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1.
Comput Struct Biotechnol J ; 23: 3132-3142, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-39229336

RESUMO

Trypsin inhibitors are known to act against insect pests by inhibiting proteases of the digestive tract. In this study, we report structural and functional characterization of ∼ 19 kDa Albizia procera Kunitz-type trypsin inhibitor (ApKTI) protein with potential bio-insecticidal applications. Crystal structure of ApKTI protein has been refined to 1.42 Å and molecular structure (8HNR) showed highly beta sheeted conformation including 12 beta sheets, 15 loops and two small alpha helices. Docking between predicted model of Tribolium castaneum trypsin (TcPT) and 8HNR produced a stable complex (-11.3 kcal/mol) which reflects the inhibitory potential of ApKTI against insect gut trypsin. Significant mortality was observed in all life stages of T. castaneum including egg, larvae, pupae and adults with a 3.0 mg native ApKTI treatment in comparison to negative control. Although standard trypsin inhibitor (Glycine max trypsin inhibitors; GmKTI; 3.0 mg) produced maximum reduction against all above life stages; however, a non-significant mortality difference was observed in comparison to 3.0 mg native ApKTI. The study further explores the synthesis and characterization of Graphene (GNPs) and Zinc oxide (ZnONPs) nanoparticles, followed by the optimization of ApKTI and GmKTI loading on both nanoparticles to evaluate their enhanced insecticidal effectiveness. Encapsulated proteins showed significant mortality against T. castaneum across all concentrations, with GNPs proving more effective than ZnONPs. Additionally, encapsulated GmKTI produced significant mortality of eggs compared to loaded ApKTI treatments while other life stages were non-significantly affected by two proteins. This research highlights the importance of encapsulated ApKTI protein for eco-friendly pest management strategies.

2.
BMJ Open ; 14(5): e078203, 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38772885

RESUMO

OBJECTIVE: The prevalence of postnatal anxiety is high among women during the first year of childbirth globally. Rates are higher in low and middle-income countries (LMICs), that is, 24%. Existing literature on maternal mood and its impact on child development has largely focused on postnatal depression. Postnatal anxiety has been recognised to have significant independent effects similar to those of postnatal depression, including negative effects on various aspects of maternal well-being including quality of life, parent-child interaction and child development. The evidence exploring lived experiences of postnatal anxiety is limited from LMICs. This study explored the lived experiences of anxiety in postnatal mothers in Pakistan. DESIGN: A phenomenological approach was used for this qualitative study. The audio-recorded interviews were transcribed and analysed using the process of thematic analysis. SETTINGS: The study was conducted in two community settings in Karachi, Pakistan; the Bin Qasim and Gadap town. PARTICIPANTS: Women who were 18 years of age or older, had a live childbirth within the previous 12 months and had a score of 10 or higher on the Generalised Anxiety Disorder-7. RESULTS: In-depth, one-to-one interviews were conducted with 10 participants. The qualitative data comprised of three themes. Theme one: Factors perceived to be associated with postnatal anxiety, Theme two: The perceived impact of postnatal anxiety and Theme three: Support needs. The first theme was further subdivided into two subthemes, that is, Mothers' perception of navigating domestic responsibilities and sociocultural norms of motherhood and financial constraints. CONCLUSION: Despite the high prevalence of postnatal anxiety in LMICs there is not any published evidence on exploring this phenomenon through in-depth research in Pakistan. Understanding the lived experiences will help health professionals to identify women at risk of developing postnatal anxiety and to develop effective culturally appropriate interventions for women with anxiety during this postnatal period.


Assuntos
Ansiedade , Mães , Pesquisa Qualitativa , Humanos , Feminino , Paquistão/epidemiologia , Adulto , Mães/psicologia , Ansiedade/psicologia , Ansiedade/epidemiologia , Adulto Jovem , Qualidade de Vida/psicologia , Entrevistas como Assunto , Período Pós-Parto/psicologia
3.
Children (Basel) ; 10(6)2023 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-37371145

RESUMO

As a lifelong condition, intellectual disability (ID) remains a public health priority. Parents caring for children with ID experience serious challenges to their wellbeing, including depression, anxiety, stress and health-related quality of life. Integrated parenting interventions, which have been well evidenced for depressed mothers, may also effectively support depressed parents with a child with ID in low-resource settings such as Pakistan, and in turn optimise child outcomes. We conducted a mixed-method rater-blind feasibility randomised controlled trial, which assessed the feasibility and acceptability of the Learning Through Play in My Own Way Plus (LTP-IMOW Plus) intervention. Mothers who screened positive for depression (n = 26) with a young child (age 3-6 years) with ID were recruited from two low-resource community settings. Participants in the intervention arm (n = 13) received 12 group sessions of LTP-IMOW Plus and others (n = 13) received routine care. The intervention was feasible and acceptable with 100% retention and 100% session attendance. The intervention improved depression, anxiety, parenting stress and child socialisation score outcomes relative to the routine care arm. The framework utilised to analyse the qualitative interviews with seven participants at pre-intervention identified a range of struggles experienced by the mothers, and at post-intervention, found improved knowledge of child development and practices, improved mother-child relationships, recommendations for the intervention and perceived practical barriers and facilitators. The findings highlight the prospects for a clinical and cost-effective trial of an integrated parenting intervention to manage long-term parental mental health needs and improve child outcomes.

4.
Toxicol Rep ; 9: 1172-1179, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36518385

RESUMO

Tribolium castaneum (Herbst), one of the invasive stored pest, is resistant to the most of synthetic insecticides used against this it. Moreover, synthetic insecticides are a major threat to human health, the environment, and the ecosystem. The development of some smart tools is needed to minimize the use of hazardous chemicals. As an alternative, nano-insecticides are on the horizon. Emulsions are expressed as sustain release of insecticidal components to achieve maximum efficacy and low residual toxicity. In this study, some essential oils (Cymbopogon citratus (DC.) Stapf, Ocimum basilicum L., Curcuma longa L., and Trachyspermum ammi L.), diatomaceous earth (DE), and their nano-emulsions are evaluated against T. castaneum. Essential oils and DE were tested at four (60 ppm, 30 ppm, 15 ppm, 7.5 ppm) different concentrations with and without emulsions, and data was recorded after 6, 12, 24, 48, and 72 h of exposure respectively. The mortality observed in essential oils of C. citratus, O. basilicum, and C. longa without emulsion after 72 h of treatment at the highest concentration was 98%, 95%, and 85%, respectively. While, at the highest concentration the lowest mortalities were observed with DE and T. ammi i.e. 65%. Insecticidal activity of emulsion essential oils increased to 100%, 98%, 90%, and 68.3% for C. longa, C. citratus, O. basilicum, and T. ammi, respectively. The results support that these admixed emulsions could be used as an alternative to synthetic insecticides in conventional formulations.

5.
Insects ; 13(12)2022 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-36555079

RESUMO

For environment-friendly, safe and nonpersistent chemical control of a significant polyphagous insect pest, Helicoverpa armigera, discovery of growth-regulating xenobiotics can offer a sustainable alternative to conventional insecticides. For this purpose, chemically synthesized compounds to inhibit sterol carrier protein (SCP-2) function using in silico and in vivo assays were evaluated to estimate their impact on the survivals and lifetable indices of H. armigera. From nine chemically synthesized compounds, OA-02, OA-06 and OA-09 were selected for this study based on binding poses mimicking cholesterol, a natural substrate of sterol carrier protein and molecular dynamics simulations. In vivo bioassays revealed that all compounds significantly reduced the larval and pupal weight accumulations and stadia lengths. Subsequently, the pupal periods were prolonged upon treatment with higher doses of the selected compounds. Moreover, OA-09 significantly reduced pupation and adult emergence rates as well as the fertility of female moths; however, fecundity remained unaffected, in general. The life table parameters of H. armigera were significantly reduced when treated with OA-09 at higher doses. The population treated with 450 µM of OA-09 had the least net reproductive rates (Ro) and gross reproductive rate (GRR) compared to the control population. The same compound resulted in a declining survival during the early stages of development coupled with reduced larval and pupal durations, and fertility. These results have a significant implication for developing an effective and sustainable chemical treatment against H. armigera infestation.

6.
Dose Response ; 20(2): 15593258221108280, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35734395

RESUMO

Vicilins are major seed storage proteins and show differential binding affinities toward sugar moieties of fungal cell wall and insect gut epithelium. Hence, purpose of study is the thorough in-silico characterization of interactions between vicilin and chitin oligomer followed by fungal and insecticidal bioassays. This work covers the molecular simulation studies explaining the interactions between Pisum sativum vicilin (PsV) and chitin oligomer followed by protein bioassay against different pathogens. LC-MS/MS of purified PsV (∼50 kDa) generated residual data along high pea vicilin homology (UniProtKB ID; P13918). Predicted model (PsV) indicated the characteristic homotrimer joined through head-to-tail association and each monomer is containing a bicupin domain. PsV site map analysis showed a new site (Site 4) into which molecular docking confirmed the strong binding of chitin oligomer (GlcNAc)4. Molecular dynamics simulation data (50 ns) indicated that chitin-binding site was comprised of 8 residues (DKEDRNEN). However, aspartate and glutamate significantly contributed in the stability of ligand binding. Computational findings were further verified via significant growth inhibition of Aspergillus flavus, A. niger, and Fusarium oxysporum against PsV. Additionally, the substantial adult population of Brevicoryne brassicae was reduced and different life stages of Tribolium castaneum also showed significant mortality.

7.
Curr Med Chem ; 29(42): 6446-6462, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35676855

RESUMO

BACKGROUND: Fungi and insect pests ruin stored crop grain, which results in millions of dollars of damage, presenting an ongoing challenge for farmers in addition to diminishing the safety of stored food. A wide-range defensive system against pathogens is needed to reduce or even eliminate the dependence of the crop yield upon the use of pesticides. Plant defensins (γ-thionins) are antimicrobial peptides (AMPs) that are a component of the host defense system. They are known to interact with cell membranes to exhibit antifungal and insecticidal activity. They exhibit a broad range of activities against fungi and insects and are effective at low concentrations. Thionins act on membranes, greatly reducing the development of pathogen resistance. OBJECTIVE: The aim of this study is to investigate a bioactive molecule that acts against fungal pathogens and stored grain insect pests. METHODS: γ-thionin protein was extracted from Brassica oleracea L. var. capitata f. alba (white cabbage) seed powder in phosphate buffer (100 mM, pH 7.0) and was identified by MALDI-TOF/TOF. The crude extract was subjected to 70% ammonium sulfate saturation followed by gel filtration chromatography. The disc diffusion assay along with a microtiter bioassay was used to determine the antifungal activity of the protein against phytopathogenic fungi. The insecticidal efficacy was evaluated by feeding insect pests with food contaminated with the purified protein. Additionally, an in silico molecular structure prediction study of the protein was performed using Auto Dock Vina for molecular docking of the protein with either fungal membrane moieties or α-amylase from Tenebrio molitor L. MD simulations of protein-ligand complexes were conducted using Schrodinger's Desmond module. RESULTS: γ-Thionin (BoT) was purified from white cabbage seeds and showed 100% homology with thionin (Brassica oleracea L. var. viridis) and 80% homology with defensin-like protein 1 (Raphanus sativus L.), respectively. BoT significantly inhibited the mycelial growth of Aspergillus niger van Tieghem and Aspergillus flavus Link at a concentration of 2 µM. Similarly, 0.12 µM BoT treatment resulted in significant mortality of Tribolium castaneum Herbst and Sitophilus oryzae L. Molecular docking and MD simulation of BoT confirmed the strong binding affinity with fungal membrane moieties (phosphatidylinositol 4,5-bisphosphate and phosphatidic acid), which causes disruption of the cell membrane and leakage of the cellular contents, leading to cell death. BoT blocked the active site of α-amylase, and as a result of the inactivation of this gut enzyme, the digestive systems of insects were disturbed, resulting in their deaths. CONCLUSION: This study revealed that γ-thionin is a good antifungal and insecticidal agent that could be used as an alternate to fungicides and insecticides.


Assuntos
Fungicidas Industriais , Inseticidas , Tioninas , Humanos , Animais , Tioninas/química , Tioninas/farmacologia , Antifúngicos/farmacologia , Antifúngicos/química , Inseticidas/farmacologia , Fungicidas Industriais/farmacologia , Simulação de Acoplamento Molecular , Pós , Ligantes , Sulfato de Amônio , Sementes , Insetos , Defensinas/farmacologia , Defensinas/química , alfa-Amilases , Ácidos Fosfatídicos , Misturas Complexas , Fosfatidilinositóis , Fosfatos
8.
Molecules ; 27(10)2022 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-35630727

RESUMO

Vicilin has nutraceutical potential and different noteworthy medicative health-promoting biotic diversions, and it is remarkable against pathogenic microorganisms and insects. In this study, Vigna aconitifolia vicilin (VacV) has been identified and characterized from the seed of Vigna aconitifolia (Jacq.) Marechal (Moth beans). LC-MS/MS analysis of VacV provided seven random fragmented sequences comprising 238 residues, showing significant homology with already reported Vigna radiata vicilin (VraV). VacV was purified using ammonium sulfate precipitation (60%) followed by size exclusion chromatography on Hi-Load 16/60 Superdex 200 pg column and anion-exchange chromatography (Hi trap Q FF column). Purified VacV showed a major ~50 kDa band and multiple lower bands on 12% sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) under both reduced and non-reduced conditions. After all, a three-dimensional molecular structure of VacV was predicted, which showed ß-sheeted molecular conformation similar to crystallographic structure of VraV. All Vicilins from V. aconitifolia and other plants were divided into six sub-groups by phylogenetic analysis, and VacV shared a high degree of similarity with vicilins of Vigna radiata, Pisum sativum, Lupinus albus, Cicer arietinum and Glycine max. Additionally, VacV (20 µg) has significant growth inhibition against different pathogenic bacteria along strong antifungal activity (50 µg). Likewise, VacV (3.0 mg) produced significant growth reduction in Rice Weevil Sitophilus oryzae larvae after 9 days compared with control. Furthermore, by using MMT assay, the cytotoxicity effect of VacV on the growth of HepG2 liver cancerous cells was tested. VacV showed cytotoxicity against the HepG-2 line and the acquired value was 180 µg after 48 h. Finally, we performed molecular docking against caspase-3 protein (PDB ID: 3DEI) for VacV bioactive receptor interface residues. Hence, our results reveal that VacV, has nutraceutical potential and moth beans can be used as a rich resource of functional foods.


Assuntos
Anti-Infecciosos , Inseticidas , Vigna , Antibacterianos/análise , Anti-Infecciosos/análise , Anti-Infecciosos/farmacologia , Cromatografia Líquida , Inseticidas/análise , Inseticidas/farmacologia , Simulação de Acoplamento Molecular , Filogenia , Proteínas de Plantas/química , Proteínas de Armazenamento de Sementes , Sementes/química , Espectrometria de Massas em Tandem
9.
Sci Rep ; 11(1): 24066, 2021 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-34911985

RESUMO

A potent napin protein has been thoroughly characterized from seeds of rocket salad (Eruca sativa). Eruca sativa napin (EsNap) was purified by ammonium sulfate precipitation (70%) and size-exclusion chromatography. Single intact 16 kDa EsNap band was reduced to 11 and 5 kDa bands respectively on SDS-PAGE. Nano LC-MS/MS yielded two fragments comprising of 26 residues which showed 100% sequence identity with napin-3 of Brassica napus. CD spectroscopy indicated a dominant α-helical structure of EsNap. Monodispersity of EsNap was verified by dynamic light scattering, which also confirmed the monomeric status with a corresponding hydrodynamic radius of 2.4 ± 0.2 nm. An elongated ab initio shape of EsNap was calculated based on SAXS data, with an Rg of 1.96 ± 0.1 nm. The ab initio model calculated by DAMMIF with P1 symmetry and a volume of approx. 31,100 nm3, which corresponded to a molecular weight of approximately 15.5 kDa. The comparison of the SAXS and ab initio modeling showed a minimized χ2-value of 1.87, confirming a similar molecular structure. A homology model was predicted using the coordinate information of Brassica napus rproBnIb (PDB ID: 1SM7). EsNap exhibited strong antifungal activity by significantly inhibiting the growth of Fusarium graminearum. EsNap also showed cytotoxicity against the hepatic cell line Huh7 and the obtained IC50 value was 20.49 µM. Further, strong entomotoxic activity was experienced against different life stages of stored grain insect pest T. castaneum. The result of this study shows insights that can be used in developing potential antifungal, anti-cancerous and insect resistance agents in the future using EsNap from E. sativa.


Assuntos
Albuminas 2S de Plantas/química , Brassica/química , Modelos Moleculares , Conformação Proteica , Sementes/química , Albuminas 2S de Plantas/isolamento & purificação , Albuminas 2S de Plantas/farmacologia , Sequência de Aminoácidos , Antifúngicos/química , Antifúngicos/isolamento & purificação , Antifúngicos/farmacologia , Cromatografia Líquida , Focalização Isoelétrica , Testes de Sensibilidade Microbiana , Proteínas de Plantas/química , Proteínas de Plantas/isolamento & purificação , Espalhamento a Baixo Ângulo , Relação Estrutura-Atividade , Espectrometria de Massas em Tandem , Difração de Raios X
10.
J Affect Disord ; 278: 78-84, 2021 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-32956964

RESUMO

BACKGROUND: The risk factors and adverse outcomes related to maternal depression and child malnutrition are a leading cause of morbidity and mortality in low and middle-income countries (LMIC) including Pakistan. Above 25% of women suffer from maternal depression. Up to 50% children are under-nourished which contributes to 35% of all under-5 deaths in the country. AIM: To determine the efficacy of Learning through Play Plus Thinking Healthy Program (LTP Plus) intervention to reduce maternal depression in mothers with undernourished children. METHODS: In this randomised controlled trial, all eligible mothers presenting to the paediatric departments were invited to participate in the study. Out of the total 256 mothers screened, 107 were included, 54 of those were randomly allocated to LTP Plus group and 53 to treatment as usual (TAU). Edinburgh Postnatal Depression Scale (EPDS) was used to screen for depression. Hamilton Depression Rating Scale (HDRS), Maternal Attachment Inventory (MAI), Social Support Scale (OSLO-3) and the Euro-QoL (EQ-5D) were used to measure the severity of depression, mother-child attachment, level of support and health related quality of life dimensions. Assessments were completed at baseline, end of intervention (3 months from baseline) and at 6 months from baseline. RESULTS: Mothers in the LTP Plus group significantly showed improvements in depression (p<0.001), social support (p = 0.02) and quality of life (p<0.001) at the end of the intervention (LTP Plus), as compared to the TAU group, which were sustained up to 6 months after baseline. CONCLUSION: The outcomes of LTP Plus intervention for mothers of malnourished children show promising results in reducing maternal depression and improving child outcomes. A full trial with longer-term outcomes and cost-effectiveness needs to be conducted.


Assuntos
Transtornos da Nutrição Infantil , Qualidade de Vida , Criança , Depressão/complicações , Depressão/terapia , Feminino , Humanos , Paquistão , Resultado do Tratamento
11.
Turk J Biol ; 44(4): 188-200, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32922126

RESUMO

A Kunitz-type trypsin inhibitor protein has been purified and characterized from seeds of Acacia nilotica L. LC-MS/MS analysis of Acacia nilotica trypsin inhibitor (AnTI) provided the N-terminal fragment of 11 amino acids which yielded 100% identity with already reported Kunitz-type trypsin inhibitor protein of Acacia confusa (AcTI) in UniProtKB database search. SDS-PAGE showed a single band of ~21 kDa under nonreduced condition and appearance of a daughter band (17 kDa) in the presence of ß-mercaptoethanol indicating the presence of interchain disulfide linkage typical for Kunitz-type trypsin inhibitors. AnTI was purified from seed extract by using a combination of anion exchange and gel filtration chromatography. Since AnTI showed maximum homology with AcTI, a molecular structure of AcTI was predicted which showed highly ß-sheeted molecular conformation similar to crystallographic structure of Enterolobium contortisiliquum trypsin inhibitor (EcTI). AnTI (20 µg) produces significant population inhibition against different human pathogenic bacteria along strong antifungal activity (50 µg). Entomotoxin potential of AnTI was evaluated against two stored grain insect pests Tribolium castaneum (Herbst) (Tenebrionidae: Coleoptera) and Sitophilus oryzae (Linnaeus) (Curculionidae: Coleoptera). Statistically significant mortality of T. castaneum adults was observed at 1.5 mg after 15 days in comparison to control. Additionally, number of total eggs, larvae, pupae, adults, and their male/female ratio were also severely reduced in comparison to control. Similarly, two generation progeny of S. oryzae was studied after mixing AnTI with rice kernels. Mean percent mortality of adult population was significantly higher after 9 days of exposure in comparison to control group. AnTI significantly reduced the F1 generation while little mortality was observed for F2 generation. Exploration of such potent molecules is the prerequisite of our time regarding the anticipation of postantibiotic era and the development of insect resistance against chemical pesticides.

12.
Sci Rep ; 10(1): 3444, 2020 02 26.
Artigo em Inglês | MEDLINE | ID: mdl-32103102

RESUMO

Storing grains remain vulnerable to insect pest attack. The present study developed a biopesticide using biomolecules and their encapsulation in nanoparticles. A 25 kDa cysteine protease extracted from seeds of Albizia procera (ApCP) was encapsulated in graphene quantum dots (GQDs). The insecticidal activity of ApCP, with or without GQDs, against two stored grain insect pests, Tribolium castaneum (Herbst) and Rhyzopertha dominica (Fabricius) was explored. Insects were exposed to three concentrations 7.0, 3.5 and 1.7 mg of ApCP per a gram of wheat flour and grains. The insecticidal activity of ApCP encapsulated with GQDs was improved compared to that of ApCP without GQDs for both insect pests. The number of eggs and larvae of T. castaneum was reduced by 49% and 86%, respectively. Larval mortality was increased to 72%, and adult eclosion of T. castaneum was reduced by 98% at a 7.0 mg/g concentration of ApCP with GQDs compared to that of ApCP without GQDs. Exposure to 7.0 mg/g ApCP with GQDs, the number of R. dominica eggs and larvae was reduced by 72% and 92% respectively, larval mortality was increased by 90%, and eclosion was reduced by 97%. The extraction, purification, characterization, quantification and encapsulation of ApCP with GQDs were also studied. Cysteine protease nanocarriers have the potential to control stored grain insect pests.


Assuntos
Besouros/efeitos dos fármacos , Cisteína Proteases/farmacologia , Grafite/química , Pontos Quânticos/química , Albizzia/enzimologia , Albizzia/crescimento & desenvolvimento , Sequência de Aminoácidos , Animais , Besouros/crescimento & desenvolvimento , Cisteína Proteases/química , Cisteína Proteases/isolamento & purificação , Controle de Insetos , Larva/efeitos dos fármacos , Larva/crescimento & desenvolvimento , Pontos Quânticos/toxicidade , Sementes/enzimologia , Alinhamento de Sequência , Tribolium/efeitos dos fármacos , Tribolium/crescimento & desenvolvimento
13.
Saudi J Biol Sci ; 26(7): 1661-1667, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31762641

RESUMO

Different temperature zones have significant impact on the population dynamics of Plutella xylostella. Effective management of P. xylostella requires the knowledge of temperature tolerance by different life stages. In the current study, fitness parameters of diamondback moth were reported by using age-stage, two-sex life table traits at four constant temperatures (15, 20, 25 and 30 °C). The life cycle of P. xylostella was significantly longer at 15 °C. The 20 °C level of temperature was found optimal for fecundity, gross reproductive rate (51.74 offspring) and net reproductive rate (44.35 offspring per individual). The adult pre-oviposition period was statistically at par at all four level of temperatures. However, the survival was maximum at 20 °C as compared to other three temperature ranges. Based on the current study, it was concluded that temperature has a great role in population build-up of P. xylostella and effective management tactics should be applied to prevent significant damage to cabbage and other cruciferous crops when the temperature in the field is near 20 °C.

14.
Saudi J Biol Sci ; 26(7): 1767-1771, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31762656

RESUMO

Cereals are staple food for many countries and are grown on millions of hectares of land, but much of the harvest is wasted due to losses by pests. To minimize these losses, many pesticides are used which are damaging to the environment and human health. There are debates to get rid of these chemicals but they are still in use at large scale. An alternative control strategy for insect pests in storage houses is the use of botanicals. In this study, four plant essential oils, two plant extracts, two herbicides, and two insecticides were used against Tribolium confusum and the comparison of toxicity was made by calculating LC50 and LT50 values. LC50 values were higher for abamectin (2.09-10.23 mg/L) and cypermethrin (3.41-11.78 mg/L) insecticides followed by neem essential oil (7.39-19.24 mg/L) and citrus extract (10.14-24.50 mg/L). However, LC50 values were maximum in case of jaman plant extract (22.38-176.42 mg/L) followed by two herbicides, Logran (19.66-39.72 mg/L) and Topik (29.09-47.67 mg/L) However, LC50 values were higher for topic herbicide (24.098 ppm) and jaman essential oil (16.383 ppm) after four days of treatment. Abamectin and cypermethrin insecticides, neem essential oil and citrus plant extract also killed adults of T. confusum quicker as compared other essential oils, extracts and herbicides. Results revealed that botanical formulations being environmentally safe could be used instead of highly hazardous pesticides for stored products' pests. This study also elaborates the non-host toxicity of herbicides commonly applied in our agroecosystem.

15.
Saudi J Biol Sci ; 26(7): 1804-1808, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31762662

RESUMO

Tribolium castaneum (Herbst) (Coleoptera: Tenebrionidae) is one of the major insect pests of stored grains. Due to export legislation and zero-tolerance for live insect in trade commodities, extensive use of synthetic insecticides is in practice in order to eliminate pest infestations from the lots. Currently, the one and only acceptable chemical to be used in stored grain is phosphine but due to its excessive usage the stored grain pests are becoming resistant against it. Hence discovery of alternative compounds is much needed. In this study we have compared insecticidal efficacy of different plant materials from six commonly grown plants of Pakistan, viz. Allium sativum (Alliaceae), Zingiber officinale (Zingiberaceae), Cymbopogon citratus (Poaceae), Eucalyptus globulus (Myrtaceae), Nicotiana tabacum (Solanaceae), and Azadirachta indica (Meliaceae) against T. castaneum infesting stored wheat, rice, corn and gram pulse. Various plant parts were dried, powdered, and used as admixtures to the stored commodities in the experiments. The results have suggested that A. sativum (garlic) and Z. officinale (ginger) were more effective resulting into 15 times higher adult mortality and 4 to 5 times reduction in grain weight losses when mixed with rice grains. Similarly, A. indica when admixture with wheat checked the population growth in the resources resulting into 3.5 times less adult production compared to controls. A subsequent experiment was conducted to study the dose response of neem seed powder against the beetle pest infesting milled products. Surprisingly, better control was observed either at lowest (1% w/w) or the highest doses (5% w/w). This finding is of great interest to understand the underlying phenomenon which we assume is the ability of T. castaneum to feed selectively in flour mediums, however, further research on this aspect is required to be investigated. The results of this study support the use of botanicals for stored product pest management.

16.
PeerJ ; 7: e7788, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31592168

RESUMO

Cotton leaf curl Multan virus (CLCuMuV) is a serious and economically important viral disease agent in cotton and ornamental plants like Hibiscus in many regions of the world, especially in South Asia. CLCuMuV is transmitted exclusively by Bemisia tabaci cryptic species complex. This virus was recently recorded in southern China, presumably an invasion from South Asia. This study was performed to estimate the efficiency of three species of the B. tabaci whitefly complex (tentatively named as MEAM1, MED and Asia II 7, respectively) to transmit CLCuMuV and Cotton leaf curl multan virus betasatelite (CLCuMuB). Transmission assays and real-time quantitative PCR were conducted using three cultivars of cotton, Gossypium hirsutum, including 112-2, Xinhai-21 and Zhongmian-40. The results indicated that Asia II 7 was able to transmit the virus to two of the cotton cultivars, i.e. 112-2 and Xinhai-21, with the highest transmission efficiencies of 40% and 30%, respectively, but was unable to transmit the virus to the cotton cultivar Zhongmian-40. MEAM1 and MED failed to transmit CLCuMuV and CLCuMuB to any of the three cotton cultivars. After the three cryptic species of whiteflies had fed on virus-infected cotton plants for 48 h, the relative quantity of CLCuMuV in Asia II 7 was detected to be significantly higher than that in both MEAM1 and MED (P < 0.05). These results indicate that among the three species of whiteflies Asia II 7 is likely the most efficient vector for CLCuMuV and CLCuMuB in Malvaceae crops in China. Our findings provide valuable information to the control of viral diseases caused by CLCuMuV in the field.

17.
Ecotoxicol Environ Saf ; 171: 721-727, 2019 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-30658308

RESUMO

Use of insecticides for agricultural pest management have significant environmental impacts. Using integrated approaches to minimize the frequency of insecticide application by incorporating cultural control tactics can keep environmental hazards to the minimum. The alternate hosts of polyphagous pests have significant role in population development and success of chemical control. Spodoptera exigua Hübner is a polyphagous insect pest of frequently cultivated crops (castor, cauliflower, okra and spinach) in cotton agroecosystem of Pakistan. Since the timeline of cultivation of these crops coincide and the field are often adjoining, S. exigua therefore keeps on migrating from one crop to the other both in winter and summer. Such shifting has a significant effect on the susceptibility of the larvae against the commonly used insecticides. To reveal these effects, toxicity of chlorpyrifos and cypermethrin were tested against the larvae fed on their natal hosts, then shifted to their auxiliary hosts and finally upon their reversal to the natal host. Results have demonstrated that resistance of S. exigua decreased significantly when the populations are cultured on a single host in the laboratory. Field population collected from castor crop demonstrated the highest decrease in resistance ratios against chlorpyrifos and cypermethrin (i.e., 210- and 403-folds, respectively) compared to its field population. Moreover, alternation of generations among cotton and alternate crops, in general, decreased the resistance against chlorpyrifos and cypermethrin. But when these populations return to cotton again, their resistance has been found to be increased significantly. A similar but more obvious change in resistance ratio is observed when the pest population from cotton hosts is fed on spinach (a host available in the later developmental stages of cotton) and vice versa upon their return to cotton. Hence it is suggested that for effective management of S. exigua a continual routine of pest control on available alternate hosts, especially castor and spinach should be administered at critical stages of cotton crop development, i.e. early seedling stage and the late fruiting stage.


Assuntos
Agricultura/métodos , Clorpirifos/toxicidade , Gossypium , Resistência a Inseticidas , Inseticidas/toxicidade , Piretrinas/toxicidade , Spodoptera/efeitos dos fármacos , Animais , Ecossistema , Larva/efeitos dos fármacos , Paquistão
18.
Kaohsiung J Med Sci ; 34(12): 673-683, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30527201

RESUMO

The present study describes the predicted model and functional characterization of an endochitinase (30 kDa) from corms of Gladiolus grandiflorus. ESI-QTOF-MS generated peptide showed 96% sequence homology with family 18, Class III acidic endochitinase of Gladiolus gandavensis. Purified G. grandiflorus chitinase (GgChi) hydrolyzed 4-methylumbelliferyl ß-d-N,N',N''-triacetylchitotriose substrate showing specific endochitinase activity. Since no structural details of GgChi were available in the Protein Data Bank (PDB), a homology model was predicted using the coordinate information of Crocus vernus chitinase (PDB ID: 3SIM). Ramachandran plot indicated 84.5% in most favored region, 14.8% in additional and 0.6% in generously allowed region while no residue in disallowed region. The predicted structure indicated a highly conserved (ß/α)8 (TIM barrel) structure similar to the family 18, class III chitinases. The GgChi also showed sequence and structural homologies with other active chitinases. The GgChi (50 µg/disc) showed no antibacterial activity, but did provide mild growth inhibition of phytopathogenic fungus Fusarium oxysporum at a concentration of 500 µg/well Similarly, insect toxicity bioassays of GgChi (50 µg) against nymphs of Bemisia tabaci showed 14% reduction in adult emergence and 14% increase in mortality rate in comparison to control values. The GgChi (1.5 mg) protein showed significant reduction in a population of flour beetle (Tribolium castaneum) after 35 days, but lower reactivity against rice weevil (Sitophilus oryzae). The results of this study provide detai.led insight on functional characterization of a family 18 class III acidic plant endochitinase.


Assuntos
Quitinases/química , Quitinases/metabolismo , Iridaceae/enzimologia , Modelos Moleculares , Proteínas de Plantas/química , Proteínas de Plantas/metabolismo , Sequência de Aminoácidos , Animais , Antibacterianos/farmacologia , Antifúngicos/farmacologia , Bactérias/efeitos dos fármacos , Quitinases/isolamento & purificação , Bases de Dados de Proteínas , Ensaios Enzimáticos , Fungos/efeitos dos fármacos , Hemípteros/efeitos dos fármacos , Inseticidas/toxicidade , Testes de Sensibilidade Microbiana , Proteínas de Plantas/isolamento & purificação , Espectrometria de Massas por Ionização por Electrospray , Homologia Estrutural de Proteína
19.
J Child Health Care ; 21(3): 331-342, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29119823

RESUMO

Malnutrition is a primary cause of child morbidity and mortality. The effects of maternal depressive symptoms on children's health, especially their nutritional status, have received less attention in developing countries but needs to be evaluated to understand the public health implications of maternal depression. The aim of the current study was to investigate the association between maternal depressive symptoms and children's nutritional status using data from low socioeconomic community in Pakistan. Maternal depressive symptoms defined as Aga Khan University Anxiety and Depression Scale score of 20 or greater was assessed for mothers with children under two years of age. Logistic regression models estimated the association between maternal depressive symptoms and stunting and underweight. Of 325 mothers, 40% scored positive on the depressive scale. The prevalence of stunting and underweight in children under two years was 36.6% and 35.4%, respectively. Maternal depressive symptoms were significantly associated with children being stunted and underweight. Mothers with depressive symptoms were more than three times likely to have stunted (odds ratio (OR) 3.15, 95% confidence interval (CI) 1.91-5.18, p value < .001) and underweight (OR 3.26, 95% CI 1.99-5.34, p value < .001) children compared to non-depressed mothers. Maternal-related factors such as poor education, unemployment, and low household income were found to be significantly associated with higher odds of children's short stature and underweight.


Assuntos
Depressão/psicologia , Transtornos do Crescimento , Mães/psicologia , Estado Nutricional/fisiologia , Magreza , Adulto , Estudos Transversais , Feminino , Humanos , Lactente , Paquistão , Pobreza , Inquéritos e Questionários , Populações Vulneráveis
20.
Environ Entomol ; 46(3): 595-601, 2017 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-28383691

RESUMO

Spodoptera exigua (Hübner) is a polyphagous pest that shifts its population to different hosts during its life cycle to receive nutritive advantages. Therefore, demographic evaluation of alternate hosts is important for effective pest management. Here, we have evaluated castor (Ricinus communis L.), cauliflower (Brassica oleracea L.), cotton (Gossypium hirsutum L.), okra (Abelmoschus esculentus L.), and spinach (Spinacia oleracea L.) for growth, survival, and population development of S. exigua. Development of early populations of S. exigua is best supported on castor where earlier instars had least mortalities (10%) compared with spinach (36%), although later instars and pupae had significantly higher mortalities (20.8%) on it. Spinach and okra, on the other hand, promote larval survivals in later instars. Little or no differences in stadia lengths were observed during early development of larvae and, interestingly, the longevity of female moths increased significantly when reared on castor, cauliflower, and spinach (12.3, 11.3, and 11.7 d, respectively), resulting into significantly higher fecundity. The survival curves of all five populations have clearly demonstrated a steep early decline in larval numbers when reared on okra and only 60% larvae could survive. These findings conclude that S. exigua when fed on spinach was greatly disadvantaged in terms of growth and development; hence, the pest's field population can be opportunistically controlled by spraying adjacent spinach fields. In addition, the results highlight the vulnerable stages in pest's life cycle in the field where we can apply integrated control strategies for its effective management.


Assuntos
Gossypium , Controle de Insetos/métodos , Spodoptera/crescimento & desenvolvimento , Animais , Produtos Agrícolas/crescimento & desenvolvimento , Feminino , Gossypium/crescimento & desenvolvimento , Larva/crescimento & desenvolvimento , Masculino , Pupa/crescimento & desenvolvimento
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