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The pandemic of viral diseases like novel coronavirus (2019-nCoV) prompted the scientific world to examine antiviral bioactive compounds rather than nucleic acid analogous, protease inhibitors, or other toxic synthetic molecules. The emerging viral infections significantly associated with 2019-nCoV have challenged humanity's survival. Further, there is a constant emergence of new resistant viral strains that demand novel antiviral agents with fewer side effects and cell toxicity. Despite significant progress made in immunization and regenerative medicine, numerous viruses still lack prophylactic vaccines and specific antiviral treatments that are so often influenced by the generation of viral escape mutants. Of importance, medicinal herbs offer a wide variety of therapeutic antiviral chemotypes that can inhibit viral replication by preventing viral adsorption, adhering to cell receptors, inhibiting virus penetration in the host cell, and competing for pathways of activation of intracellular signals. The present review will comprehensively summarize the promising antiviral activities of medicinal plants and their bioactive molecules. Furthermore, it will elucidate their mechanism of action and possible implications in the treatment/prevention of viral diseases even when their mechanism of action is not fully understood, which could serve as the base for the future development of novel or complementary antiviral treatments.

The excessive use of conventional insecticides to Culicidae leads to the emergence of mosquitoe resistant, adverse environmental and human effects. Therefore, the present study was carried out to explore the larvicidal efficacy of petroleum ether, chloroform, ethyl acetate and methanol extracts of roots, leaves, and bark of Neolamarckia cadamba against the early 4th instar larvae of Anopheles stephensi, Aedes aegypti and Culex quinquefasciatus at concentrations ranging from 12.5 to 200 ppm under laboratory conditions. The root extracts showed the highest larvicidal potential than the leaf and bark extracts. After 24 h of exposure period, the highest larvicidal activities were observed in the methanol extract of roots with LC50 value of 43.29 and LC90 value of 202.85 ppm against An. stephensi; LC50 value of 70.82 and LC90 value of 253.73 ppm against Ae. Aegypti and LC50 value of 99.51 and LC90 value of 311.02 ppm against the Cx. Quinquefasciatus, respectively. Thus, the plant extracts of N. cadamba showed considerable mosquito larvicidal activities and can be considered for further investigation.

The vector-borne diseases caused by mosquitoes are one of the major health problems around the world especially in tropical and sub-tropical countries. The present study was carried out to evaluate the larvicidal potential of petroleum ether, chloroform, ethyl acetate and methanol extracts of root and leaves of Senecio laetus Edgew. against the early fourth-instar larvae of the malarial vector, Anopheles stephensi; dengue vector, Aedes aegypti and the filarial vector, Culex quinquefasciatus. The root and leaf extracts of S. laetus at 200, 100, 50, 25 and 12.5 ppm caused a significant mortality of the tested mosquito species and root extracts showed the highest larvicidal potential than the leaf extracts. After 12 and 24 h of exposure period, the highest larvicidal activities were observed in the methanol extract of root with LC50 = 24.68 and 16.70 ppm and LC90 = 200.42 and 109.19 ppm for An. stephensi; LC50 = 44.25 and 22.30 ppm and LC90 = 266.19 and 144.67 ppm for Ae. aegypti and LC50 = 84.14 and 30.68 ppm and LC90 = 291.17 and 183.84 ppm for C. quinquefasciatus at 200 to 12.5 ppm respectively. Further, gas chromatography–mass spectroscopy (GC–MS) analysis was carried out to identify the bioactive chemical constituents present in the methanol extract of root of Senecio laetus. GC–MS analysis revealed the presence of 29 compounds. The major chemical constituents identified were D:C-Friedours-7-en-3-ol, (3.beta.), Seneciphylline, β-Sitosterol, 5-Hydroxymethylfurfural, 1H-Pyrrolo [2,3-b]pyridine-1-propionitrile, 2-phenyl- and n-Hexadecanoic acid. Further in-depth study is needed to identify and characterize the active molecule responsible for the larvicidal activities which are underway in our laboratory.

The diseases vectored by mosquitoes continue to be a main cause of illnesses and death throughout the world. The methanol extract of Juglans regia male flower was screened for larvicidal activity against three therapeutically important mosquito vectors viz., malarial vector, Anopheles stephensi; dengue vector, Aedes aegypti and the filarial vector, Culex quinquefasciatus. The larvicidal activity was assayed against the early fourth-instar larvae of tested mosquito species at a concentration ranging from 12.5 to 200 ppm under laboratory conditions. The methanol extract recorded significant mortality against the early fourth-instar larvae of the tested species. After 12 and 24 h of exposure period, the highest effect was recorded in An. stephensi with LC50 values of 139.87 and 59.80 ppm and LC90 values of 288.96 and 166.73 ppm, respectively, followed by Ae. aegypti and Cx. quinquefasciatus. The results could be useful in search for newer, safer and more effective natural larvicidal agents.

Achillea millefoilum L. (Yarrow) is an important species of Asteraceae family with common utilization in traditional medicine of several cultures from Europe to Asia for the treatment of spasmodic gastrointestinal disorders, hepatobiliary, gynecological disorders, against inflammation and for wound healing. An extensive review of literature was made on A. millefoilum L. using ethno botanical text books, published articles in peer-reviewed journals, unpublished materials and scientific databases. The Plant List, International Plant Name Index and Kew Botanical Garden databases were used to authenticate the scientific names. Monoterpenes are the most representative metabolites constituting 90% of the essential oils in relation to the sesquiterpenes, and a wide range of chemical compounds have also been reported. Different pharmacological experiments in many in-vitro and in-vivo models have proved the potential of A. millefoilum with antiinflammatory, antiulcer, anticancer activities etc. lending support to the rationale behind numerous of its traditional uses. Due to the noteworthy pharmacological activities, A. millefoilum will be a better option for new drug discovery. The present review will comprehensively summarize the pharmacognosy, phytochemistry and ethnopharmacology of A. millefoilum reported to date, with emphasis on more in vitro, clinical and pathological studies needed to investigate the unexploited potential of this plant. Copyright © 2017 John Wiley & Sons, Ltd.

The present investigation was carried out to evaluate the antifungal activity of hexane, chloroform, ethyl acetate, acetone and methanol extracts ofCaulerpa chemnitzia, (Epser) J.V. LamououxC. racemosa(Forsk),andC. scalpelliformis(R.Br.) Weber-van-Bosse, (Chlorophyceae) againstCandida albicans,C. krusei,C. guilliermondii,C. parapsilosis,C. tropicalis,C.glabrata, four dermatophytesviz.,Trichophyton rubrum,T. mentagrophytes,Microsporum gypseumandEpidermophyton flocossum. The antifungal activity was evaluated by agar disc diffusion method, determination of MIC and MFC. The mean zones of inhibition produced by the extracts in disc diffusion assay against the tested fungal strains were ranged from 7.1 to 15.1 mm. The lowest MIC (250 µg/ml) and MFC (500 µg/ml) values were observed in the ethyl acetate extract ofC. racemosaagainstC.parapsilosis,C. albicans,C. krusei,C. glabrata,C. guilliermondii, T. rubrum, M. gypseumandT. mentagrophytes.The finding suggests that ethyl acetate extract ofC. racemosashowed the higher antifungal activity againstC.parapsilosisandC. albicans.

The present study larvicidal activities of hexane, chloroform, ethyl acetate, acetone and methanol extracts of Halimeda macroloba, Decsne, Caulerpa racemosa (Frosk) Weber-Van-Bosses and Ulva lactuca Lin, (Chlorophyceae) against Aedes aegypti. The marine macro green algae extracts were tested against early 4th instar larvae of A. aegypti using WHO protocol and concentrations of 200, 400, 600, 800 and 1000 ppm. The observed mortality was made 24 and 48 h after treatment, data was subjected to probit analysis to determine the lethal concentration (LC50 and LC90) of the treated larvae of the tested species.Among the tested extracts the maximum efficicacy was observed in the ethyl acetate extracts. The ethyl acetate extracts of the seaweeds showed the presence of terpenoids, tannins and phenolic compounds stronger than the other extracts. The results revealed that all the extracts showed varied levels of larvicidal activity against A. aegypti tested. However, the ethyl acetate extract of C. racemosa showed remarkable larvicidal activity against A. aegypti (LC50=579.9 and LC90=1255.4 ppm values at 24 h and LC50 =495.4 and LC90 =1073.9 ppm at 48 h) followed by U. lactuca (LC50=588.1 and LC90=1290.7 ppm values at 24 h, and LC50= 530.8 and LC90= 1160.0 ppm at 48 h), respectively. The lowest larval mortality was observed with hexane extract of H. macroloba against A. aegypti with values of LC50=1116.8 and LC90= 1824.5 ppm (after 24 h) and LC50=1059.9 and LC90=1768.3 ppm (after 24 h). The present studies indicate that the larvicidal activity and phytochemicals derived from the ethyl acetate extract of C. racemosa have the potential to be used as an ideal eco-friendly approach and effective mosquito vector control agent.

The present study was aimed to determine the antimicrobial activity of some endemic plant species used in folkloric medicine by the inhabitants of Andaman Islands, India. The ethanol extracts prepared from the leaves of four plants viz; Alstonia kurzii, Tabernaemontana crispa, Mangifera andamanica and Vitex diversifolia were assessed for antibacterial activity against clinically isolated human pathogenic bacteria and antifungal activity against some phytopathogenic fungi. The ethanol extracts showed more inhibition towards Gram positive than Gram negative bacteria and the bacterial strains showed more susceptibility than the fungal strains tested. Among the plants, Vitex diversifolia exhibited the highest antibacterial activity and Mangifera andamanica showed the highest antifungal activity.

Vector-borne diseases transmitted by mosquitoes cause globally important diseases such as malaria, dengue fever, and filariasis. The incidence of these diseases can be reduced through mosquito control programs but these control programs currently rely on synthetic insecticides that can impact the environment, and has selected widespread mosquito resistance. Environment friendly and biodegradable natural insecticides discovered in plants offer an alternative approach to mosquito control. Here, we investigated extracts from root or aerial parts of Chicory (Cichorium intybus) and wormwood (Artemisia absinthium) against the early 4th instar larvae of Anopheles stephensi (malaria vector), Aedes aegypti (dengue fever vector), and Culex quinquefasciatus (filariasis vector). The root and aerial parts extracts of A. absinthium and C. intybus at 200, 100, 50, 25 and 12.5 ppm caused significant mortality of the tested mosquito species. Root extracts exhibited higher larvicidal activity that aerial part extracts. The highest larvicidal activity was recorded in methanol extract of roots of C. intybus with LC50 = 66.16, 18.88 and LC¬90 = 197.56, 107.16 ppm for An. stephensi; LC50 = 78.51, 40.15 and LC90 = 277.31, 231.28 ppm for Ae. aegypti and LC50 = 103.99, 64.56 and LC¬90 = 314.04, 247.54 ppm for Cx. quinquefasciatus. These results reveal potent mosquito larvicidal activity against vectors of malaria, dengue fever, and filariasis is present in extracts of chicory and wormwood.

The Indian Mistletoe Dendrophthoe falcata (L.f) Ettingsh is highly specialized perennial flowering plant adapted to parasitic life on aerial parts of their hosts. Photosynthetic characteristics in leaves of D. falcata growing on a halophilic (Rhizophora mucronata) and a glycophilic (Albizia lebbeck) host trees were determined. The chlorophyll a/b ratio was lower (1.0–1.5) and showed no significant difference between the leaf samples collected from both the host species. The CO2 assimilation rate (PN) was significantly lower (5.2 µmol/(m2 s)) in the parasite growing on R. mucronata, compared to the other host A. lebbeck (6.7 µmol/(m2s)). There was no host-specific variation in the activity of ribulose-1,5-bisphosphate carboxylse (Rubisco) and phosphoenolpyruvate carboxylase (PEPC); however, D. falcata infecting R. mucronata showed significantly higher activity of Rubisco (6.63 mmol CO2/(s kg protein)). The Fourier transform infrared (FTIR) spectral studies revealed the presence of quercitrin in the leaf samples of D. falcata, which is reported as a taxonomic marker of the Loranthaceae family. The non host-specific hemiparasite, D. falcate, exhibited significant variation among the halophilic and glycophilic host trees, particularly in photosynthetic activity and nutrients accumulation.

The present study deals with investigation of larvicidal activity and their chemical constituents of the essential oil from the seeds of Nigella sativa L. (Ranunculaceae). Totally, 18 chemical compounds were identified by GC and GC-MS analysis. Thymol (19.13 %) and α-phellandrene (14.9 %) were identified as major chemical components followed by camphor (12.14 %), borneol (11.31 %), and carvacrol (8.65 %). The larval mortality was observed after 12 and 24 h of exposure period. The results revealed that the essential oil were evaluated against the fourth instar larvae of Aedes aegypti, Anopheles stephensi, and Culex quinquefasciatus. After 12 h of exposure period, the larvicidal activities were LC50 = 196.9 and LC90 = 523.5 ppm (A. aegypti), LC50 = 88.1 and LC90 = 272.4 ppm (A.stephensi), and LC50 = 241.6 and LC90 = 545.4 ppm (C. quinquefasciatus), and the larvicidal activities after 24 h of exposure period were LC50 = 99.9 and LC90 = 300.8 ppm (A. aegypti), LC50 = 53.9 and LC90 = 172.6 ppm (A. stephensi), and LC50 = 141.7 and LC90 = 364.0 ppm (C. quinquefasciatus). The results of the present study showed that the essential oil from seeds of N. sativa is inexpensive food formulation and new source of natural larvicidal agent.

Objective: To evaluate the antibacterial activity of different extracts of Caulerpa chemnitzia (Epser) J.V. Lamououx, Caulerpa racemosa (Frosk.) Weber-van-Bosse (C. racemosa), Caulerpa scalpelliformis (R.Br.) Weber-van-Bosse, Ulva lactuca Lin, Ulva fasciata Dellie, Ulva reticulata Forsk, Stoechospermum marginatum (Ag.) Kutz (S. marginatum), Sargassum wightii Grev, Gracilaria verrucosa (Huds.) Papenfuss and Gracilaria edulis (S.G. Gemelin) P.C. Silva against Enterococcus faecalis (MTCC 439) (E. faecalis) and one clinical isolate of vancomycin resistant E. faecalis. Methods: The selected marine macro algae were extracted with different solvents viz., hexane, chloroform, ethyl acetate, acetone and methanol. Antibacterial assay was carried out by using disc diffusion method, determination of minimum inhibitory concentration and minimum bactericidal concentration. Results: The maximum antibacterial activity was recorded in the ethyl acetate extracts of S. marginatum and C. racemosa than the other extracts. The mean zone of inhibition produced by the extracts in agar diffusion assays against the tested bacterial strains ranged from 7.1 to 14.5 mm. The minimum inhibitory concentration was between 250 and 500 µg/mL, while the minimum bactericidal concentration was from 500 to 1 000 µg/mL. The ethyl acetate extracts of the seaweeds showed the presence of strong terpenoids, tannins and phenolic compounds compared with the other solvent extracts. Conclusions: These findings suggest that ethyl acetate extracts of S. marginatum and C. racemosa can be used as an antibacterial substance for the treatment of infection caused by E. faecalis.

To investigate the antibacterial and antifungal activity of hexane, chloroform, ethyl acetate, acetone and methanol extracts of Gracilaria corticata J. Ag against bacterial and fungal strains viz., Bacillus subtilis, Streptococcus pyogenes, Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, Salmonella typhimurium, Vibrio cholerae, Shigella flexneri, Proteus mirabilis and Proteus vulgaris. Fungal strains Candida albicans, Candida krusei, Candida guilliermondi, Candida parapsilosis, Candida tropicalis, Candida glabrata, four dermatophytes viz., Trichophyton rubrum, Trichophyton mentagrophytes, Microsporum gypseum and Epidermophyton flocossum. The extracts of G. corticata were extracted with different solvents viz., hexane, chloroform, ethyl acetate and methanol against bacterial and fungal strains by using disc diffusion method, MIC, MBC and MFC were determined. The ethyl acetate extract of G. corticata showed the highest antibacterial and antifungal activity against all the bacterial and fungal strains tested than the other extracts. The mean zones of inhibition produced by the extracts in agar disc diffusion assays were from 7.1 to 16.0 mm. The Minimum Inhibitory Concentrations (MIC) was between 125 and 500?g/ml, while the Minimum Bactericidal Concentrations and Minimum Fungicidal Concentrations (MFC) were between 250 and 500?g/ml. The highest mean zone of inhibition (16.0 mm) was observed in ethyl acetate extract of G. corticata against B. subtilis. The lowest MIC (125?g/ml), MBC and MFC (250?g/ml) values was observed in ethyl acetate extract of G. corticata against B. subtilis. The results suggest that the effective ethyl acetate crude extract of G. corticata showed the presence of phytochemical, terpenoids, tannins and phenolic compounds strongly than the other solvent extracts. These finding suggest that ethyl acetate crude extract of G. corticata have potential antimicrobial activity are under going further analysis to identify the active compounds currently progress.

The present study was conducted to evaluate the antibacterial activity of different organic solvent increasing polarity viz., hexane, chloroform, ethyl acetate, acetone and methanol extracts of Ulva fasciata (Chlorophyceae) were collected from Kanniyakummari, Gulf of Mannar biosphere Reserve, Tamilnadu, India. Marine green algae extracts of U. fasciata against multi-drug resistant standard and clinical bacterial strains viz., Bacillus subtilis, Streptococcus pyogenes, Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, Salmonella typhimurium, Vibrio cholerae, Shigella flexneri, Proteus mirabilis and P. vulgaris. The ethyl acetate extracts of U. fasciata showed highest antibacterial activity against all the bacterial strains tested. The mean zone of inhibition produced by the extracts in disc diffusion assays were ranged from 7.1 mm to 15.0 mm. The Minimum Inhibitory Concentrations (MIC) were between 125 μg/ml and 500 μg/ml, while the Minimum Bactericidal Concentrations (MBC) were between 250 μg/ml and 1000 μg/ml. The highest mean of zone inhibition (15.0 mm) and lowest MIC (125 μg/ml) and MBC (250 μg/ml) values were observed in ethyl acetate extract of U. fasciata against B. subtilis. The ethyl acetate extract of the U. fasciata showed the presence of phytochemicals, terpenoids, tannins and phenolic compounds in U. fasciata than the other solvents extracts. The present results of the ethyl acetate extract of U. fasciata can be used as an antibacterial substance for the treatment of multi drug resistant bacterial infections

Essential oil of Chloroxylon swietenia was studied for its antifungal potential against clinically isolated fungal strains as well as the cytotoxic effect on Vero cells. The essential oil was analyzed by gas chromatography (GC) and GC–mass spectrometry (GC–MS). Antifungal activity was studied by disc diffusion method and serial broth dilution method. The toxicity of the essential oil was evaluated in normal Vero cell line by MTT assay. The GC and GC–MS analyses revealed that the essential oil contained 36 compounds and the major chemical compounds were germacrene-D (22.4%) followed by limonene (17.3%) and geijerene (15.4%). The antifungal assay showed that Candida albicans was the most sensitive fungal strain tested, with the strongest mean inhibition zone (22.0±1.32 mm) followed by C. parapsilosis (21.5±1.32 mm). The results of the minimum inhibitory concentration (MIC) indicated that the oil inhibited all the fungal strains tested at the highest concentration of 125 μg/mL. Toxicity on normal Vero cell l...

The fruit pulp essential oil of wood apple (Feronia limonia) was studied for its chemical constituents, in vitro antioxidant and antimicrobial activities. Totally, 50 constituents were identified by GC and GC–MS analyses and thymol (52.22%) was identified as the major chemical compound. The antioxidant activity showed that the essential oil had good scavenging potential viz. DPPH radical (IC50 = 41.35 μg/ml), H2O2 (IC50 = 45.49 μg/ml), O2 −(IC50 = 30.86 μg/ml), OH (IC50 = 25.05 μg/ml) and ABTS + (IC50 = 30.28 μg/ml). The antimicrobial activity showed that Staphylococcus aureus (26.2 ± 1.32 mm; MIC = 31.25 μg/mL) and Bacillus cereus (24.6 ± 1.15 mm; MIC = 62.5 μg/mL) were the most sensitive organisms and also moderate activity was recorded against all the fungal strains tested. The present study suggests that the wood apple essential oil can be considered as a new and potential source of natural antioxidant and antimicrobial agent.

The mosquito larvicidal activities of different solvent extracts (chloroform, ethyl acetate, and methanol) from the leaves of Coccinia indica were studied. Among the extracts tested, the methanol extract showed the highest larvicidal activity against early fourth instar larvae of Culex quinquefasciatus (LC50 = 142 mg L−1), Aedes aegypti (LC50 = 158 mg L−1) and Anopheles stephensi (LC50 = 161 mg L−1) after 24 h of exposure period. The lowest larval mortality was observed with the ethyl acetate extract with the LC50 values of 927, 872, and 730 mg L−1 against Cx. quinquefasciatus, Ae. aegypti, and An. stephensi, respectively. The chloroform extract showed the moderate larvicidal activity against the mosquito species tested with the LC50 values from 446 to 546 mg L−1. A new triterpene was isolated from the methanol extract using bio-assay guided separation and identified as an oleanolic acid derivative by NMR, IR and mass spectral studies. The compound showed prominent larvicidal activity against Cx. quinquef...

The larvicidal potential of petroleum ether, chloroform, ethyl acetate and methanol extracts of leaves and seeds of four traditionally important Cassia species viz., Senna alata, Senna auriculata, Senna tora and Cassia fistula was studied against the early fourthinstar larvae of two important mosquito vectors, Anopheles stephensi and Aedes aegypti. The leaf and seed extracts of four selected plants at 1000, 500, 250 and 125 ppm caused a considerable mortality in the selected mosquito larvae and the seed extracts were more potent than leaf extracts. Among the tested extracts, the petroleum ether seed extract of C. fistula showed the highest larvicidal activity at LC50 value of 715.11 ppm (12 h), 320.71 ppm (24 h) and at LC90 of 1780.12 ppm (12 h), 954.25 ppm (24 h) against A. aegypti. Similarly, in A. stephensi, highest larvicidal activity was observed on treatment with petroleum ether seed extract of C. fistula at LC50 concentration of 834.74 ppm (12 h), 408.48 ppm (24 h) and at LC90 value of 2079.88 ppm (12 h), 1430.45 ppm (24 h). However, in the case of leaf extracts, the methanol extract of S. tora demonstrated highest activity at LC50 of 973.09 ppm, 659.13 ppm and LC90 of 1870.34 ppm, 1336.39 ppm against A. stephensi after 12 h and 24 h, respectively. The results suggested that the petroleum ether seed extract of Cassia fistula can be used efficiently for controlling the tested mosquito vector species in an eco-friendly manner

The antibacterial activity of the leaf essential oil of Blumea mollis was assayed against 14 clinically isolated bacterial strains on Muller–Hinton Agar medium and Muller–Hinton Agar medium with 5% sheep blood. The essential oil had promising antibacterial activity against all the bacterial strains tested. The highest mean zone of inhibition and lowest values of minimum inhibitory concentration were recorded against methicillin-resistant Staphylococcus aureus followed by beta hemolytic Streptococcus pyogenes. The Gram-positive bacteria were more sensitive than Gram-negative bacteria. Among the bacterial strains tested, Psudomonas aeruginosa was resistant to the essential oil. The results of the present study suggest that the essential oil of B. mollis is one of the new medicinal resources as an antibacterial agent against the bacterial strains tested.

The mangroves Rhizophora lamarkii, Ceriops roxburghiana, Bruguiera gymnorrhiza, Aegiceras corniculatum, and Lumnitzera racemosa were screened for their carbon metabolic pathways by measuring net photosynthetic rate (PN), 13 C discrimination rate, leaf anatomy, titratable acidity, and activities of phosphoenolpyruvate carboxylase, NADH-malate dehydrogenase, alanine aminotransferase, aspartate aminotransferase, and pyruvate phosphate dikinase. The tested mangroves had a well developed succulence, opening of stomata during day time and closure in the night hours, and absence of diurnal fluctuation of organic acids in their leaves which excludes the possibility of these species being CAM plants. Moreover, the leaf anatomy had not exhibited Kranz syndrome. The high values of discrimination against 13 C, low PN, high CO2 compensation concentration, and the activities of aminotransferases in the direction of alanine formation suggest that the species may follow C3 mode of carbon metabolic pathway.

The antibacterial activity of aqueous and methanol extracts of leaves/shoots of five salt marsh halophytes and six mangroves was studied against methicillin resistant, clinical isolates of Staphylococcus aureus. There was a clear comparability between the salt marsh halophytes and mangroves in their antibacterial action. The mangrove plants possessed higher antibacterial potency than the salt marsh halophytes. The highest activity was recorded with the methanol extract of Excoecaria agallocha followed by the methanol extracts of Aegiceras corniculatum, Lumnitzera racemosa and Ceriops decandra. The minimum inhibitory concentration (MIC) values ranged from 0.125 to 4 mg/mL and 1 to 16 mg/mL for methanol and aqueous extracts, respectively. Further separation of active principle from the potent mangrove plant will be useful for the control of drug resistant strains of S. aureus.

Fatty acid methyl ester (FAME) extracts of four halophytic plants, viz. Arthrocnemum indicum, Salicornia brachiata, Suaeda maritima and Suaeda monoica belonging to the family Chenopodiaceae, were prepared and their composition was analyzed by GC-MS. The FAME extracts were also screened for antibacterial and antifungal activities. The GC-MS analysis revealed the presence of more saturated fatty acids than unsaturated fatty acids. Among the fatty acids analyzed, the relative percentage of lauric acid was high in S. brachiata (61.85%). The FAME extract of S. brachiata showed the highest antibacterial and antifungal activities among the extracts tested. The other three extracts showed potent antibacterial and moderate anticandidal activities.

Fatty acids are widely occurring in natural fats and dietary oils and they are known to have antibacterial and antifungal properties. However, little is known on the antibacterial and antifungal properties of the blind-your-eye mangrove (Excoecaria agallocha) and this study for the first time determines the fatty acid composition and the antibacterial and antifungal activities of Fatty Acid Methyl Esters (FAME) of the blind-your-eye mangrove plant found along the coastal areas of south India. Gorduras naturais e óleos são abundantes em ácidos graxos que apresentam atividade antibacteriana e antifúngica. Entretanto, pouco se sabe sobre a atividade antibacteriana e antifúngica de ésteres metílicos de ácidos graxos de mangue "blind-your-eye" (Excoecaria agallocha). Esse estudo relata, pela primeira vez, a composição em ácidos graxos e a atividade antibacteriana e antifúngica de ésteres metílicos de ácidos graxos (FAME) de mangue "blind-your-eye" encontrado ao longo de áreas costeiras do sul da India.

The vector-borne diseases caused by mosquitoes are one of the major health problems in many countries especially in tropical and sub-tropical countries. The resistance of mosquitoes to synthetic chemicals and environmental toxicity created by the chemicals raised the demand for finding of alternate natural molecules that control mosquito. In the present study, the compound 1, 2-Benzenedicarboxylic acid, mono (2-ethylhexyl) ester was isolated from the ethyl acetate extract of leaves of Clausena anisata and it was identified by various spectral studies. The larvicidal potential of the isolated compound was evaluated against early 4 th instar larvae of Culex quinquefasciatus , Aedes aegypti and Anopheles stephensi. The compound exhibited 100% larval mortality against A. aegypti and A. stephensi at 40 ppm with LC 50 values of 8.944 and 9.230 ppm respectively. The molecule also showed the LC 50 value of 12.067 ppm against C . quinquefasciatus. The molecule isolated from C. anisata can be better explored for the control of mosquito population after toxicological evaluation.

The effect of seaweed liquid fertilizers (SLF) of Sargassum wightii and Caulerpa chemnitzia on growth and biochemical constituents of Vigna sinensis was studied. The seeds soaked with aqueous extract of seaweeds performed better when compared to the water soaked controls. Hundred per cent germination was recorded both in aqueous extract soaked and water soaked treatments. The low concentration (20%) of aqueous extracts of S. wightii and C. chemnitzia promoted the seedling growth including the parameters of shoot length (15.87, 14.13 cm/seedling), root length (6.42, 5.38 cm/seedling), fresh weight (4.017, 4.012 g/seedling) and dry weight (0.878, 0.865 g/seedling), chlorophyll (1.599, 1.491 mg g −1 fr. wt.), carotenoids (0.899, 0.875 mg g −1 fr. wt.), protein content of shoot (3.956, 3.474 mg g −1 fr. wt.) and root (2.926, 2.890 mg g −1 fr. wt.), amino acid content of shoot (1.447, 1.429 mg g −1 fr. wt.) and root (0.698, 0.680 mg g −1 fr. wt.), reducing sugar content of shoot (6.426, 6.233 mg g −1 fr. wt.) and root (5.118, 5.103 mg g −1 fr. wt.), total sugar content of shoot (11.846, 11.350 mg g −1 fr. wt.) and root (10.368, 10.102 mg g −1 fr. wt.), α-amylase (1.927, 1.819 μg min −1 mg −1 protein) and β-amylase (1.730, 1.617 μg min −1 mg −1 protein) activities in V. sinensis . Among the two seaweeds tested, S. wightii exhibited better responses.

In the present investigation, larvicidal potential of hexane, choloroform, ethyl acetate, acetone, and methanol extracts of seven aromatic plants, viz., Blumea mollis, Chloroxylon swietenia, Clausena anisata, Feronia limnonia, Lantana camera, Plectranthus amboinicus, and Tagetes erecta were screened against Culex quinquefasciatus, Aedes aegypti, and Anopheles stephensi. The larval mortality was observed after 12 and 24 h of exposure period. The results revealed that all the extracts showed varied levels of larvicidal activity against the mosquito species tested. However, the ethyl acetate extract of Chloroxylon swietenia showed the remarkable larvicidal activity against C. quinquefasciatus, Ae. aegypti, and An. stephensi. After 12 h of exposure period, the larvicidal activity was LC50 = 194.22 and LC90 = 458.83 ppm (C. quinquefasciatus), LC50 = 173.04 and LC90 = 442.73 ppm (Ae. aegypti), and LC50 = 167.28 and LC90 = 433.07 ppm (An. stephensi), and the larvicidal activity after 24-h exposure period was LC50 = 94.12 and LC90 = 249.83 ppm (C. quinquefasciatus), LC50 = 80.58 and LC90 = 200.96 ppm (Ae. aegypti), and LC50 = 76.24 and LC90 = 194.51 ppm (An. stephensi). The larvicidal potential of other plant extracts were in order of ethyl acetate extract of Clausena anisata > methanol extract of P. amboinicus > acetone extract of F. limonia > methanol extract of T. erecta > methanol extract of B. mollis > and methanol extract of L. camera. The results of the present study offer a possible way for further investigations to find out the active molecule responsible for the activity.

Objective To identify the chemical composition and larvicidal activity of Acorus calamus ( A. calamus ) rhizome essential oil against the filarial vector mosquito, Culex quinquefasciatus ( Cx. quinquefasciatus ). Methods Essential oil was isolated by hydro-distillation and the chemical composition of the oil was analysed by gas chromatography and gas chromatography mass spectroscopy analysis. The larvicidal activity of the essential oil was analysed at different concentrations, viz ., 12.5, 25.0, 50.0, 100.0 and 200.0 mL/L. Early 4th instar larvae were used for the larvicidal assay. The larval mortality was calculated after 24 h of the exposure. Results The gas chromatography and gas chromatography mass spectroscopy analysis showed that the essential oil extracted from the rhizome of A. calamus contained 20 chemical compounds representing about 99.99% of the total oil. Beta-asarone (33.36%), cis -beta-terpineol (23.44%), limonene (13.08%), carvone (5.64%) and amyl isovalerate (4.92%) were identified as the major chemical compounds. The essential oil had promising larvicidal effect against the early 4th instar larvae of Cx. quinquefasciatus with LC 50 value of 63.43 mL/L and LC 90 value of 145.95 mL/L. Conclusion The essential oil of A. calamus rhizome can be used as a natural larvicidal agent against the larvae of filarial vector mosquito, Cx. quinquefasciatus .

India has 3% of the world’s mangrove area [1]. In Tami Nadu, it has an area of 21 sq. km, and the Pichavaram mangrove is one of the recognized tropical ecosystems because it is used in folkl medicine for the treatment of several diseases [2, 3]. Fatty acids are the constituents of all plant cells, where they function as membrane components, storage products, metabolites, and as a source of energy [4], and they also important nutrient substances and metabolites in living organisms [5]. The aim of this investigation was to determine the fatty acid composition of some mangroves by gas chromatography. The fatty acid composition of eight mangrove species was determined, and their relative percentage are presented in Table 1. The fatty acids, viz., myristic, pentadecanoic, palmitic, heptadecanoic, oleic, linoleic, and linolenic acids, were found in all the plant species tested. When compared to other tested plants, the highest relative percentage of oleic acid (16.62%), linolenic acid (16.32%), arachidic acid (2.06%), and pentadecanoic acid (1.53%) were detected in A. officinalis; myristic acid (8.58%) and heptadecanoic acid (1.27%) in B. cylindrica; tridecanoic acid (0.76%) in C. decandra; linoleic acid (12.03%), behenic acid (1.38%), and heneicosanoic acid (0.03%) in A. corniculatum; palmitic acid (61.45%) in L. racemosa; lauric acid (38.58%) and stearic acid (1.76%) were detected in A. ilicifolius. Lauric acid has been found in all the plant species tested except A. officinalis; tridecanoic acid was not found in R. apiculata, R. mucronata, and A. corniculatum; nonadecanoic acid was found only in B. cylindrica and L. racemosa. Arachidic and behenic acids were not found in A. corniculatum and A. ilicifolius, respectively. Analysis of the fatty acid composition by gas chromatography revealed the presence of higher amounts of saturated fatty acids than the unsaturated fatty acids. The highest relative percentage of palmitic acid (61.5%) was detected in L. recemosa. Palmitic acid seems to be a major fatty acid common to wax esters of A. officinalis, B. gymnorhiza, A. ilicifolius, R. mucronata

Responses of Ceriops roxburghiana Arn. leaves to the sodium chloride, applied at different concentrations (ranging from 100 to 600 mM), has been evaluated. Total amino acid content decreased with increasing NaCl concentration, while the protein content increased significantly up to 400 mM concentration and decreased thereafter. Total sugar content decreased at concentrations beyond 400 mM. Proline and glycine betaine were accumulated with increasing NaCl concentration. Protease and ATPase activities were increased whereas proline oxidase activity were decreased with increasing salinity. Peroxidase and malate dehydrogenase (NADH-MDH) activities did not significantly differ under various NaCl concentrations.

Summary Different solvent extracts of leaves of Achyranthes aspera , Aegle marmelos , Cleistanthus collinus , Curcuma aromatica and Strychnos nux-vomica were screened against dermatophytes viz. , Trichophyton mentagrophytes , T. rubrum , Microsporum gypseum , M. canis and Epidermophyton floccossum var. nigricans . The mean zones of inhibition were between 7.1 and 26.5 mm. Minimum inhibitory concentrations (MIC) and minimum fungicidal concentrations (MFC) were from 7.81 to 500 and from 15.62 to 1000 μg/mL respectively. The highest mean zone of inhibition (26.5 mm), the lowest MIC value (7.81 μg/ml) and the lowest MFC (15.62 μg/ml) were observed in ethyl acetate extract of A. aspera against T. rubrum . The standard antifungal drug ketoconazole (10 μg/disc) was used as the positive control and mean zones of inhibition were from 23 to 29 mm. Further separation of active principle from ethyl acetate extract of A. aspera is under progress.

In the present investigation, the leaf essential oil of Feronia limonia was evaluated for chemical constituents and mosquito larvicidal activity against the larvae of Anopheles stephensi, Aedes aegypti and Culex quinquefasciatus. GC and GC-MS analyses revealed that the essential oil contain 51 compounds. Estragole (34.69 %) and β-pinene(23.59 %) were identified as the major constituents followed by methyl (Z)-caryophyllene (11.05 %), eugenol (6.50 %), linalool (3.97 %), phytol (3.27 %), sabinene (2.41 %) and limonene (2.27 %). Larval mortality was observed after 12 and 24 h of exposure period. The oil showed remarkable larvicidal activity against A. stephensi (LC(50) = 38.93 and LC(90) = 108.64 ppm (after 12 h); LC(50) = 15.03 and LC(90) = 36.69 ppm (after 24 h)), A. aegypti (LC(50) = 37.60 and LC(90) = 104.69 ppm (after 12 h); LC(50) = 11.59 and LC(90) = 42.95 ppm (after 24 h)) and C. quinquefasciatus (LC(50) = 52.08 and LC(90) = 124.33 ppm (after 12 h); LC(50) = 22.49 and LC(90) = 60.90 ppm (after 24 h)). Based on the results, the essential oil of F. limonia can be considered as a new source of larvicide for the control of vector mosquitoes.

Response of Sesuvium portulacastrum L., to the elogenous addition of sodium chloride (NaCl), applied at different concentrations ranging from 100 to 900 mM was evaluated. Leaf area, shoot and root weight of the treated plants were increased significantly. Total nitrogen (N) content of leaves, stem and root was significantly increased up to 600 mM NaCl, and thereafter declined moderately. Accumulation of potassium (K), and calcium (Ca) were exponentially increased with NaCl treatment as also observed in the case of N. Sodium content of shoot and roots of S. portulacastrum increased significantly with increasing NaCl concentrations. Certain essential elements like copper (Cu), iron (Fe), manganese (Mn) and zinc (Zn) were also accumulated in all plant parts significantly, up to 600 mM. However, due to high salinization, growth and development of plants inhibited markedly. Furthermore, elemental concentration decreased beyond 600 mM level of NaCl. Due to aging and senescence, marked changes in leaf a...

Certain organic constituents, amino acids, protein, proline, glycinebetaine, sugars, and starch in the leaves of Sesuvium portulacastrum, which was grown under varying levels of sodium chloride (NaCl) was determined. Total amino acids lowered at increasing levels of NaCl while the protein content increased moderately up to 600 mM and thereafter increased and decreased, respectively; however, 600 mM level of NaCl significantly differed from the untreated control plants. The concentration of total sugars declined with the increasing levels of exogenous addition of NaCl up to 600 mM. Starch content increased significantly up to 600 mM NaCl and thereafter declined slightly. Proline and glycinebetaine contents were accumulated with the corresponding increase of salinization.

The anti-plasmodial activity of different solvent extracts of Adhatoda vasica (root), Caesalpinia pulcherrima (leaf), Carica papaya (pulp), Erythroxylum monogynum (leaf), Lantana camara (whole plant), Ocimum sanctum (root) and Phyllanthus niruri (whole plant) were studied against Plasmodium falciparum. Of the 35 extracts tested, seven extracts showed good anti-plasmodial activity. Methanol extract of C. pulcherrima showed the lowest IC50 value (10.96 μg/mL) followed by methanol extract of A. vasica (IC(50)=11.1 μg/mL), chloroform extract of O. sanctum (IC(50)=11.47 μg/mL), methanol extract of E. monogynum (IC(50)=12.23 μg/mL), acetone extract of C. pulcherrima (IC(50)=12.49 μg/mL), methanol extract of O. sanctum and acetone extract of A. vasica (IC(50)=14.04 μg/mL). The results of the present study justify the use of these medicinal plants in traditional practice, and also, a further study on the isolation of anti-plasmodial molecules from their active crude extracts is in progress.

The vector-borne diseases caused by mosquitoes are one of the major health problems in many countries especially in tropical and sub-tropical countries. The resistance of mosquitoes to synthetic chemicals and environmental toxicity created by the chemicals raised the demand for finding of alternate natural molecules that control mosquito. In the present study, a crystalline compound methyl-p-hydroxybenzoate was isolated from the methanol extract of Vitex trifolia leaves and it was identified by (1)H and (13)C NMR and single crystal X-ray diffractometer. The larvicidal potential of the isolated compound was evaluated against early 4th instar larvae of Culex quinquefasciatus and Aedes aegypti. The compound exhibited 100% larval mortality of both the mosquitoes at 20 ppm with LC(50) values of 5.77 and 4.74 ppm against C. quinquefasciatus and A. aegypti, respectively. The methyl-p-hydroxybenzoate, which is reported for the first time to our best of knowledge from V. trifolia can be better explored for the control of mosquito population.

Essential oil of Plectranthus amboinicus was studied for its chemical composition and larvicidal potential against the malarial vector mosquito Anopheles stephensi. Totally 26 compounds were identified by GC and GC-MS. The major chemical compounds were carvacrol (28.65%) followed by thymol (21.66%), α-humulene (9.67%), undecanal (8.29%), γ-terpinene (7.76%), ρ-cymene (6.46%), caryophyllene oxide (5.85%), α-terpineol (3.28%) and β-selinene (2.01%). The larvicidal assay was conducted to record the LC(50) and LC(90) values and the larval mortality was observed after 12 and 24 h of exposure period. The LC(50) values of the oil were 33.54 (after 12 h) and 28.37 ppm (after 24 h). The LC(90) values of the oil were 70.27 (after 12 h) and 59.38 ppm (after 24 h). The results of the present study showed that the essential oil of P. amboinicus is one of the inexpensive and eco-friendly sources of natural mosquito larvicidal agent to control/reduce the population of malarial vector mosquito.

The essential oil from the leaves of Blumea mollis was extracted and the chemical constituents and the larvicidal against Culex quinquefasciatus effects studied. The analyses of gas chromatography (GC) and GC-mass spectroscopy (GC-MS) revealed that the leaf essential oil of B. mollis contained 39 compounds, and the major chemical compounds identified were linalool (19.43%), gamma-elemene (12.19%), copaene (10.93%), estragole (10.81%), Allo-ocimene (10.03%), gamma-terpinene (8.28%) and Allo-aromadendrene (7.44%). The essential oil had significant toxic effect against early fourth-instar larvae of C. quinquefasciatus with LC50=71.71 and LC90=143.41 ppm. The results could be useful in search of newer, safer and more effective natural larvicidal agent against C. quinquefasciatus.

The larvicidal activity of fatty acid methyl ester (FAME) extracts of Vitex altissima, Vitex negundo and Vitex trifolia was studied against early fourth-instar larvae of Culex quinquefasciatus. The fatty composition was analysed by gas chromatography. The highest percentage of lauric acid, palmitic acid, stearic acid, oleic acid and linolenic acid were recorded in V. negundo. The highest percentage of linolenic acid was recorded in V. trifolia. The FAME extract of V. trifolia showed the highest larvicidal activity with an LC50 value of 9.25 ppm followed by V. altissima (14.82 ppm) and V. negundo (18.64 ppm).

The essential oil from the leaves of Feronia limonia was extracted and the chemical constituents and antibacterial activity were studied. The GC and GC-MS analyses revealed that the leaf essential oil of F. limonia contained fourteen compounds representing about 98.4% of the total oil. The major chemical compounds identified were Eudesma-4 (14).11-dine (46.3%), carvacrol (29.6%) and 1,5-cyclodecandine (13.4%). The essential oil was screened for its antibacterial activity against different clinically isolated Gram positive and Gram negative bacterial strains by disc diffusion and minimum inhibitory concentration assay. The essential oil exhibited moderate antibacterial activity against all the tested bacterial strains with MIC values ranging from 125 to 500 μg/mL except Proteus mirabilis.

The early fourth instar larvae of Culex quinquefasciatus, reared in the laboratory were used for larvicidal assay with leaf extracts of Vitex negundo, Vitex trifolia, Vitex peduncularis and Vitex altissima. The methanol extracts of the four species possessed varying levels of larvicidal nature. The highest larvicidal activity was found with the extract of V. trifolia (LC(50) = 41.41 ppm) followed by V. peduncularis (LC(50) = 76.28 ppm), V. altissima (LC(50) = 128.04 ppm) and V. negundo (LC(50) = 212.57 ppm).

The plant growth, net photosynthetic rate (PN), intercellular CO2 concentration (ci), and dry matter production of Ceriops roxburghiana Arn. were significantly increased with increasing salinity from 0 to 400 mM NaCl. At 600 mM NaCl, shoot and root lengths, and dry mass were significantly depressed with respect to control. Absence of diurnal fluctuation of concentrations of organic acids, and the low activity of phosphoenolpyruvate carboxylase and high activity of ribulose-1,5-bisphosphate carboxylase confirmed the operation of C3 pathway in Ceriops even at increasing salinity.

The water and methanolic extracts of Syzygium jambolanum seeds were examined for antibacterial and antifungal activity in vitro using the disc diffusion method, minimum inhibitory concentration, minimum bactericidal concentration and minimum fungicidal concentration. Activity against gram positive bacteria (Bacillus subtilis, Staphylococcus aureus), gram negative bacteria (Salmonella typhimurium, Pseudomonas aeruginosa, Klebsiella pneumoniae and Escherichia coli) and fungal strains (Candida albicans, Cryptococcus neoformans, Aspergillus flavus, Aspergillus fumigatus, Aspergillus niger, Rhizopus sp., Trichophyton rubrum, Trichophyton mentagrophytes and Microsporum gypseum) is discussed.

The effect of seaweed liquid fertilizer (SLF) of Sargassum myriocystum on germination, growth and biochemical constituents of Vigna mungo was studied. Different concentrations (5%, 10%, 25%, 50% and 75%) of SLF were prepared using distilled water. A total of 100 seeds were soaked for each SLF concentration for a 24-h period and were later placed in various Petri plates and watered regularly. Water-soaked seeds were used as controls. Seed germination was 98% for the 10% SLF soaked seeds. Similarly, shoot length (21.13 cm seedling-1), root length (12.19 cm seedling-1), fresh weight and dry weight (3.910 and 0.320 g seedling-1) recorded at 10% concentration of S. myriocystum treated seedlings were the highest. Besides, the chlorophyll (0.547 mg g-1 fr. wt.) and carotenoid (0.359 mg g-1 fr. wt.) contents in leaves recorded at 10% SLF soaked seedlings were the highest. The 10% SLF treated seedlings showed the highest content of protein (1.898 and 1.508 mg g–1 fr. wt.), amino acid (0.370 and 0.306 mg g–1 fr. wt.), reducing sugar (6.031 and 3.448 mg g-1 fr. wt.), total sugar (8.414 and 7.055 mg mL-1 fr. wt.), alpha-amylase activity (1.403 and 1.380 μg min-1 mg-1 protein) and beta-amylase activity (1.099 and 1.029 μg min-1 mg-1 protein) of shoots and roots respectively. The seaweed extract showed better response at lower concentration while higher concentrations of seaweed extract showed a decreasing trend. Se estudió el efecto de un fertilizante líquido de algas marinas (SLF) preparado con Sargassum myriocystum sobre la germinación, crecimiento y componentes bioquímicos de Vigna mungo. Se introdujeron 100 semillas durante 24 h en diferentes concentraciones (5%, 10%, 25%, 50% y 75%) de SLF (en agua el control), se colocaron en placas de Petri y se regaron con regularidad. La germinación fue del 98% para las semillas introducidas en SLF al 10%. La longitud de los brotes (21,13 cm plántula-1), longitud de la raíz (12,19 cm plántula-1), peso fresco y peso seco (3,910 y 0,320 g plántula-1), clorofila (0,547 mg g-1 peso fresco) y contenido en carotenoides (0,359 mg g-1 peso fresco) fueron las mayores en esta concentración. Adicionalmente, esta concentración produjo el mayor contenido de proteínas (1,898 y 1,508 mg g-1 peso fresco), aminoácidos (0,370 y 0,306 mg g-1 peso fresco), azúcares reductores (6,031 y 3,448 mg g-1 peso fresco), azúcares totales (8,414 y 7,055 mg g-1 peso fresco), actividad alfa-amilasa (1,403 y 1,380 μg min-1 mg-1 proteína) y actividad beta-amilasa (1,099 y 1,029 μg min-1 mg-1 proteína) de brotes y raíces, respectivamente. Por tanto, el SLF produjo una mejor respuesta a bajas concentraciones, mientras que con concentraciones más altas se obtuvo una respuesta decreciente.

Growth regulators are used in tea plantations from planting to productivity. Paclobutrazol at 500 ppm applied on foliage, 1 month after planting, promotes lateral production, besides feeder root proliferation. Triacontanol at 2 ppm applied in mature tea improves productivity through enhanced photosynthesis, favorable partition of assimilates, and water-use efficiency. Hydrogen cyanamide applied on the pruned frame at 0.5% improves budbreak. Antitranspirants based on long-chain polymers impart drought-tolerance in young and mature tea. Thus, use of PGR for cost-effective management of tea plantations, without affecting the quality of made tea or bush health, has been standardized.