Biohydrogenation Pathway of α-Linolenic Acid in Rumen of Dairy Cow In Vitro
by
, , , and
Guoxin Huang
1,2,3,†
,
Liya Guo
4,†,
Meiqing Chen
1,2,
Xufang Wu
1,2,
Wenhao Tang
1,2,
Nan Zheng
1,2, 
Shengguo Zhao
1,2,
Yangdong Zhang
1,2,* and
Jiaqi Wang
1,2,* 
1
Key Laboratory of Quality & Safety Control for Milk and Dairy Products of Ministry of Agriculture and Rural Affairs, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing 100193, China
2
State Key Laboratory of Animal Nutrition, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, No. 2 Yuanmingyuan West Road, Beijing 100193, China
3
College of Animal Sciences and Technology, Northeast Agricultural University, Harbin 150030, China
4
Henan Institute of Science and Technology, Xinxiang 453003, China
*
Authors to whom correspondence should be addressed.
†
Guoxin Huang and Liya Guo contributed equally.
Animals 2022, 12(4), 502; https://doi.org/10.3390/ani12040502
Submission received: 27 December 2021
/
Revised: 14 February 2022
/
Accepted: 14 February 2022
/
Published: 17 February 2022
Simple Summary
Few studies have investigated a relationship between t9,c12,c15-C18:3 and ALA, an α-Linolenic acid c9,c12,c15-C18:3 in the rumen. These results indicated that t9,c12,c15-C18:3 was an intermediate of the α-linolenic acid shifted rumen biohydrogenation pathway. This study hypothesized a pathway for α-linolenic acid biohydrogenation in rumen.
Abstract
The t9,c12,c15-C18:3 as an isomer of α-linolenic acid (c9,c12,c15-C18:3; ALA), has been recently detected in milk, but has not been found in the rumen. This study hypothesized that it may be a biohydrogenation product of ALA in rumen and aimed to explore whether it was present in the rumen and help to understand the rumen biohydrogenation mechanisms of ALA. The in vitro experiment included two treatments, a control check (CK group) with 50 µL ethanol added, and ALA group with 50 µL ethanol and 2.6 mg ALA (ALA addition calculated by 1.30% of dry matter base of diet); each sample of fermentation fluid had the composition of C18 fatty acids analyzed at 0, 0.5, 1, 2, 3, 4, 5, and 6 h. The results showed that no t9,c12,c15-C18:3 was detected in the CK group, but ALA addition increased the concentration of t9,c12,c15-C18:3 in fermentation fluid. The content of t9,c12,c15-C18:3 peaked 1 h after fermentation, then declined gradually. At 1 h, no t9c12c15-C18:3 was detected in the fermentation fluid of the CK treatment. The results suggested that ALA converted to the isomer t9,c12,c15-C18:3 through biohydrogenation in the rumen. The addition of ALA can also increase the concentration of t9,c12-C18:2, c9,t11-C18:2, c12-C18:1, t11-C18:1, t9-C18:1, and c6-C18:1 in fermentation fluid. It was concluded using an in vitro experiment that t9,c12,c15-C18:3 was a product of rumen biohydrogenation of ALA.
Keywords:
α-Linolenic acid; t9c12c15-C18:3; rumen biohydrogenation; in vitro
