Assessment of Anti-nutritive Activity of Tannins in Tea By-products Based on In vitro Rumen Fermentation

作者：Kondo Makoto^*; Hirano Yoshiaki; Ikai Noriyuki; Kita Kazumi; Jayanegara Anuraga; Yokota Hiro omi

来源：Asian-Australasian Journal of Animal Sciences, 2014, 27(11): 1571-1576.

DOI：10.5713/ajas.2014.14204

• Tea By-product
• In vitro Rumen Fermentation
• Tannin
• Tannin Binding Agent

Nutritive values of green and black tea by-products and anti-nutritive activity of their tannins were evaluated in an in vitro rumen fermentation using various molecular weights of polyethylene glycols (PEG), polyvinyl pyrrolidone (PVP) and polyvinyl polypyrrolidone as tannin-binding agents. Significant improvement in gas production by addition of PEG4000, 6000 and 20000 and PVP was observed only from black tea by-product, but not from green tea by-product. All tannin binding agents increased NH3-N concentration from both green and black tea by-products in the fermentation medium, and the PEG6000 and 20000 showed relatively higher improvement in the NH3-N concentration. The PEG6000 and 20000 also improved in vitro organic matter digestibility and metabolizable energy contents of both tea by-products. It was concluded that high molecular PEG would be suitable to assess the suppressive activity of tannins in tea by-products by in vitro fermentation. Higher responses to gas production and NH3-N concentration from black tea by-product than green tea by-product due to PEG indicate that tannins in black tea by-product could suppress rumen fermentation more strongly than that in green tea by-product.

• 出版日期2014-11