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关键词： Biofiltration   Butyric acid   Packing material   Genomic analysis   Limonene   Odor removal  

摘要： A multidisciplinary analysis based on physico-chemical, olfactometric and microbiological perspectives was performed to compare the biofiltration of air contaminated with limonene or butyric acid. Two biofilters were subjected to butyric acid gaseous streams: one was filled with wood chips and sewage sludge compost (BF B1) and the other with wood chips only (BF B-2). Similarly, two other biofilters were subjected to a gaseous stream containing limonene, with the same beds (BF L-1 and BF L-2, respectively). Although the biofilters fed with butyric acid received higher odor loads (280-3280 ouE/m2 center dot s for BF B-1 and 135-1460 ouE/m2 center dot s for BF B-2) than the biofilters treating limonene (30-170 ouE/m2 center dot s for BF L-1 and 15-130 ouE/m2 center dot s for BF L-2), the first systems achieved odor removal efficiencies greater than 90% during most of the biofiltration time, whereas in the limonene biofilters, these efficiencies never exceeded 70%. Regarding the packed beds, genomic analysis of the microbial communities showed a wider distribution of phyla (Proteobacteria, Firmicutes, Bacteroidetes, and Actinobacteria) in compost-wood biofilters than in wood chips systems where Proteobacteria was clearly predominant. This study reveals the importance of considering both the nature of the biofiltered compounds and the packed bed composition in biofiltration operations. (c) 2022 The Authors. Published by Elsevier Ltd on behalf of Institution of Chemical Engineers. CC_BY_4.0

关键词： vildagliptin   dipeptidylpeptidase-4 inhibitors   physicochemical properties   analysis methods  

摘要： Vildagliptin is an oral agent which is a member of a new class of hypoglycemic drugs, dipeptidylpeptidase-4 (DPP-4) inhibitors. This review presents the physicochemical properties of vildagliptin and assesses analysis methods for its estimation in substances, medicinal formulations, and biological media. These are chromatographic, spectrophotometric, electrochemical and other analysis methods. The material presented may be useful for developing new methods for analysis of medicinal formulations containing vildagliptin. The most widely used method for assay of vildagliptin is HPLC.

关键词： Whey   Electro-activation   Alkaline   Solubility   Emulsifying   Foaming  

摘要： The impact of alkaline electro-activation (EA) on the protein solubility, foaming, and emulsifying characteristics of whey was investigated. EA caused protein aggregation and conjugation. At low electric current and holding time, proteins aggregation through disulfide bonds was observed, whereas increasing currents and holding times caused proteins to conjugate with sugars such as lactose, lactulose and galactose. The EA process improved the protein solubility at the pH range of 4.0-7.0. Compared to untreated whey, which produced micron-sized and unstable emulsions at pH 3, whey samples treated under 750 mA and 24-48 h holding time formed nano-sized and stable emulsions at this pH. Furthermore, although both untreated and EA-whey produced stable emulsions at pH 7, those emulsions prepared with EA-whey had smaller particle size and were more stable against droplet flocculation. EA-treated whey tended to generate foams with significantly higher overrun and stability. The present study demonstrated that EA can enhance the functionality of whey.

关键词： lutein   nanoemulsions   stevioside   chickpea protein isolate   stability  

摘要： BACKGROUND Chickpea protein isolate (CPI) originating from chickpeas has the advantages of facilitating the stability of food emulsions. Stevioside (STE) exhibits a notable surface activity and can improve the water solubility of numerous hydrophobic nutrients. STE and protein mixtures show great potential as emulsions stabilizers. The present study aimed to prepare a novel nanoemulsion for encapsulating lutein (LUT) by ultrasonic homogenization using chickpea protein isolate-stevioside complex (CPI-STE) as a stabilizer and also to investigate the physicochemical characteristics. RESULTS The results obtained showed that different preparation conditions demonstrated significant influences on the physicochemical properties of CPI-STE-LUT nanoemulsions. Under the optimal condition, the average particle size of CPI-STE-LUT nanoemulsions was 195.1 nm, and the emulsifying and encapsulation efficiencies of lutein were 91.04% and 87.56%, respectively. CPI-STE-LUT nanoemulsions stabilized by CPI-STE could significantly increase the emulsifying and encapsulation efficiencies of lutein compared to that stabilized by CPI. Fourier transform infrared spectroscopy revealed that hydrogen bond was the main binding force of CPI and lutein, and there was a covalent bond between the two molecules. Furthermore, the stability of CPI-STE-LUT nanoemulsions in gastrointestinal phase was higher than that of CPI-LUT nanoemulsions, which could load lutein more effectively and be more resistant to digestive enzymes. CONCLUSION The present study reports the physicochemical characterization of CPI-STE-LUT nanoemulsions for the first time. CPI-STE-LUT nanoemulsions were characterized by a small average particle size lower than 200 nm, as well as high emulsifying and encapsulation efficiencies, and good stability. (c) 2021 Society of Chemical Industry.

关键词： Cyclodextrins  

摘要： In this work, we studied the formation of supramolecular inclusion complexes (pseudopolyrotaxanes) generated by the interactions between L35 Pluronic (PEO-PPO-PEO triblock copolymer) and hydroxyl propyl-modified cyclodextrins (HP-alpha-CD and HP-beta-CD). The structural characteristics of the L35/CD composites were investigated by X-ray diffraction spectroscopy, which highlighted the effective inclusion of the copolymer. The thermodynamic properties of the pseudopolyrotaxanes were determined through density and speed of sound experiments conducted on aqueous mixtures with various L35/CD compositions, while turbidimetric analyses allowed the investigation of the kinetics of the threading process of L35 polymeric chains within the cavity of the cyclodextrins. Both thermodynamic and kinetic features were explored at various temperatures (20, 25, 30 and 35 degrees C). According to the negative values of the Gibbs free energies, we observed that the formation of the pseudopolyrotaxanes is spontaneous for both cyclodextrins. Specifically, the inclusion process is more favoured for HP-beta-CD. This result was supported by the peculiar effects of the cyclodextrins on the interfacial characteristics of the copolymer at the air/water interface. In conclusion, this paper provides an extensive description of L35/HP-alpha-CD and L35/HP-beta-CD complexes that have potential as thermo-sensitive nanocarriers with controlled release properties.

关键词： biocompatibility   crosslinking   polysaccharides   radical polymerization  

摘要： Pullulan/polyHEMA cryogels were synthesized using epichlorohydrin (ECH) and ethylene glycol dimethacrylate (EGDMA) as crosslinkers. The dried cryogels were characterized by FTIR spectroscopy for chemical structure. Thermal analysis provided evidence for different microstructures of the samples synthesized. Water contact angle (WCA) value measured as 80.56 degrees for the pullulan/ECH/polyHEMA/polyEGDMA IPN sample reveal a more hydrophobic surface compared to the pullulan/ECH/polyHEMA graft copolymer with 18.32 degrees WCA. Scanning electron microscopy analysis of the IPN sample gives an average pore size 72.6 mu m, while the graft copolymer contains pores of average size of 100.5 mu m. Swelling and degradation kinetics studied by gravimetric method reveal that the samples act as degradable hydrogels in aqueous media with equilibrium swelling capacities of 75%-100% at pH 7.4. Cell viability of pullulan/ECH/polyHEMA/polyEGDMA IPN cryogel for colon carcinoma cell lines (HCT-116) investigated by MTT assay demonstrate that it is non-toxic and allows cell proliferation with 159 +/- 25.52% cell viability in 9 days.

关键词： depot injection   long acting injectables   intrinsic dissolution rate   dose-solubility   depot technology   sustained release   predictive models   nanoparticles   therapeutic index   ziprasidone  

摘要： The objective was to develop a model to a priori identify the most suitable depot technology for a candidate based upon its therapeutic index (TI), pharmacokinetics (PK), and physical chemical properties. A depot map of release rates needed to achieve target PK in TI against release rates predicted based on intrinsic dissolution rate (IDR) and particle size (PS) clearly identified three zones: (a) products and candidates around the line of identity for which suspension is the appropriate depot technology, (b) area to the right of line of identity in which depot candidates would require a controlled release technology such as PLGA microspheres since in vivo release rate needed for PK in TI is significantly lower than predicted based on IDR and PS, and (c) area to the left of the line of identity where IDR is not sufficient to achieve target in vivo release rate for PK in TI and hence enhanced dissolution is needed such as with nanoparticles. Dose-solubility technology map of approved depot products and candidates showed clusters of products around a depot technology such as suspensions and microspheres, for drugs with high dose/low solubility and low dose/high solubility compounds, respectively. Novel PK-based computational tool showed how all combinations of depot doses and release rate constants for a candidate can be calculated to achieve plasma levels within the TI bounded by minimum effective and minimum toxic concentrations (MEC and MTC). The PK predictions for several drugs such as estradiol, risperidone, medroxyprogesterone acetate (MPA), and ziprasidone showed how these predictions can guide scientists to target specific depot doses and release rates into the depot formulation. In parallel, IDR of depot compounds clearly showed differentiation of compounds by successful depot technologies to achieve target dose and duration. For drugs with IDR between 0.1 and 1 mg/h/cm(2), aqueous suspension has successfully delivered depot PK profile, while for candidates w

关键词： biomaterials   composites   drug delivery systems   gels   polysaccharides  

摘要： Natural bio-based materials used in wound dressings have been continuously developed in recent years, and have certain advantages in water retention, biocompatibility, and therapeutic properties. Konjac glucomannan (KGM) is a kind of plant polysaccharide with good cell compatibility and gel properties. Various gels obtained by modification of KGM through physical and chemical methods have great application potential in wound excipients. In the past few years, various KGM-based wound barrier materials such as hydrogels, xerogel, microspheres, films, and fibers have been continuously researched and developed. The combination of KGM and other polymers can improve the problem of poor mechanical properties and give it new functional properties, which is beneficial to the moisturizing of the wound surface and the release of drugs to promote wound healing. This article reviews the physicochemical properties of KGM and the latest developments in KGM-based composite gels, reveals the relationship between molecules in KGM-based composite gels, and looks forward to the research and development prospects of KGM-based composites in wound dressings.

关键词： Plasma treatment   Starch nanocrystals   Multiscale structure   Physicochemical properties   Rheology  

摘要： Non-thermal plasma has increasingly been used for surface modification of various materials as a novel green technology. In this study, we prepared potato starch nanocrystals (SNCs) assisted by dielectric barrier discharge plasma technology and investigated its multiscale structure, physicochemical properties and rheology. Plasma treatment did not change the morphology and crystalline pattern of SNCs but reduced the crystallinity. The amylose content, swelling power, gelatinization temperature, and apparent viscosity of SNCs decreased after the plasma process by depolymerizing the amylopectin branch chains and degrading SNCs molecules. Besides, plasma increased the rapidly digestible starch and resistant starch content. Changes in rheological properties of plasma treated SNCs suggested that the plasma process increased the flowing capacity. The effective structural and functional changes of plasma treated SNCs confirm that plasma technology has great potential for modification of SNCs.

关键词： Protein powder   Subcritical dimethyl ether extraction   Digestive properties   Rheological properties  

摘要： The process-related physicochemical, digestive and rheological properties of protein prepared by subcritical dimethyl ether extraction (SDEE) were comprehensively investigated and compared with those obtained by pHshift, to study the industrial potential of SDEE. Two different materials from tuna (meat and liver) were studied in parallel, and SDEE had similar effects on the proteins in them. The protein component was almost unchanged before and after SDEE, while the content of water-soluble protein and alkali-soluble protein was substantially reduced and increased after pH-shift, respectively. We also found that SDEE had superior ability to pH-shift to conserve light metals, remove lipids and heavy metals, and maintain protein structure. Furthermore, SDEE-produced protein powders were easier for humans to digest, and their gelation and emulsification were also superior to those prepared by pH-shift. The aforementioned results suggest that SDEE can remove more impurities, and the obtained protein has outstanding potential in industrial applications.