教学课程资源库 更多>>

关键词： Manufactured sand   Peat   Cement   Experimental study   Mechanical properties   Physico-chemical properties  

摘要： The traditional use of cement for soil stabilisation is challenged by peat due to the high organic content in peat and the associated unfavourable environmental and economic impacts. This study explores the potential and benefits of using manufactured sand, an economical, easily accessible and environmentally friendly construction material, with cement for peat stabilisation. Experiments were conducted with a view to investigating the optimal dosage of manufactured sand and cement, as evidenced by the improvement in the physico-chemical and mechanical qualities of stabilised peat. Based on the required strength of 1.00 MPa in engineering practice, an optimal configuration was determined with the ratio of manufactured sand to peat being 5:5, and the cement content 36.15%. At the optimal configuration, the unconfined compressive strength of stabilised peat was 2.33 times greater than the specimens without sand, and the void ratio was reduced from 1.72 of natural peat to less than 0.58. Optimal configuration can reduce cement dosage by 36.36%, hence carbon emissions by 36.36%, and costs by 38.28%. This study established that using manufactured sand with cement offered an economical, efficient and environmentally friendly engineering solution to peat stabilisation.

关键词： Antimicrobial activity   Chemotherapy   Sulfadiazine derivative   Thermal analysis  

摘要： Sulfadiazine is a drug famous for its anti-inflammatory, antimicrobial, and antitumor effects. Remarkably, its biological activity can be further enhanced upon incorporating a suitable metal ion. However, these metal-comprising complexes are not widely available. In the current study, a sulfadiazine Schiff base derivative was exploited as a ligand for synthesizing new complexes utilizing Cu(II), Co(II), Ni(II), Fe(III), and Cr(III) metals. The structural and analytical characteristics of the ligand and the newly prepared complexes were elucidated using various spectral and thermal investigations. Also, the biological activity of the ligand and the metal complexes, including the cytotoxic effect on normal cells and on liver malignant cells and the antimicrobial activity, was examined. The infrared spectra demonstrated that the ligand coordinated to all the added metal ions in a neutral form. It behaved in a bidentate manner in all mononuclear complexes. The new complexes exhibited octahedral geometry. Evaluating the biological activities revealed that the ligand and its novel metal-containing complexes had moderate antimicrobial activity, while the metal complexes, especially those comprising of Cr(III), Fe(III), and Cu(II), displayed a superior chemotherapeutic effect on HepG2 cell line in comparison to the ligand with very week or rare cytotoxic effects on normal human cells. Efficiently, new sulfadiazine Schiff base derivative-containing metal complexes with enhanced therapeutic potential were manufactured and could be applied on experimental models for the treatment of various types of infections and malignancies. (C) 2020 The Author(s). Published by Elsevier B.V. on behalf of King Saud University.

关键词： bioaccessibility   emulsion   lutein   physicochemical stability   vitamin E   whey protein isolate  

摘要： Lutein, as a bioactive substance, has the ability to decrease the risk of some chronic diseases, but the poor water solubility, chemical instability, and low bioaccessibility limit its wide application in foods. In this study, an emulsion-based delivery system stabilized by chlorogenic acid (CA)-whey protein isolate (WPI)-dextran (DEX) ternary conjugates was prepared and vitamin E (VE) was added to increase the chemical stability of lutein. Molecular weight and conformational information of ternary conjugates were obtained by sodium dodecyl sulphate-polyacrylamide gel electrophoresis, fluorescence spectroscopy, and Fourier transform infrared spectroscopy. o-Phthalaldehyde results suggested that the extent of glycation was 16.4% and 19.5% for (CA-WPI)-DEX and WPI-DEX conjugates, respectively. The physicochemical stability of lutein-enriched emulsions was evaluated under different environmental stresses and long-term storage. The obtained results showed that compared with emulsions stabilized by WPI alone or binary conjugates, ternary conjugates imparted emulsions high stability under different environmental stress conditions (ionic strength, freeze-thaw, and heat) and long-term storage (within 3 weeks). VE can effectively decrease the degradation rate of lutein without changing the physical stability of emulsions. Additionally, the lutein-enriched emulsions prepared by ternary conjugates and VE exhibited a relatively high bioaccessibility. Practical Application The ternary conjugates constructed in this paper has excellent physicochemical characteristics to stabilize emulsion, and can increase the water solubility of functional factors and reduce their degradation rate. Additionally, this conjugate was prepared by food-grade materials. Therefore, it can be used as emulsion-based delivery systems in food industrials.

关键词： Palmitic acid  

摘要： Antioxidant activity values of cookie samples were determined between 2.32% (0.0% (carob) and 76.75% (50% carob), while total phenolic contents of cookies vary between 36.59 (0.0% carob) and 123.61 mgGAE/100 g (100% carob). The brightness (L*) of the cookies with carob flour decreased. While palmitic acid contents of cookie samples change between 32.58 (50% carob) and 35.86% (100% carob), oleic acid contents of cookies were determined between 28.84 (50% carob) and 29.59% (60% carob). Gallic acid, 3,4-dihydroxybenzoic acid,(+)- catechin, and 1,2-dihydroxybenzene were the most common phenolic components in the cookie samples. 1,2-Dihydroxybenzene contents of cookie samples varied between 10.69 (control) and 32.27 mg/100 g (50% carob).While Ca contents of cookie samples change between 1,189.10 (control) and 3,286.82 mg/kg (100% carob), K contents of cookies were determined between 554.65 (control) and 7,402.83 mg/kg (100% carob). Taste, crispness, color, and fragrance values of cookies were partially decreased with the increase in the carob flour concentration. Practical applications Carob is a plant product used for sweetening purposes in the past and healing many diseases. Carob is one of the oldest and most useful plant species known on earth. Carob flour prevents crispness in pastry and muffins and prevents staling. In addition, carob flour can be used in various products, especially cocoa, because it contains natural sugar content, cholesterol-free, and is cheap. The products obtained from carob and carob are very useful in terms of health and are used in the treatment of various disorders. The fried pieces produced from carob fruit in recent years, especially in the common bakery products, confectionery products, and chocolate, are used instead of low-calorie confectionery products.

关键词： Oat beta-glucan   Optimisation   RSM   Gluten-free cake   Texture  

摘要： The demand for new gluten-free (GF) products is still very crucial issue in food industry. There is also a need for bioactive compounds and natural alternatives for food additives. For now, not only providing structure without gluten is major challenge, but also high sensory acceptance and nutritional value are on the top. This study is focused on the effect of high-purity oat beta-glucan as a structure-making agent on physicochemical and sensory properties of gluten-free yeast leavened cake. The response surface methodology (RSM) was used to set the design of the experiment. Water and oat beta-glucan were chosen as independent variables. Enzymatic extraction was conducted in order to obtain pure oat beta-glucan (approx. 85%). Physicochemical and microstructure analyses, and a consumer hedonic test were carried out to check the quality of the final product. As a last step, verification was undertaken to compare the predicted and experimental values of the results. The results showed that the optimisation process was crucial in obtaining high-quality, gluten-free yeast leavened cake. The optimised amounts of water and oat beta-glucan were 66.12% and 2.63% respectively. This proves that the application of oat beta-glucan to gluten-free products is possible and gives positive results in terms of texture, volume and sensory acceptance. Due to oat beta-glucan's pro-health benefits, the final product can be seen as a functional alternative for common gluten-free products in the market.

关键词： compatibility   critical care   dexmedetomidine   parenteral nutrition  

摘要： Background Dexmedetomidine is an alpha 2-agonist used as a sedative agent in the intensive care setting. Simultaneous administration of dexmedetomidine and parenteral nutrition (PN) may be required. The aim of this study was to evaluate the physicochemical compatibility of dexmedetomidine Y-site administered with PN. Methods Three PN and 3 dexmedetomidine solutions were compounded. The tested infusion rate for PN was 66 mL/h. For dexmedetomidine, we considered the initial and maximum infusion rates (0.7 and 1.4 mu g/kg/h) detailed in the data sheet. Taking this into account and considering a weight range of 55-95 kg, we tested 2 dexmedetomidine infusion rates (10 and 36 mL/h). The samples obtained were examined visually against light. pH was analyzed with a pH meter. Mean fat droplet diameter was determined by dynamic light scattering. Quantification of dexmedetomidine concentration was carried out by ultraperformance liquid chromatography-high-resolution mass spectrometry. For each PN-dexmedetomidine admixture, tests were performed in triplicate. Results No alterations were observed by visual inspection. Average pH was 6.25 +/- 0.01. Droplet diameter remained below 500 nm (298 +/- 10 nm for 10-mL/h rate and 303 +/- 5 nm for 36-mL/h rate). Dexmedetomidine concentrations at t = 0 were 519 +/- 31 ng/mL and 1391 +/- 90 ng/mL for 10- and 36-mL/h infusion rates, respectively. At t = 24 hours, the concentrations obtained were 494 +/- 22 and 1332 +/- 102 ng/mL, which translates into >= 90% of the initial concentrations. Conclusion Dexmedetomidine is physicochemically compatible with PN during simulated Y-site administration at the tested infusion rates.

关键词： Antioxidant capacity   apple peel powder   cookies   fibre   polyphenols   sensory quality  

摘要： Apple peel, a food industry by-product, is rich in fibre, polyphenols and minerals, and is a potentially attractive ingredient for bakery products. To evaluate the effect of wheat cookies enrichment with apple peel powder six types of cookies with increasing apple peel powder percentage (0%, 4%, 8%, 16%, 24% and 32%) were produced. The traits analysed were: pasting parameters;chemical properties (moisture, ash, lipid, protein, fibre and total polyphenols content);antioxidant capacity (2,2-diphenyl-1-picrylhydrazyl and ferric reducing antioxidant power methods);physical attributes (width, thickness, volume and CIE lab colour);and sensory characteristics (external appearance, internal structure, texture, odour, taste and aroma). Statistical analysis included analysis of variance followed by Fisher's least significant difference test (p < 0.05). The apple peel powder-enriched cookies had significantly higher moisture, ash, lipid, fibre, total polyphenols and antioxidant capacity than the control bread wheat cookies. The addition of apple peel powder did not modify the physical characteristics and improved the sensorial quality of the products. The addition of 24% apple peel powder gave the cookies with the best overall quality.

关键词： Synbiotics   Drying   Encapsulation   Microbial stability   Cell viability  

摘要： Encapsulation of probiotic bacteria requires precise control over a range of process parameters, all of which are technique-specific. The technology of encapsulation has received considerable attention in recent years, owing to the numerous ranges of benefits it offers, particularly in terms of quality retention, storage stability, and targeted delivery. In this research, spray-drying (SD) and spray-freeze-drying (SFD) techniques were used to encapsulate Lactobacillus plantarum (NCIM 2083). Fructo-oligosaccharide (FOS), whey protein (WP) and maltodextrin (MD) were used as encapsulating agents at different formulations. Changes in physicochemical properties were evaluated. FOS:WP:MD (2:0.5:0.5) gave higher encapsulation efficiencies of around 89.21% and 96.16% for SD and SFD, respectively. Probiotic stability was studied under simulated in-vitro digestion conditions and over the storage period of 60 days. SFD synbiotics showed better survivability during digestion;whereas, storage studies indicated around 0.95 fold increased retention of cell viability in SD synbiotics as compared to SFD.

关键词： Rooibos   Cold brew   Sensory profiling   Flavonoids   Aspalathin   Fe and Al content  

摘要： Cold brewing of rooibos tea has gained popularity, in particular in Japan, one of its major markets, due to the convenience of preparation. The sensory profile of traditional ('fermented') rooibos, prepared by regular brewing (5 min infused in freshly-boiled water) and served hot, is well described. However, no sensory profiling of cold brewed rooibos tea, rooibos tea served at ambient temperature, or green rooibos tea has been performed to date. In this study, the sensory profile of both fermented and green rooibos prepared by cold brewing (8 h at <5 degrees C), regular hot brewing and boiling (5 min), and consumed at ambient temperature (21 degrees C), were investigated. 'Rooibos woody' and 'fynbos-floral' aroma notes of fermented rooibos were unaffected by brewing procedure, but its cold brew was sweeter and less astringent than the other brews. The sensory profile of green rooibos, dominated by a 'hay/dried grass' aroma, bitter taste and astringency, was affected to a greater extent by brewing procedure, but mostly, cold and regular brews had similar aroma attribute intensities. Higher levels of flavonoids may explain the trends for astringency. Fe and Al were present in the highest levels in boiled brews, although at levels too low to impact on health.

关键词： functional food   green banana   hydrocolloids   starch   physical properties  

摘要： Asian noodles typically have high glycemic index, and an unbalanced diet heavily laden with carbohydrates has been linked to weight gain and *** from Japan is made from konjac glucomannan (KGM) and water and is widely known for its multiple health benefits and ability to promote satiety. However, it imparts negligible nutritional value due to its low energy content. In this study, the feasibility of making low calorie, gluten-free Shirataki noodles with improved nutritional value was shown by adding green banana flour (GBF), an underutilized subproduct of low commercial value and significance in the food industry. The optimal KGM-GBF noodles (with 6% w/w KGM, 35% w/w GBF) had 27% lower total energy content, 13% lower carbohydrate content, 5.4% higher fiber content, 2% higher ash content, and 80% hardness (as measured by texture profile analysis) when compared to commercial yellow alkaline wheat noodles. Multiple regression analysis showed that KGM level was a more influential factor than GBF level on the hardness of cooked KGM-GBF noodles (P< 0.01). The compatibility of GBF with KGM in noodle making lay in GBF's high gelatinizing and pasting temperatures, which allowed optimal KGM hydration during dough formation to develop the primary network structure in the noodles. Through this study, the potential of GBF as a functional food ingredient in product processing and nutrition enhancement was demonstrated. Practical Application The addition of green banana flour can improve the nutritional value and sensorial properties of konjac (Shirataki) noodles. This offers a gluten-free and low glycemic index alternative to wheat and starch noodles currently available commercially. A novel method of noodle-making to create KGM noodles, without the use of high alkalinity, was developed.