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Probiotics have poor stability in storage and gastrointestinal digestion, resulting in low biological activity. Therefore, we have innovatively designed a shell-core microbead that can place probiotics in an independent lipid environment as a core, with an outer layer coated with a shell film composed of gelatin and/or pectin. Addition of 3% pectin to the shell layer and cross-linking with calcium ions significantly improved the physicochemical properties of the shell film of the microbeads, including water vapor permeability (WVP), water contact angle (WCA), and gel characteristics. The microbeads have spherical structure, uniform size and low moisture content (<5%). The water solubility of gelatin microbeads (Gel-Mb, 69.62%), gelatin-pectin microbeads (Gel-Pec-Mb, 61.06%) and shell cross-linked microbeads (Cro-Pec-Mb, 52.97%) decreased gradually. Cryo-scanning electron microscopy (Cryo-SEM) showed an evident shell core structure, and an apparent gel network was observed in the surface layer of shell of Cro-Pec-Mb. SEM analysis also showed the same porous network structure on the surface of Cro-Pec-Mb. The probiotic activities of Gel-Mb, Gel-Pec-Mb and Cro-Pec-Mb were 6.87, 6.76 and 6.74 log CFU/g after 4 months storage at 4 °C, respectively. This indicates that microbead encapsulation has a high retention of probiotic activity due to the effective insulation of the lipid environment from oxygen, moisture, etc. Cro-Pec-Mb can maintain the integrity of the structure and resist the enzymatic hydrolysis of digestive enzymes, reducing probiotic inactivation during the gastrointestinal digestion, with only a decrease 1.85 log CFU/g. This study show that microbeads were a promising platform for intestinal probiotic delivery. [Display omitted] • Shell-core microbeads encapsulate probiotics in an independent lipid environment. • Probiotic long-lasting storage stability was increased by shell-core microbeads. • Shell layer cross-linking facilitate the retention of structure during gastrointestinal tract. • Shell layer cross-linking improve probiotic heat resistance and gastrointestinal survival. [ABSTRACT FROM AUTHOR]

Hybrid liposomes, composed of amphiphilic chitosan and phospholipid, were prepared and used to evaluate the effect of amphiphilic polymers on the properties of liposomes. Successful preparation of the hybrid liposomes was confirmed using physicochemical characteristics, including morphology, particle size and zeta potential. Physical stability studies (exposure to solutions of increasing ionic strength and heat treatment) indicated that the hybrid liposomes had better ionic stability than amphiphilic chitosan-based polymeric liposomes and higher thermal stability than traditional phospholipid liposomes. Curcumin was then encapsulated in the hybrid liposomes. Compared with phospholipid liposomes, the hybrid liposomes displayed better storage stability and more sustained curcumin release. Cellular uptake experiments showed that the hybrid liposomes significantly increased the bioavailability of curcumin. The study highlights the potential of well-designed stable hybrid liposomes that increase the stability and bioavailability of lipophilic bioactive, such as curcumin. [ABSTRACT FROM AUTHOR]

Microwave heating is an efficient thermal stimulation approach in developing coalbed methane (CBM). In this paper, a new microwave heating technology for CBM is proposed and two structure schemes of waveguide antennas for heating are designed. After characterizing the mathematical model of the microwave coaxial antenna radiation, the numerical model of coal reservoir heated by microwave is established, which couples both the electromagnetic field and the heat transfer. The electromagnetic field distribution and the temperature changing law in coal reservoir during microwave heating process are solved numerically and verified by the designed experiment. A parametric study on heating effect yields an optimized structure of the microwave antenna, which is SD 6 × R8 and α = 15°. After irradiated by the optimal antenna for 120 min, the average temperature rises to 62 °C (from 20 °C) and the energy efficiency reaches 85%. In different coal reservoirs, the maximum temperature ranges from 169 °C to 1586 °C and the maximum temperature gradient ranges from 2.52 °C/mm to 37.19 °C/mm, which are beneficial to the crack propagation. The microwave heating technology can provide fast and sufficient energy to raise the temperature of coal reservoir and is feasible for enhancing the CBM recovery. [Display omitted] • A microwave heating technology for CBM recovery is designed and simulated. • The mathematical models of antenna radiation and microwave heating are established. • The microwave heating performance under different factors is investigated. • An optimal structure of microwave antenna (SD 6 × R8 and α = 15°) is obtained. [ABSTRACT FROM AUTHOR]