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Kinetics and Mechanism of Ammonium Ion Adsorption Using Natural Zeolite - Mordenite
Full text linkMordenite, one of the natural zeolites , has the capacity to remove
ammonium ion from wastewaters through adsorption phenomenon. This study is a
preliminary work of using mordenite to remove ammonium in effluent for tertiary
treatment. The feasibility of using mordenite to remove ammonium ion in
aqueous solution was carried out using shake flask, stirred tank batch reactor and
packed-bed column experiments. The effect of mordenite particle size,
ammonium concentration, mordenite concentration, pH, temperature and degree
of agitation on the efficiency of adsorption were investigated. The kinetics of
ammonium ion sorption was determined using Langmuir and Scatchard sorption
isotherm models. The mechanism of ammonium adsorption was investigated
using FTIR and electron microscope.
In shake flask experiment under equilibrium conditions, the efficiency of
ammonium ion removal was optimum at resident time of 6 hours, for granules of 75 µm size, in water containing less than 6 mg/L ammonium ion, in mordenite
concentration of 3 g/L, at room temperature, with agitation of 200 rpm and near
neutral initial pH (6.5-7.5). Ammonium ion removal of 94% (2.49 mg/g uptake)
was achieved when 50 g/L mordenite was used to remove 100 mg/L ammonium
concentration under optimum conditions. The sorption isotherm kinetic data of
ammonium ion by mordenite fitted well to Langmuir model but did not fit well to
Scatchard plot. SEM and FTIR data indicated that ammonium ion was adsorbed
on the mordenite particle. When 2 L stirred tank: reactor was used as a contactor,
the ammonium uptake capacity ranging from 85-96% was obtained at agitation
speed of 200 rpm, concentration of mordenite of 2.67 g/L and 6 mg/L ammonium
concentration. Absolute removal of ammonium from solution was achieved when
fixed packed-bed column was used as a contactor at low flowrate (2 mL/min) and
increased weight of mordenite in the column (48 g), which show less than 5 mg/L
ammonium in the effluent before breakthrough was achieved when 100 mg/L
ammonium concentration was used . Desorption experiments showed that 37%
ammonium recovery in the shake flask and 80-98% in the column contactor.
From the study, the result indicated that mordenite has a potential to be promoted
as adsorbent that could be used to removed ammonium from solution and can be
apply for wastewater treatment
Isolation, Identification and Antioxidative Activity Of Phenolics in Palm Oil Mill Effluent
Full text linkThe objectives of the study are to isolate, and identifl the phenolic compounds present in
the palm oil mill effluent (POME) and evaluate their antioxidative activity. Combinations
of column and partition chromatography were used in the isolation of the phenolic
compounds. Antioxidative activities of the POME hctions were evaluated for fke
radical scavenging activity, lipid thiocyanate, &carotene-linoleate and reducing assays.
Identification of the phenolic compounds in POME filtrate was carried out using high
performance liquid chromatography (HPLC), followed by confirmation of the
compounds using gas chromatography mass spectrometry (GCIMS) and liquid
chromatography mass spectrometry (LCIMS). The study revealed the presence of
cinnamic acid derivatives, which were measured at 320 nm. These included chlorogenic,
p-cournaric, caffeic, ferulic acids and rutin hydrate. Benzoic acid derivatives, which were
identified as protocatechuic, gentisic, p-hydroxybenzoic and vanillic acids were also
present when measured at 260 nrn. Hydrolysis of the sample did not affect the chromatographic pattern obtained indicating the stability of the phenolic compounds in
the POME filtrate. Flavan-3-01 groups (catechins) were identified from ytterbium
precipitation method. Four fractions have been isolated from POME filtrate based on
flash chromatography coupled with uv/vis detection. The antioxidative activity of each
h t i o n was then evaluated. All the POME fractions demonstrated excellent antioxidative
activity in all the assays used. This is especially true for both Fractions 3 and 4. Fraction
1 exhibited highest antioxidative activity based on reducing assay followed by Fraction 3
indicating the excellent metal chelating ability of the phenolics in these hctions. The
POME fractions were found to contain different levels of total phenolics, which did not
necessarily correspond to the strength of antioxidative activity, measured for each
hction. Fraction 3 showed strong free radical scavenger and phenolic content was also
high. Fraction 2 showed low antioxidant activity, while total phenolic content was low.
However, Fraction 4 showed high antioxidant activity with low total phenolic content.
This indicates the presence of different phenolic compounds in the different hctions.
Results showed that Fraction 1 contained an unknown polar compound and
protocatechuic acid with strong metal chelating activity, Fraction 2 was rich in phydroxybenzoic
acid, Fraction 3 contained three unknown cinnamic acid derivatives and
Fraction 4 contained known cinnamic acid derivatives compounds including p-coumaric
acid, rutin hydrate and ferulic acid with lower polarity. The cinnamics in Fraction 3
consistently exhibited higher antioxidative properties compared with benzoics in Fraction
2. Combination study of the fractions revealed that mixture of Fraction 3 and ascorbic
acid had better hx radical scavenging activity. However, the synergistic effect was
observed only at low concentration of 2.5 and 5 mgll of Fraction 3 and ascorbic acid. The individual compounds of Fraction 3 (cimamic acid derivatives) including Compounds
14, 15 and 16 exhibited the highest ike radical scavenging activity. Highest antioxidative
activity was also measured when Compounds 15 and 16 were combined (double
combined) while for triple combinations, the highest activity was seen with Compounds
13, 14, and 15 at 15 mgA of total phenolic contents. The results showed that there was a
synergistic effect between the compounds in particular those in Fraction 3. GCMS and
LC/MS were employed to confirm identifj of unknown compounds in Fraction 3. Three
compounds in Fraction 3 were observed to exhibit similar absorbance spectra using
HPLC with diode array detection. LC/MS revealed presence of dimer with maximum
molecular weight of 335 dz. GCMS revealed the presence of compounds with a general
cinnamic acid structure and derivatives with silylate group. Antioxidative activity of the
compounds was in the following order, Compound 14 > Compound 16 > Compound 15.
Compounds 14, 15 and 16 were tentatively identified as 2,4dihydroxycimamic acid, 2,sdihydroxycinnarnic
acid and 2,3dihydroxycinnamic acid
Bio-organic fungicide of Catharanthus roseus stems extract inhibit the growth of Fusarium oxysporumon Capsicum annum seedling
Full text linkFusarium oxysporum is a well-known fungus that causes a major commercial plant disease in the world. Due to the issue, the antifungal activity of Catharanthus roseus stems extract as bio-organic fungicide against F. oxysporumon Capsicum annum seedling was studied. The spore suspensions of F.oxysporum and C. roseusstems extract were prepared to study the minimum inhibitory concentration (MIC) and minimum fungicidal concentration (MFC) tests in the laboratory. The application of C. roseus stems extract at the concentrations of 100, 500, 1,000, 1,500 and 2,000 µg/mL against F. oxysporum were included in the in-vitro study. For in-vivo test, F. oxysporum on C. annum seedlings were applied with the plant extract at concentrations of 1,000, 1,500 and 2,000 µg/mL in greenhouse study. The result showed that the extractwith2,000 µg/mL has higher significant difference (p<0.05) inhibited the growth of F. oxysporum plant fungal compared to other concentrations of MIC tested. The MFC test indicated that day nine was
proven to have high negative impact of the fungal than day six. In in-vivo study, the antifungal activity showed 100% effect of disease injury for the growth of C. annum plant species in green house. The result also showed that the concentration of C. roseus stems extract at 2,000 µg/mL has significantly higher (p<0.05) activity against F. oxysporum on the seedlings compared to other concentrations. Thus, the
study indicated that C. roseus stems extract has novelty of bio-organic compounds that contribute to the development of new antifungal agents to protect crop plants from fungal disease which also safe to environmental ecology compared to other commercial chemical fungicide which is highly used nowadays
The effect on phenolic content and antioxidant capacity Of selected medicinal plant planted on contaminated soil
Full text linkEvaluation of antioxidative activity of henolics in blue green algae of methanolic extracts
Full text linkOne of the factors that affect climate change is high carbon dioxide (CO2) gas in the atmosphere. Algae needs CO2, sunlight and water for their growth and can be cultivated in open ponds. Algae have varying proportions of proteins, carbohydrates, fats and antioxidants, which can be used as diet supplements. Phenolics have been shown to exhibit bioactive properties, particular antioxidant effects. A phenolic rich extract has been isolated from the algae species, Arthrospira platensis. The objectives of this study were to determine the total amount of phenolics extracted from methanolic solvent of blue green algae and to evaluate antioxidative activity of phenolic extracts in different concentrations of methanolic solvent using free radical scavenging assay. This study began with extraction of the Arthrospira with liquid nitrogen into powder after filtration and overnight drying in the oven. This is followed by determination of total phenolics in different concentrations of methanolic solvent and studied for free radical scavenging activity using DPPH assay. The concentrations of total phenolics determined by the folin-ciocalteu method was found to be 252.72 mg/L GAE in aqueous extracts which showed that phenolic compounds can dissolve more in water medium. The radical scavenging activity of the extracts determined using 2, 2 diphenyl-picrylhydrazyl radical (DPPH) as free radical indicated that phenolics in methanolic extracts exhibit hydrogen donating capacity. The 100% methanolic extracts showed significantly higher antioxidative activities in all assays while in different concentrations of 100% methanolic extracts, the concentration of 120 mg/L showed the highest free radical scavenging activity. The high scavenging activity of Arthrospira platensis may be due to hydroxyl groups existing in the chemical structure of phenolic compounds that can provide the necessary component as a radical scavenger. This study showed that blue-green algae is rich in phenolic compounds which are natural antioxidants and may help reduce the problem of climate change by absorption of CO2 from the atmosphere
The effect of heavy metals on biodegradation of carbofuran by microbial strain enriched from Agricultural areas
No full textThe effect of heavy metals on the degradation of carbofuran by immobilzed bacterial cell was checked by culturing in the MSM medium at 37oC in the presence of 0-1 mg/L of heavy metals. Bioremediation systems represent a biologically sustainable means to degrading organic pollutants such as carbofuran insecticide, with little energy demand and operational expenses in addition to high efficiency and substrate specificity. Nonetheless, heavy metals present in the agricultural lands may thwart the process efficiency by poisoning carbofuran-degrading microbial isolates. Here, we experimentally tested the tolerance of carbofuran-degrading immobilized bacterial isolated from vegetable plantation area for mercury (Hg) and copper (Cu). The of the tested metals inhibited carbofuran biodegradation to different extents, depending on concentration. At pH of 7.0 and 37°C, complete inhibition of carbofuran biodegradation by Hg occurred 0.4, 0.5, 0.6 and 0.7 mg/L, respectively. Lower concentrations of these metals decreased the rate of carbofuran− biodegradation, with relatively long lag times. Interestingly, the immobilize isolate tolerated higher concentrations, although both the rate and extent of carbofuran− biodegradation were affected
Quantification of total phenolics in different parts of Pluchea indica (Less) ethanolic and water extracts
Full text linkOne of the compounds present in Pluchea indica extracts is antioxidant which plays an important role in inhibiting free radicals and thus protects humans against infections and degenerative diseases, such as cancer, arthritis, and ageing process. The main objective of this study was to investigate and determine the total phenolic compounds of Pluchea indica in different concentrations of ethanolic extracts. This species was chosen because of its high phytonutrient compounds with potential medicinal properties. There was a significant difference (P ≤ 0.05) in the total phenolic among the different parts of the tested plant. 50% of the ethanolic extract produced the highest total phenolic compounds (1775.00±86.00 to 658.95±5.00 µmol/g), followed by water extract (759.79±1.53 µmol/g) and 100% ethanol extract (352.72±22.30 to 249.29±5.37 µmol/g), respectively. In terms of the plant parts, the leaves contained the highest phenolic compounds (1775.00±86.00 µmol/g in 50% ethanol extract, 759.79±1.53 µmol/g in 100% aqueous extract and 352.72±22.30 µmol/g in 100% ethanol extract), followed by the stems (990.22±24.00 µmol/g in 50% ethanol extract, 990.22±24.59 µmol/g in 100% aqueous extract and 293.48±0.00 µmol/g in 100% ethanol extract). Meanwhile, lower total phenolic compounds were detected in the flowers (727.71±11.00 µmol/g in 50% ethanol extract, 603.81±8.46 µmol/g in 100% aqueous extract and 249.29±5.37 µmol/g in 100% ethanol extract) and roots (658.95±5.00 µmol/g in 50% ethanol extract, 450.00±10.76 µmol/g in 100% aqueous extract and 272.28±0.53 µmol/g in 100% ethanol extract). Based on these findings, Pluchea indica has potential medicinal properties that can be further developed to produce neutraceutical products, diet supplements or cosmetic products. However, further research should first be conducted on the effects of these compounds on laboratory animals
Copper removal using Ochrobactrum specie isolated from contaminated wastewater
No full textBacterial and metal removal have received considerable attention recently, due to the potential use of microorganisms for treatment of contaminated wastewater. Removal and recovery of heavy metal ions from polluted wastewaters has appeared to be the potential alternative method for conventional treatment of contaminated wastewater. The purpose of the present work was to study the removal capacity of toxic metal from contaminated wastewater by using ochrobactrum sp. isolated from contaminated wastewater using different pH and temperature. Bacteria species have a high surface area to volume ratio, due to their small size and thus, they can offer a large contact interface that would interact with metals ion. The results indicated that bacterial isolate Ochrobactrum sp. is a suitable biosorbent for the removal of Cu (II) ion from metal polluted wastewater and might be applicable to the development of possibly cheap biosorbent for removing and recovering copper from effluents
Microorganisms and biosorption of heavy metals in the environment: a review paper
Full text linkIndustrial waste water and sediment containing heavy metals causes many ecological and health related problems. Many conventional methods were already being used to decontaminate the environment from adverse effect of these pollutants but yet most of the methods used are very expensive and far away from their best possible performance. The capability of microorganisms to bind metal ions is a well-known trend. Different experimental data are documented and presented for different metals and biomass types. In this review a brief overview of the potential of biosorbents and biosorption processes were critically reviewed. This briefly describes biosorption process and some of the analysis of different low-cost biosorbents used for heavy metal remediation from waste stream
Efficiency of CBM (complex beneficial microbes) to reduce river pollution of Malacca River
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