Methyl Eugenol Research Articles

The chemotypes of Ethiopian Ocimum basilicum L. (sweet basil) germplasms

Sweet basil (Ocimum basilicum L.) exhibits significant chemical variability. This study characterized the chemical composition of 49 accessions of O. basilicum collected from different parts of Ethiopia using GC–MS. Results of this analysis revealed the presence of 46 compounds. Four compounds (eucalyptol, linalool, estragole, and eugenol) were found in all accessions, and seven compounds were found in large quantities of more than 10 %; methyl cinnamate (41.9 %), geraniol (27.9 %), linalool (25.41 %), eugenol (23.08 %), β-bisabolene (23.03 %), eucalyptol (17 %) and estragole (16.6 %). Cluster analysis grouped the 49 accessions into four chemotypes. Chemotype A consisting of eugenol/ estragole/ eucalyptol/ β-bisabolene), chemotype B (eucalyptol/estragole), chemotype C (linalool/geraniol) and chemotype D (methyl cinnamate/linalool). The results of this study indicated that the compounds found in Ethiopian O. basilicum accessions are highly diverse. Overall, the results of this study will provide scientific basis for future breeding programs of this crop.

Effects of Harvest Timing on Phytochemical Composition in Lamiaceae Plants under an Environment-Controlled System.

The Lamiaceae family is widely recognized for its production of essential oils and phenolic compounds that have promising value as pharmaceutical materials. However, the impact of environmental conditions and different harvest stages on the phytochemical composition of Lamiaceae plants remains poorly understood. This study aimed to investigate the effects of harvest time on the phytochemical composition, including rosmarinic acid (RA) and volatile organic compounds (VOCs), of four Lamiaceae plants-Korean mint (AR), lemon balm (MO), opal basil (OBP), and sage (SO)-and was conducted under an environment-controlled system. Although all four plants had RA as the dominant compound, its distribution varied by species. The flowered plants, including AR and OBP, exhibited a rapid increase of RA during the transition from the vegetative stage to the reproductive stage. In contrast, non-flowered groups, including MO and SO, showed a steady increase in the content of total phenolics and RA. The main components of VOCs also differed depending on the plant, with characteristic fragrance compounds identified for each one (AR: estragole; MO: (Z)-neral and geranial; OBP: methyl eugenol, eugenol, and linalool; and SO: (Z)-thujone, camphor, and humulene). The total VOCs content was highest on the 60th day after transplanting regardless of the species, while the trends of total phenolics, RA content, and antioxidant activities were different depending on whether plant species flowered during the cultivation cycle. There was a steady increase in species that had not flowered, and the highest content and activity of the flowering period were confirmed in the flowering plant species.

Urinary Excretion of Mercapturic Acids of the Rodent Carcinogen Methyleugenol after a Single Meal of Basil Pesto: A Controlled Exposure Study in Humans.

Methyleugenol (ME), found in numerous plants and spices, is a rodent carcinogen and is classified as "possibly carcinogenic to humans". The hypothesis of a carcinogenic risk for humans is supported by the observation of ME-derived DNA adducts in almost all human liver and lung samples examined. Therefore, a risk assessment of ME is needed. Unfortunately, biomarkers of exposure for epidemiological studies are not yet available. We hereby present the first detection of N-acetyl-l-cysteine conjugates (mercapturic acids) of ME in human urine samples after consumption of a popular ME-containing meal, pasta with basil pesto. We synthesized mercapturic acid conjugates of ME, identified the major product as N-acetyl-S-[3'-(3,4-dimethoxyphenyl)allyl]-l-cysteine (E-3'-MEMA), and developed methods for its extraction and LC-MS/MS quantification in human urine. For conducting an exposure study in humans, a basil cultivar with a suitable ME content was grown for the preparation of basil pesto. A defined meal containing 100 g of basil pesto, corresponding to 1.7 mg ME, was served to 12 participants, who collected the complete urine at defined time intervals for 48 h. Using d6-E-3'-MEMA as an internal standard for LC-MS/MS quantification, we were able to detect E-3'-MEMA in urine samples of all participants collected after the ME-containing meal. Excretion was maximal between 2 and 6 h after the meal and was completed within about 12 h (concentrations below the limit of detection). Excreted amounts were only between 1 and 85 ppm of the ME intake, indicating that the ultimate genotoxicant, 1'-sulfooxy-ME, is formed to a subordinate extent or is not efficiently detoxified by glutathione conjugation and subsequent conversion to mercapturic acids. Both explanations may apply cumulatively, with the ubiquitous detection of ME DNA adducts in human lung and liver specimens arguing against an extremely low formation of 1'-sulfooxy-ME. Taken together, we hereby present the first noninvasive human biomarker reflecting an internal exposure toward reactive ME species.

Population dynamics of fruit flies and correlation matrix with weather and host variables in mango (Mangifera indica) orchards

The present study was carried out in the Mango orchards at Indian Agricultural Research Institute, New Delhi during 2020–2021 and 2021–2022 and aimed at analysing the population dynamics of fruit fly (Bactrocera dorsalis) species after putting the requisite number of methyl eugenol traps (@6 per acre). Weekly monitoring of fruit fly populations was performed and correlated with various weather parameters. Among the fruit fly species, the oriental fruit fly was found to be the most prevalent and abundant, followed by B. zonata, B. correcta, and B. cucurbitae. Fruit fly populations peaked in mango plantations between June and July, coinciding with the ripening time and the occurrence of humid conditions and rainfall. Multiple factors, including weather conditions, the presence of preferred host plants, and alternative hosts, fruits characteristics were found to influence the dynamics of fruit fly populations. The seasonal trap captures of male fruit flies showed a moderately significant negative correlation (-0.612*) with maximum but significant positive correlation with the minimum temperature (0.701**). However, a positive correlation was observed between relative humidity (r = 0.924**) and rainfall (r = 0.721**) with the fluctuations of fruit fly populations across all the monitored orchard sites.

Essential oil, flavonoids and anthocyanins profiling of some Iranian damask rose (Rosa damascena Mill.) genotypes

Increasing production efficiency is necessary for the industrialization of plant cultivation which includes the type and content of metabolites in medicinal and aromatic plants. In the present study, the metabolic diversity of twenty-four Iranian Rosa damascena genotypes (G1-G24) was studied. The essential oils isolated from fresh flowers and methanolic extracts from dried petal samples were analyzed by chromatographic techniques. In total, forty-three chemical compounds were identified in the essential oil samples. Geraniol (0.2–45.8%), β-citronellol (1.9–22.3%), and nerol (1.4–15.2%) were the major compounds identified in the studied oils especially in G5, G7, and G22, respectively. Twelve flavonoids and four anthocyanins were identified in the extracts. The highest flavonoid content (48.9 mg/g DW) was recorded in G2. Kaempferol 3-O-glucoside (6.1–12.9 mg/g DW), quercetin 3-O-glucoside (0.9–11.4 mg/g DW), and quercetin 7-(6''-galloylglucoside) (0.3–9.2 mg/g DW) were identified as the main flavonoids in the studied genotypes. The highest content of anthocyanin (37.0 mg/g DW) was observed in G1. Cyanidin 3,5-O-diglucoside was found only in G17 and G18, while cyanidin 3-O-sambubioside was unique in G1. β-Citronellol and methyl eugenol had positive (β > 0.5) and negative (β > 0.6) correlations with flavonoids kaempferol 3-O-galactoside 7-O-rhamnoside (K3g7r) and Q3g in the studied samples, respectively; so, this finding can be interestingly used as a phytochemical marker to select the damask rose genotypes producing high-quality essential oil. In conclusion, G21, G2, and G1 can be distinguished and used as adequate genotypes for further commercial cultivation to obtain the essential oil, flavonoids, and anthocyanins, respectively.

Methyleugenol Has an Antidepressant Effect in a Neuroendocrine Model: In Silico and In Vivo Evidence.

Major depressive disorder is a severe mood disorder characterized by different emotions and feelings. This study investigated the antidepressant activity of the phenylpropanoid methyleugenol (ME) in adult female mice exposed to a stress model induced by dexamethasone. The animals were randomly divided into groups containing eight animals and were pre-administered with dexamethasone (64 μg/kg subcutaneously). After 165 and 180 min, they were treated with ME (25, 50 and 100 mg/kg intraperitoneally) or imipramine (10 mg/kg intraperitoneally) after 45 min and 30 min, respectively; they were then submitted to tests which were filmed. The videos were analyzed blindly. In the tail suspension test, ME (50 mg/kg) increased latency and reduced immobility time. In the splash test, ME (50 mg/kg) decreased grooming latency and increased grooming time. In the open field, there was no statistical difference for the ME groups regarding the number of crosses, and ME (50 mg/kg) increased the number of rearing and time spent in the center. Regarding in silico studies, ME interacted with dopaminergic D1 and α1 adrenergic pathway receptors and with tryptophan hydroxylase inhibitor. In the in vivo evaluation of the pathways of action, the antidepressant potential of ME (50 mg/kg) was reversed by SCH23390 (4 mg/kg intraperitoneally) dopaminergic D1 receptor, Prazosin (1 mg/kg intraperitoneally) α1 adrenergic receptor, and PCPA (4 mg/kg intraperitoneally) tryptophan hydroxylase inhibitor. Our findings indicate that ME did not alter with the locomotor activity of the animals and shows antidepressant activity in female mice with the participation of the D1, α1 and serotonergic systems.

Field Evaluation of Slow-Release Wax Formulations: A Novel Approach for Managing Bactrocera zonata (Saunders) (Diptera: Tephritidae)

Chemical management of the peach fly, Bactrocera zonata has been compromised due to adverse effects of pesticide residues that not only contaminate environment but also affect non-target organisms including beneficial insects, birds, aquatic life, and soil microorganisms. They can be impacted through direct exposure or by consuming contaminated prey or plants. The present study was designed keeping in view this increasing demand of the consumers to get pesticide residue free fruit and vegetable produce because it reflects the growing consumer concern for food safety and environmental sustainability, motivating the need for alternative pest management strategies. The field experiment was conducted to determine the best slow-release formulation prepared by mixing the following five different types of waxes, including Candelilla wax (CanW), Paraffin wax (PW), Carnauba wax (CarW), Lanolin wax (LW) and Bees wax (BW) with methyl eugenol (ME) (to attract male B. zonata). The selection of the five different types of waxes was likely based on their biodegradability, availability, and potential for slow-release properties. The result revealed that formulations containing SRF-7[LW], SRF-9[CanW], SRF-8[BW], SRF-9[CarW] and SRF-9[PW] exhibited the maximum capture of 42.10 ± 8.14, 43.30 ± 1.76, 34.30 ± 2.96, 35.30 ± 3.18 and 22.70 ± 3.18 male B. zonata per trap per day, respectively. These effective formulations were further evaluated in experiment in which the comparative trapping efficiency of each wax formulation was assessed. The results demonstrated that formulation containing SRF-9[CanW] was expressed maximum capture 13.77 ± 1.26 male B. zonata per trap per day. These formulations were further evaluated in another experiment in which the trapping efficiency was assessed by four different application methods (simple bottle trap, simple bottle trap with water, yellow sticky trap and jute piece with sticky material). The results demonstrated that formulation containing SRF-9[CarW] applied by yellow sticky trap (YST) trapped 61.74 + 7.69 male B. zonata per trap per day and proved more effective. This formulation can be recommended for trapping and management of male population of B. zonata in fruit orchards. This study can influence eco-friendly B. zonata pest control policies, reducing chemical pesticide usage and promoting agricultural sustainability. Future research should study the long-term impact of slow-release formulations on agricultural sustainability, including pest control, crop yield, and agroecosystem health.

Valorization of tuberose flower waste through development of therapeutic products using supercritical carbon dioxide extraction and microencapsulation technologies.

Tuberose flowers (Calcutta Single variety) valued as ornamentals globally, have short shelf-lives of 8 days at 4 ± 1°C and are therefore discarded post senescence. Previous investigations from our laboratory have established that a combination treatment using GRAS preservatives [(sucrose (4%) and CaCl2 (0.02%)]-cum-gamma-irradiation (0.02kGy) could extend its shelf-life to 24 days, when stored at 4 ± 1°C with concomitant enhancement in the content of its bioactive principle, viz. methyl eugenol. Supercritical carbon dioxide (SC-CO2) extract of the tuberose flower wastes post combination treatment therefore had a higher methyl eugenol content (4.11 ± 0.05µg/g), vis-à-vis its non-treated counterpart (2.03 ± 0.03µg/g), and thus significantly higher antioxidant and antimicrobial potencies (MIC values of 1.83 ± 0.02mg/ml and 1.98 ± 0.03mg/ml against S. aureus ATCC 25923 strain and MDR strain, respectively). The microencapsulated powder of the extract (MEp) obtained by spray drying was applied for healing of epidermal wounds created on New Zealand white rabbits, post skin irritancy test (wherein no clinical sign of toxicity, redness or swelling was observed). When MEp was applied, accelerated healing occurred which commenced on day 2 and was completed by day 6 vis-à-vis that of the control powder set (without extract) which showed no signs of wound healing. Therefore, the sensorially compromised-senesced tuberose flowers, a rich source of methyl eugenol, has been successfully valorized through utilization of the same in developing a novel topical antibiotic powder against potent skin pathogens.

A rapid method for the determination of alkenylbenzenes in spices by gas chromatography - high resolution mass spectrometry (GC-HRMS)

Alkenylbenzene is a group of natural toxins that can cause genetic damage and cancer in rodents. These toxins are found in high amounts in common spices such as pepper, basil, cinnamon, dill, and others. This study aimed to develop a method for measuring eight alkenylbenzenes (eugenol, methyl eugenol, acetyl eugenol, trans-isoeugenol, safrole, estragole, myristicin and trans-anethole) in various spices using gas chromatography high-resolution mass spectrometry (GC–HRMS) with a simple ultrasonic vibration sample extraction method. The method was validated according to AOAC standards. The method had detection and quantification limits of 0.05 mg/kg and 0.15 mg/kg, respectively. The recovery ranged from 90.1% to 107% and the repeatability (RSD) ranged from 1.00% to 6.60% for all eight compounds, meeting the AOAC requirements. The analysis of 90 different dried and fresh spice samples revealed that eugenol (1.86–3581 mg/kg), trans-anethole (0.89–45.6 × 103 mg/kg) and estragole (0.19-248 mg/kg) were the main alkenylbenzenes, while trans-isoeugenol (0.69–7.86 mg/kg) and safrole (0.15–0.42 mg/kg) were the minor ones.

Unveiling the Chemical Profiling Antioxidant and Anti-Inflammatory Activities of Algerian Myrtus communis L. Essential Oils, and Exploring Molecular Docking to Predict the Inhibitory Compounds against Cyclooxygenase-2.

Considering the large spectrum of side effects caused by synthetic drugs and the development of natural alternatives utilizing Algerian flora, this study aimed to place a spotlight on the chemical profile and antioxidant and anti-inflammatory activities of Myrtus communis L. essential oils (MCEOs). In this study, essential oils (EOs) were collected via hydro-distillation of the plant's leaves, and a chemical constituent analysis was performed using gas chromatography-mass spectrophotometry (GC-MS). The in vitro antioxidant activity was evaluated using DPPH, ABTS, and hydroxyl radical scavenging tests. The in vitro anti-inflammatory capacity was estimated by studying the antidenaturation effect using bovine serum albumin (BSA) as a protein model. The in vivo anti-inflammatory activity was carried out by utilizing the classical model of carrageenan-induced paw edema in rats, using diclofenac (DCF) as the reference drug. Moreover, the molecular interaction of the compounds obtained from the GC-MS analysis was studied within the binding site of cyclooxygenase-2 (COX-2) using an in silico approach as the confirmatory tool of the in vitro and in vivo experiments. The GC-MS analysis revealed that MCEOs were mainly composed of oxygenated monoterpenes (70.56%), oxygenated sesquiterpenes (3.1%), sesquiterpenes (4.17%), and monoterpenes (8.75%). Furthermore, 1,8-cineole was the major compound (19.05%), followed by cis-geranyl acetate (11.74%), methyl eugenol (5.58%), α-terpineol (4.62%), and β-myrcene (4.40%). MCEOs exhibited remarkable concentration-dependent free radical scavenging activity, with an IC50 of 15.317 ± 0.340 µg/mL, 18.890 ± 2.190 µg/mL, and 31.877 ± 0.742 µg/mL for DPPH, ABTS, and hydroxyl radical, respectively. The significant in vitro anti-inflammatory activity due to the inhibition of BSA denaturation was proportional to the EO concentration, where the highest value was recorded at 100 μg/mL with an approximately 63.35% percentage inhibition and an IC50 of 60.351 ± 5.832 μg/mL. MCEOs showed a good in vivo anti-inflammatory effect by limiting the development of carrageenan-induced paw thickness. The in silico study indicated that, among the 60 compounds identified by the GC-MS analysis, 9 compounds were observed to have a high binding energy to cyclooxygenase-2 as compared to diclofenac. Our study revealed that EOs from Algerian Myrtus communis L. can be considered to be a promising candidate for alleviating many debilitating health problems and may provide new insights in the fields of drug design, agriculture, and the food industry.

Preparation of long-lasting releasing methyl eugenol fiber membrane and its trapping analysis on Bactrocera dorsalis

Methyl eugenol (ME) is a highly potent sexual attractant for Bactrocera dorsalis, which plays a crucial role in agricultural pest management. In this study, a composite fiber membrane was prepared by polystyrene (PS), polyethylene glycol diacrylate (PEGDA), and ME through electrostatic spinning respectively. The effective release period of ME was prolonged by triggering PEGDA with UV light. The mass ratio of PS to PEGDA affects the morphology of the fibers as well as the loading capacity (LC) and encapsulation efficiency (EE) for ME. Under optimal test conditions, the diameter of the fibers was 1.70 μm, and the ME loading capacity and encapsulation efficiency were (7.80 ± 0.07%) and (85.84 ± 7.94%). The combination of PS and PEGDA was confirmed by FTIR analysis, while its excellent thermal stability was verified through TGA testing. In the PS/PEGDA-ME-UV membrane, the cumulative release rate of ME reached 81.97% by week 8, which conformed to a first-order model. In the trapping experiments, a 53% rate of Bactrocera dorsalis capture was maintained even by week 8, demonstrating its potential for application in agricultural biocontrol.

Phenolic composition and antioxidant capacity of betel inflorescence extract in a simulated oral environment

The addition of betel inflorescence (BI) and slaked lime (calcium hydroxide) to betel quid (BQ) formulation may be detrimental to human health. Here, we assessed BI extracts prepared using artificial saliva or aqueous solution with or without adding slaked lime to mimic the release of phytochemicals from BI in the oral cavity. The extracts were also profiled by HPLC-DAD-ESI-QTOF-MS/MS to understand the quality and quantity of phytochemicals released. The results indicate that slaked lime facilitates the extraction of phenolics, likely due to a high pH. In a simulated oral environment with artificial saliva, the addition of slaked lime promotes the release of safrole, a well-known carcinogen. Dominant phytochemicals detected also include eugenol, acetyl eugenol and methyl eugenol, and only a fraction of these compounds is released in the simulated oral environment. This study reveals that environmental conditions can considerably affect the extraction of phytochemicals and triggers further investigation on how chewing practices may influence the release and activity of carcinogens.

Volatiles, phenolic compounds and bioactive properties of essential oil and aqueous extract of purple basil (Ocimum basilicum L.) and antidiabetic activity in streptozotocin-induced diabetic Wistar rats

Diabetes represents a significant global health concern, and researchers are actively exploring innovative approaches to managing this disease. In this study, we investigated the bioactive properties and anti-diabetic activity of the aqueous extract (BAE) and essential oil (BEO) derived from purple basil (Ocimum basilicum L.). The antioxidant activity of BAE was found to be higher than that of the essential oil extract from purple basil. Among the phenolic compounds identified, t-caffeic acid was the most abundant, followed by caftaric acid, kaempferol-3-glucoside, and quercetin-3-glucoside. In total, 49 volatile constituents were identified in cold- and hot-brewed basil, with methyl cinnamate, linalool, and eugenol were the major compounds. Both BAE and BEO showed inhibitory effect on the α-glucosidase and α-amylase enzymes. Furthermore, the administration of BAE led to a 37% reduction in blood glucose levels at day 14 and a 25.5% reduction at day 28. Similarly, BEO exhibited a 26.3% decrease in fasting blood glucose levels on the 28th day in rats. These findings highlight the potential of BAE and BEO in reducing blood glucose levels and their consequent antidiabetic activity. Based on the results obtained, we suggest that basil can be utilized in the formulation of functional and dietary foods within the food and beverage industry, owing to its demonstrated antidiabetic properties.

Synergism in Two-Component Insecticides with Dillapiole against Fall Armyworm.

The fall armyworm (Spodoptera frugiperda), a polyphagous insect pest, is a major threat to food production, rapidly spreading through all the tropical areas in the world. Resistance has developed to the control protocols used so far (pyrethroids, organophosphorus, and genetically modified plants), and alternative strategies must be found. The bioactivity in essential oils is usually associated with the major constituents, but synergistic interactions among the constituents (even minor ones) can improve the levels of activity considerably. Herein, we tested the insecticidal activity of several constituents of the essential oil from Piper aduncum, an Amazonian Piperaceae, both separately and as binary mixtures, through their application on the dorsal side of the larva pronotum. Dillapiole proved to be, isolated, the most active compound in this oil (LD50 = 0.35 ppm). In binary mixtures, a strong synergistic effect was observed for the pairs of dillapiole with β-caryophyllene (LD50 = 0.03 ppm), methyl eugenol (LD50 = 0.05 ppm), and α-humulene (LD50 = 0.05 ppm). In some cases, however, antagonism was recorded, as for dillapiole + β-pinene (LD50 = 0.44 ppm). The use of binary mixtures of essential oil constituents as low-environmental-toxicity insecticides allows a fine tuning of the insecticidal activity, and the exploitation of synergy effects.

Generation of Meaty Aroma from Onion (Allium cepa L.) with Polyporus umbellatus: Fermentation System, Sensory Profile, and Aroma Characterization.

One of the main reasons for consumer rejection of plant-based meat alternatives is the lack of meaty flavor after cooking. In this study, a platform was developed to generate meaty flavors solely from Allium substrates (chives, leeks, ramsons, and onions) using basidiomycete-mediated submerged fermentations. Polyporus umbellatus-mediated fermentation of onions resulted in an intense meaty and liver sausage-like flavor under proper fermentation parameters. Using multisolvent and solvent-free aroma extractions coupled with gas chromatography-mass spectrometry-olfactometry, 5 odorants with high assigned flavor dilution (FD) factors (≥ 256) were identified in the fermented sample that have been reported in the literature as important aroma compounds of meat products: methyl palmitate, bis(2-methyl-furyl) disulfide, (E,E)-2,4-decadienal, γ-nonalactone, and eugenol. Using selected ion monitoring, the presence of bis(2-methyl-furyl) disulfide (meaty, savory, FD 256) after fermentation was confirmed. It was proposed that P. umbellatus enzymatically forms bis(2-methyl-furyl) disulfide from intermediates derived from the thermal degradation of thiamine.

A Limiting Factor of Sex Attractants of Bactrocera dorsalis (Diptera: Tephritidae), Verified under Laboratory Conditions.

At present, sexual attractants mainly control insect populations by killing males. However, the effect of sex attractants may be limited by the mating ability of the attracted insects. The Oriental fruit fly, Bactrocera dorsalis (Hendel), has a strong reproductive capacity; it brings great losses to agricultural production, which can be controlled by methods using sex attractant methyl eugenol that mainly attracts males. Therefore, we studied the multiple and continuous (as well as consecutive) mating ability of B. dorsalis through behavioral experiments. The results show that male B. dorsalis can mate 11 times on average, with females mating only 1.93 times, and that 10.81% of males mate more than 20 times. The reproductive capacity of male B. dorsalis decreased significantly after four to five instances of continuous mating. In different mating patterns, the reproductive fitness of polyandry is not the highest, rather, interval mating is the best. A limiting factor of the sex attractant effect was revealed in B. dorsalis through behavioral evidence.

Methyl Eugenol (Parapheromone) Trapping System on Diversity of Fruit Flies and Influence of Weather Parameters on Trap Catches in Mango and Guava Cropping Systems

Studies on species diversity and influence of weather parameters on methyl eugenol (parapheromone) trap catches were carried out in mango and guava orchards at Coimbatore and Dindigul Districts of Tamil Nadu from Standard Meteorological Week (SMW) 16th to SMW 25th. Species diversity indices were calculated, and the methyl eugenol trap catches were correlated with the weather parameters. The results revealed that four fruit fly species viz., Oriental fruit fly, Bactrocera dorsalis (Hendel), Guava fruit fly, B. correcta (Bezii), B. caryeae (Kapoor), and Peach fruit fly, B. zonata (Saunders), were attracted to the parapheromone methyl eugenol traps. Among them the population of B. dorsalis was higher in both mango and guava orchards of Coimbatore and Dindigul Districts. The highest species diversity indices for fruit flies viz., Shannon H’ (0.936) and Simpsons D’ (0.593), evenness (0.468), and richness (0.482) were observed in guava orchard located in Coimbatore District, and the minimum diversity indices Shannon H’ (0.254), Simpsons D’ (0.921), evenness (0.160), and richness (0.291), were observed in mango orchard located in Dindigul District. The maximum number of fruit flies were trapped in 19th SMW in mango orchards in both Districts 134 and 145 flies/three traps, respectively. In Coimbatore District’s guava orchard and Dindigul District's mango orchard, trap catches revealed a significant positive correlation with rainfall. The subsequent weather parameters like max. temperature, min. temperature, wind speed, and relative humidity, were either positively or negatively correlated with trap catches in mango and guava orchards. In multiple regression analysis, the maximum predictability was seen in mango orchard (75.54%) located in Coimbatore District and the minimum (66.68%) in mango orchard located in Dindigul District.

Physicochemical characterization, polyphenols and flavonoids of different extracts from leaves of four varieties of tulsi (Ocimum sp.)

Leaves from four varieties of tulsi (Camphor, Krishna, Lavanga and Vishnu) were collected, dried and extracts were prepared using different solvents such as acetone, water, dichloromethane, ethanol, hexane and methanol. The total solids content in dried leaf powder was highest in Lavanga and Camphor, while Krishna showed the least. The study revealed that various secondary metabolites such as polyphenols and flavonoids were present in tulsi leaf extracts. The HPLC profiling showed the presence of rosmarinic acid in all the extracts irrespective of the solvent extraction. The other polyphenols present in the tulsi leaf extracts were p-coumaric acid, isothymucin, proto-catechic acid and caffeic acid. The GC-MS analysis of the extracts revealed methyl eugenol in Krishna variety with all the solvents, Bornanone in Lavanga and Camphor varieties in all the solvent extracts and caryophyllene in Vishnu variety. The LC-MS/MS profile of Krishna variety of tulsi showed mallic acid, citric acid, rosmarinic acid and asiatic acid as major compounds. The LC-MS/MS profile of Camphor variety of tulsi showed major peaks of compounds like mallic acid, citric acid, gallic acid, chlorogenic acid and asiatic acid. The LC-MS/MS profile of Lavanga variety of tulsi showed mallic acid, citric acid, gallic acid, asiatic acid and sumaresinolic acid as major compounds. Similarly in case of Vishnu variety, mallic acid, citric acid, gallic acid, apigenin, and sumaresinolic acid were present in majority. These phytochemicals from natural plant sources are known to possess many health benefits and considered as safe. Hence, these bioactive compounds may be explored for possible application as nutraceuticals.

Human Translesion Synthesis Polymerases polκ and polη Perform Error-Free Replication across N2-dG Methyleugenol and Estragole DNA Adducts.

The secondary metabolites of polypropanoids, methyleugenol (MEG), and estragole (EG), found in many herbs and spices, are commonly used as food flavoring agents and as ingredients in cosmetics. MEG and EG have been reported to cause hepatocarcinogenicity in rodents, human livers, and lung cells. The formation of N2-dG and N6-dA DNA adducts is primarily attributed to the carcinogenicity of these compounds. Therefore, these compounds have been classified as "possible human carcinogens" by the International Agency for Research on Cancer and "reasonably anticipated to be a human carcinogen" by the National Toxicology Program. Herein, we report the synthesis of the N2-MEG-dG and N2-EG-dG modified oligonucleotides to study the mutagenicity of these DNA adducts. Our studies show that N2-MEG-dG and N2-EG-dG could be bypassed by human translesion synthesis (TLS) polymerases hpolκ and hpolη in an error-free manner. The steady-state kinetics of dCTP incorporation by hpolκ across N2-MEG-dG and N2-EG-dG adducts show that the catalytic efficiencies (kcat/Km) were ∼2.5- and ∼4.4-fold higher, respectively, compared to the unmodified dG template. A full-length primer extension assay demonstrates that hpolκ exhibits better catalytic efficiency than hpolη. Molecular modeling and dynamics studies capturing pre-insertion, insertion, and post-insertion steps reveal the structural features associated with the efficient bypass of the N2-MEG-dG adduct by hpolκ and indicate the reorientation of the adduct in the active site allowing the successful insertion of the incoming nucleotide. Together, these results suggest that though hpolκ and hpolη perform error-free TLS across MEG and EG during DNA replication, the observed carcinogenicity of these adducts could be attributed to the involvement of other low fidelity polymerases.

A way forward for a sustainable active packaging solution for prolonging the freshness and shelf life of Rosa hybrida L. cut flowers

The study aimed to develop a paper-based approach as part of anti-microbial packaging to extend the shelf life of fresh-cut roses. To achieve this, a synergistic solution was developed from a mixture of bay, fenugreek, and lemon extract. A 1:1:1 ratio with an additional 3 % sucrose. It was found effective against Pseudomonas fluorescens, Salmonella typhimurium, and Enterobacter cloacae, which are the primary microorganism responsible for the spoilage of rose flowers. GCMS analysis shows that the presence of eugenol, oleic acid, ascorbic acid, caryophyllene, á-bisabolene, methyl eugenol, á-curcumene, humulene, and allene compounds contributed to the anti-microbial and antioxidant properties of the active matrix. The developed active matrix was coated on a kraft paper called Freshness Keeper (FK). FK paper was subjected to various characterization techniques, such as SEM, FTIR, and GCMS. The study revealed that the mechanical and barrier properties of the paper remained largely unchanged, except for the % elongation break and water absorptiveness. These changes were observed following the paper's coating with the matrix. The results suggest that the coating has the potential to affect the physical properties of the paper. To assess its effectiveness on the vase life and physiochemical characteristics of Rosa hybrida L. cut flowers were tested. The control flowers (without FK) displayed signs of wilting, color change, and bacterial growth after 10–12 d of storage at 2–4 ℃ with 85 % relative humidity. In contrast, the FK-wrapped flowers showed similar signs after 18–20 d of storage, effectively enhancing shelf life by an additional 8–10 d. Furthermore, the FK maintained the freshness and diameter of the cut rose bunches, while simultaneously maintaining the petal moisture content, petal color, and sensory attributes and controlling ethylene production. These results suggest that extending the shelf life of fresh-cut roses can reduce postharvest losses and add value to the flower industries, both domestically and in export markets.