Jatropha Curcas Research Articles

A comprehensive physicochemical characterization and proposed portfolios of applications for the fruits and seeds of 11 accessions of Jatropha curcas L.

The seed oil and extraction cake from 11 accessions of Jatropha curcas from Mexico, El Salvador, and India were comprehensively characterized with the objective of selecting parentals based on desirable traits for a hybridization program. Kernels contained up to 65 % oil and up to 30 % protein. The most abundant protein types were glutelins (48 %) and globulins (24 %), with arginine (0.096 mg/g) and leucine (0.070 mg/g) being the major amino acids. Glucose (0.09 g/g) and arabinose (0.03 g/g) were the most abundant carbohydrates. The oil was primarily composed of oleic (41 %) and linoleic (37 %) acids. The physicochemical properties of the oil included an acid value of 0.28–1.15 %, saponification value of 155–208 mg KOH/g, iodine value of 0.97–1.08 g I2/g, and viscosity of 21.9–40.9 cSt at 40 °C. Six accessions were selected as parental candidates based on their potential as feedstock for a diverse portfolio of products. The most common applicability of oils were lubricants, biopolymers, biofertilizer, and liquid biofuels production. One Mexican accession had a phorbol-ester concentration much lower than the toxicity threshold (0.06 mg/g) and a high protein content, making it attractive for the animal feed industry and for protein extraction. The selected accessions are preserved in a local germplasm bank and will be used for continued genetic improvement through hybridization, aiming to preserve the identified traits while increasing fruit productivity.

A comprehensive techno-eco-environmental investigation of an efficient biodiesel generation procedure through hydrodynamic cavitation

The growth of cleaner biodiesel generation associated with hydrodynamic cavitation from canola oil via transesterification is acquiring prominence owing to considerably descending energy needs and time. In this work, the conversion of canola oil into biodiesel and glycerol was achieved through the process of transesterification with methanol, employing sodium hydroxide as a catalyst. The newly offered process was investigated from technical, economic, and environmental points of view, and the precision of the results was verified and accepted compared to previously published works. The technical results revealed that the maximum exergy destruction rates as well as exergy efficiency belonged to the transesterification process. The economic study showed that the capital cost of the process was 638.7 MUSD/year. Also, the return period was computed less than 4 years. Moreover, comparison analysis proved that Canola oil proved to be a more advantageous primary material for the production of biodiesel and was more appropriate from the exergoeconomic point of view in comparison to Jatropha oil and other materials. Finally, by increasing the conversion percentage of the reactor, the value of the exergo-environmental index and the factor of exergy stability increased significantly, which was considered as an advantage from an environmental standpoint.

Modeling the Effects of Temperature in Enzymatic Biodiesel Synthesis of Jatropha Oil: An Optimal Control Approach.

Biodiesel, an alternative to diesel, is produced through the enzymatic transesterification of vegetable oil or animal fats. Enzymatic transesterification of oil is gaining more importance, as this method possesses no such disadvantages that are associated with the chemical process. Temperature is the most important factor in enzymatic transesterification for biodiesel synthesis. In this study, a mathematical model is developed to understand the effects of temperature on the enzymatic transesterification of Jatropha curcas oil. Reaction rates are expressed as a function of temperature using an appropriate function, and the effects of temperature on the overall enzymatic system are investigated using the mathematical model. A suitable temperature is determined using the mathematical model, keeping the other reaction conditions unchanged that gives maximum yield. Furthermore, an optimal control problem (OCP) is formulated to identify the temperature control strategy that maximizes the biodiesel yield while minimizing production costs. Simulated outcomes obtained from the mathematical model are analogized with the experimental results to make them acceptable. The optimal profile of temperature is determined from the developed OCP, which maximizes the biodiesel yield.

Determining the Phytochemical Properties and Antibiogram of Different Chewing Stick Plants on Selected Streptococcal Species Isolated from the Oral Cavity

Chewing sticks are small twigs obtained from plant stems, measuring 12-25cm long and tied in bundles of 5-10. These twigs have been used for oral hygiene for many years, even before the invention of toothpaste, mouthwash, and mouth sprays. This study aims to determine the phytochemical properties and antibiogram of different chewing stick plants on two streptococcal species isolated from the oral cavity. Streptococcus pyogenes and Streptococcus mutans were isolated from oral swabs of patients at Rivers State University Teaching Hospital and identified to the species level. The pure isolates were further tested against the antimicrobial effects of the aqueous and ethanolic extracts of four chewing stick plants: Vernonia amygdalina, Jatropha curcas, Massularia acuminate, and Phyllanthus mullerianus. Qualitative phytochemical screening and quantitative analysis were carried out on the plant stems to determine the presence of antimicrobials. The percentage of antimicrobials present in the plant stems ranged from 33.3% to 66.7%, with Jatropha curcas, Massularia acuminate, and Vernonia amygdalina exhibiting the highest percentages, and Phyllanthus mullerianus the lowest. The antibiogram of the isolates to conventional gram-positive antibiotics was determined by the disc diffusion method. Streptococcus pyogenes showed 75% sensitivity and 25% resistance to the antibiotics, while Streptococcus mutans displayed 50% sensitivity, 16.7% intermediate, and 33.3% resistance to the antibiotics. The investigation found that the ethanolic extract of Massularia acuminate has the highest zone of inhibition of 15.5 ±0.71mm at 100mg/ml, while Phyllanthus mullerianus exhibited the least inhibition at 8 ±0mm. The ethanolic extract of Jatropha curcas and Vernonia amygdalina showed little effect on the test isolates, with a range of 0-9.5±0.71mm. The aqueous extract ranged from 8±5.7 - 9.5±0.71mm at 100mg/ml, with Massulara acuminate exhibiting the highest and the lowest zones of inhibition. This finding indicates that Massularia accuminate has the ability to suppress the growth of dental plaque-forming Streptococcus mutans and Streptococcus pyogenes. Chewing sticks are more affordable and easily accessible, so they could be recommended in community oral health programs.

Comparative analysis of the combustion and emission characteristics of biojet and conventional Jet A‐1 fuel: a review

AbstractConventional jet fuels derived from fossil sources contribute to greenhouse gas emissions and air pollution, leading to climate change. Recent studies have shown that biobased jet fuels from different feedstocks offer a more sustainable alternative to conventional fuels as they are derived from renewable biomass, reducing greenhouse gas emissions. The major feedstocks reviewed are jatropha curcas, camelina, karanja oil, waste cooking oil, and municipal solid waste. They offer diverse benefits for sustainable aviation fuel development. As a comparative analysis, this review examined jet fuel characteristics based on their physicochemical properties, namely energy content, viscosity, calorific value, cetane number, and freezing and flash points. The objective was to understand the influence of the properties on performance evaluation, environmental impact, and combustion characteristics. The properties of biojet fuels are compared with their fossil counterparts to validate their suitability as renewable alternatives and their benefits in terms of emissions reduction and engine performance. Biojet fuels perform better in terms of lower sulfur content, lower soot content, and a lower freezing point, their aromatic content, and their high cetane number. This study enhances the understanding of biojet fuels and their quality, and supports the development of sustainable fuel options. Overall, adherence to the American Society for Testing and Materials (ASTM) D7566‐18 standard is crucial for the acceptance and integration of biojet fuels into the aviation sector. Future research should explore feedstocks such as wood biomass, wastepaper, and agricultural residues for biojet fuels. It should also investigate the combustion and emission characteristics of biosourced aviation fuel at higher blending ratios (>50% by volume) with fossil Jet A‐1.

Euphorbiaceae superoxide dismutase, catalase, and glutathione peroxidase as clues to better comprehend high drought tolerance in castor bean

Superoxide dismutase (SOD), Catalase (CAT), and Glutathione peroxidase (GPX) enzymes exert a central role in reactive oxygen species (ROS) scavenger in plants, being an important part of enzymatic antioxidant system. Despite the importance of these enzymes in ROS metabolism and in different signaling pathways related to plant development and stress response, their gene families have not yet been comprehensively characterized in many crop plants. Among different crops, the Euphorbiaceae family has some species highly tolerant to drought stress. However, the gene families that encode the antioxidant enzymes, as well as their role in this drought stress tolerance, remains not characterized. Here, the SOD, CAT, and GPX genes of castor bean (Ricinus communis), cassava (Manihot esculenta), jatropha (Jatropha curcas), rubber tree (Hevea brasiliensis), petty spurge (Euphorbia peplus), and annual mercury (Mercurialis annua) were identified and characterized. The comprehensive phylogenetic and genomic analyses allowed the classification of the genes into different classes and revealed the duplication events that contribute to the expansion of these families within plant genomes. The expression patterns of SOD, CAT, and GPX genes were examined in castor bean, cassava, jatropha, and rubber tree by RNA-seq analysis revealing differential expression during stress. Additionally, the castor bean gene expression was confirmed by RT-qPCR. Among castor bean genes, RcGPX4 appears to be induced in castor bean roots under drought stress, but the heterologous expression in Arabidopsis thaliana does not improve the drought tolerance. Altogether, this data has significantly contributed to characterizing the expression patterns and conducting evolutionary assessment of these genes in Euphorbiaceae. This bridge a gap in understanding the proposed functions of core components within the antioxidant mechanism in an economically significant group of plants, particularly during stress responses

RSM integrated GWO, Driving Training, and Election-Based Algorithms for optimising ethylic biodiesel from ternary oil of neem, animal fat, and jatropha

The worldwide exploration of the ethanolysis protocol (EP) has decreased despite the multifaceted benefits of ethanol, such as lower toxicity, higher oxygen content, higher renewability, and fewer emission tail compared to methanol, and the enhanced fuel properties with improved engine characteristics of multiple-oily feedstocks (MOFs) compared to single-oily feedstocks. The study first proposed a strategy for the optimisation of ethylic biodiesel synthesis from MOFs: neem, animal fat, and jatropha oil (NFJO) on a batch reactor. The project's goals were to ensure environmental benignity and encourage the use of totally biobased products. This was made possible by the introduction of novel population based algorithms such as Driving Training-Based Optimization (DTBO) and Election-Based Optimization (EBOA), which were compared with the widely used Grey Wolf Optimizer (GWO) combined with Response Surface Methodology (RSM). The yield of NFJO ethyl ester (NFJOEE) was predicted using the RSM technique, and the ideal transesterification conditions were determined using the DTBO, EBOA, and GWO algorithms. Reaction time showed a strong linear relationship with ethylic biodiesel yield, while ethanol-to-NFJO molar ratio, catalyst dosage, and reaction temperature showed nonlinear effects. Reaction time was the most significant contributor to NFJOEE yield.The important fundamental characteristics of the fuel categories were investigated using the ASTM test procedures. The maximum NFJOEE yield (86.3%) was obtained at an ethanol/NFJO molar ratio of 5.99, KOH content of 0.915 wt.%, ethylic duration of 67.43 min, and reaction temperature of 61.55 °C. EBOA outperforms DTBO and GWO regarding iteration and computation time, converging towards a global fitness value equal to 7 for 4 s, 20 for 5 s and 985 for 34 s. The key fuel properties conformed to the standards outlined by ASTMD6751 and EN 14,214 specifications. The NFJOEE fuel processing cost is 0.9328 USD, and is comparatively lesser than that of conventional diesel. The new postulated population based algorithm models can be a prospective approach for enhancing biodiesel production from numerous MOFs and ensuring a balanced ecosystem and fulfilling enviromental benignity when adopted.

Enhancing diesel engine performance and emissions control with reduced Graphene oxide and Non-Edible biodiesel blends

The growing concern about environmental degradation and the depletion of fossil fuel supplies has prompted experts to investigate alternate and sustainable transportation energy sources. In these circumstances, biodiesel made from renewable feedstock has emerged as a viable environmentally friendly alternative to conventional diesel. This study thoroughly examines the performance and emission characteristics of a 4-stroke diesel engine running on biodiesel blends, including reduced graphene oxide (rGO) nanomaterial. The non-edible biodiesel from the Jatropha curcas plant is utilized, and it is blended in various ratios with conventional diesel, ethanol, and nanomaterial rGO to improve performance and emissions parameters. Torque increased by up to 17 % in rGO DJE02GO25 at 3500 rpm, while Brake Power decreased by 6.3 % in rGO DJE01GO25 at 2600 rpm. Brake Thermal Efficiency decreased by 12.5 % in rGO Blend 1 at 2600 rpm, and Brake-specific fuel consumption decreased by 16.5 % in rGO DJE02GO25 at 3500 rpm. CO2 emissions decreased up to 19.71 % in rGO Blend 10 at 2600 rpm. HC emissions decreased to 94 % in rGO blend 8 at 3500 rpm. Finally, NOx emissions decreased up to 84.78 % in rGO Blend 1 at 2900 rpm. The current study reveals that after adding rGO nanomaterial in biodiesel, there is a significant decrease in NOx and HC emissions.

Assessing the effect of different biodiesels on corrosion of nickel alloy

This investigation explores the corrosion behaviour of Ni alloy (UNS718), which is a potential material for storing biodiesel and making engine components. The study also examines the connection between Ni alloy corrosion and biodiesel degradation. Immersion tests were conducted using in-house biodiesels to evaluate the corrosion rates of Used Cooking Oil (UCOB), Karanja oil (KOB), and Jatropha oil (JOB) biodiesels on Ni alloy (UNS718). The results highlighted the role of corrosion product morphology and the formation of corrosion-driven pitting, cracks, etc., on Ni alloy when exposed to different biodiesels such as KOB, JOB, and UCOB. The study utilized gravimetric techniques to measure the corrosion rate and advanced analytical tools such as FESEM, EDS, XPS, NMR and XRF. It revealed decreased corrosion rates of Ni alloys with prolonged biodiesel immersion. For example, after 2160 h, Jatropha biodiesel exhibited a corrosion rate of 0.000699 mm/year, while the corrosion rates of Ni alloy exposed to UCOB and KOB were 0.001398 mm/year and 0.001048 mm/year, respectively. The study also suggests a detailed mechanism of Ni alloy corrosion when exposed to different biodiesels such as Karanja, Jatropha, and Used Cooking Oil.

Genetic Diversity and Population Genetic Structure of Jatropha curcas L. Accessions from Different Provenances Revealed by Amplified Fragment-Length Polymorphism and Inter-Simple Sequence Repeat Markers

The genetic diversity and structure of 17 populations of J. curcas, including 92 accessions from different provenances (tropical and subtropical), were investigated and effectively evaluated using twelve inter-simple sequence repeats (ISSRs) and seven pairs of florescence-amplified fragment-length polymorphism (AFLP) primers. Genetic diversity, at the overall level among populations of J. curcas based on the ISSR markers, showed that the observed number of alleles (Na) was 1.593, the effective number of alleles (Ne) was 1.330, Nei’s gene diversity (H) was 0.200, Shannon’s information index (I) was 0.303, and the percentage of polymorphic loci was 59.29%, indicating moderate genetic diversity between and within the different populations of J. curcas. Based on the genetic diversity analysis of AFLP markers, there were 1.464 (Na) and 1.216 (Ne) alleles, Nei’s gene diversity (H) was 0.132, Shannon’s information index (I) was 0.204, and the percentage of polymorphic loci was 46.40%. The AMOVA analysis showed that this large variance was due to differences within the populations, with genetic distinctions and limited gene flow among those from varied regions. The 17 populations were clustered into five main groups via UPGMA clustering analysis based on Nei’s genetic distance, and the genetic relationships among the populations exhibited no significant correlations with geographical provenances. The genetic variation among Chinese populations of J. curcas distributed in dry-hot valley areas was remarkable, and the American germplasm presented with distinct genetic differentiation.

Optimizing Jatropha curcas bioenergy plantations in Pakistan: A geospatial suitability analysis using advanced spatial modeling

Bioenergy from energy plants, an alternative fuel, is projected to increasingly meet future worldwide energy demands as well as those of a developing nation like Pakistan. Jatropha curcas (JC) has been found to possess many desirable qualities, including high oil content seeds (27–40 %), rapid growth, ease of growing, tolerance to drought, ability to grow on poor soil and wasteland, needing less nutrient input and management, and not interfering with current food crops, insects, or pest resistance. Hence, growing JC in highly appropriate barren lands could reduce the global reliance on fossil fuels. However, an evaluation of the suitability of the land would be required for tree establishment to be effective. In this study, we integrated an Analytical Hierarchy Process (AHP) with the ArcGIS tool for assessing suitable available sites to cultivate JC across Pakistan. Using geospatial technologies, this study intended to assess and map possible areas appropriate for JC bioenergy plantations with the necessary climate, soil type, and topography factors. Pakistan was classified into 3 levels of suitability for JC plantations based on the results of a spatial analysis that integrated various data sets and varied evaluation criteria: Most Suitable, Moderately Suitable, and Less Suitable. Our results showed that out of the total area of Pakistan, around 54,392,075 hectares (57 %), 22,516,700 hectares (23 %), and 19,594,100 hectares (20 %) were identified as highly suitable, moderately suitable, and less suitable, respectively, for JC bioenergy plantations. We conclude that the methods used in this study provided a considerably reliable estimate of suitable sites for JC production in Pakistan. It can assist smallholder-based initiatives to promote JC cultivation on farmer-owned to enhance their living circumstances. Multi-criteria decision analysis (MCDA) was found to be a beneficial tool in breaking down the issues of identifying and classification of the locations for afforestation in the management of forests.

Optimization of Biodiesel Production from Jatropha Oil and its Impact on Engine Performance and Emissions Using Response Surface Methodology

This study aims to improve biodiesel production by assessing the effects of biodiesel-diesel fuel blends on engine performance and emissions using response surface methodology (RSM). The biodiesel was produced by the transesterification process. Here we see how the molar ratio (A), catalyst quantity (B), reaction temperature (C), and reaction time (D) affect the biodiesel conversion rate. During optimization, a Box-Behnken design (BBD) based on RSM was employed. Ideal conditions for achieving a biodiesel yield of 98.2069% were a B of 0.811601 wt%, a C of 75.8837°C, a D of 98.2069 min, and A of 10935:1. Adjusting parameters like engine speed and biodiesel fuel mix ratio enhanced engine behavior and condensed exhaust emissions. The trials were structured utilizing the central composite design (CCD) technique grounded on RSM. The optimum operating criteria for the engine were evaluated to be a biodiesel ratio of 12.5845% and speed of engine is 2011.24 rpm. Under these conditions, the power output was 50.0817kW, torque was 254.757 Nm, smoke opacity was 6.48966%, CO emissions were 270.009 ppm, and NOx emissions were 819.573 ppm.

Interactions and mechanisms of phenolic compounds with human immunodeficiency virus-1 Tat protein

Human immunodeficiency virus remains a serious health threat, with an increase of 24% newly cases globally. Targeting Tat protein is an emerging therapeutic strategy for inhibiting the feedback loop that drives the exponential increase in viral transcription and particle production of the virus. The study aimed to determine the inhibitory potential of phenolic compounds from Ricinus communis L. and Jatropha curcas L., against the Tat C protein using in silico techniques. Phenolic compounds identified from both plants were screened by absorption-distribution-metabolism-excretion (ADME) analysis using drug-likeness prediction. Molecular docking analysis of the compounds with drug-like properties against the receptor and ligand-protein complexes’ analysis and visualization were performed. The results revealed three phenolic compounds with the highest negative binding affinity to the receptor’s active site: ellagic and neochlorogenic acids with - 7.2 kcal/mol and isohemiphloin with -7.3 kcal/mol. The interacting amino acids of the complexes were majorly His13, Lys19, Lys28, Thr64, His65, Gln66, Pro70, Gln72, and Pro73 via non-covalent interactions: hydrogen bonds, hydrophobic, and electrostatic interactions. The identified phenolic compounds provide a core structure that can be candidate for plant-based antiviral drugs development to potentially aiding in the virus’s therapeutic challenge.

Ethyl Acetate Extract of Jatropha curcas L. leaves as an Inhibitor of Histamine-Forming Bacterium in Fish Scombroid

Ethyl Acetate Extract of Jatropha curcas L. leaves as an Inhibitor of Histamine-Forming Bacterium in Fish Scombroid

Jatropha Oil Biodiesel: Production Process, Fuel Characterization and Engine Efficiency Evaluation

Jatropha Oil Biodiesel: Production Process, Fuel Characterization and Engine Efficiency Evaluation

Hydro-co-processing Jatropha oil and crude oil blend with Ni-Mo-supported Al2O3 catalyst to produce hybrid fuels: the effect of catalyst particle size

Hydro-co-processing Jatropha oil and crude oil blend with Ni-Mo-supported Al2O3 catalyst to produce hybrid fuels: the effect of catalyst particle size

Sub-acute dermal toxicity of Jatropha curcas Linn. leaf extract coated silver nanoparticles (SNPs) in wistar rats

The application of different nanoparticles is underway in the development of phyto-medicines. Silver nanoparticles (AgNPs) are commonly used as coating agents to treat various bacterial and viral diseases. Their safety and potential toxicity necessitate further research to explore the development of nanoparticles coated herbal drugs. The Azadirachta indica (neem) 5% leaf extract and silver nitrate was used to prepare the silver nanoparticles (SNPs) with the biological reduction (green synthesis) method [1]. The application of silver nanoparticles (SNPs) coated with J. carcus leaf extract (JcLE) on Wistar rats showed no adverse sign of toxicity on hematological parameters except an increase in the neutrophil count and increased in total erythrocyte count (TEC) on 28th day. Similarly, serum biochemical values exhibited an increase in aspartate aminotransferase (AST/SGOT) and alanine transaminase (ALT/SGPT) with JcLE-coated SNPs in treated groups. The histopathology revealed that there was no alteration in skin architecture, however, minimal alteration was observed in the liver and kidney with dilatation of the central vein and sinusoidal space, fatty change in the liver, multifocal necrobiotic changes, cystic degeneration and mild focal glomerular atrophy and hyaline cast in the lumen of tubules of kidney. It indicates the proper absorption and excretion of SNPs from the body. There was no significant effect on hematological parameters in the rats treated with J. curcas leaf extract-coated SNP. However, the serum biochemical analysis revealed a toxic effect on the kidney.

Antitumor activity of protein fraction of Jatropha curcas In DMBA and UV B induced skin tumors in mice: Expression of Bcl-2

Antitumor activity of protein fraction of Jatropha curcas In DMBA and UV B induced skin tumors in mice: Expression of Bcl-2

First Report of Colletotrichum queenslandicum Causing Leaf Anthracnose on Jatropha curcas L in China.

Jatropha curcas L. (Euphorbiaceae), is a valuable multi-purpose crop, previously used for disease treatment and environmental restoration, recently is attention to use jatropha oil for produce biodiese. In June 2023, the leaf disease of approximately 60% of J. curcas was observed in Mazhang, Zhanjiang, Guangdong Province (E110°27'26.8'' N22°6'14.7''). Diseased leaves showed typical anthracnose symptoms of chlorotic regions with brownish sunken necrotic lesions (Figure 1). Sections from the junction of disease were surface disinfected in 75% ethanol and 3% hydrogen peroxide solution for 1 minute each. Four small pieces of infected tissue were removed from the lesion and placed on potato dextrose agar (PDA), and incubated at 25 to 28℃ in the dark. Hyphal tips from the inoculated tissues were subcultured on PDA and two isolates were purified by single spore method. The colonies on PDA were 7.8 cm diam after 10 d at 25 to 28 ℃, covered with dense, cottony, grayish-white aerial mycelium and small dark-based acervuli with orange ooze and dark brown straight setae. Conidia were hyaline, smooth-walled, aseptate, the apex and base rounded, slightly constricted near centre, 12.9 - 13.8 × 3.9 - 4.6 um (av.13.6 × 4.3 μm, n = 50). Appressoria were variable in shape, mostly simple, subglobose or irregular lobes, 5.8-9.6 × 5.7-11.2 um (Figure 2). Perithecia were not observed. These characteristics were consistent with Colletotrichum sp. (Weir, B. S., et al. 2012). Sequences of isolates ACCC 35630 and ACCC 35631 stored in Agricultural Culture Collection of China including internal transcribed spacer (ITS), actin (ACT), beta-tubulin (tub2), glyceraldehyde-3-phosphate dehydrogenase (GAPDH) and chitin synthase (chs). were amplified (Weir et al, 2012), sequenced and submitted to GenBank (ITS: PP474979 and PP474984; ACT: PP505487 and PP505488; TUB: PP505493 and PP505494; GAPDH: PP505491 and PP505492; CHS: PP505489 and PP505490). The amplicon sizes of ITS, ACT, TUB, GAPDH, and CHS were 550, 652, 500, 264, and 301 bp, respectively. Phylogenetic analyses showed that Isolates 35630 & 35631 were clustered closely association with RHCOL1 and RHCOL3. Phylogenetic analysis with MEGA 7 using the combined ITS-ACT-CHS-GAPDH-TUB2 sequences showed that the two isolates clustered with C. queenslandicum (Figure 3). To test the pathogenicity, ten healthy leaves on plants in the field were wiped with 75% alcohol and sterile water, punctured with a sterile needle and inoculated by adding 10 uL of spore suspension (1 × 105 conidia/ml) to the wounded sites. And two other leaves were added sterile water as controls. Symptoms of anthracnose were observed on leaves similar to the disease described above after 7 days of inoculation, whereas the leaves from the controls remained asymptomatic. C. queenslandicum was reisolated from the inoculated leaves. C. queenslandicum has been reported as a pathogen causing leaf and fruit anthracnose on papaya, coffee, rambutan, avocado and Persian lime etc. in tropical and temperate regions (Kunta, M., et al. 2018), and this is the first report on J. curcas in China as well as worldwide. This disease may have a significant negative impact on J. curcas cultivation.

Larvicidal and Synergistic Properties of Fixed Oils Derived from Plants and their Capacity to inhibit Pupation and Emergence of Malaria Vector (Anopheles gambiae)

Malaria vectors have evolved resistance to almost all WHO-recommended insecticides, which compromises vector control. This study aimed to evaluate the insecticidal activity of four doses of fixed oils from Jatropha curcas and Ricinus communis on Anopheles gambiae in western Burkina Faso. Biological tests of susceptibility to oil doses were carried out on two populations of the An. gambiae complex from August to October 2022 using the WHO standard protocol. The synergistic or antagonistic effects of the extracts’ combinations were evaluated by comparing “sums of effects” to “effects of sums” according to the WHO protocol. R software enabled probit and ANOVA analyses. All oils showed larvicidal activity on susceptible strains of An. gambiae, Kisumu. The LC50 of the combination of the two oils was lower (54.09±1.03 ppm), followed by the oil of J. curcas (58.8±1.03 ppm) and that of R. communis (139.0±1.04 ppm) on the field strain of An. gambiae. J. curcas oil was more toxic on both strains, leading to 100% mortality at 48h and 72h of exposure. Synergistic insecticidal effects after 24h and additive effects after 48h of the combined oil at 50 and 150 ppm resulted in 41.75% to 91.66% mortality of larvae and reduced pupation from 2.66% to 0.00% and reduced the emergence of An. gambiae from 1.16 to 0.00%. J. curcas and R. communis’ oils contain linalool, tannins, alkaloids, saponins, and terpenes. Applying J. curcas or R. communis oil or a combined oil at 50 and 150 ppm as a spray could constitute an effective strategy for integrated control of An. gambiae mosquitoes.