Refine search
Results 1-10 of 16
Demonstration of a plant-microbe integrated system for treatment of real-time textile industry wastewater
2022
Jayapal, Mohanapriya | Jagadeesan, Hema | Krishnasamy, Vinothkumar | Shanmugam, Gomathi | Muniyappan, Vignesh | Chidambaram, Dinesh | Krishnamurthy, Satheesh
The real-time textile dyes wastewater contains hazardous and recalcitrant chemicals that are difficult to degrade by conventional methods. Such pollutants, when released without proper treatment into the environment, impact water quality and usage. Hence, the textile dye effluent is considered a severe environmental pollutant. It contains mixed contaminants like dyes, sodium bicarbonate, acetic acid. The physico-chemical treatment of these wastewaters produces a large amount of sludge and costly. Acceptance of technology by the industry mandates that it should be efficient, cost-effective and the treated water is safe for reuse. A sequential anaerobic-aerobic plant-microbe system with acclimatized microorganisms and vetiver plants, was evaluated at a pilot-scale on-site. At the end of the sequential process, decolorization and total aromatic amine (TAA) removal were 78.8% and 69.2% respectively. Analysis of the treated water at various stages using Fourier Transform Infrared (FTIR), High Performance Liquid Chromatography (HPLC)) Gas Chromatography-Mass Spectrometry (GC-MS) Liquid Chromatography-Mass Spectrometry (LC-MS) indicated that the dyes were decolourized and the aromatic amine intermediates formed were degraded to give aliphatic compounds. Scanning Electron Microscope (SEM) and Atomic Force Microscopy (AFM) analysis showed interaction of microbe with the roots of vetiver plants. Toxicity analysis with zebrafish indicated the removal of toxins and teratogens.
Show more [+] Less [-]Resistance of blended alkali-activated fly ash-OPC mortar to mild-concentration sulfuric and acetic acid attack
2022
The traditional cementitious product is prone to suffer from a high degree of deterioration in the case of exposure to acid solutions because of the decomposition of the binder network. However, the degradation of concrete structures in service by mild concentrations of acid under conditions involving sewage, industrial waters, and acid rain is more common and results in a significant environmental problem. The utilization of alkali-activated materials has been seen to potentially offer an attractive option with regard to acceptable durability and a low carbon footprint. With the aid of visual observation, mass loss, compressive strength tests, X-ray diffraction, Fourier transform infrared spectroscopy, and field-emission scanning electron microscopy with energy-dispersive X-ray spectroscopy, the acid resistance of alkali-activated fly ash mortars in which the precursor was partially replaced (0–30% by mass proportion) with ordinary Portland cement (OPC) was evaluated after 180 days of exposure to mild-concentration sulfuric and acetic solutions (pH = 3). A conventional cement mortar (100% OPC) was used as a reference group. The results demonstrate that the addition of OPC into the alkali-activated system causes a significant increase in compressive strength (around 16.08–36.61%) while showing an opposite influence on durability after acid attack. Based on a linear mean value and nonlinear artificial neural network model simulation, the mass losses of the specimens were evaluated, and the alkali-activated pure-fly ash mortar demonstrated the lowest value (i.e., a maximum of 5.61%) together with the best behavior in the aspect of discreteness at 180 days. The results from microstructure analysis show that the coexistence of the N–A–S–H and C–S–H networks in the blend system occurred by both OPC hydration and FA. However, the formation of the gypsum deposition within the fly ash-OPC blend systems at sulfuric acid was found to impose internal disintegrating stresses, causing a significant area of delamination and cracks. In addition, alkali metal ion leaching, dealumination, as well as the disappearance of some crystalline phases occurred in specimens immersed in both types of acids.
Show more [+] Less [-]Augmentation characteristics and microbial community dynamics of low temperature resistant composite strains LTF-27
2022
Boboua, Stopira Yannick Benz | Zhou, Chenyang | Li, Jiachen | Bi, Weishuai | Wang, Ruxian | Chen, Shengnan | Zheng, Guoxiang
Biogas production in the cold regions of China is hindered by low temperatures, which led to slow lignocellulose biotransformation. Cold-adapted lignocellulose degrading microbial complex community LTF-27 was used to investigate the influence of hydrolysis on biogas production. After 5 days of hydrolysis at 15 ± 1 °C, the hydrolysis conversion rate of the corn straw went up to 22.64%, and the concentration of acetic acid increased to 2596.56 mg/L. The methane production rates of total solids (TS) inoculated by LTF-27 reached 204.72 mL/g, which was higher than the biogas (161.34 mL/g), and the control group (CK) inoculated with cultural solution (121.19 mL/g), the methane production rate of volatile solids (VS) increased by 26.88% and 68.92%, respectively. Parabacteroides, Lysinibacillus, and Citrobacter were the main organisms that were responsible for hydrolysis. While numerous other bacteria genera in the gas-producing phase, Macellibacteroides were the most commonly occurring one. Methanosarcina and Methanobacteriaceae contributed 86.25% and 11.80% of the total Archaea abundance during this phase. This study proves the psychrotrophic LTF-27’s applicability in hydrolysis and biomass gas production in low temperatures.
Show more [+] Less [-]Valorization of rubberwood sawdust and sewage sludge by pyrolysis and co-pyrolysis using agitated bed reactor for producing biofuel or value-added products
2022
Ali, Liaqat | Palamanit, Arkom | Techato, Kuaanan | Baloch, Khurshid Ahmed | Jutidamrongphan, Warangkana
This study investigated experimentally pyrolysis of rubberwood sawdust (RWS), sewage sludge (SS), and their blends (25:75, 50:50, and 75:25 by weight) in an agitated bed pyrolysis reactor. The yields and characteristics of liquid product and biochar were determined for pyrolysis at 450, 500, and 550 °C and were affected both by temperature and feedstock type. The liquid and biochar yields were in the ranges 27.30–52.42 and 21.43–49.66 (wt%). Pyrolysis of RWS at 550 °C provided the highest liquid yield, while SS gave a high biochar yield. Co-pyrolysis of SS with RWS improved yield and quality of liquid and biochar products. The liquid product had 57.54–70.70 wt% of water and a low hydrocarbon content. The higher heating value (HHV) of water-free liquid product was 14.73–22.45 MJ/kg. The major compounds of liquid product included acetic acid, 2-propanone, 1-hydroxy, and phenols according to GC-MS. The biochar from RWS had a high carbon content (83.37 wt%) and a high HHV (33.57 MJ/kg), while SS biochar was mainly ash (67.62 wt%) with low carbon content. The SS biochar also had high contents of Si, Ca, Fe, K, and Mg as determined by XRF. Co-pyrolysis of SS with RWS improved the biochar by increasing its carbon content and reducing ash and inorganic elements. The surface of RWS biochar was more porous, while SS biochar had the larger specific surface according to SEM and BET. Based on these results, co-pyrolysis of 75:25 feedstock mix is recommended for further studies on applications of liquid product and biochar.
Show more [+] Less [-]Study of controlled migration of cadmium and lead into foods from plastic utensils for children
2022
Pereira, Elizeu Chiodi | Leroux, Isabelle Nogueira | Luz, Maciel Santos | Batista, Bruno Lemos | Olympio, Kelly Polido Kaneshiro
Lead (Pb) is a highly neurotoxic chemical element known for reducing intelligence quotient (IQ) and promoting antisocial behavior in children and adolescents, while cadmium (Cd) is a carcinogenic bioaccumulative element. Both these metals are included in the priority pollutant list of the United States Environmental Protection Agency and in the WHO List of Chemicals of Major Public Health Concern, where contaminated foods and beverages are the most common pathways of exposure. The objective of this study was to determine total Cd and Pb levels in colored plastic utensils (cups, mugs, bowls, feeding bottles, and plates) for use by children and to measure the specific migration of these elements into beverages and foods. Total contaminant levels were determined using a handheld X-ray fluorescence analyzer. Specific migration tests were conducted using the simulant solutions acetic acid 3% (m/v) and water. Migration levels were determined by ICP-MS. Specific migration tests for Pb were also performed on commercially available samples (cola soft drink, orange juice, vinegar, and milk), with levels determined by graphite-furnace atomic absorption spectrometry (GF-AAS). A total of 674 utensils were analyzed in loco at major commercial centers in Greater São Paulo, of which 87 were purchased for containing Cd and Pb concentrations above permitted limits. Mean concentrations of the metals detected in the purchased utensils were 1110 ppm for Pb and 338 ppm for Cd. For specific migration assays, Pb levels were 187, 13, and 380 times above the permitted limit (0.01 mg.kg -1) for acetic acid, water, and orange juice, respectively. Cd levels were 50 and 2.4 times above the maximum permitted limit (0.005 mg.kg -1) for acetic acid and water, respectively. The districts where the utensils were purchased were grouped according to their social vulnerability index and compared using ANOVA. Pb levels were different between low and medium/high social vulnerability groups (p = 0.006). The findings corroborate the initial hypothesis that these utensils constitute a major source of exposure to PTEs such as Cd and Pb, pointing to the need for stricter regulation and inspection by the Brazilian regulatory agencies.
Show more [+] Less [-]Flavocoxid halts both intestinal and extraintestinal alterations in acetic acid-induced colitis in rats
2022
Mohamed, Nagwa I. | El-Kashef, Dalia H. | Suddek, Ghada M.
Ulcerative colitis (UC) is an idiopathic chronic inflammatory disorder mainly affecting the colon and rectum. The present investigation was undertaken to evaluate the potential protective effect of flavocoxid, a dual COX and LOX inhibitor, in colitis model in rats. UC was induced by instillation of 2 ml of 4% acetic acid (AA) into the colon using a pediatric catheter in rats, and flavocoxid (10 and 20 mg·kg⁻¹) was given once daily for 7 days before induction of colitis. Rats were sacrificed; sera were collected; colons and livers were isolated and then analyzed by biochemical, macroscopic, and histopathological examination. Pretreatment with flavocoxid (10 and 20 mg·kg⁻¹) significantly reduced serum levels of alanine transaminase (ALT) (43.7 ± 7 and 76.2 ± 7.3 vs. 288.7 ± 31.4 in AA group) and aspartate transaminase (AST) (179.5 ± 22.2 and 200.5 ± 14 vs. 392.7 ± 35.6 in AA group) (p>0.05). Also, it decreased malondialdehyde (MDA) and nitric oxide (NOx) levels in both colonic and hepatic tissues. Moreover, flavocoxid effectively elevated colonic and hepatic reduced glutathione (GSH) level and superoxide dismutase (SOD) activity when compared to AA group (p>0.05). Additionally, flavocoxid significantly decreased levels of tumor necrosis factor-α (TNF-α) (878.2 ± 13.4 and 560.1 ± 2.9 vs. 1378.1 ± 31 in AA group) in colonic tissues and (701 ± 6.9 and 442.5 ± 8.2 vs. 1501 ± 9.4 in AA group) in hepatic tissues, nuclear factor kappa B (NF-κBp65) (493.8 ± 6.8 and 368.7 ± 3.1 vs. 659.2 ± 9.4 in AA group) in colonic tissues and (358 ± 5.1 and 163.5 ± 7.8 vs. 732.5 ± 4.5 in AA group) in hepatic tissues, myeloperoxidase (MPO) (15.7 ± 0.3 and 13 ± 0.2 vs. 20.9 ± 0.5 in AA group) in colonic tissues and (20.4 ± 0.3 and 16.3 ± 0.3 vs. 23.9 ± 1.2 in AA group) in hepatic tissues, and inducible nitric oxide synthase (iNOS) (12.5 ± 0.3 and 10 ± 0.2 vs. 16 ± 0.1 in AA group) in colonic tissues and (14.1 ± 0.04 and 11.5 ± 0.08 vs. 17.8 ± 0.1 in AA group) in hepatic tissues (p>0.05). Furthermore, it down-regulated Bax and caspase-3 expression in colonic and hepatic tissues upon comparison with AA group. Collectively, flavocoxid conferred a protective impact against acetic acid-induced colitis in rats via attenuating oxidative stress, inflammation, and apoptosis.
Show more [+] Less [-]Cadmium Tolerance Mechanism of Solanum nigrum Based on Subcellular Distribution and Organic Acid Content
2022
Hua, Li | Liang, Zhiyong | Wei, Ting
Solanum nigrum (S. nigrum), a newly discovered Cd-hyperaccumulator, has attracted the attention of many scholars. The present experiment was aimed to explore the difference of Cd accumulation ability among different S. nigrum genotypes and reveal the underlying mechanism. Three different genotypes of S. nigrum were grown in a hydroponic system with different Cd levels (0, 10,25, 50, 100 mg L⁻¹, respectively); the Cd content, subcellular distribution of Cd, net Cd fluxes of in S. nigrum roots, and organic acid content in S. nigrum leaves were investigated. The results showed that Cd was more abundant in cell sap and cell wall fraction than that in organelle fraction. The content of organic acids in three species of S. nigrum was citric acid > tartaric acid > acetic acid > malic acid > oxalic acid. Non-destructive micrometry (NMT) revealed that the net Cd fluxes of the same species of S. nigrum first increased and then decreased with increasing of Cd concentration. And among all tested genotypes, the net Cd fluxes were stronger in the genotype of S. nigrum (HZ).
Show more [+] Less [-]Anticolitic activity of prodigiosin loaded with selenium nanoparticles on acetic acid–induced colitis in rats
2022
Kassab, Rami B. | Elbaz, Mohamad | Oyouni, Atif A. A. | Mufti, Ahmad H. | Theyab, Abdulrahman | Al-Brakati, Ashraf | Mohamed, Hala A. | Hebishy, Ali M. S. | Elmallah, Mohammed I. Y. | Abdelfattah, Mohamed S. | Abdel Moneim, Ahmed E.
Ulcerative colitis (UC) is a chronic autoimmune inflammatory disease associated with extensive mucosal damage. Prodigiosins (PGs) are natural bacterial pigments with well-known antioxidant and immunosuppressive properties. In the current study, we examined the possible protective effect of PGs loaded with selenium nanoparticles (PGs-SeNPs) against acetic acid (AcOH)-induced UC in rats. Thirty-five rats were separated into five equal groups with seven animals/group: control, UC, PGs (300 mg/kg), sodium selenite (Na₂SeO₃, 2 mg/kg), PGs-SeNPs (0.5 mg/kg), and 5-aminosalicylates (5-ASA, 200 mg/kg). Interestingly, PGs-SeNPs administration lessened colon inflammation and mucosal damage as indicated by inhibiting inflammatory markers upon AcOH injection. Furthermore, PGs-SeNPs improved the colonic antioxidant capacity and prevented oxidative insults as evidenced by the upregulation of Nrf2- and its downstream antioxidants along with the decreased pro-oxidants [reactive oxygen species (ROS), carbonyl protein, malondialdehyde (MDA), inducible nitric oxide synthase (iNOS), and nitric oxide (NO] in the colon tissue. Furthermore, PGs-SeNPs protected intestinal cell loss through blockade apoptotic cascade by decreasing pro-apoptotic proteins [Bcl-2-associated X protein (Bax) and caspase-3] and increasing anti-apoptotic protein, B cell lymphoma 2 (Bcl2). Collectively, PGs-SeNPs could be used as an alternative anti-colitic option due to their strong anti-inflammatory, antioxidant, and anti-apoptotic activities.
Show more [+] Less [-]Isolation, biochemical characterization, and development of a biodegradable antimicrobial film from Cirrhinus mrigala scale collagen
2022
Collagen is a promising candidate for food and pharmaceutical applications due to its excellent biocompatibility, low antigenicity, and controlled biodegradability; however, its heavy price restricts its utilization. Fish scales generated during the processing are generally regarded as waste material and an environmental pollutant, though they are a promising source of collagen. In the present study, Cirrhinus mrigala scales were demineralized and extracted for acid-soluble collagen (ASC) using acetic acid, with a collagen yield of 2.7%. UV–Vis spectra, SDS-PAGE, FTIR analyses, and amino acid composition confirmed the type I nature of the collagen extracted. The denaturation temperature of the collagen was found to be 30.09 °C using differential scanning calorimetry (DSC). The collagen was highly soluble at acidic pH and lower NaCl concentrations while its solubility was lowered in alkaline conditions and NaCl concentrations above 0.5 M. The collagen exhibited good emulsifying potential with an emulsion activity index (EAI) and emulsion stability index (ESI) of 21.49 ± 0.22 m² g⁻¹ and 15.67 ± 0.13 min, respectively. Owing to the good physicochemical characteristics of the extracted collagen, collagen-chitosan-neem extract (CCN) films were prepared subsequently which showed good antimicrobial activity against Bacillus subtilis NCIM 2635, Staphylococcus aureus NCIM 2654, Escherichia coli NCIM 2832, and Pseudomonas aeruginosa NCIM 5032, suggesting the potential of collagen in the development of antimicrobial films. These results demonstrate that the collagen from fish waste could be valorized and used effectively along with chitosan and neem extract for the synthesis of novel biodegradable films with antimicrobial efficacy.
Show more [+] Less [-]Umbelliferone ameliorates ulcerative colitis induced by acetic acid via modulation of TLR4/NF-κB-p65/iNOS and SIRT1/PPARγ signaling pathways in rats
2022
Abdel-Wahab, Basel A. | Alkahtani, Saad A. | Alqahtani, Abdulsalam A. | Hassanein, Emad H. M.
Ulcerative colitis (UC) is a common chronic, idiopathic inflammatory bowel disease associated with inflammatory perturbation and oxidative stress. Umbelliferone (UMB) is a potent anti-inflammatory and antioxidant coumarin derivative. Depending on the possible mechanisms, we aimed to explore and elucidate the therapeutic potential of UMB on UC-inflammatory response and oxidative injury-induced via intrarectal administration of acetic acid (AA) in rats. Animals were assigned into four groups: control group, UMB (30 mg/kg, oral)-treated group, AA-induced colitis model group (2 ml of AA; 3% v/v), and colitis treated with UMB group. The results showed that UMB improved macroscopic and histological tissue injury caused by the AA. Mechanistically, UMB reduced the elevated colonic TNF-α, IL-6, MPO, and VCAM-1 and downregulated the gene and protein expression of TLR4, NF-κB, and iNOS signaling factors, exhibiting potent anti-inflammatory effects. Moreover, UMB upregulated the gene and protein expression of both SIRT1 and PPARγ signaling pathways, thereby inhibiting both oxidative injury and inflammatory response. Conclusively, UMB protected rats against AA-induced UC by suppressing the TLR4/NF-κB-p65/iNOS signaling pathway and promoting the SIRT1/PPARγ signaling. Our results showed the effectiveness of UMB in alleviating the pathogenesis of UC and introduced it as a possible therapeutic applicant for clinical application.
Show more [+] Less [-]