Oak kombucha protects against oxidative stress and inflammatory processes B.D. V  azquez-Cabral a , M. Larrosa-P  erez b , J.A. Gallegos-Infante a , M.R. Moreno-Jim  enez a , R.F. Gonz  alez-Laredo a , J.G. Rutiaga-Qui ~ nones c , C.I. Gamboa-G  omez a , N.E. Rocha-Guzm  an a, * a Research Group on Functional Foods and Nutraceuticals, Departamento de Ingenierías Química y Bioquímica, TecNM/Instituto Tecnol ogico de Durango, Felipe Pescador 1830 Ote., 34080 Durango, Dgo., Mexico b School of Doctoral Studies & Research, European University of Madrid, Calle Tajo, s/n, Villaviciosa de Od on, ES-28670 Madrid, Spain c Facultad de Ingeniería en Tecnología de la Madera, Edificio D, Ciudad Universitaria, Universidad Michoacana de San Nicol as de Hidalgo, Av. Fco. J. Múgica S/N. Col. Felicitas de Río, Morelia, Michoac an C.P. 58040, Mexico article info Article history: Received 20 March 2017 Received in revised form 27 April 2017 Accepted 1 May 2017 Available online 3 May 2017 Keywords: Antioxidant Kombucha Quercus Anti-inflammatory Fermented beverages abstract Black tea infusion is the common substrate for preparing kombucha; however other sources such as oak leaves infusions can be used for the same purpose. Almost any white oak species have been used for medicinal applications by some ethnic groups in Mexico and could be also suitable for preparing kombucha analogues from oak (KAO). The objective of this research was to investigate the antioxidant activity and anti-inflammatory effects of KAO by examining its modulation ability on macrophage- derived TNF-alpha and IL-6. Herbal infusions from oak and black tea were fermented by kombucha consortium during seven days at 28  C. Chemical composition was determined by LC-ESI-MS/MS. The antioxidant activity of samples against oxidative damage caused by H 2 O 2 in monocytes activated (macrophages) was explored. Additionally, it was determined the anti-inflammatory activity using lipopolysaccharide (LPS) - stimulated macrophages; in particular, the nitric oxide (NO), TNF-alpha, and IL-6 production was assessed. Levels of pro-inflammatory cytokines IL-6 and TNF-alpha were signifi- cantly reduced by the sample treatment. Likewise, NO production was lower in treatment with kom- bucha and KAO compared with LPS-stimulated macrophages. Fermented beverages of oak effectively down-regulated the production of NO, while pro-inflammatory cytokines (TNF-alpha and IL-6) in macrophages were stimulated with LPS. Additionally, phytochemical compounds present in KAO decrease oxidative stress. © 2017 Elsevier B.V. All rights reserved. 1. Introduction Some fermented foods have transcended their sources to become everyday products in more than one continent; fermen- tations involved in these foods are of enormous complexity, and their study has provided us a wealth of biotechnology knowledge. An attractive bioprocess consists on the degradation of glucose and fructose through the fermentation action of a bacterial and yeast consortium called Kombucha [6]. This Kombucha is a fermented beverage that has been traditionally consumed in China for over 2200 years. This ancient beverage is composed of two portions: a floating biofilm of cellulose and the sour liquid broth [4]. Several positive effects have been reported, including gastro protective effect of the culture broth and probiotic potential of the Kombucha microbiome [1,13]. In particular, in the culture broth the main metabolites identified are gluconic and glucuronic acids, glycerol, phenolic acids and caffeine; some are associated with beneficial effects on health. The two main classes of involved polyphenols are flavonoids and phenolic acids. Their chemical and structural mod- ifications are due to biotransformation and metabolism by the kombucha consortium action, and have not been taken into ac- count in previous studies of kombucha analogues obtained from other sources. The biotransformation of flavonoids has been a topic of research due to the interest in explaining the correlation be- tween the beneficial properties of flavonoids and the structures of the active compounds. In Kombucha obtained from black tea, the * Corresponding author. E-mail address: nrocha@itdurango.edu.mx (N.E. Rocha-Guzman). Contents lists available at ScienceDirect Chemico-Biological Interactions journal homepage: www.elsevier.com/locate/chembioint http://dx.doi.org/10.1016/j.cbi.2017.05.001 0009-2797/© 2017 Elsevier B.V. All rights reserved. Chemico-Biological Interactions 272 (2017) 1e9