Coatings
·
2019
·Vol. 9
·期 11
·745
·
IF 2.33
Linyun Zhang,Chongxing Huang,Hui Zhao
In this work, some multilayer coatings (two-layer, four-layer or six-layer) based on pullulan and chitosan for protecting papayas were prepared by the layer-by-layer technique. The papayas were coated by immersion and stored at 25 °C, 50% relative humidity or up to 14 days. Uncoated and monolayer-coated papayas were used as controls. The pullulan/chitosan coatings decreased the papaya weight loss, softening, color change (b*, ΔE), and pH, retarded the fall of titratable acidity and vitamin C, and maintained respiratory rate and soluble solid contents. Sensory quality evaluation demonstrated that pullulan/chitosan coatings effectively preserved papaya flavor and overall acceptance. In general, the four-layer coatings provided the best fruit preservation. In conclusion, multilayer pullulan/chitosan coatings are efficient in maintaining the post-harvest quality and prolonging the shelf life of fresh papaya.Keywords:papaya;preservation;pullulan;chitosan;multilayer coating
研究领域:
食品科学
·
植物生理学
✓ 已验证
产品关联
DOI
高影响因子
MICROCHEMICAL JOURNAL
·
2019
·
IF 3.206
Qiqi Tan,Juan Qiao,Rongyue Zhang,Li Qi
Papaya juice protected copper nanoclusters was depicted for detection of serum l -histidine. The fluorescent probe was synthesized by using a simple “one pot” hydrothermal preparation strategy with papaya juice playing dual roles both as a green reductant and stabilizer. The excitation and emission peaks of the copper nanoclusters were at 400 nm and 490 nm, respectively. The fluorescence was turned-on in addition of l -histidine due to the enhanced surface electron density. The fluorescent intensity increased linearly with l -histidine concentration ranging from 2.0 to 50.0 µM. The proposed copper nanoclusters was further applied to determine l -histidine in rat serum after intraperitoneal injection.
研究领域:
生物化学
·
分析化学
✓ 已验证
产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF FOOD SCIENCE AND TECHNOLOGY
·
2022
·Vol. 57
·期 8
·5366-5375
·
IF 3.612
Jing Lv,Xinping Lin,Wenqing Wang,Wenhuan Xu,Caichan Li,Chaofan Ji,Huipeng Liang,Shengjie Li,Sufang Zhang,Beiwei Zhu
Summary Suanzhayu is a traditional Chinese fermented fish that often faces a long fermentation time (about 1 month) and unstable quality. This study evaluated the combined effects of papain and Lactiplantibacillus plantarum 1-24-LJ, a selected starter culture, on the quality of Suanzhayu . The addition of L. plantarum and/or papain increased the content of alcohols, esters, ketones and umami amino acids (UAAs), but decreased the content of bitter amino acids (BAAs). Besides, Lactobacillus might play a role in reducing harmful bacteria and BAAs content and increasing UAAs content, while Lactococcus and Weissella contributed to the characteristic flavour of Suanzhayu . Overall, no significant improvement in sensory quality was observed with the addition of papain alone, while better quality and faster fermentation processes were obtained with the addition of L. plantarum 1-24-LJ alone or in combination with papain. The results contribute to quality control in Suanzhayu production and the selection of starter cultures.
研究领域:
食品科学
·
微生物学
✓ 已验证
DOI
高影响因子
INDUSTRIAL CROPS AND PRODUCTS
·
2024
·
IF 5.6
Kun Li,Jiaqi Zhang,Yifan Li,Zirong Li,Jun Wang,Yuanyuan Yu,Qiang Wang,Ping Wang
The application of protease as a biocatalyst for the anti-felting finishing of wool has been widely explored. However, commercial proteases tend to hydrolyze the non-keratinized proteins in the cell membrane complex (CMC) layer while removing wool scales, resulting in excessive hydrolysis and unacceptable fiber damage. Herein, chitosan oligosaccharide (COS) was covalently grafted to papain using carbodiimide/N-hydroxysuccinimide (EDC/NHS) to prepare a less-destructive modified protease of Pap-COS. Subsequently, one-bath anti-felting finishing of wool was carried out using reducing agent and Pap-COS, aiming at achieving low shrinkage and reduced strength loss. The results reveal that Pap-COS achieved a larger particle size than native papain, accompanied by a prolongation of its half-life and a decrease in the thermal inactivation rate, demonstrating improved stability. Under the same incubation conditions, the felting shrinkage of wool fabrics treated with papain and Pap-COS was similar (approximately 5 %). In contrast, native papain caused a 20.82 % decrease in fabric strength, while Pap-COS resulted in a substantially lower decrease (8.10 %), meeting the requirements of commercial woolen products. Furthermore, the dyeing performance and wearability of the Pap-COS-treated wool fabrics were also dramatically improved. The present work provides an alternative for eco-friendly shrink-resistant finishing of woolen textiles in wool industry.
研究领域:
纺织科学与工程
·
生物化学与分子生物学
✓ 已验证
产品关联
DOI
高影响因子
Food Science and Technology
·
2022
·
IF 2.602
CHEN Jian-Peng,WANG Yue,ZHANG Xu-Yang,SUN Ping,WU Zheng-Fang,SHANG Ya-Fang,YANG Shao-Hua,MA Yi-Long,WEI Zhao-Jun
Xuan-Mugua is a Chinese traditional fruit and is mainly preserved by air drying. To explore the effect of temperature on the drying property and quality of the fruits, they were sliced and dried at 60-90 °C. The results indicated that the drying time shortened from 150 to 80 min with the increasing temperature and the minimal time was found at 90 °C. The total phenolic content and antioxidant activity generally decreased by 5.09-18.27% at higher temperature (90 °C) and their maximums respectively appeared at 60 and 80 °C. Compared with the medium temperatures (60 and 70°C), the phenolic profiles changed obviously at higher temperatures (80 and 90 °C), and a transformation of chlorogenic acid was detected; besides, with the increasing temperature, the main phenolics including catechin and chlorogenic acid respectively decreased by 29.3% and 18.4%. Taking the above findings together, 70 °C should be the proper temperature to dry Xuan-Mugua fruits.
研究领域:
食品科学
·
植物化学
✓ 已验证
产品关联
DOI
高影响因子
Food Packaging and Shelf Life
·
2025
·
IF 10.6
Fengyan Liang,Jinwen Geng,Ziming Yang,Wanqi Cen,Miaoyu Zhao,Xunting Huang,Changbin Wei,Puwang Li,Kaidong Liu
Amphiphilic chitosan (DA-CS-AG) was synthesized and incorporated with ursolic acid (UA) to develop an active coating film. Characterization techniques confirmed the preparation of DA-CS-AG, and UA was successfully entrapped in the active coating films. With the weight ratios of UA to DA-CS-AG increasing from 1:20, 2:20–4:20, the coating films exhibited increased thickness, improved water resistance, higher tensile strength, and enhanced antioxidant and antibacterial properties. As the UA/DA-CS-AG weight ratio increased from 1:20–2:20, the films ’ UV-shielding capability, water vapor barrier properties, and elastic properties increased. However, these properties deteriorated when the weight ratio increased to 4:20. Preservation experiments of papaya fruits demonstrated that UA/DA-CS-AG-2 coating films delayed the ripening of papaya at 25 º C for 16 days based on appearance, color changes, quality indexes, and sensory evaluation. In conclusion, these active coating films can serve as packaging materials for fruits and vegetables.
研究领域:
食品科学
·
材料科学
·
植物学
✓ 已验证
产品关联
DOI
高影响因子
ULTRASONICS SONOCHEMISTRY
·
2016
·
IF 4.556
Liping Feng,Yanping Cao,Duoxia Xu,Sasa You,Fu Han
The aim of the study was to investigate the impact of sodium alginate (ALG) pretreated by ultrasound on the enzyme activity, structure, conformation and molecular weight and distribution of papain. ALG solutions were pretreated with ultrasound at varying power (0.05, 0.15, 0.25, 0.35, 0.45 W/cm 2 ), 135 kHz, 50 °C for 20 min. The maximum relative activity of papain increased by 10.53% when mixed with ALG pretreated by ultrasound at 0.25 W/cm 2 , compared with the untreated ALG. The influence of ultrasound pretreated ALG on the conformation and secondary structure of papain were assessed by fluorescence spectroscopy and circular dichroism spectroscopy. The fluorescence spectra revealed that ultrasound pretreated ALG increased the number of tryptophan on papain surface, especially at 0.25 W/cm 2 . It indicated that ultrasound pretreatment induced molecular unfolding, causing the exposure of more hydrophobic groups and regions from inside to the outside of the papain molecules. Furthermore, ultrasound pretreated ALG resulted in minor changes in the secondary structure of the papain. The content of α-helix was slightly increased after ultrasound pretreatment and no significant change was observed at different ultrasound powers. ALG pretreated by ultrasound enhanced the stability of the secondary structure of papain, especially at 0.25 W/cm 2 . The free sulfhydryl (SH) content of papain was slightly increased and then decreased with the increase of ultrasonic power. The maximum content of free SH was observed at 0.25 W/cm 2 , under which the content of the free SH increased by 6.36% compared with the untreated ALG. Dynamic light scattering showed that the effect of ultrasound treatment was mainly the homogenization of the ALG particles in the mixed dispersion. The gel permeation chromatography coupled with the multi-angle laser light scattering photometer analysis showed that the molecular weight ( M w ) of papain/ALG was decreased and then increased with the ultrasonic pretreatment. Results demonstrated that the activity of immobilized papain improved by ultrasonic pretreatment was mainly caused by the variation of the conformation of papain and the effect of interactions between papain and ALG. This study is important to explain the intermolecular interactions of biopolymers and the mechanism of enzyme immobilization treated by ultrasound in improving the enzymatic activity. As expected, ALG pretreated by appropriate ultrasound is promising as a bioactive compound carrier in the field of immobilized enzyme.
研究领域:
生物化学
·
酶工程
·
食品科学
✓ 已验证
DOI
高影响因子
RSC Advances
·
2018
·Vol. 8
·期 5
·2357-2364
·
IF 2.936
Jianyun Yu,Xinxin Chen,Min Jiang,Anming Wang,Linlin Yang,Xiaolin Pei,Pengfei Zhang,Stephen Gang Wu
To develop an efficient and green immobilized biocatalyst for promiscuous catalysis which has a broad scope of applications, hybrid nanoflower (hNF) confined papain as a biocatalyst has been proposed and characterized in this study. hNFs were firstly prepared through mixing CuSO4 aqueous solution with papain in phosphate saline (PBS) at room temperature. The resulting hNFs were characterized by SEM and verified through a hydrolysis reaction with N-benzoyl-DL-arginine amide as substrate. Under optimal conditions, this nano-biocatalyst demonstrated a 15-fold hydrolytic activity compared with papain of free form, along with better thermal stability. A series of reaction factors (reaction temperature, time, and solvent) have been investigated for Knoevenagel condensation reactions with hNFs as catalyst. At optimal conditions, product yield of the hNFs catalyzed reaction was 1.3 fold higher than that of the free enzyme with benzaldehyde and acetylacetone as substrates. A few aldehydes and methylene compounds have also been used to test the generality and scope of this new enzymatic promiscuity. To sum up, the obtained hNFs demonstrate better catalytic properties than free papain and the inorganic metal-salt crystal can function as both support and promotor in biocatalysis.
研究领域:
生物化学
·
材料科学
·
酶工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Food Chemistry-X
·
2022
·
IF 6.443
Hongbin Chen,Hetong Lin,Xuanjing Jiang,Mengshi Lin,Zhongqi Fan
The influence of melatonin treatment on the quality and chilling injury of guavas during storage at 4 ± 1 °C were evaluated. Compared with control group, fruit of guava cv. Xiguahong exposed to various concentrations (50, 100, 150, and 200 μmol/L) of melatonin showed a significantly lower fruit respiration rate, weight loss, cell membrane permeability, and chilling injury index, but a higher commercially acceptable fruit rate, higher peel L*, h ° value, and chlorophyll content. Melatonin treatment also delayed the decreases of fruit firmness, sucrose, total soluble sugar, vitamin C, titratable acidity, and total soluble solids. These data indicate that melatonin treatment could increase chilling tolerance and retain quality of cold-stored guavas. Among various concentrations of melatonin treatment, 100 μmol/L melatonin-treated guavas showed the preferable quality properties and lowest chilling injury index. Thus, melatonin may be a novel method of postharvest handling to enhance cold resistance and extend storage-life of cold-stored guava fruit.
研究领域:
植物生理学
·
食品科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Waste and Biomass Valorization
·
2018
·Vol. 10
·期 6
·1755-1766
·
IF 1.874
Pathak Pranav D.,Mandavgane Sachin A.,Kulkarni Bhaskar D.
Papaya is a popular fruit consumed worldwide and well-known for its food and nutritional values. It is used in food industries for the production of jams, jellies, etc. As a result, these industries generate huge amounts of papaya peel (PP) and seeds as by-products, which are typically considered a waste, and thus discarded. However, our current investigation indicates that PP is a valuable source of bioactive compounds, which can be converted into many value-added products. In this article, we review the physicochemical composition and valorization of PP. PP can be utilized to obtain many value-added products by fermentation (e.g., biofuels, adsorbents, dietary fibers, biomedicine, biomaterials). The biorefinery approach for PP will definitely increase the value of this waste by producing an array of value-added products and achieving zero waste generation.
研究领域:
食品科学
·
生物技术
·
环境科学
✓ 已验证
DOI
高影响因子
SN Applied Sciences
·
2021
·Vol. 3
·期 3
·1-9
·
IF 0
Ma Yinzheng,Wen Yingying,Chen Jinping,Zhang Yunxia,Zhang Haiying,Sui Jinlei,Yi Guohui,He Xiaowen
A rapid and sensitive headspace gas chromatography-mass spectrometry (HS-GC–MS) method was established for the determination of benzyl isothiocyanate (BITC) in the peel, pulp, and seeds of Carica papaya Linn. Tween 80 solution with a concentration of 0.002% ( w/v ) was chosen as a headspace medium for solving the poor solubility of BITC in water without using organic solvents and ensuring high headspace efficiencies. Extraction parameters had been evaluated and optimized by using an orthogonal design with an OA 9 (3 4 ) table. Optimal headspace conditions were obtained when vials were equilibrated at 80 °C for 20 min at a stirring speed of 375 rpm. The calibration curve obtained by using GC–MS was linear in a concentration range of 10–320 ng/mL. The recoveries of peel, pulp, and seeds ranged from 97.3 to 100.6% with RSDs less than 3.0%. The method is simple, rapid, sensitive, and environmentally friendly. It is suitable for analyzing BITC in papaya fruit and is expected to have important application potential in the extraction of water-insoluble volatile components in foods, plants, medicines, and other samples.
研究领域:
食品科学
·
分析化学
·
植物学
✓ 已验证
产品关联
DOI
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
·
2018
·
IF 3.909
Yan-Jie Gu,Min-Liang Zhu,Yan-Li Li,Chun-Hua Xiong
A new type of magnetic metal chelating carrier (PCMM-IDA-Cu 2+ ) was prepared for the immobilization of papain, using chitosan as raw material, nano Fe 3 O 4 as magnetic material, SiO 2 as porogen, iminodiacetic acid (IDA) as a chelating ligand, and binding with transition metal ion (Cu 2+ ). The resulting products were well characterized by optical microscopy, scanning electron microscopy (SEM), vibrating sample magnetometer (VSM), Fourier transform infrared spectroscopy (FTIR) and thermogravimetric analysis (TGA). The BBD (Box-Behnken Design) of RSM (Response Surface Methodology) was applied to analyze the optimum enzyme immobilization conditions. The results showed that the enzyme immobilization capacity was 94.18 mg/g of PCMM-IDA-Cu 2+ , with 7.976 U/mg of relative immobilized enzyme activity under the optimum conditions (pH 6.73, 1.56 mg enzyme/15.0 mg carrier, 30.9 °C), and the recovery of enzyme activity was reached 87.21%. Compared with the free papain, the immobilized papain displayed enhanced enzyme activity, superior enzymatic properties, good operational stability and reusability. It is worth mentioning that the novel carriers exhibited selectively biological adsorption capacity, and this technique is an alternative method for the immobilization of enzyme, making the process more efficient and economic.
研究领域:
生物化学
·
酶工程
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）