Technological innovations find in nature a model of sustainability. Nature always achieves its goals by conserving its resources and completely recycling its waste. With this in mind, researchers from various fields have begun to observe it for inspiration to find solutions to everyday challenges and in the innovation of their products, developing more sustainable methodologies and processes that can generate less environmental impact.
Several studies have shown that biotechnology can be a sustainable alternative for obtaining aromatic ingredients for the fragrance industry. In this context, the following technological strategies can be highlighted: ingredients obtained through biocatalysis (using wild or engineered microorganisms and enzymes) and plant cell cultivation.
Biocatalysis
The use of enzymes (isolated or derived from microorganisms) as catalysts to promote specific modifications in a given substrate is known as biocatalysis.
Microorganisms contain a variety of enzymes such as oxidases, reductases, hydrolases, among others, which are capable of promoting selective reactions generating products of great chemical interest. For example, the fungus Penicillium digitatum can transform a substrate (limonene) present in the peels of citrus fruits into important aromatic compounds for perfumery such as perillyl alcohol, carvone, and α-terpineol. Through the biotransformation of isoeugenol by the bacterium Pseudomonas putida, vanillin and derivatives can be obtained; similarly, substances with rose-like olfactory notes such as 2-phenylethanol can be obtained from L-phenylalanine by the yeast Saccharomyces vini.
The genetic engineering of secondary metabolic pathways is the newest and most promising tool for improving the production of volatile ingredients. A recent study published by Maury and collaborators demonstrates the use of genetic engineering promoting the insertion of plant genes into yeasts of the genus Saccharomyces. Thus, these yeasts can produce substances important for the fragrance industry such as the major components of essential oils of Patchouli (patchoulol) and Sandalwood (α- and β-santalol).
In nature, we have the example of the enzymatic degradation of carotenoids that occurs naturally, generating derived aromatic compounds that exhibit fungicidal activity. An example of biocatalysis using free or immobilized enzymes as catalysts is the conversion of β-carotene into its phenolic and aromatic derivatives (β-ionone and β-damascenone).
Plant Cell Cultivation
Plant cell culture appears as another potential technique for the production of a wide variety of secondary metabolites. Each plant cell contains the genetic information necessary to produce the chemical components present in the plant as a whole. The totipotent capability (the possibility of forming any type of plant tissue) of meristematic (undifferentiated) cells allows for genetic and biochemical direction towards the development of specific parts of the plant. After the ideal part of the plant to be produced is chosen, we can direct an increase in the production of the compounds of interest by enriching the culture medium with specific chemical precursors to activate this biosynthetic pathway. Examples of the use of plant cell culture as an alternative for the production of aromatic compounds include the cultivation of plant cells from Perilla frutescens to produce monoterpenes, as well as the production of caryophyllene from cells of Lindera strychnifolia.
Despite many relevant advances, the direct application of these strategies on an industrial scale still faces some obstacles, such as low yield and the formation of a complex mixture of compounds that are difficult to separate. The optimization of these processes, both fermentative and enzymatic, for the industrial-scale production of high-value-added compounds remains an important technological bottleneck in order to meet the growing market trend for natural and quality aromatic raw materials. All of this makes the obtaining of aromatic ingredients through biotechnological processes an important area for research and development.
By Renata Rabelo Schefer and Noemi Jacques Vieira - Researchers from the Ingredient Science and Technology group at Natura.
Suggested reading:
[1] Krings, U.; Berger, R. G. Biotechnological production of flavours and fragrances. Appl. Microbiol. Biotech., 1998, 49, 1-8.
[2] Gounaris, Y. Biotechnology for the production of essential oils, flavours and volatile isolates. A review. Flavour Fragr. J., 2010, 25, 367–386.
[3] Carvalho, C.C.C.R., Fonseca M. M. R. Biotransformation of terpenes. Biotech. Adv., 2006, 24, 134–142.
[4] Duetz, W. A.; van Beilen, J. B.; Witholt, B. Biotransformation of limonene by bacteria, fungi, yeasts, and plants. Appl. Microbiol. Biotech., 2003, 61, 269–277.
[5] Yamada, M.; Okada, Y.; Yoshida, T.; Nagasawa, T. Biotransformation of isoeugenol to vanillin by Pseudomonas putida IE27 cells. Appl. Microbiol. Biotech., 2007, 73, 1025–1030.
[6] Etschmann, M.M.W.; · Sell, D.; Schrader, J. Biotechnological production of 2-phenylethanol. Appl. Microbiol. Biotech., 2002, 59, 1–8.
[7] Uenojo, M. and Pastore, G. M. β-Carotene biotransformation to obtain aroma compounds. Ciênc. Tecnol. Aliment., 2010, 30, 822-827.
[8] Maury, J.; Asadollahi, M. A.; Møller, K.; Schalk, M.; Clark, A.; Formenti, L. R.; Nielsen, J.
Reconstruction of a bacterial isoprenoid biosynthetic pathway in Saccharomyces cerevisiae. FEBS Let., 2008, 582, 4032-4038.
[9] Longo, M.A.; Sanromàn, M.A. Production of Food Aroma Compounds: Microbial and Enzymatic Methodologies. Food Techn. Biotech., 2006, 44, 335–353.
