Plant tissue culture techniques

The chemical synthesis of natural flavours started some time ago with the synthesis of coumarin in 1868 and vanillin in 1874 [7]. The development of the petrochemical industry and the availability of cheap oil has meant that most of the plant-derived products are now synthesised from crude oil. In addition, flavours can now be produced using microbial cultures. Thus, to achieve sustainable development plants will have to provide many of the products currently produced from petrochemicals, including flavours. In this chapter the possible use of plant tissue culture techniques and processes in the sustainable production of flavours is outlined and discussed. 

Plant tissue culture technique is one of the promising tools to ensure sustainable use of plant resources. There are three main strategies used in the biotechnological application of medicinal plants. The first is micropropagation for mass production of nurseries, the second is synthetic/artificial production of secondary metabolites of medicinal value and the third is molecular breeding for crop improvement. 

Plant tissue culture technique provides completely controlled conditions to elucidate the growth and physiology of the cells and to study host-parasite interactions at the cellular level. There exists probably single paper on this interesting technique in ergot research on cultivation of C. fusiformis on a Pennisetum typhoides cell culture. The authors (Roy and Kumar, 1985) established the methodology and studied nutritional demands of the mixed culture with respect to the growth and alkaloid production. 

In recent years, plant tissue culture techniques have been applied to the production of food colors. Also the pigments of two fungi Monascusanka SiMMonascus purpureas are being considered for use in foods. These fungal pigments have been used as food colors and medicines in the Far East for hundreds of years. 

Compared with whole plants, there has been limited development of foreign protein expression systems specifically for use in tissue culture. Some modifications of expression constructs have resulted in improved protein accumulation or have allowed simplified protein recovery. However, in general, modified expression systems have been tested only in a restricted number of cases and have not resulted in the large increases in product yield required for plant cultures to compete with other foreign protein production vehicles. Transient expression techniques, for example using viral vectors, that have been developed for use in whole plants have not yet been applied in plant tissue culture. 

The techniques of plant tissue culture offer a number of options in the quest for... 

Opium poppy Papaver somniferum L., Papaveraceae) is one of the most important medicinal plants and has been cultivated since early centuries. Opium, the dried cytoplasm of a specialized internal secretory system called the laticifer, is normally collected from the unripe capsule. It is the source for the commercial production of medicinally important alkaloids, morphine, codeine, thebaine, noscapine and papaverine [130, 131], Fig. (61). Morphine, which has strong addictive property, is still the most effective analgesic for the treatment of mortal cancer patients in modem medicine. Codeine is commonly used as an antitussive. However, field cultivation of this plant has been limited since 1953 by the United Nations Opium Conference Protocol to prevent narcotic crimes. Therefore, establishing tissue culture technique for the production of morphinan alkaloids seems to be desirable not only for medicinal purpose but also for decreasing abuse of opiates. 

The use of plant tissue culture as a tool for the elicitation and subsequent characterization of phytoalexins has been outlined (Section V. A) however, the technique has been widely... 

Having produced and selected a desirable strain, the breeder must then produce sufficient numbers of plants to test for trait stability and determine optimal conditions for commercial production. Unlike annuals that produce abundant seed, perennials with long generation times such as forest trees are a challenge to the plant breeder. For species such as conifers, advances in tissue-culturing techniques have transformed production processes in both the development and the marketing phases. 

Tissue culture techniques have been Increasingly used In plant breeding. An outstanding success utilizing this method was achieved by Improving palm oil production (13). Similar techniques are now being applied to the coconut palm (14). 

New methods in biotechnology such as plant tissue culture, the application of recombinant DNA-techniques to plants and the biotransformation of oleo-chemlcals by immobilized enzymes and microorganisms hold promise to a)... 

Therefore, this section of the Symposium was specifically organized to examine (a) the classic procedures of plant breeding as it applies to the modification of oil crops, (b) the newer tissue culture techniques for clonal propagation of elite plants, (c) recent procedures for mutagenesis and their application to basic problems in plant lipid biochemistry and finally (d) the employment of molecular biology and recombinant DNA techniques in specific problems. Additional poster presentations further amplified the approaches of the new technique. 

During the 1960s the techniques of plant tissue culture developed rapidly. The ability to recover complete plants from aseptic culture quickly led to the realisation that this technique provided a rapid multiplication method for clonal propagation of selected individual plants with elite qualities. 

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