• Agricultural and Biosystems Engineering
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• v.1 no.1
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• pp.16-21
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• 2000

Measurement of spray deposit is necessary for evaluation of a chemical application technology. However it is not easy and time consuming. A simple method for measuring the deposition amount of spray using a tracer and a spectrophotometer was developed. Various materials were tested to determine an adequate tracer. Food dye was selected as a tracer, because it was cheep and easily treatable. Using NIRS(Near Infrared Reflection Spectrophotometer), a regression curves between maximum absorbance of a solution and concentration of the tracer were obtained. Yellow food dye solution showed a peak of spectrum at 452 nm, and absorbance of peak showed a tendency to increase as concentration increased. Green or pink food dye were tested and judged to be good tracers. However, tracer concentration should not exceed certain limits in order to measure maximum absorption. Using spraying liquid with known tracer concentration and known amount of washing liquid, spray deposit amount on real targets on leaves could be estimated at less than 13% error level.

• Journal of Food Hygiene and Safety
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• v.2 no.1
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• pp.9-14
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• 1987

With the market of food products, the use of food additives is on the increase. The dye as food additives, can be used for some foods which are difficult to preserve their own colors. It can be also classified as tar dye, vegetable dye and mineral dye. Because tar dye has dense toxicity, only 15 articles among them are legally allowed to be used. Among the allowed articles, the azo compound amaranth, tartrazine, sunset yellow, and allura red, were used in determining and comparing rat hepatic azo reductase activity and we observed the flavin's effects as follows: 1. Investigation with amaranth as substrate gave an apparent Km of $645\;\mu\textrm{M}$ and Vmax of 50 n mol/min/mg protein. 2. On investigation using a fixed amaranth concentration over a range of flavin concentration, FAD significantly increased the activity of the azo reductase compared with only minor increases in reaction mediated by the NADPH-generating system alone. 3. On investigation with amaranth, tartrazine, sunset yellow allura red as electron acceptor in the absence or presence of 300 mM-FAD, sunset yellow was reduced at a rat similar to amaranth, tartrazine was reduced at a slower rate and allura red was reduced a little more rapidly.

• Korean Journal of Food Science and Technology
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• v.43 no.6
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• pp.754-759
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• 2011

Zinc protoporphyrin (ZnPP) is produced endogenously during heme metabolism and treated in cells as a heme oxygenase inhibitor. In the present study, the effects of ZnPP on the color response of 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, a commonly-used method for analyzing cell viability, were investigated. ZnPP induced rapid decolorizaion of MTT formazan under light; the degradation rates were 10- and 20- folds faster in the presence of 5 and $10{\mu}M$ ZnPP, respectively. Methylene blue (MB), another type of photosensitizer, also accelerated degradation of formazan under light. Butylated hyroxytoluene did not inhibit ZnPP- or MB-induced formazan degradation. The color degradation of formazan dye was signficantly delayed in the presence of N-acetylcysteine or ${\beta}$-carotene. The present results suggest that certain photosensitizing compounds may affect the color and stability of MTT formazan, which should be carefully considered when conducting the MTT assay.

• Journal of environmental and Sanitary engineering
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• v.22 no.2
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• pp.75-84
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• 2007

A lysine determination method for low quantity of rice was modified from the original Dye-Binding Lysine (DBL) method used in the national standard in China [GB 4801-84, 1984]. By making use of the property that lysine does not bind to the crocein orange G dye after treated with propionic anhydride, the amount of lysine in rice samples could be determined directly by calculating the difference between the absorbances of the treated and the untreated samples. Various commercial rice samples were purchased from market and evaluated. Several methods were tested by varying both the sizes of the samples and the concentrations of the dye solutions. Results showed that when using 1.284 mM of crocein orange G dye solution and 15.5 mg of sample, the results were most reproducible. The corresponding lysine content in sample were $3.36\;{\pm}\;0.09\;mg/g$ and $3.35\;{\pm}\;0.19\;mg/g$ by traditional method and modified method, respectively. Statistically, there was no significant difference between the results (p>0.05).

• Biotechnology and Bioprocess Engineering:BBE
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• v.11 no.1
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• pp.84-87
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• 2006

Batch binding experiments were performed to assess the recovery performance of glyceraldehyde 3-phosphate dehydrogenase (G3PDH) bound to the unshielded and polymer (polyvinyl pyrrolidone. PVP)-shielded dye-ligand (Cibacron Blue 3GA) adsorbent. The adoption of a polymer-shielded, dye-ligand technique facilitated the elution efficiency of bound G3PDH. It was demonstrated that the recovery of G3PDH using polymer-shielded dye-ligand adsorption yielded higher elution efficiency, at 60.5% and a specific activity of 42.3 IU/mg, after a low ionic strength elution (0.15 M NaCl). The unshielded dye-ligand yielded lower elution efficiency. at 6.5% and a specific activity of 10.2 IU/mg.

• Korean Journal of Food Science and Technology
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• v.3 no.2
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• pp.101-104
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• 1971

The dye-binding method based on the reaction of acidic orange-G dye with basic groups of protein molecule was investigated to observe its applicability to the determination of protein, basic amino acid and lysine contents in brown rice of several high-protein rice lines. The protein content of rice samples ranged from 7.91 to 10.53% and from 8.93 to 11.96% in terms of wet and dry bases, respectively. The correlation between dye-binding absorbance and protein content in terms of both dry and wet bases was highly significant; their correlation coefficients being $-0.955^{**}\;and\;-0.975^{**}$, respectively. The correlation of dye-binding absorbance lysine and basic amino acids were highly significant and their correlation coefficients were similar. Dye-binding absorbance-lysine showed a lower correlation than dye-binding absorbance-protein but a higher correlation than protein-lysine.

• Preventive Nutrition and Food Science
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• v.14 no.4
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• pp.358-361
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• 2009

Aldose reductase was purified to electrophoretic homogeneity from porcine liver. The purified enzyme was a monomer of 36 kDa. The enzyme was strongly inhibited by $Cu^{2+}\;and\;Mg^{2+}$ ions. Incubation of the enzyme with pyridoxal 5'-phosphate led to complete inhibition of enzymatic activity, suggesting that lysine residue is involved at or near the active site of the enzyme. The enzyme exhibited a broad substrate specificity. Furthermore, the enzyme was capable of decolorizing Alizarin, an anthraquinone dye.

• Textile Coloration and Finishing
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• v.24 no.4
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• pp.253-259
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• 2012

In this work, the natural indigo production process from Polygonum tinctorium was balanced based on the traditional Niram method in Korea. A standard procedure was determined considering the conditions of indican extraction from plant material, the amount of alkali for precipitation, storage of extract, etc. The effect of experimental conditions on the yield of crude dye was investigated. The contents of indigo and indirubin of the crude dyes were analyzed by HPLC. Increase of the amount of crude dye was observed within 1-2.5 days of extraction time. Longer extraction beyond 2.5 days resulted in a slight decrease in the amount of crude dye. There was no consistency in terms of indigo content depending on extraction pH. We found that the storage of extract or harvested plants affected adversely to dye yield and dye quality. Based on the lab scale extraction, large scale extraction was performed for 2-2.5 days in water and 2.0-2.5 g/L of $Ca(OH)_2$ was applied for precipitation of indigo dye. We obtained natural indigo dye containing about 15% of pure indigo in scale-up production using whole plant except root.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.24 no.3
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• pp.167-180
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• 2018

Interest in the use of smart packaging systems for food products has increased in recent years. Therefore, food researchers are focusing on the development of new indicator based smart packaging technologies by using anthocyanin-based natural dye. Anthocyanins are one of the plant constituents known as flavonoids and responsible for the bright and attractive orange, red, purple, and blue colors of most fruits, vegetables, flowers, and some cereal grains. Indicators of natural dyes such as anthocyanins could express the quality and shelf life of perishable food products. However, the sensitivity and stability for their use in smart food packaging should be established to reach the market proposals. This review article focuses on recent studies related to use of natural dyes based on anthocyanin for smart food packaging applications. This study offers valuable insight that may be useful for identifying trends in the commercialization of natural dyes or for identifying new research areas. This review also provides food and packaging scientists with a thorough understanding of the benefits of anthocyanin-based natural dyes for shelf life indicator when applied to package material specific foods and hence can assist in accelerating commercial adoption.

• Biotechnology and Bioprocess Engineering:BBE
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• v.10 no.6
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• pp.552-555
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• 2005

The influence of whole yeast cells $(0{\sim}15%\;w/v)$ on the protein adsorption performance in dye-ligand chromatography was explored. The adsorption of a model protein, bovine serum albumin (BSA), was selected to demonstrate this approach. The UpFront adsorbent $(p=1.5\;g/cm^3)$ derivatised with Cibacron Blue 3GA and a commercially available expanded bed column (20 mm i.d.) from UpFront Chromatography, Denmark, were employed in the batch binding and expanded bed operation. The BSA binding capacity was demonstrated to not be adversely affected by the presence of yeast cells. The dynamic binding capacity of BSA at a $C/C_0=0.1$ biomass concentration of 5, 10, 15% w/v were 9, 8, and 7.5mg/mL of settled adsorbent, respectively.