Development of HPTLC method for determination of α-terpinyl acetate, and evaluation of antioxidant properties of essential oils in Elettaria cardamomum

Purpose: To develop a simple and reliable protocol for high performance thin layer chromatography (HPTLC) quantification of α-terpinyl acetate in oils extracted from Elettaria cardamomum, and to study relative antioxidant potential of oils obtained from three varieties of fruits of E. cardamomum. Methods: Essential oil was extracted separately from the fruits of three varieties of E. cardamomum, viz, Valley-green, Palakuzhi, and ICRI-2, using hydro-distillation method. In the development of an HPTLC method, standard α-terpinyl acetate was subjected to chromatography on aluminium-backed silica gel 60 F254 plates using a mobile phase of n-hexane: ethyl acetate (8:2, v/v), and quantified at 665 nm through densitometric analysis. The antioxidant property of essential oil of each cultivar was determined with respect to 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2'-azino-bis(3- ethylbenzothiazoline-6-sulphonic acid (ABTS) radical scavenging assays, as well as ferric reducing assay. Results: The developed HPTLC method showed a good resolution for α-terpinyl acetate, with Rf of 0.64 ± 0.01, and also showed good linearity of the calibration plots (r2 = 0.9982). The HPTLC method was validated as per ICH guidelines, and used for the determination of α-terpinyl acetate in the essential oils. The valley green variety of E. cardamomum had the highest content of α-terpinyl acetate (55.36 ± 1.33 %w/w). The inhibitory capacity (IC50 value) for the oil of valley green variety as determined using DPPH and ABTS methods was 378.2 and 19.87 μg/mL, respectively. Conclusion: The proposed HPTLC method is suitable for routine analysis of α-terpinyl acetate in medicinal herbs, and it reveals the role of α-terpinyl acetate in the antioxidant efficacy of cardamom oil

In vitro alteration of artemisinin biosynthesis in Artemisia annua L during treatment with methyl jasmonate

Purpose: To investigate the in vitro effect of methyl jasmonate (MeJA) on artemisinin biosynthesis in Artemisia annua.Method: The effect of two concentrations of MeJA i.e. 2 μm (T2) and 5 μm (T5) on biomass, plant height and artemisinin content of Artemisia annua L. was investigated in vitro in MS medium.Results: Plant height (6.5 ± 1.8 cm), biomass (0.18 ± 0.02 g/plant) and artemisinin content (0.035 ± 0.002 % dry weight) were higher in T5 and T2 treatment groups than in non-treated control plants (C). Artemisinin content, biomass and plant height were positively correlated after 2 - 8 days of treatment, but remained unchanged on the 12th day of treatment.Conclusion: The observed effects of exogenous MeJA on the biosynthesis of artemisinin and other secondary metabolites may lead to elucidation of promising targets for further studies on metabolic engineering of Artemisia annua L. Keywords: Artemisia annua L. Methyl jasmonate, HPLC, Artemisini

Perspective of Melatonin-Mediated Stress Resilience and Cu Remediation Efficiency of Brassica juncea in Cu-Contaminated Soils

The present study evaluated the influence of melatonin (MEL) on copper toxicity in terms of morphophysiological, microscopic, histochemical, and stress resilience responses in Brassica juncea. Different levels of Cu (0, 30, and 60 mg kg–1) were given in air-dried soil, and 25 days after sowing (DAS), plants were sprayed with 30, 40, or 50 μM of MEL. The results demonstrated that under Cu stress, a significant amount of Cu accumulated in plant tissues, particularly in roots than in upper ground tissues, thereby suppressing the overall growth as evidenced by decrease in tolerance index and photosynthesis and increase in oxidative stress biomarkers (reactive oxygen species, malondialdehyde, and electrolyte leakage content) and cell death. Interestingly, the follow-up treatment of MEL, mainly 40 μM, efficiently improved the physio-biochemical and growth parameters, sugar accumulation, and metabolism. The potential of MEL in modulating Cu stress is attributed to its involvement in enriching the level of nutrient and improving chloroplast and stomatal organization besides lowering oxidative stress via enhanced levels of antioxidants. MEL improved the Cu reclamation potential in plants by enhancing Cu uptake and its translocation to aerial tissues. Principal component analysis showed that most of the morphophysiological and growth attributes were positively linked with MEL and negatively related to Cu levels, whereas all the stress-enhancing attributes showed a strong relationship with excessive Cu levels in soils. The present study suggested that MEL has the potential to improve growth and photosynthesis resulting in improved stress resilience under Cu stress along with increased remediation capability of mustard for remediation of Cu-contaminated soils

Accumulation of chromium in plants and its repercussion in animals and humans

The untreated effluents released from industrial operations have adverse impacts on human health, environment and socio-economic aspects. Environmental pollution due to chromium is adversely affecting our natural resources and ecosystem. Chromium is hazardous carcinogenic element released from spontaneous activities and industrial procedures. Chromium toxicity, mobility and bioavailability depend mainly on its speciation. Chromium mainly exists in two forms, first as an immobile, less soluble trivalent chromium [Cr(III)] species under reducing conditions whereas hexavalent chromium [Cr(VI)] as a mobile, toxic and bioavailable species under oxidizing conditions. Hexavalent chromium is more pernicious in comparison to trivalent form. Chromium negatively affects crop growth, total yield and grain quality. Exposure of chromium even at low concentration enhances its accretion in cells of human-beings and animals which may show detrimental health effects. Many techniques have been utilized for the elimination of chromium. The selection of the green and cost-efficient technology for treatment of industrial effluent is an arduous task. The present review highlights the problems associated with chromium pollution and need of its immediate elimination by suitable remediation strategies. Further, investigations are required to fill the gaps to overcome the problem of chromium contamination and implementation of sustainable remediation strategies with their real-time applicability on the contaminated sites

SIMULTANEOUS EXTRACTION AND RAPID HPLC BASED QUANTIFICATION OF CROCIN AND SAFRANAL IN SAFFRON (CROCUS SATIVUS L.)

Objective: Saffron (Crocus sativus L.) is one of the most valuable crops with high medicinal values used in many diseases. The aim of the study was to establish the reliability and rapid HPLC method for analysis of crocin and safranal concentration present in stigmata of saffron in the market as well as field grown samples.Methods: Field grown and market stigmata of saffron were used for extraction of crocin and safranal. The linear dynamic ranges were established after validating the robustness of critical method parameters. The Agilent1260-Infinity Quaternary LC system was used for the preparation of calibration standards and quantification of crocin and safranal in C. sativus stigmata.Results: A good linearity was achieved in the range of 10-30 µg for each compound with the determination coefficient (R2). The calibration curves revealed linear regression (r. 0.997) for this rapid HPLC method and limit of quantifications (LOQs) were achieved in the range of 3.4 µg/ml for crocin and 10.2 µg/ml for safranal. The limit of detection (LODs) for all standards was ≤4.2 µg/ml. The range of crocin content (10.43-16.32 mg/g) and safranal (5.19-5.21 mg/g) was estimated in saffron samples.Conclusion: This method may serve the purpose of accurate quantification of crocin and safranal present in the stigmata of the plant in a quick time period.Keywords: Saffron, Crocin, Safranal, Extraction, Quantification, HPL

Identification and Comprehensive Genome-Wide Analysis of Glutathione S-Transferase Gene Family in Sweet Cherry (Prunus avium) and Their Expression Profiling Reveals a Likely Role in Anthocyanin Accumulation

Glutathione S-transferases (GSTs) in plants are multipurpose enzymes that are involved in growth and development and anthocyanins transportation. However, members of the GST gene family were not identified in sweet cherry (Prunus avium). To identify the GST genes in sweet cherry, a genome-wide analysis was conducted. In this study, we identified 67 GST genes in P. avium genome and nomenclature according to chromosomal distribution. Phylogenetic tree analysis revealed that PavGST genes were classified into seven chief subfamily: TCHQD, Theta, Phi, Zeta, Lambda, DHAR, and Tau. The majority of the PavGST genes had a relatively well-maintained exon–intron and motif arrangement within the same group, according to gene structure and motif analyses. Gene structure (introns-exons) and conserved motif analysis revealed that the majority of the PavGST genes showed a relatively well-maintained motif and exons–introns configuration within the same group. The chromosomal localization, GO enrichment annotation, subcellular localization, syntenic relationship, Ka/Ks analysis, and molecular characteristics were accomplished using various bioinformatics tools. Mode of gene duplication showed that dispersed duplication might play a key role in the expansion of PavGST gene family. Promoter regions of PavGST genes contain numerous cis-regulatory components, which are involved in multiple stress responses, such as abiotic stress and phytohormones responsive factors. Furthermore, the expression profile of sweet cherry PavGSTs showed significant results under LED treatment. Our findings provide the groundwork for future research into induced LED anthocyanin and antioxidants deposition in sweet cherries

In vitro inhibition of biofilm and virulence factor production in azole-resistant strains of Candida albicans isolated from diabetic foot by Artemisia vulgaris stabilized tin (IV) oxide nanoparticles

The advent of nanotechnology has been instrumental in the development of new drugs with novel targets. Recently, metallic nanoparticles have emerged as potential candidates to combat the threat of drug-resistant infections. Diabetic foot ulcers (DFUs) are one of the dreadful complications of diabetes mellitus due to the colonization of numerous drug-resistant pathogenic microbes leading to biofilm formation. Biofilms are difficult to treat due to limited penetration and non-specificity of drugs. Therefore, in the current investigation, SnO2 nanoparticles were biosynthesized using Artemisia vulgaris (AvTO-NPs) as a stabilizing agent and were characterized using ultraviolet–visible (UV–vis) spectroscopy, Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy-dispersive X-ray spectroscopy (EDX). Furthermore, the efficacy of AvTO-NPs against biofilms and virulence factors of drug-resistant Candida albicans strains isolated from DFUs was assessed. AvTO-NPs displayed minimum inhibitory concentrations (MICs) ranging from 1 mg/mL to 2 mg/mL against four strains of C. albicans. AvTO-NPs significantly inhibited biofilm formation by 54.8%–87%, germ tube formation by 72%–90%, cell surface hydrophobicity by 68.2%–82.8%, and exopolysaccharide (EPS) production by 69%–86.3% in the test strains at respective 1/2xMIC. Biosynthesized NPs were effective in disrupting established mature biofilms of test strains significantly. Elevated levels of reactive oxygen species (ROS) generation in the AvTO-NPs-treated C. albicans could be the possible cause of cell death leading to biofilm inhibition. The useful insights of the present study could be exploited in the current line of treatment to mitigate the threat of biofilm-related persistent DFUs and expedite wound healing

24-Epibrassinolide (EBR) Confers Tolerance against NaCl Stress in Soybean Plants by Up-Regulating Antioxidant System, Ascorbate-Glutathione Cycle, and Glyoxalase System

The present research was performed to assess the effect of 24-epibrassinolide (EBR) on salt-stressed soybean plants. Salt stress suppressed growth, biomass yield, gas exchange parameters, pigment content, and chlorophyll fluorescence, but all these parameters were up-regulated by EBR supply. Moreover, salt stress increased hydrogen peroxide, malondialdehyde, and electrolyte leakage. EBR supplementation reduced the accumulation of oxidative stress biomarkers. The activities of superoxide dismutase and catalase, and the accumulation of proline, glycinebetaine, total phenols, and total flavonoids increased with NaCl stress, but these attributes further increased with EBR supplementation. The activities of enzymes and the levels of non-enzymatic antioxidants involved in the Asc-Glu cycle also increased with NaCl stress, and further enhancement in these attributes was recorded by EBR supplementation. Salinity elevated the methylglyoxal content, but it was decreased by the EBR supplementation accompanying with up-regulation of the glyoxalase cycle (GlyI and GlyII). Salinity enhanced the Na+ uptake in root and shoot coupled with a decrease in uptake of Ca2+, K+, and P. However, EBR supplementation declined Na+ accumulation and promoted the uptake of the aforementioned nutrients. Overall, EBR supplementation regulated the salt tolerance mechanism in soybean plants by modulating osmolytes, activities of key enzymes, and the levels of non-enzymatic antioxidants

Insights into cucumber (Cucumis sativus) genetics: Genome-wide discovery and computational analysis of the Calreticulin Domain-Encoding gene (CDEG) family

Cucumber is an essential vegetable crop throughout the world. Cucumber development is vital for accomplishing both quality and productivity requirements. Meanwhile, numerous factors have resulted in substantial cucumber losses. However, the calreticulin domain-encoding genes (CDEGs) in cucumber were not well-characterized and had little function. In the genome-wide association study (GWAS), we recognized and characterized the CDEGs in Cucumis sativus (cucumber). Through a comprehensive study of C. sativus, our research has unveiled the presence of three unique genes, denoted as CsCRTb, CsCRT3, and CsCNX1, unevenly distributed on three chromosomes in the genome of C. sativus. In accordance to the phylogenetic investigation, these genes may be categorized into three subfamilies. Based on the resemblance with AtCDE genes, we reorganized the all CsCDE genes in accordance with international nomenclature. The expression analysis and cis-acting components revealed that each of CsCDE gene promoter region enclosed number of cis-elements connected with hormone and stress response. According to subcellular localization studies demonstrated that, they were found in deferent locations of the cell such as endoplasmic reticulum, plasma membrane, golgi apparatus, and vacuole, according to subcellular localization studies. Chromosomal distribution analysis and synteny analysis demonstrated the probability of segmental or tandem duplications within the cucumber CDEG gene family. Additionally, miRNAs displayed diverse modes of action, including mRNA cleavage and translational inhibition. We used the RNA seq data to analyze the expression of CDEG genes in response to cold stress and also improved cold tolerance, which was brought on by treating cucumber plants to an exogenous chitosan oligosaccharide spray. Our investigation revealed that these genes responded to this stress in a variety of ways, demonstrating that they may adapt quickly to environmental changes in cucumber plants. This study provides a base for further understanding in reference to CDE gene family and reveals that genes play significant functions in cucumber stress responses

COMPARATIVE STUDY OF METABOLITES AND ANTIMICROBIAL ACTIVITIES OF ESSENTIAL OILS EXTRACTED FROM THREE AMOMUM SUBULATUM CULTIVARS: Isolation, chemical characterization, antimicrobial study of three Greater cardamom cultivars essential oils

Objective: In Sikkim (India), Seremna is a highly growing cultivar of Amomum subulatum at lower altitudes. Other popular cultivated varieties are Varlangy and Sawney in the same state but at different altitude. In this study, we evaluate the variation in essential oils, metabolites and antimicrobial activities among A. subulatum selected cultivars. Methods: The composition of essential oil of Varlangy, Seremna, and Sawney was analyzed using gas chromatography–mass spectrometry and comparative antimicrobial activity of oils was explored using agar well diffusion and agar dilution method. Results: The Seremna cultivar oil was shown the high content of major constituents (1,8-cineole) in comparison to others. Comparative minimum inhibitory concentrations and minimal bactericidal concentration (MBC) or minimal fungicidal concentration against two Gram-positive (Staphylococcus aureus and Bacillus subtilis), two Gram-negative (Klebsiella pneumoniae and Escherichia coli) bacteria, and two (Candida albicans and Aspergillus niger) fungi were determined. The oil of Seremna showed distinct antibacterial and antifungal activity against all the microorganisms except B. subtilis which showed resistance. Conclusion: The present findings concluded that the high content of the principal compound accelerates the antimicrobial activity of essential oils. The essential oil of Seremna could be a good antimicrobial agent and recommended in the case of infections