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关键词： cohesivity   extrusion force   hyaluronic acid   rheology   skin quality improvement   swelling degree  

摘要： In addition to clinical research on the efficacy and compatibility of injectable hyaluronic acid (HA) based fillers, ample in vitro research on the physicochemical properties of these materials is published. Different HA-based product ranges are also available as skin quality boosters (SQBs) to improve skin quality. The aim of this study is to investigate the physicochemical properties of specific HAs for improving skin quality, as, to the best of the authors' knowledge, no data is published on this topic to date. This paper may provide a better understanding of clinical performance and differentiation between these SQBs. Five HA injectable hydrogels (Belotero Revive, Juvederm Volite, Restylane Skinbooster Vital, Viscoderm Hydrobooster, and Profilho) from the SQB product ranges of different companies and manufacturing technologies are investigated for their extrusion force, swelling degree, rheological performance, and cohesivity. There are significant differences in extrusion force, swelling degree, rheological performance, and cohesivity between the assessed SQBs. HA concentration (mg mL(-1)) exhibits statistically significant positive correlations with extrusion force, swelling degree, tan delta, and cohesivity. This study provides a physicochemical characterization of different SQBs and information to improve understanding of this type of product.

关键词： Hwangtae   Fumigation   Aluminum phosphide   Phosphine   Residue  

摘要： This study detected phosphine residues and the qualitative effect of phosphine fumigation on Hwangtae (yellowish-dried Alaska pollock). Four types of Hwangtae products commercially purchased were investigated to assess phosphine residue. Hwangtae was fumigated at both laboratory scale, at an aluminum phosphide rate of 33.6 g/m(3), and large scale (1.68 g/m(3)) to evaluate phosphine residue and dissipation. Further, nutritional composition analyses between pre- and post-fumigated Hwangtae were conducted. The concentration of phosphine residues was lower than the detection limit (0.005 mg/kg) in all Hwangtae products. After fumigation in laboratory scale, phosphine residue was 2.47 mg/kg, and after fumigation in large scale, the residue was 3.25 mg/kg. After 3-d aeration in the open air, there was no residue detected from fumigated Hwangtae. Nutritional composition, including proximate, mineral, and amino acid compositions, did not differ (P > 0.05) between pre- and post-fumigated Hwangtae. Overall, Hwangtae did not demonstrate a phosphine residue problem after the proper aeration process, and phosphine did not alter the nutritional composition, suggesting the use of phosphine as a fumigant to protect Hwangtae from insect pests.

关键词： Edible coatings   Decay   Enzyme activity   Antioxidant activity   Ascorbic acid  

摘要： Effect of edible coatings of gum Arabic, carrageenan and xanthan gum containing lemon grass essential oil 1% w/ v on postharvest quality of strawberry was studied under refrigeration for a period of 12 days. Results showed all the three coatings maintained fruit quality parameters during storage compared to control. Among all the coatings, carrageenan coated fruits showed delayed weight loss (10.1 to 8%), decay percentage (78.42 to 14.29%), retained ascorbic acid (0.15 to 0.27 g kg(-1)), antioxidant activity (18.17 to 25.85%), firmness (9.07 to 12.43 N), L* (32.38 to 40.42), a* (16.08 to 17.22) and b* (27.36 to 33.54). Carrageenan gum also showed lowest cellulase activity (0.03 units h 1 mg protein 1), pectin methylesterase activity (1.13 A620 min 1 mg protein(-1)) and beta-galactosidase activity (0.51 mu mol min(-1) mg protein 1), while showed maximum reduction in polygalacturonase activity (0.07 units h(-1) mg protein (-1)) at the end of storage. Carrageenan gum was found effective in retention of anthocyanins and phenolic compounds during storage. Coatings loaded with antimicrobial agent inhibited psychrophilic bacteria, yeast and mold growth. It is concluded that carrageenan gum could better retain strawberry quality up to 12 days under refrigeration.

关键词： Tropical tubers   Freeze-drying   Fresh cooking   Starch   Flours   Physicochemical   Thermal properties  

摘要： Flours and starches extracted from the tropical tubers underwent freeze-drying and cooking in comparison with fresh cooking. Freeze-dried and cooked starch (FDS) granules were found to have different shapes and collapsed arrangement whereas freshly cooked starch (FCS) granules had the least varied structures. The freeze-dried flours had larger structures compared to freshly cooked flours. The physicochemical parameters were high in Dioscorea esculenta (DE)-FDS, followed by Amorphophallus paeoniifolius (AP)-FDS and other samples whereas D. alata (DA)-FCS had the lowest, whereas flours followed similar trend. FDS (42.1%) had the highest solubility index and swelling power whereas FCS (11.1%) showed the lowest. The syneresis and light transmittance levels were higher in FDS and FDF. The freeze dried flour and starch showed higher onset (T-0), peak (T-P), and conclusion (T-C) temperature than fresh cooked samples. The variations in IR spectra, thermal properties, and crystalline index were termed as differential function of physicochemical characteristics, structural changes that resulted from freeze drying, and cooking treatment employed. (c) 2021 Elsevier B.V. All rights reserved.

关键词： Hairtail (Trichiurus haumela)   Eugenol-chitosan nanoemulsion   Edible coating  

摘要： Effects of the eugenol-chitosan nanoemulsion as an edible coating on the quality of hairtail (Trichiurus haumela) during storage at 4 degrees C were evaluated. For all samples, such parameters as pH, thiobarbituric acid (TBA), total volatile basic nitrogen (TVB-N), water holding capacity (WHC), electrical conductivity (EC), total bacteria count (TVC) and sensory were examined periodically. The results demonstrated that eugenol-chitosan nanoemulsion coating showed better preservative effects than chitosan nanoemulsion alone. Therefore, a coating based on eugenol-chitosan nanoemulsion could be regarded as an effective food-grade biopreservative to maintain the quality of hairtail fish and prolong its shelf life during chilled storage.

关键词： Tetrastigma hemsleyanum   Starch   Resistant starch   Physicochemical properties  

摘要： Physicochemical characteristics of starch isolated from Tetrastigma hemsleyanum Diels et Gilg (T. hemsleyanum) tuber root of 4 different origins were firstly analyzed in this study. The starch granules of T. hemsleyanum tuber root were oval or globular, showed unimodal distribution with average size of 21.66-28.79 mu m. T. hemsleyanum starch had typical B-type diffraction pattern. T. hemsleyanum root was rich in starch, and apparent amylose content ranged from 39.82% to 47.67%. The amylopectin chain profiles showed that over 50% of the total detectable chains had degree of polymerization (DP) with 13-24. T. hemsleyanum tuber root had high RS content, which reached up to 61.44% in flour and 68.81% in isolated starch. After cooking, the RS content decreased, but was still high up to 7.52% in flour and 9.93% in isolated starch. The peak gelatinization temperature of T. hemsleyanum starch ranged from 68.12 to 74.42 degrees C. The peak viscosity of T. hemsleyanum flour and starch ranged from 778 to 1258 cP and 1577 to 2009 cP respectively. The results indicate that T. hemsleyanum is a potential source for novel starch with high resistant starch and provide some guides for comprehensive utilization of T. hemsleyanum starch in food and pharmaceuticals industry. (c) 2021 Elsevier B.V. All rights reserved.

关键词： Composite hydrogel   Marine polysaccharide   Fucoidan  

摘要： Marine polysaccharide-based hydrogels have drawn much attention for diversified biomedical applications owing to their excellent (bio)physicochemical properties. In the present work, a series of marine polysaccharidebased hydrogels composed of chitosan, alginate, or fucoidan are prepared via a facile chemical cross-linking approach in an alkali/urea aqueous system. The prepared hydrogels possess tunable microporous architecture, swelling, and biodegradable properties by changing the components and proportions of marine polysaccharides. Importantly, the developed hydrogels are mechanically robust and the maximum compressive stress is up to 28.37 +/- 4.63 kPa. Furthermore, the composite hydrogels exhibit excellent cytocompatibility, blood compatibility, and histocompatibility. When implanted subcutaneously in rats, the hydrogels containing fucoidan inhibit the inflammatory response of surrounding tissue. Thus, the designed composite hydrogels are promising bioscaffolds in biomedical applications.

关键词： Guar gum   14-butanediol diglycidyl ether   Hydrogel   Crosslinking density   Drug delivery  

摘要： The aim of the present study was to obtain a better and safer galactomannan-based material for drug release applications. A novel epoxy-crosslinked galactomannan hydrogel (EGH) was prepared from guar gum using 1,4butanediol diglycidyl ether as a crosslinking agent. The diffusion rate constant of water molecules in freeze-dried EGH positively correlated with water uptake/equilibrium swelling rate (WU/ESR), and the water molecules participated in Fickian diffusion. The ESR, WU/ESR, and bovine serum albumin (BSA) loading capacity of a customized EGH with a crosslinking density of 48.9% were 48.7 +/- 0.15 g/g, 95.3%, and 56.4 mg/g, respectively. The release of BSA from freeze-dried EGH was affected by the WU/ESR and the pH;the release equilibrium time was -40 h at pH 1.2, decreasing to -24 h at pH 7.4. Furthermore, the cumulative release rate increased from 63.5% to 80.7% and the t50 decreased from 59 to 41 min upon changing from the acidic to basic pH. The release process conformed to the Ritger-Peppas and Hixson-Crowell models, and represented Fickian diffusion and chain relaxation. The EGH showed no cytotoxicity toward HeLa cells. Together, these results demonstrate the properties of a novel galactomannan-based hydrogel that can potentially be employed as a vehicle for drug delivery.

关键词： Blackberry fruit   Extraction solvent   Antioxidant activity   Hypoglycemic activity   AGEs formation  

摘要： In this study, hot water, 0.1 M HCl and 0.1 M NaOH and 0.1 M NaCl solution were separately used for extraction of blackberry polysaccharides (BPs: Hw, Ac, Al and Na). The physicochemical properties and biological activities were then investigated and compared. Results showed that the extraction yield, molecular weight, monosaccharide composition, particle size, triple-helical structure, surface morphology and rheological properties of BPs were greatly affected by extraction solvents. Bioactivity assays implied that the four BPs showed that the polysaccharides (Hw and Na) with higher molecular weight had stronger antioxidant and alpha-glucosidase inhibitory activity. Moreover, antiglycated assay indicated that BPs with higher molecular weight and higher content of galacturonic acid possessed better inhibition of AGEs formation. These results suggested that the higher molecular weight of blackberry polysaccharide could be developed as a beneficial bioactive ingredient for diabetes mellitus and complications. (c) 2021 Elsevier B.V. All rights reserved.

关键词： Microwave-ultrasound and/or toughening   A- and B-type wheat starch granule   In vitro digestibility  

摘要： In this study, the effect of microwave-ultrasound or/and toughening treatment on the physicochemical, structural properties, and in vitro digestibility of A-and B-type granules isolated from wheat starch were investigated. From the SEM, microwave-ultrasound and toughening treatment (MU-T) led to the appearance of irregular and disrupted structure significantly and an increment in the resistant starch content of A-and B-type granule. Furthermore, the MU-T starch possessed the lowest swelling power, light transmittance, and gelatinization temperature range (Tc -To) and the highest Delta H. After MU-T, the relative crystallinity (RC) of X-ray pattern, Fourier transform infrared ratio of 1047/1022 cm(-1), and the content of double helix and single helix of C-13 CP/MAS NMR had increased significantly. In particular, there was a difference in the content of RS and SDS between A starch granules and B-starch granules as well as their changes after modification (from 69.305% to 82.93 for A starch and form 74.97% to 88.17 for B-starch, respectively), which was a similar trend with RC and helix content. This study indicated that, for both A-type granule and B-type granule starches, microwave-ultrasound and toughening treated samples had unique properties compared to singly modified starches. (C) 2021 Elsevier B.V. All rights reserved.