Volatile Compounds Of Essential Oils Research Articles

Bridging the Gap: Harnessing Plant Bioactive Molecules to Target Gut Microbiome Dysfunctions in Amyotrophic Lateral Sclerosis.

The correlation between neurodegenerative diseases and the gut microbiome is increasingly evident, with amyotrophic lateral sclerosis (ALS) being particularly notable for its severity and lack of therapeutic options. The gut microbiota, implicated in the pathogenesis and development of ALS, plays a crucial role in the disease. Bioactive plant molecules, specifically volatile compounds in essential oils, offer a promising therapeutic avenue due to their anti-inflammatory properties and gut-modulating effects. Our narrative review aimed to identify microbiota-associated bacteria in ALS and analyze the benefits of administering bioactive plant molecules as much-needed therapeutic options in the management of this disease. A comprehensive search of PubMed database articles published before December 2023, encompassing research on cell, human, and animal ALS models, was conducted. After selecting, analyzing, and discussing key articles, bacteria linked to ALS pathogenesis and physiopathology were identified. Notably, positively highlighted bacteria included Akkermansia muciniphila (Verrucomicrobia phylum), Faecalibacterium prausnitzii, and Butyrivibrio spp. (Firmicutes phylum). Conversely, members of the Escherichia coli spp. (Proteobacteria phylum) and Ruminococcus spp. (Firmicutes phylum) stood out negatively in respect to ALS development. These bacteria were associated with molecular changes linked to ALS pathogenesis and evolution. Bioactive plant molecules can be directly associated with improvements in the microbiome, due to their role in reducing inflammation and oxidative stress, emerging as one of the most promising natural agents for enriching present-day ALS treatments.

Screening of volatile compounds of essential oils with acaricidal activity in Rhipicephalus microplus larvae using a new in vitro evaluation method

ABSTRACT The study assessed the acaricidal properties of 20 compounds derived from essential oils against the Rhipicephalus microplus tick, a significant menace to tropical livestock with considerable economic losses. A novel methodology was devised, involving the determination of mortality times for R. microplus larvae upon direct contact with these compounds. Mortality times were compared against a negative control (soybean oil) and two positive controls (commercial pour-on products). Tests were conducted in 48-well polyethylene plates, with around 100 larvae immersed in 200 µl of oil (at a 100% dose). The 10 compounds exhibiting the shortest mortality times were subsequently diluted in soybean oil at varying concentrations. Notably, thymol exhibited potent acaricidal activity, with the lowest effective dose (1.56%) resulting in larval mortality within 15 minutes, whereas positive controls necessitated over 66 minutes. A correlation was established between the molecular structure of the compounds and their acaricidal efficacy, indicating that cyclic compounds containing 10 carbon atoms demonstrated heightened lethality compared to acyclic counterparts. This innovative methodology enables the rapid identification of substances with substantial acaricidal potential in vitro, yielding results within minutes, in stark contrast to the traditional larval immersion test, which demands a minimum of 24 hours for conclusive outcomes.

Antifungal effects of carvacrol, the main volatile compound in Origanum vulgare L. essential oil, against Aspergillus flavus in postharvest wheat

Plant volatile organic compounds (VOCs) with antimicrobial activity could potentially be extremely useful fumigants to prevent and control the fungal decay of agricultural products postharvest. In this study, antifungal effects of volatile compounds in essential oils extracted from Origanum vulgare L. against Aspergillus flavus growth were investigated using transcriptomic and biochemical analyses. Carvacrol was identified as the major volatile constituent of the Origanum vulgare L. essential oil, accounting for 66.01 % of the total content. The minimum inhibitory concentrations of carvacrol were 0.071 and 0.18 μL/mL in gas-phase fumigation and liquid contact, respectively. Fumigation with 0.60 μL/mL of carvacrol could completely inhibit A. flavus proliferation in wheat grains with 20 % moisture, showing its potential as a biofumigant. Scanning electron microscopy revealed that carvacrol treatment caused morphological deformation of A. flavus mycelia, and the resulting increased electrolyte leakage indicates damage to the plasma membrane. Confocal laser scanning microscopy confirmed that the carvacrol treatment caused a decrease in mitochondrial membrane potential, reactive oxygen species accumulation, and DNA damage. Transcriptome analysis revealed that differentially expressed genes were mainly associated with fatty acid degradation, autophagy, peroxisomes, the tricarboxylic acid cycle, oxidative phosphorylation, and DNA replication in A. flavus mycelia exposed to carvacrol. Biochemical analyses of hydrogen peroxide and superoxide anion content, and catalase, superoxide dismutase, and glutathione S-transferase activities showed that carvacrol induced oxidative stress in A. flavus, which agreed with the transcriptome results. In summary, this study provides an experimental basis for the use of carvacrol as a promising biofumigant for the prevention of A. flavus contamination during postharvest grain storage.

Antiviral Molecular Targets of Essential Oils against SARS-CoV-2: A Systematic Review

Essential oils are potential therapeutics for coronavirus disease 2019 (COVID-19), in which some of the volatile compounds of essential oils have been well known for their broad antiviral activities. These therapeutic candidates have been shown to regulate the excessive secretion of pro-inflammatory cytokines, which underlies the pathogenesis of severe COVID-19. We aimed to identify molecular targets of essential oils in disrupting the cell entry and replication of SARS-CoV-2, hence being active as antivirals. Literature searches were performed on PubMed, Scopus, Scillit, and CaPlus/SciFinder (7 December 2022) with a truncated title implying the anti-SARS-CoV-2 activity of essential oil. Data were collected from the eligible studies and described narratively. Quality appraisal was performed on the included studies. A total of eight studies were included in this review; four of which used enzyme inhibition assay, one—pseudo-SARS-CoV-2 culture; two—whole SARS-CoV-2 culture; and one—ACE2-expressing cancer cells. Essential oils may prevent the SARS-CoV-2 infection by targeting its receptors on the cells (ACE2 and TMPRSS2). Menthol, 1,8-cineole, and camphor are among the volatile compounds which serve as potential ACE2 blockers. β-caryophyllene may selectively target the SARS-CoV-2 spike protein and inhibit viral entry. Other interactions with SARS-CoV-2 proteases and RdRp are observed based on molecular docking. In conclusion, essential oils could target proteins related to the SARS-CoV-2 entry and replication. Further studies with improved and uniform study designs should be carried out to optimize essential oils as COVID-19 therapies.

Microencapsulation of marjoram essential oil as a food additive using sodium alginate and whey protein isolate

Encapsulation techniques are generally used to preserve the volatile compounds of essential oils. This study aimed to evaluate the influence of process variables on the microencapsulation of marjoram essential oil (MEO) (Origanum majorana L.) by ionic gelation. The effect of sodium alginate concentration (0.5–2 g/100 mL), emulsifier concentration (0.5–2 g/100 mL whey protein isolate (WPI)), and cationic bath concentration (0.05–0.3 mol/L CaCl2) on the emulsions and beads properties were investigated, according to a rotatable central composite design. MEO chemical composition and antimicrobial activity were assessed. Emulsions were characterized for droplet size and viscosity, while the particles were analyzed for encapsulation efficiency, size and circularity, and morphology. High concentrations of alginate and WPI intensified the porous structure of the beads, reducing droplet mean diameter and encapsulation efficiency. High alginate concentrations also increased emulsion viscosity, affecting positively beads' circularity. The intermediate concentration of sodium alginate (1.25 g/100 mL), WPI (1.25 g/100 mL), and CaCl2 (0.175 mol/L) were selected as the most appropriate conditions to produce beads with satisfactory circularity and high encapsulation efficiency.

Profile Volatile Compounds in Essential Oils on Different Parts of Cardamom with Antioxidant Activity

Amomum compactum Soland Ex. Maton from the Zingiberaceae, known as Java cardamom in Indonesia, is a valuable medicinal plant because of its bioactivity. This study aims to identify and evaluate the bioactive compounds and antioxidant activity of Java cardamom parts (leaves, stems, rhizomes, fruits (pods and seeds)) to explore their bioactivity values. GC-MS analysis was used to identify the bioactive compounds of Java cardamom parts in essential oils. Antioxidant activity was carried out by two methods: DPPH and FRAP. GC-MS analysis of four parts of the Java cardamom obtained 47 compounds as monoterpenes (33), sesquiterpenes (9), hydrocarbons (1), fatty alcohols (1), fatty acids (1), fatty acid esters (1), and diterpenoids (1). 1.8-Cineol is the most dominant secondary metabolite and is found in every part of Java cardamom essential oil, with the highest content produced in Java cardamom steam essential oil (50.78%), followed by Java cardamom fruits essential oil (45.59%). Furthermore, the activity of DPPH and FRAP ranged from 19.07 (leaves) – 27.38 (stems) and 93.43 (stems) – 115.99 (fruits) mol TEAC/g FW. The maximum antioxidant activity is produced in Java cardamom fruit essential oil. Thus, it can be used as a source of producing metabolites as antioxidants in the pharmaceutical industry.

Chemical Composition of Essential Oil from the Zingiber monophyllum (Zingiberaceae) from Vietnam

This research aimed to identify the volatile compounds of essential oils found in the rhizomes and leaves of Zingiber monophyllum Gagnep. This is the first phytochemical investigation of this species. Essential oils from the rhizomes and leaves of Z. monophyllum were obtained by hydrodistillation and analyzed by gas chromatography coupled with mass spectrometry (GC/MS). Twenty-three compounds accounting for 90.9% of the rhizome oils were identified, while there were seventeen volatile components corresponding to 91.8% in the leaf oil. The major constituents of rhizome and leaf oils were β-pinene (44.9% and 29.8%), borneol (5.2% and 3.1%), α-pinene (4.1% and 1.8%), and myrtenal (3.2% and 4.0%). However, larger amounts of dihydroedulan I (21.7%), n-hexadecanol (7.0%), and α-copaene (6.5%) were found in the leaf oil only.

Chemical Constituents, Antioxidant, Anti-Tyrosinase, Cytotoxicity, and Anti-Melanogenesis Activities of Etlingera elatior (Jack) Leaf Essential Oils

Essential oils of plants have been used widely in cosmetic preparations. Being both perfuming and active ingredients, the functions of essential oils mean they are high-value ingredients. In this study, the leaf of Etlingera elatior (Jack) or Torch ginger was used. The essential oils (EO) were prepared by conventional hydrodistillation (HD) and microwave-assisted hydrodistillation (MAHD). The volatile compounds of EOs were analyzed by gas chromatography spectroscopy (GC-MS). The antioxidant activities by means of DPPH radical scavenging and ferric-reducing antioxidant power (FRAP) were determined. The inhibition of tyrosinase activity was investigated. The cytotoxicity was performed against human fibroblast cell lines (NIH/3T3) and melanoma cell lines (A375 and B16F10). The decreasing melanin content was measured in melanoma cell lines. The resulting essential oils were detected for 41 compounds from HD extraction dominants by terpenes, namely sesquiterpenes (48.499%) and monoterpenes (19.419%), while 26 compounds were detected from MAHD with the fatty alcohols as the major group. The higher antioxidant activities were found in HD EO (IC50 of 16.25 ± 0.09 mg/mL from DPPH assay and 0.91 ± 0.01 mg TEAC/g extract from FRAP assay). The survival of normal fibroblast cell lines remained at 90% at 500 µg/mL HD EO, where the EO possessed the half-maximal toxicity dose (TD50) of 214.85 ± 4.647 and 241.128 ± 2.134 μg/mL on B16F10 and A375 cell lines, respectively. This could suggest that the EO is highly selective against the melanoma cell lines. The melanin content was decreased at the half-maximum efficacy (IC50) at 252.12 ± 3.02 and 253.56 ± 3.65 in the A375 and B1610 cell lines, respectively, which were approximately 2.8-fold lower than kojic acid, the standard compound. The results of this study evidence the use of Etlingera elatior (Jack) leaf as a source of essential oil as an active agent in cosmetics.

Comparison of Volatile Compounds from Clary Sage (Salvia sclarea L.) Verticillasters Essential Oil and Hydrolate

The volatile compounds of essential oil (EO) and corresponding hydrolate (HY) extracted by steam distillation from clary sage (Salvia sclarea L.) cv “Domaća mirisna” grown in Serbia were identified using gas chromatography/mass spectrometry (GC/MS). The most abundant compounds of EO were linalyl acetate (43.5%) and linalool (25.9%), followed by α-terpineol, germacrene D, and geranyl acetate. In the corresponding HY (recovered water-soluble fraction of EO) the dominant were linalool (63.3%) and α-terpineol (26.8%), followed by geraniol. These differences in composition between clary sage EO and HY could be explained by linalyl acetate's low water solubility. Clustering of 55 clary sage EO accessions (from literature) shows the presence of several chemotypes: linalyl acetate+linalool, linalyl acetate+sclareol, linalool+geranyl acetate, germacrene D+β-caryophyllene, caryophyllene oxide, and three unspecified chemotypes (geranyl acetate, methyl chavicol, and α-terpineol). According to this classification, clary sage cv “Domaća mirisna” belongs to a moderate linalyl acetate chemotype (between 19.8 and 45.7%). Further investigations need to focus on clary sage HY and their potential applications because HYs could increase economic gain as a by-product. However, their utilization for other purposes (cosmetic, postharvest fruit processing, organic agriculture, etc.) could be a safe solution for wastewater produced during EO distillation.

In Vitro Antimalarial Activity and Phytochemical Analysis of Aerial Parts of Artemisia fragrans Willd.

Background: Malaria is one of the most momentous transmittable diseases globally. Medicinal herbs like Artemisia species might be possible sources of new, effective, and cheap antiplasmodial products, making up the leading molecules to investigate new antimalarial drugs. The Artemisia genus, which belongs to the Asteraceae family, is a widely distributed medicinal plant in Iran. Methods: In this study, the antimalarial activities of essential oil, different extracts, and vacuum liquid chromatography (VLC) fractions of A. fragrans Willd. were examined by a cell-free β-hematin formation assay. The aerial parts of A. fragrans were extracted by a Soxhlet extractor, and essential oil was obtained by a Clevenger apparatus. Then, GC-MS analysis was used to identify volatile compounds of essential oil and the 100% VLC fraction of chloroform. Results: Among the extracts, chloroform extract illustrated considerable antimalarial activity compared to the control (P < 0.001), with the IC50 value of 1.22 ± 0.05 mg/mL. Among the fractions, 100% VLC fraction of chloroform extract illustrated potent antimalarial effects compared to the control (P < 0.001). The volatile oil demonstrated moderate antimalarial effects (P < 0.001) compared with the control. Besides, GC-MS determined that sesquiterpenes in the 100% ethyl acetate fraction of the chloroform extract and oxygenated monoterpenes in the essential oil might be responsible for the potent antimalarial activity of this plant. Conclusions: The 100% ethyl acetate fraction of chloroform extract along with the essential oil of A. fragrans indicated potent and moderate activity, possibly due to sesquiterpenes and oxygenated monoterpenes, respectively.

Rock Samphire, a Candidate Crop for Saline Agriculture: Cropping Practices, Chemical Composition and Health Effects

The recent market trends for functional healthy foods have rekindled the interest in wild edible species and created a market niche for high added value products. The current supply, mainly supported by plants collected from the wild, cannot meet increasing market needs; therefore, it is of major importance to establish cropping protocols and further valorize wild plants for culinary and industrial applications. Sea fennel is a wild edible halophyte that is an important ingredient in local cuisines and is also used in folk medicine for its beneficial health effects. Its valorization has not been commercially explored on a great scale and more efforts are needed to integrate the species in farming systems. The present review compiles the most recent reports regarding the farming practices that could allow for the establishment of cultivation protocols for farmers, while the main constraints that hinder the further exploitation of the species are also presented. Moreover, this review presents the most up-to-date information regarding the chemical composition (e.g., chemical composition of the aerial parts and volatile compounds in essential oils) and the health-related effects of various plant parts (e.g., antimicrobial, insecticidal and anticholinesterase activities) aiming to reveal possible alternative uses that will increase the added value of the species and will contribute to its commercial exploitation. Finally, the future remarks and the guidelines that have to be followed are also discussed.

Phytochemical analysis and anticancer activity of Falcaria vulgaris Bernh growing in Moghan plain, northwest of Iran

BackgroundFalcaria vulgaris Bernh among the most important member of Apiaceae family has been used for medical investigation in Iran and some regions in the world. This plant possesses a range of coumarin and flavonoids compounds that have many therapeutic properties such as gastrointestinal and liver diseases, skin ulcers, gastric ulcers, and intestinal inflammation. It has also been found that these compounds lead to cytotoxic effects.ObjectiveThis study contains concentrates on the cytotoxic effect and induction of apoptosis on cancerous cells (SW-872) through various extracts and essential oil of Falcaria vulgaris Bernh. It considers the volatile compounds of effective samples.MethodsThe shoot of the plant was extracted by the Soxhlet apparatus and its essential oil was taken by the Clevenger apparatus. The cytotoxicity of the samples was evaluated by the MTT method and the mechanism of cancer cell death by flow cytometry and finally, the volatile compounds of essential oils and effective extracts were identified by GC-MS.ResultsThe results demonstrated that n-Hexane extract and 40% VLC fraction had the greatest cytotoxic effect on SW-872 cells. While, the most abundant volatile compounds in essential oil and 40% VLC fraction of n-Hexane extract were terpenoid compounds like (+) spathulenol and caryophyllene oxide, in n-Hexane extract tetradecan, and spathulenol were the most, respectively.ConclusionThe fraction of 40% n-Hexane was in a concentration-dependent manner and significantly with controlling cells inhibited the growth of cancer cells. A plausible explanation could be made to account for this effect. This inhibition was made through induction of apoptosis and due to the presence of effective volatile compounds such as terpenoids and non-terpenoids which could be considered as valuable natural sources for the isolation of anti-cancer compounds.

Free Volatile Compounds of Veronica austriaca ssp. jacquinii (Baumg.) Eb. Fisch. and Their Biological Activity.

The composition of free volatile compounds of essential oils (EO) and hydrosols (Hy) from four different localities of the species Veronica austriaca ssp. jacquinii (Baumg.) Eb. Fisch. were analyzed by gas chromatography coupled with mass spectrometry. In the EOs, the most abundant compounds identified were hexahydrofarnesyl acetone (23.34–52.56%), hexadecanoic acid (palmitic acid, 26.71–58.91%) and octadecanol acetate (0–6.24%). The hydrosols were characterized by high abundance of methyl eugenol (23.35–57.93%), trans-p-mentha-1(7),8-dien-2-ol (5.24–7.69%) and thymol (3.48–9.45%). Glandular trichomes were analyzed using SEM (Scanning Electron Microscopy), as they are the sites of synthesis of free volatile compounds. We have detected glandular trichomes, consisting of a one stalk cell and two elliptically shaped head cells, and non-glandular (unbranched, bi-cellular to multicellular) trichomes on stems, leaves and the sepals. Data for volatile compounds from EOs and hydrosols were analyzed using Principal Component Analyses (PCA) to demonstrate variations in the composition of the volatile compounds identified. Isolated samples of EO and hydrosols were analyzed for their antioxidant activity using two methods, DPPH (2,2-diphenyl-1-picrylhydrazyl) and ORAC (Oxygen Radical Absorbance Capacity). The essential oils showed higher antioxidant activity than the hydrosols in ORAC method, but lower activity by the DPPH method. The isolates were also tested for their antiproliferative activity on different types of cancer cells and also on two lines of healthy cells, and the results showed that the extracts were not toxic to the cell lines tested. Total polyphenols, total tannins, total flavonoids and total phenolic acids were also analyzed and determined spectrophotometrically. The free volatile compounds of Veronica austriaca ssp. jacquinii can be considered as a safe natural product.

Variation in aroma level of holy basil (Ocimum tenuiflorum L.) leaves is related to volatile composition, but not trichome characteristics

Holy basil or tulsi (Ocimum tenuiflorum L.) is an herb with a unique aroma in culinary uses. The aroma comes from volatile compounds in essential oils produced and stored in glandular trichomes. Different glandular trichome characteristics affect essential oil yield. Essential oil compositions and aroma levels vary among holy basil genotypes. However, relationships between aroma levels and trichome characteristics, as well as between aroma levels and essential oils, in holy basil have not been studied. Trichome characteristics, including types, diameter, volume and density, were not related to aroma levels of the five holy basil accessions studied in the present work. Eugenol, (E)-caryophyllene, and β-elemene were major constituents of the essential oils from leaves of most accessions, whereas methyl eugenol was found only in accessions with weak aroma. Based on the chemical compositions, accessions with low aroma level were clustered separately from those with higher levels. A similar result was also revealed by e-nose analysis. Our results demonstrate that major essential oil constituents appear to be responsible for the difference in aroma level between the holy basil accessions. Accessions with stronger holy basil aroma were rich in eugenol, while lacking in methyl eugenol, and could be distinguished from those with weaker aroma that were methyl eugenol-rich, but deficient in eugenol.

Wild Species Veronica officinalis L. and Veronica saturejoides Vis. ssp. saturejoides—Biological Potential of Free Volatiles

Extracts from plants of the genus Veronica have been and continue to be used in traditional medicine to treat various diseases throughout the world. Although often considered a weed, many scientific reports demonstrate that these plants are a source of valuable biologically active compounds and their potential for horticulture should be investigated and considered. In this study, free volatile compounds of essential oils (EO) and hydrosols were extracted from two species: Veronica officinalis, which is most commonly used in traditional medicine, and Veronica saturejoides, an endemic plant that could be obtained by cultivation in horticulture. Volatiles were analyzed by gas chromatography coupled with mass spectrometry (GC, GC-MS). The most abundant compounds identified in the EOs were hexadecanoic acid in V. officinalis EO and caryophyllene oxide in V. saturejoides EO. The hydrosols were characterized by a high abundance of caryophyllene oxide in V. saturejoides hydrosol and of p-vinyl guaiacol for V. officinalis hydrosol. The sites where the volatile compounds are synthesized and stored were analyzed using SEM (Scanning Electron Microscopy); glandular and non-glandular trichomes were detected on stems, leaves and the calyx. Further, to investigate the activity of the free volatile compounds against pathogens, isolated volatile compounds were tested on the antiphytoviral activity against tobacco mosaic virus (TMV) infection. The hydrosols of both investigated species and EO of V. officinalis showed significant antiphytoviral activity. To further investigate the biological potential of these extracts they were also tested for their antiproliferative and antioxidant activities. The results indicate that these compounds are a valuable source of potential anticancerogenic agents that should be investigated in future studies. The presented results are the first report of hydrosol and EO activity against TMV infection, suggesting that these extracts from Veronica species may be useful as natural-based antiphytoviral agents.

Effect of Microwave Treatment on the Profile of Volatile Compounds and Characteristics of White Pepper (Piper nigrum L.) Essential Oil

Microwave treatment on white pepper was conducted to damage cell tissue to facilitate the distillation and increase the yield of essential oils. The research objective was to determine the effect of pepper varieties and microwave treatment on the profiles of volatile compounds and the characteristics of white pepper essential oils. The research was conducted with 50 grams of white pepper placed into a 15 cm diameter petri dish and put in a microwave oven at the power of 600 watts for 90 seconds then white pepper milled by hammer mill. Essential oils were obtained using the water distillation method then were tested for their characteristics and compounds using Gas chromatography-Mass Spectrometry (GC-MS). White pepper was analyzed using the water content, piperine content, and its cell tissue microstructure was analyzed using Scanning Electron Microscope (SEM). The results showed that different pepper as accession produced different profiles of volatile compounds, characteristics, and antioxidant activity (p<0.05). The number of volatile compounds of white pepper essential oils identified by GC-MS was 42, where the largest compound was β-caryophyllene (50.51%). Microwave treatment damaged the cell wall of white pepper, lowered water content (17.43%), increased piperine content (10.57%) and essential oil yield (25%), and changed the profiles of volatile compounds of essential oils of Lampung daun lebar accession. Color became bluer (b*value rises by 201.99%), increased specific gravity (1.27%) and antioxidant activity (7.4%), decreased solubility in 95% ethanol (17.95%) and acid number (20.8%) while the refractive index was not affected by pepper accessions and microwave treatment.

Essential oils-loaded electrospun chitosan-poly(vinyl alcohol) nonwovens laminated on chitosan film as bilayer bioactive edible films

Direct application of active and volatile compounds of essential oils (EOs) is ineffective in food and uncontrolled release of these compounds may be undesirable from sensory and antimicrobial efficacy standpoints. The present study aimed to develop and characterize the physical and antimicrobial properties of casting composite chitosan (CS) thin films laminated with electrospun nonwovens loaded with Zataria multiflora (ZEO) and cinnamon (CEO) targeting for active food packaging purposes. The composite structures were incorporated with various amounts of ZEO and CEO blend to enhance their antimicrobial and physical properties. There was no significant difference between antibacterial activity of the films containing EOs in both Gram-positive and Gram-negative bacteria (P˂0.05). All the films had antifungal activity against A.flavus. The highest antioxidant activity was found in the composite CS film (97.20%) in comparison to other films (P˂0.05). Morphological analysis of bilayer films revealed homogeneous bead-free electrospun nanofibers with diameters of less than 200 nm. The addition of 0.5 %v/v CEO significantly enhanced the elongation in comparison to CS film (P˂0.05). Our results demonstrated that the properties of bilayer films were influenced by the contents of EOs and these findings may pave a way for introducing new category of active packaging staffs.

Yields and Composition of Persian Lime Essential Oils (Citrus latifolia) from Hau Giang province, Vietnam extracted by Three Different Extraction Methods

The essential oils (EOs) was extracted from Persian lime (Citrus latifolia) peels collected in Hau Giang province, Vietnam. Volatile compositions of EOs obtained by three extraction methods of hydrodistillation (HD), steam distillation (SD) and microwave extraction (ME) were analyzed and compared. The volatile compounds in EOs were analyzed based on gas chromatography-mass spectrometry (GC-MS). An amount of 3 ml/g, 2.3 ml/g and 4 ml/g of EOs was obtained from HD, SD and ME with twenty-one compounds were identified, accounting for 99% -100% of the total oil content. Limonene, β-pinene, α-pinene, γ-Terpinene, α-citral, β-citral and Sabinene are the major compound in essential oil. However, there were qualitative and quantitative differences between oil samples obtained by the three extraction methods. The difference is probably due to the influence of different environmental factors and specific characteristics of each extraction method. The results of this study will provide information on the content and chemical composition of Lemon peels. C. latifolia and serve as a stepping stone for further research into the applications of the compound to cosmetic, food and pharmaceutical products.

Chemical composition and evaluation of antioxidant activities, antimicrobial, and anti-melanogenesis effect of the essential oils extracted from Dalbergia pinnata (Lour.) Prain

Ethnopharmacological relevanceDalbergia pinnata (Lour.) Prain (D. pinnata) is a plant widely distributed in tropical and subtropical regions of Asia, Africa, and the Americas. In humans, it is used in the prevention and treatment of diseases such as respiratory system, digestive system, cardiovascular and cerebrovascular diseases. Aim of the studyThis study was aim to evaluate chemical composition, antioxidant activities, antimicrobial, and anti-melanogenesis properties of Essential oils (EO) from D. pinnata. Materials and methodsIn this paper, the EO of D. pinnata were extracted using the supercritical CO2 extraction method and purified by molecular distillation. The volatile compounds of EO were characterized using Gas Chromatography-Mass Spectrometer (GC-MS). The antioxidant activities were evaluated by the methods of 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging, 2, 2′-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radical scavenging assays. And two Gram-positive bacteria, three Gram-negative bacteria and a fungus were employed to evaluate the antimicrobial activity. The zebrafish was used as experimental model to evaluate the anti-melanogenesis effect of the EO from D. pinnata. ResultsThe EO of D. pinnata were obtained in a yield of 4.75% (v/w) calculated on dry weight basis. 14 volatile compounds could be detected and the predominant components include elemicin (91.06%), methyl eugenol (3.69%), 4-allyl-2,6-dimethoxyphenol (1.16%), and whiskey lactone (0.55%). The antioxidant assay showed that the EO could scavenge DPPH (IC50 values of 0.038 mg/mL) and ABTS (IC50 value of 0.032 mg/mL) free radical, indicating that the EO had strong antioxidant activity. The results of antimicrobial test showed that Staphylococcus aureus was most sensitive to EO with minimal inhibitory concentration (MIC) of 0.78 μL/mL, followed by Streptococcus pyogenes (6.25 μL/mL) and Candida albicans (12.5 μL/mL). Gram-negative strains, including Escherichia coli, Pseudomonas aeruginosa and Salmonella typhimurium, were slightly affected by the EO. Additionally, EO from D. pinnata could reduce tyrosinase activity and melanin synthesis of zebrafish embryos in dose-dependent manner. And EO exhibited the more obvious anti-melanogenic effect compared with the positive control arbutin at the same dose (30 mg/L). ConclusionsOur results validated the main activities attributed to D. pinnata for its antimicrobial and antioxidant. In addition, the potent inhibitory impacts of EO on the pigmentation provides a theoretical basis for the in-depth study of the EO from D. pinnata and their application in pharmaceutical and cosmetic industries.

Inclusion Complex of Exocarpium Citri Grandis Essential Oil with β‐Cyclodextrin: Characterization, Stability, and Antioxidant Activity

The purpose of this study was to produce and characterize an inclusion complex between β-cyclodextrin (β-CD) and Exocarpium Citri Grandis essential oil (EEO), and to evaluate its antioxidant properties. The volatile compounds of EEO were characterized by gas chromatography-mass spectrometer. A comparison of the β-CD, EEO, and the physical mixture with the inclusion complex revealed differences in their thermal stabilities and morphologies, which confirmed the formation of the β-CD-EEO inclusion complex. Complexed with β-CD, the β-CD-EEO inclusion complex showed a higher stability and antioxidant activity when compared with physical mixture and EEO. Therefore, β-CD can be used to form inclusion complexes with EEO to expand its potential applications in the food and drug industries. PRACTICAL APPLICATION: Exocarpium Citri Grandis is rich in essential oil and other ingredients. The optimized extraction, constituent composition, and encapsulation of EEO in β-CD were investigated in this study. The results showed that the encapsulation process increased the antioxidant activity and stability of EEO, which provides both fundamental and practical knowledge for the application of EEO in the food and drug industries.