Antimicromial and antioxidant bioactive films based on poly(lactic acid)/poly(trimenthylene carbonate) films incorporated with different concentrations of oregano essential oil (OEO) were prepared by solvent casting. The antimicrobial, antioxidant, physical, thermal, microstructural, and mechanical properties of the resulting films were examined. Scanning electron microscopy analysis revealed that the cross-section of films became rougher when OEO was incorporated into PLA/PTMC blends. Differential scanning calorimetry analysis indicated that crystallinity of PLA phase decreased by the addition of OEO, but this did not affect the thermal stability of the films. Water vapor permeability of films slightly increased with increasing concentration of OEO. However, active PLA/PTMC/OEO composite films showed adequate barrier properties for food packaging application. The antimicrobial and antioxidant capacities were significantly improved with the incorporation of OEO (p < 0.05). The results demonstrated that an optimal balance between the mechanical, barrier, thermal, antioxidant, and antimicrobial properties of the films was achieved by the incorporation of 9 wt % OEO into PLA/PTMC blends.

A novel medical adhesive was prepared by blending poly(lactic acid) (PLA) with poly(trimethylene carbonate) (PTMC) in ethyl acetate, and the two materials were proven to be biodegradable and biocompatible. The medical adhesive was characterized by ¹H nuclear magnetic resonance (¹HNMR), gel permeation chromatography (GPC), scanning electron microscopy (SEM) and differential scanning calorimetry (DSC). The water vapor transmission rate (WVTR) of this material was measured to be 7.13 g·cm⁻²·24 h⁻¹. Its degree of comfortability was confirmed by the extensibility (E) and the permanent set (PS), which were approximately 7.83 N·cm⁻² and 18.83%, respectively. In vivo tests regarding rabbit immunoglobulin M (IgM), rabbit immunoglobulin G (IgG), rabbit bone alkaline phosphatase (BALP), rabbit interleukin 6 (IL-6), rabbit interleukin 10 (IL-10), rabbit tumor necrosis factor α(TNFα), glutamic-oxaloacetic transaminase (AST/GOT), glutamic-pyruvic transaminase (ALT/GPT), alkaline phosphatase (AKP), blood urea nitrogen (BUN) and creatinine (Cr) indicated that the PLA-PTMC medical adhesive was not harmful to the liver and kidneys. Finally, pathological sections indicated that PLA-PTMC was more effective than the control group. These data suggest that in addition to having a positive effect on hemostasis and no sensibility to wounds, PLA-PTMC can efficiently prevent infections and has great potential as a medical adhesive.

BF-30 is a single chain polypeptide of an N-segment with an α-helix from cathelicidin gene encoding, and it contains 30 amino acid residues, with a relative molecular mass and isoelectric point of 3637.54 and 11.79, respectively. Cathelicidin-BF-30 was entrapped in four-arm star-shaped poly(ethylene glycol-b-dl-lactic acid-co-glycolic acid) block copolymers (4-arm-PEG-PLGA) by a double-emulsion solvent-evaporation method. Three release phases of cathelicidin-BF-30loaded 4-arm-PEG-PLGA microspheres were observed, including an initial burst-release phase, followed by a lag phase with minimal drug release and finally a secondary zero-order release phase. The delivery system released BF-30 over more than 15 days in vitro. Furthermore, the material for preparing the microspheres has good biocompatibility and biodegradability. Additionally, based on the drug resistance of food pathogenic bacteria, the antibacterial effects of BF-30 on Shigella dysenteriae CMCC 51105 (Sh. dysenteriae CMCC 51105), Salmonella typhi (S. typhi) and Staphylococcus aureus (S. aureus) as well as the stability of the in vitro release of the BF-30-loded microspheres were studied. The α-helix secondary structure and antibacterial activity of released BF-30 were retained and compared with native peptide. These BF-30 loaded microspheres presented <10% hemolysis and no toxicity for HEK293T cells even at the highest tested concentration (150 μg/mL), indicating that they are hemocompatible and a promising delivery and protection system for BF-30 peptide.

An efficient and catalyst-free synthesis of trisubstituted allylic sulfones through an allylic sulfonylation reaction of Morita-Baylis-Hillman (MBH) carbonates with sodium sulfinates has been developed. Under the optimized reaction conditions, a series of trisubstituted allylic sulfones were rapidly prepared in good to excellent yields (71%–99%) with good to high selectivity (Z/E from 79:21 to >99:1). Compared with known synthetic methods, the current protocol features mild reaction temperature, high efficiency and easily available reagents.

Polylactic acid (PLA) is limited in its application due to its high price, high brittleness and low glass-transition temperature. Modification methods are currently used to overcome these shortcomings. In this study, Bletilla striata polysaccharide (BSP) was blended with PLA by a solvent method. DMA data showed that the BSP/PLA film had a higher glass-transition temperature, and the glass-transition temperature of the film showed an extreme value of 68 °C when the proportion of the chalk polysaccharide was 0.8%. TG data indicates that the composite film material has good thermal stability. Tensile tests show that the composite film is improved in rigidity and elasticity compared to the pure PLA film. The blending modification of PLA with white peony polysaccharide not only reduces the cost of PLA, but also improves the thermal and mechanical properties of PLA.

In order to enrich the types of Panax notoginseng saponins (PNS) sustained-release preparations and provide a new research idea for the research and development of traditional Chinese medicine sustained-release formulations, a series of Panax notoginseng saponins microspheres was prepared by a double emulsion method using a series of degradable amphiphilic macromolecule materials polyethylene glycol monomethyl ether-polymandelic acid (mPEG-PMA) as carrier. The structure and molecular weight of the series of mPEG-PMA were determined by nuclear magnetic resonance spectroscopy (¹ HNMR) and gel chromatography (GPC). The results of the appearance, particle size, drug loading and encapsulation efficiency of the drug-loaded microspheres show that the mPEG10000-PMA (1:9) material is more suitable as a carrier for loading the total saponins of Panax notoginseng. The particle size was 2.51 ± 0.21 μm, the drug loading and encapsulation efficiency were 8.54 ± 0.16% and 47.25 ± 1.64%, respectively. The drug-loaded microspheres were used for in vitro release and degradation experiments to investigate the degradation and sustained release behaviour of the drug-loaded microspheres. The biocompatibility of the microspheres was studied by haemolytic, anticoagulant and cytotoxicity experiments. The pharmacological activity of the microspheres was studied by anti-inflammatory and anti-tumour experiments. The results showed that the drug-loaded microspheres could be released stably for about 12 days and degraded within 60 days. At the same time, the microspheres had good biocompatibility, anti-inflammatory and anti-tumour activities.