Effects of emulsifier charge and concentration on pancreatic lipolysis. 1. in the absence of bile salts

Research output: Contribution to journalArticlepeer-review

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Effects of emulsifier charge and concentration on pancreatic lipolysis. 1. in the absence of bile salts. / Vinarov, Zahari; Petkova, Yana; Tcholakova, Slavka; Denkov, Nikolai; Stoyanov, Simeon; Pelan, Edward; Lips, Alex.

In: Langmuir, Vol. 28, No. 21, 29.05.2012, p. 8127-8139.

Research output: Contribution to journalArticlepeer-review

Harvard

Vinarov, Z, Petkova, Y, Tcholakova, S, Denkov, N, Stoyanov, S, Pelan, E & Lips, A 2012, 'Effects of emulsifier charge and concentration on pancreatic lipolysis. 1. in the absence of bile salts', Langmuir, vol. 28, no. 21, pp. 8127-8139. https://doi.org/10.1021/la300366m

APA

Vinarov, Z., Petkova, Y., Tcholakova, S., Denkov, N., Stoyanov, S., Pelan, E., & Lips, A. (2012). Effects of emulsifier charge and concentration on pancreatic lipolysis. 1. in the absence of bile salts. Langmuir, 28(21), 8127-8139. https://doi.org/10.1021/la300366m

Vancouver

Author

Vinarov, Zahari ; Petkova, Yana ; Tcholakova, Slavka ; Denkov, Nikolai ; Stoyanov, Simeon ; Pelan, Edward ; Lips, Alex. / Effects of emulsifier charge and concentration on pancreatic lipolysis. 1. in the absence of bile salts. In: Langmuir. 2012 ; Vol. 28, No. 21. pp. 8127-8139.

Bibtex

@article{9b1d9faa61c94d34b4f145d946276467,
title = "Effects of emulsifier charge and concentration on pancreatic lipolysis. 1. in the absence of bile salts",
abstract = "An in vitro study is performed with sunflower oil-in-water emulsions to clarify the effects of type of used emulsifier, its concentration, and reaction time on the degree of oil lipolysis, α. Anionic, nonionic, and cationic surfactants are studied as emulsifiers. For all systems, three regions are observed when surfactant concentration is scaled with the critical micelle concentration, C S/cmc: (1) At C S < cmc, α ≈ 0.5 after 30 min and increases up to 0.9 after 4 h. (2) At C S ≈ 3 × cmc, α ≈ 0.15 after 30 min and increases steeply up to 0.9 after 2 h for the cationic and nonionic surfactants, whereas it remains around 0.2 for the anionic surfactants. (3) At C S above certain threshold value, α = 0 for all studied surfactants, for reaction time up to 8 h. Additional experiments show that the lipase hydrolyzes molecularly soluble substrate (tributirin) at C S ≫ cmc, which is a proof that these surfactants do not denature or block the enzyme active center. Thus, we conclude that the mechanism of enzyme inhibition by these surfactants is the formation of a dense adsorption layer on an oil drop surface, which displaces the lipase from direct contact with the triglycerides.",
author = "Zahari Vinarov and Yana Petkova and Slavka Tcholakova and Nikolai Denkov and Simeon Stoyanov and Edward Pelan and Alex Lips",
year = "2012",
month = may,
day = "29",
doi = "10.1021/la300366m",
language = "English",
volume = "28",
pages = "8127--8139",
journal = "Langmuir",
issn = "0743-7463",
publisher = "American Chemical Society",
number = "21",

}

RIS

TY - JOUR

T1 - Effects of emulsifier charge and concentration on pancreatic lipolysis. 1. in the absence of bile salts

AU - Vinarov, Zahari

AU - Petkova, Yana

AU - Tcholakova, Slavka

AU - Denkov, Nikolai

AU - Stoyanov, Simeon

AU - Pelan, Edward

AU - Lips, Alex

PY - 2012/5/29

Y1 - 2012/5/29

N2 - An in vitro study is performed with sunflower oil-in-water emulsions to clarify the effects of type of used emulsifier, its concentration, and reaction time on the degree of oil lipolysis, α. Anionic, nonionic, and cationic surfactants are studied as emulsifiers. For all systems, three regions are observed when surfactant concentration is scaled with the critical micelle concentration, C S/cmc: (1) At C S < cmc, α ≈ 0.5 after 30 min and increases up to 0.9 after 4 h. (2) At C S ≈ 3 × cmc, α ≈ 0.15 after 30 min and increases steeply up to 0.9 after 2 h for the cationic and nonionic surfactants, whereas it remains around 0.2 for the anionic surfactants. (3) At C S above certain threshold value, α = 0 for all studied surfactants, for reaction time up to 8 h. Additional experiments show that the lipase hydrolyzes molecularly soluble substrate (tributirin) at C S ≫ cmc, which is a proof that these surfactants do not denature or block the enzyme active center. Thus, we conclude that the mechanism of enzyme inhibition by these surfactants is the formation of a dense adsorption layer on an oil drop surface, which displaces the lipase from direct contact with the triglycerides.

AB - An in vitro study is performed with sunflower oil-in-water emulsions to clarify the effects of type of used emulsifier, its concentration, and reaction time on the degree of oil lipolysis, α. Anionic, nonionic, and cationic surfactants are studied as emulsifiers. For all systems, three regions are observed when surfactant concentration is scaled with the critical micelle concentration, C S/cmc: (1) At C S < cmc, α ≈ 0.5 after 30 min and increases up to 0.9 after 4 h. (2) At C S ≈ 3 × cmc, α ≈ 0.15 after 30 min and increases steeply up to 0.9 after 2 h for the cationic and nonionic surfactants, whereas it remains around 0.2 for the anionic surfactants. (3) At C S above certain threshold value, α = 0 for all studied surfactants, for reaction time up to 8 h. Additional experiments show that the lipase hydrolyzes molecularly soluble substrate (tributirin) at C S ≫ cmc, which is a proof that these surfactants do not denature or block the enzyme active center. Thus, we conclude that the mechanism of enzyme inhibition by these surfactants is the formation of a dense adsorption layer on an oil drop surface, which displaces the lipase from direct contact with the triglycerides.

UR - http://www.scopus.com/inward/record.url?scp=84861581391&partnerID=8YFLogxK

U2 - 10.1021/la300366m

DO - 10.1021/la300366m

M3 - Article

C2 - 22554275

AN - SCOPUS:84861581391

VL - 28

SP - 8127

EP - 8139

JO - Langmuir

JF - Langmuir

SN - 0743-7463

IS - 21

ER -