title: Chemometric and conformational approach to the analysis of the aggregation capabilities in a set of bile salts of the allo and normal series.
abstract: Bile salts are steroid biosurfactants that have a significant role in fat digestion, cholesterol micellar solubilization, and regulation of metabolism. They are important in pharmaceutical studies as modulators of the transport-permeability of drugs or as ligands for certain receptors. For the rational application of bile salts in medicine, it is necessary to have detailed knowledge of their aggregation capabilities (which determine their membranotoxicity and solubilization capacity). From the examination of bile salt derivatives, the in plane of lnk (RPHPLC) and micelle aggregation number n, as well as the anion of 7-oxodeoxycholic acid (7-OxD) and anion of cholic acid (C), are considered to be outliers, related to linear hydrophobic congeneric groups, which means that their micelles, in addition to being determined by hydrophobic interactions, are determined by hydrogen bonds, i.e., they form micelles with higher aggregation numbers than would be expected from the hydrophobicity of their steroid skeleton. For bile salts of the normal series in the formation of hydrogen bonds in secondary micelles, the crucial structural elements of the steroid skeleton are: α-equatorial-C3-OH group and α-axial-C12-OH group. Bile salts of the allo series, including allocholic (aC), allodeoxycholic (aDC) and allochenodeoxycholic acid (aCD), belong to the linear hydrophobic congeneric group. Their micelles are determined by hydrophobic interactions. It is assumed that for the analyzed allo derivatives, the A ring of the steroid skeleton is in the twisted boat conformation, which explains the spatial sheltering of their C3-OH group in micelles.
authors.affiliation: University of Novi Sad, Faculty of Medicine, Department of Pharmacy, Hajduk Veljkova 3, 21000 Novi Sad, Serbia. Electronic address: mihaljp@uns.ac.rs.
authors.forename: Mihalj
authors.initials: M
authors.lastname: Poša
authors.affiliation: University of Novi Sad, Faculty of Medicine, Department of Pharmacy, Hajduk Veljkova 3, 21000 Novi Sad, Serbia.
authors.forename: Ana
authors.initials: A
authors.lastname: Sebenji
mesh_terms: D001647:Bile Acids and Salts / Q000737:chemistry*; D002784:Cholesterol / Q000737:chemistry; D019826:Cholic Acid / Q000737:chemistry; D002793:Cholic Acids / Q000737:chemistry; D003840:Deoxycholic Acid / Q000031:analogs & derivatives / Q000737:chemistry; D006860:Hydrogen Bonding; D057927:Hydrophobic and Hydrophilic Interactions; D008823:Micelles; D008968:Molecular Conformation; D013256:Steroids / Q000737:chemistry
chemical_list: D001647:Bile Acids and Salts; D002793:Cholic Acids; D008823:Micelles; D013256:Steroids; D003840:Deoxycholic Acid; C023867:7-ketodeoxycholic acid; C002001:allocholic acid; D002784:Cholesterol; D019826:Cholic Acid
keywords: Aggregation number; Critical micelle concentration; Linear congeneric group; Steroid skeleton