Treatment and Detoxification of Aqueous Spruce Bark Extracts by Aspergillus niger

1991 ◽  
Vol 24 (3-4) ◽  
pp. 127-137 ◽  
Author(s):  
J. A. Field ◽  
G. Lettinga
Keyword(s):  
Aspergillus Niger ◽  
Biological Treatment ◽  
Test Organism ◽  
Methanogenic Bacteria ◽  
Toxic Waste ◽  
Gel Chromatography ◽  
Tannin Content ◽  
Waste Streams ◽  
Citrate Buffer ◽  
Spruce Bark

Debarking effluents of the forest industry are severely toxic waste streams due to their high tannin content. The objectives of this study were to evaluate the treatment and detoxification of debarking wastewater with tannin tolerant fungi. For this purpose, Aspergillus niger was cultivated on aqueous bark extracts and the toxicity was assayed utilizing methanogenic bacteria as the test organism. Sterilized aqueous extracts of spruce bark were diluted to 5.2 g COD L−1 (containing 2.7 g tannin COD L−1) in either citrate or tartrate buffer and inoculated with A. niger spores. During four day aerobic fermentations with citrate buffer, the elimination of unfiltered and soluble COD was 28 and 63%, respectively. The apparent yield of biomass averaged 34% of the extract COD; however, 12% of the extract COD was tannins adsorbed on the fungal biomass. The decrease in the tannin concentratio was 50%. According to gel chromatography results, the original oligomeric tannins that resisted biodegradation were those of the highest MW. The toxicity was consequently only partially reduced by the fermentation. During the tartrate buffered fermentations, the pH rose due to the metabolism of the organic acid in the buffer. The rise in pH beyond 6 promoted autoxidative reactions that caused extensive polymerization of the tannins which resisted biodegradation. This resulted not only in an enhanced elimination of the tannins but also in a complete detoxification of the extracts. Similar levels of detoxification could be obtained in sterile un-inoculated extracts by autoxidation alone (raising the pH and aerating the extracts). Likewise, extracts fermented in citrate buffer could be completely detoxified by a subsequent autoxidation treatment. The exclusion peak of the gel chromatograms (MW > 30,000 g mole−1) obtained from the highly autoxidized samples accounted for 53% of the UV absorbance, whereas no exclusion peak was present in the unoxidized extracts. For the biological treatment and detoxification of debarking wastewaters, we recommend the cultivation of tannin tolerant fungi followed by short autoxidation treatments that polymerize the oligomeric tannin fraction resisting biodegradation to non-toxic high molecular weight polymers.

Development of a Pretreatment Program to Improve Biological Treatability of High Strength and Toxic Industrial Wastewater

1994 ◽  
Vol 29 (9) ◽  
pp. 29-37 ◽  
Author(s):  
A. Brenner ◽  
S. Belkin ◽  
A. Abeliovich
Keyword(s):  
Industrial Wastewater ◽  
Biological Treatment ◽  
Treatment Process ◽  
Control Program ◽  
High Strength ◽  
Small Scale ◽  
Waste Streams ◽  
Wastewater Stream ◽  
Biological Treatability ◽  
Biological Treatment Process

A biological treatment process has been suggested as the main treatment stage for a high (organic) strength industrial wastewater stream, discharged by several chemical industries within a large industrial park. Treatability studies have indicated that the wastes contain a fraction of toxic and non-biodegradable organic matter, which limits the implementation of a conventional biological treatment process for the combined wastewater stream. Therefore, an in-plant control program including waste segregation and process-specific pretreatments is proposed. A protocol that enables selection of waste streams amenable to biological treatment and identification of problematic streams requiring pretreatment is presented and demonstrated. It includes simplified laboratory procedures used for chemical and toxicological characterization of source streams originating in various processes. The results can be used for the development of a pretreatment program for problematic waste streams, based upon local small-scale solutions.

TANNINS AND NON-TANNINS OF THE BARKS OF SOME EASTERN CANADIAN CONIFERS, PARTICULARLY WHITE SPRUCE

1938 ◽  
Vol 16b (10) ◽  
pp. 369-379
Author(s):  
W. E. Graham ◽  
A. Rose
Keyword(s):  
Chemical Reactions ◽  
White Spruce ◽  
Group Comparison ◽  
Intensive Study ◽  
Tannin Content ◽  
Standard Methods ◽  
Titration Curves ◽  
Spruce Bark

The tannin content of the barks of several Eastern Canadian conifers has been determined by standard methods in an attempt to assess their value as sources of tanning extracts.A more intensive study has been made of the extractable materials of white spruce bark. The chemical reactions of the extract from this bark show that the tannins therein are typical examples of the catechol or condensed group. Comparison of the ratio of tannin to non-tannins and the buffer index of this extract with the corresponding values for several commercial extracts indicates that the spruce extract would probably be fairly astringent. The titration curves of various fractions of the extract show some indications of the character of the non-tannin constituents.

Biotransformation potential of phytosterols under anoxic and anaerobic conditions

2014 ◽  
Vol 69 (8) ◽  
pp. 1661-1668 ◽  
Author(s):  
C. M. Dykstra ◽  
H. D. Giles ◽  
S. Banerjee ◽  
S. G. Pavlostathis
Keyword(s):  
Free Energy ◽  
Retention Time ◽  
Biological Treatment ◽  
Pulp And Paper ◽  
Standard Gibbs Free Energy ◽  
Group Contribution Method ◽  
Anaerobic Conditions ◽  
Waste Streams ◽  
Sulfate Reducing ◽  
Reducing Conditions

The biotransformation potential of three phytosterols (campesterol, stigmasterol and β-sitosterol) under denitrifying, sulfate-reducing and fermentative/methanogenic conditions was assessed. Using a group contribution method, the standard Gibbs free energy of phytosterols was calculated and used to perform theoretical energetic calculations. The oxidation of phytosterols under aerobic, nitrate-reducing, sulfate-reducing and methanogenic conditions was determined to be energetically feasible. However, using semi-continuously fed cultures maintained at 20–22 °C over 16 weekly feeding cycles (112 days; retention time, 21 days), phytosterol removal was observed under nitrate-reducing and sulfate-reducing conditions, but not under fermentative/methanogenic conditions. Under sulfate-reducing conditions, stigmast-4-en-3-one was identified as an intermediate of phytosterol biotransformation, a reaction more likely carried out by dehydrogenases/isomerases, previously reported to act on cholesterol under both oxic and anoxic (denitrifying) conditions. Further study of the biotransformation of phytosterols under anoxic/anaerobic conditions is necessary to delineate the factors and conditions leading to enhanced phytosterol biodegradation and the development of effective biological treatment systems for the removal of phytosterols from pulp and paper wastewaters and other phytosterol-bearing waste streams.

scholarly journals Detoxification Assays of Tunisian Tannery Wastewater under Nonsterile Conditions Using the Filamentous Fungus Aspergillus niger

2019 ◽  
Vol 2019 ◽  
pp. 1-11 ◽  
Author(s):  
Raouia Boujelben ◽  
Mariem Ellouze ◽  
Sami Sayadi
Keyword(s):  
Aspergillus Niger ◽  
Biological Treatment ◽  
Organic Matter Content ◽  
Matter Content ◽  
Pollution Levels ◽  
Ph Values ◽  
Initial Ph ◽  
Final Effluent ◽  
Mineral Pollution

The ability of Aspergillus niger strain to reduce organic and mineral pollution as well as the toxicity of two tannery wastewaters, the unhairing effluent (UE) and the final effluent (FE), taken from a local Tunisian tannery and under nonsterile conditions, was studied. Raw effluents show alkaline pH ≥11; thus experiments were carried out at initial pH values and at pH adjusted to 6. Characterization of effluents also revealed high salt levels (EC > 17 mS/cm) and high organic matter content (25 g/L for the UE and 7.2 g/L for the FE) but a low biodegradability since BOD5 did not exceed 2.5 and 1.25 g/L for the UE and the FE, respectively. The results of the biological treatment showed that A. niger was able not only to grow at high pH and salinity values, but also to reduce organic and mineral pollutant load. After treatment, the COD reduction for the UE reached 90% and 70% at pH=6 and at initial pH (12.13), respectively. For the FE, the decrease of COD values reached 75% at pH=6 and 64% at initial pH (11.64). Monitoring of mineral pollution levels showed a reduction in chromium (Cr) concentrations reaching 70% for the FE. This was reflected by an increase of the biomass of A. niger from 9.25 g/L (control) to 9.84 g/L for the FE. To confirm the efficiency of the biological treatment using A. niger, phytotoxicity (tomato seeds) and microtoxicity (Escherichia coli and Bacillus subtilis) tests were carried out. Results of this monitoring showed an important decrease in the toxicity levels for both effluents.

Evaluation of the aerobic and anaerobic biodegradability of the antibiotic norfloxacin

2014 ◽  
Vol 70 (2) ◽  
pp. 265-271 ◽  
Author(s):  
Lucilaine Valéria de Souza Santos ◽  
Danusa Campos Teixeira ◽  
Raquel Sampaio Jacob ◽  
Míriam Cristina Santos do Amaral ◽  
Liséte Celina Lange
Keyword(s):  
Anaerobic Digestion ◽  
Industrial Wastewater ◽  
Biological Treatment ◽  
Wastewater Treatment Plants ◽  
Test Organism ◽  
Pharmaceutical Compounds ◽  
Treatment Processes ◽  
Anaerobic Biodegradability ◽  
Aliivibrio Fischeri ◽  
Aerobic And Anaerobic

The purpose of studying the biodegradability of pharmaceutical compounds is to evaluate their behaviors in relation to the treatment processes generally used in domestic and industrial wastewater treatment plants. The antibiotic norfloxacin was found to be a recalcitrant compound. The studies conducted showed norfloxacin removal rates of 12% and 18% when biomasses from treatments with activated sludge and anaerobic biodigesters, respectively, were used without acclimatization. This suggests that anaerobic digestion shows better performance for norfloxacin removal. Ecotoxicological tests, using the luminescent marine bacteria Aliivibrio fischeri as the test organism, show that anaerobic digestion could eliminate the toxicity of the antibiotic norfloxacin, even though total degradation of the drug was not observed. The release of norfloxacin during cell lysis suggests the importance of controlling this phenomenon in biological treatment systems that handle wastewater contaminated with norfloxacin, thus preventing the return of this drug to the environment.

scholarly journals Detoxification and nutritional enrichment of cassava waste pulp using Rhizopus oligosporus and Aspergillus niger

2021 ◽  
Vol 45 (1) ◽  
pp. 52-68
Author(s):  
Adelodun Lawrence Kolapo ◽  
Raoofat Olamide Salami ◽  
Ismail Onajobi ◽  
Flora Emilia Oluwafemi ◽  
Abosede Oyeyemi Fawole ◽  
...  
Keyword(s):  
Aspergillus Niger ◽  
Crude Protein ◽  
Ash Content ◽  
Tannin Content ◽  
Rhizopus Oligosporus ◽  
Natural Fermentation ◽  
Standard Procedures ◽  
Ph Range ◽  
Cassava Varieties ◽  
Cassava Waste

The present study evaluated the detoxification and nutritional enrichment potentials of the fermented cassava waste pulp obtained through different processing methods of sweet (S) and bitter (B) cassava varieties by fermentation with Rhizopus oligosporus and Aspergillus niger. Four batches [two with both bark and cortex of the tuber removed (S- and B-), two with bark only removed (S+ and B+)] of cassava waste pulp (CWP) were produced from each of S and B varieties. CWP from the four treatments were then subjected to Rhizopus oligosporus, Aspergillus niger, and natural fermentation. Cyanide (mg HCN/kg), phytate (mg/100g), tannin (mg/100g), pH, crude protein (N X6.25) (%), ash (%), Fe, P, K and Ca (mg/100g) content of the unfermented and fermented CWP were determined using standard procedures. The range of the reduction (%) in cyanide content for Rhizopus oligosporus fermented CWP (RCWP), Aspergillus niger fermented CWP (ACWP), and naturally fermented CWP (NCWP) were 86.24 – 91.95, 79.68 – 84.34 and 72.96 – 78.58 while those for phytate were 58.82 – 71.20, 29.98 – 39.26 and 36.16 – 40.32 respectively. Fermentation had no significant (p>0.05) effect on the tannin content while the pH range of NCWP, RCWP and ACWP were 7.20 – 7.50, 5.41 – 6.40, and 3.83 – 4.21, respectively. The  range of the increase (%) in the protein content for NCWP, RCWP, and ACWP was 346 – 375 , 671 – 728 and 508 – 542  while those of the ash content were 7.16 – 7.91, 6.72 – 6.84, and 5.42 – 5.63 respectively. Of all the examined minerals, only calcium increased by 5.68 – 26.89, 49.96 - 70.43, and 59.71 – 98.87 % in NCWP, RCWP, and ACWP respectively. Results from the present study are indicating that controlled fermentation offers greater benefit over natural fermentation and that the cassava variety and not the peeling method will determine the extent of detoxification and nutrient enrichment.

scholarly journals Influence of biosynthesized silver nanoparticles on keratinase activity and mycelialgrowth of dermatophytes

2018 ◽  
Vol 9 (SPL1) ◽  
Author(s):  
Adnan Hamad Uobeed Al Hamadani ◽  
Balsam Miri Mizher Al Muhna
Keyword(s):  
Silver Nanoparticles ◽  
Aspergillus Niger ◽  
Antifungal Drugs ◽  
Toxic Waste ◽  
Morphological Alteration ◽  
Microdilution Method ◽  
Broth Microdilution Method ◽  
Activity Comparison ◽  
Cell Free Filtrate

Among different nanomaterial,the silver nanoparticles (SNPs) exhibited high antifungal potency compared with other types of nanoparticles (NPs),and this property is often very helpful,particularly against fungi resistant to conventional antifungal agents. However synthesis of SNPs can generate toxic waste during the preparation process. Accordingly,new technique using non-toxic routs have been researched for synthesis of SNPs using cell-free filtrate of Aspergillus niger and evaluate their effect against some dermatophytes spp.The proposal of our study was to biosynthesize SNPs using cell-free filtrate of Aspergillus niger as reducing agent. The characterization of biosynthesized SNPs were carried out by UV-Visible spectroscopy,Fourier transform infrared spectroscopic analysis (FTIR) and scanning electron microscopy (SEM).The antifungal effect of the NPs against dermatophytes was also evaluated. The minimum inhibitory concentration (MIC) was determined by broth microdilution method. pherical NPs 15-50 nm in size were obtained.The biosynthesized SNPs exerted pronounced morphological alteration in the fungal mycelia.Additionally,the inhibition of keratinase activity of the tested dermatophytes was also recorded.The results indicate that SNps can be synthesized in ecofriendly,inexpensive and promising technique by fungal strain of A.niger,and it has considerable antifungal activity comparison with other antifungal drugs.

scholarly journals Extraction conditions evaluation of pectin methylesterase produced by solid state culture of Aspergillus niger

2019 ◽  
Vol 36 (No. 6) ◽  
pp. 476-479 ◽  
Author(s):  
Valeria Borszcz ◽  
Taísa Renata Piotroski Boscato ◽  
Karine Cenci ◽  
Jamile Zeni ◽  
Rogério Luis Cansian ◽  
...  
Keyword(s):  
Solid State ◽  
Aspergillus Niger ◽  
Tween 80 ◽  
Pectin Methylesterase ◽  
Citrate Buffer ◽  
State Culture ◽  
Independent Variables ◽  
Solid State Culture ◽  
Extraction Cycle ◽  
Central Composite

Different solvents and extraction solutions (distilled water, NaCl, Tween 80, citrate buffer, and acetate buffer) were evaluated for enzymes recovery. The independent variables evaluated were agitation (12–348 rpm), time (4.8–55.2 min), and temperature (13.2–46.8°C) and 10 extraction cycles, using an experimental design (Central composite rotatable design 2<sup>3</sup>). Pectin methyl esterase maximum recovery by solid state culture of Aspergillus niger was 11 U/g<sub>wm</sub> (31 U/g<sub>dm</sub>) using NaCl (0.1 mol/l) as solvent at a 5 : 1 (v/w) ratio, 30°C for 55.2 min, at 180 rpm, with one extraction cycle.

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