Synthesis, biological activities, and structure-activity relationships of Morita-Baylis-Hillman adducts: An update.

The Morita-Baylis-Hillman (MBH) reaction is a unique C-C bond-forming technique for the generation of multifunctional allylic alcohols (MBH adducts) in a single operation. In recent years, these MBH adducts have emerged as a novel class of compounds with significant biological potential, including anticancer, anti-leishmanial, antibacterial, antifungal, anti-herbicidal effects and activity against Chagas disease, and so on. The aim of this review is to assimilate the literature findings from 2011 onwards related to the synthesis and biological potential of MBH adducts, with an emphasis on their structure-activity relationships (SAR). Although insight into the biological mechanisms of action for this recently identified pharmacophore is currently in its nascent stages, the mechanisms described so far are reviewed herein.

Residue behaviour and health risk assessment of chlorpyrifos and mancozeb in apple fruits and soil.

Mancozeb residue estimation was done using second derivative ultraviolet spectroscopy by Shimadzu ultraviolet-visible spectrophotometer, and chlorpyrifos was estimated by QuEChERS technique using GC-FPD. The persistence for chlorpyrifos was carried out at two locations, and for mancozeb, persistence studies were carried out at four locations. Initial deposits of mancozeb on apple fruits ranged from 1.33 to 1.63 mg/kg at the recommended dose and from 2.55 to 3.26 mg/kg at double the recommended dose at all four locations. Chlorpyrifos residues in apple fruits had an initial deposit of 0.94-0.99 mg/kg at recommended dose and 1.75-1.92 mg/kg at double the recommended dose. Mancozeb residues in apple fruit were below the detection limit (BDL) after 20 days at recommended dose and after 25 days at double the recommended dose at two locations, while mancozeb residue at the other two locations and the residues of chlorpyrifos at all locations reached BDL after 15 and 20 days at recommended and double the recommended doses, respectively. Half-life of mancozeb varied from 3.07 to 4.02 days at recommended dose and from 3.30 to 4.32 days at double the recommended dose, whereas chlorpyrifos residues dissipated to half their initial concentration on 2.33-2.35 days at recommended dose and 2.89-2.90 days at double the recommended dose. The soil samples showed no presence of residues of chlorpyrifos and mancozeb at harvest. The risk assessment revealed that hazard quotient for the intake of mancozeb was in the range of 0.06-0.13% and 0.20-0.44% for rural and urban population, while for the intake of chlorpyrifos, hazard quotient was in the range of 0.10-0.12% for rural population and 0.33-0.38% for urban population, and theoretical maximum dietary intake (9.67 × 10-5 mg/person and 3.18 × 10-4 mg/person for rural population and urban population in case of mancozeb and 3.22 × 10-5 mg/person and 1.06 × 10-4 mg/person for rural population and urban population in case of chlorpyrifos) was also found to be less than maximum permissible intake (1.38 mg/kg for mancozeb and 0.60 mg/kg for chlorpyrifos). The results of risk assessment thereby indicated that apple consumption does not pose a risk to human health.

Dissipation pattern and dietary risk assessment of some commonly used insecticides on tomato (Solanum lycopersicum L.).

Pesticide residue in food commodities is a serious concern in relation to consumer safety and also the most significant barrier in the trade of food commodities. The dissipation pattern of four insecticides, namely novaluron, λ-cyhalothrin, imidacloprid, and fenazaquin, was evaluated on tomato fruits and cropped soil. The residues were extracted using the QuEChERS analytical method and quantized using a gas chromatograph with electron capture detector, gas chromatograph mass spectrometer, and high-performance liquid chromatography with photo diode array detector. The analytical method was validated using parameters like recovery, linearity, accuracy, matrix effect, and specificity, with limit of detection and limit of quantitation established to be 0.01 and 0.05 mg/kg, respectively, for all the pesticides. The average initial deposits (samples collected after 2 h of application) at the recommended dose of novaluron, λ-cyhalothrin, imidacloprid, and fenazaquin were 0.593, 0.293, 0.227, and 0.431 mg/kg on tomato fruits, respectively, and were below the limit of quantification in soil. The pre-harvest interval of 17, 8, 1, and 13 days was suggested for novaluron, λ-cyhalothrin, imidacloprid, and fenazaquin on tomato, respectively. Risk assessment studies revealed that all pesticides under study are safe and do not pose any threat to humans as theoretical maximum dietary intake is less than the maximum permissible intake and acceptable daily intake.

Silver Nanoparticles and Its Mechanistic Insight for Chronic Wound Healing: Review on Recent Progress.

Wounds are structural and functional disruptions of skin that occur because of trauma, surgery, acute illness, or chronic disease conditions. Chronic wounds are caused by a breakdown in the finely coordinated cascade of events that occurs during healing. Wound healing is a long process that split into at least three continuous and overlapping processes: an inflammatory response, a proliferative phase, and finally the tissue remodeling. Therefore, these processes are extensively studied to develop novel therapeutics in order to achieve maximum recovery with minimum scarring. Several growth hormones and cytokines secreted at the site of lesions tightly regulates the healing processes. The traditional approach for wound management has been represented by topical treatments. Metal nanoparticles (e.g., silver, gold and zinc) are increasingly being employed in dermatology due to their favorable effects on healing, as well as in treating and preventing secondary bacterial infections. In the current review, a brief introduction on traditional would healing approach is provided, followed by focus on the potential of wound dressing therapeutic techniques functionalized with Ag-NPs.

Morita-Baylis-Hillman reaction of 3-formyl-9H-pyrido[3,4-b]indoles and fluorescence studies of the products.

ß-Carboline is a privileged class of the alkaloid family and is associated with a broad spectrum of biological properties. 3-Formyl-9H-pyrido[3,4-b]indole is a such potent precursor belonging to this family which can be tailored for installing diversity at various positions of ß-carboline to generate unique molecular hybrids of biological importance. The present work is a step towards this and assimilates the results related to the exploration of 3-formyl-9H-ß-carbolines for the synthesis of ß-carboline C-3 substituted MBH adducts followed by evaluation of their fluorescent characteristic. The effect of contact time, solvent system, concentration and substituents was also studied during investigation of fluorescence properties of these derivatives.

Dissipation kinetics and dietary risk assessment of spiromesifen on major summer vegetables using good agricultural practices.

Dissipation kinetics and dietary risk assessment of spiromesifen is worked out on four summer vegetables, viz. okra, chilli, capsicum and brinjal (eggplant or aubergine) during March-April 2015 at the experimental farm of the Department of Entomology, Dr. Yashwant Singh Parmar University of Horticulture and Forestry Nauni, Solan using good agricultutral practices. Two foliar applications of spiromesifen @ 144.0 g.a.i./ha each were given at 10 days interval with a knapsack sprayer with the first application at the fruit initiation stage. Sample were collected up to 15 days after pesticide application and processed using a modified QuEChERS method, which was validated by doing recovery studies having recovery range and RSD within established guidelines of SANCO. Estimation of spiromesifen residues was conducted on GC-MS. The initial deposits after spraying of spiromesifen on okra, capsicum, chilli and brinjal fruit after 2 h of treatment were 1.327, 0.727, 0.800 and 0.738 mg/kg, respectively. The residues persisted up to 7 days and further dissipated and declined below the limit of quantification of <0.025 mg/kg at 10 days after treatment in all of the crops under investigation. Dissipation of spiromesifen followed first-order kinetics. The spiromesifen residues dissipated to half in 1.6, 1.8, 1.9 and 1.7 days with the suggested safe waiting period of 8.9, 5.2, 6.0 and 7.0 in the respective crops. The hazard quotient was <1 and theoretical maximum dietary intake was less than the maximum permissible intake, which was less than the maximum residue limit in all of the vegetable crops under investigation.

Genetic diversity of X-STR markers in Jat Sikh population of Punjab, India and its comparison with other 39 global populations.

BACKGROUND: The Jat Sikh population is the largest endogamous group of Punjab, a state in north-west India, and has not yet been explored for genetic polymorphism based on X-STR genetic markers. In India, which is the second most populous country in the world, only two population studies based on X-STR markers have been reported so far. AIM: To explore the genetic diversity of 12 X chromosomal STR genetic markers in the Jat Sikh population of Punjab and expand the X-STR polymorphism database. SUBJECTS AND METHODS: In this study, a total of 200 Jat Sikh individuals (100 males and 100 females) residing in Punjab were investigated for 12 X-STR markers using the Investigator Argus X-12 QS Kit. RESULTS: The highest power of discrimination (PD) in females (PDf) and males (PDm) was observed to be 0.965 (DXS10135) and 0.929 (DXS10135 and DXS10148), respectively. DXS10135 was found to be the most polymorphic and discriminating locus among all the studied loci in both males and females with highest values of power of discrimination (PD) and polymorphic information content (PIC) as well. CONCLUSION: Overall, the studied markers of the Argus 12 X-STR kit provide high polymorphic information which may prove to be an important tool in resolving issues such as missing person identification, incest, immigration disputes, kinship analysis and genealogical studies. The dataset obtained from this study will add to the present database of X-STRs.

Phytochemicals as multi-target inhibitors of the inflammatory pathway- A modeling and experimental study.

The arachidonic acid pathway consists of several enzymes and targeting them is favored for developing anti-inflammatory drugs. However, till date the current drugs are generally active against a single target, leading to undesirable side-effects. Phytochemicals are known to inhibit multiple targets simultaneously and hence, an attempt is made here to investigate their suitability. A pharmacophore based study is performed with three sets of reported phytochemicals namely, dual 5-LOX/mPGES1, alkaloids and FLAP inhibitors. The analysis indicated that phenylpropanoids (including ferulic acid) and benzoic acids derivatives, and berberine mapped onto these pharmacophores with three hydrophobic centroids and an acceptor feature. 2,4,5-trimethoxy (7) and 3,4-dimethoxy cinnamic acids (8) mapped onto all the three pharmacophores. Experimental studies indicated that berberine inhibited 5-LOX (100 µM) and PGE2 (50 µM) production by 72.2 and 72.0% and ferulic acid by 74.3 and 54.4% respectively. This approach offers a promising theoretical combined with experimental strategy for designing novel molecules against inflammatory enzymes.

Natural product inspired design and synthesis of ß-carboline and γ-lactone based molecular hybrids.

ß-Carboline and γ-lactone moieties have been selected by nature as privileged scaffolds and display a wide range of pharmacological properties. Following nature, we envisaged the preparation of new ß-carboline and γ-lactone based molecular hybrids incorporating both the pharmacophores. In this regard, a water-assisted In-mediated environmentally benign and easy to execute single-step tandem Barbier type allylation-lactonisation process has been devised in order to afford the targeted molecular architectures. It is anticipated that aqueous medium plays the key role in allylation as well as in the subsequent lactonisation process for the diastereo-selective synthesis of these conjugates. It is believed that water drives the reaction pathway through dual activation, it increases the electrophilic character of formyl and ester functionalities and simultaneously enhances the nucleophilic potential of the hydroxyl group to facilitate the in situ intramolecular condensation. Importantly, during this synthetic strategy no column chromatographic purification was required at any stage.

Correction: Rani et al. Nematicidal Potential of Green Silver Nanoparticles Synthesized Using Aqueous Root Extract of Glycyrrhiza glabra. Nanomaterials 2022, 12, 2966.

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Unveiling the dynamic relationship of viruses and/or symbiotic bacteria with plant resilience in abiotic stress.

In the ecosphere, plants interact with environmental biotic and abiotic partners, where unbalanced interactions can induce unfavourable stress conditions. Abiotic factors (temperature, water, and salt) are primarily required for plants healthy survival, and any change in their availability is reflected as a stress signal. In certain cases, the presence of infectious pathogens such as viruses, bacteria, fungi, protozoa, nematodes, and insects can also create stress conditions in plants, leading to the emergence of disease or deficiency symptoms. While these symptoms are often typical of abiotic or biotic stress, however, there are instances where they can intensify under specific conditions. Here, we primarily summarize the viral interactions with plants during abiotic stress to understand how these associations are linked together during viral pathogenesis. Secondly, focus is given to the beneficial effects of root-associated symbiotic bacteria in fulfilling the basic needs of plants during normal as well as abiotic stress conditions. The modulations of plant functional proteins, and their occurrence/cross-talk, with pathogen (virus) and symbiont (bacteria) molecules are also discussed. Furthermore, we have highlighted the biochemical and systematic adaptations that develop in plants due to bacterial symbiosis to encounter stress hallmarks. Lastly, directions are provided towards exploring potential rhizospheric bacteria to maintain plant-microbes ecosystem and manage abiotic stress in plants to achieve better trait health in the horticulture crops.

Residue estimation and dietary risk assessment of fenvalerate, novaluron, and profenofos in bell pepper grown under protected and open field conditions.

Residue studies were conducted in bell pepper crops (green and yellow bell pepper) to ensure the safe use of fenvalerate, profenofos, and novaluron (under open field and protected conditions) in randomized block design (RBD) following three applications at a 10-day interval over two consecutive years, 2021 and 2022. A robust analytical method was developed using quick, easy, cheap, effective, rugged, and safe (QuEChERS) extraction and gas chromatography-tandem mass spectrometry (GC-MS/MS) for the determination of pesticide residues in bell pepper samples. The half-lives for fenvalerate were 2.47-2.87 and 2.50-3.03 days on bell pepper under open field conditions, whereas the corresponding values for bell pepper under protected conditions were 3.84-4.58 and 4.17-4.71 days, during 2021 and 2022, respectively. Profenofos displayed half-lives of 2.03-2.65 and 2.15-2.77 days in open field conditions and 3.05-3.89 and 3.16-3.78 days in protected conditions during 2021 and 2022, respectively. Similarly, novaluron had half-lives of 2.87-3.49 and 3.24-3.75 days under protected conditions in 2021 and 2022, respectively. The maximum residue limits (MRLs) were calculated to be 0.6 mg/kg for fenvalerate, while for profenofos it was 0.7 mg/kg on bell pepper under open field conditions at double doses, at the proposed pre-harvest interval (PHI) of 3 days. Likewise, for bell peppers grown under protected conditions, MRLs at the PHI of 3 days were determined to be 0.8 mg/kg for fenvalerate, 0.3 mg/kg for novaluron, and 1.5 mg/kg for profenofos. A dietary risk assessment study indicated that the percentage of acute hazard index (% aHI) was significantly lower than 100, and hazard quotient (HQ) values were below 1, signifying no acute or chronic risk to consumers. These findings underscore the safety of consuming bell peppers treated with fenvalerate, profenofos, and novaluron under the protected and open field conditions.

Residue behavior and consumer risk assessment of spirotetramat and chlorpyrifos on cabbage heads and cropped soil.

A field experiment following good agricultural practices was laid out to study the dissipation of spirotetramat (90 g a.i. ha-1 and 180 g a.i. ha-1) and chlorpyrifos (400 g a.i. ha-1 and 800 g a.i. ha-1) on cabbage heads and soil. Samples were processed using quick, easy, cheap, effective, rugged, and safe (QuEChERS) method for residue estimation of spirotetramat and chlorpyrifos, which were further detected using HPLC-PDA and GC-FPD respectively. The residues of spirotetramat on cabbage heads reached below detection limit (BDL) (< 0.05 mg kg-1) on 7th and 10th day and for chlorpyrifos, BDL (< 0.01 mg kg-1) was achieved on 10th and 15th day for X and 2X dose, respectively. On 20th day after second spray, residues in soil were found to be BDL for both the pesticides. Half-life of spirotetramat and chlorpyrifos was found to be 3 and 2 days, respectively while a safe pre-harvest interval (PHI) of 9 days for spirotetramat and 10 days for chlorpyrifos is suggested on cabbage. The dietary risk assessment studies for various age groups of Indian population, ascertained safety of treated cabbage heads for consumption, as current study revealed that hazard quotient (HQ) < 1 and theoretical maximum dietary intake (TMDI) < maximum permissible intake (MPI) for both the pesticides at respective PHI.

Nanoformulation of a Trypanocidal Drug Isometamidium Chloride Ameliorates the Apurinic-Apyrimidinic DNA Sites/Genotoxic Effects in Horse Blood Cells.

Isometamidium chloride (ISM) is a trypanocide for the prophylactic and therapeutic use against vector-borne animal trypanosomosis (mainly Surra caused by Trypanosoma evansi) and African animal trypanosomosis caused by T. congolense/T. vivax/T. brucei). ISM was found to be an efficient trypanocide for therapeutic/prophylactic use against trypanosomosis; however, it produces some local and systemic detrimental effects in animals. We synthesized isometamidium chloride-loaded alginate gum acacia nanoformulation (ISM SANPS) to lessen the detrimental side effects of isometamidium chloride (ISM) while treating trypanosomal diseases. We intended to determine the cytocompatibility/toxicity, and DNA deterioration/chromosomal structural or number changes (genotoxicity) of ISM SANPs using mammalian cells in a concentration-dependent manner. Apurinic/apyrimidinic (AP) sites are one of the major types of DNA lesions formed during base excision and repair of oxidized, deaminated, or alkylated bases. The intensity of the cellular AP site is an excellent marker of the deterioration of DNA quality. We thought it pertinent to quantify the AP sites in ISM SANPs-treated cells. Our investigations established a dose-dependent cyto-compatibility or toxicity and DNA impairment (genotoxicity) in ISM SANPs-treated horse peripheral blood mononuclear cells. ISM SANPs were biocompatible at various concentrations tested on the mammalian cells.

Bio-Fabrication of Euryale ferox (Makhana) Leaf Silver Nanoparticles and Their Antibacterial, Antioxidant and Cytotoxic Potential.

Bio-fabrication of green or plant extract-based silver nanoparticles has garnered much praise over the past decade as the methodology is environment-friendly, undemanding, non-pathogenic, and economical. In the current study, leaves of Eurale ferox (Makhana), considered as waste, were used for the bio-fabrication of silver nanoparticles (ELAgNPs). Various analytical techniques including UV−VIS spectroscopy, Field emission scanning electron microscopy equipped with an energy dispersive X-ray spectrometer (FESEM-EDX), Particle size analyzer (PSA), Fourier transform infra-red spectroscopy (FTIR) and high-resolution transmission electron microscopy (HRTEM) were used for their characterization. Their antibacterial efficacy was examined against gram positive bacterium, Bacillus subtilis and gram negative bacterium, Escherichia coli. The antioxidant potential of the ELAgNPs was compassed by 2, 2 diphenyl-1-picryl hydrazyl (DPPH; λmax = 517 nm) assay, H2O2 (λmax = 230 nm) and OH− (λmax = 520 nm)-based radical scavenging assays. The cytotoxicity was checked against the VERO cell line using 3-[4, 5-dimethyl thiazol-2-yl]-2, 5 diphenyl tetrazolium bromide (MTT) assay. A mean particle size of 26.51 ± 8.87 nm with a size distribution of 7.08−53.94 nm was obtained using HRTEM. The ELAgNPs exhibited dose-dependent antibacterial efficacy with a maximum zone of inhibition (ZOI) of 21.98 ± 0.59 mm against B. subtilis and of 16.46 ± 0.22 mm against E. coli at 500 ppm after 24 h of incubation. The median lethal concentration for the cytotoxicity analysis was found to be 9.54 ± 0.35 ppm, 120.9 ± 6.31 ppm, and 20.74 ± 0.63 ppm for ELAgNPs, commercial silver nanoparticles (CAgNPs), and silver nitrate (SN), respectively. The ordinary one-way ANOVA results exhibited a significant decrease in cell viability after 72 h of incubation at p < 0.05, α = 0.05. In conclusion, the ELAgNPs showed good antibacterial, radical scavenging and dose-dependent cytotoxicity against the VERO cells. Therefore, these could be used for biomedical applications. Phyto-constituents present in the plant not only act as reducing agents but also as stabilizing and coating agents, and the availability of a wide range of metabolites makes the green approach more promising.

Nematicidal Potential of Green Silver Nanoparticles Synthesized Using Aqueous Root Extract of Glycyrrhiza glabra.

Meloidogyne incognita (root-knot nematode) is a devastating soil-borne pathogen which can infect almost all cultivated plants around the globe, expediting huge pecuniary losses. The purpose of current study was to use the aqueous root extract of Glycyrrhiza glabra for synthesizing silver nanoparticles (GRAgNPs) and assess their nematicidal potential against M. incognita by in vitro methods, including hatching inhibition and mortality assays. The active uptake of FITC labeled GRAgNPs by the nematode and their effect on the expression of selected genes involved in oxidative stress and DNA damage repair were also studied. An HRTEM micrograph confirmed their spherical morphology with sizes ranging from 9.61 nm to 34.735 nm. Complete inhibition of egg-hatching was observed after 48 h of treatment with as low as 10.0 ppm of GRAgNPs. In addition, 100% mortality was recorded at the lowest dose of 6.0 ppm, after 12 h of treatment. The LC-50 for GRAgNPs was found to be 0.805 ± 0.177 ppm at p < 0.0001, R2 = 0.9930, and α = 0.05. The expression of targeted genes (skn-1, mev-1, sod-3, dhs-23, cyp-450, xpa, cpr-1, gst-n, and ugt) was significantly enhanced (1.09−2.79 folds), at 1.0 ppm (α = 0.05, 95% CI) GRAgNPs treatment. In conclusion, GRAgNPs performed efficaciously and considerably in contrast to chemical nematicide and commercial silver nanoparticles (CAgNPs) and might be used as a promising alternative as relatively lower concentration and short exposure time were enough to cause higher mortality and nanotoxicity in nematodes.

Y-23 mediated genetic data analysis of endogamous Brahmin population of Rajasthan, India.

India's largest state Rajasthan is known for its variable population groups including castes, communities and tribes. In the present article, Y-STR polymorphisms of hundred unrelated healthy male volunteers from the Brahmin population of Rajasthan, India were investigated using the Powerplex® Y-23 PCR amplification kit. Total 94 distinct haplotypes were obtained out of them 93 were singletons. Haplotype Diversity (HD) and Discrimination Capacity (DC) for the population were 0.644 and 0.9894 respectively. The Intra-population relationship between the present population data and other reported Indian populations was examined through Multidimensional Scaling (MDS) Plot, which shows the Brahmin population of Rajasthan lies in a cluster with the Brahmin populations of Haryana and Maharashtra. Data generated with 23 Y-STR markers is submitted on Y chromosome haplotype reference database (YHRD) (yhrd.org) and it will robust the forensic database of the Rajasthan population of India.

Glycyrrhiza glabra: An Insight to Nanomedicine.

Glycyrrhiza glabra Linn (Fabaceae), commonly known as Licorice/Liquorice, Mulahatti; is an undershrub. The dried, peeled or unpeeled underground stems and roots are used for the treatment of upper respiratory tract ailments, immunodeficiency, endocrine disorders, skin, liver, joint and heart diseases. Medicinal properties of this plant are enormous and offer it as one of the greatest candidates in the field of Nanomedicine. The Nanomedicine has dedicated to safeguard and upgrade human health using the nanotechnology. Bioactive constituents of this plant perform versatile pharmacological actions and can be used as good Bioanalytical tools. Therefore, an updated overview on current knowledge of green synthesis of nanoparticles (NPs), nanoformulations and surface modification using G. glabra is provided here in order to explore its therapeutic potential especially antifungal and antibacterial activities. In our lab, we have synthesized silver nanoparticles (Ag NPs) using leaves and rhizome parts of G. glabra.

Herbal Medicine for Urinary Tract Infections with the Blazing Nanotechnology.

Medicinal plants have been an integral and essential part of human life since ancient times. These have shaped the cultures around the globe. From underlings to elderly persons, everyone has come across to use herbal medicine for minor infection to deadly diseases. A wholesome approach is needed to maximize the knowledge about traditional resources. Thus, combining it with the new advents of technology is miraculous. Urinary tract infections (UTIs) are among the prevalent infections in the world. Increasing multi-drug resistance among uropathogens is quite problematic. The burning field of nanotechnology offers an enormous help in revolutionizing the diagnosis and treatment of the disease. The nanoparticles and nanocarriers can increase the bioavailability and efficacy of phytoconstituents targeted against the uropathogens. The present review focuses on herbal medicine and nanomaterials like nanoparticles, nanocarriers, nanoantibiotics as potent anti-bacterial agents against urinary tract infections.

Persistence and dissipation kinetics of tebuconazole in apple, tomato, chilli and onion crops of Himachal Pradesh, India.

Tebuconazole is a broad-spectrum fungicide extensively used worldwide for the control of many diseases such as powdery mildew and scab in apple, early blight of tomato, anthracnose of chilli, white rot and purple blotch of onion etc. Maximum residue level of this compound has not been worked out on these crops in India; the persistence and dissipation kinetics of tebuconazole on apple, tomato, chilli and onion were studied following three foliar applications of the formulation Folicur 430 SC at a standard dose (X) 322, 268.75, 215 and 215 g a.i./ha and at double dose (2X) 645, 537.5, 430 and 430 g a.i./ha, respectively, to work out the safe waiting periods and half-life period of tebuconazole. Extraction was done using QuEChERS method and cleanup by using dispersive solid-phase method. Tebuconazole residues were estimated on gas chromatograph-mass spectrometry (GC-MS). The recovery of tebuconazole in fortified matrix was above 90% with a limit of quantification (LOQ) at 0.05 mg kg-1. The initial deposits of tebuconazole on apple at two locations under study ranged from 1.986-2.011 mg kg-1at X dose to 3.698-3.843 mg kg-1 at 2X dose. The initial deposits in tomato, chilli and onion were 1.129, 1.760 and 1.169 mg kg-1 at X dose and 2.213, 2.784 and 2.340 mg kg-1, respectively at the 2X dose. Dissipation of the fungicide followed first-order of kinetics and the half life of degradation ranged from 1.30-2.25 days at X dose to 1.40-2.62 days at 2X days on different crops under study. Residues declined below the determination limit (LOQ) of 15 and 20 days after spraying, respectively, at X and 2X dose in apple; 7 and 10 days in tomato; 10 and 15 days in chilli and onion. Waiting periods of 5, 2, 7 and 12 days, respectively, are suggested for apple, tomato, chilli and onion at 2X dose.