Biological activity of Xanthium strumarium seed extracts on different cancer cell lines and Aedes caspius,Culex pipiens (Diptera: Culicidae)

Effects of methanol extracts of Xanthium strumarium on different cancer cell lines and on the mortality rates of Aedes caspius, Culex pipiens (Diptera: Culicidae) were investigated. Among the cell lines tested, the Jurkat cell line was the most sensitive to the methanol extract and ethyl acetate fraction, with reported LC₅₀ values of 50.18 and 48.73 μg/ml respectively. Conversely, methanol extracts were not that toxic to the A549 cell line though the toxicity increased on further purification. The percentage of growth inhibition was dose dependent for the methanol extract and ethyl acetate fraction. The ethyl acetate fraction showed higher toxicity to all cell lines tested when compared to the methanol extract. The results showed that methanol extracts of plant seeds caused 100% mortality of mosquito larvae at a concentration of 1000 μg/ml after 24 h of treatment. The LC₅₀ and LC₉₀ values of X. strumarium were found to be 531.07 and 905.95 μg/ml against Ae. caspius and 502.32 and 867.63 μg/ml against Cx. Pipiens, respectively. From the investigations, it was concluded that the crude extract of X. strumarium showed a weak potential for controlling the larval instars of Ae. caspius and Cx. pipiens. However, on further purification the extract lost the larvicidal activity. The ethyl acetate fraction showed higher toxicity to all cell lines tested when compared to the methanol extract. The ethyl acetate fraction investigated in this study appears to have a weak larvicidal activity but a promising cytotoxic activity. Future studies will include purification and investigation in further detail of the action of X. strumarium on Cancer Cell Lines and mosquitoes.     

The effect of Achyranthes japonica extract on larval survival and development and oviposition behavior of Plutella xylostella L. (Lepidoptera: Plutellidae)

The extract of Achyranthes japonica was tested for effects on larval survival and development and the oviposition behavior of the diamondback moth, Plutella xylostella L. Chinese cabbage dipped in A. japonica extract solution showed 51–80% antifeedant activity for 5 days against P. xylostella larvae, and more larvae were also on untreated cabbage leaves 24 h after release. The mortality of P. xylostella larvae increased proportionally to the duration of dipping time in the extract, and both pupation and emergence rates of larvae feeding only on treated cabbage were lower than those for larvae raised on untreated or with a choice of cabbage. The 20-hydroxyecdysone (20E) concentration in leaves was approximately 549, 1232, 1275, and 1426 μg/g at 6, 12, 24, and 48 h after dipping treatment, respectively. Notably, naive females laid more eggs on untreated cabbage than on treated cabbage, and females from larvae raised on treated Chinese cabbage also preferred the non-treated leaves. Our results are in contrast to those from earlier studies using various insect models that confirmed most females prefer to lay eggs on the host type that was eaten in the larval stage (Hopkins host selection principle). Cabbage dipped in the A. japonica solution for 24 h caused 59% larval mortality and inhibited both pupation and emergence rates of the larvae when exposed to plants 15 and 22 days after planting in the field, with the 20E concentration in the treated cabbage leaves at 1600.9 ± 122.36 and 1386.8 ± 24.69 μg/g, respectively. Therefore, the biological effectiveness could be attributed to the 20E in the treated cabbage leaves.     

Larvicidal activity of some fungal extracts on Aedes caspius and Culex pipiens (Diptera: Culicidae)

A preliminary study was conducted to evaluate the effects of nine methanol fungal extracts on fourth instar larvae of Aedes caspius and Culex pipiens (Diptera: Culicidae). None of the extracts tested showed larvicidal activity except for the Paecilomyces lilacinus extract, which showed 100 % mortality against the larvae of Ae caspius after 24 h. The LC₅₀ values of the P. lilacinus extract after 24 h were 190.66 μg/mL against Ae. caspius and 254.25 μg/mL against Cx. pipiens, respectively. After 48 h, meanwhile, the LC₅₀ values were 65.70 and 164.13 μg/mL, respectively. Histological analysis of the midgut of the treated larvae of Ae. caspius and Cx. pipiens revealed changes such as cell destruction, spacing between the cells and disruption of the microvilli, resulting in an appearance of vacuolization in the midgut. This article is the first report of the use of P. lilacinus extract for the control of Ae. caspius and Cx. pipiens larvae and the data obtained may help to provide a better understanding of the mode of action of P. lilacinus as an insecticide against mosquito larvae.     

Insecticidal effects of a novel polyherbal formulation (HF7) against Culex pipiens L. (Diptera: Culicidae)

Plant secondary metabolites represent the most efficient and convenient method to control and overcome environmental pollution and insecticidal resistance. This study explored the mosquitocidal activity of the combined extract of seven plants, (HF7) extracted using a Soxhlet extractor against Culex pipiens under laboratory conditions. Exposure of the 3rd instars of Cx. pipiens to HF7 hexane extract resulted in LC₅₀:114.5 μg/mL and LC₉₀:117.0 μg/mL values after 24 h. The ovicidal activities of hexane extract against Cx. pipiens eggs were 21.6%, 48.3%, and 71.6% at 187.5, 93.7, and 46.88 μg/mL, respectively. HF7-treated larvae showed the formation of irregular blebbing of epithelial cells toward the lumen and sloughing into the gut lumen. HF7 extract resulted in 100% adulticidal mortality at the concentration of 3.7 mg/test tube after 30 min of exposure. The IC₅₀ of HF7 extract was 97.03 µg/ml against larvae, at which nuclear and morphological changes were observed. The spectroscopy spectrum of HF7 hexane extract disclosed the presence of 57 different secondary metabolites, among which the dominant compound was eugenol (32.3%). HF7 hexane extract could serve as a botanical insecticide for controlling Cx. pipiens and potentially other mosquito species.     

Effect of entomopathogens on Africanized Apis mellifera L. (Hymenoptera: Apidae)

This study aimed to evaluate the effect of commercially used entomopathogens on Africanized Apis mellifera L. (Hymenoptera: Apidae). Four bioassays were performed: 1) pulverized entomopathogens on A. mellifera; 2) entomopathogens sprayed on a smooth surface; 3) entomopathogens sprayed on soy leaves; and 4) entomopathogens mixed with candy paste (sugar syrup). Five treatments were prepared: sterile distilled water (control), distilled water sterilized with Tween^® 80 (0.01%), and the commercial entomopathogens Metarhizium anisopliae E9 (1.0 × 10⁹ conidia mL^?1), Beauveria bassiana PL63 (1.0 × 10⁸ conidia mL^?1) and Bacillus thuringiensis var. kurstaki HD-1 (3.0 × 10⁸ spores mL^?1). Each treatment consisted of five repetitions, with 20 workers per repetition, which were stored in a plastic box and, later, in a biological oxygen demand (B.O.D.) incubator (27 ± 2 °C, RH of 60% ± 10%, 12-h photophase). The mortality of the workers was evaluated from 1 h to 240 h, and the data were analyzed using Bayesian inference. The workers killed by the ingestion of candy paste contaminated with the pathogens (products) were randomly separated and selected for the removal of the midgut. Each midgut was fixed in Bouin's solution and prepared for histology. B. bassiana was verified to reduce the survival of A. mellifera workers in all bioassays. Moreover, M. anisopliae reduced the survival of A. mellifera workers directly sprayed, on a smooth surface and mixed with candy. B. thuringiensis reduced A. mellifera survival on a smooth surface and mixed with candy paste. However, its effects were lower than that observed by B. bassiana. The treatments with the biological products did not induce morphometric alterations in the midgut of A. mellifera.     

New antiprotozoal agents: Synthesis and biological evaluation of different 4-(7-chloroquinolin-4-yl) piperazin-1-yl)pyrrolidin-2-yl)methanone derivatives

In an endeavor to develop efficacious antiprotozoal agents 4-(7-chloroquinolin-4-yl) piperazin-1-yl)pyrrolidin-2-yl)methanone derivatives (5–14) were synthesized, characterized and biologically evaluated for antiprotozoal activity. The compounds were screened in vitro against the HM1: IMSS strain of Entamoeba histolytica and NF54 chloroquine-sensitive strain of Plasmodium falciparum. Among the synthesized compounds six exhibited promising antiamoebic activity with IC₅₀ values (0.14–1.26 μM) lower than the standard drug metronidazole (IC₅₀ 1.80 μM). All nine compounds exhibited antimalarial activity (IC₅₀ range: 1.42–19.62 μM), while maintaining a favorable safety profile to host red blood cells. All the compounds were less effective as an antimalarial and more toxic (IC₅₀ range: 14.67–81.24 μM) than quinine (IC₅₀: 275.6 ± 16.46 μM) against the human kidney epithelial cells. None of the compounds exhibited any inhibitory effect on the viability of Anopheles arabiensis mosquito larvae.     

Larvicidal activities of the stem bark extract and rotenoids of Millettia usaramensis subspecies usaramensis on Aedes aegypti L. (Diptera: Culicidae)

The dichloromethane/methanol (1:1) extract of the stem bark of Millettia usaramensis subspecies usaramensis was tested for its larvicidal activity against the 4th instar Aedes aegypti larvae and demonstrated activity with LC₅₀ value of 50.8 ± 0.06 μg/mL at 48 h. Compounds isolated from the extract were also tested for their larvicidal activities, and the rotenoid usararotenoid-A (LC₅₀ 4.3 ± 0.8 μg/mL at 48 h) was identified as the most active principle. This compound appears to be the first rotenoid having a trans-B/C ring junction and methylenedioxy group at C-2/C-3 with high larvicidal activity. Related rotenoids with the same configuration at the B/C-ring junction did not show significant activity at 100 μg/mL.     

Target and non-target effects of Foeniculum vulgare and Matricaria chamomilla combined extract on Culex pipiens mosquitoes

The present study focused on extracting green larvicides from extracts of the combination of Foeniculum vulgare and Matricaria chamomilla using different solvents of increasing polarity in a Soxhlet extractor and evaluating their ovicidal, larvicidal, and cytotoxic activities. The most promising among all tested extracts was hexane extract. The ovicidal activity of the hexane PH2 extract resulted in a significant (p < 0.05) decrease in egg hatchability from 95.00 ± 6.16% to 15 ± 9.04% at doses ranging from 62.5 to 500 µg/mL. The larval mortality with the hexane extract ranged from 13.33 ± 3.3% to 93.33 ± 3.3% at doses ranging from 31.25 to 250 µg/mL, respectively. The LC₅₀ and LC₉₀ values of the larvicidal activity of the hexane extract were estimated to be 148.3 and 242.17 µg/mL, respectively, after 24 h of exposure. Similarly, the LC₅₀ values after 48 and 72 h of exposure were 124.93 and 100.3 µg/mL, respectively, against the third instar of Cx. pipiens. PH2 treatment of larvae resulted in histopathological changes such as degenerated epithelial cells and destruction of microvilli on the epithelial cells. The PH2 extract achieved a dose-dependent decrease in the rate of cell survival. The IC₅₀ value of PH2-treated HUVECs was 192.07 µg/mL after 24 h of incubation. The cells showed changes in cellular and nuclear morphology. In conclusion, the hexane extract of PH2 could be used in mosquito management programs.     

Insecticidal and developmental inhibitory properties of monoterpenes on Culex pipiens L. (Diptera: Culicidae)

Twelve monoterpenes were evaluated for larvicidal and adulticidal activities towards Culex pipiens. Geraniol and cuminaldehyde were the most toxic monoterpenes to larvae, with LC₅₀ values of 38.6 and 38.9 mg/l after 24 h of treatment, respectively, whereas cuminaldehyde was the most potent compound after 48 h of treatment, followed by geraniol and thymol. In fumigant toxicity experiments, (R)-carvone and geraniol were the most toxic monoterpenes against the adults at all three tested concentrations and after both 24 and 48 h. When tested at sublethal concentrations (0.5 LC₅₀), (R)-carvone, (S)-limonene and cuminaldehyde decreased hatchability, pupation and adult emergence and induced high larval mortality. Our results suggest that geraniol, cuminaldehyde and (R)-carvone are promising toxicants against Culex pipiens and could be useful in the search for new natural insecticides.     

Biological activities of plant extracts from Ficus elastica and Selaginella vogelli: An antimalarial,antitrypanosomal and cytotoxity evaluation

The cytotoxic, antiplasmodial, and antitrypanosomal activities of two medicinal plants traditionally used in Cameroon were evaluated. Wood of Ficus elastica Roxb. ex Hornem. aerial roots (Moraceae) and Selaginella vogelii Spring (Selaginellaceae) leaves were collected from two different sites in Cameroon. In vitro cell-growth inhibition activities were assessed on methanol extract of plant materials against Plasmodium falciparum strain 3D7 and Trypanosoma brucei brucei, as well as against HeLa human cervical carcinoma cells. Criteria for activity were an IC₅₀ value < 10 μg/mL. The extract of S. vogelii did not significantly reduce the viability of P. falciparum at a concentration of 25 μg/mL but dramatically affected the trypanosome growth with an IC₅₀ of 2.4 μg/mL. In contrast, at the same concentration, the extract of F. elastica exhibited plasmodiacidal activity (IC₅₀ value of 9.5 μg/mL) and trypanocidal (IC₅₀ value of 0.9 μg/mL) activity. Both extracts presented low cytotoxic effects on HeLa cancer cell line. These results indicate that the selected medicinal plants could be further investigated for identifying compounds that may be responsible for the observed activities and that may represent new leads in parasitical drug discovery.     

Antileishmanial evaluation of clubbed bis(indolyl)-pyridine derivatives: One-pot synthesis,in vitro biological evaluations and in silico ADME prediction

A new series of bis(indolyl)-pyridine derivatives 6(a–m) were synthesized by Chichibabin reaction process and evaluated for antileishmanial and antibacterial activities to establish structure–activity relationship. The synthesis was carried out through one-pot multicomponent reaction of 3-acetylindole, aromatic aldehydes, and ammonium acetate in the presence of camphor-10-sulfonic acid as a catalyst. The compounds 6d (IC₅₀ = 102.47 μM) and 6f (IC₅₀ = 99.49 μM) had shown promising antileishmanial against L. donovani promastigotes when compared with standard sodium stibogluconate (IC₅₀ = 490.00 μM). All the synthesized compounds (MIC range = 41.35–228.69 μg/mL) had shown potent antibacterial activity than standard ampicillin (MIC range = 100.00–250.00 μg/mL) against all the tested bacterial strains. In silico ADME and metabolic site prediction studies were also held out to set an effective lead candidate for the future antileishmanial and antibacterial drug discovery initiatives.     

Temperature and dose effects on the pathogenicity and reproduction of two Korean isolates of Heterorhabditis bacteriophora (Nematoda: Heterorhabditidae)

Out of some isolated Heterorhabditis bacteriophora from Korea, ecological study on two isolates which had different geographical features was investigated. That is, effects of temperature and dose on the pathogenicity and reproduction of two Korean isolates of H. bacteriophora were investigated using Galleria mellonella larvae in the laboratory. The median lethal dose (LD₅₀) decreased with increasing temperature, but increased at 35 °C. The optimal temperatures for infection were 30 °C for H. bacteriophora Jeju strain and 24 °C for H. bacteriophora Hamyang strain. The median lethal time, LT₅₀ of H. bacteriophora Hamyang strain was recorded at 13 °C to 35 °C and that of H. bacteriophora Jeju strain was recorded at 18 °C to 30 °C. The number of established nematodes in G. mellonella larvae was significantly different depending on temperature and dose. When G. mellonella larvae were exposed to 300 infective juveniles (IJs), mortality of G. mellonella gradually increased with exposure time with H. bacteriophora Jeju strain but not with H. bacteriophora Hamyang strain. 87.5% mortality of G. mellonella was recorded by H. bacteriophora Hamyang strain after 1440 min whereas 100% mortality was recorded by H. bacteriophora Jeju strain after 4320 min. The time from infection to the first emergence of nematodes decreased with increasing temperature. Duration of emergence of the two strains in the White traps also decreased with increasing temperature. The highest progeny numbers of H. bacteriophora Jeju strain were 264,602 while those of H. bacteriophora Hamyang strain were 275,744 at the rate of 160 IJs at 24 °C.     

Potential for integrated control of Culex quinquefasciatus (Diptera: Culicidae) using larvicides and guppies

Acute toxicity tests were carried out to determine the effect of three larvicides, spinosad, pirimiphos methyl, and chlorpyrifos, on Culex quinquefasciatus Say, Anopheles gambiae s.s. Giles (Diptera: Culicidae), and guppies, Poecilia reticulata Peters (Pisces: Poeciliidae). Thereafter, larvae of Cx. quinquefasciatus were introduced to P. reticulata in containers of different volumes with low concentrations of each larvicide at established predator to prey densities of 1–35; 5–70 and 10–350 (fish to larvae) respectively. The experiment was replicated six times, and the larval consumption was counted after 24 h. Spinosad and pirimiphos methyl were significantly toxic to Cx. quinquefasciatus, the less susceptible mosquito species. Guppy consumption of Culex larvae was highest at a predator to prey density 5–70. Feeding activity of guppies increased in the spinosad treatment at 49 μg L⁻¹ compared to control and the synthetic larvicides. The synthetic larvicides generally reduced consumption of larvae except for the lowest concentration of pirimiphos methyl which increased it at the highest predator to prey density in a 3 L container. The highest percentage of Culex larvae was consumed by fish in the presence of spinosad at 49 μg L⁻¹ and a predator to prey density of 5–70 in 0.5 L plastic containers. Thus, predator to prey density, container size, type and concentration of larvicide are all important factors to be considered in integrated management of mosquito larvae.     

Chrysanthemum extract and extract prepared silver nanoparticles as biocides to control Aedes aegypti (L.), the vector of dengue fever

Mosquitoes play a key role in the transmission of some important diseases. The need for controlling these insects is critical to reduce their risks to human and domesticated animals. Recently the trend to explore effective chemical compounds from local plants has begun as a safe means of control. The present study aimed to evaluate the anti-larval activity of Chrysanthemum extract and the prepared silver nanoparticle (AgNPs) against the Aedes aegypti mosquito, the dengue vector in Saudi Arabia. A series of different concentrations of ethanol extract and extract prepared AgNPs against the fourth-life larvae was tested. The effective concentrations of crude extract and AgNPs ranged from 50 to 250 and 10 to 30 ppm respectively, and the death percentages corresponding to these concentrations ranged from 18 to 92 and 36 to 96% respectively. According to the LC₅₀ values of treated larvae, AgNPs (12.754 ppm) is more effective against A. aegypti mosquito larvae than the crude extract (228.345 ppm) at about 17.9 times. The mixing of the plant extract with the silver nitrate has led to potentiation. This is due to the synergy that occurs between the extract and the silver particles during the reduction process. The compounds in the extract are related to the surface of the particles, increasing the strength of their effects. It is recommend to separate the active elements in the Chrysanthemum plant and its preparation in the form of nanoparticles as a promising compound in mosquito control programs with least damage to human kind and the environment.     

C-2 (E)-4-(Styryl)aniline substituted diphenylpyrimidine derivatives (Sty-DPPYs) as specific kinase inhibitors targeting clinical resistance related EGFRT790M mutant

With the aim to overcome the drug resistance induced by the EGFR T790M mutation (EGFR^T790M), herein, a family of diphenylpyrimidine derivatives (Sty-DPPYs) bearing a C-2 (E)-4-(styryl)aniline functionality were designed and synthesized as potential EGFR^T790M inhibitors. Among them, the compound 10e displayed strong potency against the EGFR^T790M enzyme, with the IC₅₀ of 11.0 nM. Compound 10e also showed a higher SI value (SI = 49.0) than rociletinib (SI = 21.4), indicating its less side effect. In addition, compound 10e could effectively inhibit the proliferation of H1975 cells harboring the EGFR^T790M mutation, within the concentration of 2.91 μM. Significantly, compound 10e has low toxicity against the normal HBE cell (IC₅₀ = 22.48 μM). This work provided new insights into the discovery of potent and selective inhibitor against EGFR^T790M over wild-type (EGFR^WT).     

Larvicidal activity and Histopathological changes of Cinnamomum burmannii,Syzygium aromaticum extracts and their combination on Culex pipiens

In order to develop an eco-friendly botanical larvicide alternative to the synthetic larvicides, extracts were prepared from the Cinnamomum burmannii (C.B.) and Syzygium aromaticum (S.A.) with hexane using a sonicator. The extracts were evaluated for larvicidal activity individually and in combination against the Culex pipiens larvae. The LC₅₀ value of C.B. and the S.A. hexane extracts tested individually were 184.2 and 363.7 µg/mL against Cx. pipiens respectively. All the combinations of the extract of C.B. and S.A. showed synergistic factors higher than one. Among the different ratios of extracts, the SA25%: CB75% extract was found to be more toxic than the other combinations (LC₅₀:125.7 µg/mL). Midgut cells treated with S.A. 25%: C.B. 75% extract showed severe morphological alterations such as degradation of microvilli; degeneration of epithelial cells, and peritrophic membrane; loss of nuclei, irregular and damage of microvilli. The extract has a promising larvicidal potential against Cx. pipiens, However, the extract was toxic against HUVEC cells, as evident from MTT and cell morphology. Further investigation is required to assess the toxicity of the extract on aquatic animals.     

Ovarian development and histological observations of threatened dwarf snakehead fish,Channa gachua (Hamilton, 1822)

Channa gachua were monthly sampled throughout a year and the histological analysis of their ovaries was done to determine the changes occurring in ovarian development. Based on histological examination of the ovaries, the oogenic process of C. gachua undergoes distinct cyclic and seasonal morphological changes. Five different developmental stages were identified under three major categories: pre-spawning (immature, maturing, mature), spawning (ripe-running) and post-spawning (spent). The peak spawning period of C. gachua was noticed during December - February. The gonadosomatic index (GSI) and ova diameter ranged from 0.79 to 3.61% and 543–1123 μm respectively. The highest mean GSI (3.61 ± 0.16) and oocyte diameter (1123 ± 55 μm) were observed in December indicating that during this month the gonadal development reached maturity.     

Killing kinetics of anidulafungin,caspofungin and micafungin against Candida parapsilosis species complex: Evaluation of the fungicidal activity

Background

Candida parapsilosis, Candida metapsilosis and Candida orthopsilosis are emerging as relevant causes of candidemia. Moreover, they show differences in their antifungal susceptibility and virulence. The echinocandins are different in terms of in vitro antifungal activity against Candida. Time-kill (TK) curves represent an excellent approach to evaluate the fungicidal activity of antifungal drugs.

Antioxidant,anticancer, apoptosis properties and chemical composition of black truffle Terfezia claveryi

Desert truffles are seasonal and important edible fungi that grow wild in many countries around the world. Truffles are natural food sources that have significant compositions. In this work, the antioxidant, chemical composition, anticancer, and antiangiogenesis properties of the Terfezia claveryi truffle were investigated. Solvent extractions of the T. claveryi were evaluated for antioxidant activities using (DPPH, FRAP and ABTS methods). The extracts cytotoxicity on the cancer cell lines (HT29, MCF-7, PC3 and U-87 MG) was determined by MTT assay, while the anti-angiogenic efficacy was tested using ex-vivo assay. All extracts showed moderate anticancer activities against all cancer cells (p < 0.05). The hexane extract inhibited the brain cell line (U-87 MG) with an IC₅₀ of 50 μg/ml and significantly promoted cell apoptosis through the mitochondrial pathway and DNA fragmentation p < 0.001. The ethanol extract demonstrated potent antioxidants; DPPH, FRAP, and ABTS with an IC₅₀ value of 52, 48.5 and 64.7 μg/ml, respectively. In addition, the hexane and ethyl acetate extract significantly (p < 0.001) inhibited the sprouting of microvessels by 100% and 81.2%, at 100 μg/ml, respectively. The GC analysis of the most active extract (hexane) showed the presence of several potent phytochemicals such as stigmasterol, beta-Sitosterol, squalene, lupeol, octadecadienoic acid, and oleic acid.