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The global population is rising at an alarming rate, which is threatening food and nutritional security. Although chemical fertilizers and pesticides are important for achieving food security, their excessive usage critically affects soil health and adds up residues in the food chain. There is an increasing interest in identifying eco-friendly farm inputs that can improve crop productivity through sustainable agricultural practices. One of the most common approaches to reducing chemical inputs in agriculture is the use of plant growth regulators (PGRs). Here, we demonstrate the benefits of a natural and novel plant growth enhancer "calliterpenone," isolated from Callicarpa macrophylla, a medicinal plant, for increasing crop productivity in six crops, viz., rice, wheat, potato, tomato, chickpea, and onion. Results revealed that the application of calliterpenone (foliar spraying or seed soaking) enhanced the yield of rice (28.89%), onion (20.63%), potato (37.17%), tomato (28.36%), and chickpea (26.08%) at 0.001 mM and of wheat (27.23%) at 0.01 mM concentrations in comparison to control. This enhancement in yield was reflected through improvements in its growth attributes, viz., spike length, tillers plant-1, seeds spike-1, plant height, and biomass. Furthermore, the exogenous application of calliterpenone could increase the endogenous level of indole-3-acetic acid (IAA) in all tested crops and decrease the content of abscisic acid (ABA) in a few. Trials conducted at farmers' fields showed an overall ~12% increase in rice yield (mean of 11 farmers' fields ranging from 3.48 to 19.63%) and ~10% increase in wheat yield (ranging from 3.91 to 17.51%). The 0.001 mM of calliterpenone was the best effective dose for most crops except wheat, where a concentration of 0.01 mM was found to be the most optimal. This study indicates that calliterpenone is a natural plant growth promoter that can be used in boosting the yields of multiple crops and would be an important input component of organic farming. [ABSTRACT FROM AUTHOR]

Ravenia spectabilis Engl. belongs to the family Rutaceae is known to possess several biologically active phytomolecules. This study was planned to investigate the chemical composition and antimicrobial activity of the leaf essential oil of R. spectabilis. The hydrodistillation of fresh leaves of R. spectabilis gave 0.19 ± 0.02% essential oil. The resulting essential oil was analysed by gas chromatography-flame ionization detector (GC-FID) and gas chromatography-mass spectrometry (GC-MS). Altogether, thirty-one constituents forming 97.6 ± 1.72% of the total oil composition were identified. Major components of the oil were sabinene (60.8 ± 0.36%), α-pinene (5.4 ± 0.30%), myrcene (4.8 ± 0.25%), δ-3-carene (4.7 ± 0.62%) and β-pinene (4.3 ± 0.17%). The in-vitro antimicrobial potential of the oil was examined against eight human pathogenic bacterial and fungal strains. The essential oil showed significant activity against Staphylococcus aureus, Staphylococcus epidermidis, methicillin-resistant Staphylococcus aureus, methicillin-resistant Staphylococcus epidermidis, Candida albicans, and Candida kefyr. This is the first report on R. spectabilis leaf essential oil composition and its antimicrobial activity. The essential oil could be a promising natural source of sabinene and antimicrobial for developing new phytotherapeutics. [ABSTRACT FROM AUTHOR]

Artemisia pallens Wall. ex DC, commonly known as davana, is cultivated in India for extraction of its essential oil (DO). In this study, DO collected from thirteen locations (DO1-DO13) and those extracted from six different phenophases and different plant parts were investigated using GC-FID and GC-MS. Altogether, 84 constituents were identified, forming 81.0–96.2% of the total oil composition. Major components of the oils were cis-davanone (17.4–65.1%), bicyclogermacrene (4.0–22.0%), cis-methyl jasmonate (0.4–8.5%), β-eudesmol (0.3–6.6%), davana ether isomer (0.5–6.1%), trans-ethyl cinnamate (1.4–6.1%), and germacrene D (0.1–4.7%). Among all tested oils, the DO10, having low cis-davanone content (27.5%), was found more potent against test microorganisms. The oils collected from different locations showed variations in their physical properties, chemical composition, and antimicrobial activity. Based on the yield and cis-davanone content, the flower bud and full-flowering stages could be suitable for harvesting good quality oil in north Indian plains. [ABSTRACT FROM AUTHOR]

Chemical investigations on the stem of Cuscuta reflexa Roxb. (Convolvulaceae) led to the isolation of one new compound characterised as 3′,4′-dimethoxy-1-phenyl-1α, 2-ethanediol (1), along with eight known compounds as tridecanyl palmitate, palmitic acid, n-pentatriacontane, n-triacont-21, 27-dien-1-ol, kaempherol, chlorogenic acid, 5,7-dimethoxyapigenin and quercitin. The chemical structures were established with the help of physical, chemical and spectroscopic methods. The antimicrobial potential of the new compound (1) was evaluated against three bacterial and three fungal pathogenic strain and showed significant activities. [ABSTRACT FROM AUTHOR]

The aim of the study was to investigate the chemical composition and antimicrobial activity of the essential oil of the senescent leaves of Psidium guajava L. (Myrtaceae). The hydrodistilled essential oil of the leaves was analysed by GC-FID and GC-MS. The antimicrobial activity of the oil was assessed against human and plant pathogenic microorganisms by disc diffusion, microdilution broth and poison food techniques. A total of forty-six constituents, representing 90.9% of the total oil composition were identified. Major constituents of the oil were limonene (29.1%), (E)-caryophyllene (15.7%), caryophyllene oxide (8.8%), caryophylla-4(12),8(13)-dien-5-ol (6.5%), (E)-nerolidol (4.0%), α-cadinol (3.4%), and muurola-4,10(14)-dien-1-β-ol (2.5%). The chemical composition of the examined essential oil was quite different from those reported earlier. The essential oil showed significant inhibition of human pathogenic bacteria (MIC: 0.065–0.261 mg/mL) and plant pathogenic fungi, namely Curvularia lunata (86.02%) and Fusarium chlamydosporum (82.80%). [ABSTRACT FROM AUTHOR]

Present study was aimed to investigate the antibacterial activity, bactericidal mechanism of action, killing kinetics and anti-inflammatory activity of Isodon melissoides (Benth.) H. Hara essential oil. The gas chromatography-flame ionization detector (GC-FID) and gas chromatography-mass spectrometry (GC-MS) analysis revealed the presence of carvacrol (45.4%), p-cymene (11.6%) and thymol (11.3%) as major constituents of the oil. The oil displayed broad spectrum significant antibacterial activity (MIC: 0.13–8.33 ppm; MBC: 0.13–>33.34 ppm) against test strains. The oil exhibited a time and dose-dependent bactericidal effect. The oil disrupted the cell membrane by changing the cell membrane permeability. The essential oil significantly decreased the overproduction of proinflammatory cytokines in LPS-induced inflammation in HaCaT cells without any cytotoxic effect. I. melissoides essential oil can be a promising alternative antimicrobial agent for the control of methicillin resistant staphylococci and other pathogenic bacteria tested, and also useful for the topical anti-inflammatory properties. [ABSTRACT FROM AUTHOR]

Citronella (Cymbopogon spp.) essential oil is an important component of various fragrances, cosmetics, and household products. In this study, comparative chemical composition and antimicrobial activity of Java citronella (Cymbopogon winterianus Jowitt ex Bor) essential oil, extracted by different methods, namely hydro-distillation and steam-distillation were determined by GC, GC-MS, and disc diffusion assay and microdilution broth assay. Major constituents of the essential oil were citronellal (2.2–55.4%), geraniol (14.2–53.0%), citronellol (8.2–16.4%), isopulegol (0.3–12.6%), elemol (0.8–8.2%), and limonene (0.2–5.0%). The essential oils showed inhibition of test bacteria with minimum inhibition concentration (MIC) in the range of 250–1000 µg/mL and showed anticandidal activity with MIC in the range of 125–500 µg/mL. In general, the oils were moderately active against Gram-positive and Gram-negative bacterial strains and also showed good activity against Candidal strains. The essential oils extracted from the herbage by different techniques exhibited variations in their yield, chemical composition, and antimicrobial activities. [ABSTRACT FROM AUTHOR]

A polyphenolic flavonoid, Silymarin isolated from Silybum marianum is widely known for its hepatoprotective action. In the present study anti-plasmodial activity of Silymarin has been demonstrated for the first time having IC50 of 14 ± 0.33 μM against the NF-54 strain of P. falciparum with high selectivity index (>100). The parasitostatic action is exerted through inhibition of β-hematin/hemozoin formation which is due to the interaction (Kd = 3.63 ± 0.9µM) of silymarin with free heme in a Stoichiometry of 1:1 Silymarin: heme complex resulting into heme-induced membrane damage in the parasite. Silymarin could hinder the glutathione and hydrogen peroxide-induced heme detoxification. Silymarin also induces apoptosis in the parasite through the elevation of caspase-3 level in a dose-dependent manner. Results from the docking studies suggest that Silymarin interacts with heme. [ABSTRACT FROM AUTHOR]

In this study, antimicrobial activity of the essential oil (EO) and extracts of Himalayan-thyme (Thymus linearis Benth.) was evaluated against nine pathogenic microbial strains using disc diffusion and microdilution broth assays. The chemical composition of the EO was determined by gas chromatography-flame ionisation detector (GC-FID) and gas chromatography-mass spectrometry (GC-MS). The molecular mechanism of action of the EO was investigated against three pathogenic bacteria (Staphylococcus aureus, Staphylococcus epidermidis and Enterococcus faecalis) and three fungal strains (Candida albicans, Candida glabrata, and Candida tropicalis) using the assays of protein leakage, and DNA and RNA leakage through the membrane. Major components of the EO were thymol (54.9%), γ-terpinene (16.6%) and p- cymene (5.2%). The EO showed broad-spectrum potent antibacterial and antifungal activity (MIC 240–990 µg/mL) against test strains. The EO damaged cell membranes and altered cell membrane permeability of test microorganisms. The EO showed a time- and dose-dependent bactericidal and fungicidal effect. It could act as a promising antimicrobial agent due to its short killing time. [ABSTRACT FROM AUTHOR]

Eugenol is a phytochemical present in aromatic plants has generated considerable interest in the pharmaceutical industries mainly in cosmetics. A series of eugenol esters (ST1-ST7) and chloro eugenol (ST8) have been synthesized. The structures of newly synthesized compounds were confirmed by ¹H and 13C NMR and mass spectrometry. In an effort to evaluate the pharmacological activity of eugenol derivatives, we explored its anti-inflammatory potential against skin inflammation using in-vitro and in-vivo bioassay. Synthesized derivatives significantly inhibited the production of pro-inflammatory cytokines against LPS-induced inflammation in macrophages. Among all derivatives, ST8 [Chloroeugenol (6-chloro, 2-methoxy-4-(prop-2-en-1-yl)-phenol)] exhibited most potent anti-inflammatory activity without any cytotoxic effect. We have further evaluated the efficacy and safety in in-vivo condition. ST8 exhibited significant anti-inflammatory activity against TPA-induced skin inflammation without any skin irritation effect on experimental animals. These findings suggested that ST8 may be a useful therapeutic candidate for the treatment of skin inflammation. [ABSTRACT FROM AUTHOR]

Prostate cancer is fourth most abundant cancer type around the globe. Brevifoliol, a rearranged taxoid from Taxus walllichiana needles has been derivatized as C5 esters using Steglich esterification reaction. Seventeen diverse analogues were evaluated against a panel of human cancer cell lines by MTT assay. Among these, two of the semi‐synthetic analogues, that is, 13 and 16 exhibited potent cytotoxicity, selectively against PC‐3, prostate cancer cell lines. In cell cycle analysis, analogue 13 induced S and G2/M phase arrest and induced apoptosis by activating caspase‐3. Compound 13 showed moderate efficacy in in‐vivo Ehrlich ascites carcinoma in Swiss albino mice. Further, compound 13 was found to be safe in Swiss albino mice up to 1,000 mg/kg dose in acute oral toxicity. Brevifoliol ester 13 may further be optimized for better efficacy. [ABSTRACT FROM AUTHOR]

Background: Three key coumarinolignoids, cleomiscosins A, B, and C of Cleome viscosa seed origin in particular ratio, are a proven hepatoprotective agent known as Cliv-92. Objectives: However, the bioavailability and pharmacokinetics of Cliv-92 are still not clear. The present study is the first validated method which deals with the assay of Cliv-92 in mouse plasma. Methods: Single-step sample preparation meets the criteria of recovery (80%-93% with relative standard deviation [RSD] 2.14%-4.80%). Reverse-phase high-performance liquid chromatography with photodiode array detection has resulted into acceptable separation and sensitivity of three structurally similar cleomiscosins - A, B, and C of Cliv-92. The analysis involved a binary gradient of mobile phase and flow rate. Quantification was done at peak area at 326 nm using linear regression curve (r² > 0.999). The precision (0.46%-2.68% RSD) and accuracy (±2.09% bias) of Cliv-92 determination in plasma complied the criteria of the current international guidelines. We have also evaluated the matrix effect on sensitivities by spiking method. Limit of detection and limit of quantification in mouse plasma ranged between 0.13-0.24 µg/ml and 0.41-0.74 µg/ml. Results: Pharmacokinetic parameters were studied after intravenous bolus administration of Cliv-92 at 10 mg/kg dose in mice. Blood samples were collected at a predefined time up to 24 h post-injection. The Cliv-92 plasma half-life (t1/2) was 2.77 h, and the clearance was estimated as 2.38 L/h/kg. Conclusion: The method is simple, sensitive, and accurate for the determination of plasma concentration of coumarinolignoids. The present preclinical pharmacokinetic study of coumarinolignoids has been anticipated in clinical studies with scaling techniques. [ABSTRACT FROM AUTHOR]

Chemical investigations on the fruits of Zanthoxylum armatum Roxb. (Rutaceae) led to the isolation of two new constituents characterised as 2α-methyl-2β-ethylene-3β-isopropyl-cyclohexan-1β, 3α-diol (1) and phenol-O-β-D-arabinopyranosyl-4′-(3″, 7″, 11″, 15″-tetramethyl)-hexadecan-1″-oate (2) along with known compounds m-methoxy palmityloxy benzene (3), acetyl phenyl acetate (4), linoleiyl-O-α-D-xylopyranoside (5), m-hydroxyphenoxy benzene (6) and palmitic acid (7). The chemical structures were established with the help of physical, chemical and spectroscopic methods. The anti-inflammatory potential of isolated compounds 1 and 2 was evaluated using in vitro target-based anti-inflammatory activity in LPS-stimulated primary peritoneal macrophages isolated from mice. Production of pro-inflammatory cytokines (TNF-α and IL-6) was significantly inhibited by the treatment of isolated compounds 1 and 2 in a dose-dependent manner. [ABSTRACT FROM AUTHOR]

A practical and novel approach has been developed for the synthesis of oleanolic acid based chromene analogues. Different α,β-unsaturated carbonyl and chromene derivatives of oleanolic acid were synthesized and evaluated for their anticancer activity. Compounds 6e, 6k, 7e and 7g showed significant anticancer activity within the IC50 range of 12.23–39.04 μg mL−1. The promising derivatives 7e and 7g were further analyzed for their effects on the cell cycle and apoptosis in A-549 and MDA-MB-231 cells, and it was depicted that 7e and 7g triggered apoptosis in A-549 and MDA-MB-231 cells and arrested the cell population in the G2/M phase. The anticancer activity of the most active analogue 7g occurred through microtubule destabilization (IC50: ∼3.6 μg mL−1), and it was found to be non-toxic against human erythrocytes. The compounds 7e and 7g significantly inhibited the proinflammatory cytokines TNF-α and IL-6. [ABSTRACT FROM AUTHOR]

In traditional, herbal medicine, and aromatherapy, use of essential oils and their aroma compounds have been known since long, for the management of various human diseases. The essential oil is a mixture of highly complex, naturally occurring volatile aroma compounds synthesized by medicinal and aromatic plants as secondary metabolites. Essential oils widely used in pharmaceutical, cosmetic, sanitary, food industry and agriculture for their antibacterial, antiviral, antifungal, antiparasitic, insecticidal, anticancer, neuroprotective, psychophysiological, and anti-aging activities. Moreover, volatile aroma compounds comprise a chemically diverse class of low molecular weight organic compounds with significant vapor pressure. However, aroma compounds produced by plants, mainly attract pollinators, seed dispersers and provide defense against pests or pathogens. However, in humans, about 300 active olfactory receptor genes are involved to detect thousands of different aroma compounds and modulates expression of different metabolic genes regulating human psychophysiological activity, brain function, pharmacological signaling, and therapeutic potential. Keeping in mind this importance, present database, namely, AromaDb (http://bioinfo.cimap.res.in/aromadb/) covers information of plant varieties/chemotypes, essential oils, chemical constituents, GC-MS profile, yield variations due to agromorphological parameters, trade data, aroma compounds, fragrance type, and bioactivity details. The database includes 1,321 aroma chemical structures, bioactivities of essential oil/aroma compounds, 357 fragrance type, 166 commercially used plants, and their high yielding 148 varieties/chemotypes. Also includes calculated cheminformatics properties related to identification, physico-chemical properties, pharmacokinetics, toxicological, and ecological information. Also comprises interacted human genes affecting various diseases related cell signaling pathways correlating the use of aromatherapy. This database could be a useful resource to the plant's growers/producers, an aroma/fragrance industrialist, health professionals, and researchers exploring the potential of essential oils and aroma compounds in the development of novel formulations against human diseases. [ABSTRACT FROM AUTHOR]

Background: Staphylococcus aureus (SA), is a major human pathogen causing wide range of clinical infections, which has been further complicated by drug resistance like methicillin resistant S. aureus (MRSA), vancomycin intermediate S. aureus (VISA)/vancomycin resistant S. aureus (VRSA), etc. The present study was aimed at determining anti-staphylococcal potential of citral against drug resistant clinical isolates alone and in combination with antibiotics.Purpose: To assess the potential of citral in combination with norfloxacin in treating drug resistant infections of SA.Study Design: In the present study, synergistic interaction of citral and norfloxacin against drug resistant SA strains was evaluated. Further the efficacy and possible mechanism of action of the combination was also evaluated using in vitro and in vivo assays.Method: The anti-staphylococcal activity of each of the monoterpene and the antibiotic was determined in terms of MIC and the effective concentration of both compounds in combination was obtained by checkerboard assay. In vivo efficacy and oral acute toxicity was evaluated in Swiss albino mice model. To understand the mechanism of action, time-kill curve, bacteriolysis, leakage, membrane depolarization, salt tolerance and ethidium bromide efflux assays were performed.Results: Citral was found effective against clinical isolates of SA with MIC values ranging from 75 to 150 µg ml-1 exhibiting bacteriostatic activity. Citral interacted synergistically, reducing MIC of norfloxacin up to 32-folds with FICI ≤ 0.50. Citral did not affect cell wall, but could damage cell membrane, inhibit efflux pump and affect the membrane potential. Citral could reduce the staphylococcal load of spleen and liver tissues in a dose-dependent manner which was further reduced when used in combination with norfloxacin. Citral did not exhibit any mortality or morbidity up to 500 mg kg-1 body weight and found to prolong the post-antibiotic effect of norfloxacin.Conclusion: Based on these observations, citral could be a lead candidate phytomolecule for further developing it into an anti-staphylococcal agent. The observations of combination study will help in reducing the burden of antibiotics leading to delayed resistance development. [ABSTRACT FROM AUTHOR]

Xanthomonas oryzae pv. oryzae (Xoo), a common bacterial plant pathogen regulates its virulence and biofilm formation attribute via a chemical method of communication. Disabling this mechanism offers a promising alternative to reduce the virulence and pathogencity of the microorganism. In this study, the effect of thyme (THY) oil on Quorum Sensing mediated synthesis of various virulence factors and biofilm formation was analyzed. Treatment of Xoo with 500 ppm THY oil displayed a significant diminution in swimming, swarming, exopolysaccharide and xanthomonadin secretion. However, no effect was observed on bacterial growth kinetics and metabolic activity of the cells. Results were further authenticated by RT-qPCR as significant reduction in motA, motB, and flgE genes was observed upon THY oil treatment. Similarly, the expression of some extracellular enzyme genes such as endoglucanase, xylanase, cellobiosidase, and polygalacturonase was also found to be significantly reduced. However, biochemical plate assays revealed insignificant effect of 500 ppm THY oil on secretion of protease, cellulase, and lipase enzymes. The rpfF gene known to play a crucial role in the virulence of the phytopathogenic bacteria was also significantly reduced in the THY oil treated Xoo cells. HPTLC analysis further revealed significant reduction in DSF and BDSF signaling molecules when Xoo cells were treated with 500 ppm THY oil. Disease reduction was observed in in vitro agar plate assay as lesion length was reduced in THY oil treated Xoo cells when compared with the alone treatment. GC-MS result revealed thymol as the active and major component of THY oil which showed potential binding with rpfF gene. Application of 75 μM thymol resulted in downregulation of gumC, motA, estA, virulence acvB and pglA along with rpfF. The other genes such as cheD, flgA, cheY, and pilA, were not found to be significantly affected. Overall, the results clearly indicated THY oil and its active component Thymol to be a potential candidate for the development of anti-virulence agent which in future when applied in combination with conventional bactericides might not only help in lowering the dose of bactericides but also be successful in curbing the disease progression in rice. [ABSTRACT FROM AUTHOR]

Background: Pyrethrins are monoterpenoids and consist of either a chrysanthemic acid or pyrethric acid with a rethrolone moiety. Natural pyrethrins are safe and eco-friendly while possessing strong insecticidal properties. Despite such advantages of commercial value coming with the eco-friendly tag, most enzymes/genes involved in the pyrethrin biosynthesis pathway remain unidentified and uncharacterized. Since the flowers of Tanacetum cinerariifolium are rich in major pyrethrins, next generation transcriptome sequencing was undertaken to compare the flowers and the leaves of the plant de novo to identify differentially expressed transcripts and ascertain which among them might be involved in and responsible for the differential accumulation of pyrethrins in T. cinerariifolium flowers. Results: In this first tissue specific transcriptome analysis of the non-model plant T. cinerariifolium, a total of 23,200,000 and 28,500,110 high quality Illumina next generation sequence reads, with a length of 101 bp, were generated for the flower and leaf tissue respectively. After functional enrichment analysis and GO based annotation using public protein databases such as UniRef, PFAM, SMART, KEGG and NR, 4443 and 8901 unigenes were identified in the flower and leaf tissue respectively. These could be assigned to 13344 KEGG pathways and the pyrethrin biosynthesis contextualized. The 2-C-methyl-D-erythritol 4-phosphate (MEP) pathway was involved in the biosynthesis of acid moiety of pyrethrin and this pathway predominated in the flowers as compared to the leaves. However, enzymes related to oxylipin biosynthesis were found predominantly in the leaf tissue, which suggested that major steps of pyrethrin biosynthesis occurred in the flowers. Conclusions: Transcriptome comparison between the flower and leaf tissue of T. cinerariifolium provided an elaborate list of tissue specific transcripts that was useful in elucidating the differences in the expression of the biosynthetic pathways leading to differential presence of pyrethrin in the flowers. The information generated on genes, pathways and markers related to pyrethrin biosynthesis in this study will be helpful in enhancing the production of these useful compounds for value added breeding programs. Related proteome comparison to overlay our transcriptome comparison can generate more relevant information to better understand flower specific accumulation of secondary metabolites in general and pyrethrin accumulation in particular. [ABSTRACT FROM AUTHOR]