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关键词： A-glucosidase   Gluten-free   Antioxidant capacity  

摘要： Millet (Pennisetum glaucum) is a small gluten-free cereal originated from Africa that is not currently introduced in the Western diet. It is an interesting source of dietary fiber, vitamins, minerals, proteins and phenolic compounds superior to the most traditional consumed cereals. It is very effective crop adopted in no tilling farming system planted in a vast cultivated area in Brazil. Bread is a food product of high acceptance that is traditionally made from wheat, particularly from refined flours. However, it is known to present a high glycemic index and low levels of dietary fiber and naturally contains gluten proteins. The objective of this work was to develop whole grain bread using blends of raw and extruded flours from millet and to evaluate the physicochemical parameters in comparison to commercial whole bread products with and without gluten. The use of extrusion increased antioxidant capacity (215.2 +/- 1.9 mu M Trolox/g) and enzymatic inhibition (96.31 +/- 0.005) in relation to the product elaborated from raw flour. Millet is presented as potential food interesting for the production of bread considered in the diet of Brazilian population, particularly to those suffering from gluten allergy and diabetes.

关键词： Potato residue   particle size   physicochemical and functional properties   starch noodles   waste utilization  

摘要： The structural, physicochemical, and functional properties of potato residue with different mesh sizes (<180 mu m, <150 mu m, <106 mu m, <75 mu m, ultrafine) obtained from starch isolation were investigated, and its effects on the shear strength, tensile strength, cooking time, and in vitro digestibility of 5% potato residue-based starch noodles were further compared. The results showed that the protein, ash, dietary fiber, water holding capacity, and water solubility of fractionated potato residue were decreased with decreasing particle size, while the starch, fat, polyphenols, and alpha-amylase activity inhibition ratio were increased. Ultrafine particles exhibited the highest phenolic content (2.26 mg chlorogenic acid equivalent/g), glucose adsorption capacity (7.03 mmol/g), cholesterol adsorption capacity (16.54%), and better performance on starch noodles formulation. However, oil holding capacity and microstructure did not show any significant differences. Therefore, potato residues with desired particle sizes could be successfully used to develop fiber-enriched food products for reducing food waste.

关键词： Cattle   Corticosteroid treatments   Histological screening   Meat traits   Multivariate approach  

摘要： To preserve the Europe consumers' health, the use of glucocorticoids as growth promoters is prohibited in cattle fattening. In 2008, the Italian Ministry of Health associated to the official control a national monitoring plan based on the histological thymus analysis to identify animals illegally treated with corticosteroids. However, since corticosteroids are authorized and widely used for therapeutic purposes, it is necessary to verify whether the thymus histological test and some physicochemical traits in meat are able to discriminate doped calves from dexamethasone therapeutic treated ones. The aims of this study were (i) to establish whether the therapeutic and illicit corticosteroid treatments of calves could be differentiated through histological evaluation of thymus and by physicochemical meat traits;(ii) to identify a restricted number of physicochemical traits that could differentiate dexamethasone treated from untreated calves. Three groups of 15 calves each were included in this study: group dexamethasone therapeutic treatment treated with dexamethasone 21-phosphate disodium salt at a therapeutic dose (2 mg/ kg of live weight for three consecutive days);group dexamethasone anabolic treatment orally treated with dexamethasone 21-phosphate disodium salt according to a presumed anabolic protocol (0.4 mg/day per animal for 20 days);group placebo control treated with a placebo served as control. Results demonstrated that groups could be easily discriminated by thymus microscopy as well as by two meat markers, namely, cooking loss and shear firmness or Warner-Bratzler shear force. The combination of thymus microscopic features and meat physicochemical traits could be used as a practical, economic and accurate screening strategy to discriminate between meat from illegally and therapeutically treated calves. This new reliable and simple tool could contribute to identify animals treated with dexamethasone in those countries where glucocorticoids are illegally use

关键词： Antioxidants  

摘要： Beetroot (liquid or lyophilized) was added to whole milk stirred yogurt to evaluate its antioxidant activity, rheological (flow behavior and apparent viscosity), sensory (color, flavor, odor, texture, general acceptability, and preference of yogurt), and physicochemical (protein, fat, ash, humidity, syneresis, and pH) characteristics. Yogurt added with lyophilized beetroot extract encapsulated with maltodextrin had higher sensory quality and antioxidant activity (p < .05). The addition of encapsulated beetroot extract did not modify (p < .05) the rheological characteristics but significantly reduced syneresis and increased protein content and antioxidant activity (p < .05). These results indicated that encapsulated beetroot extracts represent an option to manufacture yogurt with added antioxidant activity. Practical applications In the last year, consumption of yogurt has increased due to its recognition as a functional food. Meanwhile, foods with antioxidant capacity have gain popularity among consumers. In this study, different beetroot extracts were added to yogurt as an antioxidant source while its rheology characteristics and acceptability were studied. Encapsulated beetroot extracts are promising ingredients to manufacture yogurt with added antioxidant activity. Therefore, we believe that this work can have an impact in advancing our understanding of how beetroot extracts added to yogurts changes their acceptance and physicochemical characteristics within the context of value-added in yogurt production.

关键词： Theobroma grandiflorum   Maximiliana maripa   Amazonian oils and fats   Fatty acids   Lipozyme TL IM   Interesterification  

摘要： The objective of this work was to evaluate the effect of enzymatic interesterification process in blends with different proportions (w:w) of cupuassu fat and inaja oil (80:20, 70:30, 60:40, 50:50 and 40:60). The interesterification reaction was carried out at 65 degrees C, agitation at 150 rpm, and enzyme concentration of 5% (w/w), for 6 h. Acidity index, melting point, consistency and solid fat content of the blends were characterized before and after the interesterification process. Fatty acid content was characterized in cupuassu fat and inaja oil and, nutritional quality indexes of atherogenicity (AI) and thrombogenicity (TI) were calculated. Enzymatic interesterification promoted a decrease in acidity (<0.6%) and changes in the blends' properties, making them suitable for food product preparation. All esterified blends (cupuassu seed fat:inaja pulp oil) presented suitable consistency properties, plasticity and spreadability to be used for the preparation of functional, table and soft table types of margarine and used in food preparation such as special fats.

关键词： One-pot   Quinoline   Stokes shift   Antibacterial   Molecular docking  

摘要： A donor-n-acceptor (D-n-A) chromophore, 2-amino-4-(9-ethyl-9H-carbazol-3-yl)-8-methoxy-5,6-dihydrobenzo[h] quinoline-3-carbonitrile (AEDQ) was synthesized from the condensation of 6-methoxy-3,4-dihydronaphthalen-1 (2H)-one, 9-ethyl-9H-carbazole-3-carbaldehyde, malononitrile and NH4OAc in ethanol. Spectroscopic techniques and elemental analysis were employed to establish the structure of AEDQ. Photophysical parameters and fluorescence quantum yield were calculated in the different polarity solvents to evaluate the interactions of the solvent with AEDQ chromophore. Further, the interaction of the AEDQ with cationic and anionic surfactants (CTAB, SDS) were also evaluated by using fluorescence spectroscopy techniques. The intensity of the fluorescence spectrum increased as the concentration of surfactants increased, suggesting that strong interaction occurs between AEDQ with surfactants, and this interaction arises from electrostatic forces. As a result, the AEDQ chromophore could be used to determine the CMC of surfactants. The disc diffusion and minimal inhibitory concentration (MIC) technique were used to test in-vitro antibacterial activity against Gram +ve and Gram -ve bacteria, and the results are compared with the standard drug, tetracycline. AEDQ also showed good ADMET, pharmacokinetics and drug-likeness properties, which are desirable for a good drug candidate. The molecule also fits well in the DNA gyrase A active pocket site with the binding free energy of -17.92 kcal/mol, which testifies its good antibacterial activity.

关键词： Grape tomato powder   Physicochemical properties   Shelf-life   Pork patties  

摘要： The objective of this study was to investigate antioxidant activities of various grape tomato powder (GTP) and then 0.25 and 0.5% oven-dried and freeze-dried GTP were applied to raw and cooked pork patties to investigate their physicochemical properties, texture, antioxidant activities, and antimicrobial activities. Oven-dried GTP dried at 100 degrees C had the highest 1,1-diphenyl-2-pycrylhydrazyl (DPPH) scavenging activity, ferric reducing power ability (FRPA), ferrous iron chelating activity (FICA) and total phenolic contents (TPCs) except for reference. pH and microbial counts of raw patties decreased after GTP was added. Raw and cooked patties showed decreases of 2-thiobarbituric acid reactive substances (TBARS), lightness values, and volatile basic nitrogen (VBN) values, while their redness and yellowness showed increases after the addition of GTP. Enterobacteriaceae did not show any growth for cooked treatments during storage. Addition of GTP improved antimicrobial and antioxidant activities of pork patties, and 0.5% oven-dried GTP showed the highest antioxidant activities among treatments during storage.

关键词： Secondary succession   Dominant fungi   Bacteria   Secondary forest   Grass   Shrub  

摘要： Based on long-term ecological research, microorganisms are sensitive to environmental changes in the process of ecosystem succession. However, few works have focused on the response of different groups of soil microorganisms to subalpine secondary succession and the driving forces behind the stepwise community development. To explore the changes in the microbial community structure and the driving mechanisms, we selected three replicated secondary succession gradients consisting of grass, shrub, different secondary forests (picea, pine and birch) and primary forest in a subalpine area in southwestern China. A high-throughput sequencing method was used to compare differences in the soil fungal and bacterial community structures. In combination with aboveground plant diversity and soil properties, the different mechanisms controlling the soil microbial community were revealed by the Mantel test. A two-way correlation network was also used to explore the connections among stages. The results show that the change in bacterial and fungal community structure was obvious, and these changes of bacteria were significantly correlated with soil acid phosphatase, LAP, soil moisture and aboveground vegetation communities during succession development in subalpine forests. Moreover, the fungal community was related to soil organic carbon, nitrogen, vegetation diversity, abundance and community structure. We also found that different dominant fungi play crucial roles in the succession sequence, and the relationship between soil microbes and vegetation is gradually simplified and stabilized. Our work suggests that both the relatively stable bacterial communities and the significantly changing fungal communities are notably associated with abiotic and biotic factors in secondary succession. As the ecosystem evolves, the dominant fungi obviously respond to succession and can successively establish close relationships with plants. Consequently, our results have important implications

关键词： Municipal waste   Landfill   Water   Impact   Leachate  

摘要： The paper aims to determine the most significant physicochemical indicators of the effects that a lined landfill in southern Poland has had on groundwater quality. The results of the tests of groundwater and leachate water from the landfill for the period 2009 to 2016 were subjected to a detailed statistical analysis based on the 10 physicochemical parameters. A factor analysis was conducted considering the European Union and national requirements for landfills using analytical and statistical tools. The leachate contamination indicators from a landfill were analysed to reveal their interaction with the groundwater. The assessment indicated that there was an elevated and statistically significantly higher electrical conductivity and copper and total organic carbon concentrations in groundwater hydraulically downgradient of the landfill. The assessment also indicated that there were significant differences in the correlations between chemical parameters downgradient of the landfill and that there was a trend of increasing concentrations of some chemical constituents in groundwater. The adverse effects of the landfill were due to the deposited amount of waste exceeding 10 Mg per day. The impact was noticeable despite low and decreasing concentrations of heavy metals (Hg, Cu, Cd, Pb and Zn) in the leachate. The deterioration of the chemical state of the groundwater in the landfill vicinity could result in the extended time of pollutant migration or mass transport in the irrigated soil medium due to the limited efficiency of the leachate intake system or sealing screen after more than 20 years of landfill operation.

关键词： Adlay seed   Noodle   Alkaline   Pasting properties   Quality properties  

摘要： Adlay seeds are rich in nutrients and can be processed into noodle ingredients. Adding kansui into the dough system is an effective strategy to improve the quality of coarse grain noodles. The effect of kansui (0-1.2%) on the physicochemical, structural properties and quality characteristics of adlay seed flour-fortified wheat noodles was investigated. Alkali increased G ' and G '' of the doughs, which is consistent with the extension of the dough development time and dough stability time. Kansui induced free -SH to participate in the formation of disulfide bonds of doughs, and the starch granules were surrounded by continuous gluten networks. In addition, the increased pasting temperature and reduced breakdown were consistent with the increased degree of order and degree of the double helix, which indicates that kansui could maintain the integrity of starch granules. In terms of noodle quality, the cooking loss and water absorption increased by 45% and decreased by 25%, respectively. Kansui also imparts a yellowish appearance, firm and elastic mouthfeel to the noodles. Pearson's correlation analysis showed that pasting characteristic values were significantly correlated with most parameters in the evaluation of noodle qualities. As a result, 0.6% kansui is the optimal formula to produce adlay seed-wheat noodles.