Determination of the Total Phenolic Content in Grapevine Shoots with Folin Ciocalteu Method
Georgia is one of the oldest wine regions in the world. Wine industry generates a high amount of by-products, such as shoots, canes, pomace etc., left from grape processing. The interest to these products is growing, as they can be used as a cheap and easily available source of raw materials for the recovery of a lot of bioactive substances for pharmaceutical and cosmetic applications instead of being treated as waste. Polyphenolic compounds are the most valuable of bioactive substance derived from vineyard/wine by-products. The aim of the study was selection of the optimal extraction conditions for TPC (total polyphenol content) from grapevine shoots, to optimize a method for calculation of TPC and evaluation of possible variations of the Folin-Ciocalteu method applied to the shoot raw material and determine TPC in shoots of different samples of Georgian grapevine. Three different samples of raw material shoots were collected in June-July 2019 in Kahketi region (Georgia) - Rkatsiteli (Arkhilo), Rkatsiteli (Alvani) and Saperavi (Arkhilo). The total Polyphenol extraction optimal conditions were selected and quantity was determined expressed as Rutin content. Developed method showed linarity, Precision, Accuracy and Selectivity. Comparative determination of TPC in different samples of grapevine was conducted according to the described method. Study results demonstrated, that shoots of Rkatsiteli (Arkhilo), Rkatsiteli (Alvani) and Saperavi (Arkhilo) contain sum of Polyphenols and the highest value was shown in Rkatsiteli (Arkhilo).
D. Rusjan, R. Veberic and M. Mikulic-Petkovsek. The response of phenolic compounds in grapes of the variety ‘Chardonnay’ (Vitis vinifera L.) to the infection by phytoplasma Bois noir. European journal of plant pathology 133, 1-10 (2012).
Doshi, P.; Adsule, P.; Banerjee, K.; Oulkar, D. Phenolic compounds, antioxidant activity and insulinotropic effect of extracts prepared from grape (Vitis vinifera L.) byproducts. J. Food. Sci. Technol. 2015, 52, 181-190
Elizabeth A Ainsworth, Kelly M Gillespie, Estimation of total phenolic content and other oxidation substrates in plant tissues using Folin-Ciocalteu reagent, Published online 12 April 2007; doi:10.1038/nprot.2007.102
Gonzalez-Centeno, M.R.; Comas-Serra, F.; Femenia, A.; Rossello, C.; Simal, S. Effect of power ultrasound application on aqueous extraction of phenolic compounds and antioxidant capacity from grape pomace (Vitis vinifera L.): Experi mental kinetics and modeling. Ultrason. Sonochem. 2014, 22, 506-514.
Magalha'es, L.M., Segundo, M.A., Reis, S., Lima, J.L. & Rangel, A.O. Automatic method for the determination of Folin-Ciocalteu reducing capacity in food products. J. Ag- ric. Food Chem. 54, 5241-5246 (2006).
Putkaradze R., Perspectives Of Georgian Wine Export On The Global Market.
Robards, K. & Antolovich, M. Analytical chemistry of fruit bioflavonoids a review. Analyst 122, 11R-34R (1997).
Rong Tsao, Chemistry and Biochemistry of Dietary Polyphenols, Nutrients 2010, 2, 1231-1246.
Xia, L.; Xu, C.; Huang, K.; Lu, J.; Zhang, Y. Evaluation of phenolic compounds, antioxidant and antiproliferative activities of 31 grape cultivars with different genotypes. J. Food Biochem. 2019, 43, 12626.
Xu, Y; Burton, S.; Kim, K.; Sismour, E. Phenolic com¬pounds, antioxidant, and antibacterial properties of pomace extracts from four Virginia-grown grape varieties. Food Sci. Nutr. 2016, 4, 125-133.
Zilich, O.V; Schweiggert-Weisz, U.; Eisner, P.; Ker- scher, M. Polyphenols as active ingredients for cosmetic products. Int. J. Cosmet. Sci. 2015, 37, 455-464.