Background. Recent consumption trends shows high consumer acceptability and growing medicinal interest in the biological value of kombucha tea. This tea is a sweetened tea leaf brew fermented with a layer containing mainly acetic acid bacteria, yeast and lactic acid bacteria. The main antioxidants in tea leaves are polyphenols, the consumption of which is proven to be benefi cial for human health, e.g. protecting from reactive oxygen species (ROS). The aim of the present research was to evaluate antiradical activity, total polyphenol content (TPC) and sensory value of kombucha tea brews. Material and methods. In the present study, Kombucha tea beverages were analyzed for TPC content, DPPH radical scavenging method and sensory value. Results. The highest TPC content and DPPH radical scavenging capacity values were evaluated in yellow tea samples, both unfermented and kombucha, which did not diff er within the storage time. The results of sensory evaluations of kombucha tea brews depend on the tea leaf variety used for preparing the drink. Conclusions. Research indicates that the fermentation process of tea brews with kombucha microbiota does not aff ect signifi cantly its polyphenol content and antiradical capacity, and retains its components' biological activity.

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With the popularization of intelligent manufacturing, manipulator has found ever wider application in various industries. A manipulator requires a real-time and fast control algorithm in order to improve the accuracy in all kinds of precise operations. This paper proposes an algorithm based on adaptive radial basis function (RBF) for approximating the parameters of the manipulator, and the adaptive equations are designed to automatically adjust the weight of RBF. Proportional integral (PI) robust based on dynamic error tracking is used in controller to reduce the steady state errors and enhance the anti-interference performance of the system. The global asymptotic stability of the system is demonstrated by defining an integraltype Lyapunov function. Finally, MATLAB is used to simulate the angular positions tracking and angular velocities tracking of the double joints manipulator. The results show that the manipulator can track the ideal output signal quickly and accurately and has good anti-interference performance.