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Curcumin has been known and used in the medical and industrial world. One way to improve its stability, bioavailability and its medical applications is using encapsulation method. In this research, we studied cocoliposome (coconut liposome) as the encapsulation material. The encapsulation efficiency (EE), loading capacity (LC), release rate (RR), as well as the free radical scavenging activity, measured by inhibition ratio (IR), of curcumin in encapsulation product were studied on varying cholesterol compositions and in simulated gastric fluid (SGF, pH 1.2) and simulated intestinal fluid (SIF, pH 7.4) conditions. We found that curcumin encapsulation in cocoliposome (CCL) formulation was influenced by cholesterol composition and pH conditions. The EE, LC and free radical scavenging activity diminished under both the SIF and SGF conditions when the cholesterol concentration enhanced. However, the RR increased as the cholesterol intensified. The condition to acquire the most favorable encapsulation parameter values was at 10% cholesterol composition. Furthermore, the IR results at 10% cholesterol concentration of CCL was 67.70 and 82.13% in SGF and SIF milieu, respectively. The CCL formulation thrived better under SIF conditions for free radical scavenging activities.

Cerium oxide (CeO2) was synthesized using the precipitation method at various calcination temperatures ranging from 500 to 700°C. Cerium(III) nitrate hexahydrate (Ce(NO)3.6H2O) was used as the precursor for cerium, while Cetyltrimethylammonium bromide (CTAB) acted as the morphology-directing agent. Characterization results indicated that pure CeO2 was obtained at all calcination temperature variations. Calcination temperature influences crystallinity, crystal size, and CeO2 crystal parameters. The crystallinity and crystal size of CeO2 increased with the rising calcination temperature, reaching values of 81.1-84.5% and 15.58-23.12 nm, respectively, along with larger crystal parameters as the temperature increased (a = 5.406-5.410 Å). Surface morphology showed irregular shapes of CeO2 particles, with decreasing sizes as the calcination temperature increased, ranging from 0.2-5.6 μm at 600°C to 0.12-2.9 μm at 700°C. The Ce/O ratio on the surface increased with the rising calcination temperature, reaching a range of 0.48-0.57. CeO2 obtained from calcination at 600°C exhibited the highest fluorescence emission intensity (λ= 496 nm), indicating the least oxygen vacancies presence. Therefore, for antioxidant and catalyst applications, it is preferable to calcinate CeO2 at 700°C. [ABSTRACT FROM AUTHOR]

Phospholipids are amphiphilic molecules that can be used as basic materials for drug delivery systems. Phospholipids can be obtained from natural sources such as sesame seeds. This study investigated the chemical properties of a phospholipid and the total lipids extracted from sesame seeds. The phospholipid extract, with a yield of 0.475%, was brownish-yellow. It has a crude fat content of 96% comprising of saturated fatty acids (Methyl, 14-methyl-Pentadecanoic acid) and two unsaturated fatty acids (9,12-Octadecadienoic acid and 11-Octadecenoic acid). FTIR analysis of the phospholipid revealed the presence of double bonds and a characteristic choline absorption. The antioxidant screening using the DPPH free radical scavenging method showed 34.16% and 30.98 % antioxidant activity on days 7 and 14, respectively. A peroxide number test revealed that it maintained a low peroxide value of 3.1988 mg O2/g even after 14 days in storage. The study concluded that the phospholipid extract of sesame seed has good antioxidant activity, chemical properties, and quality and could be used as a pharmaceutical excipient in drug delivery. [ABSTRACT FROM AUTHOR]

An experimental and computational study was carried out for encapsulation of vitamin C in sesame, Sesamum indicum L., liposomes. Based on computational studies, the packing parameter (P) of sesame phospholipids was found to be 0.64 ± 0.09. This indicates that the molecular shape of sesame phospholipids is in the form of truncated cone and, in aqueous solution, it self-assembles to form liposomes. In the liposomes, no chemical interaction was observed between phospholipid molecules and vitamin C. However, medium-strength hydrogen bonds (Ei) from -87.6 kJ/mol to -82.02 kJ/mol with bond lengths ranging from 1.746 Å to 1.827 Å were formed between vitamin C and phospholipid molecules. Because of this weak interaction, vitamin C gets released easily from the inner regions of liposome. Empirical experiments were performed to confirm the computation outcomes, where sesame liposomes were found to encapsulate almost 80% of vitamin C in their interior cavities. During the 8 days storage, release of vitamin C occurred gradually from the liposome system, which signifies week interactions in the liposome membranes amongst phospholipid molecules and vitamin C.

A recent study reported that the combination of mangosteen-gotu kola fractions showed lots of bioactivities, such as strong antioxidant, anti-bacterial, and immunomodulatory activities. However, the solubility and bioavailability of the mixture combination of mangosteen-gotu kola fraction were low. Encapsulation of the mixture in a liposome was believed to increase its solubility in water, bioavailability, and medical applications due to the similar structure between a liposome and biological cell membranes. However, liposome system has a weakness, such as low encapsulation ability which are influenced by the manufacture, and the composition of the constituents, namely cholesterol, phospholipids, and encapsulated active substances. Therefore, it was necessary to optimize liposomal formulations that produce liposomes with the best encapsulation capabilities. This study was designed to optimize the encapsulation of mixture combination of mangosteen-gotu kola fraction in liposomes using thin film hydration method and response surface methodology (RSM). The RSM optimization consisted of 13 runs with two experimental factors: mass of the mixture (5.00-15.00 mg) and mass of cholesterol (11.30-22.60 mg) as independent variables. The mass of phospholipid (113.00 mg) was used as a dependent variable. The observed parameters were encapsulation efficiency (EE) and loading capacity (LC). As a result, quadratic models were used for response prediction. The maximum response was obtained using 15 mg of mixture combination, 22.60 mg of cholesterol, and 113 mg of phospholipid. It was shown that EE and LC were 82.42% and 2.18%, respectively. The liposome-loaded mixture combination obtained had a monodispersity form with a particle size and surface charge of 912.7 nm and -24.3 mV, respectively. [ABSTRACT FROM AUTHOR]

Herbs, known for their naturally active chemicals, are currently being reconsidered as a safer alternative medication. The natural substances that are known to have lots of bioactivities, such as antioxidant properties, are mangosteen (Garcinia mangosatana L.) (GM) and kodavan (Centella asiatica L. Urban) (CA). However, the antioxidant activities of the GM-CA combination have not been previously reported. It is essential to investigate the properties of the active fractions to determine which fraction possesses the best antioxidant activities. Therefore, this research aimed to determine the chemical composition and evaluate the antioxidant activities (IC50) and total phenolic content (TPC) of GM, CA, and their combination. The combination is expected to exhibit a synergistic effect and an increase in antioxidant activities. GM and CA were percolated using ethanol and successively partitioned by n-hexane and ethyl acetate. Antioxidant activities and TPC were evaluated using DPPH and Folin Ciocalteu methods, respectively. Chemical components were determined through LC-MS/MS analysis and phytochemical screening. The combination of ethyl acetate fractions (EAF) of GM-CA in a 1:3 ratio indicates synergistic interaction, strong antioxidant activities IC50 = 62.00 ppm, and 132.38 mgGAE/g of TPC. Phytochemical screening showed the presence of flavonoids, terpenoids, and polyphenols. LCMS/MS identified several compounds in GM, such as (+/-) gomisin M2, archangelicin, biodinin A, α-mangosteen, samarcandin acetate, and achilin. In CA, 5,7,2',5'-tetrahydroxy-flavon, 5-hydroxy-6,4'-dimethoxy-flavone-7-O-β-D-glucopyranose, asiaticoside, kaempferol-3,7-diglucoside, madecassoside, 3ß,6ß,23-trihydroxy-urs-12-en-28-oic acid, kaempferol-3-Orutinoside, and mahuannin F, were determined. [ABSTRACT FROM AUTHOR]

This paper provides dynamic insight into the aggregation profile of systems containing six different phospholipid species, cholesterol, and vitamin C thru Coarse-Grain Molecular Dynamics (CGMD) simulations. The simulation used 42 systems, and each system was composed of 220 molecules of each phospholipid species, a varied number of cholesterol molecules (0, 11, 22, 33, 66, 88), and 10 vitamin C molecules. The phospholipid species were DLPE, DOPE, DLiPE, DOPS, DLiPS, and DLiPC. We found curved bilayer, toroidal bilayer, concave micelle, disc-like bilayer, planar bilayer, and liposome structures in the systems during the 40 ns simulation. The systems with a ratio cholesterol:phospholipid between 15% and 40% formed liposomes regardless of the phospholipid species. Cholesterol is positioned in the liposome bilayer while vitamin C is encapsulated in the aqueous core of liposomes for all cholesterol compositions. The cholesterol influences the liposome formation of various phospholipid species and the encapsulation of vitamin C in the liposome structure. [ABSTRACT FROM AUTHOR]