Modeling the growth kinetics of cell suspensions of Randia echinocarpa (Rubiaceae) and characterization of their bioactive phenolic compounds

The fruit of Randia echinocarpa is commonly used in the Mexican traditional medicine to treat different diseases and ailments. The establishment of cell suspension cultures (CSC) is a viable alternative to obtaining bioactive compounds from this plant. Moreover, suitable kinetic models are necessary for optimal process control and simulation of plant cell cultures. Therefore, the objectives of this study were to model and estimate the growth kinetics of the CSC of R. echinocarpa, as well as characterize their phenolic profile by ultra-performance liquid chromatography coupled with mass spectrometry. Along the 34 d of culture, CSC of R. echinocarpa reached a dry cell biomass concentration of 15.16 g/L at day 20. The maximum specific growth rate (\({\mu }_{max}\)) was 0.15 d-1, with a duplication time (\({t}_{d}\)) of 4.62 d. The Logistic model adequately predicted the cell growth changes during the culture and the maximum dry cell content that the culture medium could sustain (approximate to 13.63 g/L). Ten phenolic compounds were identified in the biomass and four in the supernatants. The major phenolic compound in the biomass was chlorogenic acid (CA), with a concentration of 828.6 mu g/g at day 20. In the lyophilized supernatant, the major phenolic compound was salicylic acid (SA) with a concentration of 172.7 mu g/g at day 30. The production of CA was a growth-dependent process in contrast to the concentration of SA in the media. Our results indicate that CSC of R. echinocarpa could be a sustainable source to produce bioactive compounds such as CA and SA.