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Shellac wax (SHW) is a natural, organic resin obtained from insects such as Laccifer lacca. Poloxamer (P) is synthesized tri-block copolymer consists of hydrophilic and hydrophobic blocks arranged in a tri-block structure. In this experiment, the matrix tablets comprising various ratios of P and SHW were fabricated with fusion method. Hydrophilic and hydrophobic model drugs in this study were propranolol hydrochloride (PRN) and hydrochlorothiazide (HCTZ), respectively. Water sorption and erosion behaviors and drug release patterns were investigated. Tablet weight and hardness was slightly increased as the content of P increased due to higher density of P than that of SHW. The swollen tablet was obtained when using higher amount of P. In contrast, tablet erosion was observed in matrix tablets comprising lower content of P. The swelling of matrix tablets comprising 7:3 and 8:2 of P: SHW ratios could promote the prolongation of the drug release; thus, they show the potential for using as the matrix base for controlled drug delivery systems.

The aim of this study was to develop bio-based adhesives that can be used for various packaging papers. In addition to commercial paper samples, papers produced from harmful plant species in Europe, such as Japanese Knotweed and Canadian Goldenrod, were used. In this research, methods were developed to produce bio-based adhesive solutions in combinations of tannic acid, chitosan, and shellac. The results showed that the viscosity and adhesive strength of the adhesives were best in solutions with added tannic acid and shellac. The tensile strength with adhesives of tannic acid and chitosan was 30% better than with commercial adhesives and 23% for combinations of shellac and chitosan. For paper from Japanese Knotweed and Canadian Goldenrod, the most durable adhesive was pure shellac. Because the surface morphology of the invasive plant papers was more open and had numerous pores compared to the commercial papers, the adhesives penetrated the paper structure and filled the voids. There was less adhesive on the surface and the commercial papers achieved better adhesive properties. As expected, the bio-based adhesives also showed an increase in peel strength and exhibited favorable thermal stability. In summary, these physical properties support the use of bio-based adhesives use in different packaging applications.

11 pags., 7 figs., 2 tabs. -- This article belongs to the Special Issue Cleaning Strategies for Cultural Heritage, The removal of aged varnish on artistic paintings is a delicate intervention and the use of UV laser for this purpose is of special relevance. In particular, the use of nanosecond-pulsed lasers operating at 213 nm has been noted to produce good results in mock-up samples, but it has not been tested in real artworks. In this paper, we report on the application of this procedure for the first time on a contemporary oil easel painting with naturally aged varnish. The obtained results were compared with those achieved using traditional solvents, specifically a mixture of ligroin:acetone. Additionally, hot water was used to remove surface dirt. The performance of the different cleaning procedures was assessed with a range of techniques, including low-power microscopy, UV lamp illumination, laser-induced fluorescence (LIF), and laser-induced breakdown spectroscopy (LIBS). Of the tested treatments, the best performance is obtained by nanosecond laser irradiation at 213 nm using an adequate laser fluence (typically 0.14 J/cm2) that allows controlled and efficient removal of the outermost aged varnish layer without affecting the underlying non-aged varnish and paint layers., This research was funded by the Spanish State Research Agency (AEI) through the project SCOCHLAS (Study and Conservation of Cultural Heritage with Lasers, PID2019-104124RB-I00/AEI/1013039/501100011033), by the Community of Madrid through the project Top Heritage-CM (Tecnologías en Ciencias del Patrimonio, S2018/NMT_4372), and by the H2020 project IPERION HS (Integrated Platform for the European Research Infrastructure ON Heritage Science, GA 871034). L. Maestro-Guijarro’s participation was financed by a Youth Guarantee contract (CAM20_IQFR_AI_06) from the Community of Madrid.

A new tablet system was examined for an intestinal delivery system using hydroxypropyl methylcellulose (HPMC) and shellac. HPMC was incorporated into the inside of the tablet, and shellac was coated on the surface, which was evaluated for its controlled-release property through several dissolution tests, firstly in vitro and then via two kinds of clinical studies with healthy volunteers. The clinical studies were originally designed by employing X-ray photography for the movements of the tablets in the gastrointestinal tract and an electronical device to easily analyze the absorption profile of glucose, a model compound. It was found that the dissolution of the tablet was strongly suppressed in a simulated gastric fluid (pH 1.2) and subsequently started to disintegrate in a simulated intestinal fluid (pH 6.8). The first human study with X-ray photography revealed that the model tablets could pass through the stomach without disintegrating. The controlled release of the tablets was further confirmed via analyses of the AUC, Cmax, and Tmax for the blood glucose concentration with other volunteers. The AUC and Cmax were significantly reduced by using our system, thus concluding that the delivery system combined with the addition of HPMC and a shellac coating unequivocally leads to controlled release in the human gastrointestinal tract.

The purpose of the present investigation was to formulate and evaluate anti-nail-biting lacquers consisting of bitter herbal extracts. The hydroalcoholic extracts obtained from Andrographis paniculata and Tinospora crispa were determined for phytochemical constituents, total phenolic contents, antioxidant activities, anti-inflammatory activities, and cytotoxicities. Anti-nail-biting lacquers were prepared by using herbal extracts (bittering agent), shellac (film forming polymer), ethanol (volatile solvent), and other indispensable additives with continuous stirring. Thus, attempts to enhance the film property and bitterness are accomplished by using polyvinylpyrrolidone (PVP K30) as a copolymer and varying concentrations of herbal extracts. Good accepted formulations were established for drying time, pH, viscosity, smoothness of film, film strength, water resistant, and solubility in simulated saliva and evaluated their bitterness in human volunteers. The results revealed that phytochemical constituents including tannins, glycosides, reducing sugars, alkaloids, terpenoids, and flavonoids were found present in both extracts while saponins were only detected in A. paniculata extract. Although T. crispa extract exhibited a significantly higher (p<0.05) total phenolic content and antioxidant activity than A. paniculata extract, it showed lower protein denaturation inhibition property than A. paniculata extract. Because of the potentials of both extracts without cytotoxicity, anti-nail-biting lacquers containing either A. paniculata extract or T. crispa extract were developed and evaluated. Drying time of formulations was 6-11 min with visually seen glossiness of formulation. Formulations of the nail lacquer showed good pH, viscosity, smoothness of film, film strength, water resistant, and solubility in simulated saliva. The formulations displaying no significant cytotoxicity effect on CRL-2076 cells were assessed on healthy human volunteers to compare bitterness and film characteristics. The results revealed that the optimized formulation containing A. paniculata extract could successfully achieve good film forming property and bitterness release which is considered promising for stopping nail biting.

A thin layer of hydroxyapatite (HAp) coating has been developed on Ti6Al4V substrates using a dip-coating process. An intermediate layer of shellac (natural resin) was applied in between the substrate and the coating film to improve the adhesion strength without the need for any secondary annealing process. The adhesion strength was measured as 7.14 MPa. The surface of the developed coating was characterized using a scanning electron microscope. The total coating thickness was found to be 30 microns, and the surface roughness parameters were measured as 0.93 μm (Ra), 1.17 μm (Rq), and 6.67 μm (Rz). The dip-coated samples were also subjected to dissolution behavior study and in vitro study. The measured parameters of the coating suggest the use of this method as an alternative to other expensive and temperature-dependent coating methods for producing HAp coating with better adhesion strength.

Natural food additives are widely applied to processed foods, but their maximum usage levels and acceptable daily intake have not been established in most cases. Moreover, relatively little information is available about the safety aspects of natural food additives compared with synthetic ones. We evaluated the cytotoxicity of five natural food additives frequently used in South Korea, such as smoke flavors, erythritol, inositol, shellac, and γ-oryzanol, at practical usage levels to provide basic information about their potential toxicity and for further in vivo studies. The cytotoxicity was assessed for cell viability, membrane damage, and reactive oxygen species generation in cultured intestinal cells and intestinal barrier models. The highest concentrations for cytotoxicity evaluation were set based on their maximum usage and daily intake levels from the Item Manufacturing Report and the Korea Health and Nutrition Examination Survey, respectively. The results showed that the natural additives tested did not exhibit cytotoxicity at their maximum usage and daily intake levels; however, the cytotoxicity of smoke flavors could be affected by manufacturing forms. Additionally, the potential antioxidant activity of erythritol, inositol, and γ-oryzanol was found. The natural food additives tested did not exhibit cytotoxicity at their maximum usage levels. However, the cytotoxicity of smoke flavors was affected by manufacturing forms, suggesting the importance of manufacturing process for the safety of natural food additives.

With the strict demands by modern society of low-carbon, biodegradability, and eco-friendliness, developments of novel preservative films are required to replace the traditional ones. In this study, all-natural casein and shellac were co-assembled into homogeneous networks (CSFs), which was performed by simply dissolving both biopolymers at pH 12 followed by neutralization of the alkalinity. The replacement of calcium bridges in casein by shellac created more dexterity of the CSFs due to greater molecular flexibility of shellac than calcium, whereby contributing to promoted material elongation and toughness. To further enhance the moisture holding capacity, the CSFs were plasticized by glycerol, yielding smoother films (Gly-CSFs) with tensile strength and toughness being up to 3.55 MPa and 2.05 MJ/m3, respectively. The Gly-CSFs were then functionalized by eugenol (Eug-Gly-CSFs) to enable antioxidant and antibacterial properties. Based on rice cakes as the experimental models, the Eug-Gly-CSFs significantly retarded the mildew growth and extended the shelf-life of the rice cakes. This study utilized synergistic interplay between casein and shellac as a facile tool to assemble preservative films with biodegradability, bacteriostasis, and favorable mechanical properties.

Shelf life in ground and tree nuts are often assessed based on aesthetic appearance, nut integrity, color and most importantly, taste and edibleness. Nuts with considerable level of rancidity and free fatty acids due to degradation of oils indicate expiration or decay. We prepared a shellac-lemongrass oil blend coating using food-grade ingredients and assessed its potential to extend shelf life of Pili nut (Canarium ovatum) kernels. A glossy, hard but considerably brittle coating for the pili kernels were prepared with varying numbers of layers. On average, the mass of coating added per dip is 0.10 g, and the thickness of 5-layers of coating is 0.3 mm. The obtained reflectance spectra of the coated pili kernels implied the translucent nature of the coating, but becomes opaque as the number of layers are increased. Peroxide value (PV) and free fatty acid value (FFAV), were also measured at 10 days after application of coating. PV was lowest in the nuts with 5 coating layers, while this treatment did not reduce FFAV. These results indicate the effectiveness of our coatings in preventing peroxide production probably by blocking oxygen penetration and ultraviolet exposure, which are important triggers production of peroxide and other free radicals. Further tests and time-series experiments are planned to assess the dynamics of peroxide levels and the overall potential of our coating technology for Pili nut.

In this paper, crude flakes (CFs) of shellac were converted into purified, nonwoven, thermospun fibers (shellac floss) using two devices, namely, an electric thermospinner (ETS) and a microwave thermospinner (MTS). This conversion was achieved by the action of heating and the centrifugal forces that arose toward the outside of the spinner-head cavity. The dissolved MTS floss was bleached using hydrogen peroxide to produce the bleached MTS floss. The unbleached shellac (CFs, ETS floss, and MTS floss) and the bleached MTS floss were characterized physically and chemically. There was no deterioration in the floss properties due to the heating tools or bleaching process. For the unbleached shellac, although there were no statistical differences in properties among the three shellac types (CFs, ETS floss, and MTS floss), except for insolubility in hot alcohol, acid value, and moisture content, the MTS floss exhibited superior values compared with the other types for nearly all the properties studied. Bleaching the MTS floss produced the greatest color change among other studies, caused a high reduction in insoluble solid matter due to increasing the solubility of some of the solid constituents of shellac, and slightly decreased its Young’s modulus (E). The important dental applications were surveyed and it was suggested that the suitability was enhanced by using the bleached MTS floss, based on its superior whiteness, along with the unique properties detected.

Shellac (SL) is a natural resin employed for wood finishing, while clove (Eugenia caryophyllata) and thyme (Satureja hortensis) essential oils (C-EO, T-EO) are organic natural products of vegetal origin with antifungal, antimicrobial and antioxidant properties. The present paper aims at exploring the potential of modifying alcoholic shellac solutions with essential oils (C-EO, T-EO), focussing on the recurrent effects of this modification on the traditional wood finishing technique, the colour and the UV light resistance of the wood coated surfaces. The compatibility of C-EO and T-EO with ethyl alcohol and the alcoholic reference SL solution was evaluated, and modified SL solutions with a content of 5% and 10% C-EO and T-EO were prepared. Wood samples of European maple (Acer pseudoplatanus) and European walnut (Juglans regia) were finished with reference and modified SL solutions. An accelerated UV ageing test was run, and the samples were evaluated after 24, 48 and 72 h of exposure. Colour measurements in the CIELab system and FTIR–ATR investigation were employed for monitoring colour and surface chemistry changes. Coating with SL resulted in visible colour changes for both wood species (ΔE values of 31.06 for maple and 13.00 for walnut) and increased UV resistance, reducing colour changes after 72 h UV exposure (by 83% for maple and by 59% for walnut) as compared to the uncoated controls. Modification of SL solutions with C-EO and T-EO only slightly influenced the colour of finished surfaces (ΔE = 1.88–5.41 for maple, ΔE = 1.36–3.41 for walnut) and their UV resistance. The colour changes (ΔE) of coated surfaces after 72 h exposure varied in the range 1.63–4.53 for maple and 2.39–3.58 for walnut, being generally slightly higher (by 1.7–2.9 units for maple and 0–1 unit for walnut) for the modified SL solutions. FTIR investigation highlighted only minor chemical changes of the shellac coating films after 72 h of UV exposure. A photo-induced oxidative process of eugenol seemed possible in the case of SL modified with C-EO.

Amir Maghrabia,1 Mariza Boughdady,2 Mahasen Meshali2 1Department of Pharmacy, Urology and Nephrology Center, Mansoura University, Mansoura, 35516, Egypt; 2Department of Pharmaceutics, Faculty of Pharmacy, Mansoura University, Mansoura, 35516, EgyptCorrespondence: Amir MaghrabiaDepartment of Pharmacy, Urology and Nephrology Center, Mansoura University, Mansoura, 35516, EgyptTel +201007285809Fax +20502247496Email amir2007_pharm@yahoo.comPurpose: Development of new strategies for oral delivery of existing antibiotics administered exclusively through intravenous route is one of the global priorities of pharmaceutical research. The encapsulation of these active pharmaceutical agents within nanosized natural products offers several traits due to their tunable surface properties. Ceftriaxone (CTX) is an injectable, third-generation cephalosporin that suffers poor oral bioavailability.Methods: In the present study, ionic gelation of two biopolymers, namely chitosan (CH) and shellac (SH), was implemented to consolidate CTX, within elegant nanoparticles (NPs) for oral administration that would increase its bioavailability and sustainability. Quality by design approach (23 full factorial design) was adopted to optimize CTX-loaded nanoparticles. The optimized formula (F2) was characterized through transmission electron microscopy (TEM), Fourier transform infrared (FT-IR) spectroscopy and differential scanning calorimetry (DSC). In vitro release behavior and stability study were also evaluated. Pharmacokinetic studies of enteric-coated hard gelatin capsules (HGCs) loaded with F2-NPs were finally assessed.Results: The optimized spherical F2-NPs had a mean particle size of 258 nm, zeta potential of about +30.1 and appreciable drug entrapment efficiency of 83%. The in vitro drug release profile of F2-NPs in pH 7.4 experienced biphasic configuration with an initial burst release for an hour, followed by a sustained release over 15 h with Higuchi model and non-Fickian diffusion mechanism (R2=0.9852). High stability upon storage at refrigerated and room temperature for 3 months and good flow properties (θ= 32.2 and HR= 1.13) of the optimized formula were also conferred. In vivo pharmacokinetic assessment in rabbits fruitfully displayed 92% absolute bioavailability of CTX.Conclusion: The obtained results provide evidence for the potential combination of CH and SH in NPs preparation to enhance the oral bioavailability of CTX.Keywords: ceftriaxone, chitosan, shellac, nanoparticles, oral, factorial design

Aim of this work is to apply protective and homogeneous shellac coating layers on the surface of hydrophilic open-pore cellulose aerogel particles with low densities ≤ 0.1 g/cm3 and high specific surface areas in the range of ~ 400–450 m2/g while keeping the aerogels’ microstructure intact during processing. For this purpose, an innovative miniaturized spouted bed setup was used. Successful process settings for application of enclosed films on aerogel surfaces without intrusion of coating material into the pores were determined. Precise control of coating layer thickness in the range of 10–50 µm was achieved due to variation of coating solution amount without agglomeration and clogging events occurring during processing. Comparison of bulk densities and specific surface areas before and after coating proved the intactness of the porous structure. Coating of particles loaded with vanillin led to controlled release, enhancing release half-life times from 20 to 1600 min. Overall, a successful strategy for coating of organic low-density aerogels was developed.

Polymer nanoparticles (NPs) have attracted significant interest in the past years for drug delivery and triggered release. However, it remains a significant challenge to produce polymer NPs with controlled properties and tunable drug loading. Traditional nanoprecipitation often leads to low drug loading. This study reports the development of a new microfluidic nanoprecipitation approach for making polymer NPs with tunable drug loading up to 50%. The synthesized curcumin-loaded shellac NPs remain very stable for the period of our experiments (10 days) under acidic conditions (pH 4.5), but release the payload at neutral pH in a sustained manner. This work provides a new strategy for making drug-loaded polymer NPs with tunable drug loading and triggered release.

Fast-growing Chinese fir wood has shortfalls such as loose structure and low strength because it grows faster than natural trees. Resin impregnation is a great way to increase the strength of fast-growing fir. However, the resin used for impregnation is a kind of urea-formaldehyde resin, phenolic formaldehyde resin, melamine formaldehyde resin, and the like, which introduce harmful substances such as formaldehyde or phenolic into the wood. In this paper, Chinese fir wood was impregnated with natural shellac polymer, and the effects of impregnation variables on the mechanical properties of the wood were examined. The increase in strength in compression perpendicular to grain (SCPG) of wood samples impregnated with 15% shellac solution achieved a maximum value of 39.01%, but the modulus of rupture (MOR) was slightly reduced. The effects of the impregnation pressure, time, and their interaction were investigated by the response surface method (RSM). ANOVA analysis revealed that the impregnation pressure and time and the interaction between the two seemed to have a significant effect on ∆SCPG. Based on the response face model, the corresponding optimal parameters obtained are 1.0 MPa and 16.0 min for impregnation pressure and time, respectively. By impregnating fir wood with the above optimal conditions, the SCPG increased by 85.78%, whereas the MOR decreased by the least amount.

Three kinds of melamine-formaldehyde (MF) microcapsules, containing transparent shellac, purple shellac, and yellow shellac as core curing agents, were synthesized via in situ polymerization, and then were embedded into the water-based acrylic resin coatings according to the concentrations of 0, 3.0%, 6.0%, 9.0%, 12.0%, and 15.0%, respectively, to obtain waterborne films with different microcapsule contents. The color of different shellacs was relevant to the color parameters of the self-healing waterborne film. The content of microcapsules was negatively correlated with the chromatic aberration of the surface of waterborne films. When the content of microcapsules was 0–6.0%, the chromatic aberration of waterborne films was relatively low. The content of microcapsules and the color of the different shellacs would affect the light transmittance of waterborne films. Among all samples, the light transmittance of the waterborne film containing 3.0% transparent shellac microcapsules was the highest. The microcapsules with different colors of shellac in waterborne films had different self-repairing effects. When the content of microcapsules did not exceed 6.0%, the tensile repair rate of the waterborne film containing yellow shellac encapsulated microcapsules was the highest, at 47.19%. The scratch experiment illustrated that the scratch width of the waterborne coating with yellow shellac microcapsules decreased most significantly, and the width change rate was 73.0% after 5 days. The coating containing the 3.0% yellow shellac microcapsule has the best comprehensive performance on optical and self-healing properties. Exploring the influence of shellac resin’s color and the microcapsules’ content on the waterborne film provides technical references for the application of shellac in waterborne coatings and contribute to the further development of the preparation process of self-healing coatings.

A molded pulp is increasingly used as eco-packaging, but it has poor water resistance. Therefore, surface coating is common to perform on pulp or paper packaging to overcome this shortcoming. In this study, the bagasse (BG) molded pulp sheets were mono-and bilayer coated with nanofibrillated cellulose (NFC), modified NFC (mNFC), and shellac (S) by using a spin coating technique. Surface morphology, surface wettability, water absorption, and mechanical properties of the coated sheet samples were evaluated and compared to the uncoated sample. It was found that mNFC could effectively provide an even and complete coverage coating layer on the BG-based sheet (BG/mNFC), thanks to the partially substituted ester groups. On the contrary, NFC could not be coated evenly on the BG-based sheet surface (BG/NFC) due to its tendency towards agglomeration. The homogeneity of surface obtained from the first layer coating by NFC or mNFC affected the surface quality of the second layer coating by shellac. As a result, the BG/mNFC/S bilayer coated sample showed the smoothest surface and also the highest water resistance confirmed by SEM, contact angle measurement, and water absorption results. Furthermore, the tensile properties of both bilayer coated samples (BG/NFC/S and BG/mNFC/S) were significantly improved (p.05) as compared to the uncoated BG sample. This results suggested that the current bilayer coating system is very promising for advancing the performance of molded pulps in novel packaging uses.

This is an attempt to develop thermally stable shellac–epoxy coating blends with flame-retardant properties. The monophosphazene and silicon precursors were synthesized with PCl5 and dichlorodimethylsilane (DCMS) as phosphorus and silicon sources, respectively. The synthesized phosphazene and silicon precursor moieties were then reacted with shellac in various concentrations to prepare the modified shellac. The shellac/modified shellac and epoxy coatings were then mixed to form the blend formulations and coated onto the mild steel panels. The structure confirmation of both the precursors was achieved using physicochemical analysis, FTIR and NMR, while the modified shellac was characterized using FTIR. Furthermore, the thermal, mechanical and flame-retardant properties of the coating blends were analyzed. The Tg values and the degradation curves showed that the coating blends with Si and P modification were more thermally stable than the unmodified shellac blends. The maximum LOI obtained was 27 for the highest concentrations of P and Si in the coating, similarly, the calculations based on the char yields of LOI also showed the similar trend of increasing values although the values were lower than the practical LOI values. The barrier properties were predicted depending on the results of water absorption and gel content values which showed that the crosslinking density was increasedwith increasing concentrations of shellac in the coating.

The development of functional edible films is promising for the food industry, and improving the water barrier of edible films has been a research challenge in recent years. In this study, curcumin (Cur) was added to zein (Z) and shellac (S) to prepare an edible composite film with a strong water barrier and antioxidant properties. The addition of curcumin significantly reduced the water vapor permeability (WVP), water solubility (WS), and elongation at break (EB), and it clearly improved the tensile strength (TS), water contact angle (WCA), and optical properties of the composite film. The ZS–Cur films were characterized by SEM, FT-IR, XRD, DSC, and TGA; the results indicated that hydrogen bonds were formed among the curcumin, zein, and shellac, which changed the microstructure and improved the thermal stability of the film. A test of curcumin release behavior showed controlled release of curcumin from the film matrix. ZS–Cur films displayed remarkable pH responsiveness, strong antioxidant properties, and inhibitory effects on E. coli. Therefore, the insoluble active food packaging prepared in this study provides a new strategy for the development of functional edible films and also provides a possibility for the application of edible films to extend the shelf life of fresh food.

Background The promising applications of polymers have recently attracted increasing interest in the food industry, prompting the development and utilization of novel polymers with critical roles in future foods. One such polymer with significant advantages in food applications is ‘shellac,’ a long-established natural polymer furnished with distinctive properties, including pH-responsiveness, biodegradability, and biocompatibility. Scope and approach In this review, literature involving food-related shellac applications, selected from Web of Science, were used in content development. First, various shellac sources, extraction methods, and processing methods are introduced, and their chemical compositions and identification reviewed. Subsequently, the physicochemical properties of shellac are discussed in detail. Finally, the applications of shellac in the food industry are comprehensively reviewed. Key findings and conclusions The extraction and processing technology for shellac have matured, and the structure of shellac is now clearly understood. Based on the recognized structures and properties of shellac, its application is widely advantageous in all aspects of the food industry. However, the development of new food-related shellac applications is dependent on fabrication information based on existing research reports, hence the need for elucidation. In addition, the constraints of shellac, which results from self-polymerization, and their consequent effects on the stability of shellac-based food systems are rarely reported, and it is necessary to address these issues. In general, the application of shellac in the food industry shows great potential.

Polymeric material plays an important role as a matrix former in the modulation of drug release of antimicrobial-loaded in situ forming gel (ISG) for efficient periodontitis treatment. This study was conducted to compare three polymers, namely bleached shellac (BS), Ethocel (EC) and Eudragit RS (ERS), as matrix formers of doxycycline hyclate (DH)-loaded solvent exchange-induced ISG. All prepared ISGs, except 25% EC ISG, exhibited the Newtonian flow behaviour. Transformation from solution into matrix-like was achieved rapidly within 5 min. Increasing the amount of these polymers extended the release of DH. DH-loaded EC and ERS ISG systems exhibited high antimicrobial activity, and all ISGs were effective in inhibiting the growth of Staphylococcus aureus, Escherichia coli, Streptococcus mutans, Porphyromonas gingivalis and Candida albicans. By comparison, the DH-loaded ERS ISG, through the solvent exchange mechanism, was found to be ease in injection with low viscosity and sustained the release with higher concentration, meanwhile, it also exhibited interesting in vitro degradability and antimicrobial activities. Therefore, the DH-loaded ERS ISG exhibited a potential use for localized periodontal drug delivery system for the treatment periodontitis.

Drug-coated balloons have proved to be an effective technology in percutaneous transluminal angioplasty in treating peripheral artery disease. Paclitaxel-based coating is mainly used. Solutions to such problems as drug loss and inefficient drug release during operations, however, have not been found yet. This study aims to explore the activity of a newly designed paclitaxel-coated balloon in vitro using pectin as the excipient (pectin-paclitaxel) compared with the commercially available shellac excipient balloon, and to characterize the novel nanoparticle paclitaxel-coated balloon with peptide (Arg-Gly-Asp-Ser, RGDS) derivative RGDS-OC8H17 (pectin-RGDS-OC8H17-paclitaxel). Two coating solutions, pectin-paclitaxel and pectin-RGDS-OC8H17-paclitaxel, were successively designed and prepared. The morphology of both coating solutions was first characterized compared with the control group, the commercially available paclitaxel-coated balloon. Then the in vitro experiments were conducted to determine the drug-releasing profiles of both pectin-paclitaxel and pectin-RGDS-OC8H17-paclitaxel coatings. The pectin-RGDS-OC8H17-paclitaxel-coated balloon was smoother and more homogeneous compared with the commercially available paclitaxel-coated balloon and the pectin-paclitaxel-coated balloon. This difference was more obvious when paclitaxel was at low concentration. During the in vitro trial, the drug-releasing curve of the pectin-RGDS-OC8H17-paclitaxel model showed an adjustable paclitaxel-releasing: more than 90% of the paclitaxel released in 2 h at 300 rpm and more than 99% released in 10 min at 1200 rpm. Compared to the performance of the current commercially available shellac excipient products and the pectin-paclitaxel coating, pectin-RGDS-OC8H17-paclitaxel coating provided higher drug-releasing speed. However, the clinical outcomes of this finding need to be further demonstrated. Paclitaxel-coated balloons as an effective therapeutic strategy currently in treating peripheral arterial disease need to be further improved in terms of its efficiency in anti-proliferative drug delivery and release. The pectin-RGDS-OC8H17-paclitaxel coating solution developed in this study exhibited excellent drug-releasing properties. Further experiments are still needed to demonstrate the performance of this novel drug-coated balloon in vivo and its clinical importance.

Microalgae and cyanobacteria are effective platforms for environmental remediation (phycoremediation), particularly of air and water. There is limited scope to deploy suspension cultures due to space, cost and maintenance challenges—driving an imperative towards biofilm-based treatment systems; however, these systems are ill-equipped for rapid and mobile deployment. In this study we explored the main technical challenges to developing cheap, accessible and low-maintenance engineered biofilm systems (biocomposites) comprising cyanobacteria (Synechococcus elongatus) immobilised to a range of textiles (n = 4) by natural or synthetic latex binders (n = 16), chitosan or shellac. Biocomposite viability (measured as net CO2 uptake) was assessed over 20 days in semi-batch trials. No maintenance was required during this period as the humidity within the reactor was sufficient to support metabolism. Two commercial natural latex binders (AURO 320 and 321) supported strong growth within the biocomposite, outperforming suspension controls. There was variation in textiles performance, with an 80/20 polyester-cotton blend performing most consistently. Biocomposite formulation was varied in terms of binder solids content and cell loading rate, with 5% solids and 2.5% cell loading the most effective combination. We demonstrate the technical feasibility of fabricating functional textile-based cyanobacteria biocomposites and discuss this within the context of developing decentralised wastewater treatment services.

Candida urinary tract biofilms are increasingly witnessed in nosocomial infections due to reduced immunity of patients and the hospital ecosystem. The indwelling devices utilized to support patients with urethral diseases that connect the unsterilized external environment with the internal environment of the patient are another significant source of urinary tract biofilm infections. Recently, nanoparticle (NP)-associated therapeutics have gained traction in a number of areas, including fighting antibiotic-resistant bacterial biofilm infection. However, most studies on nanotherapeutic delivery have only been carried out in laboratory settings rather than in clinical trials due to the lack of precise in vitro and in vivo models for testing their efficiency. Here we develop a novel biofilm-infected 3D human urothelial cell culture model to test the efficiency of nanoparticle (NP)-based antifungal therapeutics. The NPs were designed based on shellac cores, loaded with fluconazole and coated with the cationic enzyme lysozyme. Our formulation of 0.2 wt% lysozyme-coated 0.02 wt% fluconazole-loaded 0.2 wt% shellac NPs, sterically stabilised by 0.25 wt% poloxamer 407, showed an enhanced efficiency in removing Candida albicans biofilms formed on 3D layer of urothelial cell clusteroids. The NP formulation exhibited low toxicity to urothelial cells. This study provides a reliable in vitro model for Candida urinary tract biofilm infections, which could potentially replace animal models in the testing of such antifungal nanotechnologies. The reproducibility and availability of a well-defined biofilm-infected 3D urothelial cell culture model give valuable insights into the formation and clearing of fungal biofilms and could accelerate the clinical use of antifungal nanotherapeutics.

The present study focuses on extracting chitosan from crustacean shells. The as-prepared chitosan was used to develop a uniform thin layer coating on titanium alloy (Ti6Al4V) implant material. Shellac, a natural resin was used intermediately for providing better adhesion. Taguchi optimization technique was used to optimize the control parameter values. Dipping duration and concentration of shellac were considered as control parameters and adhesion strength & thickness of the coating were considered as response characteristics. The concentration of shellac significantly affected the adhesion strength, whereas the thickness increased with an increase in dipping duration. Cytotoxicity tests and corrosion studies were performed on the samples coated with optimal values. The chitosan-coated sample was found as non-toxic and also showed better corrosion resistance.

Made available in DSpace on 2021-06-25T11:48:04Z (GMT). No. of bitstreams: 0 Previous issue date: 2021-01-01 Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Empresa Brasileira de Pesquisa Agropecuaria (EMBRAPA) from Brazil Coatings are generally applied to fruit as microemulsions, but nanoemulsions are still experimental. 'Nova' mandarins (Citrus reticulata) were coated with shellac or carnauba (Copernica cerifera) microemulsions or an experimental carnauba nanoemulsion; these were compared with an uncoated control during storage for 7 days at 20 degrees C. Coatings were also tested on 'Unique' tangors (C. reticulata x C. sinensis) stored for 14 days at 10 degrees C followed by a simulated marketing period of 7 days at 20 degrees C. Fruit quality evaluations included weight loss, gloss, soluble solids (SS), titratable acidity (TA), pH, SS/TA ratio, internal CO2, O-2, fruit juice ethanol, and other aroma volatile content. Sensory visual shine and tangerine (C. reticulata) flavor rank tests after storage were conducted, followed by an off-flavor rating. The carnauba waxes resulted in less weight loss compared with the uncoated control and shellac coating during both experiments. There were no differences in gloss measurements of 'Nova' mandarins; however, shellac-coated fruit ranked highest for shine in a sensory test. For 'Unique' tangors, initially, shellac showed the highest gloss (shine) measurement; however, at the end of storage, the nanoemulsion exhibited the highest gloss, although it was not different from that of the microemulsion. Similarly, after storage, the nanoemulsion ranked highest for visual shine, although it was not different from that of the microemulsion. There were only minor differences in SS, TA, pH, and SS/TA among treatments. The internal CO2 gas concentration and juice ethanol content generally increased and internal O-2 decreased during storage. The highest levels of CO2 and ethanol were found for the shellac treatment, as was the lowest O-2, indicating anaerobic respiration. There were only minor differences among the other coating treatments; however, they were only sometimes different from those of the control, which generally had the highest O-2, lowest CO2, and lowest ethanol. Shellac and the carnauba microemulsion also altered the volatile profile more than the control and the nanoemulsion did, especially for 'Unique' tangors. For 'Unique' tangors, the control and nanoemulsion ranked highest for tangerine flavor and had the least off-flavor at the end of storage. Among the coatings tested, the carnauba emulsions demonstrated less water loss, imparted more sustainable gloss, and caused less ethanol production than shellac, with the nanoemulsion exhibiting higher gloss measurements, less modifications of the atmosphere and volatile profile, and, consequently, better flavor compared with the microemulsion. Sao Paulo State Univ, Sch Pharmaceut Sci, BR-14800901 Araraquara, SP, Brazil ARS, US Hort Res Lab, USDA, 2001 South Rock Rd, Ft Pierce, FL 34945 USA Embrapa Instrumentacao Brazilian Agr Res Corp, BR-13560970 Sao Carlos, SP, Brazil Sao Paulo State Univ, Sch Pharmaceut Sci, BR-14800901 Araraquara, SP, Brazil CAPES: PDSE/201688881.132643/2016-01 FAPESP: 2016/23419-5 CNPq: 407956/2016-6

In-situ forming micro-particle (ISM) is an emulsion system that could change into micro-particulate matrices by phase separation of matrix former. In this research work, bleach shellac (BS) was used as the matrix forming agent to develop the doxycycline hyclate (DH)-loaded ISM and the different oils were used as the external phase of non-aqueous in oil emulsion. ISMs were prepared by using BS dissolved in dimethyl sulfoxide (DMSO), N-methyl pyrrolidone (NMP), or 2-pyrrolidone (PYR) as the internal phase and the external phase containing glycerol monosterate (GMS) in various oils including camellia oil, canola oil, olive oil, safflower oil, and sesame oil. The physical properties of ISMs using PYR as the solvent of the internal phase were tested including viscosity, in vitro micro-particle formation, injectability, drug release, surface topography, and antibacterial activity against Porphyrommonas gingivalis. All DH-loaded ISMs were easy to be injected through a needle and formed into micro-particles after exposure to phosphate buffer. The external oil phase reduced the friction between barrel and plunger of syringe and thus promoting easier injectability. The particular drug-loaded ISM prepared from safflower oil was largest, while that prepared from sesame oil was smallest and that of the others had no significant difference (p

V diplomskem delu je bila izdelana raziskava biopolimernega premaza iz šelaka in testirana raztopina SWANLAC ASL 10 na treh različnih vrstah kartona iz tujerodnih rastlin. Eden izmed ciljev je bil ugotoviti, v kolikšni meri je zgoraj navedena raztopina v kombinaciji s kartonom ustrezna za potrebe embaliranja. V teoretičnem delu so predstavljene osnovne funkcije embalaže, podrobneje opisani pojmi papir in karton ter postopek pridelave šelaka. Navedeni so tudi drugi proizvajalci biopolimernih premazov in možnosti, ki jih ponujajo. Za testiranje raztopine so uporabljene tri vrste kartonov iz različnih tujerodnih rastlin, in sicer rozge, dresnika in akacije, ki so nastali v okviru projekta APPLAUSE na Inštitutu za celulozo in papir v Ljubljani. Navedena so različna področja uporabe šelaka in opisana je raztopina, s katero so bili v eksperimentalnem delu kartoni premazani, posušeni, zrezani na predvidene formate in uporabljeni za nadaljnjo analizo. Testirane so bile osnovne, mehanske, površinske in strukturne lastnosti šestih različnih vzorcev, treh nepremazanih in treh premazanih z raztopino SWANLAC ASL 10. Vzorci so bili tudi potiskani z UV kapljičnim tiskalnikom, s čimer je bila preverjena kvaliteta tiska in njihova obstojnost na drgnenje. Po testiranju so bile preračunane povprečne vrednosti, standardni odkloni in variacijski koeficienti, meritve pa so bile med seboj podrobno primerjane. Rezultat diplomskega dela je testirana raztopina, ki bi jo v kombinaciji s specifičnimi vrstami kartonov lahko uporabljali za potrebe ustvarjanja bariere pri embaliranju in zmanjšali uporabo nerazgradljivih plastičnih premazov. In this thesis, research on biopolymer coating from shellac was performed and a solution of SWANLAC ASL 10 was tested on three different types of cardboard from non-native invasive plants. One of the objectives was to determine the extent to which the above solution in combination with cardboard is suitable for packaging purposes. The theoretical part presents the basic functions of packaging and describes the terms paper and cardboard, as well as the process of shellac production in more detail. Other manufacturers of biopolymer coatings and the options they offer are also listed. Three types of cartons from various non-native plants named twigs, knotweed and acacia, which were created within the project APPLAUSE at the Institute of Pulp and Paper in Ljubljana, were used to test the solution. Different areas of application of shellac were listed and the solution in which the cartons were coated, dried, cut into the intended format and used for further analysis, was described in detail. The basic, mechanical, surface and structural properties of six different samples — three without coating and three coatedwiththeSWANLACASL10solution— weretested.Thesampleswerealso printed with an UV droplet printer, checking the print quality and their abrasion resistance. After testing, average values, standard deviations and coefficients of variation were calculated, and the measurements were compared in detail. The result of the diploma thesis titled "Improving the Barrier Properties of Packaging Paper With Biopolymer Coatings" is a tested solution that could be used in combination with specific types of cardboard for the purpose of creating a barrier in packaging and reducing the use of non-degradable plastic coatings.

Copyright © 2021 The Author(s). To improve the mechanical properties of fast-growing Chinese fir (Cunnighamia lanceolate), expand its range of application, increase its value, and avoid the environmental pollution caused by impregnation with synthetic resin, Chinese fir was impregnated with a shellac solution. Since the shellac solution was difficult to penetrate into fast-growing Chinese fir, so microwave pretreatment was used to irradiate the wood to improve the permeability. This study investigated the effects of four factors, including the content of moisture in the wood before it was microwaved, the chamber pressure of microwave, the time of microwaving and the vacuum impregnation on the mechanical properties of Chinese fir wood. When the moisture content of wood before microwave was approximately 50%–60%, after microwaving and impregnation, the ultimate strength in static bending (modulus of rupture [MOR]) and strength in compression perpendicular to the grain (SCPG) of the wood increased significantly. A microwave time of 100 seconds was more effective at improving the MOR and SCPG of the wood. If the wood was microwaved for too short or long period of time, the microwave pretreatment was not effective. When the samples were immersed in shellac for a longer period, the MOR and SCPG of Chinese fir gradually increased, but when the wood was impregnated for more than 12 hours, the increases were not significant. After the shellac penetrated the Chinese fir wood, it spread on the inner wall surface of tracheid to form a shellac film and easily formed plug-like deposits in microcapillaries. The use of Fourier-transform infrared spectroscopy, scanning electron microscopy and scanning electron microscopy-energy dispersion x-ray indicated that the microwave pretreatment can destroy the pit membranes on tracheids and facilitate the ability of shellac to penetrate the channel. 2018 Forestry Science and Technology Research Project by Forestry Department of Fujian Province (No. 2018-26); Science and Technology Innovation Special Fund Project of Fujian Agriculture and Forestry University (CXZX2019111S); National Natural Science Foundation of China (31971593, 32071688); Natural Science Foundation of Fujian Province Department of Science and Technology (2019J01386).

Kesambi (Schleichera oleosa (Lour.) Merr.) is a host plant that becomes priority in lac culture in Indonesia. Shellac is one of the non-timber forest product commodities, which is potential to be one of foreign exchange sources. World demand of shellac is increasing throughout the year so that the improvement of shellac productivity is required to fulfill the demand. One of the alternatives is implementing the fertilization due to host plant quality improvement considering that host plant is the source of nutrient of shellac. The activity of fertilization aims to understand the effect of fertilization dosage to the improvement of the branch length as well as productivity of shellac in KPH Probolinggo. The greatest average value of branch length during three and six months, respectively were 66.48 cm and 83.24 cm. While, the greatest average value of shellac productivity was 84.29 g. The treatment of fertilization in different dosage to the kesambi (Schleichera oleosa (Lour.) Merr.) was not give significant effect to the length of branch as well as shellac productivity. Keywords: fertilization, Kesambi, Shellac

International audience; We conducted several tests on the stingless bee Melipona quadrifasciata aiming to determine the impact of the glue used for applying radio frequency identification (RFID) tags on this bee species. The study was organized in three experimental sets, in which we evaluated the effects of a synthetic glue, a natural glue (shellac), and the effects of the bee manipulation alone (control group). We performed (i) an in vitro experiment (bioassay), in which we tested five different experimental treatments in triplicate: chip plus synthetic glue, chip plus shellac, synthetic glue, shellac, and control, totaling 150 bees (n = 30 per treatment); (ii) field experiments, in which we tested the RFID tracking system composed of RFID tags, reading units, antennas, and circuit boards; and (iii) the morphological and histochemical analyses of the flight muscles of bees collected from each experimental treatment (n = 5 per treatment) at 48 h after the beginning of bioassay. Use of the natural glue, as opposed to the synthetic glue, promoted an increase of the bees’ longevity while inhibiting detrimental impacts on their foraging activities, as observed by both the bioassay and field experiments. We found negative responses to the synthetic glue treatment combined with the electronic tags, showing that the natural glue induces less morphological damage to the flight muscles of tagged stingless bees.

Green mold decay is considered as the main cause of postharvest loss in citrus fruits. With regard to safety concerns, this study was done to evaluate the efficacy of shellac as an edible coating and cinnamon essential oil (CEO) as alternative to synthetic fungicides to maintain quality of ‘Thomson navel’ oranges (Citrus sinensis L. Osbeck) inoculated with Penicillium digitatum spores. Fruit treated with distilled water (control), 1.5% ethanol (ET), 10% shellac (SH), commercial wax (CW), 0.5% commercial fungicide (Carbendazim), CF + CW, 0.3%, 0.4%, 0.5% and 0.6% CEO, 0.3%, 0.4%, 0.5% and 0.6% CEO + SH, SH enriched with 0.3%, 0.4%, 0.5% and 0.6% CEO (CEOSH) stored at 5 °C for up to 21 days. Fruit decay, weight loss, firmness, ascorbic acid were evaluated at 7 days interval, but scanning electron microscopy (SEM) images and sensory quality were evaluated at the end of storage. Shellac coating (10%) enriched with 0.5% CEO reduced weight loss by 52%, and firmness loss by 38%. The results showed that the incorporation of EOs into shellac could be a suitable treatment for maintenance of citrus fruit quality.

Linseed oil and shellac are natural, environmentally friendly materials with good water repellency. They were used to impregnate Chinese ash wood at room temperature (20 °C) using a vacuum-pressure procedure (consisting of three cycles of 0.01 MPa for 1.5 h and atmospheric pressure for 1.5 h) to improve the dimensional stability of wood. The effects of the impregnation treatment on wood color changes, dimensional stability, moisture absorption, and morphological characteristics were evaluated. The linseed oil and shellac treatment improved the dimensional stability of wood. Linseed oil and shellac displayed good permeability in Chinese ash wood, with weight gains of 21.7% and 19.0%, respectively, after impregnation. The swelling coefficients of treated wood in the tangential and radial directions decreased by 15 to 22%, indicating that impregnation improved the dimensional stability of wood. Linseed oil and shellac solidified and occluded the pits within the wood interior to prevent moisture absorption. This method can be used to improve the dimensional stability of a variety of wood products, such as buildings, furniture, and landscape architecture.

Bleached shellac, a widely used material in food processing and products, was deeply affected in terms of structures and properties by the bleaching method. In the present study, a marked difference was observed between the damage performances of sodium hypochlorite-bleached shellac (SHBS) and hydrogen peroxide-bleached shellac (HPBS). The main bleaching damage reactions of sodium hypochlorite were the addition of double bonds to generate chlorine and the oxidation of hydroxyl to form aldehydes or ketones. In the case of hydrogen peroxide, degradation of shellac resin was caused by the hydrolysis of ester bonds and the oxidation of hydroxyl groups to form aldehydes and ketones, as well as carboxylic acids with deep oxidation. Based on the structural characterization of shellac resin, the bleaching damages were affected by the bleaching agent via the oxidizable groups, such as the unsaturated double bonds, hydroxyl and aldehyde groups in cyclic terpenes, and fatty acid chains. The differences could be attributed to the action of sodium hypochlorite on the hydroxyl group of aldehyde or ketone. Conversely, hydrogen peroxide bleaching oxidized the hydroxyl group and aldehyde group to carboxylic acid and initiated the hydrolysis reaction of the ester bond of the shellac resin, leading to the degradation of the resin. Thus, understanding the mechanism underlying the bleaching damage could provide a scientific basis for the subsequent targeted regulation of bleaching damage.

The aim of this study was to develop the electrospun shellac (SHL) and hydroxypropyl cellulose (HPC) blended nanofibers for drug carrier application. The effects of polymer solution and electrospinning parameters, including SHL-HPC ratio, HPC concentration, applied voltage and flow rate, on the appearance of fibers were investigated. Based on the results, electrospun fiber was not obtained when a solution of HPC alone was employed. However, the fibers would be obviously fabricated as SHL was added to the HPC solution. An increase in the SHL ratio in SHL-HPC blended solution could accordingly lead to a remarkable enhance in the fiber diameter. In addition, the continuous nanofibers with less beads were gradually formulated when the HPC concentration was increased. The electrospinning parameters seemed to be significant. The elevation of infusion rate from 0.5 to 1 mL/h would contribute to the preparation of thick fibers with the diameters enlarging from 666.9 to 843.5 nm. With the applied voltage increasing from 15 to 30 kV during the electrospinning process, the fabrication of small nanofibers with the diameters reducing from 843.5 to 741.6 nm would be conducted. In this study, monolaurin (ML), a broad antimicrobial agent, was encapsulated into the SHL-HPC carrier for the purpose of drug delivery application. Regarding the result, the loaded concentration of ML could not be enhanced by introducing HPC to the SHL fibers.

With regard to the periodontal pocket application of in situ forming systems, the understanding the phase behavior after solidification owing to solvent movement could verify the deformability of specimen and its capacity to reside in the artificial periodontal pocket. The aim of this research was to investigate the phase behavior by determining mechanical properties as hardness and elasticity/plasticity ratio with texture analyzer for matrices obtained from drug-free and doxycycline hyclate (DX)-incorporated bleached shellac (BS) in situ forming gel (isg) and –microparticle (ism) after solvent exchange. The solvents for dissolving BS were 2-pyrrolidone (PYR), N-methyl pyrrolidone (NMP) and dimethyl sulfoxide (DMSO). The matrix from isg was less rough and bulge than that of isg. The order of mechanical hardness of transformed system prepared with different solvents was presented as PYR > NMP > DMSO, influenced by phase separation rate and porosity. The systems prepared with NMP and DMSO were more likely plastic or able to adapt its geometry to dynamic changes while that prepared with PYR was elastic. DX-incorporated ism matrix was still governed by the oil in external phase; thus, its consequence was reasonably plastic instead. XRD pattern indicated that the solvent type had no effect on the crystallinity of remained BS after solvent movement. SEM topography revealed sponge-like structure of isg prepared with DMSO and NMP whereas that prepared with PYR exhibited only initiated diminutive pores. The size and density of pores increased by time of isg using different solvents as following DMSO > NMP > PYR, whereas ism matrices had less pore density. The level of porosity of each matrix reflected the mechanical strength that a higher porous structure collapsed easily but a dense matrix considerably resisted to a compression.

Pd–Ni@SiO2 bimetallic nano-catalyst was prepared by chemical precipitation methodology intensified with ultrasonic wave. The influence of dosage of dispersant, precipitation temperature, stirring speed and ultrasonic intensity on the catalytic hydrodechlorination (CHDC) property for bleached shellac (BS) of the obtained catalysts was investigated in detail. The appearance morphology, phase composition and structure of the prepared catalysts were characterized with transmission electron microscopy (TEM), X-ray diffraction (XRD) and X-ray photoelectron spectra (XPS), and the specific surface area and the content of active components of the catalysts were tested by nitrogen adsorption according to Brunauer–Emmett–Teller (BET) method and inductively coupled plasma-atomic emission spectrometry (ICP-AES). The metal dispersion and mean particle size of metallic phase of the prepared catalysts were also determined with CO chemisorption. Results indicate that the optimal conditions for getting the precursors of catalysts is stirring and precipitating for 2 h at temperature of 35 °C under the speed of 500 r/min after dispersed for 7 min at ultrasonic intensity of 40% (480 W) while 3 wt% of the dosage of polyethylene glycol 6000 (PEG) was added at pH 11.5. Besides, the Pd–Ni/SiO2 bimetallic nano-catalyst prepared from the precursors by roasting at 500 °C for 2.5 h in air atmosphere followed by reducing at 500 °C for 2 h in the mixture atmosphere with hydrogen and nitrogen has uniform distribution of active ingredients with an average particle size of 3.57 nm, and the chlorine content of shellac dechlorinated with the prepared catalyst is 0.38 wt% from 1.95 wt%, achieving the demanding for application in food and pharmaceutical domains.

A crucial property of fibrous packaging paper for food is water resistance, while strength properties are also important. To improve these properties, several bio-coating solutions were applied as coatings on paper made of pineapple leaf pulp. The effects of beeswax, chitosan, shellac, alginate/gellan gum and beeswax–chitosan (1% chitosan+4%glycerol+30%beeswax) solutions on pineapple leaf pulp paper were assessed in relation to making biodegradable paper plates. The cooking time (120–180 min) of chemical pulping and the dose of pulp by moist weight (200, 250, and 300 g) to a paper frame (40 × 40 cm2) were also studied on making the paper samples. The papers were tested for their physical and mechanical properties. The optimal cooking time and dose of pulp by moist weight found were 180 min and 300 g of pulp per frame, respectively. The bio-coatings increased average grammage and thickness of paper, but gave density reduction from that of uncoated paper. Coating paper with beeswax–chitosan solution gave the longest absorbency time, followed in rank order by alginate/gellan gum, chitosan, beeswax and shellac. The maximum 5.9 kN/m2 tensile strength was found for paper coated with beeswax–chitosan solution before hot pressing. On comparing papers bio-coated before or after hot pressing, no difference was found in the degradable time with NaAlg/gellan coating, while such difference was observed with beeswax-chitosan coating. The results suggest beeswax–chitosan solution as the best among the alternatives tested, for coating paper to make biodegradable plates.

Renewable biobased porous aerogels with excellent biodegradability have versatile applications in oil/water separation, catalysis, and tissue engineering. However, processing of the porous matrix is challenging due to the high energy consumption and low efficiency from the fabrication procedures, such as freeze-drying or critical-drying of the hydrogel, which need to be improved. In the present study, natural amphiphilic oligomer shellac secreted by the lac Kerriar Lacca insect was employed to fabricate the porous template, which could self-assemble into a continuous rigid network with a hydrophobic core. Because of the hydrophobic core, the hydrated shellac network could be directly dried without collapse by the ambient air. The air-drying shellac aerogel presented a great mechanical property. The silane-coating treatment converted this shellac aerogel into a hydrophobic material that absorbed various organic solvents and oils. Also, this silane-coated shellac aerogel also could remove organic solvent or oil from the bottom or surface of the water. Notably, the saturable aerogel rapidly degraded in pH 14 and released the solvent absorbed by this matrix. This porous and hydrophobic matrix also could be applied as a filter that could connect with a vacuum pump to assemble a device for continuous collecting of oil from water. It also has great potential to be employed as a high-efficiency strategy to treat large scale oil spill issues. A new porous template composed of natural resin secreted by the insect was fabricated, and the whole fabrication process was green, low-cost, and energy saving. The surface of this template could be modified further to effectuate other processes, such as catalysis, heavy metal absorption, and tissue proliferation.

Background and purpose: Obesity is a global health problem and also a well-known risk for many diseases. Although some synthetic drugs have been marketed for the treatment of obesity, natural remedies may be considered as safe and cost-effective alternatives. Lac ( Kerria lacca Kerr) is a product from animal origin and is sold as seedlac or shellac. This drug is very famous among Unani practitioners for its antiobesity effects. The aim of the present study was to evaluate the antiobesity potential of lac in rats. Experimental approach: The effect of lac on rats fed with a high-fat diet (HFD) was investigated through determination of the changes in body weight, and serum levels of leptin. In addition, the effect of lac on total cholesterol, triglyceride (TG), low-density lipoprotein-cholesterol (LDL-C) and high-density lipoprotein-cholesterol (HDL-C) was studied. Male Wistar rats (170-220 g) were divided into eight groups; a control group with normal diet, the HFD group received a HFD, and the experimental groups received the HFD containing 0.1, 0.2, and 0.4% (w/w) of seedlac or 0.1, 0.2, and 0.4% (w/w) of shellac for 12 weeks. The body weight of each rat was measured once a week. At the end of the experiment, animals were sacrificed and serum concentrations of cholesterol, TG, low-density lipoprotein-cholesterol, high-density lipoprotein-cholesterol, and leptin were determined. Results: The study showed that seedlac and shellac significantly prevented increasing body weight and the levels of serum leptin were decreased in treated groups compared with HFD group. Also, shellac decreased TG level and both shellac and seedlac exerted a significant increase in HDL-C concentration. Conclusion and implications: Lac had weight-reducing properties and could be a promising alternative for controlling obesity.

The aim of this work was to investigate a possibility of preparing composite zein/natural resin (shellac and rosin) nanoparticles by antisolvent co–precipitation from their aqueous ethanol solutions. Influence of zein/resin mass ratio (1/0, 0.8/0.2, 0.5/0.5, 0.4/0.6 and 0/1) and pH (2–12) on particle size, d, and zeta potential, , of the prepared particles was studied. The functional properties of zein/rosin composite nanoparticles were evaluated by studying carvacrol encapsulation. It was shown that the antisolvent precipitation can be successfully used to prepare the shellac and rosin nanoparticles, as well as the composite zein/shellac and the zein/rosin nanoparticles. Colloidal properties, d and , of the obtained nanoparticles are influenced by the zein/ /resin mass ratio and the pH of nanoparticles’ dispersions. The isoelectric point of composite nanoparticles can be modulated by varying the zein/resin mass ratio. It was found that the zein/rosin nanoparticles are suitable for carvacrol encapsulation, where carvacrol release is enhanced by increasing the rosin share in the composite zein/rosin nanoparticles. [Project of the Serbian Ministry of Education, Science and Technological Development, Grant no. III 46010/3]

This study was aimed to prepare oleogels of whale spermaceti wax (WsWO) and lanolin wax (LnWO), and to compare them with well-known animal wax oleogels of shellac (ShWO) and beeswax (BsWO). WsWO, ShWO and BsWO were prepared at 5% (why) organogelator addition level, while LnWO was necessarily prepared at its minimum gelling concentration (C*) of 30% (w/w) addition level. All oleogels were posed high oil binding capacity and thermal reversibility. Melting peak temperatures were ordered as ShWO > BsWO > WsWO > LnWO by calorimetry. X-ray diffraction patterns indicated the presence of both Wand p type polymorphs, together with needle-like crystal morphology. Rheological analyses indicated that the stiffness of the gels were ordered as BsWO > WsWO > LnWO > ShWO. All showed good thixotropy, and thermal stability until 40 degrees C (ShWO until 80 degrees C). Finally, the sensory descriptive analysis indicated that LnWO had distinct negative sheep odor, but WsWO was quite similar to BsWO. Overall, LnWO determined to be not proper for food applications, but WsWO was shown to be a suitable oleogel for food applications.

Benefitting from the versatility and biocompatibility of food sourced materials, the construction of hybrid structures via their molecular interplay generates novel platforms with unexpected properties. In this work, two hydrophobic biomolecules were co-assembled into water-soluble amphiphiles at pH 7 by a facile pH-cycle approach. Wheat gluten proteins (WPs) and shellac were dissolved together at pH 12 followed by a one-step adjustment to pH 7, yielding nanospheres with a protein recovery over 90%. Structural characterization evidenced that shellac stiffened the protein backbones that were resistant against thermodynamically-favored folding. The reactions were proven to be initiated between the protein secondary structures and shellac, forming a relatively unfolded three-dimensional conformation during the acid-induced co-assembly. Silybin was employed as a hydrophobic bioactive model and was entrapped following the same procedure as the hybrid assembly, with a maximum loading of 102 mg g−1 hybrid. The bioavailability of silybin loaded in shellac–WP co-assemblies was improved as assessed by cell proliferation assays, due to the improved dispersity and cell internalization of the co-assemblies. The preparation method based on a simple pH manipulation may be applied to encapsulate various hydrophobic bioactive compounds, apart from the silybin explored in this study.

This paper describes the multi-analytical approach implemented for the study of the oil painting Il Venditore di Cerini made by Antonio Mancini in 1878. The research was carried out to characterize both the original stratigraphy and the alleged non-original varnish on the surface. SEM/EDS analysis showed the presence of pigments already detected in other paintings by Antonio Mancini. Multispectral imaging, DinoLite microscope, and FT-IR ATR spectroscopy revealed significant data regarding the invention of the “graticola” method—a technique implemented by Mancini to respect the proportions of the figures—also proving the presence of an aged layer of non-original shellac on the surface. The yellow/brownish tone of the varnish was hiding the real shapes of the figure, requiring a selective removal of the aged coating. The proposed cleaning systems were chosen among the green chemical alternatives present in the market, aiming at promoting a sustainable development in the Cultural Heritage field. The selection was made according to the Fd parameter of the cleaning systems—which defines the energy from dispersion forces between molecules—in relation to what is defined in the literature as the suitable Fd value for the removal of the shellac. The best-performing green cleaning system proved to be the Polar Varnish Rescue GEL—a gelled acetals mixture developed by YOCOCU APS—for its effectiveness in selectively remove the aged shellac while preserving the integrity of the original stratigraphy.

In this study, a coaxial electrospray process was used to produce nanoparticles, in which thymol was encapsulated in a core–shell of zein and shellac. We then investigated fluid velocity and solution concentrations on the electrospray. Scanning electron microscopy revealed that the thymol/zein/shellac particles prepared at a flow rate ratio of 0.6:0.3 mL/h were rounder with smaller diameters. The highest encapsulation efficiency of thymol was 81.34%, the average particle size was 606.53 nm, and the retention rate of thymol was 68.74% after 30 days. Moreover, we investigated the thermal stability, antimicrobial activity, and simulated gastrointestinal release curves of the nanoparticles. Finally, the nanoparticles were used as a coating for fresh-cut cantaloupe. Compared with the blank nanoparticle control group, the coating significantly extended the shelf life of cantaloupe to 16 days. Our results indicate that these nanoparticles have great potential for application in food preservation.

Self-repairing microcapsules prepared with melamine formaldehyde (MF) resin as wall material and shellac and waterborne coating as core material were added to waterborne coating to prepare a self-repairing coating. In order to explore the effect of the coating process on the performance of the waterborne coating on the basswood surface with microcapsules, the number of coating layers of primer and finish and the addition mode of the microcapsules were tested as influencing factors. The effects of different coating processes on the optical, mechanical, and liquid resistance of the basswood surface coating were investigated. The results showed that different coating processes had little effect on the color difference of the coating. When the coating process was two layers of primer and three layers of finish, and microcapsules were added to the finish, the minimum gloss of the basswood surface coating at 60° incident angle was 10.2%, and the best mechanical properties, liquid resistance, and comprehensive properties were achieved. Finally, the aging resistance and self-healing performance of the waterborne coating on the basswood surface prepared by this coating process were explored. The results showed that the waterborne coating had a certain repair effect on scratch damage. This paper lays a theoretical foundation for the practical application of self-healing microcapsules in wood-surface waterborne coatings.

The particles from gas saturated solutions (PGSS) process were performed to encapsulate lactofer-rin, an iron-binding milk glycoprotein, using supercritical carbon dioxide (scCO2). A natural en-teric polymer, shellac, was used as a coating material of lactoferrin carried out by the PGSS pro-cess. Conditions were optimized by applying different temperatures (20&ndash, 50 &deg, C) and pressures (8&ndash, 10 MPa) and the particles were evaluated for particle shape and size, lactoferrin encapsulation ef-ficiency, Fourier transform infrared (FTIR) spectroscopy to confirm lactoferrin entrapment and in vitro dissolution studies at different pH values. Particles with an average diameter of 75.5 &plusmn, 7 &mu, m were produced with encapsulation efficiency up to 71 &plusmn, 2%. Furthermore, particles that showed high stability in low pH (pH 1.2) and a sustained release over time (t2h = 75%) in higher pH (pH 7.4) suggested an effective encapsulation process for the protection of lactoferrin from gastric di-gestion.

Delivery systems play a crucial role in enhancing the activity of active substances; however, they require complex processing techniques and raw material design to achieve the desired properties. In this regard, raw materials that can be easily processed for different delivery systems are garnering attention. Among these raw materials, shellac, which is the only pharmaceutically used resin of animal origin, has been widely used in the development of various delivery systems owing to its pH responsiveness, biocompatibility, and degradability. Notably, shellac performs better on encapsulating hydrophobic active substances than other natural polymers, such as polysaccharides and proteins. In addition, specially designed shellac-based delivery systems can also be used for the codelivery of hydrophilic and hydrophobic active substances. Shellac is most widely used for oral administration, as shellac-based delivery systems can form a compact structure through hydrophobic interaction, protecting transported active substances from the harsh environment of the stomach to achieve targeted delivery in the small intestine or colon. In this review, the advantages of shellac in delivery systems are discussed in detail. Multiscale shellac-based delivery systems from the macroscale to nanoscale are comprehensively introduced, including matrix tablets, films, enteric coatings, hydrogels, microcapsules, microparticles (beads/spheres), nanoparticles, and nanofibers. Furthermore, the hotspots, deficiencies, and future perspectives of shellac-based delivery system development are also analyzed. We hoped this review will increase the understanding of shellac-based delivery systems and inspire their further development.

Peppermint essential oil is encapsulated by inverse ionotropic gelation in core–shell systems, composed of alginate (ALG) alone or alginate with shellac gum (SHL) and/or carrageenan (CRG). A mixture design approach is used to evaluate the correlation between the formulation composition and some properties of the final products. Immediately after the preparation, capsules appear rounded with a smooth and homogeneous surface, having a similar particle size ranging from 3.8 mm to 4.5 mm. The drying process, carried out at 40 °C in an oven for 3 h, reduces capsules’ diameters by at least 50% and has a negative impact on the shape of the systems because they lose their regular shape and their external membrane partially collapses. The peppermint essential oil content of dried capsules is between 14.84% and 33.75%. The swelling behaviour of the systems is affected by the composition of their outer shell. When the external membrane is composed of alginate and shellac gum, the capsule ability to swell is lower than that of the systems containing alginate alone. The swelling ratio reaches 31% for alginate capsules but does not exceed 21% if shellac is present. Differently, when the second polymer of the shell is carrageenan, the swelling ability increases as a function of polymer concentration and the swelling ratio reaches 360%. In the case of systems whose outer membrane is a polymeric ternary mixture, the swelling capacity increases or decreases according to the concentrations of the individual polymers. The obtained results suggest that carrageenan could be a useful excipient to increase the swelling behaviour of the systems, while shellac gum makes the system shell more hydrophobic. The use of a mixture design (i.e., the use of ternary diagrams and related calculations), in which each single component is chosen to provide specific properties to the final mixture, could be the right approach to develop improved formulations with a tailored essential oil release profile.