The products from lipase-catalysed hydrolysis of bovine milkfat killHelicobacter pylori in vitro

Abstract

Free fatty acids and monoglycerides released from milkfat by partial pregastric lipase-catalysed hydrolysis are bactericidal towards Helicobacter pylori. Two milkfat preparations were investigated: a normal bovine milkfat, and a fractionated milkfat preparation, termed ModFat, enriched in triglycerides containing short-and medium-chain fatty acids. The released products were tested for bactericidal potency against H. pylori. The potencies of the respective preparations were consistent with expected potencies calculated from individual free fatty acid and monoglyceride concentrations and their lauric acid equivalence factors (K i ). ModFat products were more bactericidal, in accordance with release of free fatty acid types of high potency, and addition of the surfactant Tween 80 to the hydrolysed lipid increased potency eight times more than did addition of lecithin. Tween 80 micelles have smaller aggregation numbers, and the mixed micelles of Tween 80/free fatty acids would be more likely to expose the bacteria to higher apparent free fatty acid concentrations.

Milk intelligence: Mining milk for bioactive substances associated with human health

“…Analysis of the anti-microbial properties of bovine milk fat after partial hydrolysis by calf pregastric lipase demonstrated that lauric acid was most potent against the Grampositive enterococci, while caprylic acid (C8:0) was most potent against the Gram-negative coliforms (Sun, O'Connor, & Roberton, 2002). More recently, the products from lipase-catalysed hydrolysis of bovine milk fat were shown to kill H. pylori in vitro (Sun, O'Connor, MacGibbon, & Roberton, 2007).…”

Novel Antibacterial Proteins from the Microbial Communities Associated with the Sponge Cymbastela concentrica and the Green Alga Ulva australis

“…The mode of action is thought to be related to the detergent properties of these acids, which allow them to create pores or, at high concentrations, to cause cell lysis through cell wall degradation (12). Free fatty acids released through the actions of lipases have been shown to protect human skin against infection from opportunistic pathogens such as S. aureus (14) and to protect the gastrointestinal tract against pathogens such as Helicobacter pylori, Enterococcus faecalis, and Klebsiella pneumoniae (49,50). Lipases have also been associated with antibacterial activity in sand flies (4), suggesting a broad biological role for lipases in the protection against bacterial infection.…”

Nutrient Signaling: Evolutionary Origins of the Immune-Modulating Effects of Dietary Fat

“…However, some studies suggest that concentrations of lipids present in the gastrointestinal tract are sufficient to influence bacterial growth Sun et al 2007). For example, hydrolysis of milk fat by lipases yields FA and monoglycerides in millimolar (mM) concentrations in the stomach (3.35 mM and 12 mM) that are effective in killing bacteria such as Helicobacter pylori (Sun et al 2007). In the small intestine, the site of absorption of most dietary FA, triglycerides and free FA also have been measured in millimolar concentrations in the postprandial state (Di Maio and Carrier 2011); similar concentrations are bactericidal to a variety of gut pathogens (Sprong et al 2001).…”

“…However, some studies suggest that concentrations of lipids present in the gastrointestinal tract are sufficient to influence bacterial growth Sun et al 2007). For example, hydrolysis of milk fat by lipases yields FA and monoglycerides in millimolar (mM) concentrations in the stomach (3.35 mM and 12 mM) that are effective in killing bacteria such as Helicobacter pylori (Sun et al 2007).…”

“…Inhibition of pathogens by the products of digestion of dietary fat, particularly milk fat, has been demonstrated in mammalian herbivores (Cañas-Rodriguez and Smith 1966;Sun et al 2007) and in humans (Hamosh et al 1999;Isaacs 2001). Free FA and monoglycerides with strong antimicrobial activity are generated by the action of gastric lipases on milk fat when infants consume breast milk (Isaacs et al 1990).…”