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The objective of this study was to prepare a biodegradable poly (DL-lactide) injectable gel of tinidazole. The formulation parameters evaluated in this study included polymer molecular weight, polymer concentration, solvent and drug loading, and orthogonal design was used to optimize the formulation. The preferable formulation was that 30% (w/w) poly(DL-lactide) (MW is 5 700) dissolved in 70% (w/w) N-methyl-2-pyrrolidone with 4%-6% (w/w) tinidazole.

The objective of the study was to evaluate the effect of a novel biodegradable membrane on the prevention of postoperative adhesion formation. The membrane was prepared by blending 50% PLA (polylactic acid) with 50% PTMC (polytrimethylene carbonate). The prepared blends polymer membrane was more flexible than pure PLA membrane, as measured by glass-transition temperature and tensile study. Cytotoxicity study revealed that PLA/PTMC blends membrane showed good biocompatibility. The membrane elicited slight tissue reaction based on the results of histological study. Thirty adult Japanese rabbits were used for the intestine adhesion model. The treatment group had PLA/PTMC membrane, the control group had chitosan, and the blank control group was not operated. The animals were housed for two weeks and sacrificed to investigate adhesion of intestine. Compared with the blank control group, the treatment group and the control group lowered the extent of adhesions (p < 0.01), but the treatment group was better than the control group (p < 0.05). The in-vivo studies confirmed that PLA/PTMC blends membrane could prevent postoperative adhesions., ((c) 2006 Wiley Periodicals, Inc.)

Nisin was loaded in mesoporous silica nanoparticles (MSN) (0, 1, 2 and 3 wt%) and incorporated into poly (lactic acid) (PLA) matrix by casting method. The mechanical property, water vapor permeability, thermal property, and antimicrobial property of PLA nanocomposite films were measured. And the internal structure of the composite film was observed through the Scanning electron microscope. Meanwhile, the kinetic of nisin releasing from food simulated solution was investigated and the migration model was established. The result showed that mesoporous silica had an effect on the mechanical and thermal property of the composite films. Both water vapor transmission rate (WVP) and oxygen permeation rate (OTR) decreased, especially for 3MSN/NI/PLA, where WVP decreased by about 9.64% and OTR decreased by 35.19%, which was beneficial to improve the preservation effect. With the addition of MSN, the amount of loaded nisin increased, and at 3MSN/NI, the nisin loading reached 88.75%, and the mesoporous silica could effectively control the release of nisin, thus prolonging the preservation effect. The release kinetic of nisin was described by Fick's law and Weibull's model. In short, the PLA nanocomposite film has the potential to be used as an antimicrobial active film by adding nisin as an antimicrobial agent. Highlights: A biodegradable antimicrobial food grade film was prepared.Nisin was added to the films as an antimicrobial agent.The ordered mesoporous structure of MSN was used as a carrier of antimicrobial agent.The film effectively inhibits E. coli and S. aureus by controlling the release of nisin.Fick's law and Weibull's model were used to describe the release kinetics of Nisin. [ABSTRACT FROM AUTHOR]

BACKGROUND: Our living environment is being increasingly polluted by petroleum‐based plastics and there is an increasing demand for biodegradable food packaging. In this study, the effect of various ultrahigh‐pressure (UHP) treatments (0, 200 and 400 MPa) on the microstructure and thermal, barrier and mechanical properties of poly(lactic acid) (PLA)/ZnO nanocomposite films was studied. RESULTS: The film‐forming solution was processed using UHP technology. The crystallinity, strength and stiffness of the composite film after UHP treatment increased. In addition, barrier property analysis showed that the UHP treatment significantly (P < 0.05) reduced the oxygen permeability and water vapor permeability (WVP) coefficient of the PLA/ZnO nanocomposite film. Furthermore, the WVP value of the film treated at 400 MPa (50 g kg−1 nano‐ZnO content) was the lowest and reduced by 47.3% compared with that of pure PLA film. The improvement in these properties might be due to the interaction between nano‐ZnO and PLA matrix promoted by UHP treatment. CONCLUSIONS: Therefore, the application of UHP technology on the film‐forming solution could improve the crystallinity and functional properties of the nanocomposite film, and has great potential in the production of food packaging films with ideal functions. © 2021 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Poly(lactic acid) (PLA) is the most suitable for biodegradable packaging film because of its excellent integrated property, but the poor gas barrier property is its weakness. In this study, a nanocomposite film based on PLA incorporated with 0‐, 1‐, 3‐, 5‐, 10‐, or 15‐wt% nano‐Ag was developed. Effect of multiscale structure on the barrier properties of PLA/nano‐Ag films was studied. The PLA nanocomposite film with 5‐wt% nano‐Ag had the lowest water vapor permeability (WVP) value. Oxygen transmission rate (OTR) value for PLA nanocomposites with 3‐wt% nano‐Ag was found to be the lowest among all the samples. Multiscale structure was demonstrated by the scanning electron microscopy, Fourier transform‐infrared spectroscopy, X‐ray diffraction measurement, and differential scanning calorimetry results. The crystallinity of the PLA phase increased with the content of nano‐Ag in the PLA composites. The evolution of the PLA phase crystallinity could improve the barrier properties of PLA/nano‐Ag composite films for food packaging applications. From the view of multiscale structure, it is better to achieve a balance among short‐range conformation in the amorphous region, long‐range‐ordered structure, and ordered aggregated structure to improve the barrier properties of PLA/nano‐Ag composite films. [ABSTRACT FROM AUTHOR]

The effect of poly(lactic acid) (PLA)/poly(ε-caprolactone) (PCL)/thymol(TH) composite film, PLA/PCL film, and polyethylene (PE) film on the microbial and physicochemical quality of hot pepper ( Capsicum frutescens L.) stored at 4 ± 1 °C for 28 days was studied. The measured properties of hot peppers included weight loss, color, firmness, headspace atmosphere in package, vitamin C, total phenolic content, microbial, and sensory quality. The results indicated that the PLA/PCL/TH packaging can retard the harmful change of microbial, weight loss, anaerobic respiration, firmness, vitamin C, total phenolic content, and sensory quality. The color of hot peppers did not show significant ( p < 0.05) changes during the whole storage time. The results suggested that the PLA/PCL/TH composite film could maintain the quality of fresh hot peppers and extend its postharvest life. [ABSTRACT FROM AUTHOR]

This study aimed to reinforce the barrier performance (i.e., oxygen–gas and water–vapor permeability) of poly(lactic acid) (PLA)-based films. Acetyltributylcitrate and zinc oxide nanoparticle (nano-ZnO), serving as plasticizer and nanofiller, respectively, were blended into a PLA matrix through a solvent-volatilizing method. The structural, morphological, thermal, and mechanical performances were then studied. Scanning electron microscopic images showed a significant dispersion of nano-ZnO in PLA ternary systems with low nano-ZnO content. The interaction between PLA matrix and ZnO nanoparticles was further analyzed by Fourier-transform infrared spectroscopy. Wide-angle X-ray scattering spectroscopy demonstrated high compatibility between PLA matrix and ZnO nanoparticles. Mechanical property studies revealed good tensile strength and low flexibility. Differential scanning calorimetry curves proved that an amorphous structure mostly existed in PLA ternary systems. The improvements in barrier property and tensile strength indicated that the PLA/nano-ZnO composite films could be used for food packaging application. [ABSTRACT FROM AUTHOR]

The use of biodegradable packaging films for post-harvest preservation of wild edible mushrooms is an eco-friendly method. In this study, the nanocomposite films were prepared based on poly (lactic acid) and mesoporous silica (2, 4 and 6 wt% based on polylactide) loaded with citral. The effects of nanocomposite film on the postharvest quality and specific spoilage bacteria of Russula virescens wild mushroom were evaluated. The results showed that firmness, weight loss, color, electrolyte leakage for Russula virescens treated with mesoporous silica loaded with citral based on poly (lactic acid) films were maintained compared to the control group. In particular, the 4% mesoporous silica loaded with citral group prolonged the freshness of mushroom by 6 days. Acinetobacter , Lactococcus, Weissella, Serratia, unclassified Enterobacteriaceae , and unclassified Gammaproteobacteria were identified as the main dominant bacteria. After 12 d of storage, the relative abundance of these bacterial for mushrooms packed by 4 wt% mesoporous silica loaded with citral based on poly (lactic acid) film was reduced, except Lactococcus. This revealed that the poly (lactic acid) film prepared by 4 wt% mesoporous silica loaded with citral could be used to extend the shelf life of Russula virescens. • The MSN/CIT/PLA film inhibited POD and PPO enzyme activities. • The MSN/CIT/PLA film retarded the browning of R. virescens wild mushroom. • The relative abundance of bacteria for MSN/CIT/PLA group was reduced. • The MSN/CIT/PLA film could extend the shelf life of R. virescens. • 4MSN/CIT/PLA film was the most effective in preserving freshness of R. virescens. [ABSTRACT FROM AUTHOR]

The poly(lactic acid) (PLA)/nano-TiO 2 composite films with different nano-TiO 2 loading (0 wt%, 1 wt%, 5 wt%, 10 wt%, 15 wt%, and 20 wt%) were prepared and contacted with 50% (v/v) ethanol solution as food simulant to study the behavior of nano-TiO 2 migration. The structural changes and intermolecular interactions were determined by scanning electron microscopy (SEM), X-ray diffraction (XRD), and differential scanning calorimetry (DSC). The migration amount increased with the increase of initial nano-TiO 2 content. SEM images demonstrated that the microstructure of PLA nanocomposite films became rougher as exposure to ethanol solution in a few days. XRD spectra indicated that a decrease in the intensity of specific diffraction peak occurred as the decrease in nano-TiO 2 content of PLA nanocomposite films during exposure to ethanol simulant. DSC analysis confirmed that the higher crystallinity percentage obtained during the different degradation times. The reasonable food packaging application of the nano-TiO 2 composite films with restrained nano-TiO 2 migration could be accomplished by controlling the nano-TiO 2 loading. • PLA/nano-TiO 2 films were contacted with 50% (v/v) ethanol solution as food simulant. • The migration amount increased with the increase of initial nano-TiO 2 content. • PLA nanocomposite films became rougher as exposure to ethanol solution in a few days. • A decrease in the peak intensity occurred during exposure to ethanol simulant. • Restrained nano-TiO 2 migration could be accomplished by controlling nano-TiO 2 loading. [ABSTRACT FROM AUTHOR]