Growth and anthocyanin accumulation rates of carrot suspension cultures grown with excess nutrients after semicontinuous culture with different limiting nutrients at several dilution rates, pHs, and temperatures

Abstract

When carrot cell cultures, after growth in semicontinuous culture, were transferred to media containing excess nutrients, they grew at different rates. The growth rates were generally higher after semicontinuous culture at higher dilution rates. There appears to be a limit on dilution rate above which growth rate does not increase. These changes were also displayed by clones from the parental culture. The possibility that these changes in growth rate reflect a need for the cultures to adapt to their new conditions is discussed. The growth rates of the cultures is markedly increased at 25 degrees C compared with 22 degrees C with little further increase at 28 degrees C. Growth rate is altered by less than 20% when pH is changed from 4.5 to either 5.5 or 4.2. The rates of anthocyanin accumulation by the cultures were similar under all conditions tested except at 22 degrees C. They were larger than the rates of dry weight accumulation. In contrast, the amounts of anthocyanin accumulated in the clones and in the parental cultures grown at pH 5.5 instead of pH 4.5 were very different. The observations were interpreted as showing that the clones differ in the rate of metabolism but not in the rate of synthesis of anthocyanins and that at pH 5.5 the rate of metabolism of anthocyanins but not the rate of synthesis is higher than it is at pH 4.5. The use of semicontinuous cultures as a source of inoculum for batch cultures rather than as a source of biomass for extraction of chemicals is discussed.

The scale-up of plant cell culture: Engineering considerations

“…Tal & Goldberg obtained good cell growth with little steroid synthesis in continuous fermentations of Dioscorea deltoidea [54]. Dougall and coworkers, in culturing Daucus carotaon a continuous basis demonstrated that factors which improve biomass productivity either do not affect product formation or actually inhibit it [104,105]. This naturally leads to a process whereby biomass and product synthesis are uncoupled.…”

Molecular understanding of anthocyanin biosynthesis activated by PAP1 in engineered redArtemisia annuacells and regulation of 2, 4-dichlorophenoxyacetic acid

“…Callus and cell suspension culture systems have been a good platform to understand the engineering of anthocyanin biosynthesis regulated by 2,4-D for a few decades (Ball 1967; Stickland and Sunderland 1972; Wellmann et al 1976; Dougall et al 1980; Al Qurraan et al 2012; Asano and Otobe 2011). Example models of callus and cell suspension cultures include carrot (Dougall et al 1980; Dougall et al 1983; Rose et al 1996; Hirner and Seitz 2000; Narayan et al 2005; Ozeki et al 2000), grape (Bao Do and Cormier 1991; Do and Cormier 1991a; Do and Cormier 1991b; Cormier et al 1992; Yousef et al 2004), and Catharanthus roseus (Hall and Yeoman 1986b, a). Based on those previous reports, the regulation of 2, 4-D can be summarized to two types.…”

Phenotypic differences in anthocyanin accumulation among clonally related cultured cells of carrot

“…Rates of anthocyanin accumulation (Dougall et al 1983) and degradation (Dougall & Vogelien 1987) were examined in extreme clones, and no difference was detected that would account for the difference in anthocyanin levels observed. The enzyme 4-coumaryl CoA ligase was examined in high-and low-accumulating subclones to investigate the possible role of isozymes of this enzyme in directing 4-coumaryl CoA to lignin biosynthesis, flavonoid biosynthesis and other pathways.…”