Characterizing the Interactions of Cell-Membrane-Disrupting Peptides with Lipid-Functionalized Single-Walled Carbon Nanotubes.

Lipid-functionalized single-walled carbon nanotubes (SWNTs) have garnered significant interest for their potential use in a wide range of biomedical applications. In this work, we used molecular dynamics simulations to study the equilibrium properties of SWNTs surrounded by the phosphatidylcholine (POPC) corona phase and their interactions with three cell membrane disruptor peptides: colistin, TAT peptide, and crotamine-derived peptide. Our results show that SWNTs favor asymmetrical positioning within the POPC corona, so that one side of the SWNT, covered by the thinnest part of the corona, comes in contact with charged and polar functional groups of POPC and water. We also observed that colistin and TAT insert deeply into the POPC corona, while crotamine-derived peptide only adsorbs to the corona surface. In separate simulations, we show that three examined peptides exhibit similar insertion and adsorption behaviors when interacting with POPC bilayers, confirming that peptide-induced perturbations to POPC in conjugates and bilayers are similar in nature and magnitude. Furthermore, we observed correlations between the peptide-induced structural perturbations and the near-infrared emission of the lipid-functionalized SWNTs, which suggest that the optical signal of the conjugates transduces the morphological changes in the lipid corona. Overall, our findings indicate that lipid-functionalized SWNTs could serve as simplified cell membrane model systems for prescreening of new antimicrobial compounds that disrupt cell membranes.

Diversity of Essential Oil-Secretory Cells and Oil Composition in Flowers and Buds of Magnolia sirindhorniae and Its Biological Activities.

Magnolia sirindhorniae Noot. & Chalermglin produces fragrant flowers. The volatile oil secretary cells, quantity and quality as well as antioxidant and antimicrobial activities of the oils extracted from buds and flowers, have been investigated. The distribution of essential oil secretory cell in bud and flower revealed that the density and size of the oil cells were significantly higher in flowers compared to buds. In different floral parts, carpel has a higher oil cell density followed by gynophore and tepal. The histochemical analysis revealed the essential oil is synthesized in oil secretory cells. The volatile oil yield was 0.25 % in the buds and 0.50 % in flowers. GC/FID and GC/MS analysis identified 33 compounds contributing 83.2-83.5 % of the total essential oil composition. Linalool is the main constituent contributing 58.9 % and 51.0 % in the buds and flowers oils, respectively. The essential oil extracted from the flowers showed higher antimicrobial efficacy against Klebsiella pneumoniae and Staphylococcus aureus. Similarly, the essential oil isolated from the flowers depicts higher free radical scavenging, and antioxidant activity compared to buds' oil.

Role of 904 nm superpulsed laser-mediated photobiomodulation on nitroxidative stress and redox homeostasis in burn wound healing.

BACKGROUND: Burn wound healing is delayed due to several critical factors such as sustained inflammation, vascular disorder, neuropathy, enhanced proteolysis, infection, and oxidative stress. Burn wounds have limited oxygen supply owing to compromised blood circulation. Hypoxic burn milieu leads to free radicals overproduction incurring oxidative injury, which impedes repair process causing damage to cell membranes, proteins, lipids, and DNA. Photobiomodulation (PBM) with 904 nm superpulsed laser had shown potent healing efficacy via attenuating inflammation while enhancing proliferation, angiogenesis, collagen accumulation, and bioenergetic activation in burn wounds. METHODS: This study investigated the effects of 904 nm superpulsed laser at 0.4 mW/cm2 average power density, 0.2 J/cm2 total energy density, 100 Hz frequency, and 200 ns pulse width for 10 min daily for seven days postburn injury on nitroxidative stress, endogenous antioxidants status, and redox homeostasis. RESULTS: Photobiomodulation treatment significantly decreased reactive oxygen species, nitric oxide, and lipid peroxidation levels as compared to non-irradiated control. Further, protective action of PBM against protein oxidative damage was evidenced by reduced protein carbonylation and advanced oxidation protein product levels along with significantly enhanced endogenous antioxidants levels of SOD, catalase, GPx, GST, reduced glutathione, and thiol (T-SH, Np-SH, P-SH). Biochemical changes aid in reduction of oxidative stress and maintenance of redox homeostasis, which further well corroborated by significantly up-regulated protein expression of Nrf 2, hemeoxygenase (HO-1), and thioredoxin reductase 2 (Txnrd2). CONCLUSION: Photobiomodulation with 904 nm superpulsed laser led to reduction of nitroxidative stress, induction of endogenous antioxidants, and maintenance of redox homeostasis that could play a vital role in augmentation of burn wound healing.

Effects of Pulsed 810 nm Al-Ga-As Diode Laser on Wound Healing Under Immunosuppression: A Molecular Insight.

BACKGROUND AND OBJECTIVES: Dysregulated inflammation is one of the major contributing factors for the prevalence of non-healing chronic wound in immunosuppressed subjects. Photobiomodulation (PBM) has emerged as a potential non-thermal, light-based therapeutic healing intervention for the treatment of impaired wounds. STUDY DESIGN/MATERIALS AND METHODS: The present study delineates the underlying molecular mechanisms of PBM 810 nm laser-induced full-thickness cutaneous wound repair in immunosuppressed rats at continuous and pulsed wave-mode with power-density of 40 mW/cm 2 , fluence 22.6 J/cm 2 for 10 minutes daily for 7 post-wounding days. Molecular markers were assessed using biochemical, enzyme-linked immunosorbent assay quantification, enzyme kinetics and immunoblots analyses pertaining to inflammation, oxidative stress, cell survival, calcium signaling, and proliferation cascades. RESULTS: Results distinctly revealed that pulsed 810 nm (10 Hz) PBM potentially influenced the cell survival and proliferation signaling pathway by significantly upregulated phospho-protein kinase B(phospho-Akt), phospho-extracellular-signal-regulated kinase 1 (ERK1), transient receptor potential vanilloid-3 (TRPV3), Ca2+ , calmodulin, transforming growth factor-ß1 (TGF-ß1), TGF-ßR3, and Na + /K + -ATPase pump levels. PBM treatment resulted in reduction of exaggerated inflammatory responses evident by significantly repressed levels of interleukin-1ß (IL-1ß), IL-6, cyclooxygenase 2 (COX-2), and substance-P receptor (SPR), as well as inhibited apoptotic cell death by decreasing p53, cytochrome C, and caspase 3 levels (P < 0.05), which, in turn, effectively augment the wound repair in immunosuppressed rats. PBM treatment also lowered 4-hydroxynoneal (HNE) adduct level and NADP/NADPH ratio and upregulated the GRP78 expression, which might culminate into reduced oxidative stress and maintained the redox homeostasis. CONCLUSIONS: Taken together, these findings would be helpful in better understanding of the molecular aspects involved in pulsed 810 nm laser-mediated dermal wound healing in immunosuppressed rats through regulation of cell survival and proliferation via Ca2+ -calmodulin, Akt, ERK, and redox signaling. Lasers Surg. Med. © 2019 Wiley Periodicals, Inc.

Combination of medicinal honey and 904 nm superpulsed laser-mediated photobiomodulation promotes healing and impedes inflammation, pain in full-thickness burn.

Burn wound is a complex multi-factorial pathophysiology producing excruciating pain and psychological discomfort among patients, which imposes a major burden on the healthcare system. Multi-target therapy focuses on augmented healing by regulating different phases of tissue repair. Recently, photobiomodulation (PBM)-induced wound healing has achieved profound impetus as a non-invasive, drug-free biophysical therapeutic approach. On the other hand, medicinal honey known to possess antibacterial and immunomodulatory properties and is being used as an effective treatment option for infected wounds. The present study aimed to determine whether the combination of medicinal honey and PBM using superpulsed 904 nm laser treatment could additively accelerate full-thickness burn wound repair in rats. Animals were randomly allocated into 4 experimental groups: control (C), PBM superpulsed 904 nm laser treated (PBMT), honey treated (HT) and combined treatment (CT). The dual treatment exhibited an enhanced wound area contraction and hexosamine content as compared to the other groups. Histopathological analysis revealed increased cellular proliferation, extracellular matrix accumulation and decreased inflammation in the CT group. Further, the CT group demonstrated synergistically attenuated inflammation, pain and enhanced cell adhesion, migration as evidenced by significantly reduced protein expression of TNF-α, NF-κB, IL-1ß, COX-2, substance-P receptor and up-regulation of fibronectin, respectively as compared with the other groups. Thus, the findings of present study signify that the combination of medicinal honey and PBMT accelerates the repair process of burn wounds. The study showed that therapeutic efficacy of 904 nm superpulsed laser-mediated PBM augments in the presence of medicinal honey by enhancing cellular proliferation and attenuation of inflammation and pain in burn wound healing.

Essential oil from waste leaves of Curcuma longa L. alleviates skin inflammation.

BACKGROUND: Curcuma longa L. is an important industrial crop used by medicinal and cosmetic industries in the world. Its leaves are a waste material after harvesting rhizomes. The aim of the study was to evaluate the chemical and pharmacological profile of essential oil from waste leaves of Curcuma longa (EOCl) against skin inflammation. METHODS: EOCl was subjected to gas chromatography (GC) analysis for identification of essential oil constituents and its anti-inflammatory evaluation through in vitro and in vivo models. RESULTS: Chemical fingerprinting using GC and GC-MS analysis of EOCl revealed the presence of 11 compounds, representing 90.29% of the oil, in which terpinolene (52.88%) and α-phellandrene (21.13%) are the major components. In the in vitro testing EOCl inhibited the production of pro-inflammatory cytokines (TNF-α, IL-6, IL-1ß) in lipopolysaccharide (LPS) and 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced inflammation in the human keratinocyte cell line (HaCaT). Topical application of EOCl produced anti-inflammatory effects by reducing ear thickness, ear weight and ameliorating the level of pro-inflammatory cytokines (TNF-α, IL-6, IL-1ß) at protein and mRNA levels as well as regulating the overproduction of oxidative markers and restoring the histopathological damage in a TPA-induced mouse model of inflammation. CONCLUSION: These findings of topical anti-inflammatory properties of EOCl provide a scientific basis for medicinal use of this plant material against inflammatory disorders.

Enantioselective GC Analysis of C3-Oxygenatedp-Menthane type Indian Mentha spicata var. viridis 'Ganga' Essential Oil.

Essential oil of Mentha spicata L. var. viridis 'Ganga', an indigenously developed variety, was chemically profiled using various gas chromatographic techniques. Piperitenone oxide was characterized as the most exclusive constituent (69.7%) along with a new C3-oxygenated p-menthane alcohol,- diosphenolene (1.6%). Enantiomeric discrimination revealed (4S)-(-)-limonene, (R)-(-)-linalool and (lS,2S)-(+)-piperitenone oxide as predominant enantiomers. The oil contained mainly C3-oxygenated p-menthane monoterpenoids, which are distinctive of peppermint, instead of the characteristic C6-oxygenated class of spearmint. The present findings will aid in understanding the pathway and cause of C3-oxygenation in a spearmint taxon. The essential oil and pure piperitenone oxide showed growth inhibiting properties and thus, may be utilized in antifungal preparations for disease management of medicinal and aromatic plants.

Noninvasive red and near-infrared wavelength-induced photobiomodulation: promoting impaired cutaneous wound healing.

The innumerable intricacies associated with chronic wounds have made the development of new painless, noninvasive, biophysical therapeutic interventions as the focus of current biomedical research. Red and near-infrared light-induced photobiomodulation therapy appears to emerge as a promising drug-free approach for promoting wound healing, reduction in inflammation, pain and restoration of function owing to penetration power in conjunction with their ability to positively modulate the biochemical and molecular responses. This review will describe the physical properties of red and near-infrared light and their interaction with skin and highlight their efficacy of wound repair and regeneration. Near-infrared (800-830 nm) was found to be the most effective and widely studied wavelength range followed by red (630-680 nm) and 904 nm superpulsed light exhibiting beneficial photobiomodulatory effects on impaired dermal wound healing.

Photobiomodulation with Pulsed and Continuous Wave Near-Infrared Laser (810 nm, Al-Ga-As) Augments Dermal Wound Healing in Immunosuppressed Rats.

Chronic non-healing cutaneous wounds are often vulnerable in one or more repair phases that prevent normal healing and pose challenges to the use of conventional wound care modalities. In immunosuppressed subject, the sequential stages of healing get hampered, which may be the consequences of dysregulated or stagnant wound inflammation. Photobiomodulation (PBM) or low-level laser (light) therapy (LLLT) emerges as a promising drug-free, non-invasive biophysical approach for promoting wound healing, reduction of inflammation, pain and restoration of functions. The present study was therefore undertaken to evaluate the photobiomodulatory effects of 810 nm diode laser (40 mW/cm2; 22.6 J/cm2) with pulsed (10 and 100 Hz, 50% duty cycle) and continuous wave on full-thickness excision-type dermal wound healing in hydrocortisone-induced immunosuppressed rats. Results clearly delineated that 810 nm PBM at 10 Hz was more effective over continuous and 100 Hz frequency in accelerating wound healing by attenuating the pro-inflammatory markers (NF-kB, TNF-α), augmenting wound contraction (α-SM actin), enhancing cellular proliferation, ECM deposition, neovascularization (HIF-1α, VEGF), re-epithelialization along with up-regulated protein expression of FGFR-1, Fibronectin, HSP-90 and TGF-ß2 as compared to the non-irradiated controls. Additionally, 810 nm laser irradiation significantly increased CCO activity and cellular ATP contents. Overall, the findings from this study might broaden the current biological mechanism that could be responsible for photobiomodulatory effect mediated through pulsed NIR 810 nm laser (10 Hz) for promoting dermal wound healing in immunosuppressed subjects.

Photobiomodulatory effects of superpulsed 904nm laser therapy on bioenergetics status in burn wound healing.

Burn wounds exhibit impaired healing as the progression through the normal sequential stages of tissue repair gets hampered by epidermal barrier disruption, compromised blood circulation, abrogated defence mechanism, pathologic inflammation, and septicemia. Our earlier results reported that superpulsed 904nm LLLT enhanced healing and attenuated inflammatory response in burn wounds. The present study investigated the effect of superpulsed 904nm LLLT (200ns pulse width; 100Hz; 0.7mW mean output power; 0.4mW/cm(2) average irradiance) on biochemical and molecular markers pertaining to bioenergetics and redox homeostasis on full-thickness burn wounds in experimental rats. Results indicated that superpulsed laser irradiation for 7days post-wounding propelled the cellular milieu towards aerobic energy metabolism as evidenced by significantly enhanced activities of key energy regulatory enzymes viz. HK, PFK, CS and G6PD, whereas LDH showed reduced activity as compared to the non-irradiated controls. LLLT showed a significant increased CCO activity and ATP level. Moreover, LLLT also regulated redox homeostasis as evidenced by enhanced NADPH levels and decreased NADP/NADPH ratio. Western blot analysis demonstrated that LLLT produced an up-regulation of GLUT1, pAMPKα and down-regulation of glycogen synthase1 (GS1). Our findings suggest that superpulsed 904nm LLLT augments burn wound healing by enhancing intracellular energy contents through modulation of aerobic metabolism for maximum energy output. Bioenergetic activation and maintenance of redox homeostasis could be one of the noteworthy mechanisms responsible for the beneficial NIR photobiomodulatory effect mediated through superpulsed 904nm LLLT in burn wound healing.

Superpulsed (Ga-As, 904 nm) low-level laser therapy (LLLT) attenuates inflammatory response and enhances healing of burn wounds.

Low-level laser therapy (LLLT) using superpulsed near-infrared light can penetrate deeper in the injured tissue and could allow non-pharmacological treatment for chronic wound healing. This study investigated the effects of superpulsed laser (Ga-As 904 nm, 200 ns pulse width; 100 Hz; 0.7 mW mean output power; 0.4 mW/cm(2) average irradiance; 0.2 J/cm(2) total fluence) on the healing of burn wounds in rats, and further explored the probable associated mechanisms of action. Irradiated group exhibited enhanced DNA, total protein, hydroxyproline and hexosamine contents compared to the control and silver sulfadiazine (reference care) treated groups. LLLT exhibited decreased TNF-α level and NF-kB, and up-regulated protein levels of VEGF, FGFR-1, HSP-60, HSP-90, HIF-1α and matrix metalloproteinases-2 and 9 compared to the controls. In conclusion, LLLT using superpulsed 904 nm laser reduced the inflammatory response and was able to enhance cellular proliferation, collagen deposition and wound contraction in the repair process of burn wounds. Photomicrographs showing no, absence inflammation and faster wound contraction in LLLT superpulsed (904 nm) laser treated burn wounds as compared to the non-irradiated control and silver sulfadiazine (SSD) ointment (reference care) treated wounds.

Wound healing activity of an aqueous extract of the Lingzhi or Reishi medicinal mushroom Ganoderma lucidum (higher Basidiomycetes).

The Lingzhi or Reishi medicinal mushroom Ganoderma lucidum (higher Basidiomycetes) is popular because of its health-promoting properties. The effects of G. lucidum extract on cancer, hypertension, hypercholesterolemia, and hepatitis have been reported by many researchers. This investigation was undertaken to evaluate the healing efficacy of an aqueous lyophilized extract of G. lucidum from the Indian Himalayan region on dermal excision wound in experimental rats. The extract used in the study was found to be rich in total polyphenol and flavonoid contents. The healing efficacy was comparatively assessed with a reference povidone-iodine ointment. The G. lucidum extract showed significant enhanced healing activity, evidenced by an increase in wound contraction, collagen accumulation (hydroxyproline), hexosamine, and total protein contents. Histopathological findings further supported the biochemical indices. The results suggest that aqueous lyophilized extract of G. lucidum possesses significant wound-healing activity.

Characterization of volatile components of Zingiber roseum essential oil using capillary GC on modified cyclodextrins.

The essential oil from different parts of Zingiber roseum plants was extracted by hydrodistillation, and analyzed using enantio-GC, capillary-GC and GC-MS. Two chiral selectors, 6-tert-butyldimethylsilyl-2,3-diethyl-beta-cyclodextrin (TBDE-beta-CD), and 2,3,6-methyl-beta-cyclodextrin (PM-beta-CD) doped into 14% cyanopropylphenyl/86% dimethylpolysiloxane, and 35% diphenyl/65% dimethylpolysiloxane, respectively were compared in order to clarify the stereochemistry and enantioselectivity of terpenoids using chiral gas chromatography. The enantiomeric excess for (1R)-(+)-alpha-pinene, (1R)-(+)-beta-pinene, and (R)-(+)-limonene were characteristic for the rhizome. In TBDE-beta-cyclodextrin coated chiral columns, a significant increase in separation factor (alpha) for beta-pinene, limonene, linalool and alpha-terpineol enantiomers was observed when compared with methyl substituted beta-cyclodextrin. The increase in chain length of the alkyl substituents may be the possible cause for enantiomer separation in beta-cyclodextrin cavity. In addition, enantioreversal of alpha-pinene enantiomers in 6-tert-butyldimethylsilyl-2,3-diethyl-beta-cyclodextrin was noticed as a unique feature. The enantiomeric compositions of Z. roseum fruit and flower essential oils were similar, but, in contrast, the rhizome oil contained an entirely different composition. Therefore, these results aid in the authentication of the natural origin of Z. roseum essential oils.

Variation in the volatile constituents of different plant parts of Ligusticopsis wallichiana from western Himalaya, India.

The essential oil composition of the leaves, stem, flowers and roots of Ligusticopsis wallichiana (DC.) Pimenov & Kljuykov were analyzed by GC-FID and GC-MS methods. Forty-five constituents, forming 93.2%-97.8% of the oil compositions, were dominated by acetylenic (31.5%-92.8%) compounds and sesquiterpenoids (0.3%-44.4%). The leaf essential oil was mainly composed 3,5-nonadiyne (35.8%), beta-selinene (20.9%), alpha-funebrene (10.1%) and (Z)-falcarinol (6.1%). The stem oil was dominated by acetylenic compounds (73.8%) represented by 3,5-nonadiyne (67.8%) and (Z)-falcarinol (5.7%). On the contrary, the major components of the flower essential oil were sesquiterpenoids (37.5%), such as germacrene D (16.6%), alpha-funebrene (7.4%), and acetylenic compounds (31.5%), such as (Z)-falcarinol (21.0%) and 3,5-nonadiyne (10.0%). Monoterpenoids constituted 23.9% of the flower oil with limonene (19.9%) as the single major constituent. The essential oil of the roots was dominated by 3,5-nonadiyne (90.5%). The results showed considerable qualitative and quantitative variations in the essential oil compositions of the different plant parts of L. wallichiana. (Z)-Falcarinol (1.9%-21.0%) and alpha-funebrene (0.1%-10.1%) were reported for the first time from the essential oils of L. wallichiana.

Monitoring the emission of volatile organic compounds from flowers of Jasminum sambac using solid-phase micro-extraction fibers and gas chromatography with mass spectrometry detection.

Solid-phase micro-extraction (SPME) was studied as a solvent free alternative method for the extraction and characterization of volatile compounds in intact and plucked flowers of Jasminum sambac at different day time intervals using gas chromatography (GC-FID) and gas chromatography-quadrupole mass spectrometry. The analytes identified included alcohols, esters, phenolic compounds, and terpenoids. The main constituents identified in the flower aroma using different fibers were cis-3-hexenyl acetate, (E)-beta-ocimene, linalool, benzyl acetate, and (E,E)-alpha-farnesene. The benzyl acetate proportion decreased from morning to afternoon and then increased in evening collections. PDMS fiber showed a high proportion of (E,E)-alpha-farnesene in jasmine floral aroma. Among other constituents identified, cis-3-hexenyl acetate, linalool, and benzyl acetate were major aroma contributors in plucked and living flowers extracts using PDMS/DVB, Carboxen/PDMS, and DVB/Carboxen/PDMS fibers. PDMS/DVB recorded the highest emission for benzyl acetate while the (E)-beta-ocimene proportion was highest in DVB/Carboxen/PDMS when compared with the rest. The highest linalool content, with increasing proportion from morning to noon, was found using mixed coating fibers. Almost negligible volatile adsorption was recorded for the polyacrylate fiber for intact flower aroma, whereas it was most effective for benzyl acetate, followed by indole under plucked conditions. Moreover, the highest amounts extracted, evaluated from the sum of peak areas, were achieved using Carboxen/PDMS, and DVB/Carboxen/PDMS. Introduction of a rapid, and solvent free SPME method for the analysis of multicomponent volatiles can be successfully employed to monitor the extraction and characterization of flower aroma constituents.

Variation in the volatile constituents of Artemisia annua var. CIM-Arogya during plant ontogeny.

The essential oils yield and composition of the aerial parts of A. annua var. CIM-Arogya grown in Uttarakhand, India were analyzed and compared by capillary GC and GC-MS at different stages of development. The analysis led to the identification of 81 constituents forming 91.0%-97.1% of the essential oils compositions. The essential oil content of the aerial parts was found to vary from 0.3% to 0.7% at different stages of growth. A. annua crop harvested at full flowering and seed setting stage gave higher yield of essential oil (0.6%, 0.7%) than that harvested at pre flowering (0.5%), late vegetative (0.4%, 0.5%), mid vegetative (0.4%, 0.4%) and early vegetative stages (0.3%, 0.3%). The essential oils at different stages of growth showed monoterpenoids (38.5%-72.0%) and sesquiterpenoids (22.2%-48.2%) as major grouped constituents. The major constituents identified were camphor (22.8%-42.6%), 1,8-cineole (3.7%-8.4%), linalool (<0.1%-11.9%), beta-caryophyllene (2.0%-9.2%), (E)-beta-farnesene (1.3%-8.5%), germacrene D (0.5%-7.3%) and 1-epi-cubenol (0.7%-5.2%) in essential oil samples collected at different crop stages.

Volatiles of Callicarpa macrophylla: a rich source of selinene isomers.

Variations in volatile composition of the leaf and fruit oils from Callicarpa macrophylla were compared, using GC-FID, Kovat's Index calculation, and GC/MS. The oils were rich in selinene derivatives. The fruit oil was comprised of 41.6% beta-selinene and 6% alpha-selinene. The leaves from both the harvests contained 29% and 20% beta-selinene and 1.7% alpha-selinene. In addition, dendrolasin, a potential perfumery natural furanoid sesquiterpenoid, was a characteristic of both leaf and fruit essential oils.

Essential oil composition of Thymus serpyllum cultivated in the Kumaon region of western Himalaya, India.

The hydrodistilled essential oil of aerial parts of Thymus serpyllum L. (Lamiaceae), cultivated in the Kumaon region of western Himalaya was analyzed by GC and GC-MS. Twenty-nine compounds, representing 91.8% of the oil, were identified. The major components were thymol (58.8%), p-cymene (5.7%), thymol methyl ether (4.0%), borneol (3.8%), sabinene (3.4%), gamma-terpinene (3.4%) and carvacrol methyl ether (3.2%).

Enantiomeric composition of (3R)-(-)- and (3S)-(+)-linalool in various essential oils of Indian origin by enantioselective capillary gas chromatography-flame ionization and mass spectrometry detection methods.

Enantiomeric ratios of linalool have been determined in various authentic essential oils of Indian origin using 10% heptakis(2,3-di-O-methyl-6-O-tert-butyldimethylsilyl)-beta-cyclodextrin as a chiral stationary phase. A complete enantiomeric excess (ee) for (3S)-(+)-linalool was characteristic of Lippia alba and Cinnamomum tamala leaf oils while less than 90% excess was noticed in Zanthoxylum armatum leaf, Zingiber roseum root/rhizome and Citrus sinensis leaf oils. On the contrary, an enantiomeric excess of (3R)-(-)-linalool characterizes essential oils of basil (100% for Ocimum basilicum) and bergamot mint (72 to 75% for Mentha citrata). Notably, some essential oils containing both enantiomers in equal ratios or in racemic forms are rose, geranium, lemongrass and Origanum. The enantiomeric composition studies are discussed as indicators of origin authenticity and quality of essential oil of Indian origin.