Bioprocessing of differentiated plant in vitro systems

Modeling hairy root tissue growth in in vitro environments using an agent-based, structured growth model

An agent-based model for simulating the in vitro growth of Beta vulgaris hairy root cultures is described. The model fitting is based on experimental results and can be used as a virtual experimentator for root networks. It is implemented in the JAVA language and is designed to be easily modified to describe the growth of diverse biological root networks. The basic principles of the model are outlined, with descriptions of all of the relevant algorithms using the ODD protocol, and a case study is presented in which it is used to simulate the development of hairy root cultures of beetroot (Beta vulgaris) in a Petri dish. The model can predict various properties of the developing network, including the total root length, branching point distribution, segment distribution and secondary metabolite accumulation. It thus provides valuable information that can be used when optimizing cultivation parameters (e.g., medium composition) and the cultivation environment (e.g., the cultivation temperature) as well as how constructional parameters change the morphology of the root network. An image recognition solution was used to acquire experimental data that were used when fitting the model and to evaluate the agreement between the simulated results and practical experiments. Overall, the case study simulation closely reproduced experimental results for the cultures grown under equivalent conditions to those assumed in the simulation. A 3D-visualization solution was created to display the simulated results relating to the state of the root network and its environment (e.g., oxygen and nutrient levels).

Elicitation of galanthamine biosynthesis by Leucojum aestivum liquid shoot cultures

The effects of methyl jasmonate and jasmonic acid on galanthamine production, phenolic acid content and growth of Leucojum aestivum L. shoot culture, cultivated in submerged conditions were investigated. The best time-point for addition of elicitors was during the exponential phase of the culture growth. The maximal contents of galanthamine and lycorine (226.9 μg/flask and 491.4 μg/flask, 1.36 and 1.67-fold higher compared to the control, respectively) were achieved after elicitation with jasmonic acid, whereas the elicitation with methyl jasmonte resulted in maximal accumulation of phenolic acids. It was demonstrated that the boosting effect of jasmonic acid on Amaryllidacea alkaloid biosynthesis was due to induction of the activity of tyrosine decarboxylase, whereas methyl jasmonate stimulates the biosynthesis of phenolic acids by inducing mainly the activity of phenylalanine ammonia-lyase.