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Secondary metabolites have been shown to possess a range of biological functions. Flavonoids, due to their ability to scavenge ROS, are famous antioxidants. The plants of Artemisia species are rich sources of flavonoids; however, the amount of these metabolites is less. In the current study, the flavonoid content was detected and then enhanced by genetically modifying the Artemisia carvifolia Buch with Agrobacterium tumefaciens strain GV3101 carrying rol A gene. The transformation of rol A gene was confirmed with PCR and the gene copy number was confirmed by Southern blot analysis. The HPLC analysis revealed the presence of catechin (3.19 ug/mg DW) and geutisic acid (2.22 ug/mg DW) in transformed plants, unlike wild-type plants. In transformed plants, all detected flavonoids (vanillic acid, rutin, catechine, gallic acid, syringic acid, caffeic acid, coumaric acid, geutisic acid, ferulic acid, and cinnamic acid) were increased up to several folds. Real-time qPCR revealed the higher expression levels of the genes for flavonoid biosynthesis enzymes phenylalanine ammonia-lyase (PAL) and chalcone synthase (CHS) in plants transformed with rol A genes, as the expression levels were increased up to 9–20-fold and 2–6-fold, respectively. The rol A transgenic lines T3 and T5 carrying two copies of rol A gene, particularly showed higher expression of both PAL and CHS gene, with the highest expression in T3 line. The transgenic lines demonstrated an average increase of 1.4-fold in the total phenolic content and 1–2-fold in the total flavonoid content as compared to wild-type plants. Total antioxidant capacity and total reducing power were increased up to an average of 1–2-fold and 1.5–2-fold respectively, along with increased free radical scavenging ability. Furthermore, the rol A gene transgenics were found to have much greater cytotoxic capacity than the A. carvifolia wild-type plant against the MCF7, HeLA, and HePG2 cancer cell lines. Current findings show that the rol A gene effectively increases the flavonoid content of A. carvifolia Buch, boosting the plant's capacity as an antioxidant and an anticancer. This is the first-ever report, demonstrating the genetic transformation of Artemisia carvifolia Buch with rol A gene. [ABSTRACT FROM AUTHOR]

Secondary metabolites have been shown to possess a range of biological functions. Flavonoids, due to their ability to scavenge ROS, are famous antioxidants. The plants of Artemisia species are rich sources of flavonoids; however, the amount of these metabolites is less. In the current study, the flavonoid content was detected and then enhanced by genetically modifying the Artemisia carvifolia Buch with Agrobacterium tumefaciens strain GV3101 carrying rol A gene. The transformation of rol A gene was confirmed with PCR and the gene copy number was confirmed by Southern blot analysis. The HPLC analysis revealed the presence of catechin (3.19 ug/mg DW) and geutisic acid (2.22 ug/mg DW) in transformed plants, unlike wild-type plants. In transformed plants, all detected flavonoids (vanillic acid, rutin, catechine, gallic acid, syringic acid, caffeic acid, coumaric acid, geutisic acid, ferulic acid, and cinnamic acid) were increased up to several folds. Real-time qPCR revealed the higher expression levels of the genes for flavonoid biosynthesis enzymes phenylalanine ammonia-lyase (PAL) and chalcone synthase (CHS) in plants transformed with rol A genes, as the expression levels were increased up to 9–20-fold and 2–6-fold, respectively. The rol A transgenic lines T3 and T5 carrying two copies of rol A gene, particularly showed higher expression of both PAL and CHS gene, with the highest expression in T3 line. The transgenic lines demonstrated an average increase of 1.4-fold in the total phenolic content and 1–2-fold in the total flavonoid content as compared to wild-type plants. Total antioxidant capacity and total reducing power were increased up to an average of 1–2-fold and 1.5–2-fold respectively, along with increased free radical scavenging ability. Furthermore, the rol A gene transgenics were found to have much greater cytotoxic capacity than the A. carvifolia wild-type plant against the MCF7, HeLA, and HePG2 cancer cell lines. Current findings show that the rol A gene effectively increases the flavonoid content of A. carvifolia Buch, boosting the plant’s capacity as an antioxidant and an anticancer. This is the first-ever report, demonstrating the genetic transformation of Artemisia carvifolia Buch with rol A gene.

Background: The secondary metabolites of the Artemisia genus are well known for their important therapeutic properties. This genus is one of the valuable sources of flavonoids and other polyphenols, but due to the low contents of these important metabolites, there is a need to either enhance their concentration in the original plant or seek alternative sources for them. The aim of the current study was to detect and enhance the yield of antioxidant compounds of Artemisia carvifolia Buch. HPLC analysis was performed to detect the antioxidants. With the aim of increasing flavonoid content, Rol gene transgenics of A. carvifolia were established. Two genes of the flavonoid biosynthetic pathway, phenylalanine ammonia-lyase and chalcone synthase, were studied by real time qPCR. Antioxidant potential was determined by performing different antioxidant assays. Results: HPLC analysis of wild-type A. carvifolia revealed the presence of flavonoids such as caffeic acid (30 μg/g DW), quercetin (10 μg/g DW), isoquercetin (400 μg/g DW) and rutin (300 μg/g DW). Compared to the untransformed plants, flavonoid levels increased 1.9-6-fold and 1.6-4-fold in rol B and rol C transgenics, respectively. RT qPCR analysis showed a variable expression of the flavonoid biosynthetic genes, including those encoding phenylalanine ammonia-lyase and chalcone synthase, which were found to be relatively more expressed in transformed than wild-type plants, thus correlating with the metabolite concentration. Methanolic extracts of transgenics showed higher antioxidant capacity, reducing power, and protection against free radical-induced DNA damage. Among the transgenic plants, those harboring rol B were slightly more active than the rol C-transformants. Conclusion: As well as demonstrating the effectiveness of rol genes in inducing plant secondary metabolism, this study provides insight into the molecular dynamics of the flavonoid accumulation pattern, which correlated with the expression of biosynthetic genes. [ABSTRACT FROM AUTHOR]

Diabetes and cancer are common diseases worldwide with terrific effect on human health. In the present study, a high valued medicinal plant Artemisia carvifolia Buch was subjected for evaluation of anticancer and antidiabetic potential. Previously produced rol B and rol C gene transgenic plants of A. carvifolia were also compared with the wild type plant for a differential count of cytotoxicity and antidiabetic activity. Lowest IC 50 values were shown by rolB transgenic line TB4 for alpha-glucosidase (838.6 μg/ml), alpha-amylase (742.8 μg/ml) and dipeptidyl peptidase-4 (1300 μg/ml) in contrast to the wild type plant which showed IC 50 values of 1608.4 μg/ml for alpha-glucosidase, 1973.8 μg/ml for alpha-amylase and 1800 μg/ml for dipeptidyl peptidase-4. Among rolC transgenic plants, TC1 showed lowest IC 50 value i.e. 873 μg/ml for alpha-glucosidase, 747.7 μg/ml for alpha-amylase and 1400 μ/ml for dipeptidyl peptidase-4. Viability of the cancer cells including HeLA, HePG2 and MCF7 decreased to 80% when treated with methanolic extract of the plant and it decreased to 70% when treated with n-hexane extract. Cytotoxic effect was found more enhanced when cells were treated with both the extracts combined, showing synergism between flavonoids and artemisinin. Rol B transformants showed slightly better activity than the rol C transformants which were found superior in activity than the wild type plant. Metabolite profiling by ESI/MS-TOF showed the involvement of significant plant secondary compounds in antidiabetic and anticancer potential in the extracts of transgenic lines. Vital amino acids, substantial phenylpropanoids and important phytochemicals were detected at a higher level in rol B and rol C transgenic plants than wild type plants. [ABSTRACT FROM AUTHOR]