Tissue damage and cytotoxic effects of Tagetes minuta essential oil against Lucilia cuprina

Bioactive components in Psidium guajava extracts elicit biotoxic attributes and distinct antioxidant enzyme modulation in the larvae of vectors of lymphatic filariasis and dengue

Control of mosquito vectors, which have caused a global disease burden, has employed various methods. However, the challenges posed by current physical and chemical methods have raised concerns about vector control programs, leading to the search for alternative methods that are less toxic, eco-friendly, and cost-effective. This study investigated the larvicidal potential of aqueous, methanol, and ethylacetate extracts of Guava (Psidium guajava) against Aedes aegypti and Culex quinquefasciatus larvae. Functional group and phytochemical characterization were performed using Fourier-Transform Infrared Spectroscopy (FTIR) and GC-MS analysis to identify the bioactive compounds in the extracts. Larval bioassays were conducted using WHO standard procedures at concentrations of 12.5, 25, 50, 125, and 250 mg/L, and mortality was recorded after 24, 48, and 72 h. Additionally, antioxidant enzyme profiles in the larvae were studied. All of the solvent extracts showed larvicidal activity, with the methanol extract exhibiting the highest mortality against Ae. aegypti and Cx. quinquefasciatus larvae, followed by aqueous and ethylacetate extracts. FTIR spectroscopic analysis revealed the presence of OH, C-H of methyl and methylene, CO and CC. The GC-MS analysis indicated that the methanol, aqueous, and ethylacetate extracts all had 27, 34, and 43 phytoactive compounds that were effective at causing larvicidal effects, respectively. Different concentrations of each extract significantly modulated the levels of superoxide dismutase, catalase, glutathione peroxidase, and reduced glutathione in larvae. This study's findings indicate the potential for developing environmentally friendly vector control products using the bioactive components of extracts from P. guajava leaves.

Phytomediated stress modulates antioxidant status, induces overexpression of CYP6M2, Hsp70, α-esterase, and suppresses the ABC transporter in Anopheles gambiae (sensu stricto) exposed to Ocimum tenuiflorum extracts

The incorporation of phytoactive compounds in the management of malarial vectors holds promise for the development of innovative and efficient alternatives. Nevertheless, the molecular and physiological responses that these bioactive substances induce remain underexplored. This present study investigated the toxicity of different concentrations of aqueous and methanol extracts of Ocimum tenuiflorum against larvae of Anopheles gambiae (sensu stricto) and unraveled the possible underlying molecular pathways responsible for the observed physiological effects. FTIR and GCMS analyses of phytoactive compounds in aqueous and methanol crude extracts of O. tenuiflorum showed the presence of OH stretching vibration, C = C stretching modes of aromatics and methylene rocking vibration; ring deformation mode with high levels of trans-β-ocimene, 3,7-dimethyl-1,3,6-octatriene in aqueous extract and 4-methoxy-benzaldehyde, 1,3,5-trimethyl-cyclohexane and o-cymene in methanol extract. The percentage mortality upon exposure to methanol and aqueous extracts of O. tenuiflorum were 21.1% and 26.1% at 24 h, 27.8% and 36.1% at 48 h and 36.1% and 45% at 72 h respectively. Using reverse transcription quantitative polymerase chain reaction (RT-qPCR), down-regulation of ABC transporter, overexpression of CYP6M2, Hsp70, and α-esterase, coupled with significantly increased levels of SOD, CAT, and GSH, were observed in An. gambiae (s.s.) exposed to aqueous and methanol extracts of O. tenuiflorum as compared to the control. Findings from this study have significant implications for our understanding of how An. gambiae (s.s.) larvae detoxify phytoactive compounds.

Acetylcholinesterase inhibition and antioxidant activity properties of Petiveria alliacea L

ETHNOPHARMACOLOGICAL RELEVANCE

Petiveria alliacea L. is traditionally used as a folk medical herb in different regions of the world to treat different ailments including those related to the central nervous system. Previous studies have proved that extracts from P. alliacea show improvement in memory and learning process.

AIM OF THE STUDY

To study extracts, fractions, subfractions and isolated compounds from P. alliacea on acetylcholinesterase inhibition and antioxidant activity.

MATERIAL AND METHODS

Extracts obtained with different polarity solvents and fractions from P. alliacea were evaluated for their inhibitory activity on acetylcholinesterase by Ellman method. This screening allowed the selection of the methanol fraction as the most active and continued a bio-guided study. The compounds identified in methanol fraction were analyzed by high performance liquid chromatography-mass spectrometry (HPLC-MS). Identification of (E)-Tagetone was performed by ¹H and ¹³C NMR spectra. Moreover, the antioxidant activity was evaluated by DPPH and ABTS methods, and the cell viability was assessed by WST-1 method.

RESULTS

Two extracts of different polarity were obtained from P. alliacea. The methanol extract and its fraction showed an inhibitory activity on acetylcholinesterase; however, methanol fraction was found to be most potent with 86.5 % AChE inhibition. The methanol fraction also showed antioxidant activity and was not toxic on SH-SY5Y cells. Different compounds including capreoside, narcissin, indane, (-)-isocaryophyllene, (-)-β-pinene, (E)-tagetone and peonidin 3-O-sambubioside 5-O-glucoside were identified.

CONCLUSION

This is the first report indicating that P. alliacea methanol fraction and its subfractions bear acetylcholinesterase inhibition and antioxidant activity properties. This work establishes the basis for further studies in the development of new therapies for neurodegenerative disorders such as Alzheimer 's disease.

Control of sheep flystrike: what's been tried in the past and where to from here

Flystrike remains a serious financial and animal welfare issue for the sheep industry in Australia despite many years of research into control methods. The present paper provides an extensive review of past research on flystrike, and highlights areas that hold promise for providing long-term control options. We describe areas where the application of modern scientific advances may provide increased impetus to some novel, as well as some previously explored, control methods. We provide recommendations for research activities: insecticide resistance management, novel delivery methods for therapeutics, improved breeding indices for flystrike-related traits, mechanism of nematode-induced scouring in mature animals. We also identify areas where advances can be made in flystrike control through the greater adoption of well-recognised existing management approaches: optimal insecticide-use patterns, increased use of flystrike-related Australian Sheep Breeding Values, and management practices to prevent scouring in young sheep. We indicate that breeding efforts should be primarily focussed on the adoption and improvement of currently available breeding tools and towards the future integration of genomic selection methods. We describe factors that will impact on the ongoing availability of insecticides for flystrike control and on the feasibility of vaccination. We also describe areas where the blowfly genome may be useful in providing impetus to some flystrike control strategies, such as area-wide approaches that seek to directly suppress or eradicate sheep blowfly populations. However, we also highlight the fact that commercial and feasibility considerations will act to temper the potential for the genome to act as the basis for providing some control options.

Human myiasis cases originating and reported in africa for the last two decades (1998-2018): A review

The article reviews literature on myiasis in Africa and cases that originated in Africa over the last two decades (1998-2018). The relevant literature was obtained by using several databases (Science-Direct, JSTOR, Google Scholar, Ebscohost and PubMed). We searched for the following words or their combination myiasis, maggots, fly species responsible for myiasis found in Africa, and the different types of myiasis. References in several articles provided links to other relevant works. Only papers written in English were reviewed. In total, we reviewed 51 articles which covered a total of 849 myiasis cases. The review encompasses geographical distribution of the disease, dipteran species responsible, predisposing factors, sex of the patient, type of myiasis and treatment. Myiasis is found in most parts of the African continent, however only 18 articles reported myiasis cases in Africa during the period under review. The rest of the articles report cases from the rest of the world but acquired by travellers when visiting Africa. Cordylobia anthropophaga (Blanchard) was responsible for 93.28% of all the reported cases in this review. The low number of articles on human myiasis reported in Africa may be due to underreporting by physicians or most cases are not diagnosed. Therefore, the actual prevalence of myiasis in Africa is currently unknown.

Effects of Tagetes minuta essencial oil on Lucilia cuprina third instar larvae

The activity of Tagetes minuta essential oil (TMEO) was tested against third instar larvae (L3) of the Australian blowfly Lucilia cuprina. We have determined the potential of the T. minuta EO as a new biopesticide candidate. To test this, groups of 20 L3 were placed on filter paper impregnated with ranging concentrations (from 0.19 to 6.36 μL/cm²) of TMEO, solubilized in acetone. Data show in this article is related to research article “Tissue damage and cytotoxic effects of Tagetes minuta essential oil against Lucilia cuprina” Chaaban et al., 2019. Thus, data of cuticle damage, color changes in L3 body and decrease in L3 motility were recorded 24 and 48 h after TMEO contact.