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A greenhouse pot experiment was conducted to evaluate the impact of zinc supply (0, 1, and 2 mM Zn as ZnSO4) on morpho-physiological and biochemical parameters of caraway (Carum carvi L.). Exposure to different Zn concentrations for 12 weeks compromised severely all growth parameters (plant height, number of secondary branches, diameter of primary and secondary branches, fresh and dry weight of aerial parts and roots) yield and its components (number of umbels per primary branches and secondary branches; number of umbel per plant; number of seeds per plant; and the weight of 1000 seeds). These manifestations were intimately linked with excessive accumulation of Zn in roots and leaves, alteration of the content of photosynthetic pigments, and extended lipid peroxidation. A manifest increment of proline and soluble sugar content was also observed in response to Zn application. Lipid content in seeds was dropped in Zn-treated plants and the fatty acid profiles were profoundly affected as they were enriched with saturated fatty acids at the expense of unsaturated ones. While improving their oxidative stability as revealed by the reduced values calculated oxidizability and oxidative susceptibility, Zn treatment reduced the lipid nutritional quality of caraway seeds. Moreover, Zn treatment reduced the essential oil yield and its main component carvone while it enhanced the content of its precursor limonene. It also induced alteration of terpene metabolism as revealed in the redirection of the carbon flux to the shikimate/phenylpropanoid pathway resulting in the stimulation of the production of phenolic compounds and their subsequent antioxidant activities. [ABSTRACT FROM AUTHOR]

Enzyme-assisted extraction has emerged as an attractive green, cost-effective and high bioactive yielding technology by which desired bioactives with preserved or better efficacy are released. In the present study, the ability of cellulase, hemicellulase and their binary mixture (cellulase:hemicellulase; 1:1) in improving the extraction of essential oils from coriander (Coriandrum sativum L.) seeds, or the residue by-products from the distillation process containing value-added phytochemicals (fatty acids and phenolics) were evaluated. Cellulase and the binary mixture improved the extraction of essential oils by 44.2 and 40%, respectively. Application of enzymes was associated with increased amount of oxygenated terpenes in the essential oils derived from enzyme-treated samples. Linalool, camphor and geranyl acetate were the prominent compounds. From the hydrodistillation residues, a better recovery of petroselinic-rich oil with a good nutritional quality was also observed in enzyme-treated seeds. They also contained an appreciable amount of polyphenols and showed an improved antioxidant activity as revealed by the DPPH, FRAP and cellular antioxidant activity assays. The results suggested that enzyme pre-treatment allowed better recovery without alteration of the essential oil composition. The hydrodistillation residues obtained could be potentially exploited for the development of functional food ingredients and nutraceuticals. [ABSTRACT FROM AUTHOR]