Degree Of Decolorization Research Articles

Decolorization of molasses and a dye by a newly isolated strain of the fungus Geotrichum candidum Dec 1.

A fungus, Geotrichum candidum Dec 1, newly isolated as a dye-decolorizing microorganism, was used to decolorize molasses and an anthraquinone dye in shaken flasks. A degree of decolorization of molasses of 87% was achieved after 12 days of cultivation, and the maximum rate of decolorization of the dye in the culture broth was obtained in 7 days. The apparent activity of peroxidase in the molasses, which is responsible for dye decolorization, was significantly lower than that of purified peroxidase, due to the inhibition by molasses, but the inhibition was reduced after the fungus was fully grown. As two ultrafiltered fractions of molasses were similarly decolorized by Dec 1, Dec 1 apparently degraded colored substances of a wide range of molecular weights. When Dec 1 was cultivated in a medium in which sucrose in the molasses was hydrolyzed with invertase, the degree of decolorization of molasses, and rate of decolorization of the dye were similar to these obtained above.

Oxidation of Crocein Orange G by lignin peroxidase isoenzymes. Kinetics and effect of H2O2.

The ligninolytic enzyme system of Phanerochaete chrysosporium is able to decolorize several recalcitrant dyes. Three lignin peroxidase isoenzymes, LiP 3.85, LiP 4.15, and LiP 4.65, were purified by preparative isoelectric focusing from the carbon-limited culture medium of P. chrysosporium. Based on amino terminal sequences, the purified isoenzymes correspond to the isoenzymes H8, H6, and H2, respectively, from the N-limited culture. The purified isoenzymes were used for decolorization of an azo dye, Crocein Orange G (COG). According to the kinetic data obtained, the oxidation of COG by lignin peroxidase appeared to follow Michaelis-Menten kinetics. Kinetic parameters for each isoenzyme were determined. The inactivating effect of ascending H2O2 concentrations on COG oxidation is shown to be exponential within the used concentration range. The best degree of decolorization of 100 microM COG was obtained when the H2O2 concentration was 150 microM. This was also the lowest H2O2 concentration for maximal decolorization of 100 microM COG, regardless of the amount of lignin peroxidase used in the reaction.

Decolorization of molasses by a new isolate of Geotrichum candidum in a jar fermenter

Decolorization of crude molasses by a newly isolated dye-decolorizing fungus, Geotrichum candidum Dec 1, was conducted in a jar fermentor system having fan-type propellers and a pressure swing adsorption oxygen generator. The oxygen-fortified air supply was effective not only to obtain a highest decolorization degree of 80% molasses but also the highest peroxidase activity which is responsible for the decolorization of the dyes. © Rapid Science Ltd. 1998

Tree bark as a bioindicator of air pollution in Navarra, spain

During a two year research period from 1992 to 1993, samples of different species of trees were taken in 17 forest stands located in Navarra, Spain. From these samples, bark extracts were prepared in which the pH and the conductivity were measured. The health of the sampling trees was also evaluated by determining the degree of defoliation and decoloration of the canopies. The bark tissue analysis revealed the presence of an environmental acidity gradient that decreased from NW to SE. This coincides with the location of important sources of pollution and their course of transport and dispersion. On the other hand, in the samples ofQuercus ilex a significant correlation between the pH and the defoliation levels (P≤0.01, r=0.62) was found. This fact reveals the potential usefulness of tree bark as a health bioindicator of trees.

Disappearance of Anthocyanins as Grape Juice Is Prepared and Oxidized with PPO and PPO Substrates

Red pigments were isolated from Muscat Bailey A and Cabernet Sauvignon grape skins and analyzed by high performance liquid chromatography. Cabernet Sauvignon skin extract contained only anthocyanidin-3-monoglucosides, while that from Muscat Bailey A skins contained about 75% 3-monoglucosides and 25% 3,5-diglucosides. Polyphenoloxidase (PPO) was prepared from Muscat Bailey A juice. Soluble and insoluble PPO fractions were obtained by centrifugation. The PPO fractions had two activities, catecholase (much higher) and cresolase, and showed high activities toward various phenols, especially vicinal diphenols such as caftaric acid, catechol, and caffeic acid. The insoluble fraction had stronger activities than the soluble fraction and was washed free of associated phenols. Enzymatic decolorization and degradation of anthocyanins were studied by measuring the absorbance at 520 nm and by determining the residual anthocyanins by HPLC after the reaction. The enzyme did not oxidize anthocyanins directly (either as flavylium or carbinol forms), but they were decolorized in coupled oxidation of diphenols such as catechol and caftaric acid. The addition of benzenesulfinic acid inhibited decolorization completely and very rapidly, while glutathione partially suppressed the oxidative reaction, showing that quinones produced from oxidizable phenols are the active agents in decolorization of red pigment. The degree of decolorization or degradation of individual anthocyanins was influenced by their structures. The mechanisms involved and the significance of these results are briefly discussed.

Decolorization of Crystal Violet by Fungi and Commercial Horseradish Peroxidase

The decolorization of crystal violet which is a triphenylmethane dye by several fungi was investigated. Coriolus versicolor showed 92%, Funalia trogii 82%, Laetiporus sulphureus 86% and Phanerochaete chrysosporium ME446 62% dye decolorizing ability. Fungi, especially C. versicolor, possess high degree of decolorizing ability. Incubation of the dye with commercial horseradish peroxidase type II resulted in high degree of decolorization. A correlation between the rate of decolorization of the dye by fungi and enzyme was observed.

Studies on the treatment of kraft bleaching effluents with lignin-degrading fungi

Typically, for production of high brightness pulp, the residual lignin in unbleached kraft pulp is commonly removed through a multi-stage bleaching process with the use of chlorine species. The effluent from such a bleaching process is dark brown due to their content of chromophoric and polymeric lignin derivaties. Moreover, the organically bound chlorine [measured as total organically bound chlorine (TOCI) or adsorbable organic halogen (AOX)) is present in a wide range of organic materials which have toxic and mutagenic properties. It has recently been discovered that small quantities of dioxines [polychlorinated dibenzo dioxin (PCDD) and polychlorinated dibenzo furan (PCDF)) can also appear in bleach plant effluents. Consequently, this bleaching effluent is not easily recycled within a mill recovery system because of the potential corrosion problems created by its high chlorine content and finally affects the harmful effects on the environment. The purpose of the present research is to describe the decolorization of the El effluent with white-rot fungi showing the Iigninolytic activity, to accomplish efficient treatment of kraft bleachery efficient with less energy and in relatively short treatment-period. First, it was attempted to design the effective treatment process of the El effluent with the fungus IZU-154 showing ligninolytic activity. It has revealed that the color of the effluent was effectively removed when glucose was added as an additive. Furthermore, the addition of glucono-d-lactone to the El effluent produced a more remarkable degree of decolorization than did that of glucose. All white-rot fungi tested showed high decolorization effect of the El effluent in the presence of glucono-d-lactone. It is suggested that the effect of glucono-d-Iactone on the high decolorization of El effluent are closely associated with the activity of the surfaces of the mycelium due to the change of pH of the effluent during fungal treatment. Moreover, to establish a more practical system for the decolorization of the bleaching effluent, a screening have been performed to find fungi having high decolorization activity of the El effluent without any additional nutrients. The

Roles of Lignin Peroxidase and Manganese Peroxidase from Phanerochaete chrysosporium in the Decolorization of Olive Mill Wastewaters

The relative contributions of lignin peroxidase (LiP) and manganese peroxidase (MnP) to the decolorization of olive mill wastewaters (OMW) by Phanerochaete chrysosporium were investigated. A relatively low level (25%) of OMW decolorization was found with P. chrysosporium which was grown in a medium with a high Mn(II) concentration and in which a high level of MnP (0.65 (mu)M) was produced. In contrast, a high degree of OMW decolorization (more than 70%) was observed with P. chrysosporium which was grown in a medium with a low Mn(II) concentration but which resulted in a high level of LiP activity (0.3 (mu)M). In this culture medium, increasing the Mn(II) concentration resulted in decreased levels of OMW decolorization and LiP activity. Decolorization by reconstituted cultures of P. chrysosporium was found to be more enhanced by the addition of isolated LiP than by the addition of isolated MnP. The highest OMW decolorization levels were obtained at low initial chemical oxygen demands combined with high levels of extracellular LiP. These data, plus the positive effect of veratryl alcohol on OMW decolorization and LiP activity, indicate that culture conditions which yield high levels of LiP activity lead to high levels of OMW decolorization.

Decoloration of vegetable oils and oleoresins with recovery of unaltered pigments

AbstractThe present study confirms that N,N‐dimethylformamide for the extraction of chloroplast pigments from vegetable tissues shows no differences from the usual acetone or methanol. Therefore, it can be applied to fats, as it allows separation of lipids and pigments by means of phase distribution between light petroleum ether and N,N‐dimethylformamide. The ether phase retains the decolored fatty matter, and the pigments dissolved in N,N‐dimethylformamide can be recovered totally unaltered.This method has been applied to oleoresins and oils from different products and origins. Satisfactory results have been obtained in terms of the degree of decoloration and the percentage of oil recovered. At the same time, the unaltered pigment concentrate obtained from the hypophase could be used as a color enhancer in the chemico‐pharmaceutical industry.

An in vitro comparison of bleaching agents on the crowns and roots of discolored teeth

Sixty teeth were stained in vitro to compare the decolorizing effect of three bleaching agents on the crowns and on the roots of teeth containing an intracoronal isolating base. With an intracoronal isolating base placed either at the cementoenamel junction (CEJ) or 2-mm below the CEJ, bleaching agents of Superoxol, sodium perborate, and a combination of the two were placed in the pulp chamber of teeth and the accesses sealed with IRM. Customized shade guides were used to evaluate the color changes of the crowns and roots. After three treatments, the combination technique was found to be more effective in decolorizing the crowns and roots of teeth than Superoxol or sodium perborate alone (p less than 0.05). No difference was found between the Superoxol group and the sodium perborate group. There was no difference in color shades of crowns in which the IRM base was placed either at the CEJ or 2-mm below the CEJ. The roots of all groups showed some degree of decoloration. Based on the bleaching effects on discolored roots, the effectiveness of this seal is questionable.

The radiolysis of bromophenol blue in aqueous solutions

The effect of gamma radiation on the color intensity of aerated and oxygenated aqueous solution of bromophenol blue (BPB) was investigated. Ionizing radiation at increasing absorbed doses ( D) brought about gradual bleaching (i.e. decrease in optical absorbance, -Δ A) of bromophenol blue solutions. The molar extinction coefficients of acidic, neutral, and alkaline solutions were measured and found to be independent of temperature during spectrophotometry between 20 and 40°C. Aerated and oxygen-saturated acidic solutions showed a linear response -Δ A vs D) up to doses of 2.4 and 2.1 kGy, respectively. Aerated alkaline solutions on the other hand showed a linear response up to 4.8 kGy. The decoloration yields for 5 × 10 -5 M bromophenol blue aqueous solutions, G(-BPB), obtained from the decrease in absorbance at 591 nm wavelength for acidic, neutral, and alkaline solutions, were 0.244, 0.113, and 0.098 (100 eV) -1, respectively. The first-order rate constant for the reaction of OH radical with bromophenol, obtained from competition reactions with ethanol at pH 4, was found to be 9.1 +- 1.2 × 10 9 M -1 s -1. The degree of decoloration of bromophenol blue in acidic solutions was found to decrease upon the addition of ethanol, G(-BPB) decreasing from 0.24 to 0.088 upon the addition of ethanol at a concentration of 10 -2M. Suggestions are made for possible radiation dosimetry in the dose range (0.1–5 kGy) by means of spectrophotometric analysis of absorption spectra.

Decoloration and degradation of an anthraquinone dye aqueous solution in flow system using an electron accelerator

A study on the decoloration and degradation of a commercial anthraquinone dye (Acid Blue 40) was carried out by electron-beam irradiation. Experiments were done in a flow system using a five-stage, dual-tube bubbling column reactor. The oxygen contents of the gas bubbled into the inner tubes of the columns were varied from 0 to 100%. The inlet dye concentration, the solution feed rate and the dose rate were also varied from 50 to 100 ppm, 1.5 to 101/min and 0.1 to 0.15 Mrad/s, respectively. The degree of decoloration and degradation of aromatic rings increased with the oxygen content and became close to those for pure oxygen bubbling system at about 25% of oxygen content. The amount of degraded aromatic rings was proportional to that of consumed oxygen. The rate expression of the decoloration and degradation of the dye and the oxygen consumption were derived according to a reaction scheme.

The degradation of an azo dye in aqueous solutions by high-intensity electron-beam irradiation

A study of the degradation of Acid Red 265 (azo dye) in aqueous solutions by high-intensity electron- irradiation was carried out in a flow system. For the oxygen-saturated solutions (oxygen bubbled during irradiation), the change of absorption spectra, the degree of decoloration at 542 nm, the reduction in optical density at 230 nm, the change of pH, and the amount of dissolved oxygen were measured as functions of dose under various conditions (dye concentration, dose rate, solution flow rate, and oxygen flow rate). The decoloration scheme in the flow system by electron beam irradiation was similar to that in the batch system by gamma radiation. Oxygen was not necessary for the destruction of the chromophore but was absolutely essential for the destruction of substituted aromatic rings in the dye molecule. For the purpose of the destruction of the skeleton of the Acid Red 265 molecules, it was necessary to keep the concentration of dissolved oxygen above at about 30 ppm (in mass) in the case of the 60 ppm dye solution.

Rapid and Precise Determination of Small Amounts of SO2 Gas with an Improved Total Conversion Type Color-producing Tube

A simple and accurate method for the rapid and precise determination of the small amounts of SO2 gas with a new type of color-producing tube, which is an improved type of a common gas detector tube and refers to total conversion type of a color-producing (TCC) tube, was tested against the previous results obtained in the determination of NO2 and CO2.The supported color-producing reagent was prepared by spraying uniformly the dilute (0.20 wt%) aqueous solution of rosaniline hydrochloride on 60-80 mesh particles of Merck silica gel60. This reddish pink reagent reacts sensitively with SO2 gas changing into colorless, and the decoloration proceeds instantaneously to completion (1 mol rosaniline hydrochloride consumed 106 mol SO2).The TCC tube, consisting of glass tube, 1-3 mm in diameter and less than 80 mm in length, and being filled with the color-producing reagent, was used for the analysis of SO2. SO2 gas diluted with air (100-400 ml) was made to flow through the tube at a flow rate of below 48 m//min. The decoloration layer extended successively from the inlet of the tube in proportion to the amounts of SO2 supplied, and the degree of decoloration was independent of temperature and SO2 concentration. Excellent linear relationship between the length of decoloration and the total amount of SO2 in the sample was found in any case. Thus, the determination of SO2 (3000-4 ppm) was accurate to within 2% by the suitable use of TCC tube with diameter of 3, 2-1 mm.

The radiation-induced degradation of azo dyes in aqueous solutions

The aqueous solutions of Acid Red 265, Acid Red 37, Reactive Red 8, Reactive Red 3, Direct Red 79 and Direct Blue 78 were easily decolored by gamma radiation. For the oxygen- and nitrogen-saturated solutions, the degree of decoloration, the change of pH, the TOC reduction, the COD reduction and the amount of carbon dioxide formed were measured as functions of dose. After decoloration, the dye molecules are degraded to the lower molecular weight compounds, mainly, such as organic acids, and finally to carbon dioxide. The degradation reaction is promoted markedly by oxygen.

Toxicologic studies of petrolatum in mice and rats

The present studies were undertaken as a basis for determining the status of food grade petrolatum as a food additive under the terms of the Food Additives Amendment of 1958. The investigations of the petrolatum included 2-year rat feeding studies and single subcutaneous injections in mice followed by observation over an 18-month period. Previous work and the considerations leading to regulatory interest in the potential carcinogenicity of paraffin hydrocarbons have been reviewed in the extensive report on the toxicity of petroleum waxes by Shubik et al. (1962). Three specific color grades of petrolatum which met either USP XVI or NF XI (White or Yellow Petrolatum) were selected to represent the range of degrees of decolorization of petrolatum commonly used as direct food additives, or which may be incorporated in foods as an indirect additive, incidental to its use in processing.

ビン長およびキハダ鮪青肉に関する研究-II

As a link in the present studies on the green meat of albacore and yellowfin tuna, a discovery was attained of that the strength in which meat specimens can react in hot water on a redox indicator pigment thereto added makes a reliable standard for the grade judgment of meats according to their inclinations to becoming green meat, while said strength was found to have any positive connection neither with reflectance spectra nor with redox potential of the corresponding raw meat. Among several pigments or redox indicators thus far tested, Lauth's violet was found as most suitable to be used in said reaction in hot water. Although a higher pH in reaction medium allows the reaction to take place with the more strong impression, application of a pH greater than 6.00 should be avoided because of its often causing the decolorization degree of pigment to go out of the regularity observed in a lower range of pH of its prevalence among meat specimens of different grades, thus reducing the accuracy of judgment. It was thus found desirable that pH value of the reaction system is kept at about 5.90, for example, by the use of an aqueous acetate buffer of pH 5.65. Details in practical application of the redox indicator decolorizing reaction to predicting the latent tendency to green meat development were inquired according to the following procedure, using frozen meats of albacore and yellowfin tuna as sample: Every 5g. of ground samples was brought in a test tube into a state of suspension in 20ml. of a 0.2M acetate buffer solution of pH 5.65, which contained Lauth's violet at a concentration of 2 mg%. The test tubes were then heated after loosely plugging with glass stoppers in a boiling water bath, still kept in the bath after the completion of coagulation of the meat with occasional stirring up the coagulum for additional 30-45min. and then taken out of the bath for the degrees of decolorization of redox indicator to be observed for different grades of meat. Through arranging the degrees of decolorization thus observed in accordance with the strengths of actually observed green meat development, a conclusion was drawn that meat of such a weak reactivity as unable to strongly decolorize Lauth's violet and left colored blue or bluish green (such negative decolorization is expressed in Fig. 5 as marked with-) should be classified either into a meat destined to become “green meat” or at least into a meat of low grade. The correlation between the grade of cooked meat and the redox indicator decolorizing power which the same meat develops on heating was confirmed of its prevalence upon the experimental results obtained with 97 and 64 individuals of albacore and yellowfin tuna, respectively. As a measure for predicting the green meat development, reliability of said decolorizing power may be considered as compatible with that of the chromatographical, yellow spot developing property8) of meat specimens already reported from our laboratory, though these two kinds of phenomenon stand in mutual exclusion. It was confirmed that the more strongly inclined the raw meat to green meat development, the weaker is its power of decolorizing a redox indicator, while the entity of the meat constituent that weakens the decolorizing power has not been chemically identified as yet.

Anesthesia. XLIII. The Estimation of Anesthetic Trifluoroethyl Vinyl Ether in Aqueous Solution*

The instantaneous reaction between trifluoroethyl vinyl ether and bromine water, resulting in a decolorization of the latter, has been adated for the colorimetric estimation of this ether in aqueous solution. Under suitaile conditions the degree of decolorization is roportional to the amount of the ether used. The method is simple and rapid and may be applicable to the examination of numerous other substances which are highly reactive toward bromine water in a similar manner.

A Critical Study of the Chromosomes of <i>Lymantria dispar</i> L. in Relation to the Question of Racial Difference

In the cytological studies of the geographic races of Lymantria dispar, GOLDSCHMIDT ('17, '20, '32) pointed out racial size difference of chromosomes indicating that the amount of chromatin is in an inverse proportion to the strength of sex-races. Close examination of his data revealed some questionable points worthy of study. The reinvestigation was here undertaken by the authors with material coming from twelve localities. The races coming under study are treated as follows: the weak race from Sapporo, the neutral race from Kyoto, Ayabe and Kumamoto, and finally the strong race from Aomori, Tokyo, Matumoto, Misima, Nagoya, Gifu, ogaki and Maibara.The haploid number, 31, was obtained in the study of the primary and secondary spermatocyte throughout the geographic races under observation. The diploid number, 62, was observed in the spermatogonial metaphase of one of the races. The chromosomes of the haploid group are round or oval in outline and vary in size very slightly forming a well graded series in the diminution of size. It was found to be practically impossible to group the chromosomes as large, medium and small ones, as done by GOLDSCHMIDT.The comparative study of chromosomes of the geographic races leads to the conclusion that the chromosomes of the studied races are fairly identical in their general appearance, especially in regard to the size of chromosomes, and that there is detected no essential morphological difference in the chromosomes among the races obtained from the different localities and also among the different sex-races.In the light of these studies it must be concluded that GOLDSCHMIDT'S contention that the chromosomes of the weak, neutral, and strong sex-races of Lymantria dispar show perceptible size differences resulted from mistaken observation and irregular technique. The error apparently resulted from: (1) a confusion between the secondary and. primary spermatocytes; and (2) varying degrees of decolorization in the staining process, producing the variation of chromosome sizes.

Detection of Clay Minerals in Soil Mortars by Photo-electric Cell

A RECENT communication by V. L. Bosazza1 lends point to a description of the application of the photoelectric cell to the determination of the nature of the clay minerals present in soil mortars. After treatment with a solution of malachite green for a period of 10–15 min. to permit of base exchange, the liquid is filtered into a glass cell. The degree of decolorization of the filtrate is a measure of the amount of base exchange between clay minerals and stain, and this can be evaluated quantitatively by placing the filtrate between a light source and a photo-electric cell having a sensitive galvanometer in circuit. Clay fractions which are dominantly quartzose in type remove little of the stain, while those of the kaolinite or beidellite types produce an almost clear filtrate. Colour differences in the filtrates obtained from different clay fractions can then be measured by means of the galvanometer.