The synthetic potential of immobilised cells of Capsicum frutescens Mill cv. annuum

Abstract

Cells of Capsicum frutescens Mill. cv. annuum, immobilised in reticulate polyurethane foam, produced higher yields of capsaicin, the pungent principle of Chilli pepper fruits, than did freely-suspended cells, when batch-cultured in a medium conducive to culture growth. In the absence of specific precursors to capsaicin, immobilised cells produced between two and three orders of magnitude higher yields than did suspended cells over 5-d or 10-d culture periods (typically up to 4 or 5 mg capsaicin g(-1) dry weight l(-1) medium compared with up to 30 μg g(-1)l(-1), respectively). These results were reflected by an increased rate and extent of incorporation of L-[U-(14)C]phenylalanine into capsaicin in immobilised as compared with freely-suspended cells, and evidence is presented for an inverse relationship between incorporation of [(14)C]phenylalanine into protein and capsaicin. The accumulation of capsaicin can be experimentally manipulated and increased by supplementing the medium with precursors of capsaicin such as phenylalanine and isocapric acid and by reducing the growth rate of immobilised cells by omitting growth regulators from the medium. The importance of these observations is discussed.

Transformation of Chilli Pepper (Capsicum frutescens) with a Phenylalanine Ammonia-Lyase Gene

“…The relationship between the synthesis and accumulation of capsaicin has been studied in plants and cultured cells of C. frutescens [1][2][3][4] . Future progress in understanding the regulation of capsaicin accumulation could be significantly accelerated by the application of genetic manipulation techniques.…”

Overview of Yield Improvement Strategies for Secondary Metabolite Production in Plant Cell Culture

“…While there are many examples of the use of immobilization (Payne et al, 1992), there are relatively few with food ingredients. However, capsaicin (Lindsey and Yeoman, 1984;Ravishankar et aI., 1988) and caffeine (Furuya et al, 1990;Kurata and Furusaki, 1993) are examples of food ingredients produced in immobilized cell cultures.…”

Diosgenin formation by freely suspended and entrapped plant cell cultures of Dioscorea deltoidea

“…Intentional aggregation was beneficial for cells of pepper (Capsicum frutescens) where capsaicin accumulations were as much as 3 orders of magnitude greater than in pepper cells in suspension. 22 In other research, intentionally aggregated cells of Dioscorea deltoidea cultured in 30 g/L sucrose produced 40% more diosgenin than cells in ~uspension.~~ However, plant cells entrapped between permeable membranes produced smaller amounts of phenolics than those in suspension cult~r e ,~~ reportedly due to a "reduction of respiratory stress." Methods for controlling plant cell aggregation include entrapment and encapsulation.…”