Studies on Tissue Culture System for the Production of Food Colours from Beta Vulgaris L.

Mohamed Yahya, Khan (2006) Studies on Tissue Culture System for the Production of Food Colours from Beta Vulgaris L. PhD thesis, University of Mysore .

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Abstract

Plants are a vast resource of a number of chemical substances, which may be primary or secondary metabolites. Primary metabolites are those, which are directly synthesized and encoded by their respective genes or by basic photosynthetic process. Secondary metabolites are produced by plants, which play a major role in the defense mechanisms and adaptation of plants to their environment. These molecules largely contribute to plant fitness by interacting with the ecosystem. The plant secondary metabolites have been classified according to their biosynthetic pathways. Four large families are generally considered i.e. phenolics, terpenes, sterols and alkaloids. Plant secondary metabolites have been used from centuries in traditional medicine due to their large biological activities. They are also useful as food additives, flavours, colourants and pharmaceuticals. It has been established that despite rapid progress in applied chemistry 25% of the molecules used in pharmaceutical industry are still of plant origin. Conventionally plant secondary metabolites are obtained from field grown plants. However recently plant cell cultures have been exploited for the production of various secondary metabolites of food and pharmaceutical importance. Roots are the most important part of the plant system and are a source of many valuable products such as pharmaceuticals, insecticides, colours, flavours, enzymes and others. They are the major sites of metabolite synthesis and storage, which exhibit indefinite growth because of the meristamatic activity of root tip meristem. Many compounds that are scarcely synthesized such as coumarins, caffeic acid esters and cathecins in undifferentiated cells are produced at higher levels in root cultures. Among the in vitro culture systems, the cultured cell suspensions are not gained momentum because of their instability and non-uniformity of the product formation. Hence the differentiated organ cultures such as hairy root cultures was widely studied. Hairy root cultures are used as alternative production systems for secondary metabolites due to their tremendous potential to higher growth rate and uniform product formation. Being organized, they are amenable for scaling-up in bioreactors which is an added advantage. The metabolite pattern found in hairy roots is similar, if not always identical to that of plant roots. A major characteristic of hairy roots is the concomitant production of secondary metabolites with growth. Hence it is possible to get a continuous source of secondary metabolites from actively growing hairy roots. Colour in one form or the other has been added in foods for centuries. Natural colourants from plant sources are receiving growing interest from both food manufacturers and consumers in the continuing replacement of synthetic dyes. However substitution of synthetics with their natural alternatives presents a challenge due to higher stability of the former with respect to light, oxygen, temperature, and pH. Betalains are red pigments found in abundance in Beta vulgaris L. roots. They have been used as natural additives for food, drugs and cosmetic products in form of beet juice concentrates or beet products. Recently several investigations on hairy root cultures of red beet was reported. Hairy root cultures of Beta vulgaris L are an alternative source for the continuous production of betalains. In view of this background a series of experiments were designed and carried out i) To establish clones of hairy roots using different strains of Agrobacterium rhizogenes, different explants from beet root plants and different varieties of Beta vulgaris L for selection of superior clone looking at growth, morphological characteristics and pigment production. ii)To study effect of medium components i.e. major and minor nutrients to enhance the growth and production of betalains. Influence of growth regulators on growth and production of betalains in Beta vulgaris L. hairy roots. iii) To study the stability of betalains obtained from the hairy root cultures of Beta vulgaris l. and strategies employed to improve the stability. Metal ion stress studies to know enhance the antioxidant enzyme status in hairy root cultures of Beta vulgaris L. Short term sub acute and acute safety evaluation of betalain extracts in experimental animals. Protocol development for micropropagation of Beta vulgaris L. using shoots tips from seedling and mature beet root plants. Field evaluation of tissue culture obtained plants and seedling grown plants to study the growth and production of betalains.

Item Type:	Thesis (PhD)
Uncontrolled Keywords:	tissue culture food colours Natural Colour Beta vulgaris L.
Subjects:	600 Technology > 08 Food technology > 23 Vegetables > 06 Beet Root 600 Technology > 08 Food technology > 14 Physical properties > 01 Colours 500 Natural Sciences and Mathematics > 10 Plants > 05 Tissue Culture
Divisions:	Plant Cell Biotechnology
Depositing User:	Food Sci. & Technol. Information Services
Date Deposited:	13 Feb 2008 05:35
Last Modified:	28 Dec 2011 09:32
URI:	http://ir.cftri.res.in/id/eprint/1643

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