Evaluation of the in vitro anti-atherogenic activities of goat milk and goat dairy products

Abstract

Given that goat milk and dairy products should be consumed daily according to suggestions based on Mediterranean diet, the current study evaluates the antiatherogenic properties of goat milk and goat dairy products (yogurt and white cheese). Total lipids (TLs) of all three samples were extracted by the method of Bligh and Dyer and further separated into total polar lipids (TPLs) and total neutral lipids (TNLs) by counter current distribution. The fatty acid profiles of TPL and TNL of all three samples were determined by gas chromatography analysis. TL and TPL were tested to determine whether they induce platelet aggregation or inhibit platelet aggregation induced by the platelet-activating factor (PAF). The most active lipids were found in goat white cheese (i.e., since they showed lower IC 50 values in both TL and TPL samples than corresponding fractions of goat milk and goat yogurt), so the TPL of goat white cheese were further separated by preparative thin-layer chromatography (TLC). The obtained polar lipid fractions after TLC separation were also tested for their biological activity. All the samples' lipids, and especially the polar ones, were found to exhibit strong anti-atherogenic activities. This fact highlights the nutritional value of goat dairy products in terms of cardioprotection, as PAF is a crucial inflammatory mediator that is implicated in the mechanism of atherogenesis.

Evaluation of sensory and in vitro anti-thrombotic properties of traditional Greek yogurts derived from different types of milk

“…2a and b, seven bands of polar lipid fractions have been found in both yogurt samples. These results correspond with previously published research on the lipid fractions obtained in goat cheese (Poutzalis et al, 2016). …”

“…The TNL fraction of goat yogurt was found to exhibit statistically higher levels ( p < 0.05) of caprylic acid (C8:0), capric (10:0), lauric (12:0), myristic (14:0), palmitic (16:0), oleic (18:1), linoleic (18:2) and α-linolenic (18:3) fatty acids in contrast to the TNL fractions of ewe and cow yogurts (Table 3). The rather low levels of fatty acids in the TNL and TPL fractions are in concurrence with similar work on the TPL and TNL of goat dairy products (Poutzalis et al, 2016). …”

“…A five-point calibration curve (given by the equation y = 0.00012x + 0.0167 with r = 0.99993) was prepared using five solutions of heptadecanoic (17:0) acid methyl ester and heneicosanoic (21:0) acid methyl ester in various ratios (Poutzalis et al, 2016). The ratio of the area of the analyte peak to that of the internal standard represented the y value in the above equation, and subsequently, the x value represents the analyte concentration of the fatty acid in the unknown mixture.…”

“…Milk and dairy products contain compounds that can inhibit PAF activity, acting as PAF- inhibitors. These dairy components are of particular nutritional merit because they impede platelet aggregation in arteries while at the same time they prevent atheromatosis development (Antonopoulou et al, 1996; Poutzalis et al, 2016; Tsorotioti et al, 2014). …”

Ovine and Caprine Lipids Promoting Cardiovascular Health in Milk and Its Derivatives

“…In particular, Greek style yogurts produced with caprine and ovine milk have demonstrated greater PAF inhibitory properties in comparison to bovine yogurts. Research in relation to the anti-PAF activities of dairy products has demonstrated that the fermentation of milk to yogurt and then to cheese induces greater anti-thrombotic activity against PAF [11,12]. We focus on the effect of lipolysis and on the role of starter cultures such as Streptococcus thermophilus and Lactobacillus delbrueckii subsp.…”