Preparation And Characterization Of Maltotriose And Sucrose Fatty Acid Esters

Sugar esters(SE)are non-ionic surfactants with good bacteriostasis,biodegradability and other effects,they have been widely used in food,medicine,cosmetics industries.Although there are several research on SE,their structure-property profile and new functional characteristics remain still unclear.In this research,enzymatic synthetic method was employed to prepare a seires of maltotriose and sucrose monoesters,the properties of the resulting SEs were evaluated in-depth.The main research outcomes derived from current work are as follows:(1)An homologous series of 6″-O-acylmaltotriose monoesters with alkyl side chains of different lengths(C10:0–C18:0)and saturations(C18:0 and C18:1)were synthesized by enzymatic method,and their interfacial and emulsifying properties,biological activities as well as mechanism of action were revealed.It was found that the functional properties of the ensuing maltotriose monoesters are closely related to the structures of hydrophobic alkyl side chains.Withthe increase of alkyl side chain length,the maltotriose monoesters exhibited superior interfacial emulsifying properties.The inhibitory potencies of maltotriose monoesters against RAW264.7 (murine macrophage),SH-SY5Y(human neuroblastoma cell line),MCF-7(human breast cancer cell line),HEPG2(human hepatoma cell line)and AC16(human cardiomyocyte cell line)showed that monoesters had shorter acyl chain(C12:0,C14:0;MD,ML)had no significant inhibitory effect on these five cell lines,while the longer chain homologues(C16:0,C18:0,C18:1;MP,MS, MO)showed moderate inhibitory effect on cell proliferation.The evaluation of the mechanism of action showed that stearoyl maltotriose(MS)was shown to significantly inhibit the proliferation of MCF-7 breast cancer cells by inducing G1 phase arrest.Specifically,the levels of the G1 phase-related markers cyclin D1 and cyclin E as well as the cycle-dependent kinase 4 were suppressed by this particular ester.This study revealed the structural-activity relationship of maltotriose monoesters,which provided theoretical basis for their development as food emulsifiers,antibacterial agents or pharmaceutical materials.(2)An homologous series of 6-O-acylsucrose monoesters with long-(C12:0–C18:0,C18:1)and very-long-chain(C20:0,C22:0,C22:1)fatty acid alkyl groups were synthesized by enzymatic means and their interfacial,foaming and emulsifying properties as well as biological activities were evaluated in detail.The results showed that the functional properties of sucrose monoesters were significantly related to the length of hydrophobic alkyl side chains.With the increase of acyl side chain length,the interfacial activity of those sucrose monoesters increased and their water solubility decreased.The foaming and emulsifying properties showed an inverted "V" trend,among which myristoylsucrose(C14:0,SM)exhibited the best foaming performance,stearoylsucrose(C18:0,SS)and oleoylsucrose(C18:1,SO)showed the most excellent emulsifying potencies.All the eight sucrose monoesters showed significant inhibitory effect on Gram-positive bacteria at low concentrations,however,they showed different inhibitory effects against Gramnegative bacteria and fungi at high concentrations.Six human cancer cell lines,including HEK-293(human embryonic kidney cell),NCI-H226(lung squamous cell carcinoma cell),MCF-7(breast cancer cell),SW480(colon cancer cell),RPMI 8226(multiple myeloma cell)and Sup T1(lymphoma cell),were selected to evaluation the anti-proliferative activities of the ensuing sucrose monoesters.Experiments showed that certain sucrose monoesters possess moderate antitumor activities.The study elucidated the structure-property profile of sucrose monoesters,which can be helpful to expand the application of such esters in food,pharmaceutical and cosmetic industries.