Transcriptome Analysis of Inflorescence Development at the Five-Leaf Stage in Castor(Ricinus communis L.)

The yield of castor is influenced by the type of inflorescence and the proportion of female flowers.However,there are few studies on the genetic mechanism involved in the development and differentiation of castor inflorescences.In this study,we performed transcriptomic analyses of three different phenotypes of inflorescences at the five-leaf stage.In comparison to the MI(complete pistil without willow leaves),290 and 89 differentially expressed genes(DEGs)were found in the SFI(complete pistil with willow leaves)and the BI(monoecious inflorescence),respectively.Among the DEGs,104 and 88 were upregulated in the SFI and BI,respectively,compared to the MI.In addition,186 DEGs and 1 DEG were downregulated in the SFI and BI compared to the MI.Moreover,we conducted GO and KEGG enrichment analyses of the DEGs.In comparison to the MI,the SFI and BI exhibited the enrichment of functional branches in DEGs,specifically in pollen wall assembly,pollen development,and cellular component assembly involved in morphogenesis.In our study,RADL5 showed low expression levels between SFI-vs.-MI types.In addition,we found that the expression of NAC in the SFI differed from that in MI and BI,and some genes related to hormonal signaling changed their expression levels during inflorescence differentiation.These results reveal the genetic mechanism of sex genotypes in castor,which will not only guide researchers in the breeding of castor but also provide a reference for genetic research on other flowering plants.

Proteomic Analyses of Three Inflorescence Styles of Castor(Ricinus communis L.)at Different Developmental Stages

Castor(Ricinus communis L.)is one of ten oil crops in the world and has complex inflorescence styles.Generally,castor has three inflorescence types:single female inflorescence(SiFF),standard female inflorescence(StFF)and bisexual inflorescence(BF).StFF is realized as a restorer line and as a maintainer line,which was applied to castor hybrid breeding.However,the developmental mechanism of the three inflorescences is not clear.Therefore,we used proteomic techniques to analyze different inflorescence styles.A total of 72 diferentially abundant protein species(DAPs)were detected.These DAPs are primarily involved in carbon and energy metabolism and carbon fixation in the photosynthetic organism pathway.The results showed that DAPs are involved in photosynthesis to control the distribution of imported carbohydrates and exported photoassimilates and thus affect the inflorescence development of castor.In addition,these DAPs are also involved in cysteine and methionine metabolism.Quantitative real-time PCR(qRT-PCR)results demonstrated that the proteomics data collected in this study were reliable.Our findings indicate that the carbon cycle and amino acid metabolism influence the inflorescence development of castor.

蓖麻(Ricinus communist L.)对锰矿区土壤中重金属累积特性的研究

为探讨蓖麻(Ricinus communist L.)对锰矿区土壤生态修复及能源化利用潜力,将不同品种蓖麻湘蓖1号和淄蓖7号播种在锰尾矿库土壤上,进入生殖生长阶段时采收全株,测定栽植土壤及植株根、茎、叶中5种重金属元素含量。结果显示:土壤中Mn平均含量最高达7 884.96 mg·kg-1,超过国家规定的土壤环境质量Ⅱ级标准6.5倍;湘蓖1号不同器官的Mn浓度从高至低为根>叶>茎,淄蓖7号不同器官Mn含量叶>茎>根,其叶中Mn平均浓度最高为765.43 mg·kg-1,较湘蓖1号叶中的平均含量高出79.53%,Pb、Cu、Cr含量及叶/根比值均大于湘蓖1号;植株体内重金属含量与土壤中重金属浓度的相关分析表明,重金属的积累量和转移量,受到土壤中几种重金属元素的共同影响。结果说明:2个品种的蓖麻均可以作为锰矿区能源化修复利用,对重金属的吸收和转运在品种间存在差异,淄蓖7号地上部分对重金属的迁移能力强于湘蓖1号。

Study on Cu Resistance of Ricinus communis L. Callus

[Objective] The article studies the growth and Cu absorption of Ricinus communis L. callus under Cu stress. [Method] CuSO4.5H20 solutions with different Cu concentrations were added to callus subculture medium; callus was inoculated and Cu resistance index of callus was worked out. Cu content in callus was deter- mined with the method of Varian AA240FS. [Result] With the Cu concentration at 60 mg/L, the growth of callus was inhibited, its Cu resistance index was only 33.87%. With the Cu concentration at 40 mg/L, callus was faint yellow in color, and grew rapidly with its Cu resistance index at 61.29%. Such high level resistance could remain the same after six week after continuous subculture. In the 4t week of culture, Cu resistance index in treatments with Cu concentrations at 10, 20, 30, 40 mg/L was higher than that in the 3rd week, and the content of Cu in callus of the treatments was 0.33, 0.54, 1.16, 1.40 mg/g respectively. [Conclusion] Cu con- centration at 40 mg/L in culture medium can be the threshold for selecting Cu re- sistance R. communis callus.

Exploration of larvicidal and adult emergence inhibition activities of Ricinus communis seed extract against three potential mosquito vectors in Kolkata,India

Objective:To determine the larvicidal and adult emergence inhibition activities of castor （Ricinus communis） seed extract against three potential mosquito vectors Anopheles stephensi（An. slephensi）,Culex quinquefasciatus（Cx.quinquefasciatus） and Aedes albopictus（Ae.albopictus） in India.Methods:The R.communis seed extract was tested,employing WHO procedure,against fourth larval instars of the three mosquito species for 24 h and larval mortalities were recorded at various concentrations（2-64μg/mL）:the 24 h LC50 values of the R.communis seed extract were determined following Probit analysis.The larval killing,antipupation and adult emergence inhibition rates of the test extract,using a single concentration of 2μLC50,were studied at different time periods（24-72 h）:the extract toxicity was tested against a fish.Oreochromis niloticus（O.niloticus）.Results:The R.communis seed extract exhibited larvicidal effects with 100%killing activities at concentrations 32-64μg/mL,and with LC50 values 7.10.11.64 and 16.84μg/mL for Cx.quinquefasciatus,An.stephensi and Ae.albopictus larvae,respectively. When the larvae were treated with the extract at a single concentration of 2×LC50,significant differences were observed,compared to control groups,in rate of pupation（P【0.001） as well as in adult formation（P【0.001）.Conclusions:The present findings suggest that the R.communis seed extract provided an excellent potential for controlling An.stephensi,Cx.quinquefasciatus and Ae. albopictus mosquito vectors.

Antimicrobial potential of Ricinus communis leaf extracts in different solvents against pathogenic bacterial and fungal strains

Objective:To investigate the in vitro antimicrobial activities of the leaf extract in different solvents viz.,methanol,ethanol and water extracts of the selected plant Ricinus communis.Methods:Ager well diffusion method and agar tube dilution method were carried out to perform the antibacterial and antifungal activity of methanol,ethanol and aqueous extracts.Results:Metbanol leaf extracts were found to be more active against Gram positive bacteria(Bacillus subtilis:ATCC 6059 and Staphylococcus aureus:ATCC 6538)as well as Gram negative bacteria(Pseudomonas aeruginosa:ATCC 7221 and Klebsiella pneumoniae)than ethanol and aqueous leaf extracts.Antifungal activity of methanol and aqueous leaf extracts were also carded out against selected fungal strains as Aspergillus fumigatus and Aspergillus flavus.Methanolic as well as aqueous leaf extracts of Ricinus communis were effective in inhibiting the fungal growth.Conclusions:The efficient antibacterial and antifungai activity of Ricinus communis from the present investigation revealed that the methanol leaf extracts of the selected plant have significant potential to inhibit the growth of pathogenic bacterial and fungal strains than ethanol and aqueous leaf extracts.

In vitro control of Staphylococcus aureus (NCTC 6571) and Escherichia coli (ATCC 25922) by Ricinus communis L.

Objective:To evaluate antibacterial activity of hot and cold ethanol and methanol leaf extracts of Ricinus communis L(R.communis)against Staphylococcus aureus(S.aureus)(NCTC 6571)and Escherichia coli(E.coli)(ATCC 25922).Methods:Leaf powder of R.communis L.was extracted with hot(in Soxhlet)and cold ethanol and methanol,separately.The antibacterial activity of the extracts was determined by agar well diffusion and macro broth dilution methods.The extracts were also subjected to phytochemical analysis.Results:All the four test extracts showed inhibition on both S.aureus and E.coli.Hot and cold ethanol extracts revealed significantly(P<0.05)higher inhibition on S.aureus than methanol extracts,and the hot ethanol extract had the lowest minimum inhibitory concentration(MIC)and minimum bactericidal concentration(MBC)values(5 mg/mL and 10 mg/mL,respectively).E.coli was highly inhibited by hot extracts of both ethanol and methanol with the MIC and MBC of 40 mg/mL and 80 mg/mL,respectively.Phytochemical analysis revealed the presence of saponins,cardiac glycosides,tannins,flavonoids and terpenoids in all test extracts.Conclusions:This study demonstrates that the hot and cold methanol and ethanol extracts are potential sources for control of S.aureus and E.coli.Especially,the hot and cold extracts of ethanol are more inhibitive against 5.aureus even at lower concentration.Further study is needed to identify the specific bioactive compounds,their mode of action and their nontoxic nature in vivo condition.

Antinociceptive activity of Ricinus communis L.leaves

Objective:To evaluate the antinociceptive activity of the methanol extract of Ricinus communis leaves(MRCL).Methods:Antinociceptive activity was evaluated using acetic acid induced writhing test,formalin induced paw licking and tail immersion method in mice at doses of 100,125 and 130 mg/kg bw.Results:The results indicated that MRCL exhibited considerable antinociceptive activity against three classical models of pain in mice.Preliminary phytochemical analysis suggested the presence of saponin,steroids and alkaloids.Conclusions:It can be concluded that MRCL possesses antinociceptive potential that may be due to saponin,steroids and alkaloids in it.

<i>Wrinkled</i>1 (WRI1) Homologs, AP2-Type Transcription Factors Involving Master Regulation of Seed Storage Oil Synthesis in Castor Bean (<i>Ricinus communis</i>L.)

Among APETALA2 (AP2)-type plant specific transcription factor family, WRINKLED1 (WRI1), has appeared to be a master gene transcriptionally regulating a set of carbon metabolism- and fatty acid synthesis (FAS)-related genes responsible for seed specific triacylglycerols (TAGs) storage in oil plants. B3 type transcription factors, such as ABI3 and FUS3, are known to be involved in seed development, such as seed storage protein synthesis and maturation. Based on the recent whole genome sequence data of castor bean (Ricinus communis L.), putative WRI1 homologs (RcWRI1, RcWRI2) specifically expressed in castor bean seed have been identified by comparing organ specific expression profiles among seed development-related transcription factors, seed storage specific genes (Ricin, RcOleosin) and a set of FAS genes including genes for sucrose synthase (RcSUS2), biotin carboxyl carrier protein (a subunit of acetyl-CoA carboxylase, RcBCCP2) and ketoacyl-acyl carrier protein synthase (RcKAS1). Immunoreactive signals with WRI1, FUS3 and ABI5-related polypeptides were also detected in seed specifically, consistent with the expression profiles of seed development-related genes. The WRI1 binding consensus sites, [CnTnG](n)(7)[CG], designated as the AW-box, were found at the promoter region of RcBCCP2 and RcKAS1. Thus, RcWRI1 possibly play a pivotal role in seed specific TAGs storage during seed development by directly activating FAS -related genes.

Effect of methanol extract of Ricinus communis seed on reproduction of male rats

Aim： To investigate the effect of methanol extract of Ricinus communis seed （RCE） on male rats reproductive functions. Methods： Thirty-two male albino rats were divided into four groups. Groups 1, 2 and 3 were gavaged with 0.2 mL of 2.5% tween 80 （RCE vehicle; control） or 20 mg/（kg-d） and 40 mg/（kg-d） of RCE, respectively, for 30 days, and group 4 was also gavaged with 40 mg/（kg.d） of RCE, but was allowed a recovery periold of 30 days. Five untreated female rats were cohabited with male rats in each group from day 25 of RCE treatment for 5 days, except group 4, where cohabitation began on day 25 of the recovery period. All male rats were sacrificed 24 h after the experiments. The female rats were laparatomized on day 19 of pregnancy and the number and weight of litters were recorded. Results： There was a significant decrease （P 〈 0.01） in the weight of the reproductive organs, sperm functions and serum levels of testosterone in RCE treated rats. There was disorganization in the cytoarchitecture of the testes, disruption of the seminiferous tubules and erosion of the germinal epithelium. The number and weight of litters of rats in groups 2 and 4 decreased significantly （P 〈 0.05） but no changes were observed in group 3. RCE caused no changes in liver, kidney, heart or body weights in male rats. Conclusion： RCE has a reversible negative impact on male reproductive functions, which appears to be mediated via gonadal disruption in testosterone secretion. （Asian J Androl 2006 Jan; 8： 115-121）

Genome-wide Identification,Classification and Expression Analysis of Lhc Supergene Family in Castor Bean(Ricinus communis L.)

Light-harvesting chlorophyll a/b-binding （LHC） proteins are a group of nuclear-encoded thylakoid proteins that play a key role in plant photosynthesis and are widely involved in light harvesting, energy transfer to the reaction center, maintenance of thylakoid membrane structure, photoprotection and response to en- vironmental conditions, etc. Although/dw supergene family is well characterized in model plants such as Arabidopsis, rice and poplar, little information is available in castor bean （Ricinus communis L. ）. In this study, a genome-wide search was carried out for the first time to identify castor bean L/w genes and analyze the gene structures, biochemical properties, evolutionary relationships and expression characteristics based on the published data of castor bean genome and ESTs. According to the results, a total of 28 Rclhcs genes representing 13 gene families （ l_hca , l_hcb , Elip , Ohpl , Ohp2 , SEP1, SEP2 , SEP3 , SEP4 , SEP5 , PsbS , Rieske and FCII） and 25 subgene families were identified in castor bean genome; to be specific, 25 and 5 genes were found to have corresponding ESTs in NCBI and have al- ternative splicing isoforlns, respectively. These RcLhcs contain 0 to 9 introns and distribute on 26 of the 25 878 released scaffolds. All RcLhcs genes were found to be expressed in all examined tissues, i.e. leaf, flower, II/III stage endosperm, V/VI stage endosperm and seed, with the highest expression level in leaf tissue.

In vitro establishment of a highly effective method of castor bean (Ricinus communis L.) regeneration using shoot explants

An efficient plant regeneration protocol was established for castor bean （Ricinus communis L.）, in which 0.3 mg L-1 thidiazuron （TDZ） induced shoot clusters and increased the number of adventitious shoots from hypocotyl tissue. Our results showed that treatment under dark conditions significantly promoted the average number of shoots per explant to 37.36±4.54 （with a 6-d treatment）. Modified 1/2 Murashige and Skoog （MS） basal medium supplemented with 440 mg L-1 Ca2＋, 0.2 mg L-1 gibberellic acid and 0.1 mg L-1 TDZ significantly increased shoot elongation rates and lowered vitrification rates. Further- more, 1/2 MS media supplemented with 0.2 mg L-11-naphthaleneacetic acid induced a higher rooting rate compared with other culture conditions.

In vitro antimicrobial and larvicidal properties of wild Ricinus communis L. in Mauritius

Objective: To explore the phytochemical and antimicrobial activities as well as the insecticidal properties of the different sections of Ricinus communis(castor) plant in Mauritius.Methods: Qualitative and quantitative methods were used for the determination of phytochemicals in the crude leaves, pericarp, seeds, bark and root extracts obtained by using polar and non-polar solvents. The disc diffusion and micro-dilution methods were used to evaluate the antimicrobial activities of the crude solvent extracts against 13 microorganisms. The insecticidal properties of the crude extracts on larvae of Bactrocera zonata(Diptera: Tephritidae), which caused important economic losses to local fruits were also investigated.Results: All the extracts from the different parts of the plant showed antimicrobial activity against most tested microorganisms. The polar solvents' extracts of the fully mature parts of the castor plant were active against the Pseudomonas aeruginosa(ATCC 27853),Escherichia coli(E. coli)(ATCC 25922), E. coli(0145:H28 Acc. No. CP006027.1) with inhibition zones ranging from 16 mm to 19 mm and against Bacillus cereus(ATCC11778)(B. cereus), Listeria innocua(ATCC 33090)(L. innocua). Lowest microbial inhibitory concentration was recorded for B. cereus, L. innocua, Staphylococcus aureus(ATCC 29213), E. coli(ATCC 25922) and Proteus mirabilis strain(NCTC 11938) with value of 3.2 mg/m L. The most active extract against both Gram-negative and Grampositive bacteria was extracted from the fully mature pericarps and it was the most active against E. coli(ATCC 25922), B. cereus, L. innocua and Staphylococcus aureus(ATCC 29213). In addition, the extracts obtained by using polar solvent and fully mature leaves demonstrated the strongest larvicidal activity against Bactrocera zonata(100%).Conclusions: Ricinus communis(castor) plant extracts possess larvicidal properties providing an effective eco-friendly control for fruit flies. The antimicrobial results justify the use of this plant in traditional medicine and the practice of supplementing decoctions/concoctions with conventional antibiotics.

Therapeutic role of Ricinus communis L. and its bioactive compounds in disease prevention and treatment

Ricinus communis L.(R. communis), commonly known as castor oil plant, is used as a traditional natural remedy or folkloric herb for the control and treatment of a wide range of diseases around the globe. Various studies have revealed the presence of diverse phytochemicals such as alkaloids.flavonoids, terpenes, saponins,phenolic compounds such as kaempferol, gallic acid, ricin, rutin, lupeol, ricinoleic acid, pinene, thujone and gentisic acid.These phytochemicals have been responsible for pharmacological and therapeutic effects,including anticancer, antimicrobial, insecticidal, antioxidant, anti-diabetic, antinociceptive,anti-inflammatory. bone regenerative, analgesic, and anticonvulsant activity. R. communis harbours phytochemicals which have been shown to target peroxisome proliferator activated receptor(PPAR), nuclear factor NF-κ-B, cytochrome p450, P38 mitogen-activated protein kinases kinase(p38 MAPK), tumor protein P53, B-cell lymphoma-extra-large(Bcl-xL) and vascular endothelial growth factor receptor-2(VEGFR-2). Considering its wide variety of phytochemicals, its pharmacological activity and the subsequent clinical trials, R. communis could be a good candidate for discovering novel complementary drugs. Further experimental and advanced clinical studies are required to explore the pharmaceutical, beneficial therapeutic and safety prospects of R. communis with its phytochemicals as a herbal and complementary medicine for combating various diseases and disorders.

Removal of Malachite Green Dye from Aqueous Solutions onto Microwave Assisted Zinc Chloride Chemical Activated Epicarp of <i>Ricinus communis</i>

Competitive adsorption of malachite green (MG) in single and binary system on microwave activated epicarp of Ricinus communis (MRC) and microwave assisted zinc chloride activated epicarp of Ricinus communis (ZRC) were analyzed. The preparation of ZRC from Ricinus communis was investigated in this paper. Orthogonal array experimental design method was used to optimize the preparation of ZRC. Optimized parameters were radiation power of 100 W, radiation time of 4 min, concentration of zinc chloride of 30% by volume and impregnation time of 16 h, respectively. The MRC and ZRC were characterized by pHzpc, SEM-EDAX and FTIR analysis. The effect of the presence of one dye solution on the adsorption of the other dye solution was investigated in terms of equilibrium isotherm and adsorption yield. Experimental results indicated that the uptake capacities of one dye were reduced by the presence of the other dye. The adsorption equilibrium data fits the Langmuir model well and follows pseudo second-order kinetics for the bio-sorption process. Among MRC and ZRC, ZRC shows most adsorption ability than MRC in single and binary system.

DNA Barcoding of <i>Ricinus communis</i>from Different Geographical Origin by Using Chloroplast <i>matK</i>and Internal Transcribed Spacers

Ricinus communis have attracted considerable attention because of its specific industrial and pharmacological activities. DNA barcodes can be used as reliable tools to facilitate the identification of medicinal plants for the safe use, quality control and forensic investigation. In this study, the differential identification of eight accessions of R. com-munis was investigated through DNA sequence analysis of two candidate DNA barcodes. The nucleotide sequence of internal transcribed spacers (ITS2) and chloroplast maturase gene (matK) have been determined to construct the phylogenetic tree. The phylogenetic relationships of accessions based on the nrITS2 region and partial matK region showed that all accessions in this study were related to three geographical origins. Based on sequence align-ment and phylogenetic analyses we concluded that the ITS2 sequences can distinguish R. communis accessions from different geographical distributions.

Studies on Cell Suspension Culture of Ricinus communis L.

Ricinus communis L. is a new copper hyperaccumulator growing on Tonglushan copper mine in Hubei Province, China. This study aimed to establish a suspension cell line of R. communis L. with stable and rapid growth for further screening of heavy metal-resistant R. communis L. cells and breeding of hyperaccu- mulators. In this study, cell suspension culture conditions were optimized by using orthogonal experimental design with previously induced R. communis L. embyre- genic calluses as experimental materials, to establish the suspension cell line of R. communis L. Under the optimal conditions, growth curves of suspension cells and changes in pH of culture liquid were determined. The results showed that the optimal culture conditions for R. conmmnis L. suspension cell line were ： MS ＋ O. 5 rag/I, 6-BA ＋ O. 2 mg/L NAA ＋ 50 mg/L sucrose ＋ 350 mg/L casein hydrolysate as basic medium, with callus inoculation amount of 2.5 g/50 ml, dark culture at （26 ±2） ℃ with shaking at 110 r/min. Under these conditions, increment of fresh weight and dry weight ofR. commun/s L. suspension cells reached the maximum of 4.56 g/（50 ml 14 d） and 0.49 g/（50 ml 16 d）, respectively. Growth curves of R. communis L. suspension cells were basically in ＂S＂ shape. Each culture cycle lasted 16 d, and the rapid growth stage was from the 6th d to the 14th d. In a culture cycle, pH of the culture liquid declined first and then increased to the maximum and stabilized gradually.

Phytoremediation of Pb Spiked Soils Amended with Iron ImpregnatedRice Husk Ash Using Ricinus communis L. (Castor bean)

Heavy metals pose a serious risk to the environment and living biota. Potstudies were carried out to determine the competence of Fe-coated ricehusk in Pb spiked soils vegetated with Ricinus communis. Physicochemicalproperties of Fe- coated rice husk ash (Fe-RHA) were characterizedon dry weight basis. Pot experiments were carried out with seedlings ofR.communis for 60 days amended with Fe-RHA (0, 2.5% and 5% w/w)and Pb(NO3) [0, 400 and 800 mg kg?1]. Addition of Fe-coated rice huskash to Pb cntaminated soils improved soil pH and fertility. Treatment with5% Fe-RHA decreased Pb accumulation in roots by 84%. Addition of Fe-RHA significantly (p<0.05) increased plant physiological parameters suchas height, leaf diameter, nodes, and leaf number by 64%, 49%, 62% and66% and chlorophyll contents (12–29%) compared to unamended plants.Our findings conclude that Fe-RHA is a low-cost, environmentally friendlyand efficient adsorbent for stabilization of Pb spiked soils.

Rigid foam polyurethane （PU） derived from castor oil （Ricinus communis） for thermal insulation in roof systems

This paper discusses the response of the thermal insulation Lining of rigid foam potyurethane （PU） derived from castor oil （Ricinus communis） in heat conditions, based on dynamic climate approach. Liners have been widely used, because the coverage of buildings is responsible for the greatest absorption of heat by radiation, but the use of PU foam deMved from this vegetal oil is unprecedented and has the advantage of being biodegradable and renewable. The hot wire paraLleL method provided the thermal conductivity vatue of the foam. The thermo- gravimetric analysis enabled the study of the foam decomposition and its Lifetime by kinetic evaLuation that involves the decomposition process. The PU foam thermal behavior analysis was performed by coLlecting experimental data of internal surface temperature measured by thermocouples and assessed by representative episode of the climatic fact. The results Lead to the conclusion that the PU foamderived from castor oit can be applied to thermat insulation of roof systems and is an environmentaLLy friendly materiaL.

Phytochemical, Anti-oxidant, Larvicidal, and Antimicrobial Activities of Castor(Ricinus communis) Synthesized Silver Nanoparticles

Objective Castor possesses the medicinal properties. Hence, castor extract has the reducing power agent was used in nanoparticles synthesis. Extract of castor also produces secondary metabolites （phenolics, reducing agent） and exhibits anti-oxidant property, which was used as larvicide and antimicrobial agent. In the present study the silver nanoparticles （AgNPs） were synthesized using aqueous leaf extract of castor. Methods The synthesized AgNPs were characterized with UV-visible spectroscopy and transmission electron microscopy （TEM）. The phenolics, reducing sugar and total sugar were evaluated performing Folin-Ciocalteu reagent method, DNS method and Phenol-sulphuric acid method. Anti-oxidant activity of synthesized nanoparticles was evaluated using DPPH assay. The larvicidal activity of synthesized AgNPs was evaluated against the third instar of Anopheles stephensi and Aedes aegypti. The mortality was observed after 24 h by probit analysis. Further, the antimicrobial activity was reported against Staphylococcus aureus （Gram positive） and Pseudomonas aeruginosa （Gram negative）. Results The UV spectra showed maximum absorbance at 445 nm and TEM analysis indicated spherical shape of nanoparticles with average size of 8.96 nm. The synthesized nanoparticles also possessed anti-oxidant potentials. Thus, it could be used as potential free radical scavenger. The larvae of A. stephensiwere found more susceptible to AgNPs than larvae of A. aegyptL Conclusion Due to the medicinal properties and reducing power activity, in the present study AgNPs have been synthesized using the aqueous leaves extract of castor and access their phytochemical, anti-oxidant, larvicidal and antimicrobial properties.