Comparison of the effects of high- and low-methoxyl pectins on blood and faecal lipids in man

Abstract

1, The effects on blood and faecal lipids of the addition of 15 g of either high-or low-methoxyl pectin to the habitual diets of ten healthy young adults have been studied.2. Serum total cholesterol levels were reduced by a mean of 16% during consumption of low-methoxyl pectin and 18% during consumption of high-methoxyl pectin. High density lipoprotein cholesterol levels and triglyceride levels were unchanged.3. There was no difference in faecal fat and steroid excretion between the two pectins. 4.The results suggest that it is the gel-forming properties of the pectins which are important in the cholesterol-lowering effect rather than differences in bile acid binding due to different methoxyl contents.Pectins are polygalacturonic acid polymers, occurring naturally in plant cell-walls, and are part of the dietary fibre complex. The carboxyl groups of the constituent galacturonic acid molecules are esterified to varying extents, usually with methanol (Rees, 1967) and pectins can be described as high-or low-methoxyl (HMP and LMP respectively), the latter having less than 50% of possible carboxyl groups esterified (Kertesz, 1963).The plasma cholesterol-lowering effects of pectin in man have been investigated in at least eleven studies, summarized by Kay et al. (1978). In all but the studies of Delbarre et al. (1977) and Fahrenbach et al. (1965), where daily doses of polymer were low (6 g/d in each instance), pectin has been shown to reduce plasma cholesterol levels.The type of pectin used in most experiments has been described as 'Pectin NF' a relatively high-methoxyl product with 65-75 % of possible carboxyl groups esterified (American National Formulary XIII, 1970). The exception was the work of Delbarre et al. '1977) where neither lemon pectin (approximately 40% esterified) nor apple pectin (degree of methoxylation 70%) was effective at a dose of 6 g/d. Studies in rats have suggested that only pectins with a high-methoxyl content are effective plasma cholesterol-lowering agents (Ershoff & Wells, 1962;Mokady, 1973). However, we have demonstrated a significant cholesterol-lowering effect for LMP in animal studies (Judd et al. 1977). In the study by Ershoff & Wells (1962) cholesterol levels of rats given 50 g LMP/kg were lower than controls, although this did not reach statistical significance. Similarly, in the study by Mokady (1973), there was no difference between the cholesterol levels of rats given pectins with approximately 26 and 49% of possible carboxyl groups esterified. The only significant reduction was achieved with a pectin of 51 % esterification.Durrington e f al. (1976) and Kay & Truswell(l977) have also suggested that the methoxyl content of pectins may determine, in part, their effectiveness as cholesterol-lowering agents, but the latter workers also suggested that the viscosity of pectin and the form in which it is fed are more important.The present experiment was therefore designed to compare the effect of HMP and LMP on blood and faecal lipids in healthy adults, in order to assess the usefuln...

Fermentation Patterns of Various Pectin Sources by Human Fecal Microbiota

“…Citrus pectin sources (high DM and high MW) exerted greater LDL cholesterol-lowering properties than low DM and low MW of citrus pectin and high DM of orange pulp fiber [29]. However, Judd and Truswell [30] reported that LMP has similar cholesterol-lowering effects compared to HMP. Wet and dry weights of feces were higher on HMP, while gut transit time and fecal water were similar in both groups (HMP and LMP).…”

Efeito de diferentes tipos de fibras sobre frações lipídicas do sangue e fígado de ratos wistar

“…Alguns mecanismos são propostos para explicar a ação das fibras solúveis na redução dos níveis de colesterol sérico e um deles é baseado na propriedade das fibras solúveis em hidratar-se no meio aquoso do intestino delgado, formando géis caracterizados por ligações cruzadas com os sais biliares, reduzindo o colesterol sérico, uma vez que o colesterol é usado para o reabastecimento de sais biliares no organismo (Judd & Truswell, 1982;Eastwood, 1992;Melo et al, 2007).…”

Dietary approaches for management of cardio-vascular health- a review

“…Oat gum and Guar gum were slightly less effective and decreased serum cholesterol by approximately 22%, compared with values for cellulose-fed rats. Pectin has been reported to have a wide range of effects, depending on molecular weight and degree of methoxylation (Ebihara et al 1979;Judd and Truswell 1982), whereas oat bran and soy fibre produce modest effects (Anderson et al 1994;Anderson 1995). In humans, psyllium and guar gum are reported to be the most effective cholesterol-lowering soluble fibres (Anderson et al 1990).…”