microencapsulation

In the present study, Micro-capsulated fish oil omega-3 fatty acids and Lactobacillus Plantarum produced by electrostatic interaction coacervation was investigated in three biopolymer formulations.

Three biopolymer formulations of fish gelatin-gum Arabic, fish gelatin–chitosan, and gum Arabic-gelatin were used to study the effect of wall materials. Also, we investigated the effect of wall-to-core materials ratio at 2: 1, 3: 1, and 4: 1 and homogenizer speeds of 3500 and 7000 rpm.

The results of the microencapsulation efficiency of omega-3 fatty acids showed that treatment 12 had the highest yield (96.26 ± 0.19). It contained a biopolymer mixture containing gelatin-chitosan which surrounded a high percentage of omega-3, while the amount of omega-3 on the surface of the capsule was very low. Also, treatment 6 containing gelatin wall materials and gum Arabic had a high ability to surround bacteria and compared to free bacteria, the bacterial mortality rate was lower when exposed to simulated gastric conditions. In addition, after being in the simulated intestinal condition, the number of bacteria increased after 120 minutes that shows the capsule has released its compounds in alkaline conditions of the intestine.

This study showed that using the combined coacervation technique using fish gelatin biopolymers, chitosan, and gum Arabic as wall materials, can produce omega-3 capsules and Lactobacillus Plantarum in micrometer sizes. They can play a protective role in preventing the oxidation of probiotic and omega-3 bacteria.

Berberis vulgaris, an Iranian native plant, includes valuable compounds such as berberine with therapeutic, health-promoting and nutritional effects. However, major parts of this plant are discarded as wastes. The major aims of this study were optimization of berberine extraction conditions from the whole plant with maximum antioxidant activity, the extract microencapsulation using complex coacervation and two biopolymer gelatin/flake tragacanth (Astragalus rahensis) and analysis of the physical characteristics of the moist microcapsules.

Berberine extraction was optimized using response surface methodology based on three extraction parameters of time, temperature and solvent:water ratio at three levels and five central points. The berberine concentration was analyzed using high-performance liquid chromatography and its antioxidant activity was studied to investigate the optimized conditions. The optimum extract was microencapsulated using complex coacervation and gelatin/tragacanth with three ratios of 1:1, 2:1 and 1:2 w/w. Furthermore, yield, efficiency, particle size, solubility and the microstructural and release characteristics of the wet microcapsules were characterized.

Optimized extraction conditions with 0.88 desirability included 0.5 h, 22.9 °C and 75% solvent:water ratio. The average surface size of the microcapsules was in the range of 71.31–90.15 μm. Samples with 2:1 ratio indicateds the maximum yield 95.1 and sample with 2:1 ratio showed the maximum solubility of 10%. Efficiency in all samples were similarly 96% ±1.

Complex coacervation using gelatin/tragacanth with a ratio of 1:2 was developed to produce wet microcapsules of the optimum extract of berberine with the highest yield and efficiency and low solubility as well as particle sizes of smaller than 100 μm.

In the recent years, attention to the use of probiotic drugs and probiotic food products, due to probiotic’s functional and health properties has been increased. The storage and the viability of the probiotics in the products and passing through the gastrointestinal tract was always a big challenge. Drying is one of the functional and important choices that can be used for stabilizing microbial species and makes the bacterial usage easy. Among different microencapsulation methods, spray drying is one of the important drying methods that can be used in industrial scale and size. Optimizing the effective parameters on the cultivation and separation of probiotic bacteria, the most important and challenging parameters of spray drying that have influence on probiotic products, and choose of the best wall materials for the cores, are the most important and challenging factors that are necessary for optimizing the microencapsulation in industrial scale. In this review article, the factors affecting the survival and resistance of bacteria in the stage before entering the spray dryer and the factors affecting the survival of probiotic bacteria during the drying stage are discussed. In addition, the important criteria for selecting microfiber wall materials and the tests that are often performed on probiotic microfiber resulting from spray drying have been examined.