Essential Oil Yield Research Articles

Improvement of essential oil yield and quality of Ajwain’s through foliar micronutrient application

Ajwain is an important seed spice crop, yielding an essential oil, which is a secondary metabolite and its accumulation is influenced by multiple factors. Micronutrients play a crucial role and influence the quality of essential oil. To assess the influence of micronutrients impact on essential oil yield, quality and composition an experiment was conducted at College of Horticulture, Bengaluru during rabi 2022-23. The experiment was laid out in Randomized complete block design comprising of 15 treatments and their combinations, which were administered as foliar sprays. Quality of the oil was analyzed through GC-MS. Foliar spray of 0.5% MnSO4 at 45 and 60 days after sowing recorded maximum thymol (65.54%); 0.5% CuSO4 at 45 DAS recoded highest essential oil content (2.84%); maximum essential oil yield was recorded in foliar spray of all micronutrients (29.39 kg ha-1). Foliar spray of micronutrients significantly impacted the accumulation of essential oil and thymol, which is the key component of ajwain oil.

Physicochemical characteristics and thin layer chromatography of the essential oil of spearmint: Mentha spicata L, from western Algeria

The species chosen for this study is sweet mint, Mentha spicata L, harvested in the wilaya of El Bayadh in Algeria. The aim of this work is to highlight the plant's identification criteria, its yield in essential oil, the various physico-chemical parameters and the composition of the essential oil using different techniques (determination of several chemical indices and establishment of the list of constituents of the essential oil using chromatographic methods). The botanical study showed the presence of two types of "Lamiaceae" type secretory hairs. These secretory hairs are the histological support for the production and storage of essential oils. A study of the kinetics of the extraction yield shows that distillation is rapid from 0 to 120 minutes, when the yield reaches an optimum (1.08%). The organoleptic characteristics and physico-chemical indices obtained are in line with the standards given in the bibliography. Thin layer chromatography revealed the presence of several constituents through the appearance of several spots of different colour and Rf, three of which were identified by comparison with controls, namely menthol, cineol and carvone.

Phaleria macrocarpa (Scheff.) Boerl. (Mahkota Dewa) seed essential oils: Extraction yield, volatile components, antibacterial, and antioxidant activities based on different solvents using Soxhlet extraction

Phaleria macrocarpa (Scheff.) Boerl., locally known as ‘Mahkota Dewa’, is a fruit commonly found in Malaysia. It demonstrates high potential for various biological activities, including antioxidant, anti-inflammatory, antibacterial, and anticancer properties. Nevertheless, there is a lack of research on the effect of essential oil extraction using different solvents on the antibacterial and antioxidant activities of this seed's fruit. This study aims to investigate the extraction yield, volatile components, antibacterial, and antioxidant activities of essential oil extracted from P. macrocarpa seeds using ethyl acetate, hexane, and petroleum ether as solvents. Gas chromatography-mass spectrometry was used to analyse the volatile components, while the antibacterial activity was assessed against Listeria innocua and Serratia marcescens. The antioxidant activity was evaluated using total phenolic content (TPC), total flavonoid content (TFC), and the 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay. Hexane showed the highest extraction yield (51.87 ± 0.21%), followed by petroleum ether (44.40 ± 0.14%) and ethyl acetate (27.08 ± 0.10%). The essential oils extracted with ethyl acetate, hexane, and petroleum ether contained 24, 26, and 21 volatile components, respectively. The major component, 1-(ethenylthio)-octane was found in concentrations ranging from 42.371 to 54.863 ppm, followed by 2,2-dimethyl-5-(3-methyl-2-oxiranyl)cyclohexanone, with concentrations between 30.771 and 40.783 ppm. The essential oil exhibited moderate antibacterial activity, as indicated by the zone of inhibition against L. innocua (8.00 ± 1.30 mm to 11.00 ± 1.40 mm) and S. marcescens (9.00 ± 1.00 mm to 14.00 ± 1.20 mm) compared to the positive control. Additionally, the essential oil demonstrated good antioxidant activity, with TPC, TFC, and DPPH values for hexane (65.56 ± 0.02 mg GAE/g, 4.46 ± 0.17 mg RE/g, 223.78 ± 29.69 μg/mL), ethyl acetate (72.99 ± 0.05 mg GAE/g, 19.47 ± 0.41 mg RE/g, 294.02 ± 12.70 μg/mL), and petroleum ether (70.29 ± 0.07 mg GAE/g, 4.83 ± 0.05 mg RE/g, 803.64 ± 27.76 μg/mL), respectively. Nonetheless, correlation analysis revealed a moderate relationship between DPPH and TFC. The essential oils from P. macrocarpa seeds demonstrates strong natural antibacterial and antioxidant potential, with hexane as the most efficient solvent. Exploring compounds like 1-(ethenylthio)-octane and 2,2-dimethyl-5-(3-methyl-2-oxiranyl)cyclohexanone may reveal medicinal applications and lead to innovative remedies.

Determination of Essential Oil Yields and Composition Lavender and Lavandin Cultivars (Lavandula sp.) Cultivated in Tuzlukçu, Konya

Lavender is an important medicinal plant, which used in many fields such as perfumery, cosmetics, medicine, aromatherapy and phytotherapy thanks to its high quality essential oils components. Hemus and Sevtapolis lavender cultivars of Lavandula angustifolia and Super A lavandin of Lavandula x intermedia were used in the study. The lavenders and lavandin were planted in 2022 in Tuzlukçu district of Konya province and harvested in 2023. Essential oils were obtained from the dried flowers of the plant. The essential oil components of the plant materials were measured by GC-MS. The essential oil yield of Lavandula angustifolia cv. Hemus was 2.65%, that of Lavandula angustifolia cv. Sevtapolis was 2.14% and that of Lavandula x intermedia cv. Super A was 7.95%. In the Hemus cultivar of lavender, the concentration of linalyl acetate was 19.76%, linalool was 39.09%, and camphor, an undesired component in lavender essential oil, amounted to 0.41%. Meanwhile, the Sevtapolis cultivars contained 10.64% linalyl acetate, 40.41% linalool and 0.47% camphor. In Lavandin (Super A) cultivar contained 30.39% linalyl acetate, 30.29% linalool, and 6.71% camphor.

Essential Oil of Eucalyptus: A Natural Solution for Treating Pediculosis

Objective: Pediculosis is a condition caused by the infestation of Pediculus Humanus Capitis. The pesticides used in current formulations exhibit toxicity and carcinogenic effects on consumers. This study aimed to investigate the pediculicidal activity of the essential oil from Eucalyptus Globulus leaves, with the intention of adding it as an active ingredient in pediculicidal formulations to replace harmful chemicals.
 Design/methodology/approach: In vivo tests were conducted to assess the repellency and mortality of the essential oil obtained through hydrodistillation. The major components were determined through gas chromatography-mass spectrometry analysis. Additionally, proximate, and chemical composition analyses were performed on the eucalyptus leaves using ASTM E871, ASTM E872, ASTM D1104, TAPPI T264, TAPPI T207, ASTM D1106, and ASTM D1104 methods.
 Results: A repellency of 66.66% and 100% mortality within 2.26 minutes were obtained in the in vivo tests. The yield of hydrodistilled essential oil was 4 mL/kg, primarily composed of 71.04% 1,8-cineole, 18.94% 4-Ethyl-m-xylene, 2.72% γ-Terpinene, and 1.23% L-α-Pinene. Furthermore, the composition of eucalyptus leaves was determined as 61.25% moisture, 30.32% volatile matter, 6% ash, 2.40% fixed carbon, 11.22% acetone extractives, 33.03% water extractives, 31.49% lignin, 69.33% holocellulose, 62.09% cellulose, and 7.24% hemicellulose.
 Limitations on study/implications: The pediculicidal activity study was conducted solely on the essential oil, and further testing on the formulation of the finished product is necessary.
 Findings/conclusions: The pediculicidal activity study was conducted solely on the essential oil, and further testing on the formulation of the finished product is necessary.

Coconut Juice Enhances Rooting and Leaf Essential Oils of Juniperus sabina L. Cuttings

Juniperus sabina L. (J. sabina L.) represents a compelling forest species due to the presence of metabolites in its leaves, which possess diverse applications in the fields of cosmetics, pharmaceuticals, and medicine. However, the species presents difficulties with regard to natural regeneration. This research aimed to improve the propagation conditions of J. sabina by using cuttings to enhance both the rooting percentage and essential oil (EO) content in the leaves. To do this, sampled cuttings underwent pretreatment with four different doses of coconut juice (25%, 50%, 75%, and 100%) within four substrates or rooting media, namely perlite, mixed substrate, pumice, and perlite–cocopeat. The study was carried out over the course of all four growing seasons to examine the impact of harvesting time as well. The best results for rooting were observed with the pretreatment of coconut juice at 25% in spring and in the substrate of perlite–cocopeat (37.10% rooting). The coconut juice also significantly increased the percentage of EOs in spring (0.82% of essential oil yield). Beta-pinene was the essential oil component with the highest representation (34.7% in fall), whereas in the spring, the best season to collect cuttings, the dominant component was nerodiol. Our study can contribute to the planning of culture systems using cuttings and to the control of the production of EOs from the leaves of J. sabina.

Hydrodistillation of essential oil from peels of orange (Citrus sinensis) in the Mekong Delta, Vietnam: process optimization and chemical profiling

In this study, essential oils were extracted from peels of orange (Citrus sinensis) by employing hydrodistillation. The materials were collected in Ben Tre Province, Vietnam and the process was optimized by varying some experimental parameters including temperature, water-to-material ratio, extraction time and material size. The obtained essential oil was analyzed by Gas Chromatography-Mass Spectrometry to determine chemical composition. The maximal essential oil yield was determined as approximately 4%, obtained at the following conditions: ratio of water and lemon peels of 3:1 (mL/g), 60 mins and130°C. GC-MS results revealed that Limonene (98.454%), β-Myrcene (0.997%), and α-Pinene (0.549%) are the major constituents in the essential oil.

IMPACT OF NITROGEN FERTILIZER ON THE PRODUCTIVITY AND QUALITATIVE PARAMETERS OF ANISE (Pimpinella anisum L.)

The present study investigated the effects of nitrogen fertilization on the yield and quality characteristics of Anise (Pimpinella anisum L.). The study was conducted in the ecological conditions of Kahramanmaras from 2019 to 2021. Two different anise populations Izmir (P1) and Konya (P2) and six different nitrogen fertilizer doses (0, 30, 60, 90, 120, 150 kg ha-1) were used in the study. The experiment was set up in triplicate using a split-plot design, with the populations on the main plots and the fertilizer doses on the subplots. Considering the herbal properties of anise grown in different nitrogen dose applications; plant height was 41.71- 42.75 cm, the total number of branches (10.62-12.50 plants-1), fruit branches (4.78-5.29 plants-1) and umbrellas (8.12-9.64 plants-1) were recorded. Considering the yield and quality characteristics; seed yield the range was 350.10- 400.02 kg ha-1, 1000-seed weight 2.78-3.49 g, protein rate 15.3-17.77%, fixed oil rate 15.15-16.34% fixed oil yield 50.51-60.48 kg ha-1, essential oil rate 1.66-2.26%, and essential oil yield 5.80-8.90 L ha-1. The Konya population had higher values in terms of seed yield and quality characteristics. With the exception of plant height, which revealed the total number of branches, fruit branches, umbels, seed yield, thousand seed weight, protein ratio, fixed oil ratio, fixed oil yield, essential oil ratio, and essential oil yield, all of the studied characteristics generally showed improvement with an increase in nitrogen doses. However, a nitrogen treatment of 120 kg ha-1 produced the maximum seed production.

The Effect of Utilizing Different Types of Organic and Bio-Fertilizers on Growth, Elements Concentration, Seed Yield and Essential Oil of Coriandrum sativum L.

Background: Bio-fertilizers may be used to maintain soil fertility and soil improvement. Methods: In this study involving 12 treatments and 3 replications was conducted in Tehran, Iran. The experiment was conducted in 2018–2019 as a randomized complete block design. The treatments were 1- vermicompost (10 t/ha), 2- nitroxin, 3- bio-superphosphate, 4- biosulfur, 5- vermicompost + nitroxin, 6- vermicompost + bio-superphosphate, 7- vermicompost + biosulfur, 8- nitroxin + bio-superphosphate, 9- nitroxin + biosulfur, 10- bio-superphosphate + biosulfur, 11- chemical fertilizer and 12- control (without fertilizer). Result: The results showed that the treatments had a significant impact on the characteristics examined such as the highest plant height (75.3 cm) in the treatment combining vermicompost and biological superphosphate and the highest number of shoots/plant. The highest concentration of N in seeds (2.92%) was obtained when plants were treated with nitroxin and biosulfur and the highest concentration of P in seeds (0.83%) when treated with biological superphosphate. In addition, the highest K content in seeds (4.06%) and grain yield (1297.5 kg.ha-1) were found in the treatment of nitroxin and bio-superphosphate, as well as the content of essential oil (0.32%). and the yield of essential oils (2.89 kg.ha-1) was obtained when treated with nitroxin. Consequently, Bio-organic fertilizers can be considered as an alternative to chemical fertilizers in organic coriander cultivation.

Chemical Diversity of Wild-Growing and Cultivated Common Valerian (Valeriana officinalis L. s.l.) Originating from Poland.

Common valerian is a medicinal plant. The underground organs of this species are used as a mild sedative and sleeping aid. Poland is one of the largest producers of this raw material in Europe, with local cultivar 'Lubelski' as a primary cultivated form. Although valerian is the subject of more or less deliberate selection carried out by farmers, it is still genetically unstable. The aim of this study was to determine the diversity of the 'Lubelski' cultivar originating from four regions of Poland (forms: L1-L4) in relation to wild-growing populations of the species. The plants were assessed in terms of the mass of underground organs and the content of valerenic acids and essential oils (EOs). The content of valerenic acids was determined using HPLC, whereas the content of EOs was determined using hydrodistillation. The composition of EOs was assessed using GC-MS GC-FID. The ploidy level of the analyzed objects was determined as well. Wild-growing populations (diploids) were characterized by lower masses of underground organs and lower contents of valerenic acid than cultivated forms (tetraploids). However, they produced higher contents of EOs. All the cultivated forms were strongly diversified with respect to the analyzed traits, including the mass of the roots (CV 49-75%), the content of valerenic acids (CV 18-55%), and the content of EOs (CV 28-57%). A total of 44 compounds were identified in the EOs. The dominant compound of both wild-growing populations and the 'Lubelski' forms were: α-fenchene, bornyl acetate, and valerenal. Among 'Lubelski' forms, the most interesting seems to be the L2 form, which was characterized by a relatively high yield and high content of valerenic acids and EOs. Thus, it appears to be a promising source of objects for further valerian cultivar improvement.

Organic vs. Conventional Farming of Lavender: Effect on Yield, Phytochemicals and Essential Oil Composition

Increasing prices and market demand for organic products are stimulants of organic farming. However, this sector is a challenge for producers and further improvements are still necessary. The present study case was conducted to compare the effects of organic (OF) and conventional (CF) farming on lavender (Lavandula angustifolia Mill.) oil yield, plant pigments and essential oil composition. The study was conducted for two years in the period 2019–2020. Six private farms were included in the experiment with conventional and organic agriculture systems. They are located in Kazanlak Valley, Southern Bulgaria. Organic lavender inflorescences were determined to have chlorophyll a and total chlorophyll within a narrow range between 251.3 and 275.7 μg·g−1 and between 375.5 and 487.0 μg·g−1 compared to conventional ones—between 245.9 and 377.5 μg·g−1 and 385.3 and 595.4 μg·g−1 respectively. However, carotenoids and anthocyanins were in a wide range in organic lavender between 36.9 and 72.2 μg·g−1 and 410 and 1240 µg cyn-3-gly.g−1 compared to conventional ones—between 55.5 and 77.3 μg·g−1 and 200 and 780 µg cyn-3-gly.g−1, respectively, for both studied years. The key constituents in essential oil were linalyl acetate (28.42–38.23%), linalool (20.01–31.04%) and β-caryophyllene (7.95–14.97%). The composition was compared with the parameters set out in the international standard for lavender oil. The influence of the type of agricultural system on essential oil yield and its composition was not found. According to the obtained results, levels of chlorophyll a, chlorophyll b and total chlorophyll were higher in conventional farming than in organic farming for the second year of the study.

Spearmint (Mentha spicata L.) leaves essential oil: Comparative compositional and biological attributes as a function of different agroclimatic regions

In the current work, the biological potential of spearmint leaves essential oil (EO), including its antioxidant, antibacterial, and hemolytic properties, are described together with its chemical composition. The spearmint leaves were gathered in Punjab, Pakistan's hilly, dry, irrigated, and drought-stricken agroclimatic zones. From examined leaves from various locales, the hydro-distillation process produced an EO yield that ranged from 0.41% to 0.76%. In recovered EOs, GCMS compositional analysis identified 31 components, with carvone (27.4%–47.2%), menthone (1.0%–23.9%), menthol (3.0%–14.5%), limonene (2.4%–93%), and 1,8-cineol (0.6–8.5%) being the predominant constituents. The investigated oils displayed high levels of total phenolics (30.9–34.3 g GAE/100g), flavonoids (4.6–10.1 g CE/100g), and DPPH radical scavenging capacity (12.5–17.1 g mL−1) as well as linoleic acid peroxidation inhibition (57.1–62.6%). Against particular types of bacteria and fungus, the studied EO demonstrated considerable antibacterial activity (AMA). EO extracted from a sample of a location under drought stress (Layyah) shown greater AMA, while EO from hilly regions (Murree) displayed higher antioxidant potential, total phenolics (TP), flavonoids (TF), and hemolytic activity (HA). This study recommends the use of spearmint leaves as an effective natural antioxidant and antibacterial ingredient in the development of nutra-pharmaceutical products and dietary supplements.

Extraction conditions, chemical composition and biological activity of essential oil of Allium schoenoprasum L. bulb from Quang Tri province, Vietnam

This paper presents a comprehensive investigation on the extraction of essential oil from Allium schoenoprasum L. (AS) bulbs collected in Quang Tri province, Vietnam. Effects of extracting conditions on the quantity of extracted essential oil were investigated, followed by the evaluation of physicochemical characteristics, chemical composition and biological activities. The hydro-distillation process under suitable extracting conditions (extraction time of 3 h, NaCl concentration of 5 %, material-to-NaCl solution ratio of 1:2) allowed obtaining the highest essential oil yield of 0.290 ± 0.003 %. Chemical composition analysis (Quadrupole GC/MS) of the AS bulb essential oil in xylene indicated that disulfide and trisulfide compounds, as major components, accounted for 97.53 % of the identified compounds. The obtained AS bulb essential oil exhibited high antioxidant activity, which is significantly higher than that of ascorbic acid, in the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical test. Moreover, it provided strong antibacterial activity against Escherichia coli, methicillin−resistant Staphylococcus aureus, methicillin sensitive Staphylococcus aureus and moderate inhibition activity against carbapenem-resistant Pseudomonas aeruginosa and Streptococcus pneumoniae.

DAYA PROTEKSI LOTION DENGAN MINYAK ATSIRI SERAI DAPUR (Cymbopogon citratus) TERHADAP NYAMUK Aedes aegypti

Lemongrass consists of two types that have many benefits. Its use in research or in processing using its stems alone causes lemongrass leaf waste which can be used as an essential oil and used as an anti-mosquito lotion to reduce the use of chemicals as repellent. The purpose of this study was to determine the yield of lemongrass essential oil, to determine the protective power of each concentration of citronella essential oil in lotion in repelling mosquito bites, and to determine the level of preference for mosquito repellent lotion. The average yield with three repetitions followed by standard deviation (SD) was 0.1% ± 0.0024% b/b. Lotion preparation provides different protection during 6 hours of exposure, namely K- and F1 no protection, F2 for 2 hours, F3 and K+ 4 hours and F4 5 hours. Based on all parameters, the most preferred formulation is F1 and does not give sensitive reactions. Keyword: Aedes aegypti, essential oils, lemongrass, lotions.

New insights into the chemical composition of Piper spp. collected in the northern region of Vietnam

Our study aimed to compare the essential oil composition of Piper species (Piperaceae) collected in the northern region of Vietnam and find possible fingerprints of different species. The aerial parts of seven Piper species including P. mutabile, P. leptostachyum, P. laosanum, P. boehmeriifolium, P. carnibracteum, P. albispicum, and P. longum were collected, shade-dried and chopped into small pieces before being submitted to the hydrodistillation of essential oils. The yields of essential oils ranged from 0.12 to 0.85%. GC-MS analysis of the essential oils led to the identification of 99 volatile components, accounting for 92.5–99.6% of the total oils. Sesquiterpenes (40.3–93.0%) were commanding in all essential oils while monoterpenes were only dominant in essential oils from P. albispicum (29.8%) and P. longum (29.4%). The distances between groups of seven Piper essential oils were measured using multivariate analysis. Elemene isomer seems to be the characteristic compound of all seven Piper essential oils. Besides, the essential oil from P. mutabile in the present study was characterized by the very high content of safrole (20.9%) while epi-γ-eudesmol (15.9%), cis-caryophyllene (14.4%), trans-caryophyllene (10.6%), guaiol acetate (10.1%), eremophilene (9.6%) were main components in essential oil from P. laosanum. Essential oil of P. boehmeriifolium was dominated by elemene isomer (15.6%), eremophilene (14.2%), and trans-caryophyllene (9.3%). Essential oil from P. albispicum in our study featured by high contents of eremophilene (11.1%) and β-pinene (10.1%). In the other hand, essential oil from P. carnibracteum was characterized by the dominant amount of trans-caryophyllene (21.7%), α-muurolene (21.1%), bicyclo[4.3.0]nonane,7-methylene-2,4,4-trimethyl-2-vinyl- (17.8%) while aromadendrene (25.7%), γ-cadinene (20.3%) were ascendant in essential oil from P. leptostachyum. To the best of our knowledge, this is the first time that the essential oil composition of P. leptostachyum and P. carnibracteum were investigated. Besides, the volatile components in the essential oils from P. albispicum, P. laosanum, and P. mutabile showed some differences in the comparison to the data published previously on the chemical composition of these aforesaid species which could depend on many factors.

Effect of drying techniques on essential oil yield and their quality of lemongrass [Cymbopogon flexuosus (Nees ex Steud) Wats] cultivars Krishna and CKP-25

An experiment was conducted on popularly cultivated two cultivars (cv.Krishna and cv. CKP-25) of Lemongrass (C. flexuous [Nees ex Steud) Wats] at FFDC, Kannauj in August 2015 and replicated in February 2016 to examine the effect on different drying techniques by adopting other parameters. The study recorded different parameters at intervals of 7 days during plantation. Cultivar Krishna was more favourable in herbage yield, oil percentage, and oil yield than cv. CKP-25.The semi-dried condition of CV. Krishna was found to be highest in oil percentage, i.e., 1.5 ± 0.08%, followed by shade and sun-shade-dried oil percentage was found as 1.4 ± 0.07% each, and the most negligible value was by fresh leaves, i.e., 0.7 ± 0.03%, whereas cv. CKP-25 oil percentages in semi-dried and shade-dried were found to be highest at 0.9 ± 0.05% each; sun-shade-dried and fresh leaves were 0.8 ± 0.04% and 0.6 ± 0.03%, respectively. In physical analysis, the value of cv. Krishna showed optical rotation in the ranges of -3.0 to -1.62, a refractive index of 1.4785 to 1.4791 at 27 °C, and a specific gravity of 0.8901- 0.8932 at 27°C. However, cv. CKP-25 showed optical rotation in the ranges of -2.4 to -1.31, a refractive index of 1.4724- 1.4829 at 27 °C, and a Specific gravity of 0.8819- 0.8854. All the values were under the range of BIS standards. In an instrumental analysis of the GLC report, citral content was recorded cv. CKP-25 showed a higher citral content of 83.95% in semi-dried conditions than cv. Krishna of 74.5%. The cv. (Krishna) in sun-shade dried, had 79.88%, followed by shade-dried at 76.83% and fresh leaves at 75.71%. Whereas, in cv. CKP-25, sun-shade-dried 83.24%, shade-dried 82.19%, and freshly harvested leaves showed 76.31% citral content, respectively. Keywords: Citral content, CKP-25, Cymbopogon flexuosus cv. Krishna, Drying methods, Lemongrass, Oil percentage, Physical analysis

Response surface optimization and support vector regression modeling of microwave-assisted essential oil extraction from cumin seeds

The current research involved creating models using Response Surface Methodology (RSM) and Support Vector Regression (SVR) to forecast the amount of extractable essential oil that can be obtained from powdered cumin seeds. Influence of microwave power (140–280–420–560–700 W), amount of water (500–600–700–800–900 ml), duration of distillation (30–45–60–75–90 min) and soak time (15–30–45–60–75 min) on essential oil yield were investigated. Microwave Assisted Extraction (MAE) allowed higher recoveries compared to conventional Soxhlet extraction, without altering the chemical components of the extract. A five-level four FCC experimental design was developed using Minitab (15.1.20.0). A total of 31 runs were performed in microwave-assisted extraction apparatus. Experimental data obtained was then used for developing RSM and SVR models for the prediction of the yield of essential oil. The optimum conditions for maximum yield of cumin oil were given by RSM. Maximum yield of 3.4 ml (0.017 ml/g) was found at 140 W of microwave power, 500 ml of water, 90 min duration of distillation, and 15 min of soak time. In this work, epsilon SVR with RBF kernel was used. The grid search (depth-first search) methodology was applied for tuning the values of epsilon, gamma, and cost using the LIBSVM module on the MATLAB interface. The statistical parameters namely, average absolute relative error (AARE), coefficient of determination (R2), standard deviation (SD), and root mean square error (RMSE) were selected as the performance parameters. The developed SVR model was compared with the RSM model. The AARE values of 2.27% and 1.29%, R2 values of 0.86 and 0.99, SD values of 1.73 and 0.29, and RMSE values of 0.0284 and 0.0132 were obtained for RSM and SVR models respectively. It is found that SVR is more accurate and better tool for modeling of MAE process.

OBTAINING BALSAMIC POPLAR BUD ESSENTIAL OIL BY THE BAROTHERMAL METHOD AND STUDYING THE EFFECT OF ITS AQUEOUS EMULSIONS ON SEED GERMINATION AND GROWTH OF TOMATO PLANTS

In recent years, there has been a persistent search for new methods and technologies for cultivating specific crops to increase their productivity and improve product quality. The aim of the study was to obtain essential oil from poplar buds by the barothermal method, to standardize the obtained essential oil, to study the effect of an aqueous emulsion of poplar oil on the growth and development of tomato seeds. For obtaining the maximum yield of balsam poplar essential oil, the optimum pressure, input of raw material, and processing time were investigated. The essential poplar oil was standardized according to organoleptic and physico-chemical parameters. The study found that the use of an aqueous emulsion of poplar bud oil had a significant impact on the morphogenesis, physiological and biochemical parameters of tomato seeds.

Synthetic polyploid induction influences morphological, physiological, and photosynthetic characteristics in Melissa officinalis L.

Melissa officinalis L., a well-known herb with diverse industrial and ethnopharmacological properties. Although, there has been a significant lack in the breeding attempts of this invaluable herb. This study aimed to enhance the agronomical traits of M. officinalis through in vitro polyploidization. Nodal segments were micropropagated and subjected to oryzalin treatment at concentrations of 20, 40, and 60 mM for 24 and 48 hours. Flow cytometry, chromosome counting, and stomatal characteristics were employed to confirm the ploidy level of the surviving plants. The survival rate of the treated explants decreased exponentially with increasing oryzalin concentration and duration. The highest polyploid induction rate (8%) was achieved with 40 mM oryzalin treatment for 24 hours. The induced tetraploid plants exhibited vigorous growth, characterized by longer shoots, larger leaves, and a higher leaf count. Chlorophyll content and fluorescence parameters elucidated disparities in photosynthetic performance between diploid and tetraploid genotypes. Tetraploid plants demonstrated a 75% increase in average essential oil yield, attributed to the significantly larger size of peltate trichomes. Analysis of essential oil composition in diploid and tetraploid plants indicated the presence of three major components: geranial, neral, and citronellal. While citronellal remained consistent, geranial and neral increased by 11.06% and 9.49%, respectively, in the tetraploid population. This effective methodology, utilizing oryzalin as an anti-mitotic agent for polyploid induction in M. officinalis, resulted in a polyploid genotype with superior morpho-physiological traits. The polyploid lemon balm generated through this method has the potential to meet commercial demands and contribute significantly to the improvement of lemon balm cultivation.

Boosting the essential oil yield of Coriandrum sativum L. using choline chloride-based NADES: an optimized and systematic study employing response surface methodology (RSM)

Coriander essential oil (CEO) is one of the most versatile and powerful essential oils used in the food and pharmaceutical industries, thanks to its numerous properties. Different choline chloride-based natural deep eutectic solvents (NADES) were studied as additives in the hydrodistillation preparation of CEO, and most were able to increase oil yield compared to conventional hydrodistillation. Among these different NADES, the use of choline chloride (ChCl)-urea (N11) led to a yield increase of up to 31.5% in comparison to traditional water hydrodistillation. Few differences were observed in the composition of the oils, except in those prepared using acidic ChCl-citric acid NADES, which led to a significant variation in the CEO composition. The phytochemical profile of CEOs was investigated, and the enantiomeric fractions (EFs) of the most important monoterpene alcohol, linalool, were determined. No differences in the EFs were observed for all the CEOs (86.77% (S)-(+) enantiomer), except for those obtained by using choline ChCl-citric acid (59.26% (S)-(+) enantiomer). Subsequently, a three-level custom design (CD) was used to study the influence of four independent variables: plant-to-N11 ratio, pre-treatment temperature, pre-treatment time, and water percentage. The response surface methodology (RSM) was used to evaluate and optimize the effects of the chosen factors. The RSM results show that the plant-to-N11 ratio, pre-treatment temperature, and water percentage were highly significant in influencing the extraction yield, while the pre-treatment time was not a significant influence. The highest extraction efficiency was obtained using N11 in a 1:4 (w/w) plant-to-NADES ratio, 40 °C and 30 min US-assisted pre-treatment, and 30% (w/w) water content, resulting in an additional 26.6% increase compared with the screening phase. Overall, using the optimized conditions, we were able to enhance the extraction yield up to a total of a 63% (0.77 ± 0.04% (CEOref) vs. 1.10 ± 0.09% (CEOopt)).