Physicochemical properties, antioxidant activities and in vitro sustained release behaviour of co-encapsulated liposomes as vehicle for vitamin E and ß-carotene.

BACKGROUND: In this study the potential of liposomes as a vitamin E (VE) and ß-carotene (ßC) delivery system was examined. The co-encapsulated liposomes of ßC and VE (L-VE-ßC) were prepared and characterized. Their antioxidant properties were evaluated by free radical scavenging activities of 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid (ABTS), hydroxyl radical and lipid peroxidation assay. The in vitro sustained release behaviour was then investigated and discussed. RESULTS: VE and ßC were co-encapsulated in liposomes with high encapsulation efficiency, up to 92.49% and 86.16% for ßC and VE, respectively. The antioxidant activities of L-VE-ßC samples were significantly higher than that of single loaded liposome. Among different ratios of VE/ßC, L-VE-ßC at 5:3 exhibited the highest radical scavenging rates, with 66.80%, 56.58% and 34.39% for DPPH, ABTS and OH radical, respectively. L-VE-ßC samples also had a good ability to inhibit lipid peroxidation, especially the sample with ratios of VE/ßC at 5:3 and 3:1. In simulated gastrointestinal release, L-VE-ßC exhibited an excellent sustained release behaviour in SGF with the accumulated rate at about 20%, while the release rate in SIF increased to over 80%, where they should be absorbed. The release kinetics analysis indicated that ßC was released in the Higuchi model in stomach, and the Korsmeyr-Peppas model in intestine. CONCLUSION: Compared to single loaded liposomes, the combined-loaded liposomes exhibited higher antioxidant activity and bioavailability, suggesting the potential applications in functional foods. © 2022 Society of Chemical Industry.

Effect of ß-sitosterol self-microemulsion and ß-sitosterol ester with linoleic acid on lipid-lowering in hyperlipidemic mice.

BACKGROUND: The hypolipidemic effect of phytosterols has been wildely recognized, but its application is limited due to its insolubility in water and low solubility in oil. In this study, ß-sitosterol ester with linoleic acids and ß-sitosterol self-microemulsions were prepared and their hypolipidemic effects on hyperlipidemia mice were studied. METHODS: Firstly, the mice were randomly divided into normal group and model group,they were fed with basic diet and high-fat diet for 70 days respectively. After high-fat model mice was successfully established, the model group was further divided into eight groups: HFD (high-fat diet feeding), SELA-TSO(8 ml/kg, SELA:700 mg/kg), TSO (8 ml/kg), SSSM (8 ml/kg,SS:700 mg/kg), NLSM (8 ml/kg), SSHT-TSO (8 ml/kg, SS: 700 mg/kg) and SS-TSO (8 ml/kg, SS: 700 mg/kg) groups, and treated with ß-sitosterol ester with linoleic acid, ß-sitosterol self-microemulsion, commercial ß-sitosterol health tablets and ß-sitosterol powder for 35 days, respectively, and blank control groups were established. At the end of the treatment period, the blood lipid level, tissues, cholesterol and lipids in feces of mice in each group were investigated. Statistical and analytical data with SPSS 17.0 Software,statistical significance was set at p* < 0.05 and p** < 0.01 levels . RESULTS: The order of lowering blood lipid effect is listed as: SSSM> SELA-TSO > SSHT-TSO > SS-TSO, which shows that ß-sitosterolself-microemulsion have the highest treatment effect among the experimental groups. CONCLUSIONS: In this study, a new formulation of ß-sitosterol was developed, and its hypolipidemic effect was investigated. The results showed that ß-sitosterol self-microemulsion has a good blood lipid lowering effect.

Protective Effect of Tea Saponins on Alcohol-Induced Gastric Mucosal Injury in Mice.

Excessive alcohol consumption harms the human body, particularly the digestive system, by causing damage to the gastric mucosa. Tea saponin is a natural active substance extracted from tea tree seeds that has gastroprotective potential against alcohol-induced mucosal damage. However, the protective mechanism of tea saponins is not fully understood. The current study aimed to explore the protective mechanism of tea saponins against alcohol-induced gastric mucosal injury in mice. Histopathological changes, immunohistochemistry, immunoblotting, and gastric mucosa-related cytokine levels were analyzed in three groups of male mice: model, control, and tea saponin-treated. Compared to the model group, the tea saponin group prominently ameliorated alcohol-induced gastric mucosal injury by improving cell necrosis, inflammatory cell infiltration, and edema. Downregulation of inflammation-related factors cluster of differentiation 68 (CD68), myeloperoxidase (MPO), tumor necrosis factor-α (TNF-α), and interleukin-1ß (IL-1ß) was also found in the tea saponin group. These results suggest that tea saponins have a protective effect against alcohol-induced gastric mucosal damage in mice. Therefore, tea saponin may serve as a food additive for gastric mucosal protection.

Anti-diabetic effect of banana peel dietary fibers on type 2 diabetic mellitus mice induced by streptozotocin and high-sugar and high-fat diet.

We used a high-fat diet (HFD) and streptozotocin (STZ) to induce type 2 diabetic mellitus (T2DM) mice and evaluated the effect of banana peel dietary fibers (BP-DFs) as potential hypoglycemic agents. After 5 weeks of intervention with banana peel dietary fibers (BP-DFs), food intake was reduced, body weight was increased, blood lipids and glucose were reduced, fasting insulin and GLP-1 levels were increased, and liver and pancreatic tissue damage was reduced. Banana peel soluble dietary fiber (BP-SDF) has the most significant effect. The results of fecal microbiota analysis showed that BP-DFs could ameliorates gut microbiome dysbiosis, and all three types of dietary fibers have obvious effects. The results of fecal short-chain fatty acids (SCFAs) showed that the content of fecal SCFAs was increased after BP-DFs dietary intervention, and BP-SDF had the most obvious effect. RT-PCR experiment results show that BP-DFs can up-regulate the mRNA expression levels of PI3K, AKT, IRS-1, and FOXO1 in the liver of diabetic mice, which indicates that BD-DFs may play a role in improving insulin resistance and insulin signal transduction via the IRS/PI3K/AKT pathway, improving insulin resistance and insulin signal transduction. Our research may be extended to BP-DFs, especially BP-SDF, as the basis for potential dietary intervention to prevent or treat type 2 diabetic mellitus. This work supports future research studies of the anti-diabetic properties of BP-SDF in humans. PRACTICAL APPLICATIONS: Diabetes can lead to a variety of complications that have a huge impact on health. Dietary fiber may help in lowering blood sugar. Our experimental results showed that banana peel dietary fibers have the effect of reducing food intake, blood sugar, improving liver and pancreas function, increasing the abundance of intestinal flora, and improving the IRS/PI3K/AKT pathway in T2DM mice. Therefore, this study could provide a theoretical basis for the development of functional foods with banana peel dietary fiber.

Interaction of calf thymus DNA and glucose-based gemini cationic surfactants with different spacer length: A spectroscopy and DLS study.

The interactions between calf thymus DNA and a series of glucose-based cationic gemini surfactants 1a-1c with different spacer length, n = 4, 6 and 8, were studied by UV absorption, fluorescence spectroscopy, circular dichroism, FT-IR, dynamic light scattering and zeta potential measurements. The results showed that all the surfactants could interact with DNA efficiently. On addition of increasing concentration of the surfactants, UV absorption hypochromicity with insignificant blue shift were observed, until the DNA signal disappeared. The surfactant 1c was more efficient in the reduction of absorption intensity of DNA. According to the fluorescence quenching experiments by ethidium bromide exclusion, 1c exhibited the highest binding properties, with the binding constant at 3.25 × 108 L·mol-1. The spectroscopy study indicated that the surfactants bound with the DNA by a non-intercalative mode, mainly electrostatic interaction between the positively charged headgroups of the surfactants and negatively charged phosphate groups of DNA at low concentration, and the hydrophobic interaction among the alkyl chains at high concentration. The conformation of DNA during the interaction process could be kept B-form of DNA. For 1c, the DNA molecules can be compacted to about 103 nm in hydrodynamic diameter at 0.2 mM, while the minimum sizes of DNA were 140 nm and 133 nm, respectively, in the presence of 1a and 1b. The impact of the cationic gemini surfactants on the DNA compaction and condensation would shed light on their potential applications in gene delivery.

Effect of banana pulp dietary fibers on metabolic syndrome and gut microbiota diversity in high-fat diet mice.

Banana (Musa nana Lour.) have the effect of anti-obesity and lipid modulating properties. However, the influences of banana pulp dietary fibers (BP-DF) on metabolic syndrome (MetS) and gut microbiota (GM) are unknown. In this research, we explore a novel strategy for dietary BP-DF on attenuation of lipid metabolic disease, GM disorder, and associated mechanisms in high-fat diet (HFD) mice. BP-DF can strongly suppress on HFD caused body weight and epididymal fat mass gain, and significantly improved serum lipid profiles, liver lipid profiles, and intestinal function. BP-DF also significantly improved fecal short-chain fatty acids formation and fecal ammonia content. BP-DF impacted the intestinal microorganism at all kinds of taxonomic levels by increasing the proportions of beneficial Lactobacillus, Bacteroidales _S24_7_group, and Alloprevotella and decreasing the disease or obesity associated Sutterella, Streptococcaceae, and Erysipelotrichaceae. The experiments show that BP-DF may use as a functional ingredient for preventing obesity, MetS, and intestinal microorganism imbalance. PRACTICAL APPLICATIONS: Obesity result in many metabolic complications, and it poses a great threat to people's health. Nowadays, the introduction of DF may lead to the development of a new strategy in the treatment of obesity and its metabolic syndrome. Our experiments findings show that BP-DF may use as a functional ingredient for preventing obesity, MetS, and intestinal microorganism imbalance. Therefore, BP-DF can be applied to the development and production of functional food, and can also be used as an important food functional ingredient, which can be added to various food, such as bread, noodles, baked goods, cakes, etc., to improve its nutritional value.

Physicochemical properties of polysaccharides separated from Camellia oleifera Abel seed cake and its hypoglycemic activity on streptozotocin-induced diabetic mice.

Two homogeneous polysaccharide fractions named SCP-1 (7.16 × 106 Da) and SCP-2 (2.00 × 104 Da) were purified by DEAE-52 cellulose and Sephadex G-200 column chromatography successively from Camellia oleifera Abel seed cake. They were characterized by Fourier transformed infrared (FT-IR), high performance liquid chromatography (HPLC), nuclear magnetic resonance (NMR) spectroscopy and differential scanning calorimetry (DSC). The monosaccharide compositions of SCP-1 were d­mannose, d­glucose and l­xylose with a molar ratio of 1.77:0.93:1 and that of the SCP-2 were d­mannose, l­rhamnose, d­glucose and l­xylose with a molar ratio of 5.27:1.21:0.16:1. Animal experiments suggested that the plasma glucose levels in hyperglycemia mice were reduced by 11.34%, 30.70%, 46.83% after administration of high, medium and low doses of SCP-1, and reduced by 16.67%, 23.93% and 33.00% after administration of high, medium and low doses of SCP-2, respectively. SCP-1 and SCP-2 also increased the activities of glutathione peroxidase (GSH-Px), catalase (CAT) and superoxide dismutase (SOD), as well as decreased the content of malondialdehyde (MDA) in the hyperglycemia mice. These results suggested that SCP-1 and SCP-2 possessed strong hypoglycemic activities in streptozotocin-induced model mice. In addition, the hypoglycemic activity of SCP-1 was stronger than that of SCP-2.

Purification of Tea Saponins and Evaluation of its Effect on Alcohol Dehydrogenase Activity.

Tea saponins, extracted from a Camellia oleifera cake, were found to have a potent effect on de-alcoholic activity. To obtain highly pure tea saponins, which can better maintain the activity of alcohol dehydrogenase (ADH), this paper presents an extraction method for tea saponins using deionized water as the extraction agent and a two-stage precipitation method, including ethanol precipitation and CaO precipitation. The optimum conditions for ethanol precipitation were 95% alcohol, a duration of 1.5h and a solid/liquid ratio of 1:4; while the optimum conditions for CaO precipitation were a duration of 2h and an NH4HCO3/CaO ratio of 2:1. Under the optimum conditions, the content of saponins was 87.58%. The results showed that the greater the amount of tea saponins and the higher its purity, the more significant its activating effect on ADH. When the purity of tea saponins was above 75%, it activated ADH. It indicated that the de-alcoholic mechanism of tea saponins is associated with the activity of ADH. Furthermore, the study characterized the structure of tea saponins by UV absorption and Fourier Transform Infrared (FTIR) spectrometry and LC-MS.

[Study on the relation between ginkgolide B and water by FTIR].

The method of IR was used to study GB spectrum variety with different water ratio, and it was showed that GB IR spectrum only changed in the absorption strength at 3452, 1793, 1780 and 1630 cm(-1). The reason is that the water was concealed by GB cage skeleton and formed hydroxyl bond with GB hydroxyl groups, and the structure of GB remained unchanged and accorded with standardized GB. With the help of DSC and LC-MS, the subtle relations between GB and water were explained, GB is lipophilic and can not be dissolved by water, but in general, GB is easy to absorb the water of environment, and can be dehydrated under particular conditions.

Determination of the derivative from ginkgolide B.

A new compound decomposed from ginkgolide B(GB) is discovered and identified by MS and UV spectrum. It is the dehydrate of GB, which was named as ginkgolide K before. Differently, it cannot exist independently, but only in equilibrium with GB. It is found first time that 3-hydroxy is active in some solvent.

[Separation and determination of madecassic acid in triterpenic genins of Centella asiatica by high performance liquid chromatography using beta-cyclodextrin as mobile phase additive].

Centella asiatica (L. ) Urban is a tropical medicinal plant with a long history of therapeutic uses. Madecassic acid and terminolic acid, which are a pair of structural isomers, are two constituents of Centella asiatica. A method using reversed-phase high performance liquid chromatography in which beta-cyclodextrin (beta-CD) was the additive in mobile phase has been developed for separation of the structural isomers and determination of madecassic acid. The two compounds can be isolated with high resolution on a C18 reversed-phase column with the addition of beta-CD in the mobile phase. The separation mechanism of the isomers was discussed. It was assumed that the separation of the isomers might have been resulted from different inclusion forces of complexes with beta-CD. The effects of beta-CD concentration and the pH of mobile phase on resolution were investigated. It was found that the resolution of the isomers increased with the increase of beta-CD concentration when the mobile phase consisted of methanol-water (65 : 35, v/v) at pH 4. The correlation coefficient (r2) of the linear calibration curve between peak area and concentration of madecassic acid was 0.998 9 in the range of 0.1 - 5.0 g/L. This method was successfully used to determine the madecassic acid in triterpenic genins of Centella asiatica.

[Isolation and purification of puerarin from puerarin extractive by chelate complex chromatography].

Puerarin, an isoflavone compound, is an important ingredient in traditional Chinese medicine, which has the good medical effects on hypertension and angina. A new type of separation and purification method for isolating puerarin was developed using chelate complex chromatography. The stationary phase was prepared with silica gel containing 7% of Cu(OAc)2 in the chloroform. After the chloroform was evaporated, it was used as chelate complex chromatographic stationary phase to purify puerarin extractive. Pure puerarin was obtained when a mixture of chloroform and methanol (10:1, v/v) was used as eluent. In comparison with a common silica gel column, the chelate complex chromatographic column was more convenient and efficient. The purity and recovery of puerarin, and column capacity were improved 11%, 12% and 200%, respectively. Under the optimized experimental conditions, the purity of puerarin could be as high as with a recovery of 92%.