Degradation Of Tannic Acid Research Articles

Optimization of chromium and tannic acid bioremediation by Aspergillus niveus using Plackett\u2013Burman design and response surface methodology

A chromium and tannic acid resistance fungal strain was isolated from tannery effluent, and identified as Aspergillus niveus MCC 1318 based on its rDNA gene sequence. The MIC (minimum inhibitory concentration) of the isolate against chromium and tannic acid was found to be 200 ppm and 5% respectively. Optimization of physiochemical parameters for biosorption of chromium and tannic acid degradation was carried out by Plackett–Burman design followed by response surface methodology (RSM). The maximum chromium removal and tannic acid degradation was found to be 92 and 68% respectively by A. niveus. Chromium removal and tannic acid degradation was increased up to 11 and 6% respectively after optimization. Scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR) was used to investigate biosorption phenomena.

Evaluation of model parameters for growth, tannic acid utilization and tannase production in Bacillus gottheilii M2S2 using polyurethane foam blocks as support.

Production of tannase from B. gottheilii M2S2 was studied under solid-state fermentation with an optimized medium consisting of polyurethane foam matrix of dimension 40×40×5mm, impregnated with a liquid medium comprising (w/v): 4% tannic acid; 2% NH4NO3; 0.1% KH2PO4; 0.2% MgSO4; 0.1% NaCl and 0.05% CaCl2·2H2O in distilled water, having a pH of 4.7. Maximum tannase production of 56.87 U/L was obtained after 32h of fermentation at 32°C in static condition. This study deals with the evaluation of unstructured kinetic models to understand the behavior of biomass, tannase production and tannic acid degradation, with the fermentation time. The growth rate of B. gottheilii M2S2 was 0.0703h-1 at 32h of fermentation. Product (Yx/s) and biomass yield (Yp/s) coefficients were estimated as 1.77 U/g of tannic acid and 0.276g of biomass/g of tannic acid. All the kinetic constants µ, α, β, m and n were evaluated using MATLAB 2015Rb program. The experimental and model-generated data showed a good correlation, which indicated that these models will describe tannase production and fermentation process.

Efficient degradation of tannic acid in water by UV/H 2 O 2 process

In this work, the degradation of tannic acid (TA) by UV/H2O2 process has been investigated. UV/H2O2 oxidation experiments were performed by UV irradiation at 254 nm of TA aqueous solutions in a photo-reactor. Firstly, the effects of certain parameters including pH, H2O2 content, and temperature on the decomposition of H2O2 during UV/H2O2 process were evaluated. Results obtained showed that UV-irradiation of 1 g H2O2 L−1 aqueous solution achieved almost complete decomposition of H2O2 (> 98%) at pH = 5 and 28 °C. H2O2 decomposition follows pseudo-first-order kinetics with a rate constant of 0.0086 min−1 under the optimal conditions. Secondly, the degradation of TA by UV/H2O2 process was investigated. The effects of certain operating conditions including initial pH, temperature, H2O2 concentration and initial total organic carbon (TOC) on the efficiency of degradation and mineralization of TA by UV/H2O2 were evaluated. The results showed that UV/H2O2 process achieved almost complete disappearance of the absorbance at 276 nm (> 96%) and high TOC removal (94%) from TA aqueous solutions containing 82 mg C L−1 under pH = 9 using 6 g H2O2 L−1 at 28 °C. The results confirmed that the degradation and mineralization of TA molecules in water occur via chemical oxidation with hydroxyl radicals produced by photo-decomposition of H2O2 by UV light. Chromatography analysis revealed that the mechanism of TA degradation involves several steps including the formation of gallic acid and pyrogallol. These aromatic intermediates undergo further oxidative ring opening to form carboxylic acids (oxalic and maleic acids) that end up to be completely mineralized. The electrical energy requirement consumed under the optimal conditions was 7.9 kWh g−1 TOC which is highly competitive with other advanced oxidation technologies such as ozonation and UV/O3 processes. Based on these results, it can be concluded that UV/H2O2 can be considered as a cost-effective method to treat wastewaters contaminated with natural organic matter.

Nutrient assessment of olive leaf residues processed by solid-state fermentation as an innovative feedstuff additive.

Olive leaf residue feedstuff additives were prepared by solid-state fermentation (SSF), and its feeding effects on broiler chickens were examined. The fermentation's nutrient value, that is, protein enrichment, cellulase activity, tannic acid degradation and amino acid enhancement, was determined. The effect of different strains, including molds (Aspergillus niger, Aspergillus oryzae and Trichoderma viride) and yeasts (Candida utilis, Candida tropicalis and Geotrichum candidum), and the fermentation time on the nutrient values of the feedstuff additives was investigated. The experimental results showed that the optimal parameters for best performance were A.niger and C.utilis in a 1:1 ratio (v/v) in co-culture fermentation for 5days. Under these conditions, the total content of amino acids in the fermented olive leaf residues increased by 22·0% in comparison with that in the raw leaf residues. Both Glutamic acid and Aspartic acid contents were increased by more than 25·4%. Broiler chickens fed with different amounts of feedstuff additives were assessed. The results demonstrated that the chicken weight gains increased by 120%, and normal serum biochemical parameters were improved significantly after 10% of the feedstuff additives were supplemented to the daily chicken feed for 28days. The co-culture combination of A.niger and C.utilis with SSF for olive leaf residue had the best nutrient values. The addition of 10% fermented olive leaf residue facilitated the chicken growth and development. This study reveals that olive leaf residues fermented by SSF exhibited considerable potential as feed additives for feeding poultry.

Interaction of tannic acid with ferric iron to assist 2,4,6-trichlorophenol catalytic decomposition and reuse of ferric sludge as a source of iron catalyst in Fenton-based treatment

A comprehensive study of the catalytic behaviour of Fe3+ in the presence of tannic acid during the Fenton-based treatment of chlorophenols-contaminated water was performed. The ability of the iron-containing sludge to catalyse the Fenton-based process was assessed and the mechanistic behaviour of tannic acid in the iron dissolution was evaluated.Tannic acid, a constituent of pulp and paper industry water effluent and natural water, enhanced the 2,4,6-trichlorophenol catalytic decomposition in Fe3+-activated H2O2 oxidation system by reducing of the Fe3+. The Fe3+ reductive mechanism by tannic acid incorporated tannic acid–Fe3+ complex formation and decay through an electron transfer reaction to form Fe2+. An indirect measurement of hydroxyl radical (HO) by the deoxyribose method indicated a considerable increase in HO by Fe3+/H2O2 in the presence of tannic acid. A pseudo-first reaction rate constant of 2,4,6-trichlorophenol degradation by Fe2+/H2O2 was high and close to that of Fe3+/H2O2 with tannic acid. Degradation of tannic acid along with that of 2,4,6-trichlorophenol required optimization of H2O2 and Fe3+ dosages to balance HO formation and scavenging.Acidic reaction media (pH 3.0) and the presence of tannic acid favoured 2,4,6-trichlorophenol degradation by H2O2 oxidation induced by iron dissolved from ferric oxyhydroxide sludge. The reuse of ferric oxyhydroxide sludge as a catalyst source in the Fenton–based process can minimise the production of hazardous solid waste and the overall cost of the treatment.This study highlights the ability of tannic acid-Fe3+ complexes to participate in Fe3+ reductive pathway and, as a result, to allow reuse of non-regenerated ferric oxyhydroxide sludge for activation of H2O2 oxidation in wastewater treatment at acidic pH.

The efficacy of tannic acid in controlling biofouling by Pseudomonas aeruginosa is dependent on nutrient conditions and bacterial density

This study investigated the effect of tannic acid (TA) on biofilm formation by Pseudomonas aeruginosa PAO1 as a model organism. Here, we report that TA enhanced biofilm formation in M9 medium at a bacterial concentration of 0.1 (OD600) on different model surfaces such as: polystyrene microtiter plate, polypropylene tube and borosilicate glass tube. However, TA reduced biofilm formation by PAO1 in M9 and yeast nutrient broth (YNB) media at a bacterial concentration of 0.001 (OD600). Strikingly, TA reduced biofilm formation at a bacterial concentration of 0.01 (OD600) in YNB medium but increased biofilm formation in M9 medium. When yeast extract (10 g/l) was added to the M9 medium TA reduced biofilm formation (51.0%). These trends were confirmed qualitatively and quantitatively by confocal microscopy. In the presence of yeast extract, TA exhibited 89.0% biofilm biovolume reduction compared to the untreated control. When yeast extract, tryptone and l-arginine were added to M9 medium, TA showed anti-biofilm activity at all bacterial densities tested. When tannase was added, the anti-biofilm efficacy of TA decreased. Furthermore, organic nitrogen limitation triggered TA degradation in the cultures (P < 0.05), which in turn restored biofilm formation. These results suggest that bacterial density and nutritional conditions are critical to the anti-biofilm efficacy of TA against PAO1 and thus may explain differences in the literature regarding the effect of TA on biofilm formation.

Unraveling the mechanism of thermal and thermo-oxidative degradation of tannic acid

The thermal and thermo-oxidative degradation of hydrolysable tannin, i.e. tannic acid is reported. The study on thermal and thermo-oxidative degradation mechanism of tannic acid was carried out by using several advanced thermal characterization techniques such as Thermogravimetric analysis (TGA) coupled with Fourier-Transform Infrared (FTIR) Spectroscopy (TGA–FTIR), pyrolysis–gas chromatography–mass spectroscopy (Py–GC–MS) and Attenuated Total Reflectance (ATR)–FTIR. The condensed phase and gaseous phase degradation studies were combined to deduce a probable degradation pathway for tannic acid molecule at high temperature under nitrogen and air atmosphere.

Application of UVA-LED based photocatalysis for plywood mill wastewater treatment

The batch mode UVA-LED photocatalytic reactor with recirculation was tested for formic acid (0.22mM) and phenol (0.1mM) degradation using commercially available titanium dioxide. Decomposition of model molecules was monitored by means of high pressure liquid chromatography (HPLC), total organic carbon analyzer (TOC) and chemical oxygen demand (COD). Apparent quantum yields for formic acid and phenol were estimated to be 0.8% and 0.98%, respectively. Also, plywood mill effluent treatment was performed using chosen reactor. Primary degradation of tannic acid, as well as TOC and COD removal were monitored in the course of an experiment. About 72% and 60% of COD and TOC removal was achieved, respectively, after 60min of irradiation at TiO2 loading 0.5gL−1. The evolution of average oxidation state of carbon atoms was estimated for plywood mill wastewater.

One-step hydrothermal synthesis of iron and nitrogen co-doped TiO2nanotubes with enhanced visible-light photocatalytic activity

TiO2 nanotubes co-doped with iron and nitrogen were successfully synthesized with commercial TiO2 powders (CTPs) using a one-step hydrothermal method. The morphology, structure and composition of the as-prepared nanotubes were characterized using transmission electron microscopy (TEM), field emission scanning electron microscopy (FESEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), UV-vis diffuse reflectance spectroscopy (UV-vis), photoluminescence (PL) spectroscopy and Raman spectroscopy. The photocatalytic activities of the samples are evaluated for the degradation of tannic acid (TA, 25 mg L−1) in aqueous solutions under visible light (λ > 420 nm). The results of TEM suggest that all the samples present a diameter of approximately 9 nm and a length of approximately 200–600 nm. The results of XRD suggest that the predominant phase of all the as-prepared samples was the anatase crystal. The XPS results indicate that Fe and N were successfully introduced into the TiO2 nanotubes (TNTs). Compared with the CTPs and pure TNTs, the Fe and N co-doped TiO2 nanotubes (Fe/N-TNTs) exhibit a stronger visible-light absorption capability, and an enhanced photocatalytic activity toward the photodegradation of TA aqueous solution under visible-light irradiation. Notably, the xFe/N-TNT catalysts can be easily recycled due to their one-dimensional nanostructural properties.

Production profiles of phenolics from fungal tannic acid biodegradation in submerged and solid-state fermentation

Potent antioxidant phenolics are derived from tannin biodegradation. Understanding of biodegradation pathways through the identification of the intermediates molecules of great value like tannins is important to pursuit the production of bioactive monomers. Biodegradation of tannins remains poorly understood due to their chemical complexity and reactivity. Tannic acid biodegradation by Aspergillus niger GH1 in submerged fermentation (SF) and solid state fermentation (SSF) was evaluated by liquid chromatography coupled to mass spectrometry (LC–MS). Both cultures were kinetically monitored for the biodegradation profiles during 72h. Differences in tannic acid composition were evidenced and the consumption of substrate and identification of biodegradation intermediates were achieved. The mechanism of tannic acid degradation by A. niger GH1 is by degradation of high molecular weight gallotannins and highly polymerized tannins to small molecules like gallic acid, digalloyl glucose and trigalloyl glucose. Important differences on time of substrate uptake and product release were revealed.

Degradation of Tannic Acid Using TiO2 Nanotubes as Electrocatalyst

Structured TiO2 nanotubes were grown on 2 mm thick titanium sheet by anodization of titanium in ethylene glycol medium containing 0.025 M NaF. The morphology of TiO2 nanotubes (TNT) was characterized using field emission scanning electron microscope. The potential of TNT as anode and also as photocatalyst for the degradation of tannic acid was studied. The mineralization of tannic acid was measured in terms Total Organic Carbon (TOC). Only 50% of TOC could be removed by exposing the tannic acid solution to UV-radiation (photolysis), whereas it was improved to 70% by electrooxidation (EO) using TNT as anode. Maximum degradation of 83% was achieved when electrooxidation was conducted under the influence of UV-radiation (photoelectrocatalytic process (PEC)). Among the electrolytes tried, Na2SO4 was observed to be very effective for the degradation of tannic acid. The kinetics of tannic acid degradation by photoelectrocatalytic process was found to follow zero-order rate expression.

Photocatalytic Degradation of Phytotoxic Substances in Waste Nutrient Solution by Various Immobilized Levels of Nano-TiO2

The photocatalytic degradation effectiveness of six selected typical phytotoxic substances (ferulic, benzoic, gallic, salicylic, tannic, and acetic acid) by two levels of 10 nm TiO2 (11 and 22 g/m2) immobilized on tiles under 254 nm of UV light irradiation was investigated. The results showed that the immobilized nano-TiO2 significantly degraded all phytotoxic substances dissolved in distilled water, and the cumulative degradation rates of ferulic, benzoic, gallic, salicylic, tannic, and acetic acid reached 22.2, 33.6, 48.2, 56.9, 57.5, and 76.0 % after 6 h of treatment, respectively. Furthermore, the cumulative degradation rates of six phytotoxic substances by immobilized nano-TiO2 were different remarkably, i.e., salicylic acid > benzoic acid, gallic acid > ferulic acid, acetic acid > tannic acid. The maximal photocatalytic degradation efficiencies of all phytotoxic substances appeared at the first 2 h in the three experiments. During the 6-h treatment period, the photocatalytic degradation efficiency of all phytotoxic substances decreased gradually. There was no significant difference in the photocatalytic degradation of benzoic acid and ferulic acid between the two levels of immobilized nano-TiO2 treatments, whereas a significant difference was found in the photocatalytic degradation of salicylic acid, gallic acid, tannic acid, and acetic acid. In a word, nano-TiO2 photocatalysis is an effective method to degrade phytotoxic substances. And the photocatalytic degradation effectiveness of six typical phytotoxic substances may be related to their structures.

Degradation of Tannic Acid Powered by TiO&lt;sub&gt;2&lt;/sub&gt; Nanoparticles

The wastewater from the coir, pharmaceutical, leather, paper and pulp industries is contaminated with water-soluble poly phenolic compounds (tannins). Among various tannins, tannic acid is a typical hydrolysable tannin prevalent in wastewater. The degradation of tannic acid using TiO2 nanoparticles as photocatalyst was investigated. The effect of catalyst concentration, pH of aqueous suspension and also electron acceptors such as hydrogen peroxide (H2O2) and ozone (O3) on the degradation of tannic acid was studied. The degradation of tannic acid was found to be more efficient and complete in the presence of UV/TiO2/O3 compared to UV/TiO2/H2O2. The kinetics of degradation was observed to follow first order rate equation which indicates that the mineralization process is diffusion controlled.

Tannase activity from the marine cyanobacterium Phormidium valderianum BDU140441

The marine cyanobacterium Phormidium valderianum BDU 140441 exhibited the ability to grow at 0.25 mM tannic acid, a known hindering chemical for microbial growth. The tannic acid-degrading ability of the organism is evident from the UV–visible absorption spectrum. In addition, the existence of tannase has been localized by activity staining, and its induction in activity upon tannic acid exposure was confirmed in native gel. The critical tannic acid metabolization enzymes tested for are polyphenol oxidase and esterases; both are well known for tannic acid degradation. Upon tannic acid exposure, increased activity of polyphenol oxidase and expression of few new isoforms of esterase were identified by activity staining.

Degradation of tannic acid and purification and characterization of tannase from Enterococcus faecalis

Tannins, present in various foods, feeds and forages, have anti-nutritional activity; however, presence of tannase in microorganisms inhabiting rumen and gastrointestinal tract of animals results in detoxification of these tannins. The present investigation was carried out to study the degradation profile of tannins by Enterococcus faecalis and to purify tannase. E. faecalis was observed to degrade tannic acid (1.0% in minimal media) to gallic acid, pyrogallol and resorcinol. Tannase from E. faecalis was purified up to 18.7 folds, with a recovery of 41.7%, using ammonium sulphate precipitation, followed by DEAE-cellulose and Sephadex G-150. The 45 kDa protein had an optimum activity at 40 °C and pH 6.0 at substrate concentration of 0.25 mM methyl gallate.

Gluconacetobacter hansenii UAC09-mediated transformation of polyphenols and pectin of coffee cherry husk extract

Gluconacetobacter, a bacterial cellulose (BC)-producing organism, has ability to utilise pectin and phenolic compounds. The extract of coffee cherry husk (CCH), a high pectin- and polyphenol-containing agro waste was used in the study. Production of endo- and exo-polygalacturonase, polyphenol oxidase and tannase was observed during fermentation. Co-utilisation of glucose and galacturonic acid was observed. Accumulation of rhamnose, arabinose and galactose indicated the breakdown of pectin. Among the phenolic acids, benzoic acid derivatives were found to be degraded faster than cinnamic acid derivatives. Degradation of tannic acid was more pronounced among the bound forms than free forms in the culture broth. In BC, accumulation of free tannic, gentisic and coumaric acids was observed during the 2nd week of fermentation. The present work indicates the ability of the organism to produce BC by the utilisation of agro waste like CCH.

Degradation of tannic acid by cold-adapted Klebsiella sp NACASA1 and phytotoxicity assessment of tannic acid and its degradation products

The focus of the present study is to know the potential of bacterial isolate for tannic acid degradation at low temperature. Also, we tried to evaluate the suitability of phytotoxicity testing protocol for the determination of tannic acid toxicity. Screening for tannic acid degrading bacterial strains was carried out by using microbial isolation techniques. The 16S rDNA amplicon of the isolate was used to identify the isolate. The effect of different concentrations of tannic acid and its degradation products on germination of Vigna unguiculata was evaluated. The study was carried out to determine total sugar and starch content of the used seeds and even to check the presence of α-amylase activity during seed germination. The isolated bacterium was identified as Klebsiella sp NACASA1 and it showed degradation of tannic acid in 40 (±0.85***) h at 15°C and pH7.0. A gradual decrease in root/shoot length was observed with increasing concentration of tannic acid. There was 95.11 (±0.24**)% inhibition in α-amylase activity at 20,000ppm tannic acid, as compared to control. No such effects were observed on germination, root-shoot length, and α-amylase activity with tannic acid degradation products. The results obtained confirmed that tannic acid may act as a toxic agent in plant cells. The simple biodegradation process presented in this study was found to be effective in reducing toxicity of tannic acid. Also, it reveals the potential of soil bacterium to degrade tannic acid at low temperature.

Electrochemical oxidation of tannic acid contaminated wastewater by RuO2/IrO2/TaO2‐coated titanium and graphite anodes

The electrochemical oxidation of tannic acid contaminated wastewater by RuO2/IrO2/TaO2‐coated titanium and graphite anodes has been investigated. The effect of the process variables, such as initial pH, current density, processing time, concentration of the electrolyte and anode materials, on the degradation of tannic acid was studied. During the various stages of electrolysis, parameters such as COD, chloride ion concentration and UV–Vis spectra were examined and discussed. The maximum chemical oxygen demand (COD) removal efficiency of 94% was achieved at pH 5, operated at the current density of 8.10 mA/cm2, electrolyte (NaCl) concentration of 0.1 M and at 60 min of electrolysis using graphite anodes. The experimental results showed that the electrochemical oxidation process could effectively reduce the COD from the tannic acid contaminated wastewater. An acidic pH showed the maximum reduction of COD compared with neutral and alkaline pH. Increase in current density, process time and electrolyte (NaCl) concentration with the increase in COD removal. Graphite anodes showed maximum removal of COD and better tannic acid degradation when compared with RuO2/IrO2/TaO2‐coated titanium anodes.

A novel and sensitive plate assay for screening of tannase-producing bacteria

In the present investigation, a new method for isolation and selective screening of tanninolytic, i.e. tannase-producing, bacteria was developed and compared with the earlier prevalent method. Tannase-producing bacteria were screened on agar plates using a newly developed plate assay method in which tannase cleaves the tannin–protein complex formed by addition of tannic acid to the medium, and forms a greenish brown zone around the bacterial colony due to the degradation of tannic acid. Using conventional methods, the zone formed was not clearly visible and pigmentation development took 3–4 days; however, the new method yielded clearer and more sensitive results within a shorter incubation time of 48–72 h.

Tannic acid degradation by bacterial strains Serratia spp. and Pantoea sp. isolated from olive mill waste mixtures

A mixture made of Olive Mill Waste (OMW) and hygroscopic organic additives was stored in indoor and outdoor stack piles. A significant decrease in organic matter and polyphenols was detected in indoor stack pile (51.5% and 75% of initial contents, respectively). Three bacterial strains isolated from OMW indoor stack pile were able to grow in the presence of tannic acid as sole carbon and energy source, and were named 2AT1, 2AT2, and 2AT3. 16S rRNA gene sequencing assigned isolates 2AT1 and 2AT3 to the genus Serratia, and strain 2AT2 to the genus Pantoea. The highest tannase activity was pointed out in the Pantoea sp. strain 2AT2, and growth tests showed a maximum degradation rates of tannic acid within 6 h and a complete depletion in 24 h for all isolates. Glucose and gallic acid were detected in the bacterial cultures as breakdown products of tannic acid added to the mineral culture-medium as the sole carbon and energy source. This was the first evidence of bacterial strains able to degrade tannic acid isolated from OMW.