounds obtained by synthesis, due to their high bioactivity and the absence of toxicity. The aim of this study was to highlight the importance of Coriandrum sativum essential oil (CEO) as a potential source of bioactive constituents and its applications as an antifungal and bioherbicidal agent. The CEO was obtained by steam distillation of coriander seeds and GC-MS technique was used to determine the chemical composition. Furthermore, in vitro tests were used to determine the antifungal potential of CEO on Fusarium graminearum mycelia growth through poisoned food technique, resulting in the minimum fungistatic (MCFs) and fungicidal concentrations (MCFg). The antifungal and antimycotoxigenic effect of CEO was studied on artificially contaminated wheat seeds with F. graminearum spores. Additionally, the herbicidal potential of CEO was studied by fumigating monocotyledonous and dicotyledonous weed seeds, which are problematic in agricultural field crops in Romania. The in vitro studies showed the antifungal potential of CEO, with a minimum concentration for a fungistatic effect of 0.4% and the minimum fungicidal concentration of 0.6%, respectively. An increase in the antifungal effects was observed in the in vivo experiment with F. graminearum, where a mixture of CEO with Satureja hortensis essential oil (SEO) was used. This increase is attributed to the synergistic effect of both EOs. Moreover, the synthesis of deoxynivalenol (DON)-type mycotoxins was found to be less inhibited. Hence, CEO has shown an herbicidal potential on weed seeds by affecting inhibition of germination.

Herbal fertility treatments used in North America from colonial times to 1900, and their potential for improving the success rate of assisted reproductive technology

This paper serves to fill a gap in the literature regarding evidence for the use of botanical remedies in the promotion of fertility. It examines the botanical remedies that were used in North America (1492-1900) for all stages of reproduction from preconception to birth, and discusses their potential for future use with present-day infertility treatments. Each medicinal plant discussed in this paper is assessed using an ethnomedicinal methodology that entails examining the published ethnobotanical, phytochemical and pharmacological data. A few clinical trials have shown that there is potential for medicinal plants to improve the success rate of assisted reproductive technology (ART) treatment if used in an integrated manner, similar to the integrated use of traditional Chinese medicine with ART treatment. For example, research has shown that older women who become pregnant have a high miscarriage rate, and this is one area that complementary and alternative medicines can address.

Synthesis of Both Enantiomers of 12-Methyl-13-tridecanolide and 14-Methyl-15-pentadecanolide (Muscolide)

Both enantiomers of 12-methyl-13-tridecanolide{( R)-(+)-1 ( S)-(-)-1} and 14-methyl-15-pentadecanolide (muscolide) {( R)-(+)-2 ( S)-(-)-2} were synthesized from either ( S)-(+)- or ( R)-(-)-3-bromo-2-methyl-1-propanol 8 as a chiral building block.

Comparison of the toxicity of aqueous and ethanol fractions of Angelica keiskei leaf using the eye irritancy test

To determine whether aqueous and ethanol fractions of the Angelica keiskei leaf exert toxicity when used for cosmetic purposes, we performed the acute eye irritancy test. Animals were treated with sample fractions (100 mg/dose) according to standard procedure guidelines. No significant changes or damage was detected in the fraction-treated groups in terms of ocular lesions in the cornea, the size of the cornea with turbidity, swelling of the eyelid and emission discharge. However, sodium dioctyl sulfosuccinate, a positive control, induced severe toxic symptoms. Thus, aqueous and ethanol fractions of Angelica keiskei do not appear to induce acute toxicity in the eye lens, as assessed from anatomical and pathological observations in the rabbit eye. Our results collectively suggest that aqueous and ethanol fractions show promise as cosmetic ingredients that do not cause eye toxicity.

Conformational analysis of thioether musks using density functional theory

A conformational analysis of nine macrocyclic thioether musks has been carried out using molecular mechanics (MMFF), density functional theory (DFT) using both B3LYP and M06 functionals, as well as Hartree-Fock and post-Hartree-Fock (MP2) ab initio methods. 6-Thia-, 10-thia- and 4-methyl-5-thia-14-tetradecananolide, 4-thia-, 7-thia-, 11-thia- and 12-thia-15-pentadecanolide and 6-thia- and 12-thia-16-hexadecanolide were modeled. Unfortunately, there was little agreement between the computational methods at the levels of theory used in this study.