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     

Decolorization of dye and molasses by continuous and semi-continuous jar-fermentor cultures ofGeotrichum candidum Dec 1

Two culture modes, continuous and semi-continuous, of the decolorization fungus,Geotrichum candidum Dec 1, were compared to obtain a high treatment efficiency of molasses decolorization and a large productivity of peroxidase (DyP) to simultaneously decolorize dyes and molasses. The continuous culture ofG. candidum Dec 1 using a 5-l jar-fermentor showed high DyP activity at a low dilution ratio of 0.005h⁻¹, and decolorization ratio of molasses of 80% was obtained concomitantly. Therefore, a semi-continuous culture was performed by repeated refill and draw. In this mode, approximately 1.5 liters of the culture broth was replaced per cycle when the decolorization ratio of molasses was near 80%. The molasses medium (1.0 liter per day) was treated and the peroxidase productivity in the drawn culture broth was 26.6 U/day, whereas the peroxidase productivity was 17.9 U/day in the continuous culture with a dilution rate of 0.005 h⁻¹. The semi-continuous treatment system was an efficient decolorization method for the strain,G. candidum Dec 1.     

藜芦醇和吐温80对白腐菌产木质素降解酶的影响及在偶氮染料脱色中的作用

担子菌PM2在限氮液体培养下,分泌木质素过氧化物酶和锰过氧化物酶;藜芦醇、吐温 80的补充,提高了该菌锰过氧化物酶的产生,获得的最大锰过氧化物酶Mnp酶活为254.2u/L、190.2 u/L,分别是对照的3.4倍和2.5倍。选择三种偶氮染料,在染料体系下,进一步分析藜芦醇、吐温 80对担子菌PM2产过氧化物酶及染料脱色的影响。结果表明,担子菌PM2分泌的锰过氧化物酶Mnp与染料脱色有关,脱色程度受其分子结构特征影响;吐温80的补充,更有利于染料的脱色降解,48h后三种染料均可达到80%以上的脱色率。     

Production of some extracellular enzymes by a lignin peroxidase-producing brown rot fungus, Polyporus ostreiformis, and its comparative abilities for lignin degradation and dye decolorization.

Polyporus ostreiformis produced Mn peroxidase, acid protease, alpha-amylase, and lignin peroxidase, with maximum activities of 40, 8,300, and 4,200 U liter-1 and 50 nkat liter-1, respectively, in nitrogen-limited liquid media. The fungus removed only 18.6% lignin from rice straw in 3 weeks but effected 99% decolorization of Congo red dye in 9 days.     

Bioremediation of Textile Azo Dyes by Trichophyton rubrum LSK-27

Summary The potential of a recently isolated wood-degrading fungus, Trichophyton rubrum LSK-27, for effective decolorization of textile azo dyes was evaluated. Within two days of dye addition, the fungus was able to decolorize 83% of Remazol Tiefschwarz, 86% of Remazol Blue RR and 80% of Supranol Turquoise GGL in liquid cultures. The reactive dyes, Remazol Tiefschwarz and Remazol Blue, were removed by fungal biodegradation, while decolorization of the acid dye, Supranol Turquoise GGL, was accomplished mainly by bioadsorption. Therefore the fungus proved to be efficiently capable of both biodegradation and biosorption as the major dye removal mechanisms. The extent of biodegradation was associated with the levels of the extracellular ligninolytic enzymes such as manganese peroxidase and laccase.     

白囊耙齿菌对茜素红脱色条件优化及其毒性变化检测

白囊耙齿菌Irpex lacteus是分离自倒木上的一株可以分泌漆酶和锰过氧化物酶的白腐真菌。利用I. lacteus对固体条件下的活性黑、活性红、结晶紫、茜素红和孔雀石绿进行脱色能力的检测,通过单因素和正交试验优化I. lacteus对茜素红的脱色条件,并以3种作物发芽率为指标测定茜素红被I. lacteus脱色前后的毒性变化。结果显示,I. lacteus对5种染料均可脱色,其中对茜素红染料的脱色更为彻底;单因素和正交试验优化I. lacteus对茜素红的脱色条件为：pH 7.0、葡萄糖10.0g/L、硫酸铵0.66g/L、接种量2片（Φ=8.0mm）、100.0mL三角瓶装液20.0mL,优化条件下I. lacteus对茜素红脱色10d时的脱色率为88.26%,与未优化前的脱色率相比提高了60.50%;茜素红染料被I. lacteus脱色前后毒性大小排序为：染料原液>染料脱色后>PDB培养基处理,表明茜素红染料存在一定的毒性,I. lacteus脱色茜素红后可以使其毒性减弱。通过本研究,为I. lacteus在茜素红等染料废水脱色以及降低染料废水毒性方面的应用奠定基础。     

The role of enzymes produced by white-rot fungus Irpex lacteus in the decolorization of the textile industry effluent

The textile industry wastewater has been decolorized efficiently by the white rot fungus, Irpex lacteus, without adding any chemicals. The degree of the decolorization of the dye effluent by shaking or stationary cultures is 59 and 93%, respectively, on the 8th day. The higher level of manganese-dependent peroxidase (MnP) and non-specific peroxidase (NsP) was detected in stationary cultures than in the cultures shaken. Laccase activities were equivalent in both cultures and its level was not affected significantly by the culture duration. Neither lignin peroxidase (LiP) nor Remazol Brilliant Blue R oxidase (RBBR ox) was detected in both cultures. The absorbance of the dye effluent was significantly decreased by the stationary culture filtrate of 7 days in the absence of Mn (II) and veratryl alcohol. In the stationary culture filtrate, three or more additional peroxidase bands were detected by the zymogram analysis.     

Decolorization of azo, triphenylmethane and anthraquinone dyes by a newly isolated Trametes sp. SQ01 and its laccase

A white-rot fungus, strain SQ01, was isolated from decayed wood in a temperate forest. The strain was identified as a member of genus Trametes, based on the morphological characteristics and a complete sequence analysis of its 18S rRNA gene and ITS region. Strain SQ01 was capable of decolorizing a variety of synthetic dyes, including azo, triphenylmethane, and anthraquinone dyes, with an optimal efficiency of decolorization obtained when dyes added after 5 days of culture, with the exception of Cresol Red, showing that the point of dye addition was an important influencing factor for decolorization by this fungus. All of the tested dyes were decolorized by the purified laccase in the absence of any redox mediators, but only a few were completely removed, while others were not completely degraded even with increased decolorization time.     

Enhanced production of ligninolytic enzymes and decolorization of molasses distillery wastewater by fungi under solid state fermentation

Selected isolates of fungi were grown on wheat straw and corncob in the presence of different moistening agents such as water, molasses, potato dextrose broth and distillery effluent. All the fungal isolates responded differently with respect to growth and ligninolytic enzyme production. Fungal growth on different substrates was checked by calculating ergosterol content, which varied widely within a single species when grown on different substrates. The maximum laccase production was obtained for Aspergillus flavus TERI DB9 grown on wheat straw with molasses. For manganese peroxidase, highest production was in Aspergillus niger TERI DB20 grown on corncob with effluent. Among the two isolates positive for lignin peroxidase, the highest production was in Fusarium verticillioides ITCC 6140. This immobilized fungal biomass was then used for decolorization of effluent from a cane molasses based distillery. Maximum decolorization (86.33%) was achieved in Pleurotus ostreatus (Florida) Eger EM 1303 immobilized on corncob with molasses in a period of 28 days.     

Decolorization and detoxication of reactive industrial dyes by immobilized fungi <Emphasis Type="Italic">Trametes pubescens</Emphasis> and <Emphasis Type="Italic">Pleurotus ostreatus</Emphasis>

Trametes pubescens and Pleurotus ostreatus, immobilized on polyurethane foam cubes in bioreactors, were used to decolorize three industrial and model dyes at concentrations of 200, 1000 and 2000 ppm. Five sequential cycles were run for each dye and fungus. The activity of laccase, Mn-dependent and independent peroxidases, lignin peroxidase, and aryl-alcohol oxidase were daily monitored during the cycles and the toxicity of media containing 1000 and 2000 ppm of each dye was assessed by the Lemna minor (duckweed) ecotoxicity test. Both fungi were able to efficiently decolorize all dyes even at the highest concentration, and the duckweed test showed a significant reduction (p 相似文献   

Purification and characterization of a novel peroxidase from Geotrichum candidum dec 1 involved in decolorization of dyes

A peroxidase (DyP) involved in the decolorization of dyes and produced by the fungus strain Geotrichum candidum Dec 1 was purified. DyP, a glycoprotein, is glycosylated with N-acetylglucosamine and mannose (17%) and has a molecular mass of 60 kDa and an isoelectric point (pI) of 3.8. The absorption spectrum of DyP exhibited a Soret band at 406 nm corresponding to a hemoprotein, and its Na2S2O4-reduced form revealed a peak at 556 nm that indicates the presence of a protoheme as its prosthetic group. Nine of the 21 types of dyes that were decolorized by Dec 1 cells were decolorized by DyP; in particular, anthraquinone dyes were highly decolorized. DyP also oxidized 2,6-dimethoxyphenol and guaiacol but not veratryl alcohol. The optimal temperature for DyP activity was 30 degrees C, and DyP activity was stable even after incubation at 50 degrees C for 11 h.     

Biodegradation of Green HE4B: Co-substrate effect,biotransformation enzymes and metabolite toxicity analysis

A high exhaust reactive dye, Green HE4B (GHE4B) was 98% degraded in nutrient medium by Pseudomonas desmolyticum NCIM 2112 (pd2112) within 72 h at static condition. Decolorization time in synthetic 10 g/l molasses. Addition of 5 g/l peptone to NaCl medium had reduced decolorization time from 108 to 72 h. Beef extract do not contribute more to the inducing effect of peptone, however it is a good co-substrate in sucrose or urea containing NaCl medium. Intracellular lignin peroxidase (Lip), laccase and tyrosinase activities were induced by 150, 355 and 212%, respectively till maximum dye removal took place. Aminopyrine N-demethylase (AND) and dichlorophenol indophenol reductase (DCIP-reductase) activities in pd2112 were induced by 130 and 20%, respectively at 72 h of incubation during GHE4B decolorization. By high performance liquid chromatography (HPLC) analysis, 4-hydroxybenzene sulfonic acid and 4-amino, 6-hydroxynaphthalene 2-sulfonic acids were identified as metabolites formed during 24–72 h incubation. Fourier transform infrared spectroscopy (FTIR) analysis supports the formation of these aromatic amines. pd2112, aerobically degraded GHE4B metabolites (formed at static condition) showing stationary phase of 6 days. There was no germination inhibition of Sorghum bicolor and Triticum aestivum by GHE4B metabolites at 3,000 ppm concentration however untreated dye showed germination inhibition at the same concentration. GHE4B metabolites did not show any microbial toxicity at 10,000 ppm concentration.     

Hydrogen Peroxide Production as a Limiting Factor in Xenobiotic Compound Oxidation by Nitrogen-Sufficient Cultures of Bjerkandera sp. Strain BOS55 Overproducing Peroxidases

The overproduction of ligninolytic peroxidase by the N-deregulated white rot fungus Bjerkandera sp. strain BOS55 under nitrogen-sufficient conditions had no noteworthy effect on the oxidation of anthracene or the decolorization of the polymeric aromatic dye Poly R-478 in 6-day-old cultures. Only when the endogenous production of H(inf2)O(inf2) was increased by the addition of extra oxygen and glucose could a 2.5-fold increase in the anthracene oxidation rate and a 6-fold increase in the Poly R-478 decolorization rate be observed in high-N cultures with 10- to 35-fold higher peroxidase activities than N-limited cultures. Further increase of the H(inf2)O(inf2) generation rate in high-N cultures with glucose oxidase led to an additional 3.5-fold increase in the anthracene oxidation rate (350 mg liter(sup-1) day(sup-1)) and a 10-fold increase in the Poly R-478 decolorization rate. These results indicate that xenobiotic compound oxidation by white rot fungi cannot be improved by overproducing peroxidases without increasing the endogenous production of H(inf2)O(inf2). The absence of Mn, which decreased the manganese peroxidase titers and increased the lignin peroxidase titers, was associated with up to 95% improvements in the anthracene oxidation rate. The simultaneous presence of Mn and veratryl alcohol was observed to have a synergistic negative effect on the oxidation of anthracene and the decolorization of Poly R-478.     

Decolorization of synthetic dyes by solid state cultures of Lentinula (Lentinus) edodes producing manganese peroxidase as the main ligninolytic enzyme

The ability of the white-rot fungus Lentinula (Lentinus) edodes to decolorize several synthetic dyes was investigated using solid state cultures with corn cob as substrate. Cultures, containing amido black, congo red, trypan blue, methyl green, remazol brilliant blue R, methyl violet, ethyl violet and Poly R478 at 200 ppm, were completely decolorized after 18 days of incubation. Partial decolorization was observed in the cultures containing 200 ppm of brilliant cresyl blue and methylene blue. High manganese peroxidase activity (2600 U/g substrate), but very low lignin peroxidase (<10 U/g substrate) and laccase (<16 U/g substrate) activities were detected in the cultures. In vitro, the dye decolorization was markedly decreased by the absence of manganic ions and H2O2. These data suggest that manganese peroxidase appear to be the main responsible for the capability of L. edodes to decolorize synthetic dyes.     

Extracellular ligninolytic enzymes by Lentinus polychrous Lév. under solid-state fermentation of potential agro-industrial wastes and their effectiveness in decolorization of synthetic dyes

Six agro-industrial wastes were evaluated as a support for ligninolytic enzyme production by the white-rot fungus Lentinus polychrous Lév. under solid-state fermentation. Enzyme production was markedly different according to the substrate used. Rice bran (RB) yielded the highest laccase activity of 1,449 U/L (after 21 days of culture) with specific activity of 4.4 U/g substrate. Rice bran supplemented with rice husk (RH) (2:1 by wt) showed high laccase activity of 1,425 U/L with specific activity of 10.0 U/g substrate (after 17 days of culture). The crude enzyme of the RH-RB culture also contained manganese peroxidase (MnP) and manganese-independent peroxidase (MIP) activities in relative proportions of 1.9:1.4:1 of laccase:MnP:MIP, respectively. Zymogram studies showed the same isoenzyme pattern with these ligninolytic enzymes. The high enzyme production level and low substrate cost of SSF-L. polychrous Lév. suggest that it has potential for industrial applications. Our studies showed that the crude enzyme from this culture exhibited in vitro decolorization of Indigo Carmine. The highest efficiency of dye decolorization was observed under alkaline conditions (pH 9.0) at an initial dye concentration of 10 mg/L. The rather high pH conditions and high efficiency in Indigo Carmine decolorization make the enzyme further interest for the applications in treatment of waste water from the textile industry, which contains synthetic dyes.     

Influence of aromatic substitution patterns on azo dye degradability by Streptomyces spp. and Phanerochaete chrysosporium.

Twenty-two azo dyes were used to study the influence of substituents on azo dye biodegradability and to explore the possibility of enhancing the biodegradabilities of azo dyes without affecting their properties as dyes by changing their chemical structures. Streptomyces spp. and Phanerochaete chrysosporium were used in the study. None of the actinomycetes (Streptomyces rochei A10, Streptomyces chromofuscus A11, Streptomyces diastaticus A12, S. diastaticus A13, and S. rochei A14) degraded the commercially available Acid Yellow 9. Decolorization of monosulfonated mono azo dye derivatives of azobenzene by the Streptomyces spp. was observed with five azo dyes having the common structural pattern of a hydroxy group in the para position relative to the azo linkage and at least one methoxy and/or one alkyl group in an ortho position relative to the hydroxy group. The fungus P. chrysosporium attacked Acid Yellow 9 to some extent and extensively decolorized several azo dyes. A different pattern was seen for three mono azo dye derivatives of naphthol. Streptomyces spp. decolorized Orange I but not Acid Orange 12 or Orange II. P. chrysosporium, though able to transform these three azo dyes, decolorized Acid Orange 12 and Orange II more effectively than Orange I. A correlation was observed between the rate of decolorization of dyes by Streptomyces spp. and the rate of oxidative decolorization of dyes by a commercial preparation of horseradish peroxidase type II, extracellular peroxidase preparations of S. chromofuscus A11, or Mn(II) peroxidase from P. chrysosporium. Ligninase of P. chrysosporium showed a dye specificity different from that of the other oxidative enzymes.(ABSTRACT TRUNCATED AT 250 WORDS)     

Influence of aromatic substitution patterns on azo dye degradability by Streptomyces spp. and Phanerochaete chrysosporium.

Twenty-two azo dyes were used to study the influence of substituents on azo dye biodegradability and to explore the possibility of enhancing the biodegradabilities of azo dyes without affecting their properties as dyes by changing their chemical structures. Streptomyces spp. and Phanerochaete chrysosporium were used in the study. None of the actinomycetes (Streptomyces rochei A10, Streptomyces chromofuscus A11, Streptomyces diastaticus A12, S. diastaticus A13, and S. rochei A14) degraded the commercially available Acid Yellow 9. Decolorization of monosulfonated mono azo dye derivatives of azobenzene by the Streptomyces spp. was observed with five azo dyes having the common structural pattern of a hydroxy group in the para position relative to the azo linkage and at least one methoxy and/or one alkyl group in an ortho position relative to the hydroxy group. The fungus P. chrysosporium attacked Acid Yellow 9 to some extent and extensively decolorized several azo dyes. A different pattern was seen for three mono azo dye derivatives of naphthol. Streptomyces spp. decolorized Orange I but not Acid Orange 12 or Orange II. P. chrysosporium, though able to transform these three azo dyes, decolorized Acid Orange 12 and Orange II more effectively than Orange I. A correlation was observed between the rate of decolorization of dyes by Streptomyces spp. and the rate of oxidative decolorization of dyes by a commercial preparation of horseradish peroxidase type II, extracellular peroxidase preparations of S. chromofuscus A11, or Mn(II) peroxidase from P. chrysosporium. Ligninase of P. chrysosporium showed a dye specificity different from that of the other oxidative enzymes.(ABSTRACT TRUNCATED AT 250 WORDS)     

Optimization of anaerobically digested distillery molasses spent wash decolorization using soil as inoculum in the absence of additional carbon and nitrogen source

The aim of this study was to achieve maximum decolorization of molasses spent wash (MSW) in absence of any additional carbon or nitrogen source using soil as inoculum. Soil samples were collected from the MSW disposal site. Colored soil samples exhibited higher pH, sugar and protein as compare to less colored samples. A decolorization of 69% was obtained using 10% (w/v) soil and 12.5% (v/v) MSW after 7 days incubation. Optimized parameters including days--6 days, pH--6, MSW--12.5% and soil concentration--40%, were obtained for maximum decolorization. A decolorization of 81% was achieved using 10% soil and 12.5% MSW after 18 days incubation in absence of any media supplement. Nearly 12% reduction in decolorization activity of the soil sample was observed over a period of 12 months when stored at 6 degrees C. It could be concluded that the decolorization of MSW might be achieved using soil as inoculum without addition of chemical amendments.     

Biodegradation of Methyl red by Galactomyces geotrichum MTCC 1360

Galactomyces geotrichum MTCC 1360 can decolorize triphenylmethane, azo and reactive high exhaust textile dyes. At shaking condition this strain showed 100% decolorization of a toxic azo dye Methyl red (100 m gl⁻¹) within 1 h in deionized water at 30 °C. The degradation of Methyl red was possible through a broad pH (3–12) and temperature (5–50 °C) range. Glucose and mycelium concentration had increased the decolorization rate, but the addition of 1 gl⁻¹ molasses in deionized water made decolorization possible in only 10 min. Induction in the NADH–dichloro phenol indophenol (NADH–DCIP) reductase, Malachite green reductase, laccase and lignin peroxidase (Lip) activities were observed in the cells obtained after complete decolorization, showing that there is direct involvement in the degradation of Methyl red. The absence of N-N′-dimethyl-p-phenylenediamine (DMPD) in 5 °C, 2-aminobenzoic acid (ABA) in 50 °C and both the compounds in 30 °C sample have shown the differences in the metabolic fate of Methyl red at different temperatures. The untreated dye at 300 mg l⁻¹ concentration showed 88% germination inhibition in Sorghum bicolor, whereas it was 72% in Triticum aestivum. There was no germination inhibition for both the plants by Methyl red metabolites at 300 mg l⁻¹ concentration.

The scientific relevance of the paper

The azo dye Methyl red (100 mg l⁻¹) was decolorized by G. geotrichum MTCC 1360 within 1 h at shaking condition in deionized water. This organism could decolorize Methyl red at wide pH and temperature ranges. Decolorization time was reduced to 10 min by the addition of molasses to deionized water. There was induction in laccase and Lip, NADH–DCIP reductase and Malachite green reductase activities. The metabolic fate of Methyl red changes with temperature which can be evidenced by the formation of 2-ABA at 5 °C, N-N′-DMPD at 50 °C and both the compounds were absent at 30 °C. Phytotoxicity showed that metabolites of dye had induced shoot and root length of both the tested plants.     

Decolorization of reactive dyes by mixed cultures isolated from textile effluent under anaerobic conditions

In the present study mixed cultures that could grew in the molasses media were isolated from textile dye effluent and its decolorization activity was studied in a batch system under anaerobic conditions, in order to determine the optimal conditions required for the highest decolorization activity. The optimum pH value for decolorization was determined as 8 for all the dyes tested. In the experiment with pH 8 dye decolorizations by mixed cultures were investigated at about 96.2–1031.3 mg l⁻¹ initial dye concentrations. The highest dye removal rates of mixed cultures were 94.9% for Reactive Red RB, 91.0% for Reactive Black B and 63.6% for Remazol Blue at 953.2, 864.9 and 1031.3 mg l⁻¹ initial dye concentrations respectively within 24 h incubation period. When the Reactive Red RB was used, approximately 82–98% total color removal was obtained at between 96.2 and 953.2 mg l⁻¹ initial dye concentrations after 12 h of incubation at 35 °C. These results show that our enriched mixed cultures have the potential to serve as an excellent biomass for the use in reactive dye removal from wastewaters under anaerobic conditions.