Preclinical evaluation of dalbergin loaded PLGA-galactose-modified nanoparticles against hepatocellular carcinoma via inhibition of the AKT/NF-κB signaling pathway.

Prior research has shown the effectiveness of dalbergin (DL), dalbergin nanoformulation (DLF), and dalbergin-loaded PLGA-galactose-modified nanoparticles (DLMF) in treating hepatocellular carcinoma (HCC) cells. The present investigation constructs upon our previous research and delves into the molecular mechanisms contributing to the anticancer effects of DLF and DLMF. This study examined the anti-cancer effects of DL, DLF, and DLMF by diethyl nitrosamine (DEN)-induced HCC model in albino Wistar rats. In addition, we performed biochemical, antioxidant, lipid profile tests, and histological studies of liver tissue. The anticancer efficacy of DLMF is equivalent to that of 5-fluorouracil, a commercially available therapy for HCC. Immunoblotting studies revealed a reduction in the expression of many apoptotic markers, such as p53, BAX, and Cyt-C, in HCC. Conversely, the expression of Bcl-2, TNF-α, NFκB, p-AKT, and STAT-3 was elevated. Nevertheless, the administration of DL, DLF, and DLMF effectively controlled the levels of these apoptotic markers, resulting in a considerable decrease in the expression of Bcl-2, TNF-α, NFκB, p-AKT, and STAT-3. Specifically, the activation of TNF-alpha and STAT-3 triggers the signalling pathways that include the Bcl-2 family of proteins, Cyt-C, caspase 3, and 9. This ultimately leads to apoptosis and the suppression of cell growth. Furthermore, metabolomic analysis using 1H NMR indicated that the metabolites of animals reverted to normal levels after the treatment.

Identification and characterization of GSK-9089 metabolites through high resolution-mass spectrometry based in vitro and in vivo rat biological sample analysis.

Estrogen related receptors (ERRs) agonist GSK-9089 (DY-131) reported to pose a potential in increasing exercise endurance. High resolution mass spectrometry (HRMS) based analysis has utmost importance in the detection, identification, or characterization of a molecule including its metabolites in human body. In this study, in vitro metabolism profile of GSK-9089 was investigated after incubation with liver microsomes and S9 fractions. Additionally, in vivo metabolites of the molecule were identified in plasma, urine, and faeces samples of rats. Structures of all the potential metabolites were revealed by employing an in silico tool and HRMS based analysis through data-dependent and data-independent mining strategies. Nine unknown metabolites of GSK-9089 have been identified which were found to be present in a trace amount in in vivo matrices. Most of the in vitro and in vivo phase I metabolites of the molecule were formed after imine bond hydrolysis followed by deamidation, oxidation, and N-oxidation. The molecule underwent phase II metabolism to generate more polar metabolites mainly through glucuronide, sulfate conjugation biotransformation reactions. The in vitro and in vivo metabolites of GSK-9089 could be useful to identify the abuse of this ERRs agonist in the future.

Genome and transcriptome based comparative analysis of Tilletia indica to decipher the causal genes for pathogenicity of Karnal bunt in wheat.

Tilletia indica Mitra causes Karnal bunt (KB) in wheat by pathogenic dikaryophase. The present study is the first to provide the draft genomes of the dikaryon (PSWKBGD-3) and its two monosporidial lines (PSWKBGH-1 and 2) using Illumina and PacBio reads, their annotation and the comparative analyses among the three genomes by extracting polymorphic SSR markers. The trancriptome from infected wheat grains of the susceptible wheat cultivar WL711 at 24 h, 48h, and 7d after inoculation of PSWKBGH-1, 2 and PSWKBGD-3 were also isolated. Further, two transcriptome analyses were performed utilizing T. indica transcriptome to extract dikaryon genes responsible for pathogenesis, and wheat transcriptome to extract wheat genes affected by dikaryon involved in plant-pathogen interaction during progression of KB in wheat. A total of 54, 529, and 87 genes at 24hai, 48hai, and 7dai, respectively were upregulated in dikaryon stage while 21, 35, and 134 genes of T. indica at 24hai, 48hai, and 7dai, respectively, were activated only in dikaryon stage. While, a total of 23, 17, and 52 wheat genes at 24hai, 48hai, and 7dai, respectively were upregulated due to the presence of dikaryon stage only. The results obtained during this study have been compiled in a web resource called TiGeR ( http://backlin.cabgrid.res.in/tiger/ ), which is the first genomic resource for T. indica cataloguing genes, genomic and polymorphic SSRs of the three T. indica lines, wheat and T. indica DEGs as well as wheat genes affected by T. indica dikaryon along with the pathogenecity related proteins of T. indica dikaryon during incidence of KB at different time points. The present study would be helpful to understand the role of dikaryon in plant-pathogen interaction during progression of KB, which would be helpful to manage KB in wheat, and to develop KB-resistant wheat varieties.

Enhanced Domain Adaptation for Foot Ulcer Segmentation Through Mixing Self-Trained Weak Labels.

Wound management requires the measurement of the wound parameters such as its shape and area. However, computerized analysis of the wound suffers the challenge of inexact segmentation of the wound images due to limited or inaccurate labels. It is a common scenario that the source domain provides an abundance of labeled data, while the target domain provides only limited labels. To overcome this, we propose a novel approach that combines self-training learning and mixup augmentation. The neural network is trained on the source domain to generate weak labels on the target domain via the self-training process. In the second stage, generated labels are mixed up with labels from the source domain to retrain the neural network and enhance generalization across diverse datasets. The efficacy of our approach was evaluated using the DFUC 2022, FUSeg, and RMIT datasets, demonstrating substantial improvements in segmentation accuracy and robustness across different data distributions. Specifically, in single-domain experiments, segmentation on the DFUC 2022 dataset scored a dice score of 0.711, while the score on the FUSeg dataset achieved 0.859. For domain adaptation, when these datasets were used as target datasets, the dice scores were 0.714 for DFUC 2022 and 0.561 for FUSeg.

Interacting Trimagnetic Ensembles for Enhanced Magnetic Resonance Transverse Relaxivity.

An ensemble of nanosystems can be considered to improve magnetic resonance imaging (MRI) transverse relaxivity. Herein, an interacting superparamagnetic competing structure of an isotropic-anisotropic trimagnetic hybrid nanosystem, γ-Fe2O3@δ-MnO2@NiFe2O4, is considered for MRI relaxivity exploration. The interacting superparamagnetic system reveals fascinating dynamic magnetic behavior, where flower-shaped two-dimensional flakes are decorated over nanoparticles. The hybrid nanosystem exhibits modulated shape anisotropy with spin blocking and energy barrier broadening, which help in achieving faster MR transverse relaxivity. The hierarchical architecture ensemble of the trimagnetic landscape shows effective MR transverse relaxivity with a transverse (r2)/longitudinal (r1) relaxivity of 61.5 and potential cell viability. The competing trimagnetic system with regulated activation energy is found to be the underlying reason for such signal enhancement in MRI contrast efficiency. Hence, this study displays a novel pathway correlating MR transverse relaxivity with dynamic magnetic behavior and competing landscape of hierarchical trimagnetic ensembles.

Comprehensive polyphenolic profiling, antioxidant, antimicrobial, and cytotoxicity studies of Rhynchostylis retusa (L.) Blume: a medicinal orchid.

Rhynchostylis retusa (L.) Blume, commonly known as the Foxtail orchid, has garnered worldwide attention for its diverse medicinal properties. In this study, root extract and its fractions were evaluated for total polyphenols, flavonoids, targeted polyphenols, and antioxidant potential. The antimicrobial activity was assessed against Gram-positive and Gram-negative bacterial strains while cytotoxicity was assessed using the A549 and HCT-116 cell lines. The investigations showed that chloroform and ethyl acetate are the most effective solvents for fractionation of polyphenols from the parent extract. These fractions also exhibited strong antioxidant and cytotoxic potentials. The chloroform fraction showed maximum cell death of 87.35 and 92.36% in A549 and HCT- 116 cell lines respectively. All samples showed growth inhibition against bacterial strains except the n-hexane fraction, whereas the n-butanol fraction showed comparable antimicrobial activity with the tetracycline standard. The possible health benefits and thereby, application of R. retusa were thus revealed in this investigation.

Functionalized solid lipid nanoparticles combining docetaxel and erlotinib synergize the anticancer efficacy against triple-negative breast cancer.

The goal of the study was to fabricate folic acid functionalized docetaxel (DOC)/erlotinib (ERL)-loaded solid lipid nanoparticles (SLNs) to synergistically increase the anticancer activity against triple-negative breast cancer. DOC/ERL-SLNs were prepared by the high shear homogenization - ultrasound dispersion method (0.1 % w/v for DOC, and 0.3 %w/v for ERL) and optimized using Plackett Burman Design (PBD) followed by Box Behnken Design (BBD). The optimized SLNs demonstrated particle size < 200 nm, PDI < 0.35, and negative zeta potential with entrapment and loading efficiency of ∼80 and ∼4 %, respectively. The SLNs and folic acid functionalized SLNs (FA-SLNs) showed sustained release for both drugs, followed by Higuchi and Korsemeyer-Peppas drug release models, respectively. Further, the in vitro pH-stat lipolysis model demonstrated an approximately 3-fold increase in the bioaccessibility of drugs from SLNs compared to suspension. The TEM images revealed the spherical morphology of the SLNs. DOC/ERL loaded SLNs showed dose- and time-dependent cytotoxicity and exhibited a synergism at a molar ratio of 1:3 in TNBC with a combination index of 0.35 and 0.37, respectively. FA-DOC/ERL-SLNs showed enhanced anticancer activity as evidenced by MMP and ROS assay and further inhibited the colony-forming ability and the migration capacity of TNBC cells. Conclusively, the study has shown that SLNs are encouraging systems to improve the pharmaceutical attributes of poorly bioavailable drugs.

Clinical metabolomics investigation of rheumatoid arthritis patients receiving ayurvedic whole system intervention.

BACKGROUND: Arthritis is a common clinical condition seen in Ayurveda clinics. Clinical trials have reported Ayurvedic interventions to be of benefits in many arthritic conditions including Rheumatoid Arthritis (RA). No mechanistic details however are available about how such interventions on their own or as a combination of whole system Ayurveda might be working. OBJECTIVE: The study aims to evaluate simultaneously the clinical outcome of Ayurveda whole system (AWS) intervention in RA patients and identifying the serum metabolic signatures which could be useful for diagnosing the disease and monitoring treatment response. MATERIAL AND METHODS: RA patients (n = 37) simultaneously diagnosed as Amavata fulfilling the specific inclusion and exclusion criteria were recruited in the study and were given Ayurveda whole system (AWS) intervention comprised of oral medicines, local therapy and dietary recommendation for 3 months. The clinical and serum metabolic changes were investigated for pre-treatment RA patients (baseline RA group, n = 37) and post-treatment RA patients (following treatment of 6-weeks (RA_F, n = 26) and three months (RA_T, n = 36). For comparative serum metabolomics analysis, 57 normal healthy control (HC) subjects were also involved and the serum metabolic profiles were measured at high-field 800 MHz NMR spectrometer. The serum metabolic profiles were compared using multivariate statistical analysis and discriminatory metabolic features were evaluated for diagnostic potential using receiver operating characteristic (ROC) curve analysis. RESULTS: A significant reduction in DAS-28 ESR, AAM Score, total swollen joints, total tender joints were observed following AWS intervention. The clinical outcomes were concordant with changes in metabolic profiles of RA patients as these were also shifting towards the normal levels following the intervention. Compared to healthy control (HC) subjects, the sera of baseline RA patients were characterised by increased circulatory level of succinate, lysine, mannose, creatine, and 3-Hydroxybutyrate (3-HB) and decreased levels of alanine. The present study also evaluated the serum metabolic ratios for their discriminatory and diagnostic potential and notably, six metabolic ratios (KHR, KThR, KVR, GHR, PTR and SHR) were found significantly altered (elevated) in baseline RA patients. However, in RA patients receiving AWS treatment, these metabolic changes showed marked convergence towards the metabolic signatures of healthy controls. CONCLUSION: This first of its kind study clearly shows the clinical efficacy of Ayurvedic Whole System (AWS) intervention in the management of Rheumatoid Arthritis (RA), as demonstrated by significant improvements in key clinical parameters. The intervention not only alleviated symptoms but also induced a profound metabolic shifting towards normalization; thus, underscoring the potential of AWS intervention to modulate cellular metabolism in a manner that facilitates a return to homeostasis in RA patients. However, future studies are imperative to confirm these preliminary observations and delineate the underlying mechanisms of action of intervention in cases of RA.

Seroepidemiology of hepatitis B virus (HBV) and relationship to serum transaminase levels in Indian population.

Background: Hepatitis B virus (HBV) infection is a serious public health issue that must be addressed. Aim: The goal of this study was to investigate the correlation between serological status for hepatitis Be antigen (HBeAg)/anti-HBe, serum transaminase levels, and serum HBV-DNA in patients with chronic HBV infection. Methods: A retrospective observational study with 620 patients with persistent HBV infection (mean age, 36.35 years; 506 men) was conducted. All patients tested positive for hepatitis B surface antigen (HBsAg). Liver profile, HBeAg, and anti-HBe antibody tests were conducted for all patients. Additionally, serum HBV DNA was examined using a DNA assay in these individuals. Results: Of 620 patients, 114 (18.39%) were HBeAg-positive and 506 (81.61%) HBeAg-negative. A detectable level of HBV DNA was found in 89.79% of HBeAg-positive/anti-HBe negative patients compared to HBeAg-negative/anti-HBe positive carriers 33.69% (P value <0.0001). The median viral load was significantly higher in HBeAg-positive cases (4.72 log10 copies/mL) than in HBeAg-negative individuals (4.23 log10 copies/mL; P = 0.997). Additionally, a higher proportion of HBeAg-positive samples (P = 0.0001) had HBV-DNA levels above 10,000 copies/mL.

Combinatorial Delivery of Docetaxel- and Erlotinib-Loaded Functionalized Nanostructured Lipid Carriers for the Treatment of Triple-Negative Breast Cancer Using Quality-by-Design Approach.

This study explored the combined administration of docetaxel (DOC) and erlotinib (ERL) using nanostructured lipid carriers (NLCs), with folic acid (FA) conjugation to enhance their synergistic anticancer efficacy against triple-negative breast cancer. NLCs were developed through hot melt homogenization-ultrasound dispersion, and optimized by a quality-by-design (QbD) approach using Plackett-Burman design and Box-Behnken design. Plots were generated based on maximum desirability. Spherical, nanosized dispersions (<200 nm) with zeta potential ranging from -16.4 to -14.15 mV were observed. These nanoformulations demonstrated ~95% entrapment efficiency with around 5% drug loading. Stability tests revealed that the NLCs remained stable for 6 months under storage conditions at 4 °C. In vitro release studies indicated sustained release over 24 h, following Higuchi and Korsmeyer-Peppas models for NLCs and FA NLCs, respectively. Additionally, an in vitro pH-stat lipolysis model exhibited a nearly fivefold increase in bioaccessibility compared to drug-loaded suspensions. The DOC-ERL-loaded formulations exhibited dose- and time-dependent cytotoxicity, revealing synergism at a 1:3 molar ratio in MDA-MB-231 and 4T1 cells, with combination indices of 0.35 and 0.37, respectively. Co-treatment with DOC-ERL-loaded FA NLCs demonstrated synergistic anticancer effects in various in vitro assays.

Preclinical determination of wound-healing activity of halibut oil cream in rat model of burn wound.

This study investigated the effects of halibut oil cream, containing omega-3 fatty acids, vitamins A and D, and hydroxyproline, on burn wound healing in rats. Acute dermal toxicity tests confirmed its nontoxicity. Wistar rats were divided into five groups: a control, a positive control treated with silver sulfadiazine 1% (SSD), and three groups treated with 3%, 9%, and 27% halibut oil cream Formulation (HBOF). The SSD and HBOF groups showed significant healing improvements compared to the control. Histopathological analysis indicated increased collagen production in the HBOF groups, suggesting halibut oil cream's potential as a topical treatment for burn wounds.

Application of Casein Micelles for Targeting Huntington's Disease in Experimental Zebrafish Model.

Huntington's disease (HD) is an incorrigible neuropsychiatric disorder with reduced cognition and motor abnormalities. Piperine (PIP) is an alkaloid with antioxidant, anti-inflammatory, and neuroprotective activities; however, poor therapeutic efficacy limits its further use. The current study focuses on the enhanced therapeutic potential of PIP@CM against an experimental zebrafish model of HD. PIP@CM was fabricated using spray drying technology, followed by solid-state investigations. We performed in vitro release and in vitro antioxidant activity (DPPH assay) of PIP and PIP@CMs. In addition, in vivo studies were conducted on zebrafish using 3-nitropropionic acid (3-NPA) (60 mg/kg) as a neurotoxin and treated with PIP (5 mg/kg) and PIP@CM (25 mg/kg equivalent to 5 mg/kg PIP). After dosing, various in vivo studies (behavioral, biochemical, and histological) were conducted. The solid-state characterization techniques revealed the loss of crystallinity after micelles formation. In vitro release and antioxidant assays showed higher release and enhanced activity of PIP@CM. In vivo studies revealed that 3-NPA administration causes HD, as evidenced by the results of open field test (OFT) and novel tank diving test (NTD) tests. Moreover, 3-NPA causes an increase in oxidative stress, as confirmed by biochemical and histopathological studies. PIP@CM treatment significantly improved behavioral performance in OFT and NTD tests and reduced oxidative stress markers as compared to pure PIP and untreated HD model.

PI3Kγ in B cells promotes antibody responses and generation of antibody-secreting cells.

The differentiation of naive and memory B cells into antibody-secreting cells (ASCs) is a key feature of adaptive immunity. The requirement for phosphoinositide 3-kinase-delta (PI3Kδ) to support B cell biology has been investigated intensively; however, specific functions of the related phosphoinositide 3-kinase-gamma (PI3Kγ) complex in B lineage cells have not. In the present study, we report that PI3Kγ promotes robust antibody responses induced by T cell-dependent antigens. The inborn error of immunity caused by human deficiency in PI3Kγ results in broad humoral defects, prompting our investigation of roles for this kinase in antibody responses. Using mouse immunization models, we found that PI3Kγ functions cell intrinsically within activated B cells in a kinase activity-dependent manner to transduce signals required for the transcriptional program supporting differentiation of ASCs. Furthermore, ASC fate choice coincides with upregulation of PIK3CG expression and is impaired in the context of PI3Kγ disruption in naive B cells on in vitro CD40-/cytokine-driven activation, in memory B cells on toll-like receptor activation, or in human tonsillar organoids. Taken together, our study uncovers a fundamental role for PI3Kγ in supporting humoral immunity by integrating signals instructing commitment to the ASC fate.

Efficacy of platelet-rich fibrin in maxillary sinus augmentation and simultaneous implant placement in deficient maxillary ridges: A pilot comparative study.

Background: Rehabilitation with dental implants has become the most widely accepted treatment protocol for rehabilitation of lost natural teeth. Direct sinus lift is one of the most predictable procedures for augmenting the deficient posterior maxillary ridges. Methods: The study was designed in patients with insufficient bone for implants in the maxillary posterior ridges. The test group received platelet-rich fibrin alone as filler, and the control group received a bone allograft. The residual bone height (RBH), implant mobility, and soft tissue characteristics between and within the groups were compared and analyzed. Results: Both the groups had considerable gain in RBH, and the intragroup analysis revealed clinical gain in bone height in both the groups, with the test group exhibiting statistically significant gain which kept on improving from 6 months with z= -3.477 and a p value of 0.001 to 9 months with z=-3.531 and a p value of 0.027. Conclusion: The results suggest that the use of platelet-rich fibrin alone improves the bone regeneration, thereby achieving predictable and stable augmentation of the sinus floor required for the success of implant therapy.

Inhibit-AND logic gate enabled versatile BoF-AgNPs as ultrasensitive and selective nanoprobe for Mn(II) ions and nanocatalyst for rapid MB decoloration.

There is great interest in fabricating devices that can detect and remove water pollutants, especially heavy metal ions and dyes from wastewater, to promote sustainable water use. In this study, an extract of Borassus flabellifer leaves (BoF-LE) was used to synthesize silver nanoparticles (BoF-AgNPs), with the BoF-LE serving as a reducing and capping agent. The sensitivity and selectivity of BoF-AgNPs for Mn(II) ions were tested by comparing with the control sample and other competent metal ions. Our results showed that BoF-AgNPs are extremely sensitive and selective in detecting Mn(II) ions, with a detection limit of 0.3 ppb. HR-TEM, UV-Vis spectroscopy, and DLS investigations were used to confirm that BoF-AgNPs detect Mn(II) ions by an aggregation-based mechanism. Additionally, it was found that BoF-AgNPs are effective in rapidly decolorizing MB dye, as demonstrated by their ability to decolorize MB by 92.66% within 7 min. This study is the first to report successful synthesis of BoF-AgNPs and their two applications, which are enabled with an Inhibit-AND logic gate. Using BoF-AgNPs to detect and degrade water pollutants may promote sustainable water use.

Metal-free adsorption and photodegradation methods for methylene blue dye removal using different reduction grades of graphene oxide.

The release of organic pollutants and dyes into the environment by industries has had profound and harmful effects on both humans and ecosystems. Graphene oxide (GO) and its reduced form have been investigated for their effectiveness in removing pollutant dyes. GO nano-powder was synthesized using an improved version of Hummer's method and subsequently thermally reduced at various temperatures, including 125, 150, 175, and 200 °C, under vacuum conditions. In the X-ray diffraction spectra, an intense (001) diffraction peak was initially observed at 9.136° (2θ) for pristine GO. This peak gradually shifted towards higher angles as the reduction process took place and eventually disappeared when the GO was reduced at 200 °C. The intensity ratio of the D and G bands (ID/IG ratio) for GO nano-powder in the Raman spectra decreased from 0.94 to 0.76 due to the reduction process. The FTIR spectra of GO and reduced graphene oxide (rGO) also illustrated the reduction process. The bandgap of pristine GO significantly decreased from 2.31 to 0.73 eV, as determined by ultraviolet-visible (UV-Vis) diffuse reflectance spectrophotometry during the reduction process. The surface area and pore volume of both pristine GO and rGO-150 were determined using the BET (Brunauer-Emmett-Teller) and BJH (Barrett-Joyner-Halenda) methods. The results indicated an increase in the BET surface area from 6.61 to 7.86 m2/g and a corresponding enhancement in pore volume from 0.118 to 0.128 cc/g after reduction. The adsorption and photocatalytic degradation behavior of pristine GO and reduced graphene oxides (rGOs) were examined using methylene blue dye. The pristine GO demonstrated impressive adsorption capability, effectively removing the dye by 85.78 % within just 15 min and achieving nearly 97 % removal after 4 h. In contrast, the highest photocatalytic degradation of methylene blue, about 47.58 %, was attained for the rGO sample reduced at 150 °C under the illumination of visible light.

Sesame Genomic Web Resource (SesameGWR): a well-annotated data resource for transcriptomic signatures of abiotic and biotic stress responses in sesame (Sesamum indicum L.).

Sesame (Sesamum indicum L.) is a globally cultivated oilseed crop renowned for its historical significance and widespread growth in tropical and subtropical regions. With notable nutritional and medicinal attributes, sesame has shown promising effects in combating malnutrition cancer, diabetes, and other diseases like cardiovascular problems. However, sesame production faces significant challenges from environmental threats such as charcoal rot, drought, salinity, and waterlogging stress, resulting in economic losses for farmers. The scarcity of information on stress-resistance genes and pathways exacerbates these challenges. Despite its immense importance, there is currently no platform available to provide comprehensive information on sesame, which significantly hinders the mining of various stress-associated genes and the molecular breeding of sesame. To address this gap, here a free, web-accessible, and user-friendly genomic web resource (SesameGWR, http://backlin.cabgrid.res.in/sesameGWR/) has been developed This platform provides key insights into differentially expressed genes, transcription factors, miRNAs, and molecular markers like simple sequence repeats, single nucleotide polymorphisms, and insertions and deletions associated with both biotic and abiotic stresses.. The functional genomics information and annotations embedded in this web resource were predicted through RNA-seq data analysis. Considering the impact of climate change and the nutritional and medicinal importance of sesame, this study is of utmost importance in understanding stress responses. SesameGWR will serve as a valuable tool for developing climate-resilient sesame varieties, thereby enhancing the productivity of this ancient oilseed crop.

Assessment of radiosensitivity and enhancing key steviol glycosides in Stevia rebaudiana Bertoni through gamma radiation.

PURPOSE: Stevia rebaudiana Bertoni is a perennial herb, widely used as a natural sweetener around the globe. The key compounds responsible for its sweetness includes stevioside and rebaudioside-A. In order to improve these steviol glycosides, the present study was initiated to study the effect of induced mutagenesis on growth parameters, steviol glycosides and nuclear DNA content in Stevia rebaudiana Bertoni using ten doses of gamma-rays (5-100 kR). MATERIALS AND METHODS: Healthy seeds of 'Madhuguna' variety of Stevia rebaudiana Bertoni developed and maintained at stevia breeding farm, Agrotechnology division, CSIR-Institute of Himalayan Bioresource Technology, Palampur (HP), India were irradiated with ten doses of gamma rays (600 seeds each/dose) ranging from 5 kR to 100 kR (i.e., 5, 10, 15, 20, 30, 40, 50, 60, 80 and 100 kR) using Co60 gamma irradiation chamber at CCS Haryana Agricultural University, Hisar, (Haryana), India. RESULTS: Significant variations were recorded for all the seedling traits studied while major impact was noticed on the seedling after reaching the cotyledonary stage and doses above 40 kR showed absolute mortality of the seedlings. Based on probit analysis, the optimum LD50 dose lies in the range of 20-23 kR. Glycosidic profiling of 296 mutants using high-performance liquid chromatography showed decreased total steviol glycoside content with increased radiation dose. Doses 5 kR and 10 kR, were found to be effective in increasing the overall glycosidic content. A total of 72 promising mutants were also screened for increased rebaudioside-A stevioside ratio. Comparison of nuclear DNA content using flow cytometry revealed a similar decrease in the total nuclear DNA content with increase in dosage of gamma rays. The average genome size at 5, 10, 15, 20 and 30 kR treatments were 2.72, 2.69, 2.68, 2.70 and 2.66 pg as compared to 2.72 pg in control. CONCLUSIONS: Mild dose of gamma rays (5 and 10 kR) in stevia were found to be effective in improving the mean steviol glycoside content and may be used in future stevia mutation programmes.