Enhancement of flavour biosynthesis from strawberry (Fragaria x ananassa) callus cultures by Methylobacterium species
Two important character-impact compounds of strawberry flavour, the furanones 2,5-dimethyl-4-hydroxy-2H-furan-3-one (DMHF) and 2,5-dimethyl-4-methoxy-2H-furan-3-one (mesifuran) were synthesized by strawberry tissue cultures derived from a cultivated species (Fragaria × ananassa, cv. Elsanta) after these were treated with Methylobacterium extorquens. These flavour compounds were analysed by HPLC-UV and their levels were compared in the treated and control tissues. In Methylobacterium extorquens treated callus cultures DMHF and mesifuran levels were 5.9 and 11.4 µg/g of fresh weight of callus respectively, compared to zero in the untreated ones. When Methylobacterium extorquens was fed with 1,2-propanediol, 2-hydroxy-propanal (lactaldehyde) was formed. This bacterial oxidation of 1,2-propanediol to lactaldehyde linked with the presence of 1,2-propanediol in strawberry suggests that the increased levels of the two furanones in the treated strawberry cultures is the result of Methylobacterium extorquens oxidative activity on 1,2-propanediol and the bioconversion by the plant cells of this oxidation product, lactaldehyde to DMHF and mesifuran.
Unable to display preview. Download preview PDF.
- Dourtoglou V (1986) Production of natural flavourings, perfumes and other fine chemicals by infected plants. Symbiosis 2: 189–200Google Scholar
- Fischer N & Hammerschimdt FJ (1992) A contribution to the analysis of fresh strawberry flavour. Chem. Mikrobiol. Technol. Lebensm. 14: 141–148Google Scholar
- Hirvi T (1983) Mass fragmentographic and sensory analyses in the evaluation of the aroma of some strawberry varieties. Lebensm. Wiss. Technol. 16: 157–161Google Scholar
- Holden MA, Holden PR & Yeoman MM (1988) Elicitation of cell cultures. In: Robins RJ & Rhodes MJC (eds) Manipulating Secondary Metabolism in Culture (pp 57–65). Cambridge University Press, CambridgeGoogle Scholar
- Latrasse A (1991) Fruits III. In: Maarse H (ed) Volatile Compounds in Foods and Beverages (pp 329–387).Marcel Dekker, New YorkGoogle Scholar
- Lindsey K & Jones MGK (1989) Manipulation of resistance. In: Plant Biotechnology in Agriculture, (pp 184–214). John Wiley & Sons, ChichesterGoogle Scholar
- Morrison RT & Boyd RN(1987) Aldehydes and ketones. In: Organic Chemistry (pp 759–800). Allyn and Bacon Inc, BostonGoogle Scholar
- Pisarnitskii AF, Demechenko AG, Egorov IA & Gvelesiani RV (1992) Methylpentoses are probable precursors of furanones in fruits. Appl. Biochem. Microbiol. 28: 97–100Google Scholar
- Schreier P (1980) Quantitative composition of volatile constituents in cultivated strawberries, Fragaria ananassa cv. Senga Sengana, Senga Litessa and Senga Gourmella. J. Sci. Food Agric. 31: 487–494Google Scholar
- Vaughn SF, Spencer GF & Shasha BS (1993) Volatile compounds from raspberry and strawberry fruit inhibit postharvest decay fungi. J. Food Sci. 58: 793–796Google Scholar
- Zabetakis I& Gramshaw JW (1997) 1,2-Propanediol in strawberries and its role as a flavour precursor. Food Chem. (in press)Google Scholar
- Zabetakis I, Gramshaw JW & Moutevelis-Minakakis P (1997) The role of 2-hydroxypropanal in the biosynthesis of 2,5-dimethyl-4-hydroxy-2H-furan-3-one in strawberry (Fragaria × ananassa, cv. Elsanta) callus cultures. J. Chem. Soc. Perkin Transactions I (submitted)Google Scholar