Cholesterol Adsorption Capacity Research Articles

Comparison of structural, functional and in vitro digestion properties of bread incorporated with grapefruit peel soluble dietary fibers prepared by three microwave-assisted modifications.

In our previous study, three kinds of grapefruit peel soluble dietary fibers (SDFs) were prepared by microwave-assisted modifications, including microwave-sodium hydroxide treatment SDF (MST-SDF), microwave-enzymatic treatment SDF (MET-SDF) and microwave-ultrasonic treatment SDF (MUT-SDF). The present study aimed to investigate the structural, functional and in vitro digestion properties of three kinds of bread incorporated with SDFs, named MST-SDF bread (SB), MET-SDF bread (EB), and MUT-SDF bread (UB). Scanning electron microscopy, X-ray diffraction, differential scanning calorimetry and texture profile analysis were used to determine the structural properties. In comparison with the SB and EB, the UB showed an ideal hardness and internal structure, and also significant improvement of the thermal stability. Meanwhile, the UB exhibited the highest overall acceptability in the sensory evaluation. In addition, the water holding capacity (WHC), cholesterol adsorption capacity (CAC) and nitrite ion adsorption capacity (NIAC) of UB were superior to those of the other two samples. Moreover, the in vitro digestive glucose release rates of breads were all significantly reduced by the addition of SDFs, especially that of UB. In summary, the present study showed that UB presented the best performance in terms of structural, functional and in vitro digestion properties, implying that MUT-SDF could be utilized in bread with high quality and low glucose release rate, and developed as a potential ingredient of functional food.

Microwave assisted extraction with three modifications on structural and functional properties of soluble dietary fibers from grapefruit peel

Microwave-sodium hydroxide treatment (MST), microwave-enzymatic treatment (MET) and microwave-ultrasonic treatment (MUT) were used to treat grapefruit peel, then the structural and functional properties of extracted soluble dietary fibers (SDF), named as MST-SDF, MET-SDF and MUT-SDF, were investigated. The scanning electron microscopy, molecular weight, X-ray diffraction, FT-IR, thermal properties and monosaccharide composition were used to determine the structural properties. Compared to the grapefruit peel SDF without treatment (WT-SDF) and pure microwave treatment (PMT-SDF), MST-SDF, MET-SDF and MUT-SDF showed a more complex and loose structure. Moreover, they possessed higher molecular weight, crystallinity and thermal stability, and more diverse monosaccharide composition. In addition, functional properties, including water holding capacity (WHC), oil holding capacity (OHC), cholesterol adsorption capacity (CAC), glucose adsorption capacity (GAC) and nitrite ion adsorption capacity (NIAC), were enhanced by the three different modification methods. Especially, MUT-SDF showed the highest WHC, OHC, CAC, GAC and NIAC as compared with the other samples. In summary, the present study suggested that the MUT could be used as the ideal modification method for grapefruit peel SDF, and MUT-SDF has great potential for the application in functional food industry.

In vitro investigation of the influence of nano-fibrillated cellulose on lipid digestion and absorption

Nanocellulose, including nano-fibrillated cellulose (NFC), has been a topic of significant interest and a number of studies have focused on using it for the fabrication of stable oil-in-water emulsions. However, limited studies have been performed to understand the potential influence of NFC on lipid digestion and absorption. In this study, a simulated digestion model, consisting of salivary, gastric and intestinal digestion phases, was used to investigate the effects of NFC on lipid digestion and absorption. To better understand the mechanisms behind, the effects of NFC on lipase activity, micellar solubility of cholesterol and bile acid diffusion were studied in addition to the cholesterol adsorption capacity of NFC, with conventional cellulose as a comparison. Results showed that NFC slightly reduced lipase activity, but NFC or cellulose at concentrations up to 1.1% (w/w) did not significantly influence lipid digestion under simulated intestinal conditions. Moreover, NFC showed greater bile acid retardation effect than cellulose, and slightly higher cholesterol adsorption capacity probably due to its larger specific surface area. Nonetheless, NFC did not significantly affect micellar solubility of cholesterol. These results suggest that NFC, when added into fat-rich foods, may have health benefits via its viscosity effect and retardation effect on bile acid absorption.

Modification of carrot (Daucus carota Linn. var. Sativa Hoffm.) pomace insoluble dietary fiber with complex enzyme method, ultrafine comminution, and high hydrostatic pressure

Insoluble dietary fiber (DF) extracted from carrot pomace was modified by complex enzyme method, ultrafine comminution and high hydrostatic pressure and their structural, physicochemical, and functional properties were evaluated. Results showed that complex enzyme method increased the content of soluble DF to 15.07%, and the cholesterol adsorption capacity peaked; ultrafine comminution greatly improved the total antioxidant activities, DPPH radical scavenging capacity and antioxidant abilities in linoleic acid system of DF; high hydrostatic pressure led to a significant increase in capacities of water retention (7.14 g/g, 600 MPa), water swelling (10.02 mL/g, 500 MPa), oil retention (2.35 g/g, 500 MPa), cation exchange (2.29 mmol/g, 600 MPa), and glucose adsorption (2.634 mmol/g, 400 MPa). Furthermore, SEM showed that surface structures of all modified DF were loose. Overall, three kinds of modification methods have shown their respective advantages. Modified DF from carrot pomace can be applied as a functional ingredient in diverse food products.

Modification of bamboo shoot dietary fiber by extrusion-cellulase technology and its properties

ABSTRACTIn this study, the effects of extrusion combined with cellulase on the structural, physicochemical, and functional properties of bamboo shoots dietary fiber were evaluated. Extrusion-cellulase treatment increased the contents of soluble dietary fiber (22.17 g/100 g dry solids). The scanning electron microscopy and Fourier transformed infrared spectroscopy analyses showed that the extrusion-cellulase treatment altered the structure of bamboo shoots dietary fiber without destroying the main components. Bamboo shoots dietary fiber modified by extrusion-cellulase treatment showed improved water-holding capacity (9.34 g/g dry solids), oil-holding capacity (10.74 g/g dry solids), swelling capacity (8.32 mL/g dry solids), cation exchange capacity and functional properties, including glucose adsorption capacity (158 mg/g dry solids), cholesterol adsorption capacity (9.8 mg/g dry solids (pH 2), and 11.4 mg/g dry solids (pH 7)), and nitrite ion adsorption capacity (29 μg/g dry solids (pH 2) and 21 μg/g dry solids (pH 7)). This experiment provided a theoretical basis for the modification of bamboo shoots dietary fiber, and the bamboo shoots dietary fiber modified by extrusion-cellulase can be useful as a fiber-rich ingredient in functional foods.

Cholesterol imprinted composite membranes for selective cholesterol recognition from intestinal mimicking solution

Molecularly imprinted polymers which have been extensively investigated as selective adsorbents were constructed using a template molecule during the polymerization to gain template-specific cavities. In this study, we prepared cholesterol imprinted poly(2-hydroxyethyl methacrylate-methacryloyamidotryptophan) (PHEMA-MTrp) particles embedded composite membranes. These membranes were characterized through elemental analysis, FTIR, SEM, swelling tests, and surface area measurements. Adsorption experiments were performed in a batch experimental set-up, and the adsorption medium was either a methanol or intestinal-mimicking solution. Stigmasterol and estradiol were used as competing molecules in selectivity tests. Some results are as follows: the specific surface areas of MIP particle-embedded membranes, NIP particle-embedded membranes, and membranes without particles were 36.5, 29.2 and 13.7 m2/g, respectively. The imprinted membranes were 1.96 and 2.13 times more selective for cholesterol when compared to stigmasterol and estradiol used as competitor agents, respectively. Cholesterol adsorption capacity increased up to 23.43 mg/g with increasing cholesterol concentration of 2 mg/mL. The MIP particle-embedded composite membranes showed a negligible loss in cholesterol adsorption capacity after ten consecutive adsorption cycles using the same adsorbent.

Dietary fibre and phenolic-rich extracts from Musa paradisiaca inflorescence ameliorates type 2 diabetes and associated cardiovascular risks

The present study investigated nutraceutical properties of Musa paradisiaca (Nendran variety) inflorescence (PI). PI was found to be a rich source of soluble (SDF) and insoluble dietary fibre (12.45 and 53.31% respectively). SDF exhibited potential glucose and cholesterol adsorption capacity. Ethyl acetate (PIE) and methanol (PIM) extracts of PI were analyzed for phenolics content, antioxidant activities, antidiabetic and cardiovascular protection efficacy. PIM exhibited significant ABTS free radical scavenging activity (IC50-57.2±1.15μg/mL) and inhibited the production of reactive oxygen species in L6 myoblasts in a dose-dependent manner. PIM also demonstrated potential inhibition of carbohydrate digestive enzymes (α-amylase and α-glucosidase), interfered with the production of glycated end products (IC50-142.27±1.09μg/mL) and enhanced glucose uptake in L6 myoblasts. PIM inhibited LDL oxidation (IC50-169.52±1.77μg/mL) and ACE, indicating its protective role against cardiovascular risk factors. The study demonstrated the nutraceutical potential of PI in ameliorating type 2 diabetes and associated cardiovascular problems.

Properties of Dietary Fibers from Agroindustrial Coproducts as Source for Fiber-Enriched Foods

The importance of food fibers has led to the development of a large and potential market for fiber-enriched foods, and nowadays, there is an ongoing interest to find new sources of dietary fiber (DF), such as agroindustrial coproducts which have traditionally been undervalued. The aim of the article was to evaluate the suitability of five sources of DF to develop fiber-enriched foods. Proximate analysis and physicochemical, technological, and physiological properties (including cholesterol absorption capacity) of these DF sources were determined and compared. Not only proximate composition but also physicochemical and techno-functional properties of DF samples depend on the composition of the raw material (pomegranate, citrus, tiger nuts…), the industrial source, and the coproducts processing into DF extracts. Total dietary fiber content and the ratio insoluble/soluble dietary fiber determine the values obtained for these properties. However, cholesterol adsorption capacity seems to be influenced for other components linked to dietary fiber. Extracts rich in DF obtained from agroindustrial coproducts can be used as functional ingredients. The characterization of these extracts is very important to decide in which type of foods these fibers could be added without causing adverse changes in the food matrix. Pomegranate dietary fiber shows promising results principally about their cholesterol adsorption capacity which must be investigated in in vitro digestion process.

Cholesterol removal onto the different hydrophobic nanospheres: A comparison study

The aim of this study is to prepare two different hydrophobic polymeric nanospheres for cholesterol removal. Poly(HEMA–MAT) nanospheres with an average size of 100nm and poly(HEMA–MAP) nanospheres with an average size of 158nm were produced by surfactant free emulsion polymerization of HEMA and MAT and MAP monomers. These hydrophobic nanospheres were characterized by FTIR, SEM, elemental analysis, particle size and surface area measurements. Cholesterol removal experiments were performed in a batch experimental set-up and removal medium was methanol. Cholesterol adsorption capacity of poly(HEMA–MAP) nanospheres was approximately three times higher than that of poly(HEMA–MAT) nanospheres.

고추씨 에탄올 추출물이 콜레스테롤 흡착능 및 UDP-glucuronyl transferase 활성에 미치는 영향

본 연구에서는 고추씨 에탄올추출물이 콜레스테롤 흡착능 및 UDP-glucuronyl transferase 활성에 미치는 영향을 관찰하였다. In vitro 콜레스테롤 흡착능에서는 대조군에 비해 고추씨 에탄올추출물 모든 농도에서 유의적으로 증가하였다. In vivo에서 실험동물은 체중 <TEX>$100{\pm}10$</TEX> g 내외의 Sprague-Dawley계 수컷 흰쥐를 사용하였으며, 실험군은 정상식이를 공급한 정상군과 고지방 고콜레스테롤 식이 실험군으로 나누고 고지방 고콜레스테롤 실험군을 다시 고추씨 에탄올추출물을 공급하지 않은 군(HF groups), 0.1% 공급한 군(HEA group), 0.2%을 공급한 군(HEB group) 및 0.5%을 공급한 군(HEC group), 5군으로 나누고 각 군당 8마리씩 3주간 사육하였다. 체중증가량은 정상군에 비해 HF 군에서 유의적으로 증가하였고 고추씨 에탄올추출물을 공급한 모든 군에서 HF 군에 감소하였으나 유의적인 차이는 없었다. 식이효율은 고추씨 에탄올추출물을 각각 0.1%, 0.2% 및 0.5% 공급한 군에서는 HF군에 비해 유의적이지는 않았지만 감소하는 경향을 보였다. 간조직의 총콜레스테롤 및 중성지질 함량은 정상군에 비해 HF 군에서 유의적으로 증가하였고 HF 군에 비해 HEA, HEB 및 HEC군에서는 유의적이지는 않았지만 다소 감소하는 경향을 나타내었다. UDP-glucuronyl transferase 활성에서는 정상군에 비해 HF 군에서 증가되었고, 고추씨 에탄올추출물 공급군인 HEC 군에서는 HF 군에 비해 유의적으로 증가되어 가장 높은 활성을 나타내었다. 혈청중의 총콜레스테롤 및 중성지방 농도는 정상군에 비해 HF 군에서 유의적으로 증가하였고, HEA, HEB 및 HEC 군에서 HF 군에 비해 감소하였다. HDL-콜레스테롤은 정상군에 비해 HF 군에서 유의적으로 감소하였으나 HEA, HEB 및 HEC 군에서는 HF 군에 비해 정상군 수준으로 증가하는 경향을 보였다. 반면, LDL-콜레스테롤은 HF 군에서 정상군에 비해 유의적으로 증가하였으나 HEA, HEB 및 HEC 군에서는 모두 유의적 감소를 나타내었다. 대변중의 총콜레스테롤 함량은 정상군에 비해 HF 군에서 유의적으로 증가하였고 HF 군에 비해 특히 고추씨 에탄올추출물 공급군 HEB 군 및 HEC 군에서 증가하는 경향을 나타내었으나 유의적인 차이는 없었다. 중성지질 함량은 정상군에 비해 HF 군에서는 유의적이지는 않았지만 증가되었고, 고추씨 에탄올추출물을 공급한 HEB군 및 HEC 군에서 HF 군에 비해 다소 증가하는 경향을 나타내었다. 따라서 고추씨 에탄올 추출물은 콜레스테롤 흡착능에서 효과적으로 작용하였으며 고지방 고콜레스테롤 식이 흰쥐의 UDP-glucuronyl transferase 활성 및 지질대사에 효과적으로 작용하였음을 규명하였다. The purpose of this study was to investigate the effects of ethanol extracts from red pepper seeds on cholesterol adsorption capacity and UDP-glucuronyl transferase activity. In vitro cholesterol adsorption capacity of 2%, 5% and 10% ethanol extracts from red pepper seed groups were significantly higher than that of the control group. Sprague-Dawley strain male rats weighing <TEX>$100{\pm}10$</TEX> g were randomly assigned to one normal diet N group and experimental groups fed high fat and high cholesterol diet, which were divided into HF (0.0%), HEA (0.1%), HEB (0.2%), and HEC (0.5%) groups according to the amount of ethanol extracts from red pepper seeds added to their basal diet. The body weight gain in the HF group was higher than that in the N group, and those in the HEA, HEB and HEC groups were lower than that in the HF group However, there were no statistically significant differences among the all the groups. The hepatic triglyceride and total cholesterol contents in the N group was significantly lower than that in the HF group, and those in the HEA, HEB and HEC groups were lower than that in the HF group. The hepatic UDP-glucuronyl transferase activity in the N group was lower than that of the HF group and those in the HEA, HEB and HEC groups were lower than that of the HF group. The serum total cholesterol and triglyceride contents of the HF group were significantly higher than that of the N group, and those of the HEA, HEB and HEC groups were lower than that of the HF group. The serum HDL-cholesterol contents in all groups supplemented with the ethanol extracts from red pepper seeds were significantly higher than that of the HF group. The serum LDL-cholesterol contents of the HF group were significantly higher than that of the N group, and those of the HEA, HEB and HEC groups were lower than that of the HF group. The fecal total cholesterol contents were significantly higher in the HF group compared to the N group, and those of the HEB and HEC groups were lower than that of the HF group. The fecal triglyceride contents in the N group was higher than that of the HF group, and those of the HEA, HEB and HEC groups were lower than that of the HF group. This study suggested that the ethanol extracts from red pepper seeds have powerful health benefits by the UDP-glucuronyl transferase activity and lipid metabolism.

Synthesis of cholesterol imprinted polymeric particles

The aim of this study is to prepare cholesterol-imprinted polymeric particles. N-Methacryloyl-( l)-tyrosinemethylester (MAT) was chosen as the complexing monomer. In the first step, functional monomer MAT was synthesized by the reaction of l-tyrosine methylester and methacryloyl chloride and characterized by FTIR and NMR. Then, cholesterol was complexed with MAT in different mol ratios and the cholesterol-imprinted poly(2-hydroxyethyl methacrylate- N-methacryloyl-( l)-tyrosine methylester) [MIP] particles were synthesized by bulk polymerization. After that, the template molecules (i.e., cholesterol) were removed using chloroform. MIP particles were characterized by elemental analysis, FTIR, SEM, swelling tests and surface area measurements. Cholesterol adsorption experiments were performed in a batch experimental set-up. Adsorption medium was methanol or intestinal mimicking solution. Stigmasterol and estradiol were used as competing molecules in selectivity tests. Obtained results were as follows: swelling ratio of MIP and non-imprinted (NIP) particles were 60.8% and 44.1% in water. With the increase in the amount of MAT in the polymerization medium, incorporation of MAT was increased (16.6–78.0 μmol/g). SEM photographs showed the surface roughness and porosity. Specific surface area of NIP and MIP particles were found as 19.2 and 31.5 m 2/g, respectively. Template molecules (i.e., cholesterol) were removed from the polymer structure in the ratio of 76–84% of the initial concentration. Cholesterol adsorption increased with the increase in cholesterol concentration up to 1.5 mg/mL. MIP particles prepared using higher amounts of cholesterol exhibit significantly higher capacity to the NIP particles (i.e., control polymer). MIP particles were 3.09 and 3.60 times selective with respect to the stigmasterol and estradiol, respectively. Reusability of MIP particles was also investigated. MIP particles showed negligible loss in the cholesterol adsorption capacity after five adsorption–desorption cycles with the same adsorbent.