Callus tissues derived from seedlings of roselle (Hibiscus sabdariffa L.) were shown to produce two cyanidin glycosides as major anthocyanin pigments. Both callus growth and anthocyanin synthesis were remarkably stimulated by 2,4-dichlorophenoxyacetic acid. The highest anthocyanin yield was observed when 1 μM 2,4-D in combination with 0.1-1 μM kinetin was supplemented to the culture medium. In contrast, gibberellic acid showed inhibitory effect on anthocyanin production.
Time-course changes in anthocyanin accumulation, phenylalanine ammonia-lyase activity and chalcone synthase activity were examined in roselle callus tissues incubated under different culture conditions. Phenylalanine ammonia-lyase activity was not affected by either the kind of auxin supplemented to the medium or light regime. In contrast, chalcone synthase activity was markedly suppressed when the callus was cultured with a medium containing indole-3-acetic acid instead of 2,4-dichlorophenoxyacetic acid (2,4-D) or in the dark. The results imply that in roselle callus cultures chalcone synthase plays a more important role in anthocyanin biosynthesis regulated by 2,4-D and light irradiation than phenylalanine ammonialyase.
The effects of various macronutrients on growth and anthocyanin formation in callus cultures of roselle (Hibiscus sabdaritfa L.) were investigated. Of the nutritional factors examined the type and concentration of carbon and nitrogen sources and phosphate concentration showed marked effects on the growth and anthocyanin production. Utilization of an optimized medium based on the results obtained in the present investigation resulted in a 2.5 fold increase in the anthocyanin content Potential exists for application of a two-stage culture method for the production of anthocyanin pigment Introduction Calyces of roselle (Hibiscus sabdariffa L.) contain cyanidin and delphinidin glycosides1) and have been used for making jelly, jams, beverages and food colorants2). Cultured roselle cells might potentially be a suitable source for large scale production of anthocyanin pigments. In a previous paper3) we reported that callus tissues derived from seedlings of roselle could accumulate anthocyanin pigments tentatively identified as cyanidin-3-monoglucoside (major pigment) and cyanidin-3-xylosylglucoside. Anthocyanin formation in the callus markedly enhanced by 2, 4-D and inhibited by gibberelic acid.The present paper describes the effects of macronutrients on cell growth and anthocyanin production of roselle callus as well as an optimized growth and production medium based on the results obtained in this study. Materials and MethodsPlant material and culture method. Callus tissues derived from seedlings of roselle were subcultured at 1-month intervals on Linsmaier and Skoog (LS) basal agar medium4) supplemented with l p M 2, 4-D and l p M kinetin at 25 under 3, 000 lux illumination (16 hr/day). For investigating the influence of various macronutrients, callus tissues (ca 0.2 g) were transferred onto 20 ml of test medium in 50 ml Erlenmeyer flasks and incubated at 25 under illumination for four weeks before harvest. All the test media contained both 2, 4-D and kinetin at 1 uM level.Extraction and quantitative analysis of anthocyanin. Fresh callus tissues were homogenized with 1% methanolic HCl in a mixer. The homogenate was allowed to stand overnight at 4 and then filtered. Absorbance of the filtrate was measured at 530 nm and the anthocyanin content was calculated as a percentage of fresh weight of callus using the molecular extinction coefficient (log E 4.47) for cyanidin-3-monoglucoside5). Results and DiscussionEffects of carbon sourceAlthough sucrose as a carbon source can support both growth and secondary metabolite production in callus and suspension cultures of plant cells, other carbon sources can also be effective. The effects of different carbon sources at 3% concentration on the growth and anthocyanin production of roselle callus are shown in Fig, 1. As regards anthocyanin formation glucose was as effective as sucrose, whereas fructose and maltose could support anthocyanin formation to a limited extent. In contrast, sucrose was most effective for cell growth; glucose, fructose and maltose were much inferior to suc...
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.