scholarly journals Removal of Various Hazardous Materials Using a Multifunctional Biomass-Derived Hydroxyapatite (HAP) Catalyst and Its Antibacterial Effects

Water ◽  
2021 ◽  
Vol 13 (22) ◽  
pp. 3302
Author(s):  
Sanha Jang ◽  
Kyeongmun Park ◽  
Sehwan Song ◽  
Haksoo Lee ◽  
Sungkyun Park ◽  
...  
Keyword(s):  
Removal Efficiency ◽  
Room Temperature ◽  
Hazardous Materials ◽  
Antibacterial Effects ◽  
E Coli ◽  
Phosphate Ion ◽  
High Metal ◽  
Acidic Conditions ◽  
Ph Conditions ◽  
Maximum Removal

In the present study, oyster shells, a cause of environmental pollution, were employed effectively to synthesize hydroxyapatite (HAP) by facile oxidation and phosphorylation. The ability of HAP to adsorb various metal cations and inhibit bacterial growth was validated. The biomass-derived HAP catalyst exhibited high metal cation adsorption in water at room temperature and under various acidic conditions (M = Cr, Mn, Ni, Cu, Cd, Ba, and Pb). HAP was demonstrated to have a maximum removal efficiency of 92.8% for the heavy metal Pb. Even under different pH conditions, HAP was demonstrated to be effective for the removal of three harmful heavy metals, Cr, Cd, and Pb, with a particularly high removal efficiency demonstrated for Pb under all conditions (average removal efficiency of Cr: 63.0%, Cd: 59.9%, and Pb: 91.6%). In addition, HAP had a significant influence on phosphate ion adsorption in aqueous solution, eliminating 98.1% after 3 min. Furthermore, biomass-derived HAP was demonstrated to have significant antibacterial activity against E. coli and S. aureus (5 mM: 74% and 78.1%, 10 mM: 89.6% and 96.0%, respectively).

Removal of methylene blue from water by γ-MnO2

2011 ◽  
Vol 64 (4) ◽  
pp. 899-903 ◽  
Author(s):  
W. H. Kuan ◽  
C. Y. Chen ◽  
C. Y. Hu
Keyword(s):  
Methylene Blue ◽  
Organic Carbon ◽  
Room Temperature ◽  
Oxidative Degradation ◽  
Dramatic Decrease ◽  
Dimethylamino Group ◽  
X Ray ◽  
Toc Removal ◽  
Acidic Conditions ◽  
Ph Conditions

Methylene blue (MB) is a cationic dyestuff, which is particularly resistant to biodegradation. The molecular sieved γ-MnO2 was used as an adsorbent/oxidant to remove the MB at room temperature and in visible light. The removal efficiency was mainly evaluated by X-ray diffractometer (XRD), UV–Vis spectrometer (UV–Vis), total organic carbon (TOC). The results revealed that the mechanisms of MB removal by γ-MnO2 are significantly influenced by the pH. In acidic conditions, hypsochromic effects (i.e. blue shifts of UV–Vis spectra) resulting from N-demethylation of the dimethylamino group in MB may occur concomitantly with oxidative degradation by γ-MnO2. However, the TOC in solution after γ-MnO2 treatment in acidic conditions did not show a dramatic decrease. At near neutral pH conditions, there was almost no UV–Vis absorption for the MB solution, however, only 50% TOC removal was observed. It indicated that MB was not only adsorbed onto γ-MnO2 but also partially oxidatively degraded to other organic compounds which were colourless for UV–Vis.

scholarly journals Bisphenol A degradation by a new acidic nano zero-valent iron diatomite composite

2016 ◽  
Vol 6 (15) ◽  
pp. 6066-6075 ◽  
Author(s):  
Lingya Ma ◽  
Hongping He ◽  
Runliang Zhu ◽  
Jianxi Zhu ◽  
Ian D. R. Mackinnon ◽  
...  
Keyword(s):  
Bisphenol A ◽  
Removal Efficiency ◽  
Zero Valent Iron ◽  
Nano Zero Valent Iron ◽  
Acidic Conditions ◽  
Ph Conditions ◽  
Iron Material

A new nano zero-valent iron material that generates acidic conditionsin situexhibits a high removal efficiency of BPA under natural pH conditions.

Adsorption and Catalysis of Orange II from Wastewater by Inorganic-Organic-Bentonite

2011 ◽  
Vol 340 ◽  
pp. 236-240
Author(s):  
Jian Feng Ma ◽  
Jian Ming Yu ◽  
Bing Ying Cui ◽  
Ding Long Li ◽  
Juan Dai
Keyword(s):  
Adsorption Capacity ◽  
Removal Efficiency ◽  
Dye Removal ◽  
Maximum Adsorption Capacity ◽  
Orange Ii ◽  
Acid Dye ◽  
Secondary Pollution ◽  
Organic Bentonite ◽  
Maximum Removal

Inorganic-organic-bentonite was synthesized by modification of bentonite by Hydroxy-iron and surfactant, which could be applied in dye removal by adsorption and catalysis. The removal of acid dye Orange II was studied at various factors such as time and pH of solution. The results showed that the inorganic-organic-bentonite could efficiently remove the dye with efficiency of 96.22%. The maximum adsorption capacity is 76 mg/g. The pH of solution has significant effect on both adsorption and catalysis. When pH was 4, the maximum removal efficiency of adsorption and catalysis were 97.57% and 87.23%, respectively. After degradation, the secondary pollution was diminished and the bentonite could be reused.

scholarly journals Synthesis, antibiotic structure–activity relationships, and cellulose dissolution studies of new room-temperature ionic liquids derived from lignin

2021 ◽  
Vol 14 (1) ◽  
Author(s):  
Shihong Liu ◽  
Michael Gonzalez ◽  
Celine Kong ◽  
Scott Weir ◽  
Aaron M. Socha
Keyword(s):  
Antibacterial Activity ◽  
Ionic Liquids ◽  
Room Temperature ◽  
Oxidation Products ◽  
Cellulose Dissolution ◽  
Melting Points ◽  
E Coli ◽  
Alkyl Chains ◽  
Renewable Feedstocks ◽  
Commodity Chemicals

Abstract Background Ionic liquids (ILs) are promising pretreatment solvents for lignocellulosic biomass, but are largely prepared from petroleum precursors. Benzaldehydes from depolymerized lignin, such as vanillin, syringaldehyde, and 4-methoxy benzaldehyde, represent renewable feedstocks for the synthesis of ionic liquids. We herein report syntheses of novel lignin-derived ionic liquids, with extended N-alkyl chains, and examine their melting points, cellulose dissolution capacities, and toxicity profiles against Daphnia magna and E. coli strain 1A1. The latter organism has been engineered to produce isoprenol, a drop-in biofuel and precursor for commodity chemicals. Results The new N,N-diethyl and N,N-dipropyl methyl benzylammonium ILs were liquids at room temperature, showing 75–100 °C decreased melting points as compared to their N,N,N-trimethyl benzylammonium analog. Extension of N-alkyl chains also increased antibacterial activity threefold, while ionic liquids prepared from vanillin showed 2- to 4-fold lower toxicity as compared to those prepared from syringaldehyde and 4-methoxybenzaldehyde. The trend of antibacterial activity for anions of lignin-derived ILs was found to be methanesulfonate < acetate < hydroxide. Microcrystalline cellulose dissolution, from 2 to 4 wt% after 20 min at 100 °C, was observed in all new ILs using light microscopy and IR spectroscopy. Conclusions Ionic liquids prepared from H-, S- and G-lignin oxidation products provided differential cytotoxic activity against E. coli and D. magna, suggesting these compounds could be tailored for application specificity within a biorefinery.

scholarly journals Flavone-Rich Fractions and Extracts from Oroxylum indicum and Their Antibacterial Activities against Clinically Isolated Zoonotic Bacteria and Free Radical Scavenging Effects

Molecules ◽  
2021 ◽  
Vol 26 (6) ◽  
pp. 1773
Author(s):  
Patchima Sithisarn ◽  
Piyanuch Rojsanga ◽  
Pongtip Sithisarn
Keyword(s):  
Antibacterial Activities ◽  
Inhibitory Effect ◽  
Total Flavonoid ◽  
Total Phenolic ◽  
Antibacterial Effects ◽  
E Coli ◽  
Young Fruit ◽  
Oroxylum Indicum ◽  
Zoonotic Bacteria

Oroxylum indicum extracts from the seeds collected from Lampang and Pattani provinces in Thailand, and young fruits and flowers exhibited in vitro display antioxidant and antibacterial activities against clinically isolated zoonotic bacteria including Staphylococcus intermedius, Streptococcus suis, Pseudomonas aeruginosa, β-hemolytic Escherichia coli and Staphylococcus aureus. The orange crystals and yellow precipitates were obtained from the preparation processes of the seed extracts. The orange-red crystals from the seeds collected from Lampang province exhibited strong in vitro 2,2-diphenyl-1-picrylhydrazyl (DPPH) scavenging effects (EC50 value = 25.99 ± 3.30 μg/mL) and antibacterial effects on S. intermedius and β-hemolytic E. coli while the yellow precipitate from the same source exhibited only antioxidant activity. Quantitative analysis of phytochemicals in O. indicum samples by spectrophotometric and HPLC techniques showed that they contained different amounts of total phenolic, total flavonoid and three major flavones; baicalin, baicalein and chrysin contents. Young fruit extract, which contained low amounts of flavone contents, still promoted antibacterial effects against the tested bacteria with IC50 values lower than 1 mg/mL and MIC values between 4 to 10 mg/mL in S. intermedius, S. aureus and S suis while higher IC50 and MIC values against P. aeruginosa and β-hemolytic E. coli were found. From scanning electron microscopy, the extract of the young fruit of O. indicum promoted morphological changes in the bacterial cells by disrupting the bacterial cell walls, inducing leakage of the cellular content, and generating the abnormal accumulation of cells. The mechanism of action of the extract for this antibacterial effect may be the disruption of the cell membrane and abnormal cell aggregations. Regression analysis of the results suggests the correlation between total phenolic and total flavonoid contents and antioxidant and antibacterial effects. Baicalin was found to have a high correlation with an inhibitory effect against β-hemolytic E. coli while three unidentified peaks, which could be flavones, showed high correlations with an inhibitory effect against S. intermedius, S. suis, P. aeruginosa and S. aureus.

Evaluation of α-glucosidase inhibition, antioxidant and antibacterial effects of Gymnema sylvestre R. Br.

2021 ◽  
Vol 50 (1) ◽  
pp. 61-68
Author(s):  
Tahseen Ghous ◽  
Kalsoom Akhtar ◽  
Saiqa Andleeb ◽  
Saira Khizar ◽  
Shaukat Ali ◽  
...  
Keyword(s):  
Total Iron ◽  
Gymnema Sylvestre ◽  
Aqueous Extracts ◽  
Inhibition Assay ◽  
Antibacterial Effects ◽  
Leaf Extracts ◽  
E Coli ◽  
Maximum Inhibition ◽  
Ic50 Value ◽  
Phytochemical Constituents

The results of antioxidant assays with Gymnema sylvestre leaf extracts revealed that methanol, acetone, and aqueous extracts possessed maximum DPPH (83, 83, and 75%) and ABTS scavenging potential (85, 71, and 82%). Chloroform possessed maximum total flavonoid (24.6 mg/100 ml) and total iron contents (435.3 ± 0.0125 mg FeSO4 E/G). The extracts of n-hexane, ethyl acetate, and chloroform of Gymnema sylvestre leaves displayed an IC50 value of 170.2, 44.4, 131.6 μg/ml, respectively in α-glucosidase inhibition assay. Methanol and aqueous extracts showed maximum inhibition of E. ammni (17 ± 2.0 and 19.6 ± 0.57 mm), E. coli (15.3 ± 0.57 and 17.6 ± 0.57 mm), and S. aureus (16.6 ± 1.52 and 19.3 ± 1.15 mm). It may be concluded that all potential effects of G. sylvestre leaf extracts were due to the presence of phytochemical constituents such as flavonoids, steroids, quinones, phenols, triterpenoids, tannins, alkaloids, and saponins. Present findings suggest that these extracts present a satisfactory source for the preparation of antioxidant and antidiabetic medicines.

Characteristics of Packaged Water under Different Storage Conditions Within Osogbo Metropolis

2020 ◽  
Vol 2 (2) ◽  
Author(s):  
O.O Fadipe
Keyword(s):  
Room Temperature ◽  
Control Unit ◽  
Storage Conditions ◽  
Prolonged Storage ◽  
E Coli ◽  
Physico Chemical ◽  
Routine Basis ◽  
Regulatory Bodies ◽  
Microbiological Analyses ◽  
Sachet Water

The study investigated the characteristics of packaged water stored under ambient and sunlight conditions. This is with a view to testing the effect of prolonged storage under different storage conditions on its quality. In addition it analyzed the interactions between the parameters. Two packs each of bottled and sachet water was purchased from each factory at the point of production and ready for distribution to wholesalers. Twenty eight pieces of packaged water from each factory were kept at room temperature and the same quantity were kept under sunlight. Physico-chemical and microbiological analyses were carried out on the remaining packaged water within 24hrs. Half of the samples stored at the two storage conditions were removed for analysis at 3 weeks while the remaining half was analyzed after 6weeks. The physico-chemical characteristics were within the WHO recommended values except for the pH of some samples that have values in the acidic range of 6.2-6.48. All the physico-chemical values increased for samples kept under sunlight. All the water samples showed growth in faecal coliform (4-46 cfu/100 mL) and E. coli (0-13 cfu/100 mL) for samples kept under sunlight at three weeks and this growth increased to the sixth week. The presence of E. coli is an indication that the packaged water is not pure. Displaying packaged water under the sunlight and storing beyond 3 weeks by vendors have effect on the potability of the product. The regulatory bodies should raise awareness and ensure manufacturer have a quality control unit to test on a routine basis.

Study on the mutual interactions between the parameters of a CANON system and its coping strategy when operating at room temperature (15 to 25 °C) using response surface methodology

2014 ◽  
Vol 69 (9) ◽  
pp. 1805-1812 ◽  
Author(s):  
Jian Zhou ◽  
Guangxu Qin ◽  
Jianbing Zhang ◽  
Yancheng Li ◽  
Qiang He ◽  
...  
Keyword(s):  
Response Surface Methodology ◽  
Response Surface ◽  
Removal Efficiency ◽  
Coping Strategy ◽  
Room Temperature ◽  
Loading Rate ◽  
Nitrogen Loading ◽  
Independent Variables ◽  
Do Concentration ◽  
N Loading

The coping strategy of a CANON (completely autotrophic nitrogen removal over nitrite) reactor working at room temperature was investigated using response surface methodology. The total nitrogen (TN) removal efficiency was taken as a dependent variable. The temperature (X), dissolved oxygen (DO) concentration (Y), and influent nitrogen loading rate (Z) were taken as independent variables. Results showed that the relation of these three independent variables can be described by the TN removal efficiency expressed as −5.03 + 1.51X + 45.16Y + 30.13Z + 0.26XY + 1.84XZ − 0.04X2 − 9.06Y2 − 99.00Z2. The analysis of variance proved that the equation is applicable. The response surface demonstrated that the temperature significantly interacts with the DO concentration and influent N loading rate. A coping strategy for the CANON reactor working at room temperature is thus proposed: altering the DO concentration and the N loading rate to counterbalance the impact of low temperature. The verification test proved the strategy is viable. The TN removal efficiency was 91.3% when the reactor was operated under a temperature of 35.0 °C, a DO of 3.0 mg/L, and a N loading rate of 0.70 kgN/(m³ d). When the temperature dropped from 35.0 to 19.2 °C, the TN removal efficiency was kept at 88.7% by regulating the influent N loading rate from 0.7 kgN/(m³ d) to 0.35 kgN/(m³ d) and the DO concentration from 3.0 to 2.6 mg/L.

Influence of Inoculation Method, Spot Inoculation Site, and Inoculation Size on the Efficacy of Acidic Electrolyzed Water against Pathogens on Lettuce

2003 ◽  
Vol 66 (11) ◽  
pp. 2010-2016 ◽  
Author(s):  
SHIGENOBU KOSEKI ◽  
KYOICHIRO YOSHIDA ◽  
YOSHINORI KAMITANI ◽  
KAZUHIKO ITOH
Keyword(s):  
Population Size ◽  
Room Temperature ◽  
Escherichia Coli O157 ◽  
Bacterial Inoculation ◽  
Pathogen Population ◽  
Salmonella Spp ◽  
Electrolyzed Water ◽  
Inoculation Methods ◽  
E Coli ◽  
Inoculation Site

The influence of bacterial inoculation methods on the efficacy of sanitizers against pathogens was examined. Dip and spot inoculation methods were employed in this study to evaluate the effectiveness of acidic electrolyzed water (AcEW) and chlorinated water (200 ppm free available chlorine) against Escherichia coli O157:H7 and Salmonella spp. Ten pieces of lettuce leaf (5 by 5 cm) were inoculated by each method then immersed in 1.5 liters of AcEW, chlorinated water, or sterile distilled water for 1 min with agitation (150 rpm) at room temperature. The outer (abaxial) and inner (adaxial) surfaces of the lettuce leaf were distinguished in the spot inoculation. Initial inoculated pathogen population was in the range 7.3 to 7.8 log CFU/g. Treatment with AcEW and chlorinated water resulted in a 1 log CFU/g or less reduction of E. coli O157:H7 and Salmonella populations inoculated with the dip method. Spot inoculation of the inner surface of the lettuce leaf with AcEW and chlorinated water reduced the number of E. coli O157:H7 and Salmonella by approximately 2.7 and 2.5 log CFU/g, respectively. Spot inoculation of the outer surface of the lettuce leaf with both sanitizers resulted in approximately 4.6 and 4.4 log CFU/g reductions of E. coli O157:H7 and Salmonella, respectively. The influence of inoculation population size was also examined. Each sanitizer could not completely eliminate the pathogens when E. coli O157:H7 and Salmonella cells inoculated on the lettuce were of low population size (103 to 104 CFU/g), regardless of the inoculation technique.

Validation of Time and Temperature Values as Critical Limits for the Control of Escherichia coli O157:H7 during the Production of Fresh Ground Beef

2006 ◽  
Vol 69 (8) ◽  
pp. 1978-1982 ◽  
Author(s):  
J. E. MANN ◽  
M. M. BRASHEARS
Keyword(s):  
Escherichia Coli ◽  
Room Temperature ◽  
Hazard Analysis ◽  
Control Point ◽  
Ground Beef ◽  
Escherichia Coli O157 ◽  
Meat Processing ◽  
E Coli ◽  
Critical Control Point ◽  
Critical Limits

In order to provide beef processors with valuable data to validate critical limits set for temperature during grinding, a study was conducted to determine Escherichia coli O157:H7 growth at various temperatures in raw ground beef. Fresh ground beef samples were inoculated with a cocktail mixture of streptomycin-resistant E. coli O157:H7 to facilitate recovery in the presence of background flora. Samples were held at 4.4, 7.2, and 10°C, and at room temperature (22.2 to 23.3°C) to mimic typical processing and holding temperatures observed in meat processing environments. E. coli O157:H7 counts were determined by direct plating onto tryptic soy agar with streptomycin (1,000 μg/ml), at 2-h intervals over 12 h for samples held at room temperature. Samples held under refrigeration temperatures were sampled at 4, 8, 12, 24, 48, and 72 h. Less than one log of E. coli O157:H7 growth was observed at 48 h for samples held at 10°C. Samples held at 4.4 and 7.2°C showed less than one log of E. coli O157:H7 growth at 72 h. Samples held at room temperature showed no significant increase in E. coli O157:H7 counts for the first 6 h, but increased significantly afterwards. These results illustrate that meat processors can utilize a variety of time and temperature combinations as critical limits in their hazard analysis critical control point plans to minimize E. coli O157:H7 growth during the production and storage of ground beef.

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