Variability in Catechin and Rutin Contents and Their Antioxidant Potential in Diverse Apple Genotypes.

Catechins and rutin are among the main metabolites found in apple fruit. Sixty apple genotypes, harvested in 2016 and 2017, were analyzed for their phenolic content and antioxidant activity. The HPLC analysis showed that the catechin concentration ranged from 109.98 to 5290.47 µg/g, and the rutin concentration ranged from 12.136 to 483.89 µg/g of apple fruit. The level of DPPH activity ranged from 9.04% to 77.57%, and almost half of the 15 genotypes showed below 30⁻40% DPPH activity. The apple genotypes 'Lal Ambri', 'Green Sleeves', and 'Mallus floribunda' showed the highest DPPH activity of between 70% and 80%, while 'Schlomit', 'Luxtons Fortune', 'Mayaan', 'Ananas Retrine', and 'Chaubatia ambrose' showed the lowest ferric reducing antioxidant power (FRAP) activity (0.02⁻0.09%). Statistical analysis showed a correlation between DPPH activity and catechin content (r = 0.7348) and rutin content (r = 0.1442). Regarding antioxidant activity, fractionated samples of apple genotypes revealed significant activity comparable to that of ascorbic acid. There was also a consistent trend for FRAP activity among all apple genotypes and a significant positive correlation between FRAP activity and rutin content (r = 0.244). Thus, this study reveals a significant variation in antioxidant potential among apple genotypes. This data could be useful for the development of new apple varieties with added phytochemicals by conventional and modern breeders.

Effect of environmental variables on phytonutrients of Origanum vulgare L. in the sub-humid region of the northwestern Himalayas.

Ecological and soil physiochemical parameters impact the crop quality and development. In spite of the huge commercial prospective, the phytonutrient and chemometric profiles of Himalayan oregano (Origanum vulgare L.) have not been evaluated, and their relationships with ecological parameters are still lacking. The objective of this research study was to evaluate the disparity in the phytonutrient profiles of different ecotypes of O. vulgare in wild and cultivated populations and determine whether such variation was related to the diverse climatic and edaphic conditions prevailing in the northwestern Himalayas. Micrometeorological, atomic absorption spectroscopy for micro-elemental analysis was determined for soil. HPLC was used to determine the disparity in phytonutrient (quercetin, betacarotene, ascorbic acid, and catechin) and phytochemical (arbutin) levels. Cultivated populations had lower phytonutrient levels than wild populations. The habitat exhibiting pH values ranging from 6 to 7 elevated organic carbon (2.42%), nitrogen (97.41 kg ha-1), and manganese (10-12 µg g-1) and zinc contents (0.39-0.50%) show luxirant growth of Origanum vulgarel. The phytonutrient (quercetin, betacarotene, ascorbic acid, arbutin, and catechin) levels had a direct relationship with UV-B flux (r2 = 0.82) and potassium (r2 = 0.97). Wild accessions predominantly contained catechin and ascorbic acid, with maximum values of 163.8 and 46.88 µg g-1, respectively, while the cultivated accessions had the highest level of arbutin (53.42 µg g-1). Maximum variation was observed in quercetin (114.61%) followed by ß-carotene (87.53%). Cultivated accessions had less quercetin (0.04-1.25 µg g-1) than wild accessions (1.25-2.87 µg g-1). Wild accessions had higher phytonutrient values for catechin, ß-carotene, and ascorbic acid while cultivated accessions had maximum values for arbutin. The correlation of environmental variables with phytonutrient levels paves the way for metabolomic-guided enhancement of agricultural practices for better herb quality.

Plummeting anthropogenic environmental degradation by amending nutrient-N input method in saffron growing soils of north-west Himalayas.

Nitrous-oxide emission and nitrate addition from agriculture to earth's environment are two main agriculture related anthropogenic causes of environmental degradation that needs greater attention. For addressing the aforesaid issue, new techniques/practices need to be developed and implemented. The present investigation, which was focused on this issue, resulted in developing a new mode of nitrogen (N) placement, i.e. 'mid rib placement upper to corms in two splits (MRPU-2S)', that could reduce nitrous oxide N emission by around 70.11% and, nitrate N leaching and runoff by around 68.26 and 67.09%, respectively, over conventional method, in saffron growing soils of northwest Himalayas. Besides plummeting environmental degradation, MRPU-2S further resulted in enhancing saffron yield by 33.33% over conventional method. The findings of the present investigation were used to develop new empirical models for predicting saffron yield, nitrate N leaching and nitrous-oxide N emission. The threshold limits of nitrate N leaching and nitrous oxide N emission have also been reported exclusively in the present study.