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Differential activities of fungi-derived tannases on biotransformation and substrate inhibition in green tea extract.
J Biosci Bioeng. 2014 Nov; 118(5):546-53.JB

Abstract

Tannases are important enzymes in the antioxidant potential of tea leaves. In this study, we evaluated the effect of two tannases (T1 and T2) on biotransformation of tea polyphenols and antioxidative activities from catechins in green tea extract (GTE). The T1 tannase-catalyzed reaction was inhibited by the addition of >2.0% GTE substrate, whereas the T2-catalyzed reaction was not inhibited, even by addition of 5.0% GTE. Furthermore, the T1 tannase-catalyzed reaction was inhibited by addition of 10 mg mL(-1) EGCG, whereas the T2 tannase-catalyzed reaction did not display any inhibitory effect. These results indicate that T2 tannase was more tolerant than T1 tannase to substrate inhibition in degallation reactions. Specifically, the substrate EGCG (90,687.1 μg mL(-1)) was transformed into gallic acid (50,242.9 μg mL(-1)) and EGC (92,598.3 μg mL(-1)) after 1-h treatment with T2 tannase (500 U g(-1)). The tannase-mediated product displayed higher in vitro radical-scavenging activity than the control. IC50 value of GTE on ABTS and DPPH radicals (46.1 μg mL(-1) and 18.4 μg mL(-1), respectively) decreased markedly after T2 tannase treatment (to 35.8 μg mL(-1) and 15.1 μg mL(-1), respectively). These results indicate that T2 tannase treatment of GTE enhanced its radical-scavenging activity, an increase that was also observed in the reaction using EGCG substrate. Taken together, our results revealed that T2 tannase is more suitable for biotransformation of catechins in GTE than T1 tannase, and T2 treatment provides an enhanced radical-scavenging effect.

Authors+Show Affiliations

Cosmax Bio INC, Jecheon 390-250, Republic of Korea.Department of Food and Nutrition, Korea University, Seoul 136-703, Republic of Korea; Department of Public Health Science, Graduate School, Korea University, Seoul 136-7033, Republic of Korea.Department of Food and Nutrition, Korea University, Seoul 136-703, Republic of Korea.Department of Food and Nutrition, Korea University, Seoul 136-703, Republic of Korea.Department of Food and Nutrition, Korea University, Seoul 136-703, Republic of Korea. Electronic address: sirchoi@hanmail.net.

Pub Type(s)

Journal Article

Language

eng

PubMed ID

24856576

Citation

Baik, Joo Hyun, et al. "Differential Activities of Fungi-derived Tannases On Biotransformation and Substrate Inhibition in Green Tea Extract." Journal of Bioscience and Bioengineering, vol. 118, no. 5, 2014, pp. 546-53.
Baik JH, Suh HJ, Cho SY, et al. Differential activities of fungi-derived tannases on biotransformation and substrate inhibition in green tea extract. J Biosci Bioeng. 2014;118(5):546-53.
Baik, J. H., Suh, H. J., Cho, S. Y., Park, Y., & Choi, H. S. (2014). Differential activities of fungi-derived tannases on biotransformation and substrate inhibition in green tea extract. Journal of Bioscience and Bioengineering, 118(5), 546-53. https://doi.org/10.1016/j.jbiosc.2014.04.012
Baik JH, et al. Differential Activities of Fungi-derived Tannases On Biotransformation and Substrate Inhibition in Green Tea Extract. J Biosci Bioeng. 2014;118(5):546-53. PubMed PMID: 24856576.
* Article titles in AMA citation format should be in sentence-case
TY - JOUR T1 - Differential activities of fungi-derived tannases on biotransformation and substrate inhibition in green tea extract. AU - Baik,Joo Hyun, AU - Suh,Hyung Joo, AU - Cho,So Young, AU - Park,Yooheon, AU - Choi,Hyeon-Son, Y1 - 2014/05/21/ PY - 2014/02/11/received PY - 2014/03/26/revised PY - 2014/04/16/accepted PY - 2014/5/27/entrez PY - 2014/5/27/pubmed PY - 2015/5/20/medline KW - Antioxidative activity KW - Biotransformation KW - Substrate inhibition KW - Tannase KW - Tea catechins SP - 546 EP - 53 JF - Journal of bioscience and bioengineering JO - J Biosci Bioeng VL - 118 IS - 5 N2 - Tannases are important enzymes in the antioxidant potential of tea leaves. In this study, we evaluated the effect of two tannases (T1 and T2) on biotransformation of tea polyphenols and antioxidative activities from catechins in green tea extract (GTE). The T1 tannase-catalyzed reaction was inhibited by the addition of >2.0% GTE substrate, whereas the T2-catalyzed reaction was not inhibited, even by addition of 5.0% GTE. Furthermore, the T1 tannase-catalyzed reaction was inhibited by addition of 10 mg mL(-1) EGCG, whereas the T2 tannase-catalyzed reaction did not display any inhibitory effect. These results indicate that T2 tannase was more tolerant than T1 tannase to substrate inhibition in degallation reactions. Specifically, the substrate EGCG (90,687.1 μg mL(-1)) was transformed into gallic acid (50,242.9 μg mL(-1)) and EGC (92,598.3 μg mL(-1)) after 1-h treatment with T2 tannase (500 U g(-1)). The tannase-mediated product displayed higher in vitro radical-scavenging activity than the control. IC50 value of GTE on ABTS and DPPH radicals (46.1 μg mL(-1) and 18.4 μg mL(-1), respectively) decreased markedly after T2 tannase treatment (to 35.8 μg mL(-1) and 15.1 μg mL(-1), respectively). These results indicate that T2 tannase treatment of GTE enhanced its radical-scavenging activity, an increase that was also observed in the reaction using EGCG substrate. Taken together, our results revealed that T2 tannase is more suitable for biotransformation of catechins in GTE than T1 tannase, and T2 treatment provides an enhanced radical-scavenging effect. SN - 1347-4421 UR - https://www.unboundmedicine.com/medline/citation/24856576/Differential_activities_of_fungi_derived_tannases_on_biotransformation_and_substrate_inhibition_in_green_tea_extract_ L2 - https://linkinghub.elsevier.com/retrieve/pii/S1389-1723(14)00143-1 DB - PRIME DP - Unbound Medicine ER -