Application of esterase inhibitors: A possible new approach to protect unsaturated fatty acids from ruminal biohydrogenation

Abstract

General nutritional guidelines recommend reducing the consumption of fats originated from ruminant products. This is due to the ruminal biohydrogenation of unsaturated fatty acids (UFAs) which leads to the presence of unhealthy saturated or trans fats in ruminant products. Here, for the first time to our knowledge, we have focused on the main biochemical process which results in the saturation of UFAs. Rumen lipolytic activity (RLA) generates non-esterified fatty acids (NEFAs) in the rumen, which are a prerequisite for the biohydrogenation process to occur. We have examined different concentrations of pyridostigmine bromide (PB), of reversible cholinesterase inhibitor, in batch cultures containing 80 mg soybean oil, as a source of triglyceride. PB is the main active compound of an FDA approved drug for the treatment of myasthenia gravis and also pretreatment against nerve gas in humans. Our hypothesis was to evaluate PB as an inhibitor for RLA. In normal conditions, soon after triglycerides enter the rumen, they are hydrolyzed as a result and free fatty acids undergo the biohydrogenation process. Our results indicated that no significant (P > 0.01) reduction in linoleic acid (C18:2, v6) after 6 h incubation was observed for cultures containing PB with concentrations above 0.052 g/dL. We concluded that PB has the potential to inhibit RLA in cultures after 6 h of incubation. Such findings suggest the potential of PB to be utilized in vivo as a feed additive to inhibit biohydrogenation of unsaturated fatty acids in the rumen.Practical applications: The biohydrogenation of health benefitial unsaturated fatty acids in the rumen cause ruminant products, such as milk and meat, to contain highly saturated fats. Inhibition of rumen microbial lipolytic activity in vivo could increase the flow of unsaturated fatty acids for absorption and therefore, would have the potential to improve fatty acid composition of ruminant milk and meat. This would also have benefits for the animal. Abbreviations: FA, fatty acid; FAME, fatty acids methyl ester; NDF, neutral detergent fiber; NEFA, non-esterified fatty acid; PB, pyridostigmine bromide; PUFA, polyunsaturated fatty acid; RLA, rumen lipolytic activity; SFA, saturated fatty acid; UFA, unsaturated fatty acid Eur.

Rumen microbiota and dietary fat: a mutual shaping

“…A preliminary study using esterase inhibitors has shown promising results in vitro (Sargolzehi et al . ). Inhibition of ruminal lipase‐producing bacteria using an antilipase antibody affected several lipase‐producing bacteria, including B. fibrisolvens , and decreased BH in vitro (Edwards et al .…”

“…Because most dietary FA are glycerides and need lipolysis before BH, decreasing the rumen metabolism of FA could limit rumen BH. A preliminary study using esterase inhibitors has shown promising results in vitro (Sargolzehi et al 2015). Inhibition of ruminal lipase-producing bacteria using an antilipase antibody affected several lipase-producing bacteria, including B. fibrisolvens, and decreased BH in vitro (Edwards et al 2017).…”

Effect of Broussonetia papyrifera L. silage on blood biochemical parameters, growth performance, meat amino acids and fatty acids compositions in beef cattle

“…Ruminant products have higher saturated fatty acids (SFA) compared with nonruminants, mainly because of hydrogenation of dietary unsaturated fatty acids by ruminal microbes [1]. Feeding strategies have been developed to increase the unsaturated fatty acids of ruminants' products by increasing the rumen bypass unsaturated fatty acids or decreasing ruminal hydrogenation of dietary unsaturated fatty acids [2]. For ruminants, there are great opportunities to explore the potential of additional forages in their diets.…”

State of the art in rumen lipid protection technologies and emerging interfacial protein cross‐linking methods

“…A new approach to prevent ruminal BH of PUFA, based on the application of esterase inhibitors, has been suggested by Sargolzehi et al . They demonstrated the potential of pyridostigmine bromide, a acetylcholine esterase inhibitor, to reduce rumen lipolytic activity, as no BH of C18:2 n‐6 was observed after 6 h in vitro incubation.…”