Seeds Essential Oil Research Articles

MALAYSIAN JOURNAL OF CHEMISTRY (MJChem) MJChem is double-blind peer reviewed journal published by the Malaysian Institute of Chemistry (Institut Kimia Malaysia) E-ISSN: 2550-1658 About Editor Reader Author Reviewer Register Login Vol 26 No 5 (2024): Malaysian Journal of Chemistry Date Published: 21 October 2024 Antioxidant and Antibacterial Activities of Coriander (Coriander sativum L.) Seeds Essential Oil Mazlin Mohideen*, Anis Mohd

MALAYSIAN JOURNAL OF CHEMISTRY (MJChem) MJChem is double-blind peer reviewed journal published by the Malaysian Institute of Chemistry (Institut Kimia Malaysia) E-ISSN: 2550-1658 About Editor Reader Author Reviewer Register Login Vol 26 No 5 (2024): Malaysian Journal of Chemistry Date Published: 21 October 2024 Antioxidant and Antibacterial Activities of Coriander (Coriander sativum L.) Seeds Essential Oil Mazlin Mohideen*, Anis Mohd

Assessment of Phytochemical Properties of Nigella sativa Seeds Essential Oil and Its Potential Antimicrobial Activity against Staphylococcus aureus in the Context of Safety Profiles and Therapeutic Applications in Neurosurgical Interventions

This comprehensive study explored the phytochemical properties of Nigella sativa L (N. sativa L) seeds essential oil using gas chromatography-mass spectrometry (GC-MS) analysis, with a specific focus on its potential compound Thymoquinone (TQ) exhibiting antimicrobial activity against Staphylococcus aureus (S. aureus) in the context of neurosurgical interventions.The study employs a meticulous methodology, encompassing the preparation of N. sativa essential oil, qualitative phytochemical screening, quantitative GC-MS analysis, and the antimicrobial analysis, employing Disc Diffusion, Minimum Inhibitory Concentration (MIC), and Minimum Bactericidal Concentration (MBC) evaluations to demonstrate the substantial inhibitory and bactericidal effects against Staphylococcus aureus (S.aureus}. comprehensive assessment of antimicrobial activity.The qualitative analysis reveals the presence of alkaloids, flavonoids, phenols, tannins, cardiac glycosides, steroids, saponins, and terpenoids, underscoring the multifaceted pharmacological potential of the essential oil. The quantitative GC-MS analysis provides a detailed breakdown of the chemical composition under different extraction conditions, showcasing the complexity of N. sativa essential oil. The study thoroughly compares the antimicrobial efficacy of N. sativa essential oil with various antibiotics, employing Disc Diffusion, MIC, and MBC analyses. N. sativa demonstrates substantial inhibitory effects, with a 29 mm zone comparable to Gentamycin. The MIC and MBC values align with established antibiotics, indicating similar bacteriostatic and bactericidal properties. Despite slightly lower potency than Vancomycin and Methicillin, N. sativa exhibits considerable antimicrobial effectiveness. This study contributes valuable insights into the phytochemical composition of N. sativa seeds essential oil and its potential as an antimicrobial agent in the context of neurosurgical interventions paves the way for future research.

Characterization and Antioxidant Activity Assay of Essential Oil Parts of Rosella (Hibiscus sabdariffa L.)

Rosella (Hibiscus sabdariffa L.) is known as a plant whose calyx contain high levels of antioxidant bioactive compounds and good inhibitory power against free radicals. However, other parts of the rosella plant have not yet been utilized for their antioxidant content and activity. The aim of this research is to compare the profiles of essential oils of parts of the rosella plant (seeds, leaves and flower petals) and their antioxidant activity. This research method begins with the process of extracting essential oils using the water-steam distillation method. Furthermore, the profile of the essential oil is known from the results of yield calculations and characterization using the GC-MS instrument. The antioxidant activity was tested using the DPPH method. The yield of essential oils obtained was 0.0107% for seeds, 0.0087% for leaves and 0.0136% for flower petals. GC-MS characterization shows that the most abundant chemical components contained in the essential oils of seeds, leaves, and flower petals are fatty acid compounds (2-propanoic acid, butanoic acid, hexanoic acid) and esters (neopentyl isobutyrate). The results of the antioxidant activity test showed the IC50 value for each essential oil, namely, seeds: 30.15 μg/ml, leaves: 171.27 μg/ml and flower petals: 126.58 μg/ml. The compound characteristics obtained showed the best results for rosella seed essential oil, this was supported by the fairly high antioxidant activity test results IC50 <50 μg/ml. Keywords: Antioxidant activity, Characterization, Essential oils, IC50, Yield.

Studying the effectiveness of Jatropha carcus L. Extract as a repellent, antifeedant, and toxic substance against red palm weevil (Rhynchophorus Ferrugineus) adult insects in Saudi Arabia

ObjectiveRed palm weevil (RPW), Rhynchophorus ferrugineus, is a highly harmful pest that causes severe damage to date palm trees. The detrimental influence of RPW on date palm trees cannot be ignored and must be addressed. Chemical insecticides are available for controlling RPW; however, the insect population has become resistant to these chemicals, leading to damage and spread to new areas. The present investigation examined the impacts of physic nut (Jatropha curcas L.) seeds essential oils (PNEO) on laboratory-reared RPWs adult insects reared in a controlled laboratory environment. MethodsThe insecticidal, repellent, and antifeedant potentials of different doses (10, 20, 30, 40, 50%) of PNEO were tested against RPW. The insecticidal activity of J. curcas seeds oil extracts was assessed using topical application and feeding methods. ResultsRPW showed a high mortality rate when J. curcas seeds oil was applied topically after 24 h (P < 0.05). The mortality (%) of insects was 8, 76, 92, 96, and 100 for 10 %, 20 %, 30 %, 40 %, and 50 % concentrations, respectively. The LC50 and LC90 were 16.50 %, and 28.14 %, respectively. Results from the feeding method demonstrated a significant increase in mortality with a 100 % mortality rate at higher concentrations of PNEO compared to 10 and 20 % concentrations (P < 0.0001). The LC50 and LC90 were 24.42 % and 31.30 %, respectively. There was no significant decrease in food consumption and the antifeedant index when 10 % and 20 % of J. curcas seeds oil were used on the 3rd and 6th day after application. All J. curcas oil concentrations showed a repellent effect significantly higher than the controls (P < 0.05). ConclusionJ. curcas seeds oil has shown potential insecticidal and repellent effects against RPW, and it could provide an eco-friendly tool for RPW pest management.

Chemical Composition and Bioactivity of Dill Seed (Anethum graveolens L.) Essential Oil from Plants Grown under Shading

This study determined the content and composition of dill seed (Anethum graveolens L.) essential oil under varying light conditions: non-shaded plants in open fields and plants covered with pearl shade nets (40% shade index). Essential oil was extracted using Clevenger hydrodistillation. The essential oil content was 4.63% for non-shaded plants and 4.81% for shaded plants. GC/MS analysis revealed twenty-one and twenty-two components in dill seed from non-shaded and shaded plants, respectively. The terpenic fraction of essential oil from non-shaded plants consisted mainly of oxygen-containing monoterpene derivatives (53.6%), with carvone (46.1%) as the primary component, followed by monoterpene hydrocarbons (46.4%), predominantly limonene (43.8%). Essential oil from shaded plants contained a higher content of carvone (49.8%) and a lower content of limonene (37.8%) compared to essential oil from non-shaded plants. Non-shaded plant essential oil exhibited stronger antioxidant activity (EC50 value: 26.04 mg mL−1) than shaded plant essential oil (54.23 mg mL−1). Dill seed essential oil showed the most potent antimicrobial activity (disc diffusion method) against Escherichia coli (inhibition zone: 15–18 mm). Shaded plants demonstrated a positive influence of essential oil against Klebsiella pneumoniae. Carvone and its derivatives, as the main components, hold significant potential in the food industry and alternative medicines. A practical implication of this study could be higher plant densities or intercropping of dill, as it thrives with minimal light.

Chemical characterization and antifungal potential of Trigonella foenum-graecum L. followed by molecular docking studies

The present study involves the chemical characterization and antifungal potential of fenugreek Trigonella foenum-graecum L. (fenugreek) seeds/leaves essential oils and their major constituents along with computational molecular docking calculations. The fenugreek seeds and leaves essential oils were extracted by hydro-distillation and characterized by Gas chromatography-mass spectrometry and Gas chromatography-flame ionization detector. Benzyl acetate (51.70%) and γ-tocopherol (42.09%), the major compounds in fenugreek seeds and leaves essential oils respectively were isolated by column chromatography. The essential oils and their major compounds were investigated for their antifungal activity against Rhizoctonia solani and Drechslera oryzae by the Poison food technique. Among all the treatments, fenugreek leaves essential oil was the most effective with ED50 values of 850 and 1120 ppm against R. solani and D. oryzae respectively. All the treatments were found more effective against R. solani than D. oryzae. Molecular docking studies of the major compounds present in the essential oils against R. solani agglutinin (PDB ID 4G9N and 4G9M) suggested that 9,19-cyclolanost-24-en-3-ol present in abundance in fenugreek leaves essential oil than the seeds essential oil bound effectively with the targeted protein with the docking score of -6.14 kcal mol−1. Overall, our combined experimental and computational study provides scientific justification for the use of fenugreek leaves essential oil as a natural antifungal agent against R. solani. Moreover, fenugreek leaves essential oil being most effective against D. oryzae may also be used as a natural antifungal agent against it.

Alginate Based Aloe Vera Gel And/Or Pomegranate Seed Essential Oil Added Edible Coating Film Production Using Casting Method To Extend Strawberries and Cherries Shelf Life

Many type of material used, for coating food to extend shelf life and that may be eaten together with the coated food. Today, environmentally friendly technologies, like edible films produced from biodegradable materials, are preferred in food coating. In this study alginate-based (3g) aloe vera gel (1.5g) and/or pomegranate seed essential oil (1%) added plasticized with glycerol (2g) edible films were produced by casting method for use in food coating at 5 different composition. Aloe vera gel and pomegranate seed essential oil (3%) added edible composite films have the lowest (72.56%) water solubility value. Pomegranate seed essential oil added edible films have lower water vapor transmission rate (0,0897*10-3), and lower moisture content (19.95%) values. 1% pomegranate seed essential oil added film has the lowest film thickness (0.125 mm). FTIR spectra of the films confirmed the interactions between alginate, aloe vera gel and pomegranate seed essential oil thus proving that the films were prepared successfully. Strawberries and cherries were coated with produced edible coating films and weight loss and color analysis were carried out to observe coating performance. It was seen that alginate based and pomegranate seed essential oil added edible coatings reducing moisture loss, color change and surface deformation of strawberries and cherries. The biggest difference of this study from previous studies is that pomegranate seed essential oil was used for the first time in this study, for edible coating film production and the results were quite successful especially for the cherry’s coating.

Defense Mechanisms Induced by Celery Seed Essential Oil against Powdery Mildew Incited by Podosphaera fusca in Cucumber.

This study aimed to evaluate the effectiveness of essential oil extracted from celery (Apium graveolens) seeds (CSEO) for the control of powdery mildew of cucumber (Cucumis sativus) incited by Podosphaera fusca and to investigate the metabolic and genetic defense mechanisms triggered by the treatment with this essential oil in cucumber seedlings. The main compounds in the CSEO as determined by gas chromatography-mass spectrometry (GC-MS) analysis were d-limonene, 3-butyl phthalide, β-selinene, and mandelic acid. The treatment with CSEO led to an increase in the content of both chlorophyll and phenolic/flavonoid compounds in cucumber leaves. In greenhouse tests, the application of CSEO reduced by 60% the disease severity on leaves of cucumber plants and stimulated the activity of defense-related enzymes such as β-1,3-glucanase, chitinase, phenylalanine ammonia-lyase, peroxidase, and polyphenol oxidase. Moreover, treatment with CSEO induced overexpression of β-1,3-glucanase, chitinase, and phenylalanine ammonia-lyase genes. A highly significant correlation was found between the β-1,3-glucanase, chitinase, and phenylalanine ammonia-lyase enzymatic activities and the relative expression of the corresponding encoding genes in both inoculated and non-inoculated cucumber seedlings treated with the essential oil. Overall, this study showed that CSEO is a promising eco-friendly candidate fungicide that can be exploited to control cucumber powdery mildew.

Black cumin essential oil as a valuable source of bioactive compounds: Evaluation of the conventional vs. modern extraction technique

Within this investigation, the effect of conventional and sophisticated extraction method was evaluated on the chemical composition of black cumin seeds (Nigella sativa L.) essential oils and their bioactive characteristics. Soxhlet extraction at 60 °C by hexane (SEH) and petroleum ether (SEP) was adopted as traditionally used technique, while the supercritical extraction with CO2 (SFE), under the pressure of 10 MPa and temperature of 40 °C, was performed as a modern method, expected to overcome the drawbacks of the conventional solvent extraction.The results showed that SFE enabled up to ten times higher extraction yields, compared to essential oils derived after Soxhlet extraction, however, the bioactive compounds content, such as polyphenols, flavonoids and carotenoids, were extracted in higher quantities in the oil from Soxhlet extraction performance. Thereby, the strongest antioxidant agent was found to be the essential oil obtained from SEP, followed by the oil from SFE and oil obtained from SEH, respectively. The GC-MS analysis revealed that the content of thymoquinone was the highest in the essential oil from SEP (69.58%), and the obtained values are among the highest reported within the available literature data. Also, this oil sample contained about eleven times higher thymoquinone quantities than the essential oil obtained by SFE, which was mostly constituted of a methyl linoleate, a fatty acid methyl ester of linoleic acid. In addition, the essential oil from SEP exerted a value added antimicrobial properties, where it was found to be particularly effective in suppression of the Gram-positive bacteria growth.

Hydrodistillation and Steam Distillation of Fennel Seeds Essential Oil: Parameter Optimization and Application of Cryomilling Pretreatment

The aim of this study was to examine the effectiveness of cryomilling (CM) pretreatment on the isolation of fennel seeds essential oil (EO). Therefore, the study included (i) the process optimization and comparison of the efficiencies of hydrodistillation (HD) and steam distillation (SD); (ii) the evaluation of the effect of the CM application prior to the distillation method (selected based on the results obtained in the first part) on the EO yield; (iii) the evaluation of possible quality differences of the EOs obtained with the performed isolation methods. The obtained results showed that HD (at a solid to liquid ratio 1:10 and a distillation time of 120 min) was more efficient in terms of the EO yield compared to SD (at a pressure of 0.83 bar and distillation time of 117 min as optimal conditions). Moreover, an increased EO yield or even reduced distillation time was observed when HD was combined with a 3 min or 5 min CM pretreatment. GC-MS analysis showed no qualitative differences in chemical composition upon any of the applied isolation procedures, although higher amounts of volatiles were found in the cryomilled samples. The results of this study could be of interest to academia and the EO industry, as CM showed a positive aspect in EO isolation that could provide economic benefits in terms of higher yields or energy savings.

Assessment of anticancer, antimicrobial, antidiabetic, anti-obesity and antioxidant activity of Ocimum Basilicum seeds essential oil from Palestine

BackgroundMany modern pharmaceutical researchers continue to focus on the discovery and evaluation of natural compounds for possible therapies for obesity, diabetes, infections, cancer, and oxidative stress. Extraction of Ocimum basilicum seed essential oil and evaluation of its antioxidant, anti-obesity, antidiabetic, antibacterial, and cytotoxic activities were the goals of the current study.MethodO. basilicum seed essential oil was extracted and evaluated for its anticancer, antimicrobial, antioxidant, anti-obesity, and anti-diabetic properties utilizing standard biomedical assays.ResultsO. basilicum seed essential oil showed good anticancer activity against Hep3B (IC50 56.23 ± 1.32 µg/ml) and MCF-7 (80.35 ± 1.17 µg/ml) when compared with the positive control, Doxorubicin. In addition, the essential oil showed potent antibacterial (against Klebsiella pneumoniae, Escherichia coli, Staphylococcus aureus, Proteus mirabilis, and Pseudomonas aeruginosa) and antifungal (against Candida albicans) activities. Moreover, as for the anti-amylase test, IC50 was 74.13 ± 1.1 µg/ml, a potent effect compared with the IC50 of acarbose, which was 28.10 ± 0.7 µg/ml. On the other hand, for the anti-lipase test, the IC50 was 112.20 ± 0.7 µg/ml a moderate effect compared with the IC50 of orlistat, which was 12.30 ± 0.8 µg/ml. Finally, the oil had a potent antioxidant effect with an IC50 of 23.44 ± 0.9 µg/ml compared with trolox (IC50 was 2.7 ± 0.5 µg/ml).ConclusionThis study has provided initial data that supports the importance of O. basilcum essential oil in traditional medicine. The extracted oil not only exhibited significant anticancer, antimicrobial, and antioxidant properties but also antidiabetic and anti-obesity effects, which provided a foundation for future research.

A Comprehensive Analysis of Cinnamon, Flaxseed, and Lemon Seed Essential Oils’ Effects on In Vitro Gas Formation and Nutrient Degradability in Diets

This study aimed to assess the impact of essential oils (EOs) on in vitro gas formation and the degradability of dairy and beef cattle diets. This study also aimed to investigate the effects of different types of EOs on nutrient utilization and rumen microbial activity. The current study was conducted using a fully randomized design consisting of eight experimental treatments, including two control treatments without any additives, and treatments with cinnamon essential oil (CEO), flaxseed essential oil (FEO), and lemon seed essential oil (LEO) at a concentration of 60 mg/kg fresh mass. Two control treatments were used, one with alfalfa silage and dairy concentrate (DC, CON-DC) and the other with alfalfa silage and fattening concentrate (FC, CON-FC). Gas formation, dry matter (DM) digestibility, crude protein (CP) digestibility, effective degradability (ED), and soluble fractions of DM and organic matter (OM) were evaluated. CEO had a substantial effect on gas formation (p &lt; 0.05). When EOs were added to the diets, they increased dry matter digestibility after 24 h of incubation as compared to control treatments. After 24 h of incubation, FCCEO and FCFEO had the highest CP digestibility among the diets. FCLEO considerably enhanced ED, as well as the soluble fraction of DM (a) at a passage rate of 2% per hour. Treatment with FCCEO resulted in a significant increase in soluble fractions compared to the control diets. At a passage rate of 2% h, DCCEO had the maximum ED value. When EOs were introduced to the diet, they dramatically decreased the insoluble portion of CP (b). Compared to the control treatments, gas production was significantly lower in the presence of LEO (FCLEO; p &lt; 0.05). The addition of EOs to cattle diets may increase nutrient utilization and enhance rumen microbial activity. EOs extracted from lemon seeds (at a dose of 60 mg/kg of diet) lowered gas production in both dairy cattle and fattening diets.

Using pulsed electric field pre-treatment to optimize coriander seeds essential oil extraction and evaluate antimicrobial properties, antioxidant activity, and essential oil compositions

In this study, a pulse electric field was used as a pre-treatment to extract essential oil (EO) from coriander seeds. Three voltage levels of 0.25, 1, and 1.75 kV/cm and three levels of pulse numbers 10, 55, and 100 were used and the extraction conditions were optimized. EO extraction efficiency, phenolic content, antioxidant activity, oxidative stability of oil treated with coriander seeds EO, and microbial activity were measured. Optimal conditions were obtained at 1 kV/cm and 55 pulses. The best results were obtained at the optimal point, which included the EO extraction efficiency of 0.39 g/100 g, the total phenolic content of 0.199 mg GAE/100 g, the antioxidant activity of 20.732 mg/ml, and the oxidative stability of 5.98 h. Linalool (61.9%) was the most common constituent of coriander seeds EO. According to SEM results, the inhibitory effect of coriander seeds EO was on the bacterial cell wall.

Synthesis of tetraalkoxyaryldihydrobenzo[g]indazoles from metabolites of dill and parsley seeds essential oil

An efficient method for the conversion of available plant allylpolyalkoxybenzenes into unsubstituted and arylsubstituted polymethoxylated aryldihydrobenzo[g]indazoles, analogues of combretastatin A4, has been developed. The selective demethylation of target compounds resulted in indazoles with different position of OH-group. Their structure was confirmed by X-ray analysis. A sea urchin embryo assay revealed the lack of tubulin-related antimitotic activity of aryldihydrobenzo[g]indazoles with systemic toxicity of a compound featuring OH group and 1-unsubstituted pyrazole ring.

Evaluation of the Antioxidant Properties of Carvacrol as a Prospective Replacement for Crude Essential Oils and Synthetic Antioxidants in Food Storage.

The phenolic structural analogues of synthetic antioxidants such as butylated hydroxytoluene (BHT) in essential oils have been reported to exhibit antioxidant properties. Additionally, their lipophilicity makes them suitable for use in lipid-rich foods. This study evaluated the antioxidant capacity of carvacrol, a monoterpenoid antioxidant compound in the Monodora myristica (Gaertn.) seed essential oil, compared to the seed essential oil and BHT. In vitro studies (ferric reducing antioxidant power (FRAP), metal chelating activity (MCA), and nitric oxide scavenging activity (NOSA)) were conducted to ascertain if the antioxidant capacity of carvacrol was comparable to that of the seed essential oil. The potential binding affinity and molecular interactions between carvacrol and lipoxygenase (LOX) and its homologous model were investigated in silico. The molecular docking was performed using Autodock Vina, and the best poses were subjected to molecular dynamics simulation. The IC50 for MCA and NOSA were: carvacrol 50.29 µL/mL, seed essential oil (SEO) 71.06 µL/mL; and carvacrol 127.61 µL/mL, SEO 165.18 µL/mL, respectively. The LOX model was Ramachandran favoured (97.75%) and the overall quality factor in the ERRAT plot was 95.392. The results of the molecular docking and molecular dynamics simulations revealed that lipoxygenase has a higher affinity (-22.79 kcal/mol) for carvacrol compared to BHT. In the LOX-BHT and LOX-carvacrol complexes, the root-mean-square deviation (RMSD), root-mean-square fluctuation (RMSF), and the radius of gyration (RoG) were not significantly different, indicating similar molecular interactions. The results obtained from this study suggest that carvacrol exhibits an antioxidant capacity that may be explored as an alternative for crude essential oils and synthetic compounds during the storage of lipid-rich foods.

Chemical Composition and Insecticidal Activity against Tribolium Castaneum of Thapsia garganica L. Seed Essential Oil.

Due to the several side effects of synthetic pesticides, including environmental pollution, threats to human health, and the development of pest resistance to insecticides, the use of alternative healthy, available and efficient agents in pest management strategies is necessary. Recently, the use of essential oil obtained from aromatic plants has shown significant potential for insect pest management. For this reason, the essential oil isolated from seeds of Thapsia garganica L. was investigated for the first time for its chemical profile, and its toxicity and repellency effects against Tribolium castaneum adults. Qualitative and quantitative analyses of the chemical composition by gas chromatography coupled to mass spectrometry (GC/MS) revealed the presence of 18 organic volatiles representing 96.8 % of the total constituents. The main compounds were 1,4-dimethylazulene (51.3 %) followed by methyl palmitate (8.2 %), methyl linoleate (6.2 %) and costol (5.1 %). Concerning the repellent effect, results revealed that SEO (Seed Essential Oil) was very repellent towards T. castaneum adults, with 100 % repellency after 2 h of exposure. Furthermore, the essential oil exhibited remarkable contact toxicity against T. castaneum (93.3 % of mortality) at the concentration of 10 % (v/v). The median lethal dose (LD50 ) of the topical application of the seed essential oil was 4.4 %. These encouraging outcomes suggested that the essential oil from T. garganica seeds could be considered a potent natural alternative to residual persistent and toxic insecticides.

Enhancing Yields and Antioxidant Activities of Caraway Seeds Essential Oil by Ultrasonic Treatment Combined with Hydro-distillation, and Microwave-assisted Hydro-distillation

This study examined the effects of ultrasonic treatment on the amount and quality of essential oils extracted from caraway seeds using ultrasonic treatment followed by hydro-distillation and ultrasonic treatment followed by microwave-assisted hydro-distillation. Afterward, the obtained results were compared with those of untreated extracts issued from conventional hydro-distillation and microwave-assisted hydro-distillation. The essential oil yields ranged from 1.18 ± 0.09 to 1.36 ± 0.09% w/w, depending on the extraction technique. Analysis by gas chromatography coupled with mass spectrometry showed the presence of 21 compounds in all the extracts. Produced essential oils consisted of 9.65 ± 1.742 % to 18.59 ± 1.377 % monoterpenes hydrocarbons and 77.20 ± 2.847 to 84.60 ± 1.909 % oxygenated monoterpenes. The main components were limonene and carvone, but the amounts of each component depend on the methods. Additionally, the antioxidant activity of caraway seeds essential oils was determined using the DPPH (2,2-diphenyl-1-picrylhydrazyl) assay. The antioxidant ability of the examined oils was moderate, and the USMAHD oil median inhibitory concentration (IC50) value was the lowest. Moreover, a statistical investigation paved the way for a possible correlation between the carvone/limonene ratio and IC50. Consequently, this aspect, which is the potential for improving the extract’s quality by modifying the ratio of the target components known for their high antioxidant effects, made this study novel.

Optimization of microwave-assisted hydrodistillation of essential oils from fennel seeds

Fennel seeds are a medicinal plant in species Foeniculum vulgare. Essential oils are commonly used for flavoring or in the cosmetic industry and also have antibacterial properties. The purpose of this research was to increase the yield of essential oils by studying the optimize conditions for microwave-assisted hydrodistillation of essential oils from fennel seeds using response surface methodology in combination with central composite design (CCD). The factors used in this study consisted of extraction time (60–120 min), microwave power (300–500 W), and solid–liquid ratio (1:10–1:20 g/mL). The experimental data obtained were fitted to quadratic equation due to high coefficient of determination (R2 = 0.9624). It was found that the microwave power factor and the square factor of microwave power were significant (p < 0.05) for the percentage yield of fennel seeds essential oil. The predicted conditions for extraction were time 96.36 min, microwave power 400 W and solid to liquid ratio 1:14.85 g/mL. The predicted percentage yield was 0.94. The actual yield percentage of essential oils was 0.98. In addition, GC–MS analysis revealed that major components of fennel seeds were anethole (46.12 %) and estragole (36.39 %). The compounds were classified in the group of phenylpropanoid compounds 83.47 %, oxygenated monoterpene 10.62 %, monoterpene 4.81 %, sesquiterpene 0.06 % and ester 0.04 %. Due to its shorter duration and higher yield, MAHD is a good alternative to extracting essential oils from fennel seeds.

Elemental composition, total fatty acids, soluble sugar content and essential oils of flowers and leaves of Moringa oleifera cultivated in Southern Portugal

The evaluation of the elemental content of moringa leaves and flowers by Energy Dispersive X-Ray Fluorescence Spectrometry revealed that the leaves are a good source of some macro (Ca and K) and micronutrients (Mn) beyond the presence of important polyunsaturated fatty acids (PUFAs), essential in human nutrition. Total soluble sugars prevail in the flowers which may be linked to insect attraction and the pollination process. M. oleifera leaves, flowers and seeds essential oils (EOs) were isolated by hydrodistillation. Gas chromatography and gas chromatography-mass spectrometry analysis (GC-MS) showed EOs dominated by alkanes and fatty acids in diverse ratios in the analyzed plant parts. The nutritional characterization of M. oleifera cultivated in Portugal showed some important nutrients to human physiology. Further studies will allow determining if its consumption may overcome the nutritional imbalances of daily modern households, preventing the emergence of hypertension and diabetes.

Azotobacter chroococcum inoculation under low drought stress condition improves Trachyspermum ammi seeds' essential oil bioactivity

Trachyspermum ammi seed is an important spice and aromatic herb due to its bioactive essential oil. Drought stress and Azotobacter chroococcum have also been reported to improve medicinally important biomolecules and secondary metabolite content in plants. The present study was undertaken to determine the ability of A. chroococcum in combination with drought stress to improve the anticancer potential of T. ammi seed essential oil. The overall results indicated that several compounds in T. ammi seeds essential oil increased following A. chroococcum bacteria treatment under slight drought stress (irrigation at 80% field capacity), thus improving the antiradical efficacy. Furthermore, the application of A. chroococcum as plant growth promoting agent together with slight drought stress significantly (p < 0.05) resulted in a remarkable decrease in tumor size, diminish the liver enzymes activities and lipid peroxidation potential in mice inoculated with TUBO cell line (breast cancer cell). The up-regulated caspase-3 gene expression also confirms the results as well. Our finding revealed that slight drought stress (irrigation at 80% field capacity) together with treatment of T. ammi plant with A. chroococcum bacteria could be a promising approach to improving the pharmaceutical properties of T. ammi seeds' essential oil.