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A process involving the hydroformylation/O-acylation of propenylbenzenes with a phenolic group is described for eugenol, isoeugenol, chavicol, propenyl guaethol, 2-allylphenol, and 2-allyl-6-methylphenol. The reactions occur in parallel, under the same reaction conditions in anisole, a solvent with an impressive sustainability rank comparable to those of ethanol and water. The products contain formyl and acetoxy moieties, both established olfactory groups in flavor and fragrance industry, and present potential as new fragrance components with less allergenic properties. To the best of our knowledge, this is the first time that a one-pot process involving hydroformylation combined with further functionalization in a remote site is described.

Metabolic engineering leads to plant productivity by inducing engineered nanoparticles in the metabolites biosynthesis pathway. In the present study, β-cyclodextrin nanoparticles (β-CDNPs) were synthesized, and their physical and chemical structure was investigated using transmission electron microscopy (TEM), dynamic light scattering (DLS), and zeta potential. Afterward, we used β-CDNPs with 0, 10, 50, 100 mg/L concentrations for foliar application of the aerial parts of basil (Ocimum basilicum L c.v. Keshkeni luvelou). GC-MS was used to identify compounds. β-CDNPs foliar application with a concentration of 50 ppm stimulated growth and significantly improved the growth indexes. In the presence of β-CDNPS, phenylpropanoids concentration, phenol content, and flavonoids total content in the aerial parts of basil showed a significant difference (P ≤ 5%) compared to the control group. According to molecular analysis, eugenol O-methyltransferase (EOMT) and chavicol O-methyltransferase (CVOMT) genes expression in methyl eugenol and methyl chavicol biosynthesis pathways were significantly improved when treated with 50 ppm concentration compared to the control. Basil may show antioxidant activity when treated with different concentrations of β-CDNPs, in a dose-dependent manner. Thus, β-CDNPS may act as an inducer with their stimulating, maintaining the basil phenylpropanoids as a bio-elicitor with the potential of free radical scavenging to enhance the basil’s therapeutic and nutritional properties.

Essential oils (EOs) have drawn growing attention due to an increased risk of chemical contamination upon the application of synthetic fungicides to post-harvest fruits. This experiment investigated the antifungal activity of seven EOs at different concentrations of 0.5, 1, 2, 4, 6, 8, and 10 μL mL−1 against the fungus Botrytis cinerea in two methods of liquid and vapor phase. Besides the chemical analysis of the EOs by GC–MS, minimum fungicidal concentration, minimum inhibitory concentration, and the release of cellular material were investigated. The dominant compound in rosemary EO is camphene (33.8%), whereas 1–8 cineole (67.61%) was found to be most abundant in Eucalyptus. Cumin contained cumin aldehyde (27.14%), peppermint EO contained menthol (28.27%), and the most common compound in tarragon EO was methyl chavicol (78.74%). Limonene (63.27%) was the predominant compound in lemon EO. The highest percentage of compounds in savory EO was carvacrol (50.33). The results showed that the vapor phase was consistently more effective in fungal growth than the liquid phase effect. Savory and peppermint EOs were very influential on the growth of B. cinerea at relatively low concentrations due to the presence of dominant compounds such as menthol (28.27%) and carvacrol (50.34%). According to the comparison of the data on inhibition percentage with the control group, there was a significant enhancement in the entire liquid and vapor phases by increasing EO concentration. Generally, factors such as plant species, application method, and concentration affect EOs antifungal activity. It is concluded that the EO mechanism against B. cinerea might be due to its effect on cell membrane permeability according to the electrolytes’ leakage. Therefore, these EOs as natural antimicrobial compounds seem to be effective in preventing gray mold contamination instead of synthetic preservatives, which have several established adverse effects.

This study presented the development of such a HS–SPME–GC–MS technique, with the use of which, directly from the raw milk sample matrix, both qualitatively and quantitatively; the volatile terpenoids (α-pinene, sabinene, β-pinene, p-cymene, limonene, linalool, α-thujene, camphor, menthol, methyl chavicol, caryophyllene E, α-humulene) can be determined, derived from herbs eaten by the dairy animals by different feeding methods. Repeatability was less than 10% in the case of milk fat samples. The estimated limits of quantitation were between 2 and 16 ng/g. The lowest values were 2 ng/g for p-cymene and methyl chavicol; the highest value was 16 ng/g for caryophyllene. In the case of goat milk, the repeatability was better than 8% except for α-thujene. The estimated limits of quantitation were between 1 and 8 ng/g. The lowest values were 1 ng/g for β-pinene, p-cymene and limonene, and the highest value was 8 ng/g for linalool. In milk fat, the highest concentration was identified in caryophyllene E (470 ng/g) and α-humulene (430 ng/g), while the lowest concentration was in p-cymene (2 ng/g) and camphor (2 ng/g). In goat milk, limonene was present in all samples, but its amount varied depending on the type of consumed herb. Methyl chavicol and caryophyllene E were detected in goat’s milk only in one case. The former was detected in sage milk at 2.09 ng/g and the latter in tarragon milk at 2.28 ng/g. We have also successfully demonstrated that the feed consumed by dairy animals also affects the quality of dairy products.

Ocimum basilicum (Lamiaceae) commonly known as Sweet Basil is an aromatic plant having a controversial carcinogenic effect and is also used in the food industry. This study was designed to evaluate the chemical constituent by the chemometrics-assisted-GCMS and the antioxidant activity of the O. basilicum L. herb gathered from Sivas. Twenty-one ingredients representing 92.30% of the total oil were identified in the essential oil of O. basilicum L. The major ingredients were noted as methyl eugenol 52.97%, α-cubebene 10.82%, and spathenole 6.92%. The results were compared with other studies on the content of the O. basilicum L. plant. DPPH and β-carotene-Linoleic acid assays revealed considerable antioxidant activity of methyl eugenol-rich O. basilicum essential oil, which is lower than standard BHT, and higher than standard methyl eugenol. Multivariate curve resolution-alternative least squares (MCR-ALS) which is an iterative method was used for resolving the overlapped and embedded peaks. The results of this study show that chromatographic methods combined with MCR-ALS analysis techniques can be useful for a comprehensive, rapid, and specific analysis of complex natural products such as O. basilicum essential oils. In recent studies, the carcinogenic effects of methyl chavicol and methyl eugenol, the dominant active ingredients of O. basilicum L. were pointed.

The Ocimum basilicum essential oil (EO) was evaluated for its biological effect on M. domestica. Characterization of O. basilicum EO revealed the presence of methyl chavicol (70.93%), linalool (9.34%), epi-α-cadinol (3.69 %), methyl eugenol (2.48%), γ-cadinene (1.67%), 1,8-cineole (1.30%) and (E)-β-ocimene (1.11%). The basil EO and its constituents methyl chavicol and linalool caused the neuronal response in female adults of M. domestica. Adult female flies showed reduced preference to food source laced with basil EO and methyl chavicol. Substrate treated with EO and methyl chavicol at 0.25% caused an oviposition deterrence of over 80%. The ovicidal effect was high in O. basilicum EO (EC50 9.74mg/dm3) followed by methyl chavicol (EC50 10.67mg/dm3) and linalool (EC50 13.57mg/dm3. On contact toxicity, adults exposed to EO (LD50 10.01 μg/adult) were more susceptible than to methyl chavicol and linalool (LD50 13.62 μg/adult and LD50 43.12 μg/adult respectively). EO and its constituents methyl chavicol and linalool induced the detoxifying enzymes Carboxyl esterase (Car E) and Glutathione S – transferases (GST)

Due to the potential of phytochemicals as therapeutic agents, there is increased interest in plant compounds with this biological activity, such as the essential oils of medicinal and aromatic plan...

Chemical composition and bioactivities including bacterial and fungal resistance of the essential oils extracted from leaves of Piper betle L. (T) and Cleistocalyx operculatus L. (V) and aerial parts of Ageratum conyzoides L. (H) were investigated. The components presenting in the essential oils of the natural sources were analysized by a gas chromatography–mass spectrometry. Molecular docking simulation was utilised to support an antimicrobial mechanism of the essential oil compounds on Candida albicans fungus and Streptococcus pyogenes bacteria. This was based on the inhibition of the extracted compounds onto the microbial proteins, i.e. 4ESW and P0C0C7, respectively. There are 32 compounds identified in total in the three essential oils. The most effective inhibitors are the following: (i) chavicol acetate (T3), eugenol acetate (T11) and eugenol (T4) found in Piper betle L.; (ii) precocene II (H10) and precocene I (H6) found in Ageratum conyzoides L.; and (iii) caryophyllene oxide (V15) and cis-Lanceol (V19) found in Cleistocalyx operculatus L.. The overall antifungal and antibacterial capability of the investigated essential oils given indirect justification via their average inhabitability towards the two proteins accords with the order Piper betle L. Ageratum conyzoides L. Cleistocalyx operculatus L.. The results suggest these as promising natural sources for antimicrobial remedies.

The aim of this study was to investigate the influence of foliar application of Moringa oleifera leaf extracts (control, 2.5% and 5% aqueous MLE, 2.5% and 5% ethanolic MLE) and/or benzyladenine (control, 50, 100 and 200 ppm BA) on the growth, fruit and oil yield and its main components and chemical constituents of fennel (Foeniculum vulgare, Mill.) plants. The obtained results revealed that treated fennel plants with MLE and/or BA resulted in a significant increase in the vegetative growth, number of umbels/plant, fruit and oil yield per plant and feddan as well as total carbohydrates in fruits, chlorophyll a, b and carotenoids, nitrogen, phosphorus and potassium contents in leaves compared to untreated plants. Generally, the application of moringa leaf extracts was more effective than BA treatments. The individual treatment of aqueous MLE at 5% or BA at 100 ppm gave the best results of the previous mentioned characteristics followed by 5% ethanolic MLE or 50 ppm BA compared to the control and the rest of tested individual ones. The highest values of all studied parameters were obtained by using 5% aqueous or ethanolic MLE combined with 100 ppm BA. The increments were 91.1% and 85.3% in fruit yield/feddan, 52.5% and 46.3% in volatile oil percentage and 192.4% and 172.0% in oil yield/feddan, respectively over the control. The G.C. analysis of the volatile oil showed that the major component of volatile oil was methyl chavicol (estragole) with concentration range from 77.5% to 87.3%. The minor compounds were myrcene and limonene. The best treatment for decreasing the concentration of methyl chavicol (77.5%), which is undesirable component in fennel oil resulted from the combination of 5% aqueous MLE plus 100 ppm BA. Therefore, it could be recommended that spraying fennel plants with 5% aqueous MLE plus 100 ppm BA for obtaining higher vegetative growth, fruit and oil yield.

Increasing competition on water resources between the agriculture sector and other sectors requires new irrigation regimes to perform relevant levels of production in semi-arid regions. Field experiment was conducted during two successive seasons at the Experimental Farm of EL-Quassassin, Ismailia Governorate, Egypt. This experiment was prepared to assess the effects of different irrigation intervals, potassium phthalate and their combinations on the growth, number of umbels, fruit yield,water use efficiency, and volatile oil production of fennel plant during two successive winter seasons 2016/2017 and 2017/2018, respectively. Three irrigation treatments, main factor, as follow: I1(every three days, which is the common in this regionwith 1150 m3/ha), I2 (every five dayswith 766 m3/ha), and I3 (every seven dayswith 383 m3/ha), and the potassium phthalate as subsidiary factor (0, 400,500, and 600 ppm) were applied. The results showed that, the highest vegetative growth parameters were related to the potassium phthalate at the rate of 600 ppmand irrigation intervals 3 days.The highest values of fruit yield, as well asthe volatile oil production were significantly affected by the potassium phthalate and irrigation frequency in both seasons. Nevertheless, the concentrations of the macro and micro-nutrients in fruits revealed an increasing trend with increasing the irrigation intervals.In addition, the lower the amount of water use, the higher the water use efficiency.The results of GLC analysis of fennel volatile oil indicated that methyl chavicol as the main component varied between (63.02 and 80.82%). The treatment of potassium phthalate at 600 ppm with irrigation every 3days resulted in the lowest methyl chavicol percentage.Thus, the proper irrigation interval increases the plant water stress tolerance by increasing the water use efficiency and the nutrient concentrations of yield.

Southern pine beetles (Dendroctonus frontalis Zimmermann) and symbiotic fungi are associated with mass mortality in stands of Caribbean pine (Pinus caribaea Morelet). This study provides a 12.7-year assessment of semiochemical mediation between southern pine beetle and Caribbean pine in relation to concentrations of 4-allylanisole (estragole, methyl chavicol) and monoterpenes measured by gas chromatography–mass spectrometry in different seasons in premontane and coastal pine stands of Belize and Guatemala. Individual trees and stands with >2.5% (relative mass %) of 4-allylanisole in the xylem oleoresin exhibited significantly less beetle-induced mortality than those with P. caribaea may intensify in the future.

One of the diseases that can be transmitted by flies is diarrhea. Green betel leaf contains essential oils, chavicol, arecoline, phenol, and tannins which function as plant-based insecticides. This study aimed to determine the effectiveness of green betel leaf extract (Piper betel) as a plant-based insecticide on the number of mortality of house flies (Musca domestica). The research was an experimental study used After Only Design used the One Way Anova test with a 95% confidence level. The samples used were 360 ​​house flies. Each treatment of 30 house flies with 4 repetitions and used three concentrations of green betel leaf extract (25%, 50%, 75%). The study was conducted at the Chemistry and Microbiology Laboratory of Health Polytechnic Tanjungpinang, while the location of the fly collection was at the Tokojo Garbage Collection Station in Bintan Regency. The number of mortality of house flies at a concentration of 25% was 81 heads (67.5%), 50% concentrations were 93 heads (77.5%), and at a concentration of 75% were 103 heads (85.83%). There was an effect of green betel leaf extract on the mortality of house flies (p-value 0.0001

Synthetic insecticides applied to control Spodoptera frugiperda (Lepidoptera: Noctuidae) can have negative impacts on environment and human health. Botanical essential oils can be sources of organic molecules with biocontrol potential and advantages, such as minor impacts on the selection of resistant pest insects and low toxicity to humans. The aim of this study was to investigate the biocontrol action of essential oils from Brazilian species and methyl chavicol compounds on the development and metabolism of S. frugiperda. Essential oils of Eremanthus erythropappus (Asteraceae), Ocimum selloi, Hyptis suaveolens, and Hyptis marrubioides (Lamiaceae) were distilled by the steam distillation method and analyzed by gas chromatograph techniques. The essential oils were incorporated into an artificial diet (at 1, 2, and 4 mg mL-1) and offered to S. frugiperda caterpillars. Larvae of S. frugiperda at 48 h of age were fed an artificial diet containing the major constituent of O. selloi (methyl chavicol). The major compounds of the essential oils were methyl chavicol for O. selloi, α-bisabolol for E. erythropappus, bicyclogermacrene for H. suaveolens, and β-thujone for H. marrubioides. O. selloi caused 100% mortality in S. frugiperda larvae at a concentration of 1 mg mL-1 after 48 h. H. marrubioides essential oil caused 100% mortality in larvae at a concentration of 4 mg mL-1 after 48 h. O. selloi and H. marrubioides inhibited acetylcholinesterase (AchE) activity in 72.87% and 81.69% of larvae, respectively. O. selloi presented the highest toxicity to S. frugiperda and the lowest inhibition of AchE. Methyl chavicol was lethal to all larvae within 24 h at a concentration of 0.92 mg mL-1 of diet. Methyl chavicol showed the best insecticidal activity and potential to be used as a natural insecticide to control S. frugiperda.

In this study, antioxidant and antimicrobial activities of basil (Ocimum basilicum L.) essential oil (EO) in response to different Fe sources (Fe-arginine, Fe-glycine, and Fe-histidine nano-complexes and Fe-EDDHA) were examined. EO samples were predominantly constituted by the phenylpropanoid methyl chavicol (53–89.5%). Application of Fe nano-complexes significantly increased the occurrence and concentration of sesquiterpenes, while decreased the content of oxygenated monoterpenes. Antioxidant activity of basil EOs was evaluated using free radical 2,2-diphenyl-1-picrylhydrazyl, Nitric oxide, H2O2 and Thiobarbituric acid reactive substances scavenging assays, and in all assays the highest and the lowest activities were recorded in basils supplied with Fe-histidine nano-complex (1.02, 1.62, 2.21, 3.22 mg mL-1) and control (3.89, 4.89, 5.52, 6.79 mg mL-1), respectively. Fe-histidine nano-complex was the most effective treatment to inhibit fungal (C. albicans: 0.058 mg mL-1; A. niger: 0.066 mg mL-1), Gram-negative (E. coli: 0.181 mg mL-1; S. typhimurium: 0.163 mg mL-1) and Gram-positive (B. subtilis: 0.033 mg mL-1; S. aureus: 0.002 mg mL-1) growth. In conclusion, application of iron nano-complexes significantly altered biological and pharmacological characteristics of basil EOs. Our results are quite encouraging since EOs exhibited potent antioxidant effect and antimicrobial activities.

The Verbascum L. genus (Scrophulariaceae) is rich in phenols, flavonoids, and iridoid glycosides, which have been used extensively in traditional medicine. This study aimed to examine the association between genetics and metabolomics of V. songaricum populations (VSPs), collected from different geographical regions of Iran for further breeding and exploitation programs. Inter-simple sequence repeat (ISSR) analysis showed a significant difference among the twelve studied VSPs, which were classified into five main groups based on an unweighted pair-group method with arithmetic and principal coordinate analysis. Ninety-six bands were produced by fourteen ISSR primers, among which 92.7% of them were polymorphic at the species level. The essential oils were analyzed by means GC–FID and GC–MS and five main chemotypes, including docosane (I), methyl chavicol (II), methyl eugenol (III), β-damascenone (IV), and α-bisabolol (V) were characterized. HPLC–PDA–MS was further used to detect and to measure the phenolic compounds and harpagoside content in methanolic extract of VSPs. The main compounds identified in the VSPs extracts were rutin, quercetin, rosmarinic acid, salicylic acid, ferulic acid, p-coumaric acid, 2, 5-dihydroxybenzoic acid, 3, 4-dihydroxybenzoic acid, and harpagoside. Cluster analysis based on phytochemical data divided VSPs into nine groups. Subsequently, data were analyzed by multiple regression analysis to identify the correlation between genetic and metabolic diversity. The phytochemical data as the dependent variable showed significant association with bands obtained from molecular data. The high variation observed in essential oils, phenolics, and harpagoside among the VSPs establish a good potential to select the best genotype in breeding projects.

Prunus mume is a traditional ornamental plant, which owed a unique floral scent. However, the diversity of the floral scent in P. mume cultivars with different aroma types was not identified. In this study, the floral scent of eight P. mume cultivars was studied using headspace solid-phase microextraction (HS-SPME) and organic solvent extraction (OSE), combined with gas chromatography-mass spectrometry (GC-MS). In total, 66 headspace volatiles and 74 endogenous extracts were putatively identified, of which phenylpropanoids/benzenoids were the main volatile organic compounds categories. As a result of GC-MS analysis, benzyl acetate (1.55–61.26%), eugenol (0.87–6.03%), benzaldehyde (5.34–46.46%), benzyl alcohol (5.13–57.13%), chavicol (0–5.46%), and cinnamyl alcohol (0–6.49%) were considered to be the main components in most varieties. However, the volatilization rate of these main components was different. Based on the variable importance in projection (VIP) values in the orthogonal partial least-squares discriminate analysis (OPLS-DA), differential components of four aroma types were identified as biomarkers, and 10 volatile and 12 endogenous biomarkers were screened out, respectively. The odor activity value (OAV) revealed that several biomarkers, including (Z)-2-hexen-1-ol, pentyl acetate, (E)-cinnamaldehyde, methyl salicylate, cinnamyl alcohol, and benzoyl cyanide, contributed greatly to the strong-scented, fresh-scented, sweet-scented, and light-scented types of P. mume cultivars. This study provided a theoretical basis for the floral scent evaluation and breeding of P. mume cultivars.

Hedyosmum racemosum (Ruiz &amp, Pav.) G. is a native species of Ecuador used in traditional medicine for treatment of rheumatism, bronchitis, cold, cough, asthma, bone pain, and stomach pain. In this study, fresh H. racemosum leaves of male and female specimens were collected and subjected to hydrodistillation for the extraction of the essential oil. The chemical composition of male and female essential oil was determined by gas chromatography–gas chromatography equipped with a flame ionization detector and coupled to a mass spectrometer using a non-polar and a polar chromatographic column. The antibacterial activity was assayed against five Gram-positive and two Gram-negative bacteria, and two dermatophytes fungi. The scavenging radical properties of the essential oil were evaluated by DPPH and ABTS assays. The chemical analysis allowed us to identify forty-three compounds that represent more than 98% of the total composition. In the non-polar and polar column, α-phellandrene was the principal constituent in male (28.24 and 25.90%) and female (26.47 and 23.90%) essential oil. Other main compounds were methyl chavicol, germacrene D, methyl eugenol, and α-pinene. Female essential oil presented a strong activity against Klebsiella pneumoniae (ATCC 9997) with an minimum inhibitory concentration (MIC) of 500 μg/mL and a scavenging capacity SC50 of 800 µg/mL.

Ocimum species are herbaceous plants with great medicinal importance. Various tissues of the plants are being used in folk remedies for a variety of purposes. The pharmacologically active natural products present in essential oils in the Ocimum species belong to two major classes of natural compounds, viz. phenylpropanoids and terpenoids. In the present study, the essential oils from the inflorescence, leaf, and stem tissues of four major Ocimum species were hydro-distilled and analyzed. Gas chromatography–mass spectrometry profiling to unravel the phytomolecules and compositional quantification showed the occurrence of distinct tissue-based variability of phytomolecules. Phenylpropanoids such as eugenol and methyl chavicol were specifically found in the tissues of O. sanctum, O. gratissimum, and O. basilicum, respectively, whereas O. kilimandscharicum was distinct in possessing a terpenoid phytomolecule camphor predominantly in its tissues. The study also analyzed the uniqueness of the distribution of phytochemical constituents of essential oil in Ocimum species in tissue- and species-specific manner. Leaves were the major site of accumulation of essential oil, whereas inflorescence and stem also contained essential oil constituents albeit in low quantities.

Biological methods offer eco-friendly and cost-effective alternatives for the synthesis of silver nanoparticles (AgNPs). The present study highlights a green process where AgNPs were synthesized and optimized by using silver nitrate (AgNO3) and the aqueous extract of Piper betle (Pbet) leaf as the reducing and capping agent. The stable and optimized process for the synthesis of Pbet-AgNPs was exposure of reaction mixture into the sunlight for 40 min, pH 9.0, and 2 mM AgNO3 using 1:4 diluted Pbet leaf aqueous extract. The optimized Pbet-AgNPs were characterized by UV–visible spectroscopy, high-resolution field emission scanning electron microscopy (FE-SEM), X-ray diffractometry (XRD), and Fourier-transform infrared spectroscopy (FTIR). The prepared Pbet-AgNPs were spherical in shape with size in the range of 6–14 nm. These nanoparticles were stable for 6 months in aqueous solution at room temperature under dark conditions. The biogenic synthesized Pbet-AgNPs are found to have significant antifungal activity against plant pathogenic fungi, Alternaria brassicae and Fusarium solani. Synthesized Pbet-AgNPs potentially reduced the fungal growth in a dose-dependent manner. Microscopic observation of treated mycelium showed that Pbet-AgNPs could disrupt the mycelium cell wall and induce cellular permeability. Protein leakage assay supports these findings. Overall, this study revealed the efficacy of green synthesized AgNPs to control the plant fungal pathogens. Pbet leaves are a rich source of phenolic biomolecule(s). It was hypothesized that these biomolecule(s) mediated metal reduction reactions. In this context, the present work investigates the phytobiomolecule(s) of the aqueous extract of Pbet leaves using high-resolution liquid chromatography–mass spectroscopy (HR-LCMS) method. The analysis revealed that eugenol, chavicol, and hydroxychavicol were present in the Pbet aqueous extract.

Methyl chavicol (MC) is an oxygenated aromatic compound, suspected to be harmful to human health at high concentration. The present study focuses on the gas-phase oxidation mechanism of methyl chavicol initiated by OH radical by employing combined quantum chemical calculations and kinetic modelling. The initiation of the reaction is dominated by the abstraction of methyl chavicol hydrogen atom by OH radical and electrophilic addition of OH radical to the methyl chavicol. Energetically favourable reaction pathways and the stable products were identified by obtaining the reaction heats and potential energy surface. The rate constant for the favourable initial reactions has been calculated over the temperature range of 278–350 K using canonical variational transition state (CVT) theory with small curvature tunnelling (SCT) correction. The calculated thermodynamic and kinetic results reveal that the abstraction of hydrogen atom and addition of OH radical is more likely will occur at allyl group carbon atoms, C7, C8 and C9 of methyl chavicol to form radical intermediate, I4 and MC-OH adducts, I5 and I6. The subsequent secondary reactions for the initially formed intermediates were studied with O2, NO and HO2 radicals. The possible oxidation products identified are 4-methoxybenzaldehyde, (4-Methoxy-phenyl)-acetaldehyde and 4-methoxy toluene. The products identified in the present study are same as that identified experimentally and contribute to secondary organic aerosol loading in the atmosphere.

The aim of this study was to evaluate the concentration and chemical composition of the essential oil the leaves of basil cultivars and hybrids cultivated in different cropping seasons: dry season and rainy season. The variables evaluated were the content and composition of essential oils in the two seasons. The essential oil content ranged from 0.66% to 3.21% in the dry season and from 0.80% to 4.20% in the rainy season. The major compounds found among the genotypes were linalool, methyl chavicol, neral, geranial, eugenol, and methyl (E)-cinnamate, defining the formation of five groups in each season, classified in the following chemotypes: methyl chavicol (Group 1), citral (neral+geranial) (Group 2), methyl cinnamate (Group 3), linalool (Group 4), and intermediate linalool (Group 5). All the traits evaluated had heritability (h²) greater than 95% and high CVg/CVe ratio values. The cropping season affected the content and chemical compositions of basil essential oil.

In this study, the effect of operational conditions on the extraction of clove leaves using CO2 on eugenol yield and content was investigated. The conditions used in the supercritical extraction with CO2 included temperatures of 40, 50, and 60 °C and pressures of 150, 185 and 220 bar. The highest yield (1.08 wt%) and highest eugenol content were obtained at 40 °C and 220 bar. The main components identified in the clove extract were eugenol (29.73%), chavicol (13.31%), n-pentacosane (11.66%), hexacosanal (11.37%), and vitamin E (9.30%). The extracts were evaluated for their antioxidant capacities by the DPPH and FRAP methods, and quantification of the phenolic compounds was done by the Folin-Ciocalteu method. The best results among the conditions were obtained at the lowest pressure and temperature, 150 bar and 40 °C. The Sovova model satisfactorily described the extraction kinetics in all the studied conditions.

Sweet basil (Ocimum basilicum L.) is a widespread cultivated aromatic herb in the world. Information about both morphological and phytochemical characterization is very important prior to beginning of any breeding project. Therefore, the present study was conducted to investigate diversity of sweet basil accessions in cold tolerance, essential oil yield and essential oil compositions. The average of cardinal temperatures for seed germination were 7.9 (Tb) 21.7 (To) and 35.5 °C (Tc) and for germination rate were 7.9 (Tb) 25.7 (To) and 39.7 °C (Tc). Cumulative temperature response index (C-CTRI) was used to identify cold-tolerant accessions and based on C-CTRI, Pishva I and Zahedan II were the most cold-tolerant accessions. There was wide variation for herbage yield and contributing traits of sweet basil in two sites. The highest herbage yield was observed in Isfahan III and Birjand I at the normal and salinity conditions. Salinity decreased herbage yield, but increased essential oil content in all accessions. The highest essential oil content was recorded in Malayer and Birjand I at the normal and salinity conditions. Methyl chavicol (25.7–93.0%) was the main constituents of the essential oils among sweet basil accessions. We found four chemotypes based on the presence or absence of oil components: (1) high methyl chavicol (>80%) like Reunion basils, (2) medium methyl chavicol plus linalool like European basils, (3) high methyl chavicol (70–80%) along with neral, geranial, or linalool (all of them around 10%), and (4) medium methyl chavicol plus neral and geranial. Considering the yield and quality traits, Birjand I was significantly superior accession over studied accessions and thus, it has good potential for the cultivation and production of methyl chavicol rich essential oil.

Volatile profile, aroma-active compounds and odor activity values of the shade-dried aerial parts of basil (Ocimum basilicum) were investigated. Basil samples used under the study were provided from Iran and Turkey. Volatile compounds were isolated using a purge and trap extraction system and analyzed by gas chromatography olfactometry. A total of 50 volatile compounds of which 29 originated from Iranian and 32 were of Turkish origin were determined. Terpenes were present at the overwhelmingly highest levels, followed by alcohols and aldehydes. Of the terpenes, methyl chavicol was the main compound of both samples. The aroma-active compounds of basils were investigated by using aroma extract dilution analysis (AEDA) for the first time. The application of AEDA revealed 18 aroma-active compounds, including terpenes (10), aldehydes (3), ketone (1), phenol (1), alcohol (1), and unknown compounds (2) were detected. Linalool and methyl chavicol had the greatest flavour dilution (FD) factors in both samples, amounting to 2048 and 1024, respectively. © 2018 Elsevier B.V.

Medicinal and aromatic crops are economically important because they are sources for secondary metabolites such as essential oils (EOs) and polyphenolic compounds. High biomass yields are obtained by conventional chemical fertilizers, whereas the production of EOs is more influenced by elicitors that act on secondary metabolic pathways. The objective of the field trials was to evaluate the effects of biologic and conventional fertilizers (biosolids: 40 and 20 t ha−1, organic: 600 kg ha−1, microorganisms (arbuscular mycorrhizal fungi, AMF): 60 kg ha−1, chemical NPK 20-20-20: 300 kg ha−1) on plant growth, EO chemical profile and yield, and physiology of sweet basil (Ocimum basilicum L.). The two sweet basil cultivars (varieties) used were the green-leafed ‘Aromat de Buzau’ and the purple-leafed ‘Violet de Buzau’. The greatest increases in fresh yields compared with unfertilized plants, 116% and 68% increases for the ‘Aromat de Buzau’ and ‘Violet de Buzau, respectively, were obtained from the conventionally (chemical) fertilized plants. The 40 t ha−1 biosolids treatment increased the EO content of the ‘Aromat de Buzau’ by 30%, while the AMF and organic treatments increased the EO content of the ‘Violet de Buzau’ by 21%. The major constituents of ‘Aromat de Buzau’, methyl chavicol and β-linalool, were increased by 4 and 17% with the AMF and organic treatments, respectively. Eucalyptol and δ-guaiene concentrations in the EO were higher in the 40 t ha−1 biosolids treatment, while τ-cadinol and γ-cadinene were higher in the 20 t ha−1 biosolids treatment. For ‘Violet de Buzau’, the AMF treatment led to an increase of β-linalool, limonene, and (+)-camphor, and decreased the concentration of methyl chavicol. The organic treatment increased the concentrations of limonene, (+)-camphor, terpinene-4-ol, and β-caryophyllene, and decreased the concentration of methyl chavicol. The highest concentration of methyl chavicol was observed in the chemical fertilizer treatment. The 20 and 40 t ha−1 biosolids treatments led to highest yields of eucalyptol, (+)-camphor, terpinene-4-ol, β-caryophyllene, germacrene D, and τ-cadinol. The results demonstrated that conventional fertilizers can increase fresh yield while biological fertilizers positively alter the EO composition, leading to increased crop quality.

This study demonstrates liquid crystal (LC) alignment behaviors on the surface of phytochemical-based and renewable chavicol-modified polystyrene (PCHA#, # = 20, 40, 60, 80, and 100, where # represent the molar content of chavicol moiety in the side group) via polymer modification reactions. Generally, a LC cell fabricated with a polymer film containing a high molar content of the chavicol side group exhibited a vertical LC alignment property. There is a correlation between the vertical alignment of LC molecules and the polar surface energy value of the polymer films. Therefore, vertical LC alignment was observed when the polar surface energy values of these polymer films were smaller than about 1.3 mJ/m2, induced by the nonpolar chavicol moiety having long and bulky carbon groups. Aligning stability under harsh conditions such as ultraviolet (UV) irradiation of about 5 J/cm2 was observed in the LC cells fabricated from PCHA100 film. Therefore, it was found that the plant-based chavicol-substituted polymer system can produce an eco-friendly and sustainable LC alignment layer for next-generation applications.

The continuous use of synthetic anthelmintics against gastrointestinal nematodes (GINs) has resulted in the increased resistance, which is why alternative methods are being sought, such as the use of natural products. Plant essential oils (EOs) have been considered as potential products for the control of GINs. However, the chemical composition and, consequently, the biological activity of EOs vary in different plant cultivars. The aim of this study was to evaluate the anthelmintic activity of EOs from cultivars ofOcimum basilicumL. and that of their major constituents againstHaemonchus contortus.The EOs from 16 cultivars as well the pure compound linalool, methyl chavicol, citral and eugenol were used in the assessment of the inhibition ofH. contortusegg hatch. In addition, the composition of three cultivars was simulated using a combination of the two major compounds from each. The EOs from different cultivars showed mean Inhibition Concentration (IC50) varying from 0.56 to 2.22 mg/mL. The cultivar with the highest egg-hatch inhibition, Napoletano, is constituted mainly of linalool and methyl chavicol. Among the individual compounds tested, citral was the most effective (IC500.30 mg/mL). The best combination of compounds was obtained with 11% eugenol plus 64% linalool (IC500.44 mg/mL), simulating the Italian Large Leaf (Richters) cultivar. We conclude that different cultivars ofO. basilicumshow different anthelmintic potential, with cultivars containing linalool and methyl chavicol being the most promising; and that citral or methyl chavicol isolated should also be considered for the development of new anthelmintic formulations.

Malvaviscus arboreus Cav., commonly known as Sleeping Hibiscus, is a plant species that belongs to the family Malvaceae with ornamental, culinary, and ethnomedical importance. This medicinal herb was reported to exhibit noteworthy antioxidant, cytotoxic, hepatoprotective, and anti-infective activities attributed to the presence of a variety of phytochemicals. In this work, the volatile compositions of the leaves and flowers of M. arboreus were studied and compared for the first time using the headspace gas chromatography-mass spectrometry (GC–MS) technique. Overall, 39 components were identified, comprising 36 from the leaves and 11 from the flowers, with an evident greater contribution of oxygenated compounds (89.54% in leaves and 89.35% in flowers) to their total volatiles. Phenolic ethers (41.64%) and ketones (21.57%) were the major chemical groups emitted by the flowers, while ketones (27.40%) and carboxylic acids (18.16%) dominated the volatile blends of the leaves. Anethole (32.32%), methyl isobutenyl ketone (19.18%), and methyl chavicol (9.32%) were the most abundant floral volatiles, whereas acetic acid (18.16%) was the major constituent given off by the leaves, followed by 2-cyclohexenone (9.60%) and anethole (7.39%). Additionally, from a biosynthetic point of view, the floral volatiles of M. arboreus showed the prevalence of phenylpropanoids/benzenoids (41.64%); however, fatty acid derivatives (54.30%) predominated among those produced by the leaves. The obtained results revealed noteworthy qualitative and quantitative variations in M. arboreus leaves and flowers' headspace volatiles that would help complement our phytochemical knowledge on this limitedly studied plant. Resumen. Malvaviscus arboreus Cav., comúnmente conocida como “Sleeping Hibiscus”, es una especie vegetal que pertenece a la familia Malvaceae con importancia ornamental, culinaria y etnomédica. Se ha reportado que esta hierba medicinal exhibe actividades antioxidantes, citotóxicas, hepatoprotectoras y antiinfecciosas notables que se atribuyen a la presencia de una variedad de fitoquímicos. En este trabajo se estudiaron las composiciones volátiles de las hojas y flores de M. arboreus y fueron comparadas utilizando la técnica de cromatografía de gases-espectrometría de masas (GC-MS). En total, se identificaron 39 componentes comprendiendo 36 de las hojas y 11 de las flores, con un evidente mayor aporte de compuestos oxigenados (89,54% en hojas y 89,35% en flores). Los éteres fenólicos (41,64%) y cetonas (21,57%) fueron los principales grupos químicos emitidos por las flores, mientras que las cetonas (27,40%) y los ácidos carboxílicos (18,16%) dominaron las mezclas volátiles de las hojas. Anetol (32,32%), metil isobutenil cetona (19,18%) y metil chavicol (9,32%) fueron los volátiles florales más abundantes, mientras que el ácido acético (18,16%) fue el principal componente desprendido por las hojas, seguido de la 2-ciclohexenona. (9,60%) y el anetol (7,39%). Adicionalmente, desde el punto de vista biosintético, los volátiles florales de M. arboreus mostraron la prevalencia de fenil propanoides/benzenoides (41,64%); sin embargo, los derivados de ácidos grasos (54,30%) predominaron entre los producidos por las hojas. Los resultados obtenidos revelaron variaciones cualitativas y cuantitativas notables en los volátiles de las hojas y flores de M. arboreus que ayudarán a complementar nuestro conocimiento fitoquímico en esta planta estudiada hasta ahora de forma limitada.

Ethnopharmacological relevance The population uses the aqueous extract as tea from leaves of Ocimum selloi Benth. (alfavaca) for pain and inflammation issues. This study is motivated by a lack of data about inflammation properties of O. selloi. Aim of the study This study investigated the chemical composition and anti-inflammatory activity, in mice models, of the aqueous extract (OSAE) and essential oil (OSEO) obtained from leaves of O. selloi. Materials and methods The antioxidant activity and total phenolic content were evaluated for samples, although chemical composition was obtained by U-HPLC-DAD-ESI-MS for OSAE and GC-MS for OSEO. OSAE and OSEO were tested orally at doses of 30, 100 and 300 mg/kg at the carrageenan-induced pleurisy and paw edema, also mechanical hyperalgesia, in mice. Results Four glycosylated flavonoids and one organic acid were identified in OSAE, and nine substances in OSEO, the two majoritarian are E-anethole and methyl chavicol. Oral treatments with OSAE and OSEO significantly inhibited the carrageenan-induced pleurisy in female Swiss mice, besides OSAE and OSEO significantly prevented paw edema (after 1, 2, and 4 h), mechanical hyperalgesia (after 3 and 4 h), and cold hyperalgesia 3 h after carrageenan model in male Swiss mice. The dose of 300 mg/kg of OSEO reduced cold hyperalgesia 4 h after carrageenan. Conclusion The results evidenced the anti-inflammatory, anti-edematogenic, anti-hyperalgesic, and anti-nociceptive potentials of both materials obtained from leaves of O. selloi, mainly OSAE, supporting the popular use of this species.

The study explores the antioxidant activity, volatile chemical profile and antifungal potential of Pimenta dioica leaf essential oil (EO) against toxin producing Aspergillus flavus. GC–MS analysis of EO revealed the presence of 41 compounds with eugenol (54%), as the major compound followed by myrcene (16.0%) and chavicol (12.5%). It exhibited the strong antioxidant activity with IC(50) value of 19.40 µg/ml and polyphenolic content of 526.9 mg g(−1) gallic acid equivalent. The aflatoxin producing IISRaf1strain from nutmeg (Myristica fragrans) was identified by 18S rRNA sequencing as Aspergillus flavus (MH345939). MIC of P. dioica leaf EO against A. flavus was found to be at 0.04%. The changes in hyphae growth and architecture after treatment with EO were observed under light microscopy. Antifungal compounds eugenol which got separated at the particular spot caused the clear zone at the TLC plate by agar overlay bioassay. The mode of action of antifungal activity of EO was recorded in terms of its effect on ergosterol content of plasma membrane and malate dehydrogenases activity (MDH) of A. flavus. Thus P. dioica leaf EO might be viable alternative as plant based preservative in perspective on its antioxidant, antifungal activity and efficacy in food system. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (10.1007/s13197-020-04756-0) contains supplementary material, which is available to authorized users.

The study evaluated the chemical profile, antimicrobial activity and toxicity of essential oils (EOs) of C. citratus, O. basilicum and A. rosaeodora. The EOs were extracted by hydrodistillation, the chemical profile was determined using the physicochemical parameters and the chemical composition was obtained by gas chromatography coupled to mass spectrometry (GC-MS). The toxicity assay followed the Artemia salina Leach bioassay. To perform the antimicrobial activity, the Disc Diffusion technique and the Mueller Hinton Broth Dilution (MH) technique were used. The physicochemical parameters of the EOs showed satisfactory results. The major chemical composition of the EO of A. rosaeodora presented linalool (93.60%), the EO of C. citratus exhibited geranial (43.96%) and EO of O. basilicum found methyl chavicol. All EOs in this study had LC50 between 582 mg L-1 and 282 mg L-1. The antimicrobial activity of EO C. citratus demonstrated inhibition halos for S. aureus of 25 mm and 25 mm for E. coli, EO of O. basilicum exhibited inhibition halo of 18 mm for E.coli and 20 mm for S. aureus and EO of A. rosaeodora presented 11 mm for E. coli and 15 for S. aureus. As the values of MIC and MBC found, the EO of O. basilicum presented a more effective inhibitory action against S. aureus. It was concluded that the observed biological potentials encourage the application potentials in the efficiency of the control of pathogenic microorganisms.

This study was to examine the in vitro antioxidant activities of forty-five commonly used essential oils and their major components. The oils and major components were subjected to screening for their possible antioxidant activity by measuring the ABTS(superscript +‧) radical scavenging ability, reducing power and metal chelating activity. The ABTS(superscript +‧) radical scavenging ability and reducing power of cinnamon leaf and clove bud essential oils are the best two among these essential oils. At the concentration of 1 mg/mL, cinnamon leaf (96.45±0.01%) and clove bud (96.33±0.01%) essential oils showed the strongest ABTS(superscript +‧) radical scavenging ability. The EC50 values of cinnamon leaf and clove bud essential oils are 12μg/mL and 10μg/mL, respectively. At the concentration of 10 mg/mL, cinnamon leaf and clove bud essential oils showed reducing power of 119.42±0.68% and 112.92±0.87% relative to butylated hydroxyanisole (BHA), respectively. Eugenol is the main component of cinnamon leaf and clove bud essential oils that contributes significantly to their ABTS(superscript +‧) radical scavenging activity and reducing power. In the metal chelating activity test system, basil essential oil was determined to be 57.48±0.25% and its EC50 value is 984μg/mL. Methyl chavicol is the major component of the basil essential oil that attributes greatly to its metal chelating activity. The higher phenolic content may explain the higher ABTS(superscript +‧) radical scavenging and reducing power activity of the forty-five kinds of commonly used essential oils. High electron density of the oxygen atom and low steric hindrance of the plane molecule of the methyl chavicol are the two possibilities that account for its higher metal chelating ability.

Environmental stresses might alter the activity of antioxidant defense system and both quantity and quality of the essential oil constituents in aromatic plants. In the current study, a greenhouse experiment was designed to assess the influence of cold stress on total phenolic (TPC) and flavonoid contents (TFC), DPPH radical scavenging, antioxidant and phenylalanine ammonia-lyase (PAL) enzymes activity and content of phenylpropanoid compounds in Ocimum basilicum L. The genes expression levels of chavicol O-methyl transferase (CVOMT), cinnamate 4-hydroxylase (C4H), eugenol synthase 1 (EGS1) and eugenol O-methyl transferase (EOMT) were also investigated. Results revealed the highest TPC, TFC and DPPH at 4 °C for 12 h. Positive significant correlation was observed between TFC and DPPH, as well as TPC and PAL enzyme activity. The highest activity of superoxide dismutase and guaiacol peroxidase was recorded in 4 °C for 48 h, while this treatment caused the highest reduction in the activities of ascorbate peroxidase and catalase. In plants exposed to 10 °C for 48 h, the contents of methyleugenol and methylchavicol was positively associated with the expression levels of EGS1 and EOMT. A positive correlation was also found between C4H expression and eugenol, methyleugenol and methylchavicol contents under 4 °C for 12 h.

Currently essential oils are increasingly used as natural insecticides because of the adverse effects on human health and environmental pollution of synthetic insecticides. The aim of this study is to perform the encapsulation of Ocimum basilicum L. essential oils by freeze-drying technique using binary mixtures maltodextrins and acacia gum to investigate their insecticidal activity against three insect pests of stored-products Rhyzopertha dominica, Sitophilus oryzae and Tribolium castaneum by direct contact and ingestion toxicity effects. Essential oils were obtained by solvent-free microwave extraction (SFME) and conventional hydro-distillation (HD) methods. Chemical composition of essential oils analysed by GC-MS indicated that the major components were linalool (43.5% for SFME and 48.4% for HD) followed by methyl chavicol (13.3% for SFME and 14.3% for HD) and 1,8-cineole (6.8% for SFME and 7.3% for HD). The toxic effects results, confirm that O. basilicum essential oils capsules were highly effective against R. dominica than S. oryzae, except for T. castaneum which was insensitive. The toxicity against adults of R. dominica varied between (LD50 = 0.20 g/kg for SFME-EEO, LD50 = 0.25 g/kg for HD-EEO) and (LD50 = 0.32 g/kg for SFME-EEO, LD50 = 0.37 g/kg for HD-EEO) by direct contact and ingestion effect, respectively. These results lead us to consider such essential oils capsules as providing a richer source of natural insecticide agents for food preservation.

As one of the last places where coffee grows spontaneously, the Harenna forest (Ethiopia) is the origin of the coffee analysed in this study. The analysis of the volatile emission of each processing phase evaluates the chemical fingerprint of the reactions taking place at each stage, leading to the final aroma. The green beans mainly emit non-terpene esters and alkanes. Once the roasting begins, monoterpenes are the main class until 160 °C: at this point, 2,6-dimethylpyrazine prevails in the headspaces, as main product of the Maillard reactions. This compound, with its sweet and nut-like aroma, is also detected in the brewed coffee. The shed silverskins are rich in methyl chavicol and retain the monoterpenes on the beans: as these compounds are important aroma contributors, the removal of the silverskins prior to roasting seems non-advisable. The grinding of the samples breaks the matrices and leads to drastic changes in the volatile emissions.

In order to evaluate the quali-quantitative traits of fennel (Foeniculum vulgare L.) when intercropped with common bean (Phaseolus vulgaris L.) in different cropping patterns and under PGPR application, a two-years field experiment (2015 and 2016) was arranged as factorial design based on randomized complete blocks (RCBD) with three replications. The first factor consisted of six cropping patterns including sole cropping of fennel, sole cropping of common bean, and different intercropping ratios of fennel to common bean (1:1, 2:2, 3:2, 4:2), whereas the second factor included the application and non-application of PGPR. The results showed that the highest seed yields of common bean (2474.83 kg ha−1) and fennel (2730.08 kg ha−1) were produced with sole cropping combined under PGPR application. The fennel essential oil (EO) and seed oil (fixed oil) content in all intercropping patterns were higher than those in sole cropping. Furthermore, under PGPR application, the seed yield, EO content, EO yield, fixed oil content and oil yield of fennel increased by 20.9, 16.4, 39.3, 10.3 and 33.3 %, respectively, compared with control. Based on the chemical analysis of fennel EO, the main constituents were (E)-anethole (73.71–81.10%), fenchone (3.44–6.18%), limonene (3.49–5.82%) and methyl chavicol (4.06–7.22%). The major fatty acids in fennel fixed oil were oleic (77.17–82.90%), linoleic (6.50–8.97%) and palmitic acids (3.25–6.80%). The highest content of unsaturated fatty acids (oleic and linoleic acids) and (E)-anethole were obtained with intercropping ratios (fennel to common bean) of 2:2 and 3:2 under PGPR application, respectively. Furthermore, the highest land equivalent ratio (1.32) was obtained with intercropping ratio of 3:2 under PGPR application. Our findings showed that the intercropping ratio of 2:2 and 3:2 upon PGPR biofertilization may be suggested to farmers instead of sole cropping for enhancing the fennel EO and fixed oil quali-quantitative composition.

Chemical analysis of the bark from four Hyrcanian forest species, Pterocarya fraxinifolia, Alnus subcordata, Gleditsia caspica and Parrotia persica were performed, and their total phenol contents, and antioxidant and chelating activities were evaluated. The greatest total phenol content (TPhC), 54.3% in dry extract, was detected in P. fraxinifolia bark and the lowest one in G. caspica bark with 4.5%. The 50% inhibitory concentrations (IC50) in the radical-scavenging assay against DPPH radicals in bark acetone extracts of P. fraxinifolia, A. subcordata, G. caspica and P. persica were 0.17, 0.21, 13.35, 0.19 mg ml−1, respectively. In the metal-chelating activity system, G. caspica extract demonstrated significant activity. Pterocarya fraxinifolia, A. subcordata and P. persica bark acetone extracts revealed a high potential for inhibition of DPPH radicals due to high amounts of phenolics. Superior health benefits can be expected from the compounds syringol, 4-vinylguaiacol, tyrosol, chavicol, resorcinol, hydroquinone, vanillin, rheosmin and acetophenone. Gleditsia caspica was found to have significant chelating activity due to isoeugenol.