Figure 4 Bioconversion of exogenous substrates by plant cell cultures.
The potential of peppermint (Mentha X piperita) cell suspension cultures to synthesize menthol has been investigated intensively. Studies showed that peppermint cells possess extensive hydroxylation activity toward terpenes. After application of the biosynthetic precursors (—)-(4R)- and (+)-(4S)-isopiperitones to cell suspension cultures, metabolism yielded the corresponding 7-hydroxyisopiperitones, which were concomitantly converted into the respective glucopyranosides (67).
The flavor synthesis of various Allium tissue cultures (onion, garlic, and chive) was less productive when compared with the respective plants (68). This was attributed to the low aroma precursor concentrations inside the cells rather than to the C-S lyase activity. Based on the knowledge of the well-characterized biosynthetic pathways to the flavor precursors (+)-S-alk(en)yl-L-cysteine sulfoxides (ACSOs) in Allium species, attempts were made to alter the flavor profile of onion root cultures by feeding of aroma precursors. Addition of cysteine, glutathione, and methionine increased the yields of methyl- and propenylcysteine sulfoxides, and the ratio of the pro-penyl to the methyl form was shifted significantly depending on the amount and type of the precursor used. S-Ethyl-L-cysteine sulfoxide, which is not a naturally occurring compound, was produced by application of ethanethiol to the root cultures, indicating the possible use of such cultures for the production of novel homologous metabolites (69).
Incubation of suspended, stationary phase cells of grapefruit with exogenous valencene led to the intermediary formation of the 2-hydroxy derivative, followed by conversion to the 2-oxo compound, nootkatone. The transformation rate was 68% in 24 hours, and when the concentration of about 0.7 mg L_1 was reached, it was maintained for another 48 hours without noticeable change (50).
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Our internal organs, the colon, liver and intestines, help our bodies eliminate toxic and harmful matter from our bloodstreams and tissues. Often, our systems become overloaded with waste. The very air we breathe, and all of its pollutants, build up in our bodies. Today’s over processed foods and environmental pollutants can easily overwhelm our delicate systems and cause toxic matter to build up in our bodies.