Intense Brown Color Research Articles

Development of gluten-free biscuits made from composite flour of cassava (Manihot esculenta Crantz) and cowpea (Vigna unguiculata (L.) Walp)

Biscuit is a ready-to-eat, convenient, and inexpensive food product. It is one of many baked products often make with wheat flour. Nonetheless, people with gluten intolerance cannot consume wheat flour. In this research, gluten-free biscuits made with a composite flour of cassava and cowpea with different ratio (90:10, 80:20, and 70:30). The result has shown that gluten-free biscuits with 70:30 gave the highest dietary fibre content (20.54±0.32%). The combination of 70:30 cassava flour (CF) and cowpea flour (CPF) gave lightness (L*) value 60.58±1.22 means darker colour to biscuits with 4.13±0.07% of moisture content. From the scoring test, the panellists were perceived F3 as having less crunchy texture (3.51±1.20), less intensity of foreign aroma (2.60±0.87), brown colour (4.37±1.10), and slight foreign taste detected (3.01±1.10). From the hedonic test result, the panellists were neutral in the acceptances of texture (4.44±1.37), foreign aroma (4.94±1.20), and colour (4.96±1.2). The panellists have slightly liked the overall acceptance and foreign taste of gluten-free biscuits within the value of 5.01±0.97 and 5.04±1.20. Thus, the study suggests that F3 consist of 70:30 CF and CPF is selected as the best formulation to make gluten-free biscuits.

Optical, electrical, and catalytic (photo-and sono-) properties of indium doped γ-Bi2O3 with Sillenite structure

The exotic structure and properties exhibited by the metastable solids are exemplified adequately in the materials chemistry area. In this report, metastable γ-Bi2O3 has been stabilized without adding any impurity by the auto-combustion method and compared with the changes in structure and optical property brought out by the inclusion of In3+ ions. Compositions doped with indium (7 and 10 mol% in place of bismuth) resulted in stoichiometric Sillenite-type structures as revealed by their powder X-ray diffraction patterns, FTIR, and Raman spectral measurements. The pale yellow γ-Bi2O3 acquired pale brown coloration on indium inclusion, and the intensities varied with varying indium content. Optical bandgap reduction from 2.63 (pure γ-Bi2O3) to 2.41 eV occurred when 10 mol% of indium was doped in place of bismuth. The formation of non-stoichiometric Sillenite structures was noticed in samples with higher indium concentrations (up to 50 mol%). The non-stoichiometric samples displayed intense brown color and showed a drastic reduction in the optical bandgap, reaching values as low as 1.57 eV (50 mol% indium doped sample). From XPS analysis and red-ox titrations, nearly 5% of oxygen excess was estimated for the non-stoichiometric samples doped with indium. The BET surface area of indium doped non-stoichiometric Sillenites (126 m2/g) was higher than indium doped stoichiometric Sillenites (74 m2/g). The oxygen ion conductivity studies of pure γ-Bi2O3 and indium doped non-stoichiometric Sillenites revealed a marginal rise in conductivity with indium inclusion.

Treatment of biomethanated wastewater with a quaternised chitosan

AbstractThe use of 2‐hydroxypropyl‐3‐trimethylammonium chitosan chloride (HTCC) to decrease the intense brown colour and COD of biomethanated wastewater was investigated. The effects of pH on the rheology of HTCC solutions and their ability to decolourise were examined. HTCC had a positive zeta potential that decreased as pH increased. Decolourisation and COD reduction were decreased slightly when the pH of the HTCC solution was increased from 4 to 9. Variation of pH of the wastewater from 6 to10 did not affect decolourisation. FT‐IR spectra of HTCC and its flocs isolated after flocculation indicated that interaction of the major anionic colourant occurred at sites near the cationic quaternary nitrogen of HTCC. Acidic solutions of HTCC were very effective flocculants, producing >80% decolourisation and >50% COD reduction. Prevention of pollution caused by the discharge of the enormous volumes of biomethanated wastewater that are generated worldwide could be facilitated by its treatment with non‐toxic HTCC.

Isolasi dan Karakterisasi Jamur Pelapuk Putih Pendegradasi Lignin dari Limbah Cair Pulp dan Kayu Lapuk Eukaliptus (Eucalyptus sp)

Lignin is an organic polymer compound that is difficult to degrade in the environment because of its very complex structure consisting of an aromatic ring group and three carbons in the side chain. This exploratory study aims to determine whether white rot fungi isolated from wastewater from eucalypt pulp and weathered wood are lignolytic and the ability of the isolates to degrade tannins as an approach in the lignin degradation process. The experimental design is divided into two stages, namely: 1) Isolation of fungi that have the ability to degrade tannins quantitatively and qualitatively as well as characterization of fungi morphologically (macroscopic and microscopic). 2) Testing the ability of superior white rot fungus isolates in degrading tannins at concentrations of 0.5%, 1%, 1.5% and 2% of tannins. The brown zone formed in white rot fungal isolates was measured the zone diameter and intensity of the brown color. The results of this study indicate that of the 29 isolates obtained, there were five superior isolates capable of degrading tannins, namely isolates LD06, LD07, BE01.3, BE01.4 and BE02.2. BE01.3 was isolated at 2% tannin concentration, the second largest diameter of the brown zone after LD06 isolate and the highest brown color intensity level three with a slightly dark brown color intensity, namely slightly blackish brown.
 Keywords: Isolation, characterization, white rot fungi, tannins, lignin degradation

Application of the descriptor-profile method in modeling the recipes of a preserved food using sprouted grain and malt extract

The article reflects the possibilities of using the descriptor-profile method in modeling recipes of functional food products taking into account the consumer preferences. Preserved foods using sprouted bare-grained oats or wheat and barley-malt extract served as samples for research. The simulation of the consumer preferences of the preserved product was carried out using a descriptor-profile method of tasting analysis. There were thirty-two features of descriptors identified for assessing organoleptic indicators and emotional customers’ perception of the product. A visual model of the consumer preferences of the preserved product was formed. The intensity and significance of each descriptor were determined. Influence of share of sprouted grain and malt extract on consumer preferences of preserved product was studied. Increasing the share of sprouted grain in the product reduced the coverage of the grain with the extract, the pallor and hardness of the grain, the intensity of brown color and the presence of malt-apple aroma. An "ideal" portrait of the product has been developed taking into account the strengths and weaknesses of the product, allowing to design organoleptic indicators at the stage of product development. High consumer preferences of the preserved product – a harmonious sweet taste with slight sourness, malt-apple-honey aroma, moderate grain hardness, lack of bitterness, – were achieved with 40% – 50% sprouted grain and 50% – 60% extract.

Energy recovery from biomethanation of vinasse and its potential application in ozonation post-treatment for removal of biorecalcitrant organic compounds

Vinasse is characterized by a high chemical oxygen demand (COD) and dark brown colour, which requires abatement before disposal to prevent the pollution of receiving streams. Anaerobic digestion (AD) usually applied for vinasse treatment can only reduce the COD with the colour remaining unabated. This study investigated the feasibility of combining AD and ozonation for vinasse treatment. The AD process alone achieved high COD removal of 95 %, at a best organic loading rate of 15 kgCOD/m3/d. However, the anaerobic effluent still had an intense dark brown colour caused by a considerable amount of residual biorecalcitrant COD of 4.5 g/L. The ozonation post-treatment of the anaerobic effluent removed 80 % of the colour with up to 92 % ozone transfer at optimal parameters of pH 4, substrate dilution factor of 2, and 90 mg/L/min ozone dosage. Kinetic analysis showed that for a constant feed flow combined system, the ratio of the anaerobic reactor unit to the ozonation reactor unit is recommended to be 20:1. Also, from energy analysis, application of the bioenergy produced from AD to supplement the total energy requirement of the combined system could lead to 50 % savings on energy, and a carbon dioxide emission reduction of 122 kg CO2/m3 of vinasse treated. The combined system is thus a promising technology for vinasse treatment and can contribute to combating greenhouse gas emissions.

Transcriptomic analysis of the liver in aged laying hens with different intensity of brown eggshell color.

ObjectiveEggshell color is an important indicator of egg quality for consumers, especially for brown eggs. Various factors related to laying hens and their environment affect brown eggshell coloration. However, there have been no studies investigating hepatic functions of laying hens with variable intensity of brown eggshell color. Therefore, this study was aimed to identify potential factors affecting brown eggshell coloration in aged laying hens at the hepatic transcriptomic level.MethodsFive hundred 92-wk-old Hy-line Brown laying hens were screened to select laying hens with different intensity of brown eggshell color based on eggshell color fans. Based on eggshell color scores, hens with dark brown eggshells (DBE; eggshell color fan score = 14.8) and hens with light brown eggshells (LBE; eggshell color fan score = 9.7) were finally selected for the liver sampling. We performed RNA-seq analysis using the liver samples through the paired-end sequencing libraries. Differentially expressed genes (DEGs) profiling was carried out to identify their biological meaning by bioinformatics.ResultsA total of 290 DEGs were identified with 196 being up-regulated and 94 being down-regulated in DBE groups as compared to LBE groups. The Kyoto encyclopedia of genes and genomes (KEGG) analysis revealed that these DEGs belong to several biological pathways including herpes simplex infection (toll-like receptor 3 [TLR3], cyclin-dependent kinase 1, etc.) and influenza A (TLR3, radical S-adenosyl methionine domain containing 2, myxovirus [influenza virus] resistance 1, etc.). Genes related to stress response (ceremide kinase like) and nutrient metabolism (phosphoenolpyruvate carboxy-kinase 1, methylmalonic aciduria [cobalamin deficiency] cblB type, glycine receptor alpha 2, solute carrier family 7 member 11, etc.) were also identified to be differentially expressed.ConclusionThe current results provide new insights regarding hepatic molecular functions related to different intensity of brown eggshell color in aged laying hens. These insights will contribute to future studies aiming to optimize brown eggshell coloration in aged laying hens.

Platinum nanoflowers with peroxidase-like property in a dual immunoassay for dehydroepiandrosterone.

Platinum nanoflowers (PtNFs) were utilized in a competitive enzyme-linked immunosorbent assay (ELISA) and in a lateral flow immunoassay (LFIA) for superior peroxidase-like activity and intense brown color, respectively. PtNFs were linked to the polyclonal antibody (pAb) to form the pAb-PtNFs probes for the dual immunoassay. Based on optimized pAb-PtNF probes, both enzyme-linked immunosorbent assay (PtNFs-ELISA) and lateral flow immunoassay (PtNFs-LFIA) perform very well. The absorbance at 450nm decreases linearly in the DHEA concentration range 2.1 to 118.1ngmL-1, and the limit of detection is 1.3ngmL-1 and theIC50 value is 15.7ngmL-1 of PtNFs-ELISA. The visual cut-off value of PtNFs-LFIA is 10.0ngmL-1. The average recoveries from spiked samples range from 95.0 to 108.9% with a coefficient ofvariation below 12.2%. Excellent recoveries and correlation between the two methods were observed. Furthermore, the designed immunosensors exhibited good selectivity, confirming a broad development prospect in DHEA monitoring. Graphical Abstract.

Culture Media Composition and Reduction Potential Optimization of Mycelia-free Filtrate for the Biosynthesis of Silver Nanoparticles Using the Fungus Tritirachium oryzae W5H

Background: A major focus of nanotechnology concerns is the expansion of the optimization of nanomaterials in purity, size and dispersity. Methods: In the current work, a two-step AgNP synthesis process was optimized at the mycelia-DI water suspension and AgNP formation reaction levels. Results: Biomass filtrate from the fungal strain Tritirachium oryzae W5H was able to reduce silver nitrate into AgNPs after a 72 h reaction, as indicated by the development of intense brown color and by UV-vis spectra. The biosynthesis ability of AgNPs was markedly better in the presence of a single carbon and nitrogen source in the culture medium compared to multiple sources of carbon and nitrogen. The optimization results of AgNP formation were indifferent between the two steps and were 20 g biomass, 40°C, pH 7.0, 96 h and 1.0 mM AgNO3. The TEM images of the prepared AgNPs illustrated the presence of 7-75 nm, monodispersed and spherical- to ovular-shaped Ag nanoparticles. Conclusion: The present work highlights the importance of investigating the process parameters by which the reductant mycelia-free filtrate was prepared. In addition, we explored the promising antibacterial action of the prepared AgNPs against bacterial infections.

Ohmic heating technology in dulce de leche: Physical and thermal profile, microstructure, and modeling of crystal size growth

The effect of ohmic heating (OH) parameters (voltage gradient, 2, 4, 6, 8, and 10 V cm−1) on the quality properties of dulce de leche (DL) was evaluated. Optical (L*, C*, and BI), rheological (flow curves and oscillatory tests) and thermal (differential scanning calorimetry) parameters as well as microstructure (optical microscopy) and modeling of the crystal size growth were evaluated during the storage time (60 days at 25 °C). Overall, OH processing resulted in lower optical (C* and BI) parameters, indicating a product with a lower intensity of caramel brown color. For the rheological assays, it was observed a decrease in the viscosity and consistency of the products (lower k values and higher n and G’ values). Finally, the OH-treated products presented higher numbers of lactose crystals of smaller size. The impact of OH was dependent on the voltage gradient, with a more pronounced effect on the product submitted to high electric field (10 V cm−1). Overall, OH is an interesting technology to be used in DL processing, being recommended the utilization of 8 V cm−1 of voltage gradient due to the better-quality properties.

Development of power­efficient and environmentally safe coffee product technologies

Based on the energy and environmental audit, analysis of material flows, energy conversion, emissions into atmosphere and lithosphere in the production of instant coffee was carried out. To raise energy efficiency and reduce environmental burden, innovative flow diagrams and equipment for waste processing and production of new coffee products have been developed. Experimental modeling was carried out: kinetics of microwave extraction of water-soluble substances and oil from coffee slurry; hydraulics of the extractant flow through cassettes of the microwave extractor. The experimental data were summarized in the form of a criterion equation. As a result of experimental modeling of the extraction kinetics, it was found that the duration of the process in a microwave field is approximately 20 times less than in a thermostat. The microwave field affects the extraction rate to a greater extent than the process temperature. The growth of microwave power results in a more than the two-fold rise of the yield of extractives from a coffee slurry. Specification of the microwave oil extractor was defined. The extractor sample was tested at a specific power of 180...240 W/kg in the mode of boiling extractant. Ethanol (93...96 % concentration) was used as an extractant. As a result of the tests, a high-quality coffee oil was obtained. It is characterized by a pronounced aroma, coffee taste and an intense dark brown color. Flow diagram of pre-extraction of coffee from slurry was worked out. Additional extraction of water-soluble extractive substances from coffee slurry increased the extract yield by 10...12 %. The temperature regime of extraction was significantly reduced plus duration and energy intensity of the process were reduced. An innovative flow diagram has been developed for the production of liquid coffee concentrate as a basis for coffee-based drinks ready for immediate use. The concentration of solids is 50...65 %

초산용액으로 증자한 흑삼의 ginsenoside Rg3 발현 최적화

This study aimed to obtain high quality black ginseng with a high content of the ginsenoside Rg3 and melanoidins and low benzopyrene content via nine steaming-drying cycles. The steaming-drying of ginseng was carried out at low pH, and the heat treatment conditions were set to gradually decrease. The steaming-drying conditions were evaluated using response surface methodology. The coefficients of determination (R2) of the models were 0.8926–0.9744 (p<0.05) for the dependent parameters. The response surface for the intensity of the brown color of the black ginseng showed a maximum point at which the brown color intensity was 3.39 (OD at 420 nm) at a mean steaming time of 155.25 min and a mean drying temperature of 57.56°C. The response surface for the ginsenoside Rg3 content of black ginseng showed a saddle point with a maximum ginsenoside Rg3 content of 6.26 mg/g at a mean steaming time of 177.72 min and a mean drying temperature of 65.46°C. However, the response surface for the benzopyrene content of black ginseng showed a maximum point, with the lowest benzopyrene content of 0.22 μg/kg occurring at a mean steaming time of 60.97 min and a mean drying temperature of 56.42°C. The optimal conditions were determined to be a mean steaming time of 175 min and at a mean drying temperature of 68°C; black ginseng manufactured using these conditions yielded a brown color intensity of 2.72 and a Rg3 content of 6.20 mg/g, with a low benzopyrene content of 0.29 μg/kg.

Evaluation of Stable Morphological Traits in Soybean Collection Samples for Determination of Standard Varieties

For identification of varieties, it is desirable to use genetically predetermined traits that are decisive for the varietal identification of the distinguishing characteristics of the varieties production and new genotypes for selection. The presence a complete evaluation of the selection samples a particular crop is the basis for the formation of informative databases characteristics the varieties of standards used in plant examination to determine the level of expression a characteristic particular genotype according to the code of their manifestation. For the 20 traits we used to identify, we identified 6 least volatile, highly trait-stable traits over the years of study to identify. These are: “coloring of the pubescence of the main stem”, “the size of the lateral leaf”, “the intensity of green leaf color”, “flower color”, “the intensity of brown bean color”, “basic color of the seed coat”. The other 14 traits are highly variable and unstable among varieties, but may be significant under certain conditions. According to the results of the research we have determined the conformity of the collection varieties by code graduation. In the study, we selected varieties with corresponding codes of attributes of the reference varieties the UPOV technique. On the basic of the color the pubescence of the main stem, 36% varieties are with grey stem pubescence. Among the standards: Apache, Alaric, Talon according to the grey color of the pubescence, we identified varieties Zolotysta, Ozzie, Diona. The 2947 564/84, Stepnaya-90, Knyazhna. The lateral leaf size is a sign that affects the increase in green mass of plants and subsequently on productivity. Graduation of the sign small size of leaf had varieties: Zuma, Ksenya; middle – Heinong 37, Yuh-30; large – 2947 564/84, Vinni, DSS 2504. The following is a sign of the intensity of leaf plate, which is divided by gradation into light, moderate and dark. Among our samples with a light degree of color, we can distinguish Diona, Sribna Ruta, and Zuma. For varieties with moderate gradation of color are selected: Perlyna, 93/99, Knyazhna. To the dark color of the leaf plate we attributed the varieties: Stepnaya-90, Ozzie. Among the varieties we studied of the basics of flower color 37% varieties are with a white flower, and 63% with a purple. According to the varieties of standards: Chandor, Cresir, Toreador to the white color of the flower we attributed varieties Knyazhna, Ozzie, Zolotysta. With the purple color of the flower we have selected varieties: 93/99, Zhemchuzhna, Heinong 37. On the basis of the intensity of brown color bean, which characterizes the generative organs of the plant, is divided into weak, moderate and strong, but the other identifiers there are gradations: sandy, gray, light brown, brown and dark brown, so we decided what would be better identify by color gradation. To the sandy color of the beans we attributed varieties Perlyna, Yuh-30; gray – Sribna Ruta; light brown – Kobza, Knyazhna; brown – Ksenya; dark brown – Zhemchuzhna, Vinni. Important features that identify the description of varieties include basic color of the seed coat, which affects the taste of the seeds. In particular, the seeds are divided by color into yellow – Kobza, Yuh-30; yellow-green – Vinni, Luch Nadezhdy; green – Heorhina; light brown – 2947 564/84, brown – DSS 2504; dark brown – 2974 YS-24 and black color – not detected. Following the results of the previous collection of soybean varieties from the morphological sings of vegetative, generative organs of plants, it was possible to identify varieties with stable manifestation of standard identifying sings of soybean. Collection varieties with one standard characteristics: Heinong 37, Luch Nadezhdy, DSS 2504, 2974 YS-24; two signs: Zolotysta, Diona, Stepnaya-90, Zuma, Ksenya, Heorhina, Sribna Ruta, Perlyna, 93/99, Zhemchuzhna; three signs: Ozzie, 2947 564/84, Yuh-30, Vinni, Knyazhna.

Treatment of spent wash effluent using Kaolin immobilised nano ZnO photocatalyst and material characterisation

ABSTRACTThe distillery effluent causes a crucial ecological impact when disposed untreated into the environment and the removal of the intense brown colour is a much challenging task due to the presence of a polymeric compound – Melanoidin. This research study reports the synthesis and application of a nano ZnO photocatalyst in an immobilised form. The process parameters such as photocatalyst dosage (0.5–2.5 g/L), initial pH (3–11), initial spent wash concentration and treatment time were optimised to attain the maximum spent wash degradation efficiency. The physical and chemical properties of the as-synthesised photocatalyst were characterised by X-ray diffractometer (XRD), high-resolution scanning electron microscopy (HRSEM), energy dispersive analysis X-ray (EDAX), Brunauer–Emmett–Teller (BET) surface area analysis, diffuse reflectance spectroscopy (DRS) and Fourier transform infrared (FTIR) spectroscopy. The percentage colour degradation of spent wash increased from 36.2 to 77.1%, with increasing photocatalyst dosage from 0.5 to 2.5 g/L, respectively. The reaction rate constant (kobs) decreased from 0.0141 to 0.0022 (1/min) with increasing initial spent wash concentration (% dilution) of 5–25%. The photocatalytic degradation experiment performed at optimised process parameters yielded a maximum of 91.2% of spent wash colour degradation.

Synthesis of FexZn1-xCr2O4 brown ceramic pigment by starch-assisted sol-gel process

In the present paper, the ceramic pigments FexZn1-xCr2O4 (x = 0 ¸ 1) were synthesized with the starch-assisted sol-gel method. The resulting pigments were characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM), and CIE L*a*b* color measurement. The results show that FexZn1-xCr2O4 pigments form at sintering temperature of 1100 OC for 60 minutes. The ACr2O4 spinel (A: Zn, Fe) and FeCrO3 perovskite phase with excellent crystallinity appears. The brown color intensity increases gradually with the increase of the number of substituted Fe2+ cations. The pigments meet industrial requirements in terms of physicochemical characteristics.

ANALISIS SIFAT FISIK BIJI KAKAO PADA BERBAGAI METODE FERMENTASI DAN KONSENTRASI FERMIPAN

This research was done to analyze physical properties of fermented cocoa beans using various fermentation methods and fermipan concentrations. The aim of this study was to identify effective fermentation methods to produce quality cocoa beans. For each trial 10 kg of fresh cocoa beans were treated with fermipan in concentrations 0.5% w/v and 1% w/v. Fermentation trials were conducted in wooden boxes, plastic baskets and in heaps without turning the materials. The trials were conducted aerobically at room temperature for the next 6 days (144 hours). The results showed that the cocoa bean temperature increased significantly the 24th hour of fermentation and then slowly decreased until the end of the fermentation period except for the beans in heaps. The highest temperature of 42oC was found in beans in wooden boxes using the 1% w/v fermipan concentration. During fermentation, the pH of the pulp increased according to the period of fermentation and reached a peak at 144 hour. The highest pH was 7.02 found in beans placed in plastic baskets with 1% w/v of fermipan concentration. Overall the cocoa beans which fermented in wooden boxes with 1% w/v of fermipan gave the best quality with shell content of 15.05 %, brown color intensity of 90%, unfermented beans 2%, insect infestation 1.14% and beans germinated 1.90%.

Facile Synthesis of Silver Nanoparticles of Aqueous Extract of Bhut Jolokia a Cultivar of Capsicum chinense Jaqc and its Antibacterial Effect

The article explores a novel method of synthesizing silver nanoparticle using aqueous extract of Capsicum chinense Jaqc. The capsaicinoid alkaloids and polyphenols served as an reducing and stabilizing agent in the formation silver nanoparticles. The formation of silver nanoparticle was confirmed by the surface Plasmon resonance which occurred at 430 nm. A gradual colour change of the reaction medium occurred from colourless to pale yellow tinge followed by pale red and then to intense reddish brown colour. The completion of nanoparticle synthesis occurred at 6 hr, as further increased in reaction time showed a marginal rise in the intensity of colour. The characterization of the formed silver nanoparticle was carried out using UV Visible Spectrophotometry and Transmission Electron microscopy. The antibacterial studies were carried out using well diffusion technique using pure culture of Escherichia coli, which showed an inhibition zone of 11.8 mm at a dosage of 70 μg/ml.

Evidence for pyrazine-based chromophores in cloud water mimics containing methylglyoxal and ammonium sulfate

Abstract. Simulating aqueous brown carbon (aqBrC) formation from small molecule amines and aldehydes in cloud water mimics provides insight into potential humic-like substance (HULIS) contributors and their effect on local and global aerosol radiative forcing. Previous work has shown that these (Maillard type) reactions generate products that are chemically, physically, and optically similar to atmospheric HULIS in many significant ways, including in their complexity. Despite numerous characterization studies, attribution of the intense brown color of many aqBrC systems to specific compounds remains incomplete. In this work, we present evidence of novel pyrazine-based chromophores (PBCs) in the product mixture of aqueous solutions containing methylglyoxal and ammonium sulfate. PBCs observed here include 2,5-dimethyl pyrazine (DMP) and products of methylglyoxal addition to the pyrazine ring. This finding is significant as the literature of Maillard reactions in food chemistry tightly links the formation of pyrazine (and related compounds) to browning in foods. We investigated the roles of both cloud processing (by bulk evaporation) and pH in absorptivity and product distribution in microliter samples to understand the contribution of these PBCs to aqBrC properties. In agreement with previous work, we observed elevated absorptivity across the entire UV–visible spectrum following simulated cloud processing as well as higher absorptivity in more basic samples. Absorptivity of the pH 2 sample, following evaporation over a period of days, exceeded that of the unevaporated pH 9 sample. In addition, mixtures of ammonium sulfate and methylglyoxal at pH 5 that were dried in under 1 h and analyzed 24 h later were as absorptive as pH 9 samples allowed to react for 7 days, indicating that evaporation occurring during cloud processing may provide a reaction pathway favorable for carbonyl–ammonia chemistry even under acidic conditions of aerosol and cloud water. The fraction of pyrazine compounds in the product mixture increased by up to a factor of 4 in response to drying with a maximum observed contribution of 16 % at pH 5. Therefore, cloud processing under acidic conditions may produce PBCs at the expense of imine- and imidazole-derived compounds. This finding has implications for further BrC reactivity and degradation pathways.

Comparative Effect of Dietary Soybean Oil, Fish Oil, and Coconut Oil on Performance, Egg Quality and Some Blood Parameters in Laying Hens

Two hundred and sixteen 28-wk-old Hy-line laying hens were randomly distributed to three dietary treatments and fed 1of 3 diets containing 8% soybean oil, fish oil, or coconut oil from 28 to 47 wk of age to investigate comparative effect of dietary soybean oil, fish oil, and coconut oil on the performance, egg quality and blood malondialdehyde (MDA), aspartate transaminase (AST) and uric acid (UA). Hens fed fish oil showed poor performance compared with soybean oil or coconut oil, and especially egg weight throughout the trial was significantly and consistently decreased (P < 0.05) due to dietary fish oil. Unexpectedly, shell reflectivity throughout the majority of the trial was consistently and significantly higher (P < 0.05) when hens fed fish oil than that when fed soybean oil or coconut oil. Dietary treatments affected (P < 0.05) shell shape at 4 of 8 time points tested. Average shell shape in fish oil treatment was higher (P < 0.05) than that of coconut oil group. Albumen height, Haugh unit and yolk color were influenced by dietary treatments only at 1 or 2 time points. However, average albumen height and Haugh unit in fish oil treatment were higher (P < 0.05) than that of soybean oil or coconut oil treatments and average yolk color in coconut oil treatment was higher (P < 0.05) than that of soybean oil group. Serum MDA, AST and UA concentrations were increased (P < 0.05) by fish oil during the majority of the first 2 mo of the trial. These data suggested that the inclusion of fish oil into feed may reduce the performance of laying hens, especially the egg weight, decrease the intensity of egg brown color and increase blood MDA, AST and UA levels compared with soybean oil or coconut oil. As a result, hens fed fish oil may lay smaller, longer and lighter-brown eggs whereas those fed coconut oil produce blunter and darker-brown eggs relative to soybean oil.

English

The present work was conducted to evaluate a simple effective technique for spectrophotometric determination of two flavonoids namely diosmin (1) and rutin (2) in the isolated fractions obtained from Persicaria salicifolia, authentic and pharmaceutical dosage forms, the method is based on the reduction of Ag+ cations to silver nanoparticles (Ag-NPs) by the effect of these flavonoids in the presence of polyvinylpyrrolidone (PVP) as a stabilizing agent which result in production of intense brown colour corresponding to the formation of the surface plasmon resonance of produced silver nanoparticles. The plasmon absorbance of the Ag-NPs allows quantitative spectrophotometric determination of these flavonoids where calibration curves derived from the changes in absorbance at λ=415 and 432 nm were linear with concentration range of diosmin and rutin 1-8 and 0.5-7.0 µg/mL while their detection limits (3σ) were 0.26 and 0.12, respectively. The method was applied successfully for the determination of flavonoids in extract, authentic and pharmaceutical dosage forms. The haemostatic activity of the total methanol extract, isolated fractions, authentic and dosage forms were investigated for their usual and silver nanoparticulated forms using tail bleeding time and amount of bleeding assays in rats, where the nanoparticulated samples exhibited more significant activities. Key words: Persicaria, diosmin, rutin, silver nanoparticles, spectrophotometry, haemostatic.