Current evidence on physiological activity and expected health effects of kombucha fermented beverage.

Consumption of kombucha fermented tea (KT) has always been associated with different health benefits. Many personal experiences and testimonials of KT drinkers are available throughout the world on the ability of KT to protect against a vast number of metabolic and infectious diseases, but very little scientific evidence is available that validates the beneficial effects of KT. The aim of this review is to give an overview of the recent studies in search of experimental confirmation of the numerous KT health-promoting aspects cited previously. Analysis of the literature data is carried out in correspondence to the recent concepts of health protection's requirements. Attention is given to the active compounds in KT, responsible for the particular effect, and to the mechanisms of their actions. It is shown that KT can efficiently act in health prophylaxis and recovery due to four main properties: detoxification, antioxidation, energizing potencies, and promotion of depressed immunity. The recent experimental studies on the consumption of KT suggest that it is suitable for prevention against broad-spectrum metabolic and infective disorders. This makes KT attractive as a fermented functional beverage for health prophylaxis.

A novel and simple method for the purification of extracellular levansucrase from Zymomonas mobilis.

A new and simple method for the purification of extracellular levansucrase from Zymomonas mobilis from highly viscous fermentation broth was developed. After incubation of the fermentation broth with a fructose-polymer cleaving enzyme preparation (Fructozyme, Novozymes, DK) for 48 h, levansucrase precipitated as aggregates and was redissolved in a 3 M urea solution. By ongoing size-exclusion chromatography on Sephacryl S-300 the final levansucrase preparation was purified 100-fold and exhibited a specific activity of 25-35 U/mg(protein). The levansucrase was stable in 3 M urea solution for at least four months without inactivation. To maximize the enzyme yield the dynamic changes of extracellular levansucrase activity during fermentation were investigated. The highest levansucrase activity was observed during the logarithmic phase of growth (15-19 h of fermentation).