The gene that increases peach aroma compounds

Aroma is a critical indicator of the sensory characteristics associated with fruit quality. In peaches (Prunus persica L., Rosaceae family), ?-decalactone is one of the most important chemicals contributing to the unique aroma of peaches, further activating human olfactory receptors. Esters present in peaches also significantly contribute to their "fruity" aroma. Origin of lactones and estersLactones and esters are molecules derived from linoleic acid, a polyunsaturated fatty acid biosynthesized from another unsaturated fatty acid, oleic acid. This process is catalyzed by the enzyme fatty acid desaturase (known as FAD). Moreover, linoleic acid is an important precursor in the biosynthesis of short-chain aromatic volatile compounds. Additionally, polyunsaturated fatty acids like linoleic acid can enhance peach tolerance to cold stress by maintaining cell membrane fluidity. Fatty Acid Desaturase Enzymes (FAD) Different FAD enzymes exist in plants, and linoleic acid is primarily stored as triacylglycerol. The desaturation process occurs by introducing a double bond at the ?-12 position of oleate to form linoleate, catalyzed by the enzyme fatty acid desaturase 2 (FAD2). FAD2 is a typical plant desaturase, bound to plasma membranes, involved in vegetable oil biosynthesis, seed development, and tolerance to cold and salinity stress. The gene that increases peach aroma compoundsPrevious studies suggested that the PpFAD2 gene could be a candidate involved in peach aroma biosynthesis. Scientists developed a transgenic fruit (PpFAD2?1) where the expression of the PpFAD2 gene revealed increased levels of two unsaturated fatty acids (linoleic acid and linolenic acid) and peach aroma compounds (including hexyl acetate, ?-dodecalactone, ?-decalactone, ?-octalactone, and ?-hexalactone) during postharvest storage, especially in recovery, when fruits were placed at room temperature after cold treatment at 4 ?. Since peaches are typical climacteric fruits, they are often stored at low temperatures post-harvest to slow down ripening and reduce deterioration. However, they are sensitive to cold damage, and volatile compounds tend to decrease under these conditions. This study provides new insights into the role of PpFAD2 in regulating peach aroma biosynthesis, which could contribute to sustainable fruit storage management and the development of new varieties. ReferencesPeng, B.; Gu, Z.; Zhou, Y.; Ning, Y.; Xu, H.; Li, G.; Ni, Y.; Sun, P.; Xie, Z.; Shi, S.; Dark, A.; Song, Z. (2023). Potential role of fatty acid desaturase 2 in regulating peach aroma formation. Postharvest Biology and Technology, 204: 112473. Hern?ndez, M. L.; Mancha, M.; Rivas, J. M. M. (2005). Molecular cloning and characterization of genes encoding two microsomal oleate desaturases (FAD2) from olive. Phytochemistry, 66:12 (1417-1426). Lee, K. R.; Kim, S. H.; Go, Y. S.; Jung, S. M.; Roh, K.H.; Kim, H. B.; Suh, M. C.; Lee, S.; Kim, H. U. (2012). Molecular cloning and functional analysis of two FAD2 genes from American grape (Vitis labrusca L.). Gene, 509(2): 189-194. Zhang, B.; Xi, W.; Wei, W.; Shen, J.; Ferguson, I.; Chen, K. (2011). Changes in aroma-related volatiles and gene expression during low-temperature storage and subsequent shelf-life of peach fruit. Postharvest Biology and Technology, 60(1): 7-16. Imagehttps://br.freepik.com/fotos-premium/pessego-no-balcao-do-mercado-pilha-de-pessegos-maduros_32756925.htm Accessed on 10/10/2023.