Impact of induced mutation-derived genetic variability, genotype and varieties for quantitative and qualitative traits in Mentha species.

PURPOSE: The genus Mentha spp. is an aromatic herb from the family 'Lamiaceae'. It is extensively predominant in temperate and sub-temperate regions of the world. The essential oil of this species is enriched with broad aroma constituents extensively utilized in food, beverages, flavor, cosmetics, perfumery, and pharmaceutical enterprises. With the global menthol market size estimated to be worth USD 765 million in 2022, India (accompanied by China and Brazil) is the world's primary manufacturer, consumer, and exporter of Mentha oil. Despite prominent global demand, the crucial bottleneck in mint cultivation is the need for more superior commercial cultivars. Predominant vegetative propagation mode with difficulties in manual emasculation, differential blooming times, sterile/sub-sterile hybrids, and low seed viability are the primary containment in creating genetic variability by classical breeding approaches. Therefore, genetic complications encountered in conventional breeding have led the breeders to apply mutation breeding as an alternative crop improvement approach in Mentha spp. These attempts at mutation breeding have produced some distinctive mutants as genetic pools for plant breeding programs, and some novel mutant mint cultivars have been made available for commercial cultivation. CONCLUSIONS: The prime strategy in mutation-based breeding has proven an adept means of encouraging the expression of recessive genes and producing new genetic variations. The present review comprises a significant contribution of mutation breeding approaches in the development of mutant mint species and its effects on physiological variation, photosynthetic pigment, essential oil content and composition, phytochemical-mediated defense response, pathogen resistivity, and differential expression of genes related to terpenoid biogenesis. Development and diversification have led to the release of varieties, namely Todd's Mitcham, Murray Mitcham, Pranjal, Tushar, and Kukrail in M. piperita L., Mukta, and Pratik in M. cardiaca Baker, Neera in M. spicata L., Kiran in M. citrata Ehrh., and Rose mint in M. arvensis L. that have revolutionized and uplifted mint cultivation leading to economic gain by the farmers and entrepreneurs.

Radio-frequency (RF) room temperature plasma treatment of sweet basil seeds (Ocimum basilicum L.) for germination potential enhancement by immaculation.

Ocimum basilicum L. is an antiviral and immunity boosting medicinal plant and culinary herb. Potential use of sweet basils in COVID 19 prevention and management is making its demand rise. This study is aimed at germination potential enhancement of sweet basil seeds. Reported study is evidenced with scientific data of radio-frequency cold plasma treatment using Ar + O2 feed gas. O. basilicum seeds, placed inside the rotating glass bottle, were directly exposed to RF (13.56 MHz) plasma produced in Ar + O2 feed gas. Seed treatment was done using RF source power (60 W, 150 W, 240 W), process pressure (0.2 mbar, 0.4 mbar, 0.6 mbar), and treatment time (5 min, 10 min, 15 min) at different combinations. Results show that, the most efficient treatment provide up to ∼89 % of the germination percentage which is an enhancement by 32.3 % from the control. SEM images revealed slight shrinkage in the seed size with eroded appearance over the seed. Enhancement of lipid peroxidation, show that oxidation of seed coat may propagate internally. Water imbibition analysis, of the treated seeds, was carried out for 2-12 hours. Further analysis of seed weight, on every one hour, after soaking shows enhanced water absorption capability except the treatment at 240 W, 0.6 mbar and 15 min. Plasma treatment enhanced carbohydrate content and protein content which is reported to be due to increased primary metabolism. Whereas, increased activity of secondary metabolism results in the enhancement of enzymatic (catalase) and non-enzymatic antioxidants (proline). Vital growth parameters, such as SVI I and SVI II, got amplified by 37 % and 133 % respectively after treatment. Ameliorative effects of plasma treatment are found highly significant with a positive and significant correlation value (p < 0.01) between germination percentages, SVI I, SVI II, carbohydrate, protein and proline show their interrelationship. Ar + O2 plasma treatment is found to bring forth significant changes in the O. basilicum seeds which eventually enhanced the germination potential and it could be a very promising technology for the medicinal crop.

In silico screening of therapeutic potentials from Strychnos nux-vomica against the dimeric main protease (Mpro) structure of SARS-CoV-2.

The novel coronavirus also referred to as SARS-CoV-2 causes COVID-19 and became global epidemic since its initial outbreak in Wuhan, China, in December 2019. Research efforts are still been endeavoured towards discovering/designing of potential drugs and vaccines against this virus. In the present studies, we have contributed to the development of a drug based on natural products to combat the newly emerged and life-threatening disease. The main protease (MPro) of SARS-CoV-2 is a homodimer and a key component involved in viral replication, and is considered as a prime target for anti-SARS-CoV-2 drug development. Literature survey revealed that the phytochemicals present in Strychnos nux-vomica possess several therapeutic activities. Initially, in the light of drug likeness laws, the ligand library of phytoconstituents was subjected to drug likeness analysis. The resulting compounds were taken to binding site-specific consensus-based molecular docking studies and the results were compared with the positive control drug, lopinavir, which is a main protease inhibitor. The top compounds were tested for ADME-Tox properties and antiviral activity. Further molecular dynamics simulations and MM-PBSA-based binding affinity estimation were carried out for top two lead compounds' complexes along with the apo form of main protease and positive control drug lopinavir complex, and the results were comparatively analysed. The results revealed that the two analogues of same scaffold, namely demethoxyguiaflavine and strychnoflavine, have potential against Mpro and can be validated through clinical studies.Communicated by Ramaswamy H. Sarma.

Effect of ozone application on the removal of pesticides from grapes and green bell peppers and changes in their nutraceutical quality.

The present study evaluates the efficacy of ozonated water for the removal of pesticide residues in grapes and green bell peppers. Fruit fortified with pesticides (azoxystrobin, chlorothalonil, chlorpyrifos, cypermethrin, hexaconazole and methyl parathion) were subjected to 15 and 30 min aqueous ozone treatment. GC analysis of ozonated fruits showed a 48.67% to 96.95% decrease in pesticide residues of different pesticides. Methyl paraoxon, a toxic degradation product of methyl parathion, was detected in the ozonated water sample. To assess the effect of ozonation on the nutraceutical quality of fruits, the concentrations of eleven polyphenols and ascorbic acid were analyzed. The individual polyphenols showed different trend in 15 and 30 min treatment. Overall, there was an increase in the levels of all the polyphenols in grapes after 30 min ozonation treatment. In peppers, there was a net increase in quercetin, quercetin-3-O-glucoside, rutin and kaempferol in 30 min while other polyphenols were decreased. The ascorbic acid content of both the fruits was decreased by more than 70% upon ozonation. Thus, ozonation treatment was effective in pesticide removal. However, it changed the nutraceutical quality of grapes and green bell peppers.

Gamma irradiation-induced variability in morpho-agronomic and oil quality traits of Mentha piperita L.

PURPOSE: To develop elite mutant in Mentha piperita having morphotype and oil content of Mentha arvensis, and oil quality of M. piperita. MATERIALS AND METHODS: The dormant runner of menthol rich genotype MPK-5 were subjected to different doses of γ- irradiation (10, 20, 30, 50, 70, 90, and 110 Gy) at a dose rate of 55 Gy/min to induce the genetic variability for herb and oil yield as well as oil quality. A wide spectrum of variability for agro-morphological traits, herb yield, and quality profile was observed among the mutants. RESULTS: The developed and selected superior mutants viz. MPK-5(1) and MPK-5(3) have a mean herb yield potential of 23.923 and 21.503 Kg/9 m2; mean oil yield of 92.953 and 80.047 ml/plot; mean menthol content of 69.012% and 69.160% with mean menthofuran content of 1.554% and 0.531%, respectively. CONCLUSIONS: Mutational breeding through γ- irradiation is considered complementary to the conventional breeding method, to broaden the spectrum of genetic variability. The developed and selected mutants namely viz. MPK-5(1) and MPK-5(3) identified as promising mutants, based on herb yield, oil yield, and essential oil quality, could be used as a parental line for exploitation in hybridization program/recombinant breeding.

Ultra performance liquid chromatography coupled with principal component and cluster analysis of Swertia chirayita for adulteration check.

This article describes the study to standardize phytochemically and distinguish Swertia chirayita from that of possible substitution/adulteration using ultra performance liquid chromatography (UPLC) with photodiode array detector (PDA) and chemometric tools viz. principal component analysis (PCA) and hierarchical clustering analysis (HCA). Five ecotypes of Swertia chirayita and five possible substitutions, e.g.,Swertia bimaculata (SB), Swertia chordata (SCH), Swertia ciliata (SCL), Swertia paniculata (SP), and Halenia elliptica (HE) collected from different Indian Himalayan region. Samples evaluated for 04 marker compounds- swertiamarin (SM), mangiferin (MF), gentiopicroside (GP), and sweroside (SW). Reverse phase column (Waters Acquity BEH C18, 50 mm × 2.1 mm , 1.7 µm) provided high resolution for all target analytes with binary gradient elution. The detector response was linear (concentration 2.5-125 µg/mL, R2 > 0.999). The limit of detection (LOD) and quantification (LOQ) of targeted compounds was in the range of 1.40-2.06 and 4.57-6.27 µg/mL respectively. The combined relative standard deviation (%RSD) for intra-day and inter-day precision values were less than 2%. The recoveries study comply the method suitability. Chromatogram similarity analysis based on congruence coefficient was higher than 0.925 for the chirayita ecotypes while much lower than 0.629 for possible substitutes. HCA showed that the samples could be clustered (all 5 clusters in two-level) reasonably into different ecotypes and substitutes. HCA together with loading plots has indicated different chemical properties of all five groups. PCA results showed that the discrimination of chirayita ecotypes is because of the presence of SW while SM may have more influence on the targeted substitutes to discriminate from chirayita ecotypes. Therefore, UPLC fingerprint in association with chemometric tools provides a reliable and accurate quality assessment and detection of possible adulteration.

Synthesis, antifungal activity and structure-activity relationships of vanillin oxime-N-O-alkanoates.

Vanillin oxime-N-O-alkanoates were synthesized following reaction of vanillin with hydroxylamine hydrochloride, followed by reaction of the resultant oxime with acyl chlorides. The structures of the compounds were confirmed by IR, 1H, 13C NMR and mass spectral data. The test compounds were evaluated for their in vitro antifungal activity against three phytopathogenic fungi Macrophomina phaseolina, Rhizoctonia solani and Sclerotium rolfsii by the poisoned food technique. The moderate antifungal activity of vanillin was slightly increased following its conversion to vanillin oxime, but significantly increased after conversion of the oxime to oxime-N-O-alkanoates. While vanillin oxime-N-O-dodecanoate with an EC50 value 73.1 microg/mL was most active against M. phaseolina, vanillin oxime-N-O-nonanoate with EC50 of value 66.7 microg/mL was most active against R. solani. The activity increased with increases in the acyl chain length and was maximal with an acyl chain length of nine carbons.