Regulation of gene transcription in Escherichia coli O157:H7 in response to a natural derivate peptide of esculentin-1a used in combination with essential oils from plants of the Cymbopogon genus.

INTRODUCTION: We analyzed the expression of several genes implicated in the pathogenicity of Escherichia coli O157:H7, treating bacteria with Esc(1-21), a derivative of peptide esculentin-1 in combination with three essential oils obtained from plants from the Cympopogon genus. METHODS: We used the checkerboard assay to determine the antimicrobial activity of the combinations. We analyzed the expression of some genes implicated in the pathogenicity and quorum sensing system of E. coli O157:H7 by real-time RT-PCR technique. RESULTS: Treatment of the bacteria with the peptide combined with oils had an efficacious antimicrobial activity. The analysis of gene expression showed that all used combinations regulate positively the espAD and ler genes, located in the pathogenicity island, named the locus of enterocyte effacement. None of the combinations affects the quorum sensing genes: lsrABCFKR and qseBC. CONCLUSIONS: This study demonstrates that the use of essential oil/peptide combinations can be effective in fighting microbial infections.

Amoebicidal activity of essential oils and essential oil-based microemulsions of Aloysia citrodora Ortega ex Pers., Cymbopogon winterianus Jowitt ex Bor, and Ocimum gratissimum L. against Acanthamoeba polyphaga trophozoites.

AIMS: Evaluate the in vitro efficacy of the essential oils derived from Aloysia citrodora (Verbenaceae), Cymbopogon winterianus (Poaceae), and Ocimum gratissimum (Lamiaceae) against Acanthamoeba polyphaga trophozoites. Additionally, microemulsions formulated with these essential oils, along with their major components, were analyzed. METHODS AND RESULTS: The prepared microemulsions were characterized using polarized light microscopy and rheological techniques. The amoebicidal activity was determined by measuring the inhibitory concentration (IC50). Flow cytometry was employed to detect membrane damage and alterations in trophozoites size. The results revealed transparent and thermodynamically stable microemulsions. The essential oil from O. gratissimum exhibited a lower IC50, with values of 280.66 and 47.28 µg ml-1 after 24 and 48 h, respectively. When microemulsions containing essential oils were tested, the IC50 values exhibited a reduction of over 80% after 24 h. Particularly, eugenol, a constituent of the O. gratissimum essential oil, displayed higher amoebicidal activity. The essential oils also caused damage to the cell membrane, resulting in the subsequent death of the trophozoites. CONCLUSIONS: The EOs of A. citrodora, C. winterianus, and O. gratissimum and their microemulsions showed antiparasitic effect against A. polyphaga trophozoites, representing promising alternatives for the treatment of diseases caused by this protozoan.

Exploring the Bioactive Potential of Moroccan Lemon Grass (Cymbopogon citratus L.): Investigations on Molecular Weight Distribution and Antioxidant and Antimicrobial Potentials.

Research on lemon grass (Cymbopogon citratus L.) revealed a variety of active molecules and examined their biological characteristics. However, most of these studies were conducted on wild varieties, while cultivated plants were addressed less. This study aimed to characterize the biomolecules and biological activities of lemon grass growing under North African conditions in Morocco. Phenolic compound profiles of aqueous (AE), ethanol (EE), and methanol (ME) extracts and their fractions were obtained with steric exclusion chromatography on Sephadex G50 gel and identified by LC-MS/MS. Then, total polyphenols (TPC), flavonoids (TFC), and antioxidant activities (FRAP: scavenging value and TAC: Total Antioxidant Capacity) of the fraction were evaluated, as well as the antimicrobial activity. The obtained results showed that the ME contained eight major compounds (i.e., apigenine-7-O-rutinoside and myricitine-3-O-rutinoside). The AE showed the presence of five molecules (i.e., kaempferol-3-O-glucuronide), while EE showed the presence of three molecules (i.e., quercetine-3-O-rutinoside). Regarding the chemical characterization, the highest value of total phenolic content (TPC) was obtained in AE (25) (4.60 ± 0.29 mg/g), and the highest value of total flavonoid content (TFC) was obtained in ME (29) (0.7 ± 0.08 mg/g). Concerning the antioxidant activity, the highest FRAP was obtained in ME (29) (97.89%), and the highest total antioxidant capacity (TAC) was obtained in ME (29) (89.89%). Correlation between FRAP, TPC, and TFC was noted only in fractions of AE and ME. All tested extracts of C. citratus and their fractions showed a significant antimicrobial effect. The lowest minimum inhibitory concentration (MIC) was recorded for ME against E. coli. Extracts' biological activities and their fractions were governed by their active molecules. These data are new and clarify a novel aspect of bioactive molecules in the extracts of cultivated C. citratus. Equally, throughout this research, we clarified the relationship between identified molecules and their biological properties, including antioxidant and anti-microbial activities, which is new for the study area. This study is suggested as a reference for comparative studies and other assays of other biological activities for the study plant.

Lemongrass essential oil and its major component citronellol: evaluation of larvicidal activity and acetylcholinesterase inhibition against Anopheles sinensis.

Mosquito-borne diseases, such as malaria, dengue fever, and the Zika virus, pose significant global health challenges, affecting millions annually. Due to increasing insecticide resistance, there is a growing interest in natural alternatives for mosquito control. Lemongrass essential oil, derived from Cymbopogon citratus, has shown promising repellent and larvicidal properties against various mosquito species. In this study, we investigated the larvicidal effect of lemongrass oil and its major compounds on Anopheles sinensis, the primary malaria vector in China. GC-MS analysis identified the major compounds of lemongrass oil as ( +)-citronellal (35.60%), geraniol (21.84%), and citronellol (13.88%). Lemongrass oil showed larvicidal activity against An. sinensis larvae, with an LC50 value of 119.20 ± 3.81 mg/L. Among the major components, citronellol had the lowest LC50 value of 42.76 ± 3.18 mg/L. Moreover, citronellol demonstrated inhibitory effects on acetylcholinesterase (AChE) activity in An. sinensis larvae, assessed by homogenizing larvae at different time points following treatment. Molecular docking studies further elucidated the interaction between citronellol and AChE, revealing the formation of hydrogen bonds and Pi-Sigma bonds. Aromatic amino acid residues such as Tyr71, Trp83, Tyr370, and Tyr374 played a pivotal role in these interactions. These findings may contribute to understanding lemongrass oil's larvicidal activity against An. sinensis and the mechanisms underlying these effects.

Antifungal, molecular docking and cytotoxic effect of the essential oil of Cymbopogon citratus (DC) Stapf. and Cymbopogon nardus (L.) Rendle against Candida albicans.

Brazil is renowned for its extensive plant biodiversity, with emphasis on Cymbopogon, C. citratus and C. nardus, with broad antimicrobial potential. Candidemias caused by Candida albicans are highly prevalent in immunosuppressed individuals and are associated with infections by biofilms on medical devices. The aim of this study was to evaluate the antimicrobial potential of essential oils C. citratus and C. nardus against C. albicans in planktonic and biofilm forms. Essential oils were obtained by hydrodistillation and chemical composition evaluated by GC-FID and GC-MS. The minimum inhibitory concentration was determined by the broth microdilution method and the synergy effect of essential oils and amphotericin B were evaluated by the checkerboard test. Biofilm activity was determined by the XTT assay. Cytotoxicity assays performed with VERO cells and molecular docking were performed to predict the effect of oil interaction on the SAP-5 enzyme site. The results showed activity of essential oils against planktonic cells and biofilm of C. albicans. Furthermore, the oils had a synergistic effect, and low cytotoxicity. Molecular docking showed interaction between Cadinene, Caryophyllen oxide, Germacrene D with SAP-5. The results indicate that Cymbopogon spp. studied are anti-Candida, with potential for further application in therapy against infections caused by C. albicans.

Divergent Roles of the Auxin Response Factors in Lemongrass (Cymbopogon flexuosus (Nees ex Steud.) W. Watson) during Plant Growth.

Auxin Response Factors (ARFs) make up a plant-specific transcription factor family that mainly couples perception of the phytohormone, auxin, and gene expression programs and plays an important and multi-faceted role during plant growth and development. Lemongrass (Cymbopogon flexuosus) is a representative Cymbopogon species widely used in gardening, beverages, fragrances, traditional medicine, and heavy metal phytoremediation. Biomass yield is an important trait for several agro-economic purposes of lemongrass, such as landscaping, essential oil production, and phytoremediation. Therefore, we performed gene mining of CfARFs and identified 26 and 27 CfARF-encoding genes in each of the haplotype genomes of lemongrass, respectively. Phylogenetic and domain architecture analyses showed that CfARFs can be divided into four groups, among which groups 1, 2, and 3 correspond to activator, repressor, and ETTN-like ARFs, respectively. To identify the CfARFs that may play major roles during the growth of lemongrass plants, RNA-seq was performed on three tissues (leaf, stem, and root) and four developmental stages (3-leaf, 4-leaf, 5-leaf. and mature stages). The expression profiling of CfARFs identified several highly expressed activator and repressor CfARFs and three CfARFs (CfARF3, 18, and 35) with gradually increased levels during leaf growth. Haplotype-resolved transcriptome analysis revealed that biallelic expression dominance is frequent among CfARFs and contributes to their gene expression patterns. In addition, co-expression network analysis identified the modules enriched with CfARFs. By establishing orthologous relationships among CfARFs, sorghum ARFs, and maize ARFs, we showed that CfARFs were mainly expanded by whole-genome duplications, and that the duplicated CfARFs might have been divergent due to differential expression and variations in domains and motifs. Our work provides a detailed catalog of CfARFs in lemongrass, representing a first step toward characterizing CfARF functions, and may be useful in molecular breeding to enhance lemongrass plant growth.

Larvicidal activity of ß-Citral: An In-vitro and In-silico study to understand its potential against mosquito.

Tropical and subtropical regions face millions of deaths from mosquito-borne illnesses yearly. Insecticides prevent transmission but pose health risks like dermatitis and allergies. The primary objective was to mitigate the recurring dependence on synthetic insecticides, thereby curbing the development of mosquito resistance. Leaves of Cymbopogon flexuosus (lemongrass) was collected from Mayurbhanj, India, processed, then extracted by steam distillation for essential oils & analyzed spectroscopically. Larvicidal assays were performed across varying concentrations, revealing the significant mortality induced by the Cymbopogon flexuosus extract against Anopheles stephensi larvae. 3D structure was modelled by using G protein-coupled receptors (GPCR) sequence and structural stability was also validated. After docking the binding free energy was determined from GPCR protein with ß-citral complex. Molecular dynamics (MD) study was conducted on the docked pose that displayed an optimal interactome profile. The larvicidal assay at the 12th and 24th hour revealed the highest LC50 (lethal concentration) of 23.493 ppm and 19.664 ppm . ß-Citral has a high binding affinity and an identifiable binding site, which suggests that it may play a larvicidal role in regulating the receptor's function by creating stable complexes with it. ß-Citral from lemongrass oils has potential larvicidal activity and effective against GPCR family 1 of mosquito and highly effective repellents against mosquito-borne diseases.

Acaricidal potential of essential oils on Rhipicephalus linnaei: Alternatives and prospects.

The acaricidal potential of various essential oils (EOs) has been evaluated based on their benefits in tick control. This study aimed to investigate the tick-killing activity of Pogostemon cablin "patchouli," Cymbopogon martinii "palmarosa," and Cymbopogon flexuosus "lemongrass" EOs on Rhipicephalus linnaei. Engorged females were collected from domiciled and non-domiciled dogs from Jataí city, Goiás state, to obtain larvae and nymphs in a controlled environment. Two commercial EOs brands were used in this study in different EOs concentrations (2.5, 5, 10, and 20 mg/mL), and was tested by immersion of larvae and nymphs. In the in vitro evaluation of EOs toxicity against R. linnaei larvae, 100 % mortality was achieved with 10 mg/mL of P. cablin oil, whereas mortality rates greater than 98 % were observed with 20 mg/mL of C. martinii and C. flexuosus. In nymphs, high sensitivity was observed, with 100 % mortality achieved using 5 mg/mL of P. cablin and 20 mg/mL of C. martinii and C. flexuosus. The EO of P. cablin "patchouli" demonstrated in vitro toxicity at a lower concentration than the other oils in the two development stages of R. linnaei, and was considered the most efficient and with verified acaricidal activity. Oils of C. martinii "palmarosa" and C. flexuosus "lemongrass" achieved mortality greater than 95 % in larvae and nymphs only at the highest concentration. Therefore, the acaricidal effects of the tested EOs are promising, especially of patchouli oil, which promoted high mortality at a low concentration (LC90 of 2.21 mg/mL).

The antioxidant and antimicrobial activity of ethanolic extract in roots, stems, and leaves of three commercial Cymbopogon species.

BACKGROUND: Cymbopogon is a member of the family Poaceae and has been explored for its phytochemicals and bioactivities. Although the antimicrobial activities of Cymbopogon spp. extracts have been extensively studied, comprehensive analyses are required to identify promising compounds for the treatment of antimicrobial resistance. Therefore, this study investigated the antioxidant and antimicrobial properties of Cymbopogon spp. ethanolic extracts in every single organ. METHODS: Ethanolic extracts were obtained from three Indonesian commercial species of Cymbopogon spp., namely Cymbopogon citratus (L.) Rendle, Cymbopogon nardus (DC.) Spatf., and Cymbopogon winterianus Jowitt. The leaf, stem, and root extracts were evaluated via metabolite profiling using gas chromatography-mass spectrometry (GC-MS). In silico and in vitro analyses were used to evaluate the antioxidant and antimicrobial properties of the Cymbopogon spp. ethanolic extracts. In addition, bioactivity was measured using cytotoxicity assays. Antioxidant assays were performed using 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2-azino-bis [3-ethylbenzothiazoline-6-sulfonic acid (ABTS) to determine toxicity to Huh7it-1 cells using a tetrazolium bromide (MTT) assay. Finally, the antimicrobial activity of these extracts was evaluated against Candida albicans, Bacillus subtilis, Staphylococcus aureus, and Escherichia coli using a well diffusion assay. RESULTS: GC-MS analysis revealed 53 metabolites. Of these, 2,5-bis(1,1-dimethylethyl)- phenol (27.87%), alpha-cadinol (26.76%), and 1,2-dimethoxy-4-(1-propenyl)-benzene (20.56%) were the predominant compounds. C. winterianus and C. nardus leaves exhibited the highest antioxidant activity against DPPH and ABTS, respectively. Contrastingly, the MTT assay showed low cytotoxicity. C. nardus leaf extract exhibited the highest antimicrobial activity against E. coli and S. aureus, whereas C. winterianus stem extract showed the highest activity against B. substilis. Furthermore, computational pathway analysis predicted that antimicrobial activity mechanisms were related to antioxidant activity. CONCLUSIONS: These findings demonstrate that the leaves had strong antioxidant activity, whereas both the leaves and stems showed great antimicrobial activity. Furthermore, all Cymbopogon spp. ethanolic extracts showed low toxicity. These findings provide a foundation for future studies that assess the clinical safety of Cymbopogon spp. as novel drug candidates.

Toxicity of 6-gingerol and Cymbopogon citratus against Pediculus humanus capitis De Geer (Phthiraptera: Pediculidae): Mortality, detoxifying enzymes, and morphological ultrastructure alterations in lice.

Pediculus humanus capitis (head louse), which causes pediculosis capitis, remains a global health concern. Plant products are efficient alternative pediculicides for treating the human ectoparasite P. h. capitis which is resistant to permethrin. The study evaluates the toxicity and mechanisms of 6-gingerol and Cymbopogon citratus leaf extract on P. h. capitis. Pediculus humanus capitis adult stages were exposed to three different dosages of 6-gingerol and C. citratus crude leaf extract on filter sheets for 5, 10, and 30 min, respectively. The biochemical approach was used to assess the activity of detoxifying enzymes including acetylcholinesterase (AChE), glutathione S-transferase (GST), and oxidase. Scanning electron microscope (SEM) was used to investigate the ultrastructure of the morphological body of lice. After 30 min, 6-gingerol and C. citratus leaf extract killed P. h. capitis completely. Bioassay periods significantly affected lice mortality (P < 0.05). The LC50 values for 6-gingerol and C. citratus extract were 1.79 µg/cm2 and 25.0 µg/cm2, respectively. 6-Gingerol and C. citratus leaf extract significantly lower AChE and GST activity (P < 0.05). Cymbopogon citratus also caused morphological ultrastructure changes in P. h. capitis, including an irregularly formed head, thorax, abdominal respiratory spiracles, and belly. 6-Gingerol and C. citratus leaf extracts could be used as an alternate pediculicide to decrease P. h. capitis populations.

Effect of Cymbopogon olivieri-based herbal vaginal product on bacterial vaginosis.

OBJECTIVE: Bacterial vaginosis is the most common vaginal infection in reproductive-age women. If it is not treated, the quality of life will be reduced. In this study, the herbal medicine product Cymbopogon olivieri was used for its treatment. METHODS: This study was conducted with 90 women. The patients were randomly divided into two groups of 45: Cymbopogon olivieri and metronidazole. The treatment period was 7 days for each group. Improvement status was determined by eliminating at least three out of four of Amsel's criteria. A new variable with two order levels (negative and positive) was constructed. This new variable shows the status of the treatment process. Chi-square and Fisher's exact tests were used to examine the relationship between the new variable and treatment status. RESULTS: The results demonstrate that Cymbopogon olivieri and metronidazole significantly reduced the burning, itching, malodor, abnormal vaginal discharge, pH, clue cell, and positive whiff test (p<0.05). The findings also demonstrate that neither treatment was statistically different from the other for at least three of Amsel's criteria. CONCLUSION: This study shows that the effect of Cymbopogon olivieri on bacterial vaginosis is similar to that of metronidazole. Hence, Cymbopogon olivieri is a suitable option to treat bacterial vaginosis.

Comparative evaluation of biodegradation of chlorpyrifos by various bacterial strains: Kinetics and pathway elucidation.

The present study focused on the isolation and identification of CP and TCP bacteria degrading bacteria from the rhizospheric zone of aromatic grasses i.e. palmarosa (Cymbopogon martinii (Roxb. Wats), lemongrass (Cymbopogon flexuosus) and vetiver (Chrysopogon zizaniodes (L.) Nash.). So that these isolates alone or in combination with the vegetation of aromatic grasses will be used to clean up CP-contaminated soils. The study also explored enzymatic activities, CO2 release, dechlorination potential, and degradation pathways of bacterial strains. A total of 53 CP-tolerant bacteria were isolated on their physical characteristics and their ability to degrade CP. The ten highly CP-tolerant isolates were Pseudomonas aeruginosa Pa608, three strains of Pseudomonas hibiscicola R4-721 from different rhizosphere, Enterococcus lectis PP2a, Pseudomonas monteilii NBFPALD_RAS131, Enterobacter cloacae L3, Stenotrophomonas maltophilia PEG-390, Escherichia coli ABRL132, and Escherichia coli O104:H4 strain FWSEC0009. The CO2 emission and phosphatase activities of the isolates varied from 3.1 to 8.6 µmol mL-1 and 12.3 to 31 µmol PNP h-1, respectively in the CP medium. The degradation kinetics of CP by these isolates followed a one-phase decay model with a dissipation rate ranging from 0.048 to 0.41 d-1 and a half-life of 1.7-14.3 days. The growth data fitted in the SGompertz equation showed a growth rate (K) of 0.21 ± 0.28 to 0.91 ± 0.33 d-1. The P. monteilii strain had a faster growth rate while E. coli ABRL132 had slower growth among the isolates. The rate of TCP accumulation calculated by the SGompertz equation was 0.21 ± 0.02 to 1.18 ± 0.19 d-1. The Pseudomonas monteilii showed a lower accumulation rate of TCP. Among these, four highly effective isolates were Pseudomonas aeruginosa Pa608, Pseudomonas monteilii NBFPALD_RAS131, Stenotrophomonas maltophilia PEG-390, and Pseudomonas hibiscicola R4-721. Illustrations of the degradation pathways indicated that the difference in metabolic pathways of each isolate was associated with their growth rate, phosphatase, dehydrogenase, oxidase, and dechlorination activities.

Synergistic Interaction of Certain Essential Oils and Their Active Compounds with Fluconazole against Azole-resistant Strains of Cryptococcus neoformans.

OBJECTIVES: This study investigated the anti-cryptococcal potential of certain essential oils (EOs)/compounds alone and in combination with fluconazole. MATERIALS AND METHODS: We investigated the antifungal activity of oils of Cinnamomum verum, Cymbopogon citratus, Cymbopogon martini, and Syzygium aromaticum, and their major active ingredients cinnamaldehyde, citral, eugenol, and geraniol against clinical and standard strains of Cryptococcus neoformans (CN). Disc diffusion, broth microdilution, checkerboard methods, and transmission electron microscopy were employed to determine growth inhibition, synergistic interaction, and mechanism of action of test compounds. RESULTS: EOs/compounds showed pronounced antifungal efficacy against azole-resistant CN in the order of cinnamaldehyde > eugenol > S. aromaticum > C. verum > citral > C. citratus > geraniol ≥ C. martini, each exhibiting zone of inhibition >15 mm. These oils/compounds were highly cidal compared to fluconazole. Eugenol and cinnamaldehyde showed the strongest synergy with fluconazole against CN by lowering their MICs up to 32-fold. Transmission electron microscopy indicated damage of the fungal cell wall, cell membrane, and other endomembranous organelles. CONCLUSION: Test oils and their active compounds exhibited potential anti-cryptococcus activity against the azole-resistant strains of CN. Moreover, eugenol and cinnamaldehyde significantly potentiated the anti-cryptococcal activity of fluconazole. It is suggested that multiple sites of action from oils/compounds could turn static fluconazole into a cidal drug combination in combating cryptococcosis.

RésuméObjectifs: Cette étude a étudié le potentiel anti-cryptocoque de certaines huiles essentielles (HE)/composés seuls et en combinaison avec fluconazole. Matériels et méthodes: Nous avons étudié l'activité antifongique des huiles de Cinnamomum verum, Cymbopogon citratus, Cymbopogon martini et Syzygium spiceum , et leurs principaux ingrédients actifs, le cinnamaldéhyde, le citral, l'eugénol et le géraniol, contre les normes cliniques et standards. souches de Cryptococcus neoformans (CN). Diffusion sur disque, microdilution en bouillon, méthodes en damier et microscopie électronique à transmission ont été utilisés pour déterminer l'inhibition de la croissance, l'interaction synergique et le mécanisme d'action des composés testés. Résultats: HE/composés a montré une efficacité antifongique prononcée contre les CN résistantes aux azoles dans l'ordre suivant: cinnamaldéhyde > eugénol > S. spiceum > C. verum > citral > C. citratus > géraniol ≥ C. martini , chacun présentant une zone d'inhibition > 15 mm. Ces huiles/composés étaient hautement cides par rapport au fluconazole. L'eugénol et le cinnamaldéhyde ont montré la synergie la plus forte avec le fluconazole contre le CN en abaissant leurs CMI jusqu'à 32 fois. La microscopie électronique à transmission a indiqué des dommages à la paroi cellulaire fongique, à la membrane cellulaire et à d'autres organites endomembranaires. Conclusion: Les huiles testées et leurs composés actifs ont montré une activité anti-cryptocoque potentielle contre les souches de CN résistantes aux azoles. De plus, l'eugénol et le cinnamaldéhyde ont significativement potentialisé l'activité anticryptococcique du fluconazole. Il est suggéré que plusieurs Les sites d'action des huiles/composés pourraient transformer le fluconazole statique en une combinaison médicamenteuse cide pour lutter contre la cryptococcose.

Cross-talk between antioxidant production and secondary metabolite biosynthesis under combined effects of ozone stress and nitrogen amendments: A case study of lemongrass.

The present experiment was done to study the interactive effects of soil nitrogen (N) amendments and elevated ozone (O3) (N-O3) on a medicinal plant, lemongrass [Cymbopogon flexuosus (Steud.) (Wats.)]. The experiment used two doses of inorganic soil nitrogen (N1, recommended and N2, 1.5-times recommended dose) in open-top chambers under ambient and elevated (ambient + 15 ppb and ambient + 30 ppb) O3 conditions. To analyze various characteristics, samples were collected at 45 and 90 days after transplantation (DAT). Additionally, at 110 days after transplantation (DAT), the metabolite contents of the leaves and essential oils were analyzed. The present study aims to investigate the mechanistic approach involving the crosstalk between antioxidant production and secondary metabolite biosynthesis in lemongrass upon N-O3 interactions. The present experiment showed that N amendments can be an efficient measure to manage O3 injury in plants, along with ensuring a balance between primary and secondary metabolic pathways, thus sustaining the plant defense and production of bioactive compounds, simultaneously. Under N-O3, not only the Halliwell asada pathway was stimulated resulting in the increased activities and concentrations of antioxidant pools; the shikimate, phenylpropanoid and mevalonic acid pathways were also invigorated, producing more number and contents of secondary metabolites (SMs), compared with plants that were not treated with N doses. This study suggests that soil nitrogen amendments will improve the therapeutic qualities of lemongrass, along with the strengthening of its antioxidant machinery, upon exposure to O3 stress.

Preserving plum perfection: Buckwheat starch edible coating with xanthan gum and lemongrass essential oil.

The research focused on the fabrication of composite coatings using buckwheat starch (BS) and xanthan gum (XG) with incorporation of lemongrass (Cymbopogon citratus) essential oil (LEO) with varying concentration (0.75 %, 1.0 % and 1.25 % (w/v). BS was extracted from buckwheat groats (Fagopyrum esculentum) and its physico-chemical characteristics were determined. BS showed spherical and polygonal morphology and its XRD pattern was similar to starch extracted from other cereal sources. The amount of reducing sugar, starch and amylose content in extracted BS were 0.99 ± 0.33 %, 86.32 ± 0.22 % and 21.02 ± 1.89 % respectively, which indicates that BS is a suitable base material for the formation of edible coatings. XG was mixed with BS in different ratios (1:1, 2:1, 3:1 and 4:1) to optimize the best ratio of combination for composite coatings. The coating with a ratio of 2:1 was very smooth and was chosen for incorporation of LEO and the coatings physical, functional, mechanical, thermal and micro-structural characteristics were examined. The coating S5 with 1.25 % (w/v) concentration of LEO showed the best results with least moisture content (MC), minimum water vapor permeability (WVP) and maximum contact angle value. Moreover, the S5 formulation had the highest antioxidant (73.3 %) ability and maximum antimicrobial efficiency with inhibition zones of 22.09 ± 0.06 mm and 28.65 ± 0.14 mm against S. aureus and E. coli respectively. The coatings were then coated on plum fruit, and various parameters like weight loss, pH, shrinkage and TSS were calculated every 4th day during the 20 days of refrigeration period. The coated plums' ripening pace was delayed by the S5 formulation which improved moisture retention, maintained the plums' TSS value and overall pH. Therefore, composite coatings made up of BS, XG and 1.25 % (w/v) can be used as a cost-effective bio-active coating material for plum preservation under refrigeration conditions.

Speciation, phytoavailability, and accumulation of toxic elements and sulfur by humic acid-fertilized lemongrass and common sage in a sandy soil treated with heavy oil fly ash: A trial for management of power stations wastes.

Globally, power stations generate huge amounts of the hazardous waste heavy oil fly ash (HOFA), which is rich in Ni, V, Fe, S, and dumped into landfills. Thus, exploring new approaches for a safe recycling and sustainable management of HOFA is needed and of great environmental interest. The potential application of HOFA as an amendment to sandy soils has not been studied yet. This is the first research investigating the potentiality of using HOFA as a soil conditioner. To this end, we conducted a greenhouse experiment in order to investigate the impacts of HOFA addition (1.2, 2.4, 3.6 t ha-1) to sandy soil on the total and available content of nutrients (e.g., S, Fe, Mn, Cu, Zn) and toxic elements (TEs; e.g., Cd, Co, Cr, Ni, Pb, V) in the soil and their phytoextraction and translocation by lemongrass (Cymbopogon citratus) and common sage (Salvia officinalis). We also assessed the impact of humic acid (HA) foliar application (50 and 100 l ha-1) on the growth and elements accumulation by the two plants. The studied HOFA was acidic and highly enriched in S (43,268.0), V (3,527.0), Ni (1774.0), and Fe (15,159.0) (units in mg kg-1). The X-ray absorption near edge structure (XANES) data showed that V in HOFA was composed primarily of V(IV) sorbed onto goethite, V(V) sorbed onto humic substances, in the forms of V2O3, and VCl4. Addition of the lower doses of HOFA (1.2 and 2.4 t ha-1) did not change significantly soil pH, salinity, and the total and available elements content compared to the unamended soil. Although the elements content in the 3.6 t ha-1 HOFA-treated soil was significantly higher than the untreated, the total content of all elements (except for Ni) was lower than the maximum allowable concentrations in soils. HOFA addition, particularly in the highest dose (3.6 t ha-1), decreased significantly the growth and biomass of both plants. Common sage accumulated more elements than lemongrass; however, the elements content in the plants was lower than the critical concentrations for sensitive plants. The foliar application of humic acid enhanced significantly the plant growth and increased their tolerance to the HOFA-induced stress. We conclude that the addition of HOFA up to 2.4 t ha-1 in a single application as amendment to sandy soils is not likely to create any TE toxicity problems to plants, particularly if combined with a foliar application of humic acid; however, repeated additions of HOFA may induce toxicity. These findings should be verified under field conditions.

Extraction of geraniol from palmarosa oil using hydrotropic solvents / Extracción de geraniol del aceite de palmarosa utilizando solventes hidrotrópicos

The extraction of geraniol from palmarosa oil using hydrotropic solvents was investigated. Palmarosa oil possesses an appealing rose aroma and properties like anti - inflammatory, antifungal, and antioxidant due to the presence of geraniol. The extraction of geraniol from palmarosa oil by using distillation methods like steam dis tillation and fractional distillation was a laborious process. So hydrotropes were tried for extraction. The geraniol yield and purity depend on parameters like concentration of hydrotrope, solvent volume ratio, and time period. Using the Box Benkhem Desig n (BBD), the extraction process was optimized. One of the major advantages of using hydrotropic solvents is that they were classified as green solvents, and recovery of solvents is also possible. To reduce the extraction time probe sonication is carried ou t. Different hydrotropic solvents with probe sonication are done on palmarosa oil by altering various process parameters to study the separation, yield, and purity.

Se investigó la extracción de geraniol del aceite de palmarosa utilizando solventes hidrotrópicos. El aceite de palmarosa posee un atractivo aroma a rosa y propiedades antiinflamatorias, antifúngicas y antioxidantes debido a la pr esencia de geraniol. La extracción de geraniol del aceite de palmarosa mediante métodos de destilación como la destilación por vapor y la destilación fraccionada ha sido un proceso laborioso. Por lo tanto, se probaron los hidrotropos para la extracción. El rendimiento y la pureza del geraniol dependen de parámetros como la concentración del hidrotropo, la relación de volumen del solvente y el período de tiempo. Se optimizó el proceso de extracción usando el diseño Box Benkhem (BBD). Una de las principales v entajas de usar solventes hidrotrópicos es que se clasifican como solventes verdes y también es posible recuperar los solventes. Para reducir el tiempo de extracción, se lleva a cabo una sonda de ultrasonido. Se realizan diferentes solventes hidrotropos co n sonda de ultrasonido en el aceite de palmarosa alterando varios parámetros del proceso para estudiar la separación, el rendimiento y la pureza.

Preparation and application of hydroxypropyl methylcellulose blended with beeswax and essential oil edible coating to enhance the shelf life of sweet cherries.

The study involved preparing and applying edible nano-emulsion coatings containing hydroxypropyl methylcellulose (HPMC), beeswax (BW), and essential oils (thyme, cinnamon, clove, and peppermint) onto sweet cherries. The application was conducted at 4 °C, and the coated cherries were stored for 36 days. This research examines synthesized nano-emulsions physicochemical properties and antibacterial and antifungal activities (C1, C2, and C3). Additionally, it evaluates the quality parameters of control and coated sweet cherry samples. The features of the three edible coatings were assessed, and the findings from the zeta sizer, zeta potential, FTIR, and SEM analyses were deemed satisfactory. It was observed that the application of nano-emulsion coating C1 yielded positive results in maintaining quality attributes such as total suspended solids (TSS), total solids (TS), color, weight loss, respiration rate, firmness, total phenolic contents, and sensory evaluations. Nano-emulsion coating C1 demonstrated efficacy as an antibacterial and antifungal agent against foodborne pathogens E. coli and A. niger, respectively. The current research results are promising and applicable in food industries. The implications suggest that composite nano-emulsion, specifically nano-emulsion edible coatings, can be extensively and effectively used to preserve the quality and shelf life of fruits and vegetables. Furthermore, the environmental waste from conventional food packaging will be minimized using edible packaging applications.

Comprehensive characterization of microcrystalline cellulose from lemon grass (Cymbopogan citratus) oil extraction agro-industrial waste for cementitious composites applications.

Presently, the construction industry demands components that are exceptionally strong and long-lasting. The initial important construction material is concrete, which contains between 1 % and 2 % of air voids. The structural damage caused by water that enters through the air spaces are improved with filler material. Chemical filler materials are environmentally harmful; therefore, eco-friendly materials are selected for this study. The environmentally benign character of agro-waste byproduct usage is a driving factor in the field of research. Numerous uses can be found for waste materials, especially after they have been repurposed. We used a byproduct of an essential oil extraction company, an extract made from the leaves of lemon grass (Cymbopogan citrus), in our research. Alkalization, slow pyrolysis, acid hydrolysis, and bleaching are only some of the chemical treatments that could be used to easily extract microcrystalline cellulose from the discarded waste material. In our study the chemicals used are mild harmful to the environment and a surface reactant (linear alkyl benzene sulfonic acid) is utilised to bleach and purify the microcrystalline cellulose. Thermal analysis, scanning electron microscopy, transmission electron microscopy and Fourier transform spectroscopy were all used to learn more about the cellulose that had been extracted. The extracted cellulose powder comprises a high crystallinity index (68.14 %) and low crystallite size (5.13 nm) found using X-ray diffraction analysis. The smooth and porous surface is observable in scanning electron microscope analysis. The Differential scanning calorimeter curve shows the highest degradation temperature at 218.16 °C. The micro sized particles mostly range between 100 and 120 µm and are found using ImageJ. The surface roughness and permissible skewness of cellulose particles were examined using atomic force microscopy. The density of extracted cellulose is 1.092 g/cm3. The microcrystalline cellulose yield % was notably maximum (40.45 %). This cellulose was introduced in a M30 grade cement concrete as fillers up to 5 % by the weight of cement. The fresh and mechanical properties of the concrete was found to get improved with the addition of cellulose up to 3 %. As a result, the characteristics of cellulose boost its utility within the construction sector.

Antibacterial activity of Cymbopogon species essential oils against Xanthomonas citri and their use in post-harvest treatment for citrus canker management.

Citrus canker is a disease caused by the gram-negative bacterium Xanthomonas citri subp. citri (X. citri), which affects all commercially important varieties of citrus and can lead to significant losses. Fruit sanitization with products such as chlorine-based ones can reduce the spread of the disease. While effective, their use raises concerns about safety of the workers. This work proposes essential oils (EOs) as viable alternatives for fruit sanitization. EOs from Cymbopogon species were evaluated as to their antibacterial activity, their effect on the bacterial membrane, and their ability to sanitize citrus fruit. The in vitro assays revealed that the EOs from C. schoenanthus and C. citratus had a lower bactericidal concentration at 312 mg L-1, followed by 625 mg L-1 for C. martini and C. winterianus. Microscopy assay revealed that the bacterial cell membranes were disrupted after 15 min of contact with all EOs tested. Regarding the sanitizing potential, the EOs with higher proportions of geraniol were more effective in sanitizing acid limes. Fruit treated with C. shoenanthus and C. martini showed a reduction of ∼68% in the recovery of viable bacterial cells. Therefore, these EOs can be used as viable natural alternatives in citrus fruit disinfection.