Abstract:
The photostability and photo degradation kinetics of water-soluble
monascus red pigments and yellow pigments was studied in this paper.Besides,effect of honeysuckle extract on the protection of water-soluble
monascus pigments were also studied in the study.The results showed that rule of degradation in the two
monascus pigments accorded with the first-order kinetics. Honeysuckle extract was effective in protecting the two
monascus pigments.According to the result of turbidity (NTU),the optimum addition of honeysuckle extract was 0.5 mg/mL.The photostability of
monascus red pigments was improved effectively by the honeysuckle extract under acidic conditions.When the pH value was 4,7,the survival rate of
monascus red pigments was 4.58-fold and 2.75-fold higher than the control,and the survival rates of
monascus yellow pigments were 5.93-fold and 1.75-fold higher than the control.The content of chlorogenic acid,one of its effective substances,was determined by high performance liquid chromatography (HPLC),and its content was 108.13 mg/g of the quality of honeysuckle extract dry powder. The 0.5 mg/mL honeysuckle extract,chlorogenic acid and V
C were respectively added into the
monascus yellow and red pigments,and the survival rate of
monascus red pigments were 2.18-fold,2.02-fold and 1.82-fold to the control after exposing in ultraviolet radiation for 180 minutes.And the survival rates of
monascus yellow pigments were 3.49-fold,3.20-fold and 2.56-fold to the control. Chlorogenic acid may be closely related to the effect of honeysuckle extract on color protection.