Enhancement of Phenolic Compounds and Antioxidative Activities by the Combination of Culture Medium and Methyl Jasmonate Elicitation in Hairy Root Cultures of Lactuca indica L.

Abstract

Lactuca indica L. has been traditionally used as a wild vegetable and as a medicinal plant for centuries. The various compounds present in it and their biological activities have been extensively reported. Hairy-root culture combined with agrobacterium-meditated metabolic engineering is a useful technique to achieve stable production of biologically active plant compounds. Here, we evaluated the enhancement of secondary metabolites in L. indica L. and their bioactivities by testing culture media composition and the use of an elicitor. Hairy roots were induced and cultured in MS or SH liquid media for 2 weeks prior to treatment with various concentrations of MeJa, for different periods. The resulting phenolic contents and physiological activities were analyzed. Higher total phenolic, flavonoid, and hydroxycinnamic acids contents were attained by elicitation with MeJa. Metabolite accumulation, especially in SH media and in the presence of MeJa, was time dependent. Particularly, accumulation of chicoric acid increased markedly with time. Similarly, we observed time dependent positive and negative responses of antioxidant activity in DPPH and ABTS assays, respectively. As in previous studies, the highest correlation was found between total phenolic content and total flavonoid content. Further, 3,5-DCQA showed the highest correlation with total phenolic content, total flavonoid content, and antioxidant activities in hydroxycinnamic acids. Our data effectively identified optimal culture conditions to increase the accumulation of secondary metabolites and antioxidant activity in hairy roots cultures of L. indica L.

The Anti-Proliferative and Anti-Invasive Effect of Leaf Extracts of Blueberry Plants Treated with Methyl Jasmonate on Human Gastric Cancer In Vitro Is Related to Their Antioxidant Properties

“…Interestingly, Cocetta et al [50] detected an increased expression of phenylalanine ammonium lyase, chalcone synthase, and anthocyanidin synthase genes in blueberry plants, as well as increments of epicatechin and anthocyanin concentrations in plants of blueberry treated with MeJA. In lettuce, the pre-harvest exogenous application of methyl jasmonate (MeJA) increased total phenolic compound content and antioxidant capacity, which was attributed to a caffeic acid derivative and an unknown phenolic compound [27]. In the same way, Li et al [51] determined the optimal concentration of exogenous MeJA for the promotion of the sprouting in mung beans, showing that the application of this phytohormone resulted in improved antioxidant capacity and total polyphenols.…”

“…Several studies have shown that the healthy properties of fruit species can be affected by a series of factors such as genetic background, environmental conditions, cultural practices, and post-harvest handling. Earlier studies showed that both pre-and post-harvest applications of the volatile signal molecule methyl jasmonate (MeJA) induce the synthesis of phenolic compounds with antioxidant properties in berries [24][25][26][27], improving their potential advantageous impacts on human health.…”

Carrot Anthocyanins Genetics and Genomics: Status and Perspectives to Improve Its Application for the Food Colorant Industry

“…Indeed, foliar-applied ethephon, a precursor of ethylene (ET), enhances the content of anthocyanin and total phenolic compounds in Deep Purple carrot roots by about 25%, indicating that the production of anthocyanin can be increased even in black carrot varieties already containing a high level of anthocyanins [ 112 ]. In blueberries, apples and lettuce, the exogenous application of jasmonic acid (JA) increases the total phenolics content and antioxidant capacity [ 113 , 114 , 115 ]. In Arabidopsis , both abscisic acid (ABA) and JA promote the biosynthesis of anthocyanin in the presence of sucrose, while gibberellic acid (GA) and ET repress anthocyanin production [ 116 , 117 , 118 , 119 ].…”

Effect of Elicitation on Polyphenol and Carotenoid Metabolism in Butterhead Lettuce (Lactuca sativa var. capitata)

“…Nonetheless, with respect to sensory acceptance, butterhead lettuce has better acceptance than iceberg among consumers. Molecules such as methyl jasmonate (MJ), arachidonic acid (AA), salicylic acid (SA), and Harpin protein (HP) have been used as elicitors on recent investigations. ,− MJ used in romaine and butterhead lettuce increased polyphenol and carotenoid content . AA and SA used in butterhead lettuce incremented polyphenol and carotenoid content, as well as antioxidant activity; meanwhile, HP had a bigger effect on carotenoids in butterhead lettuce. , Recent research, carried out by our research group, in butterhead lettuce showed that the elicitation effect depended on several factors, among them are the time of application and type of elicitor, and that the main effect was observed on polyphenols and carotenoid concentration .…”