Improvement of the physico-mechanical properties of antibacterial electrospun poly lactic acid nanofibers by incorporation of guar gum and thyme essential oil

Polymeric Nanofibers via Green Electrospinning for Safe Food Engineering

Electrospun functional nanofibers enable controlled release of the loaded active ingredient and an adjustable dissolution rate. However, the widespread use of toxic organic solvents in electrospinning poses risks to human health and the environment whereas increasing production costs and complexity. This article examines the application of eco-friendly electrospinning technologies in food engineering, with a focus on water-based and melt electrospinning methods. It provides a detailed analysis of water-soluble biopolymers and synthetic polymers, highlighting their current applications and challenges in food engineering. Water-based electrospinning is proposed as a sustainable alternative, offering scalability and reduced environmental impact. This transition is essential for advancing food engineering toward more sustainable and environmentally responsible practices.

A comprehensive review of gum-based electrospun nanofibers for food packaging: Preparation, developments, and potential applications

Gums represent an intriguing group of biopolymers utilized in the food industry owing to their exceptional properties. These intricate carbohydrate biomolecules possess the capacity to form gels and mucilage structures by binding with water. Their stabilizing potential, heightened viscosity, emulsifying characteristics, broad compatibility, and cost-effectiveness render them a valuable resource in the realm of food packaging. Electrospun nanofibers (ENFs) derived from gums offer an amplified surface-to-volume ratio in comparison to bulk materials at the macroscopic level, resulting in increased porosity and enhanced mechanical properties. These attributes have the potential to enhance surface functionalities and diversify their range of applications. Despite the limited availability of gum types for the synthesis of ENFs, extensive research has been dedicated to the advancement of gum-based ENFs and the exploration of their applications. This review paper delves into the influence of gum properties on solution spinnability and the prospective applications of gum-based ENFs in active and intelligent food packaging.

Antimicrobial membranes based on polycaprolactone:pectin blends reinforced with zeolite faujasite for cloxacillin-controlled release

Multifunctional membranes applied to biomedical materials become attractive to support the biological agents and increase their properties. In this study, biopolymeric fibers based on polycaprolactone (PCL) and pectin (PEC) were reinforced with faujasite zeolite (FAU) for cloxacillin antibiotic (CLX) loading. FAU with a high specific surface area (347 ± 8 m2 g-1), high crystallinity and particles with a diameter of up to 100 nm were produced under optimized synthesis conditions (100 °C/4 h). Zeolites were incorporated into polymeric nanofibers to be a cloxacillin (CLX) carrier in wound treatment, using electrospinning as an efficient synthesis method. The fibers produced showed good mechanical resistance and the incorporation of CLX was proven by assays to inhibit the growth of Staphylococcus aureus bacteria. The controlled release of CLX in different pH conditions, which simulate the wound environment, was carried out for up to 229 h, achieving a released CLX concentration of up to 6.18 ± 0.02 mg L-1. These results prove that obtaining a hybrid fiber (polymer-zeolite) to incorporate drugs to be released in a controlled manner was successfully achieved. The bactericidal activity of this material shows that its use for measured applications could be an alternative to conventional methods.

Biocomposite Active Whey Protein Films with Thyme Reinforced by Electrospun Polylactic Acid Fiber Mat

Electrospinning is a versatile technique for obtaining nano/micro fibers which are able to significantly change the active properties of composite materials and bring in new dimensions to agri-food applications. Composite bio-based packaging materials obtained from whey proteins, functionalized with thyme essential oil (TEO) and reinforced by electrospun polylactic acid (PLA) fibers, represent a promising solution for developing new active food packaging using environmentally friendly materials. The aim of this study is to obtain and characterize one-side-active composite films covered with a PLA fiber mat: (i) WF/G1, WF/G2, and WF/G3 resulting from electrospinning with one needle at different electrospinning times of 90, 150, and 210 min, respectively, and (ii) WF/G4 obtained with two face-to-face needles after 210 min of electrospinning. While TEO bioactivity is mainly related to its antimicrobial and antioxidant properties, the PLA fiber mat uplifted the composite mechanical and barrier properties of films. The bi-layer films obtained were characterized by SEM, showing the distribution of the electrospun fiber mat and an increased thickness of the PLA layer from WF/G1 to WF/G4, while FTIR spectra showed the structural vibrations of the functional groups. The experimental results show that WF/G4 have a FTIR fingerprint resembling PLA, retained ~50% of the volatile compounds present in the uncovered film (WF/TEO), while it only had 1.41 ± 0.14 (%) of the permeability to octanol of the WF/G1 film. WF/G4 exhibited 33.73% of the WVP of WF/G1 and displayed the highest tensile strength, about 2.70 times higher than WF/TEO. All films studied revealed similar antimicrobial effect against Bacillus cereus, Geotrichum candidum, and Rhodotorula glutinis and good antiradical activity, thus demonstrating good prospects to be applied as food packaging materials. WF/G composite materials are good candidates to be used as bioactive flavoring primary packaging in hard cheese making.

Formulation and application of poly lactic acid, gum, and cellulose-based ternary bioplastic for smart food packaging: A review

In future, global demand for low-cost-sustainable materials possessing good strength is going to increase tremendously, to replace synthetic plastic materials, thus motivating scientists towards green composites. The PLA has been the most promising sustainable bio composites, due to its inherent antibacterial property, biodegradability, eco-friendliness, and good thermal and mechanical characteristics. However, PLA has certain demerits such as poor water and gas barrier properties, and low glass transition temperature, which restricts its use in food packaging applications. To overcome this, PLA is blended with polysaccharides such as gum and cellulose to enhance the water barrier, thermal, crystallization, degradability, and mechanical properties. Moreover, the addition of these polysaccharides not only reduces the production cost but also helps in manufacturing packaging material with superior quality. Hence this review focuses on various fabrication techniques, degradation of the ternary composite, and its application in the food sector. Moreover, this review discusses the enhanced barrier and mechanical properties of the ternary blend packaging material. Incorporation of gum enhanced flexibility, while the reinforcement of cellulose improved the structural integrity of the ternary composite. The unique properties of this ternary composite make it suitable for extending the shelf life of food packaging, specifically for fruits, vegetables, and fried products. Future studies must be conducted to investigate the optimization of formulations for specific food types, explore scalability for industrial applications, and integrate these composites with emerging technologies (3D/4D printing).

Natural gums and their derivatives based hydrogels: in biomedical, environment, agriculture, and food industry

The hydrogels based on natural gums and chemically derivatized natural gums have great interest in pharmaceutical, food, cosmetics, and environmental remediation, due to their: economic viability, sustainability, nontoxicity, biodegradability, and biocompatibility. Since these natural gems are from plants, microorganisms, and seaweeds, they offer a great opportunity to chemically derivatize and modify into novel, innovative biomaterials as scaffolds for tissue engineering and drug delivery. Derivatization improves swelling properties, thereby developing interest in agriculture and separating technologies. This review highlights the work done over the past three and a half decades and the possibility of developing novel materials and technologies in a cost-effective and sustainable manner. This review has compiled various natural gums, their source, chemical composition, and chemically derivatized gums, various methods to synthesize hydrogel, and their applications in biomedical, food and agriculture, textile, cosmetics, water purification, remediation, and separation fields.

Antibacterial aroma compounds as property modifiers for electrospun biopolymer nanofibers of proteins and polysaccharides: A review

Electrospinning is one of the most promising techniques for producing biopolymer nanofibers for various applications. Proteins and polysaccharides, among other biopolymers, are attractive substrates for electrospinning due to their favorable biocompatibility and biodegradability. However, there are still challenges to improve the mechanical properties, water sensitivity and biological activity of biopolymer nanofibers. Therefore, these strategies such as polymer blending, application of cross-linking agents, the addition of nanoparticles and bioactive components, and modification of biopolymer have been developed to enhance the properties of biopolymer nanofibers. Among them, antibacterial aroma compounds (AACs) from essential oils are widely used as bioactive components and property modifiers in various biopolymer nanofibers to enhance the functionality, hydrophobicity, thermal properties, and mechanical properties of nanofibers, which depends on the electrospun strategy of AACs. This review summarizes the recently reported antimicrobial activities and applications of AACs, and compares the effects of four electrospinning strategies for encapsulating AACs on the properties and applications of nanofibers. The authors focus on the correlation of the main characteristics of these biopolymer electrospun nanofibers with the encapsulation strategy of AACs in the nanofibers. Moreover, this review also particularly emphasizes the impact of the characteristics of these nanofibers on their application field of antimicrobial materials.

Development of biomaterials based on chitosan-gelatin nanofibers encapsulated with Ziziphora clinopodioides essential oil and Heracleum persicum extract for extending the shelf-life of vacuum-cooked beef sausages

The aims of the current study were to encapsulate Ziziphora clinopodioides essential oil (ZEO, 0%, 0.15%, and 0.25%) and Heracleum persicum extract (HPE, 0%, 0.25%, and 0.5%) into the chitosan-gelatin (CH-GE) nanofibers through the electrospinning process to improve the shelf-life of vacuum-cooked beef sausages through 70 days of refrigerated storage. Scanning electron microscopy indicated that all nanofibers appeared thin, well-defined, smooth, and possessed uniform thread-like fibers without any beads or nodule formations. The Fourier transform infrared spectroscopy study confirmed the molecular interaction between encapsulated compounds and CH-GE nanofibers. The X-ray diffraction analysis of nanofibers showed an increase in crystallinity after incorporating ZEO and HPE into the polymer. Treated sausages with CH-GE-ZEO 0.25%-HPE 0.25% and CH-GE-ZEO 0.25%-HPE 0.5% showed significantly lower microbial population and lipid oxidation than the control group during the experiment period (P < 0.05). Sausages formulated with designated CH-GE nanofibers had better microbial, chemical, and sensory properties compared to sausages treated with pure ZEO/HPE during refrigerated storage. The findings also showed that treated sausages with CH-GE-ZEO 0.25%-HPE 0.5% had the highest color, odor, texture, and overall acceptability after 70 days of refrigerated storage conditions. Therefore, this treatment could be applicable for the prolonged storage conditions during cooked beef sausage production.

Smart Packaging Based on Polylactic Acid: The Effects of Antibacterial and Antioxidant Agents from Natural Extracts on Physical-Mechanical Properties, Colony Reduction, Perishable Food Shelf Life, and Future Prospective

Changes in consumer lifestyles have raised awareness of a variety of food options and packaging technologies. Active and smart packaging is an innovative technology that serves to enhance the safety and quality of food products like fruit, vegetables, fish, and meat. Smart packaging, as a subset of this technology, entails the integration of additives into packaging materials, thereby facilitating the preservation or extension of product quality and shelf life. This technological approach stimulates a heightened demand for safer food products with a prolonged shelf life. Active packaging predominantly relies on the utilization of natural active substances. Therefore, the combination of active substances has a significant impact on the characteristics of active packaging, particularly on polymeric blends like polylactic acid (PLA) as a matrix. Therefore, this review will summarize how the addition of natural active agents influences the performance of smart packaging through systematic analysis, providing new insights into the types of active agents on physical-mechanical properties, colony reduction, and its application in foods. Through their integration, the market for active and smart packaging systems is expected to have a bright future.

Investigating functional properties of halloysite nanotubes and propolis used in reinforced composite film based on soy protein/basil seed gum for food packaging application

This study aimed to investigate the effect of halloysite nanotubes (HNTs) on the physicochemical characteristics of the soy protein isolated/basil seed gum (SPI/BSG) film activated with propolis (PP). The obtained results of scanning electron microscope (SEM), thermal gravimetric analysis (TGA), and tensile investigations illustrated that the addition of HNTs as nanofiller led to positive changes in the morphology, thermal stability, and mechanical characteristics of SPI/BSG films. The barrier properties of films considerably decreased with incorporation of HNTs. Furthermore, the encapsulation of PP as bioactive agent into the produced films significantly increased (P < 0.05) the antioxidant potential of the samples in DPPH radical-scavenging activity assays. The antibacterial effects of film also significantly increased (P < 0.05) after the encapsulation of PP. In conclusion, the produced films illustrated acceptable efficiency for usage in food packaging system.

Obtaining poly (lactic acid) nanofibers encapsulated with peppermint essential oil as potential packaging via solution-blow-spinning

The development of active packaging based on biodegradable material and incorporating active compounds, such as essential oil, is a new technique to ensure food safety without harming the environment. In this study, nanofiber mats of poly (lactic acid)/ polyethylene glycol (PLA/PEG) blend incorporated with peppermint essential oil (PO) at different ratios (5-20 % v/w) were produced by solution-blow-spinning (SBS) for potential packaging application. Electron microscopy showed a cylindrical and interlaced morphology for PLA/PEG/PO and a significant increase in the diameter (139-192 nm) of the nanofibers by increasing PO content. All nanofibers showed high thermal stability (278-345 °C) suitable for use in the food industry. Nuclear magnetic resonance (¹³C NMR) spectrum confirmed PO in the nanofibers after SBS. ATR-FTIR spectral analysis supported the chemical composition of the nanofiber mats. PO addition led to obtaining hydrophobic nanofibers, enhancing the contact angle to 122° and decreasing water vapor permeability (60 % reduction compared to the PLA/PEG (3.0 g.mm.kPa^-1.h^-1.m^-2). Although the PLA/PEG/20%PO nanofibers did not show halo formation in 24 h, they effectively extended the strawberries' shelf-life at 25 °C, evidencing PO release over time. It also reduced weight loss (2.5 % and 0.3 % weight loss after 5 days for PLA/PEG and PLA/PEG/20%PO, respectively) and increased firmness (8-12 N) for strawberries packed with the nanofiber mats. It is suggested that PLA/PEG films incorporating PO may be used as an active, environmentally friendly packaging material.

Release Profiles of Carvacrol or Chlorhexidine of PLA/Graphene Nanoplatelets Membranes Prepared Using Electrospinning and Solution Blow Spinning: A Comparative Study

Nanofibrous membranes are often the core components used to produce devices for a controlled release and are frequently prepared by electrospinning (ES). However, ES requires high production times and costs and is not easy to scale. Recently, solution blow spinning (SBS) has been proposed as an alternative technique for the production of nanofibrous membranes. In this study, a comparison between these two techniques is proposed. Poly (lactic acid)-based nanofibrous membranes were produced by electrospinning (ES) and solution blow spinning (SBS) in order to evaluate the different effect of liquid (carvacrol, CRV) or solid (chlorhexidine, CHX) molecules addition on the morphology, structural properties, and release behavior. The outcomes revealed that both ES and SBS nanofibrous mat allowed for obtaining a controlled release up to 500 h. In detail, the lower wettability of the SBS system allowed for slowing down the CRV release kinetics, compared to the one obtained for ES membranes. On the contrary, with SBS, a faster CHX release can be obtained due to its more hydrophilic behavior. Further, the addition of graphene nanoplatelets (GNP) led to a decrease in wettability and allowed for a slowing down of the release kinetics in the whole of the systems.

Properties of galactomannans and their textile-related applications-A concise review

Galactomannans are reserve carbohydrates in legume plants and are primarily extracted from their seeds. They contain galactose side chains throughout the mannose backbone and have unique features such as emulsifying, thickening, and gelling together with biodegradability, biocompatibility, and non-toxicity, which make them an appealing material. Guar gum and locust bean gum mainly are used in all galactomannan needed applications. Nonetheless, tara gum and fenugreek gum have also attracted considerable attention in recent decades. Despite the increased usage of galactomannans in the textile-related fields in recent years, there is no review article published yet. To fill this gap and to demonstrate the striking and increasing importance of galactomannans, a concise summary of the properties of common galactomannans and their comparisons is given first, followed by an account of recent developments and applications of galactomannans in the textile-related fields. The associated potential opportunities are also provided at the end of this review.

Influence of Herbal Fillers Addition on Selected Properties of Silicone Subjected to Accelerated Aging

This work aims to assess the impact of the type and percentage of powdered herbs on selected properties of silicone-based composites. The matrix was an addition cross-linked platinum-cured polydimethylsiloxane. The fillers were powdered thyme and sage, which were introduced at 5, 10, and 15 wt.%. The introduced fillers differed in composition, morphology, and grain size. The grain morphology showed differences in the size and shape of the introduced fillers. The qualitative and quantitative assessment resulting from the incorporation was conducted based on tests of selected properties: density, wettability, rebound resilience, hardness, and tensile strength. The incorporation slightly affected the density and wettability of the silicone. Rebound resilience and hardness results differed depending on the filler type and fraction. However, tensile strength decreased, which may be due to the matrix's distribution of fillers and their chemical composition. Antibacterial activity evaluation against S. aureus proved the bacteriostatic properties of the composites. Accelerated aging in PBS solution further deteriorated the mechanical properties. FTIR and DSC have demonstrated the progressive aging of the materials. In addition, the results showed an overall minimal effect of fillers on the silicone chemical backbone and melting temperature. The developed materials can be used in applications that do not require high mechanical properties.

New perspectives on electrospun nanofiber applications in smart and active food packaging materials

Packaging plays a critical role in determining the quality, safety, and shelf-life of many food products. There have been several innovations in the development of more effective food packaging materials recently. Polymer nanofibers are finding increasing attention as additives in packaging materials because of their ability to control their pore size, surface energy, barrier properties, antimicrobial activity, and mechanical strength. Electrospinning is a widely used processing method for fabricating nanofibers from food grade polymers. This review describes recent advances in the development of electrospun nanofibers for application in active and smart packaging materials. Moreover, it highlights the impact of these nanofibers on the physicochemical properties of packaging materials, as well as the application of nanofiber-loaded packaging materials to foods, such as dairy, meat, fruit, and vegetable products.

Guar Gum/Ethyl Cellulose-Polyvinyl Pyrrolidone Composite-Based Quartz Crystal Microbalance Humidity Sensor for Human Respiration Monitoring

In this work, the guar gum (GG) and the electrospinned ethyl cellulose-polyvinyl pyrrolidone (EC-PVP) nanofibers were used as humidity-sensitive materials for fabricating a quartz crystal microbalance (QCM) sensor. Fourier transform infrared spectroscopy, scanning electron microscopy, water contact angle test, and X-ray photoelectron spectra were used to characterize the synthesized GG/EC-PVP composite material, confirming its successful preparation and good hydrophilicity. The humidity sensitivity experiments were performed at room temperature. The GG/EC-PVP-coated QCM sensor has high sensitivity (55.72 Hz/%RH) and low hysteresis (2.8% RH) in a wide relative humidity range (0-97% RH), short response/recovery time (26/2 s), excellent selectivity, good repeatability, and stability. The combined action of hydrophilic groups and porous structure enhances the humidity sensitivity. The GG/EC-PVP sensor can be used to capture and measure typical breathing patterns in different human basic emotions due to its good performance. Furthermore, a lie-detector system was also designed for judging the lying through detecting the emotional breathing pattern of the subjects.

Electrospinning of PLA Nanofibers: Recent Advances and Its Potential Application for Food Packaging

Poly(lactic acid), also abbreviated as PLA, is a promising biopolymer for food packaging owing to its environmental-friendly characteristic and desirable physical properties. Electrospinning technology makes the production of PLA-based nanomaterials available with expected structures and enhanced barrier, mechanical, and thermal properties; especially, the facile process produces a high encapsulation efficiency and controlled release of bioactive agents for the purpose of extending the shelf life and promoting the quality of foodstuffs. In this study, different types of electrospinning techniques used for the preparation of PLA-based nanofibers are summarized, and the enhanced properties of which are also described. Moreover, its application in active and intelligent packaging materials by introducing different components into nanofibers is highlighted. In all, the review establishes the promising prospects of PLA-based nanocomposites for food packaging application.

Fabrication of Biohybrid Nanofibers by the Green Electrospinning Technique and Their Antibacterial Activity

The development of bioactive polymer nanofiber sheets based on eco-friendly components is required to meet the needs of various medical applications as well as to preserve the environment. This study aimed to fabricate biohybrid nanofibers based on water-soluble polymers and aqueous extract of myrrh. The myrrh extract was incorporated into poly(vinyl alcohol)/tragacanth gum nanofiber mats (myrrh@PVA/TG) by the green electrospinning technique. Various characteristics of the prepared fibers such as morphology, fiber diameter distribution, crystallinity, and thermal stability were studied. The results confirmed that the morphology of biohybrid nanofibers was uniform without beads and tragacanth gum plays an important role in controlling the average diameter of fibers and the crystallinity. The antibacterial properties of the developed biohybrid nanofibers were investigated against common pathogens of Gram-positive and Gram-negative bacteria by the standard disc diffusion method. A significant antibacterial activity was observed toward bacterial strains after incorporation of aqueous myrrh extract into nanofibers, which increased on increasing the extract ratio. Due to their eco-friendly components and significant antibacterial activity, the prepared biohybrid nanofibers will open new avenues toward incorporating aqueous herbal extracts into degradable polymer fibers for use in many antibacterial applications.

Multifunctional colorimetric cellulose acetate membrane incorporated with Perilla frutescens (L.) Britt. anthocyanins and chamomile essential oil

A colorimetric cellulose acetate (CA) membrane incorporated with Perilla frutescens (L.) Britt. anthocyanins (PFA) and chamomile essential oil (CO) is developed via electrospinning technique for food freshness monitoring and shelf-life extending. The moieties of PFA and CO are well-dispersed in fiber matrix by hydrogen bonds and their incorporation increases the fiber size but with no obvious influence on the fiber morphology at incorporation levels. The presence of CO enhances membrane hydrophobicity. The target membrane of CA-PFA6-CO15 (PFA6%, CO15%) has a wide color change range of pH 2-12 which is high sensitive and reversible towards external pH-stimuli. The membrane has good antibacterial activity against E. coli and S. aureus besides antioxidant activity. The release of bioactive moieties is predominantly controlled by Fickian diffusion. The target membrane can simultaneously monitor pork freshness in real-time and double the shelf-life at 25 °C, indicating its potential application in active and intelligent food packaging.

Sustainable Applications of Nanofibers in Agriculture and Water Treatment: A Review

Natural fibers are an important source for producing polymers, which are highly applicable in their nanoform and could be used in very broad fields such as filtration for water/wastewater treatment, biomedicine, food packaging, harvesting, and storage of energy due to their high specific surface area. These natural nanofibers could be mainly produced through plants, animals, and minerals, as well as produced from agricultural wastes. For strengthening these natural fibers, they may reinforce with some substances such as nanomaterials. Natural or biofiber-reinforced bio-composites and nano–bio-composites are considered better than conventional composites. The sustainable application of nanofibers in agricultural sectors is a promising approach and may involve plant protection and its growth through encapsulating many bio-active molecules or agrochemicals (i.e., pesticides, phytohormones, and fertilizers) for smart delivery at the targeted sites. The food industry and processing also are very important applicable fields of nanofibers, particularly food packaging, which may include using nanofibers for active–intelligent food packaging, and food freshness indicators. The removal of pollutants from soil, water, and air is an urgent field for nanofibers due to their high efficiency. Many new approaches or applicable agro-fields for nanofibers are expected in the future, such as using nanofibers as the indicators for CO and NH3. The role of nanofibers in the global fighting against COVID-19 may represent a crucial solution, particularly in producing face masks.

Investigation of Mechanical, Chemical, and Antibacterial Properties of Electrospun Cellulose-Based Scaffolds Containing Orange Essential Oil and Silver Nanoparticles

This study demonstrated a controllable release properties and synergistic antibacterial actions between orange essential oil (OEO) and silver nanoparticles (AgNPs) incorporated onto cellulose (CL) nanofibers. The preparation of AgNPs attached on CL nanofibers was conducted through multiple processes including the deacetylation process to transform cellulose acetate (CA) nanofibers to CL nanofibers, the in situ synthesis of AgNPs, and the coating of as-prepared silver composite CL nanofibers using OEO solutions with two different concentrations. The success of immobilization of AgNPs onto the surface of CL nanofibers and the incorporation of OEO into the polymer matrix was confirmed by SEM-EDS, TEM, XRD, and FT-IR characterizations. The tensile strength, elongation at break, and Young’s modulus of the nanofibers after each step of treatment were recorded and compared to pristine CA nanofibers. The high antibacterial activities of AgNPs and OEO were assessed against Gram-positive B. subtilis and Gram-negative E. coli microorganisms. The combined effects of two antimicrobials, AgNPs and OEO, were distinctively recognized against E. coli.

Engineering of Liposome Structure to Enhance Physicochemical Properties of Spirulina plantensis Protein Hydrolysate: Stability during Spray-Drying

Encapsulating hydrolysates in liposomes can be an effective way to improve their stability and bioactivity. In this study, Spirulina hydrolysate was successfully encapsulated into nanoliposomes composed of different stabilizers (cholesterol or γ-oryzanol), and the synthesized liposomes were finally coated with chitosan biopolymer. The synthesized formulations were fully characterized and their antioxidant activity evaluated using different methods. Then, stabilization of coated nanoliposomes (chitosomes) by spray-drying within the maltodextrin matrix was investigated. A small mean diameter and homogeneous size distribution with high encapsulation efficiency were found in all the formulations, while liposomes stabilized with γ-oryzanol and coated with chitosan showed the highest physical stability over time and preserved approximately 90% of their initial antioxidant capacity. Spray-dried powder could preserve all characteristics of peptide-loaded chitosomes. Thus, spray-dried hydrolysate-containing chitosomes could be considered as a functional food ingredient for the human diet.

Stabilization Techniques of Essential Oils by Incorporation into Biodegradable Polymeric Materials for Food Packaging

Human health, food spoilage, and plastic waste, which are three great topical concerns, intersect in the field of food packaging. This has created a trend to replace synthetic food preservatives with natural ones, to produce bio-functional food packaging, and to shift towards biodegradable polymeric materials. Among the natural bioactive agents, essential oils are gaining more and more attention in food packaging applications due to their various benefits and fewer side-effects. However, their volatility, hydrophobicity, and strong odor and taste limit the direct use in food-related applications. Fixation into polymeric matrices represents a suitable strategy to promote the benefits and reduce the drawbacks. Emulsification and electrospinning are largely used techniques for protection and stabilization of essential oils. These methods offer various advantages in active food packaging, such as controlled release, ensuring long-term performance, decreased amounts of active agents that gain enhanced functionality through increased available surface area in contact with food, and versatility in packaging design. This review focuses on creating correlations between the use of essential oils as natural additives, stabilization methods, and biodegradable polymeric matrices or substrates in developing bioactive food packaging materials. Documentation was performed via the Scopus, ScienceDirect, and PubMed databases, selecting the publications after the year 2018. Particular attention was given to the publications that tested materials on food/food pathogens to evaluate their performances in retarding spoilage. Research gaps were also identified on the topic, materials being tested mainly at short time after preparation without considering the long-term storage that usually occurs in actual practice between production and use, and insufficient research related to upscaling.

Mini Review: Advances in 2-Haloacid Dehalogenases

The 2-haloacid dehalogenases (EC 3.8.1.X) are industrially important enzymes that catalyze the cleavage of carbon-halogen bonds in 2-haloalkanoic acids, releasing halogen ions and producing corresponding 2-hydroxyl acids. These enzymes are of particular interest in environmental remediation and environmentally friendly synthesis of optically pure chiral compounds due to their ability to degrade a wide range of halogenated compounds with astonishing efficiency for enantiomer resolution. The 2-haloacid dehalogenases have been extensively studied with regard to their biochemical characterization, protein crystal structures, and catalytic mechanisms. This paper comprehensively reviews the source of isolation, classification, protein structures, reaction mechanisms, biochemical properties, and application of 2-haloacid dehalogenases; current trends and avenues for further development have also been included.

An In Vitro Study of Antibacterial Properties of Electrospun Hypericum perforatum Oil-Loaded Poly(lactic Acid) Nonwovens for Potential Biomedical Applications

The growth of population and increase in diseases that cause an enormous demand for biomedical material consumption is a pointer to the pressing need to develop new sustainable biomaterials. Electrospun materials derived from green polymers have gained popularity in recent years for biomedical applications such as tissue engineering, wound dressings, and drug delivery. Among the various bioengineering materials used in the synthesis of a biodegradable polymer, poly(lactic acid) (PLA) has received the most attention from researchers. Hypericum perforatum oil (HPO) has antimicrobial activity against a variety of bacteria. This study aimed to investigate the development of an antibacterial sustainable material based on PLA by incorporating HPO via a simple, low-cost electrospinning method. Chemical, morphological, thermal, thickness and, air permeability properties, and in vitro antibacterial activity of the electrospun nonwoven fabric were investigated. Scanning electron microscopy (SEM) was used to examine the morphology of the electrospun nonwoven fabric, which had bead-free morphology ultrafine fibers. Antibacterial tests revealed that the Hypericum perforatum oil-loaded poly(lactic acid) nonwoven fabrics obtained had high antibacterial efficiency against Escherichia coli and Staphylococcus aureus, indicating a strong potential for use in biomedical applications.