Hydrolates from lavender (Lavandula angustifolia)--their chemical composition as well as aromatic, antimicrobial and antioxidant properties

Phytochemical Composition and Antimicrobial Properties of New Lavandula angustifolia Ecotypes

The purpose of this study was to characterize ethanol extracts from leaves and flowers of two ecotypes (PL-intended for industrial plantations and KC-intended for cut flowers) of Lavandula angustifolia Mill. The plant was cultivated in 2019 in southern Poland as part of a long-term research plan to develop new varieties resistant to difficult environmental conditions. The collected leaves and flowers were used to prepare ethanol extracts, which were then analyzed in terms of phytochemical composition and antioxidant, bactericidal, and fungicidal properties. Using UPLC techniques, 22 compounds belonging to phenolic acids and flavonoids were identified. UPLC test results indicated that ethanol extracts from leaves and flowers differ in phytochemical composition. Lower amounts of phenolic acids and flavonoids were identified in leaf extracts than in flower extracts. The predominant substances in the flower extracts were rosmarinic acid (829.68-1229.33 µg/g), ferulic acid glucoside III (810.97-980.55 µg/g), and ferulic acid glucoside II (789.30-885.06 µg/g). Ferulic acid glucoside II (3981.95-6561.19 µg/g), ferulic acid glucoside I (2349.46-5503.81 µg/g), and ferulic acid glucoside III (1303.84-2774.17 µg/g) contained the highest amounts in the ethanol extracts of the leaves. The following substances were present in the extracts in trace amounts or at low levels: apigenin, kaempferol, and caftaric acid. Leaf extracts of the PL ecotype quantitatively (µg/g) contained more phytochemicals than leaf extracts of the KC ecotype. The results obtained in this study indicate that antioxidant activity depends on the ecotype. Extracts from the PL ecotype have a better ability to eliminate free radicals than extracts from the KC ecotype. At the same time, it was found that the antioxidant activity (total phenolic content, ABTS•+, DPPH•, and FRAP) of PL ecotype leaf extracts was higher (24.49, 177.75, 164.88, and 89.10 μmol (TE)/g) than that determined in flower extracts (15.84, 125.05, 82.35, and 54.64 μmol (TE)/g). The test results confirmed that leaf and flower extracts, even at low concentrations (0.313-0.63%), significantly inhibit the growth of selected Gram-negative and Gram-positive bacteria and Candida yeasts. Inhibition of mold growth was observed at a dose extract of at least 1 mL/100 mL.

Disclosing the potential of Cupressus leylandii A.B. Jacks & Dallim, Eucalyptus globulus Labill., Aloysia citrodora Paláu, and Melissa officinalis L. hydrosols as eco-friendly antimicrobial agents

Antimicrobial resistance is a major global health concern, threatening the effective prevention and treatment of infections caused by microorganisms. These factors boosted the study of safe and green alternatives, with hydrosols, the by-products of essential oils extraction, emerging as promising natural antimicrobial agents. In this context, four hydrosols obtained from Cupressus leylandii A.B. Jacks & Dallim, Eucalyptus globulus Labill., Aloysia citrodora Paláu and Melissa officinalis L. were studied. Their chemical composition comprises neral, geranial, 1,8-cineole, terpinen-4-ol, and oplopanonyl acetate, compounds with recognised antimicrobial activity. Concerning antimicrobial activity, significant differences were found using different hydrosol concentrations (10-20% v/v) in comparison to a control (without hydrosol), showing the potential of the tested hydrosols to inhibit the microbial growth of Escherichia coli, Staphylococcus aureus, and Candida albicans. A. citrodora hydrosol was the most effective one, inhibiting 90% of E. coli growth and 80% of C. albicans growth, for both hydrosol concentrations (p < 0.0001). With hydrosol concentration increase, it was possible to observe an improved antimicrobial activity with significant reductions (p < 0.0001). The findings of this work indicate the viability of reusing and valuing the hydrosols, encouraging the development of green applications for different fields (e.g., food, agriculture, pharmaceuticals, and cosmetics).

Multistep Approach Points to Compounds Responsible for the Biological Activity and Safety of Hydrolates from Nine Lamiaceae Medicinal Plants on Human Skin Fibroblasts

As byproducts of essential oil distillation, hydrolates are used in natural cosmetics/biomedicine due to their beneficial skin effects. However, data on their safety with relevant biological targets, such as human skin cells, are scarce. Therefore, we have tested nine hydrolates from the Lamiaceae family with skin fibroblasts that are responsible for extracellular collagenous matrix builds. Thyme, oregano, and winter savoury hydrolates showed several times higher total phenolics, which correlated strongly with their radical scavenging and antioxidative capacity; there was no correlation between their viability profiles and the reducing sugar levels. No proteins/peptides were detected. All hydrolates appeared safe for prolonged skin exposure except for 10-fold diluted lavender, which showed cytotoxicity (~20%), as well as rosemary and lavandin (~10%) using viability, DNA synthesis, and cell count testing. Clary sage, oregano, lemon balm, and thyme hydrolates (10-fold diluted) increased fibroblast viability and/or proliferation by 10-30% compared with the control, while their viability remained unaffected by Mentha and winter savoury. In line with the STITCH database, increased viability could be attributed to thymol presence in oregano and thyme hydrolates in lemon balm, which is most likely attributable to neral and geranial. The proliferative effect of clary sage could be supported by alpha-terpineol, not linalool. The major volatile organic compounds (VOCs) associated with cytotoxic effects on fibroblasts were borneol, 1,8-cineole, and terpinene-4-ol. Further research with pure compounds is warranted to confirm the roles of VOCs in the observed effects that are relevant to cosmetic and wound healing aspects.

Comparative Studies on the Anti-Inflammatory and Apoptotic Activities of Four Greek Essential Oils: Involvement in the Regulation of NF-κΒ and Steroid Receptor Signaling

Essential oils (EOs) are well-known for their anti-fungal, anti-microbial, anti-inflammatory and relaxing activities. Steroid hormones, especially glucocorticoids, are also well-known for their anti-inflammatory activities and control of the hypothalamus-pituitary-adrenal (HPA) axis and glucose homeostasis. The biological activities of glucocorticoids render them the most widely prescribed anti-inflammatory drugs, despite their adverse side effects. In this study, comparative studies of the anti-inflammatory activities and interference with glucocorticoids receptor (GR) and estrogen receptor (ER) signaling of EOs from Greek Oregano, Melissa officinalis, Lavender and from the Chios Mastic, produced from the Greek endemic mastic tree, were performed in Human Embryonic Kidney 293 (HEK-293) cells. Chios Mastic (Mastiha) and oregano EOs exhibited the highest anti-inflammatory activities. The former showed a reduction in both NF-κB activity and protein levels. Mastic essential oil also caused a reduction in GR protein levels that may compensate for its boosting effect on dexamethasone (DEX)-induced GR transcriptional activation, ending up in no induction of the gluconeogenic phoshoenolpyruvate carboxykinase (PEPCK) protein levels that constitute the GR target. Oregano, Melissa officinalis and lavender EOs caused the suppression of the transcriptional activation of GR. Furthermore, the most active EO, that taken from Melissa officinalis, showed a reduction in both GR and PEPCK protein levels. Thus, the anti-inflammatory and anti-gluconeogenic activities of the EOs were uncovered, possibly via the regulation of GR signaling. Moreover, cytotoxic actions of Melissa officinalis and lavender EOs via the induction of mitochondrial-dependent apoptosis were revealed. Our results highlight these essentials oils' anti-inflammatory and apoptotic actions in relation to their implication on the regulation of steroid hormones' actions, uncovering their potential use in steroid therapy, with many applications in pharmaceutical and health industries as anti-cancer, anti-hyperglycemic and anti-inflammatory supplements.

Lavandula Species, Their Bioactive Phytochemicals, and Their Biosynthetic Regulation

Lavandula species are one of the most useful aromatic and medicinal plants and have great economic potential. The phytopharmaceutical contribution of the secondary metabolites of the species is unquestionable. Most recent studies have been focusing on the elucidation of the genetic background of secondary metabolite production in lavender species. Therefore, knowledge of not only genetic but especially epigenetic mechanisms for the regulation of secondary metabolites is necessary for the modification of those biosynthesis processes and the understanding of genotypic differences in the content and compositional variability of these products. The review discusses the genetic diversity of Lavandula species in relation to the geographic area, occurrence, and morphogenetic factors. The role of microRNAs in secondary-metabolites biosynthesis is described.

Thymus mastichina (L.) L. and Cistus ladanifer L. for skin application: chemical characterization and in vitro bioactivity assessment

ETHNOPHARMACOLOGICAL RELEVANCE

Thymus mastichina (L.) L. (TM) and Cistus ladanifer L. (CL) are two Portuguese autochthonous species with traditional skin application in folk medicine. TM is majorly known for its antiseptic and wound healing properties, as an external anti-inflammatory agent and for its application in folk cosmetics and hygiene products. Its use in acne vulgaris has also been reported. CL is traditionally used in remedies for wounds, ulcers and other skin ailments such as psoriasis and eczema. Its application has been found useful due to its anti-inflammatory, astringent, wound healing and antiseptic properties.

AIM OF THE STUDY

With this work, we aimed to investigate relevant bioactivities related with the traditional application of TM and CL essential oils (EOs) and hydrolates (by-products of EO production) in skin ailments. Specifically their in vitro antioxidant, anti-inflammatory, cytotoxic, wound healing and antimicrobial properties were evaluated. The chemical composition of both EOs and respective hydrolates was also characterized.

MATERIALS AND METHODS

Chemical characterization of EOs and hydrolates was performed by GC-FID and GC-MS. Cellular biocompatibility was evaluated using the MTT assay in macrophages (RAW 264.7) and fibroblasts (L929) cell lines. Anti-inflammatory activity was investigated by studying nitric oxide (NO) production by macrophages with Griess reagent. Wound healing potential was evaluated with the scratch-wound assay. The antioxidant potential was studied by the DPPH scavenging method. Antimicrobial activity was evaluated by broth microdilution assay against relevant microbial strains and skin pathogens, namely Staphylococcus aureus, Staphylococcus epidermidis, Cutibacterium acnes, Pseudomonas aeruginosa, Escherichia coli, Candida albicans and Aspergillus brasiliensis.

RESULTS

The major compounds present in TM and CL EOs were 1,8-cineole and α-pinene, respectively. 1,8-cineole and E-pinocarveol were the major compounds in the correspondent hydrolates. CL EO presented the highest anti-inflammatory potential [EC₅₀ = 0.002% (v/v)], still with significant cytotoxicity [IC₅₀ = 0.012% (v/v)]. TM preparations presented anti-inflammatory potential, also presenting higher biocompatibility. The same profile was present on fibroblasts regarding biocompatibility of the tested preparations. CL EO and hydrolate increased fibroblasts' migration by 155.7% and 148.4%, respectively. TM hydrolate presented a milder activity than CL hydrolate, but wound healing potential was still present, increasing cell migration by 125.1%. All preparations presented poor antioxidant capacity. CL EO presented higher antimicrobial activity, with MICs ranging from 0.06% (v/v) to 2% (v/v), against different microorganisms.

CONCLUSIONS

Anti-inflammatory and skin repairing potential were present for CL preparations. TM hydrolate presented an interesting biocompatible profile on both cell lines, also presenting anti-inflammatory potential. Furthermore, EOs from both species presented antimicrobial activity against a panel of different microorganisms. These in vitro bioactivities support some of their traditional skin applications, specifically regarding their antiseptic, wound healing and anti-inflammatory uses.

Spontaneous Officinal Plants in the Cilento, Vallo di Diano and Alburni National Park: Tradition, Protection, Enhancement, and Recovery

The aim of this study was to deepen our knowledge on the heritage and traditional uses of some medicinal plants of the Cilento, Vallo di Diano and Alburni National Park (Salerno province) and to evaluate their productive potential, in order to increase possible uses to recover and enhance the territory. Biometric surveys and biomass evaluation were carried out. Two types of aqueous extract were prepared using air-dried samples of six harvested species and tested for anti-germination activity on Lepidium sativum L. Hydrolates were recovered via steam distillation from aromatic species and the chemical-physical characteristics were determined. Historical evidence of industrial activity was collected in the territory of Sanza on Monte Cervati, where lavender essential oil has been distilled in the past century, and characterization of the essential oil components was carried out. The ethnobotanical uses detected mainly concerned traditional medicine and nutritional, ritual, or religious uses. The experimental results highlight that spontaneous medicinal plants could become potential sources of local economic development, with uses not only in the phytotherapeutic sector, but also in others, such as food and agriculture for weed control. Moreover, the evidence derived from industrial archeology could represent a further driving force for the enhancement of the territory's resources.

Current Trends for Lavender (Lavandula angustifolia Mill.) Crops and Products with Emphasis on Essential Oil Quality

Lavender is in the research spotlight due to its increasing economic importance, while market demand is expected to continue to grow. Among the hundreds of essential-oil-bearing plants, Lavandula angustifolia Mill. remains one of the most valuable. This paper explores the lavender chain timeline from crop to products, examining the expanding knowledge on the characteristics, phytochemical profile and functional potential of lavender that could lead to new products and uses. Lavender crops can be expanded without competing for productive land, instead using marginal, contaminated or unproductive land. A novel cultivation trend proposes leveraging agri-background biodiversity, arbuscular mycorrhiza and the natural enemies of pests for healthy crops. Together with breeding efforts targeting highly performant genotypes with complex volatile profiles coupled with resistance to specific biotic (particularly Phytoplasma) and abiotic (salt, heavy metals) stressors, industry could have a steady supply of high-quality raw material. Besides the expansion of the uses of essential oil in cosmetics, pharmaceuticals, food and environmental and agri-applications, novel channels have appeared for the use of the solid by-product, which is rich in polyphenols and polysaccharides; these channels have the potential to create additional streams of value. The stabilization and optimization of techno-functional delivery systems through the encapsulation of essential oil can extend shelf-life and enhance biological activity efficiency.

Antibiotic properties of Satureja montana L. hydrolate in bacteria and fungus of clinical interest and its impact in non-target environmental microorganisms

The aim of this study was to analyse the microbicidal and microbiostatic activity of S. montana hydrolate L., the water-soluble fraction of the hydro-distillation process used to obtain the essential oil, on 14 Gram-positive and Gram-negative bacteria and a fungus of clinical interest. To consider whether this hydrolate is a more environmentally friendly alternative to traditional antibiotics, its effect on non-target microorganisms in the aquatic and terrestrial environment was analysed using natural soil and river microorganism communities, characterized through 16S rRNA gene sequencing. Results showed that S. montana hydrolate was especially effective (25% v/v concentration) against Pasteurella aerogenes, Streptococcus agalactiae and Acinetobacter baumannii (priority 1, WHO). It was also a microbicide for a further 7 bacterial strains and the fungus Candida albicans (50% v/v concentration). The river and soil communities exposed to the hydrolate showed a decrease in their growth, as well as a decrease in their ability to metabolize polymers and carbohydrates (soil microorganisms) and polymers, carboxylic and ketone acids (river microorganisms). Hydrolates could be an alternative to conventional antibiotics, but their impact on the environment must be taken into account.

Campylobacter jejuni Biofilm Control with Lavandin Essential Oils and By-Products

The food industry is constantly struggling with one of the most prevalent biofilm-forming and food-borne pathogenic bacteria, Campylobacter jejuni. Different approaches are used to control biofilms in the food production chain, but none is fully effective. In this study, we aim to produce and determine the chemical profile of essential oils (EOs), ethanolic extracts of flowers prior to distillation (EFs), and ethanolic extracts of post-distillation waste material (EWMs) from Lavandula × intermedia ‘Bila’, ‘Budrovka’ St Nicholas and ‘Budrovka’, which were further used to reduce C. jejuni intercellular signaling, adhesion, and biofilm formation, as well as to test their antioxidant activity. Glycosides of hydroxycinnamic acids were the major constituents of both types of lavandin ethanolic extract, while linalool, linalyl acetate, 1,8-cineol, and camphor were the major compounds found in lavandin EOs. Tested EOs showed the best antibacterial activity with a minimal inhibitory concentration of 0.25 mg/mL. Lavandin EFs proved more effective in reducing C. jejuni intercellular signaling and adhesion compared to lavandin EOs and EWMs, while lavandin EOs showed a slightly better effect against biofilm formation. Interestingly, the best antioxidant activity was determined for lavandin EWMs. A positive and moderate correlation was found between the reduction of C. jejuni intercellular signaling and adhesion, as well as between adhesion and biofilm formation. These findings mean novel bacterial targets are of interest for biofilm control with alternative natural agents throughout the whole food production chain.

Anti-biofilm potential of Lavandula preparations against Campylobacter jejuni

New approaches for the control of Campylobacter jejuni biofilms in the food industry are being studied intensively. Natural products are promising alternative antimicrobial substances to control biofilm production, with particular emphasis on plant extracts. Dried flowers of Lavandula angustifolia were used to produce LEO, LEF, and LEW. The chemical compositions determined for these Lavandula preparations included seven major compounds that were selected for further testing. These were tested against C. jejuni, for biofilm degradation and removal. Next-generation sequencing was used to study the molecular mechanisms underlying LEO actions against C. jejuni adhesion and motility. Analysis of LEO revealed 1,8-cineol, linalool and linalyl acetate as the main components. For LEF and LEW, the main components were phenolic acid glycosides, with flavonoids rarely present. The minimal inhibitory concentrations of the Lavandula preparations and pure compounds against C. jejuni ranged from 0.2 mg/mL to 1 mg/mL. LEO showed the strongest biofilm degradation. The reduction of C. jejuni adhesion was by ≥1 log₁₀ CFU/mL, which satisfies European Food Safety Authority recommendations. Lavandula preparations reduced C. jejuni motility by almost 50%, which consequently can impact upon biofilm formation. These data are in line with the transcriptome analysis of C. jejuni, where LEO down-regulated genes important for biofilm formation. LEW also showed good antibacterial and anti-biofilm effects, particularly against adhesion and motility mechanisms. This defines an innovative approach using alternative strategies and novel targets to combat bacterial biofilm formation, and hence the potential to develop new effective agents with biofilm-degrading activities. Importance The Lavandula preparations used in this study are found to be effective against C. jejuni, a common foodborne pathogen. They show anti-biofilm properties at sub-inhibitory concentrations in terms of promoting biofilm degradation and inhibiting cell adhesion and motility, which are involved in the initial steps of biofilm formation. These results are confirmed by transcriptome analysis, which highlights the effect of Lavandula essential oil on C. jejuni biofilm properties. We show that the waste material from the hydrodistillation of Lavandula has particular anti-biofilm effects, suggesting that it may find reuse for industrial purposes. This study highlights the need for efforts directed towards such innovative approaches and alternative strategies against biofilm formation and maintenance by developing new naturally derived agents with anti-biofilm activities.

Protective Effect of Brassica napus L. Hydrosols against Inflammation Response in RAW 264.7 Cells

OBJECTIVE

To demonstrate the anti-inflammatory activity of Brassica napus L. hydrosols (BNH) in lipopolysaccharide (LPS)-stimulated RAW 264.7 cells.

METHODS

Composition analysis of BNH was conducted via gas chromatography-mass spectrometry after BNH were extracted. The nitric oxide (NO) production was measured using the Griess assay. Prostaglandin E₂ (PGE₂) production was evaluated with enzyme-linked immunosorbent assay. The effects of BNH on LPS-induced pro-inflammatory enzymes including inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) were evaluated using Western blot analysis. Furthermore, phosphorylation of nuclear factor-kappa B (NF-κB) and nuclear translocation of NF-κB p65 were evaluated with Western blot analysis and immunofluorescence staining, respectively.

RESULTS

Compared with LPS-stimulated cells, BNH markedly decreased the generation of NO and PGE₂ in LPS-stimulated RAW 264.7 cells (P<0.01 or P<0.05). Moreover, BNH inhibited protein levels of iNOS and COX-2 (P<0.01). Phosphorylation of NF-κB and nuclear translocation of NF-κB p65 was significantly inhibited by BNH (P<0.01 or P<0.05).

CONCLUSION

The anti-inflammatory activities of BNH were mediated via blockage of the NF-κB signaling pathways in LPS-stimulated RAW 264.7 cells.

Reconsidering Hydrosols as Main Products of Aromatic Plants Manufactory: The Lavandin (Lavandula intermedia) Case Study in Tuscany

: The present work evaluates for the first time two Lavandin (Lavandula × intermedia Emeric ex Loisel.) aromatic waters obtained from different plant organs, the flowers and the stems. Both extracts were analysed by GC-MS, which indicates semi-quantitative differences between the major metabolites including linalool, 1,8-cineole, camphor, linalyl acetate and 4-terpineol. ¹H-NMR and LC-MS investigation confirmed the presence of these compounds. Moreover, behavioural tests with the food insect pest Tribolium confusum (Coleoptera Tenebrionidae) showed a good repellency for both hydrosols extracts with RD₅₀ values of 3.6 and 3.3 µL cm^-2 for the flowers and stems, respectively; at the higher concentrations, however, the hydrosol extract from the flowers is expected to be more effective than the one from the stems. The effect of the flowers and stems aromatic water of Lavandin on seed germination of Raphanus sativus was also evaluated. Results showed that seed germination was completely inhibited by flowers hydrolate, having a possible application as natural herbicide. The overall experience with these Lavandin extracts indicates the potential of improved hydrolates to become the main distillation products, rather than by-products, of the aromatic plants manufacturing; this stimulates further discussions about the potential positive impacts that such a shift could have in the context of ecopharmacognosy.

Evaluation of antimicrobial activity of the hydrolate of Coridothymus capitatus (L.) Reichenb. fil. (Lamiaceae) alone and in combination with antimicrobial agents

Background

Hydrolates, complex mixtures containing traces of essential oils (EOs), are inexpensive, easy to make and less toxic than their corresponding EOs. The antibacterial and antifungal activity of the hydrolate of Coridothymus capitatus (L.) Reichenb. fil. (Lamiaceae) alone and in combination with antimicrobial drugs, such as tetracycline and itraconazole, were evaluated.

Methods

The chemical composition was analysed by gas-chromatography-mass spectrometry (GC-MS). Standard methods were performed to evaluate the susceptibility of some Gram-positive and Gram-negative bacteria, and Candida spp. to the hydrolate, in comparison with its EO. The hydrolate mechanism of action was assayed by propidium iodide and MitoTracker staining. Checkerboard tests were carried out for combinations studies.

Results

GC-MS identified 0.14% (v/v) of total EO content into hydrolate and carvacrol as a dominant component. The hydrolate showed a good antimicrobial activity against bacteria and yeasts. It exhibited a synergistic effect with itraconazole against Candida krusei, and an additive effect with tetracycline against methicillin-resistant Staphylococcus aureus strains. Hydrolate changed the membranes permeability of bacteria and yeasts and altered mitochondrial function of yeasts.

Conclusions

Our study extends the knowledge by exploiting non-conventional antimicrobial agents to fight the emergence of antibiotic resistance.

Chemical composition of hydrosol volatiles of flowers from ten Paeonia × suffruticosa Andr. cultivars from Luoyang, China

Hydrosol volatiles from flowers of ten Paeonia × suffruticosa Andr. cultivars were analysed by gas chromatography-mass spectrometry (GC-MS) and GC-flame ionisation detector (GC-FID) for the first time. Fifty components were identified representing 97.6-99.8% of total composition, in which oxygenated compounds (87.4-99.8%) predominated. Hydrosol volatiles of five and two cultivars presented chemotypes of 2-phenylethanol (48.0-79.5%) and 1,3,5-trimethoxybenzene (72.8%, 50.2%), respectively. Hydrosol volatiles of 'XYTH' rich in β-citronellol (57.2%) probably represented a newly defined chemotype with β-citronellol percentage over 50%. 'GFCC' hydrosol volatiles presented a balanced profile with 1,3,5-trimethoxybenzene (31.9%), β-citronellol (31.5%) and 2-phenylethanol (23.0%). 'LHZL' hydrosol volatiles were distinct from others due to occurrence of 6,9-heptadecadiene (2.0%), 2-heptanol (1.8%), pentadecane (1.5%), (Z)-3-nonen-1-ol (1.1%) and geraniol (15.7%). Chemotype characterisation of P. × suffruticosa Andr. hydrosols was of significance considering numerous cultivars of the species and potential applications of the hydrosols.

Determination of Various Drying Methods' Impact on Odour Quality of True Lavender (Lavandula angustifolia Mill.) Flowers

True lavender flowers (Lavandula angustifolia Mill.) is a critical source of essential oils and a flavouring agent used in numerous industries like foods, cosmetics and pharmaceuticals. Its main volatile constituents are linalool and linalyl acetate, which are commonly considered as main odour-active constituents (OACs). Nevertheless, the quality of true lavender flowers is highly dependent on its post-harvest treatment, mainly the preservation method. Recognising that drying is the most frequently used preservation method, the influence of various drying methods, including convective drying (CD) at 50, 60 and 70 °C, vacuum-microwave drying (VMD) with powers 240, 360 and 480 W and combined convective pre-drying at 60 °C followed by vacuum-microwave finish-drying with power 480 W (CPD-VMFD), on the quality of true lavender flowers was verified. The evaluation of influence was carried out by HS-SPME(HS, solid-phase microextraction), GC-MS, GC-MS-O (gas chromatography–mass spectrometry–olfactometry) techniques. Moreover, the sensory panel has assessed the sample odour quality. As a result, the optimal drying methods regarding the requirements for products were established. Overall, for total essential oil recovery, CD at 50 °C is the optimal drying method, while for odour quality concerning the sensory panel evaluation, VMD with power 360 W combined CPD-VMFD and CD at 50 °C is the optimal drying method.

Phytotoxic Effects of Commercial Eucalyptus citriodora, Lavandula angustifolia, and Pinus sylvestris Essential Oils on Weeds, Crops, and Invasive Species

Background: essential oils are well known for their pharmacological effectiveness as well as their repellent, insecticide, and herbicide activities. The emergence of resistant weeds, due to the overuse of synthetic herbicides, makes it necessary to find natural alternatives for weed control. The aim of this study was to evaluate the phytotoxic effects of Eucalyptus citriodora, Lavandulaangustifolia, and Pinus sylvestris, three common commercial essential oils, on weeds (Portulaca oleracea, Lolium multiflorum, and Echinochloa crus-galli), food crops (tomato and cucumber), and the invasive species Nicotiana glauca. Methods: to determine herbicidal effects, essential oils were tested at different concentrations (0.125–1 µL/mL). The index of germination and seedling length data were recorded over 14 days. Results: the in vitro assays showed that L. angustifolia with linalool (38.7 ± 0.1%), 1,8-cineole (26.5 ± 0.1%), and camphor (14.2 ± 0.1%) as the main compounds showed the most phytotoxic effects affecting seed germination in weeds and tomato, and the aforementioned invasive species. L. multiflorum was the most sensitive weed, particularly to lavender essential oil, which decreased the growth of its hypocotyl and radicle by 87.8% and 76.7%, respectively, at a dose of 1 µL/mL. Cucumber was the most resistant food crop, with no significant reduction observed in seed germination and hypocotyl growth with E. citriodora and L. angustifolia essential oils. Conclusions: lavender essential oil represents a promising candidate for the development of effective and safe herbicides in the management of L. multiflorum affecting cucumber crops.

Ecotoxicity of a novel biopesticide from Artemisia absinthium on non-target aquatic organisms

Biopesticides are increasingly being used to replace synthetic pesticides for pest control. This change raises concern for its environmental impacts, especially on non-target organisms. In this study, the ecotoxicological effects of a potential nematicide from Spanish populations of Artemisia absinthium (var. Candial) were evaluated on freshwater and aquatic non-target organisms. The study focused on the aqueous extract (hydrolate), the principal component of which ((-) -(Z) -2,6-dimethylocta-5,7-diene-2,3-diol) is responsible for its nematicidal effect. Until now, the hydrolate has been considered a byproduct of the process used to obtain essential oils, and there are no studies on its ecotoxicity from any plant with biopesticide properties. Our results indicated that A. absinthium hydrolate caused acute toxicity for non-target organisms at dilutions as low as 0.2%. The sensitivity of the organisms, from the most to the least sensitive, was: Daphnia magna (LC₅₀ = 0,236%) > Vibrio fisheri (LC₅₀ = 1,85%) > Chlamydomonas reinhardtii (LC₅₀ = 16,49). Moreover, the A. absinthium organic extract was highly toxic to D. magna (LC₅₀ = 0,093 mg/L). A. absinthium hydrolate toxicity was also tested on a natural river microbial community. Bacterial growth was not affected; the physiology of the community was only slightly modified, namely through an increased ability to degrade different substrates, mainly carbohydrates. This study provides for the first time an exhaustive assessment of the environmental exposure of a plant-derived biopesticide and shows that these products may cause a broad range of toxicity on non-target aquatic organisms.

Lavandula Essential Oils: A Current Review of Applications in Medicinal, Food, and Cosmetic Industries of Lavender

The global essential oil market has been steadily increasing in size over the past few years, and is estimated to reach ca. $7.5 billion USD per annum by 2018. Lavenders ( Lavandula; Lamiaceae) contribute significantly to this market, yielding ca. 1500 tons of essential oils which are primarily used in cosmetics, personal care products, and medicines. Recent literature indicates that these oils may also have applications in food preservation and pest control, among others. The medicinal and pharmaceutical properties of lavenders are chiefly due their essential oils, in particular the major essential oil constituents linalool and linalyl acetate, although certain activities have been attributed to the phenolic compounds. In addition, there is evidence that the major and minor essential oil constituents act synergistically to provide various biological effects. A substantial amount of current research focuses on evaluating the biological activities of lavender essential oils for potential use in traditional and complementary medicine, food systems, cosmetic and fragrance formulations, and insect control products. This review examines recent progress in these areas, and highlights the current and future implications for these economically and medicinally valuable plants.

Concentration of natural aroma compounds from fruit juice hydrolates by pervaporation in laboratory and semi-technical scale. Part 1. Base study

The first article of a two-article series presents pervaporation (PV) of volatile aroma compounds from fruit juice hydrolates (plum, apple, blackcurrant and cherry). The purpose of this research was to evaluate the effectiveness of fruit juice hydrolates separation on a laboratory scale (inert gas flow pervaporation system) and semi-technical (vacuum pervaporation system) by means of pervaporation. To create precise matrices for hydrolates before and after pervaporation for each of the separated systems, solid phase microextraction (SPME) technique and the gas chromatography-mass spectrometry (GC-MS) was applied. Sensory analysis confirmed improvement of aroma note of concentrated permeates as compared to feed hydrolates solutions. The results indicated that pervaporation may be applied in condensing aromatic water or fruit juice hydrolate, which may significantly enhance product quality and lengthen shelf life.

Comparison of the therapeutic effect of the Persian Medicine Protocol with the common treatment of chronic rhinosinusitis: a randomized clinical trial

Background

Chronic rhinosinusitis is one of the most common diseases affecting the quality of life of patients. Patients suffer from high costs in the diagnosis and treatment of the disease. Frequent recurrence and failure of therapeutic protocols are among the most important issues in the management of this disease. In view of this, the use of traditional and complementary therapies to promote the treatment of this disease has been increasingly taken into account.

Objective

Comparison of the effectiveness of the Persian Medicine Protocol with the conventional therapy in the treatment of chronic rhinosinusitis.

Methods

A randomized clinical trial was conducted at Imam Reza Hospital in Mashhad, Iran from July 2016 to March 2017. For patients with chronic rhinosinusitis symptoms, endoscopy of the sinuses was performed by an ENT specialist and in the case of negative endoscopy, paranasal sinus CT scan was requested. A total of 42 patients with chronic rhinosinusitis were randomly assigned to two groups. The first group (classical) received systemic and intranasal cortisone, and the second group (traditional) received a therapeutic Persian medicine protocol including intranasal lavender oil, and Liquorice Marjoram Tea (L. M. tea) for six weeks. The symptoms of the patients were evaluated using the SNOT-22 questionnaire at the beginning of the study and at the sixth week. If no improvement occurs, treatment continued for 12 weeks. Data were analyzed by SPSS version 16, using ANOVA, independent-samples and paired-samples t-test, Wilcoxon signed-rank test, and simple linear regression.

Results

In 20 patients in the traditional group, the decrease in SNOT score was observed as 56% after 6 weeks treatment (p=0.001), which is similar to the effect of the first group (classical). Although there was no statically significant difference between the two groups, in clinical terms, the difference in mean systemic symptoms such as confusion with 1.05 (p=0.5) and fatigue with 1.63 (p=0.01) had more improvement in the traditional group, and the difference in mean local symptoms such as nasal congestion with 2.37 (p=0.78) and runny nose with 1.95 (p=0.14) had a more decrease in the classical group.

Conclusion

The results of this trial indicate the effectiveness of the Persian Medicine Protocol (including Lavender oil and L.M tea) in the treatment of chronic rhinosinusitis, especially on improving systemic symptoms. Nevertheless more clinical studies are necessary to support the acquired results.

Trial registration

This trial was registered at the Iranian Center for Clinical Trials (ID: IRCT2015112425217N1).

Funding

This research is part of a PhD thesis and is funded by the Vice-Chancellor for Research at Mashhad University of Medical Sciences, Grant No. 931673.

Essential oil obtained from micropropagated lavender, its effect on HSF cells and application in cosmetic emulsion as a natural protective substance

The aim of the study was to determine the influence of the essential oils isolated from the field - grown and micropropagated in vitro narrow - leaved lavender of the 'Munstead' cultivar, on human skin cells, and their capability to synthesise procollagen. The amount of procollagen type I produced by fibroblast cells was determined using ELISA kit. Essential oil isolated from micropropagated lavender was further used as a protective ingredient against the development of microorganisms in O/W cosmetic emulsion. The presented results demonstrate that the use of 0.01, 0.001 and 0.0001% essential oils isolated from in vitro plants stimulate HSF cells to the production of procollagen. It was further performed that the tested essential oil used in the concentration of 0.1% in a cosmetic emulsion is characterised by preservative effect for cosmetic preparations for the period of 3 months.

Comparison of phenolic acids and flavonoids contents in various cultivars and parts of common lavender (Lavandula angustifolia) derived from Poland

The aim of study was to compare the content of phenolic acids and flavonoids in two cultivars of Lavandula angustifolia: 'Blue River' and 'Ellagance Purple', including flowers and leafy stalks. Total phenolics and total flavonoids contents were determined by UV-Vis spectroscopy. The contents of total phenolics in leafy stalks (3.71-4.06 mg g^-1 d.m.) were higher than in flowers (1.13-1.14 mg g^-1 d.m.). Similarly, higher total contents of flavonoids were determined in leafy stalks (3.41-3.51 mg g^-1 d.m.), as compared with flowers (0.86-0.91 mg g^-1 d.m.). Phenolic acids and flavonoids were identified and quantified using HPLC and UPLC methods. Three phenolic acids were determined: rosmarinic, ferulic and caffeic acid. Lavender extracts contained also flavonoids from group of apigenin, luteolin and quercetin. Higher amounts of luteolin diglucuronide and luteolin glucuronide were found in leafy stalks in comparison to flowers. Obtained results indicate that leafy stalks of lavender can be also valuable source of antioxidant compounds.

Anti-inflammatory activity of hydrosols from Tetragonia tetragonoides in LPS-induced RAW 264.7 cells

The present study was performed to investigate the anti-inflammatory activity of Tetragonia tetragonoides hydrosols (TTH) and its underlying mechanism in lipopolysaccharide (LPS)-induced RAW 264.7 cells. Gas chromatography (GC) coupled with mass spectrometry and retention index calculations showed that TTH were mainly composed of tetratetracontane (29.5 %), nonacosane (27.6 %), and oleamide (17.1 %). TTH significantly decreased the production of nitric oxide (NO), prostaglandin E2 (PGE₂), interleukin (IL)-6, and IL-1β in LPS-stimulated RAW 264.7 cells. Consistent with these observations, TTH treatment decreased the protein expression levels of inducible NO synthase (iNOS) and cyclooxygenase-2 (COX-2). The molecular mechanism of its anti-inflammatory activity was found to be associated with inhibition of nuclear factor-kappa B (NF-κB) phosphorylation and nuclear translocation of NF-κB 65. Furthermore, TTH markedly suppressed the LPS-induced phosphorylation of mitogen-activated protein kinases (MAPKs). Taken together, these data indicate that TTH exerts an anti-inflammatory activity by inhibiting the NF-κB and MAPK signaling pathways in LPS-stimulated RAW 264.7 cells.

Change in Caco-2 cells following treatment with various lavender essential oils

Lavender is an aromatic evergreen shrub diffused in the Mediterranean basin appreciated since antiquity. The genus Lavandula is part of Lamiaceae family and includes more than 20 species, among which true lavender (L. vera D.C. or L. angustifolia Miller.) and spike lavender (L. latifolia Medikus); there are also numerous hybrids known as lavandins (L. hybrida Rev.). L. vera, spike lavender and several hybrids are the most intensely used breeding species for the production of essential oils. Lavender and lavandin essential oils have been applied in food, pharmaceutical and other agro industries as biological products. In their chemical composition, terpenes linalool and linalyl acetate along with terpenoids such as 1,8-cineole are mostly responsible for biological and therapeutic activities. This study evaluates cytotoxic activity of essential oils derived from four lavender species on human epithelial colorectal adenocarcinoma cells. Analysis of pre- and post-treatment cell morphology has been performed using scanning electron microscope.

Three new phenylpropanoids from Lavandula angustifolia and their bioactivities

Three new phenylpropanoids, 3-(3,4-dimethoxy-5-methylphenyl)-3-oxopropyl acetate (1), 3-hydroxy-1-(3,4-dimethoxy-5-methylphenyl)propan-1-one (2), and 3-hydroxy-1-(4-methylbenzo[d][1,3]dioxol-6-yl) propan-1-one (3), together with three known phenylpropanoids (4-6) were isolated from the whole plant of Lavandula angustifolia. Their structures were determined by means of HRESIMS and extensive 1D and 2D NMR spectroscopic studies. Compounds 1-6 were tested for their anti-tobacoo mosaic virus (TMV) activities and cytotoxicity activities. The results revealed that compounds 1-3 showed high anti-TMV activity with inhibition rate of 35.2, 38.4 and 33.9%. These rates are higher than that of positive control. The other compounds also showed potential anti-TMV activities with inhibition rates in the range of 26.8-28.9%, respectively. Compounds 1-6 also showed weak inhibitory activities against some tested human tumour cell lines with IC50 values in the range of 3.8-8.8 μM.

Oxygenated monoterpenes-rich volatile oils as potential antifungal agents for dermatophytes

Essential oils (EOs) extracted from Lavandula luisieri and Cymbopogon citratus were tested for their antifungal activity against ten clinical isolates of dermatophytes isolated from cases of tinea pedis. Inhibition of conidial germination and antifungal drug/EO combination assay were tested on two ATCC reference strains of Trichophyton rubrum and Trichophyton mentagrophytes. EOs were characterised by high amount of oxygenated monoterpenes in their composition. Strong antifungal activity was observed for the majority of clinical strains, and fungicidal activity was demonstrated. Positive interaction between L. luisieri EO combined with terbinafine was observed against terbinafine-resistant strain (Tr ATCC MYA-4438). Significative reduction of the germination was observed above 100 μg mL^-1. Both oils were safe to macrophage mammalian cells at tested concentration. This study describes the antifungal activity of L. luisieri and C. citratus EOs against dermatophytes, which could be useful in designing new formulations for topical treatments.