HPTLC analysis of Scoparia dulcis Linn (Scrophulariaceae) and its larvicidal potential against dengue vector Aedes aegypti

This study evaluates the larvicidal activity of Scoparia dulcis aqueous extract against dengue vector and determines its major chemical components. The extract was tested at various concentrations ranging from 0.1 to 2 mg/mL against Aedes aegypti larvae. The extracts displayed significant larvicidal efficacy against Ae. aegypt species after 24 h exposure revealing LC₅₀ of 3.3835 (mg/mL) and LC₉₀ of 5.7578 (mg/mL). Finger printing profile carried out by CAMAG automatic TLC sample applicator programmed through WIN CATS software revealed peaks with different R_f values for three different volumes injected: 16, 15 and 18 peaks were spotted for 3, 6 and 9 μL, respectively. Ascending order of R_f values was also ascertained for each peak recorded. This study clearly signifies that S. dulcis extract contains numerous compounds that are known to have larvicidal properties which clearly substantiates its efficacy on Ae. aegypti larvae.     

Comparative efficacy of Eucalyptus globulus (Labill) hydrodistilled essential oil and temephos as mosquito larvicide

Abstract

In this study Eucalyptus globulus essential oil was tested on major mosquito species and toxicity was compared with temephos. Mortality was calculated after 24?h and 48?h post treatment. In 24?h treatment essential oil show strong larvicidal activity with LC₅₀ and LC₉₀ values were 30.198ppm, 103.389ppm for Anopheles stephensi, 13.578ppm, 106.755ppm for Aedes aegypti; and, 7.469ppm, 32.454ppm for Culex quinquefasciatus and 48?h post treatment LC₅₀ and LC₉₀ values were, 12.576, 49.380ppm for Anopheles stephensi, 7.926, 34.470ppm for Aedes aegypti and 4.408, 21.048ppm for Culex quinquefasciatus. Chemical composition of essential oil using GC-MS and FT-IR analysis shows the presence of 1,8-cineol, (71.7%); α-pinene, (9.14%) as a major compounds. Our findings suggest that essential oil from Eucalyptus globulus leaves can be used for control of mosquito larvae.     

Chemical composition and larvicidal activity of Zanthoxylum armatum against diamondback moth,Plutella xylostella

The diamondback moth, Plutella xylostella (L.) (Lepidoptera: Yponomeutidae) is the most serious pest of cruciferous crops grown in the world causing economic yield loss. Several synthetic insecticides have been used against P. xylostella but satisfactory control was not achieved due to development of resistance to insecticides. Therefore, the present study was carried out to screen different fractions of Zanthoxylum armatum for their insecticidal activities against second instar larvae of P. xylostella. Results indicate, all the fractions showed activity to P. xylostella. However, n-hexane fraction of Z. armatum showed maximum larvicidal activity with minimum LC₅₀ value of 2988.6 ppm followed by ethanol (LC₅₀ = 12779.7 ppm) and methanol fraction (LC₅₀ = 12908.8 ppm) whereas chloroform fraction was least toxic (LC₅₀ = 16750.6 ppm). The GC–MS analysis of n-hexane fraction of leaf extract showed maximum larvicidal activity, which may be due to two major compounds i.e. 2-undecanone (19.75%) and 2-tridecanone (11.76%).     

Aedes aegypti larvicide from the ethanolic extract of Piper nigrum black peppercorns

Due to unavailability of a vaccine and a specific cure to dengue, the focus nowadays is to develop an effective vector control method against the female Aedes aegypti mosquito. This study aims to determine the larvicidal fractions from Piper nigrum ethanolic extracts (PnPcmE) and to elucidate the identity of the bioactive compounds that comprise these larvicidal fractions. Larvicidal assay was performed by subjecting 3rd to 4th A. aegypti instar larvae to PnPcmE of P. nigrum. The PnPcmE exhibited potential larvicidal activity having an LC₅₀ of 7.1246 ± 0.1304 ppm (mean ± Std error). Normal phase vacuum liquid chromatography of the PnPcmE was employed which resulted in five fractions, two of which showed larvicidal activity. The most active of the PnPcmE fractions is PnPcmE-1A, with an LC₅₀ and LC₉₀ of 1.7101 ± 0.0491 ppm and 3.7078 ppm, respectively. Subsequent purification of PnPcmE-1A allowed the identification of the larvicidal compound as oleic acid.     

Phenolic compounds: antioxidant and larvicidal potential of Smilax brasiliensis Sprengel leaves

Abstract

Smilax brasiliensis is a medicinal species of the Brazilian Cerrado. The extract and fractions of this plant were analysed by LC-DAD-MS. Identified constituents included glycosylated and non-glycosylated flavonoids, especially quercetin, and phenylpropanoids, such as chlorogenic acids. The antioxidant activity was significantly more pronounced for the methanol extract and fractions than that of the commercial antioxidant 2,6-di-tert-butyl-4-methylphenol (BHT). Maximum larvicidal activity of 85.83% was recorded in the dichloromethane fraction (LC₅₀ = 469.78?µg mL^?1). The methanol extract and fractions presented low toxicity to larvae of the shrimp brine Artemia salina, indicating selectivity for C. quinquefasciatus. These results contribute to the phytochemical study of S. brasiliensis. These compounds were identified for the first time in this species and encourage additional work on the isolation of compounds present in the extract and fractions of S. brasiliensis to evaluate the possibility of using them as natural sources of antioxidants, since cytotoxic effects were not demonstrated.     

Chemical composition and insecticidal activities of essential oils against diamondback moth,Plutella xylostella (L.) (Lepidoptera: Yponomeutidae)

Five Himalayan plants namely, Acorus calamus, Cedrus deodara, Aegle marmelos, Tagetes minuta and Murraya koenigii were used for the extraction of essential oils through hydrodistillation and the major volatile constituents as identified by GC and GC–MS techniques were β-asarone (91.1%), β-himachalene (45.8%), limonene (59.5%), Z-ocimene (37.9%) and α-pinene (54.2%), respectively. Essential oils were tested for their insecticidal properties against larvae of diamondback moth, Plutella xylostella (L.) (Lepidoptera: Yponomeutidae). Results showed that A. calamus was most toxic (LC_50?=?0.29 mg mL^?1) to P. xylostella followed by C. deodara (LC_50?=?1.08 mg mL^?1) and M. koenigii (LC_50?=?1.93 mg mL^?1) via residual toxicity bioassay. Per cent feeding deterrence index and growth inhibition was significantly higher in A. calamus (42.20 and 68.55, respectively) followed by C. deodara (35.41 and 52.47). In repellent activity studies, C. deodara showed high repellence (64.76%) followed by A. calamus (55.05%).     

Anti-inflammatory activity of saponins from roots of Impatiens parviflora DC.

Abstract

Two triterpene saponins (IPS-1, IPS-2) for the first time were isolated from the roots of Impatiens parviflora DC. (Balsaminaceae). Their anti-inflammatory activity was evaluated by means of two in vitro models: anti-hyaluronidase and anti-denaturation assays. Both saponins were shown to be potent hyaluronidase inhibitors that affect the enzyme in a dose-dependent manner. The anti-hyaluronidase effect of IPS-2 (IC₅₀?=?286.7?µg/mL) was higher than that of the reference drug: escin (IC₅₀?=?303.93?µg/mL). Both saponins protected bovine serum albumin from heat-induced denaturation in a dose-dependent manner. IPS-1 demonstrated higher anti-denaturation effect (IC₅₀?=?86.7?µg/ml) than IPS-2 (IC₅₀?=?109.76?µg/mL) or the standard drug: acetylsalicylic acid (IC₅₀?=?262.22?µg/mL). In conclusion, potent activity of IPS-1, IPS-2 in both in vitro assays shows that saponins from I. parviflora have anti-inflammatory activity. The obtained results allow to suggest that such compounds may be beneficial in inflammatory conditions, especially associated with excessive degradation of hyaluronic acid.     

Chemical composition,antioxidant, antimicrobial and anticancer activities of the essential oil from the rhizomes of Zingiber striolatum Diels

Abstract

The chemical composition and biological activities of the essential oil (EO) from the rhizomes of Zingiber striolatum Diels were reported for the first time. Forty-five compounds were identified, and represented 95.7% of the total composition of the EO. The predominant components of the EO were β-phellandrene (24.0%), sabinene (17.3%), β-pinene (11.4%), geranyl linalool (8.6%), terpinen-4-ol (8.3%), α-pinene (5.6%) and crypton (4.5%). The EO revealed a weak DPPH and ABTS radical-scavenging activity. The EO exhibited significant antimicrobial activity with the inhibition zones (12.86–24.62?mm) and MIC (0.78–3.12?mg/mL) against Enterococcus faecalis, Staphylococcus aureus, Pseudomonas aeruginosa, Escherichia coli, Candida albicans. The EO showed significant cytotoxicity against human leukemic (K562), lung cancer (A549) and prostatic carcinoma (PC-3) cell lines with the IC₅₀ values of 29.67, 48.87 and 86.05?μg/mL, respectively. Thus, the EO could be regarded as a bioactive natural product with potential for utilization in the cosmetic and pharmaceutical industry.     

Chemical constituents and cytotoxic activity from the wood-decaying fungus Xylaria sp. SWUF08-37

Abstract

A new cyclic pentapeptide, pentaminolarin (1), and a new cytochalasin, xylochalasin (2), along with thirteen known compounds (3–15) were isolated from the wood-decaying fungus Xylaria sp. SWUF08-37. The absolute configurations of 1 were determined by a combination of Marfey’s method and TDDFT ECD calculation and the absolute configurations of 2 were established by TDDFT ECD calculation. Compound 12 showed moderate cytotoxicity against HeLa (IC₅₀?=?19.60?µg/mL), HT29 (IC₅₀?=?17.31?µg/mL), HCT116 (IC₅₀?=?14.28?µg/mL), MCF-7 (IC₅₀?=?15.38?µg/mL), and Vero (IC₅₀?=?24.97?µg/mL) cell lines by MTT assay. Compounds 1 and 2 showed slight cytotoxicity against all tested cancer cell lines.     

Antiglycation,antioxidant, and cytotoxic activities of Uvaria chamae root and essential oil composition

Abstract

Uvaria chamae (Annonaceae), is an essential oil bearing plant; the root is acclaimed as an effective remedy for folkloric diabetic therapy. The root extracts were evaluated for composition, antiglycation, antioxidant, and cytotoxicity. Flavonoids, cardiac glycosides, and tannins were relatively high in the alcohol extract; benzyl benzoate (23.3%), dimethoxy-p-cymene (14.2%), τ-cadinol (12.1%), and methyl thymol (8.7%) predominated the constituents identified by gas chromatography (GC) and gas chromatography-mass spectrometry (GC-MS). The ethanol extract demonstrated significant antiglycation activity (IC₅₀, 1.12?mg/mL), and cytotoxicity to brine shrimp (LC₅₀, 25.01?µg/mL). The extract (IC₅₀, 8.0?µg/mL; absorbance 0.531, 100?µg/mL) also exhibited better antioxidant effects compared with the essential oil (IC₅₀, 50.0?µg/mL; absorbance 0.292, 100?µg/mL) using 2,2-diphenyl-1-picrylhydrazyl radical and ferric reducing power assays respectively. U. chamae root possess antiglycation effect, and may also reduce oxidative stress in patients with diabetes; its antiglycation effect, oil composition, and cytotoxicity are reported for the first time.

     

Synthesis of 3,5-Dichloro-4-(1,1,2,2-tetrafluoroethoxy)phenyl Containing 1,2,3-Thiadiazole Derivatives via Ugi Reaction and Their Biological Activities

A series of novel 3,5‐dichloro‐4‐(1,1,2,2‐tetrafluoroethoxy)phenyl containing 4‐methyl‐1,2,3‐thiadiazole derivatives were designed and synthesized via Ugi reaction. Their structures were confirmed by IR, ¹H NMR, ¹³C NMR and high‐resolution mass spectroscopy. The preliminary bioassay results indicated that some title compounds had good fungicide activity at 50 µg/mL; most of the compounds presented a certain degree of direct inhibition activity, good inactivation and curative activity against tobacco mosaic virus at 500 µg/mL and 100 µg/mL; some compounds showed good larvicidal activity against Plutella xylostella L. at 200 µg/mL and excellent larvicidal activities against Culex pipiens pallens at 2 µg/mL.     

Chemical composition,antimicrobial and antioxidant activities of the essential oil of Psammogetoncanescens

This study reports the chemical composition, antimicrobial activity and antioxidant properties of Psammogeton canescens essential oil (EO) and its main compounds. The EO was obtained from the aerial parts of P. canescens by hydrodistillation and analysed by using GC/MS. The main constituent was β-bisabolene (25%), followed by α-pinene (20%), apiole (15.34%), γ-terpinene (7.34%), p-cymene (5.35%), β-pinene (5.41%), camphene (5.12%), dill apiole (5%), myrcene (4.54%), colchicine (0.56), sylvestrene (0.56%), β-caryophyllene (0.45%), caryophyllene oxide (0.43%), (Z)-β-farnesene (0.32%), cembrene (0.21%), folic acid (0.21%), germacrene D (0.14) and β-sesquiphellandrene (0.13). β-Bisabolene exhibited strong antioxidant activity (14 ± 0.8 μg/mL). The EO of P. canescens was particularly active against Candida albicans and Escherichia coli, with the lowest minimum inhibitory concentration and minimum bactericidal/fungicidal concentration values. In conclusion, these results support the use of the EO and its main compounds for their antioxidant properties and antimicrobial activity.     

Chemical composition and biological activities of Iranian Achillea wilhelmsii L. essential oil: a high effectiveness against Candida spp. and Escherichia strains

In the case of Achillea wilhelmsii, 30 compounds were identified representing 94.48% of the total oil with a yield of 0.82% w/w. The major constituents of the oil were described as α-thujene (6.11%), α-pinene (5.11%), sabinene (5.23%), p-cymene (7%), 1,8-cineole (6%), linalool (10%), camphor (8.43%), thymol (18.98%) and carvacrol (20.13%). A. wilhelmsii oil exhibited higher antibacterial and antifungal activities with a high effectiveness against Escherichia coli and Candida albicans with the lowest minimum inhibitory concentration and minimum bactericidal concentration/minimum fungicidal concentration value (2 ± 0.0–2 ± 0.0 g/mL, 1 ± 0.5–1 ± 0.5 g/mL), respectively. Results showed that A. wilhelmsii oil exhibits a higher activity in each antioxidant system with a special attention for β-carotene bleaching test (IC₅₀: 19 μg/mL) and reducing power (EC₅₀: 10 μg/mL). Antioxidant activity-guided fractionation of the oil was carried out by TLC-bioautography screening and fractionation resulted in the separation of main antioxidant compounds which were identified as thymol (65%) and carvacrol (19%). In conclusion, these results support the use of the essential oil and its main compounds for their antioxidant properties and antimicrobial activity.     

Effect of Carum copticum essential oil on growth and aflatoxin formation by Aspergillus strains

The objectives of this study were to determine the antiaflatoxin B₁ activity in vitro of the essential oil (EO) extracted from the seeds of Carum copticum and to evaluate its antifungal activity in vivo as a potential food preservative. The C. copticum EO exhibited noticeable inhibition on dry mycelium and synthesis of aflatoxin B₁ (AFB₁) by Aspergillus flavus, completely inhibiting AFB₁ production at 4 μL/mL. C. copticum EOs showed the lowest percentages of decayed cherry tomatoes for all fungi compared with the control at 100 μL/mL with values of 5.01 ± 67% for A. flavus and 5.98 ± 54% for Aspergillus niger. The results indicated that the percentage of infected fruits is significantly (p < 0.01) reduced by the EO at 16°C for 30 days. In this case, the oil at 100 μL/mL concentration showed the highest inhibition of fungal infection with a value of 80.45% compared with the control. Thus, the EO of dill could be used to control food spoilage and as a potential source of food preservative.     

A multi-pumping flow system with on-line photochemical conversion and improved sensitivity for phosphorus fractionation in freshwaters

A flow-based procedure with solenoid micro-pumps was developed for phosphorus fractionation (dissolved organic and inorganic phosphorus) in freshwaters. The spectrophotometric detection was based on the formation of molybdenum blue and the organic species were on-line photo-converted to orthophosphate. The analytical response was linear within 10 and 75?µg?L^?1 with a detection limit of 2.0?µg?L^?1 (99.7% confidence level). Coefficient of variation of 1.8% (50?µg?L^?1 P, n?=?20) and sampling rate of 40 determinations per hour were achieved. Per determination, 160?µg (NH₄)₆Mo₇O₂₄, 10?µg SnCl₂, 640?µg K₂S₂O₈ and 10?mg NaOH were consumed, generating 2.0?mL of waste. Slopes of analytical curves obtained for four different organic phosphorus species agreed with those obtained for orthophosphate, indicating quantitative conversion. The results for freshwater samples agreed with those obtained by the AOAC reference procedure at 95% confidence level. The organic matter did not interfere in the photo-oxidative process. The proposed procedure is a fast and environmentally friendly alternative for the phosphorus fractionation in freshwaters.     

Larvicidal potential of Juglans regia male flower against Anopheles stephensi,Aedes aegypti and Culex quinquefasciatus

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.     

Bioactivity and chemical characterisation of Lophostemon suaveolens – an endemic Australian Aboriginal traditional medicinal plant

Lophostemon suaveolens is a relatively unexplored endemic medicinal plant of Australia. Extracts of fresh leaves of L. suaveolens obtained from sequential extraction with n-hexane and dichloromethane exhibited antibacterial activity in the disc diffusion and MTT microdilution assays against Streptococcus pyogenes and methicillin sensitive and resistant strains of Staphylococcus aureus (minimum bactericidal concentration < 63 μg/mL). The dichloromethane extract and chromatographic fractions therein inhibited nitric oxide in RAW264.7 murine macrophages (IC₅₀ 3.7–11.6 μg/mL) and also PGE₂ in 3T3 murine fibroblasts (IC₅₀ 2.8–19.7 μg/mL). The crude n-hexane, dichloromethane and water extracts of the leaves and chromatographic fractions from the dichloromethane extract also showed modest antioxidant activity in the ORAC assay. GC–MS analysis of the n-hexane fraction showed the presence of the antibacterial compounds aromadendrene, spathulenol, β-caryophyllene, α-humulene and α-pinene and the anti-inflammatory compounds β-caryophyllene and spathulenol. Fractionation of the dichloromethane extract led to the isolation of eucalyptin and the known anti-inflammatory compound betulinic acid.     

Phenolic profile,antioxidant capacity and anti-inflammatory activity of Anethum graveolens L. essential oil

This study reports the chemical composition, antioxidant and anti-inflammatory properties of Anethum graveolens essential oil and its main compounds. The essential oil was obtained from the aerial parts of the plant by hydrodistillation and analysed by using GC/MS. α-Phellandrene (19.12%), limonene (26.34%), dill ether (15.23%), sabinene (11.34%), α-pinene (2%), n-tetracosane (1.54%), neophytadiene (1.43%), n-docosane (1.04), n-tricosane (1%), n-nonadecane (1%), n-eicosane (0.78%), n-heneicosane (0.67%), β-myrcene (0.23%) and α-tujene (0.21%) were found to be the major constituents of the oil. A. graveolens oil exhibit a higher activity in each antioxidant system with a special attention for β-carotene bleaching test (IC₅₀: 15.3 μg/mL) and reducing power (EC₅₀: 11.24 μg/mL). The TLC-bioautography screening and fractionation resulted in the separation of the main antioxidant compounds, which were identified as limonene (45%) and sabinene (32%). The essential oil and its main compounds exhibited a potent NO-scavenging effect and inhibited the expression of inducible NO synthase.     

Biological Applications of Synthesized ZnO Nanoparticles Using Pleurotus djamor Against Mosquito Larvicidal,Histopathology, Antibacterial,Antioxidant and Anticancer Effect

The present study pertained to biosynthesis, characterization and biomedical application (larvicidal, histopathology, antibacterial, antioxidant and anticancer activity) of Zinc oxide nanoparticles (ZnONPs) from Pleurotus djamor. The synthesized NPs were characterized using spectral and microscopic analyses and further confirmed by UV–Visible spectrophotometer with apeak of 350 nm. The ZnONPs showed strong antioxidant property (DPPH, H₂O₂ and ABTS⁺ radical assay) and expressed good larval toxicity against Ae. aegypti and Cx. quinquefasciatus (IVth instar larvae) with the least LC₅₀ and LC₉₀ values (10.1, 25.6 and 14.4, 31.7 mg/l) after 24 h treatment, respectively. We noticed the morphological changes (damaged anal papillae area and the cuticle layers) in the treated larvae. For the antibacterial assay, the highest growth inhibition zone was recorded in C. diphteriae (28.6?±?0.3 mm), followed by P. fluorescens (27?±?0.5 mm) and S. aureus (26.6?±?1.5 mm). The in vitro cytotoxicity assay depicted a significant level of cytotoxic effects (LC₅₀ values 42.26 μg/ml) of ZnONPs against the A549 lung cancer cells, even at low dose. The overall findings of the study suggest that P. djamor had the ability for the biosynthesis of ZnONPs and could act as an alternative biomedical agent for future therapeutic applications in medical avenues.

     

Chemically characterised Pimenta dioica (L.) Merr. essential oil as a novel plant based antimicrobial against fungal and aflatoxin B1 contamination of stored maize and its possible mode of action

Abstract

The chemical characterisation of Pimenta dioica essential oil (PDEO) revealed the presence of 50 components, amongst which α-Terpineol (30.31%) was the major component followed by β-Linalool (6.75%) and γ-Terpinene (4.64%). The oil completely inhibited the growth of aflatoxin B₁ secreting strain Aspergillus flavus LHP-VS-8 and aflatoxin B₁ production at 2.5?µL/mL and 1.5?µL/mL, respectively. The oil caused dose dependent reduction of methylglyoxal (an AFB₁ inducer), enhanced leakage of Ca²⁺, Mg²⁺ and K⁺ ions and significantly reduced ergosterol content of fungal plasma membrane. During in situ experiments, PDEO exhibited complete protection of fumigated maize cob slices from fungal infestation without affecting seed germination. The chemically characterised PDEO is recommended as a plant based preservative and shelf life enhancer of food commodities by preventing fungal growth, AFB₁ production and lipid peroxidation. This is the first report on PDEO as inhibitor of AFB₁ secretion and methylglyoxal biosynthesis.