Removal of potentially toxic metal by biochar derived from rendered solid residue with high content of protein and bone tissue.

The purpose of this study was to produce rendering animal carcass residue char (RACR-C) by pyrolyzing the solid residues of low-recyclable rendered pig carcasses and to evaluate their cadmium (Cd) adsorption characteristics and mechanisms. As the pyrolysis temperature increased, the inorganic content of RACR-C increased, while the carbon content decreased. In particular, the surface structure and chemistry of RACR-Cs prepared at different pyrolysis temperatures were well described by SEM-EDS, XRD, XRF, TGA, and FTIR. The Cd adsorption characteristics of RACR-C were in good agreement with the Langmuir isotherm and pseudo-second-order models, and the Cd adsorption capacities of RACR-Cs prepared at various pyrolysis temperatures were in the order of RACR-C500 (73.5 mg/g)> RACR-C600 (53.8 mg/g)> RACR-C400 (41.5 mg/g) " RACR-C250 (15.9 mg/g). The intraparticle diffusion model suggested that the adsorption of Cd by RACR-C is greatly influenced by internal diffusion as well as external boundary. Since the Cd adsorption capacity of RACR-C is greatly influenced by the initial dosage, pH, and co-existing metals, it is necessary to manage these influencing factors when treating wastewater containing heavy metals. Our results suggest that Cd adsorption by RACR-C is a complex adsorption phenomenon by various mechanisms such as adsorption by functional group (CË­C and C-O), precipitation of Cd-P and ion exchange reaction by exchangeable cation occurring rather than by a single specific mechanism.

Effect of soil organic matter on the plant uptake of perfluorooctanoic acid (PFOA) and perfluorooctanesulphonic acid (PFOS) in lettuce on granular activated carbon-applied soil.

The presence of perfluorooctanoic acid (PFOA) and perfluorooctanesulphonic acid (PFOS) in crops is an important consideration for food safety. The soil organic matter (SOM) content may affect the adsorption potential of PFOA and PFOS in water and soil and their subsequent uptake in crops. To better understand these dynamics, the adsorption and uptake of PFOA and PFOS in lettuce were investigated using granular activated carbon (GAC)-treated soils with varying SOM content. The adsorption potential of GAC was investigated, with maximum adsorption capacities for PFOA and PFOS calculated to be 9.091 mg g-1 and 27.778 mg g-1, respectively. These values decreased to 5.208 mg g-1 and 17.241 mg g-1, respectively, after the addition of 0.04 wt% humic acid. The average plant uptake factor (PUF) in low and high perfluoroalkyl and polyfluoroalkyl acid (PFAA)-contaminated soils with 4.0 wt% SOM was restricted to 0.353 for PFOA and 0.108 for PFOS. The PUFs were approximately two times lower than those for soil with 2.6 wt% SOM. Addition of 1 wt% GAC to the soil successfully reduced the PUF by up to 99.4%, with values of 0.006 (PFOA) and 0.005 (PFOS) in 2.6 wt% SOM-treated soil and 0.079 (PFOA) and 0.023 (PFOS) in 4.0 wt% SOM-treated soil. Although the PUF in the GAC-treated soil was drastically decreased, the PUF of the soil with 4.0 wt% SOM was at least four times higher than that with 2.6 wt% SOM. Therefore, SOM content is an important consideration in the remediation of PFOA- and PFOS-contaminated farmland soil using carbonaceous adsorbent.

Utilization of liquid pig manure for resource cycling agriculture in rice-green manure crop rotation in South Korea.

A 2-year field experiment was carried out on rice (Oryza sativa, Japonica type) cultivation in South Korea. The objective of this study was to investigate the effect of application of liquid pig manure on biomass production and nutrient supply of green barley (Hordeum vulgare L.) and hairy vetch (Vicia villosa Roth) green manure crops and to evaluate the effect of nutrients supplied from these sources on rice yield and soil quality in a rice-green manure crop rotation system. Over the 2-year study period, application of liquid pig manure increased biomass production of green manure crops of barley and hairy vetch by more than 216% and 135%, respectively, compared with without liquid pig manure. Moreover, the results showed that the application of liquid pig manure significantly increased the nutrient supply levels in green barley- and hairy vetch-treated areas. Positive effects related to nutrient supply in green barley and hairy vetch treated with liquid pig manure were observed on rice yield, soil chemical characteristics, and microbial biomass C and N contents. In conclusion, the addition of liquid pig manure systems using green manure crops of green barley and hairy vetch improved rice productivity and soil quality. It is suggested that these combinations can be effective in developing resource cycling agriculture in a rice-green manure crop rotation system as it reduces the need for inorganic fertilizer.

Lead sorption characteristics of various chicken bone part-derived chars.

Recycling food waste for beneficial use is becoming increasingly important in resource-limited economy. In this study, waste chicken bones of different parts from restaurant industry were pyrolyzed at 600 °C and evaluated for char physicochemical properties and Pb sorption characteristics. Lead adsorption isotherms by different chicken bone chars were carried out with initial Pb concentration range of 1-1000 mg L-1 at pH 5. The Pb adsorption data were better described by the Langmuir model (R2 = 0.9289-0.9937; ARE = 22.7-29.3%) than the Freundlich model (R2 = 0.8684-0.9544; ARE = 35.4-72.0%). Among the chars derived from different chicken bone parts, the tibia bone char exhibited the highest maximum Pb adsorption capacity of 263 mg g-1 followed by the pelvis (222 mg g-1), ribs (208 mg g-1), clavicle (179 mg g-1), vertebrae (159 mg g-1), and humerus (135 mg g-1). The Pb adsorption capacities were significantly and positively correlated with the surface area, phosphate release amount, and total phosphorus content of chicken bone chars (r ≥ 0.9711). On the other hand, approximately 75-88% of the adsorbed Pb on the chicken bone chars was desorbable with 0.1 M HCl, indicating their recyclability for reuse. Results demonstrated that chicken bone char could be used as an effective adsorbent for Pb removal in wastewater.

Adsorption of Cd, Cu and Zn from aqueous solutions onto ferronickel slag under different potentially toxic metal combination.

Adsorption characteristics of potentially toxic metals in single- and multi-metal forms onto ferronickel slag were evaluated. Competitive sorption of metals by ferronickel slag has never been reported previously. The maximum adsorption capacities of toxic metals on ferronickel were in the order of Cd (10.2 mg g(-1)) > Cu (8.4 mg g(-1)) > Zn (4.4 mg g(-1)) in the single-metal adsorption isotherm and Cu (6.1 mg g(-1)) >> Cd (2.3 mg g(-1)) > Zn (0.3 mg g(-1)) in the multi-metal adsorption isotherm. In comparison with single-metal adsorption isotherm, the reduction rates of maximum toxic metal adsorption capacity in the multi-metal adsorption isotherm were in the following order of Zn (93%) > Cd (78%) >> Cu (27%). The Freundlich isotherm provides a slightly better fit than the Langmuir isotherm equation using ferronickel slag for potentially toxic metal adsorption. Multi-metal adsorption behaviors differed from single-metal adsorption due to competition, based on data obtained from Freundlich and Langmuir adsorption models and three-dimensional simulation. Especially, Cd and Zn were easily exchanged and substituted by Cu during multi-metal adsorption. Further competitive adsorption studies are necessary in order to accurately estimate adsorption capacity of ferronickel slag for potentially toxic metals in natural environments.

Competitive adsorption and selectivity sequence of heavy metals by chicken bone-derived biochar: Batch and column experiment.

The objective of this research was to evaluate adsorption of heavy metals in single- and ternary-metal forms onto chicken bone biochar (CBB). Competitive sorption of heavy metals by CBB has never been reported previously. The maximum adsorption capacities of metals by CBB were in the order of Cu (130 mg g(-1)) > Cd (109 mg g(-1)) > Zn (93 mg g(-1)) in the single-metal adsorption isotherm and Cu (108 mg g(-1)) >> Cd (54 mg g(-1)) ≥ Zn (44 mg g(-1)) in the ternary-metal adsorption isotherm. Cu was the most retained cation, whereas Zn could be easily exchanged and substituted by Cu. Batch experimental data best fit the Langmuir model rather than the Freundlich isotherms. In the column experiments, the total adsorbed amounts of the metals were in the following order of Cu (210 mg g(-1)) > Cd (192 mg g(-1)) > Zn (178) in single-metal conditions, and Cu (156) > Cd (123) > Zn (92) in ternary-metal conditions. Results from both the batch and column experiments indicate that competitive adsorption among metals increases the mobility of these metals. Especially, Zn in single-metal conditions lost it adsorption capacity most significantly. Based on the 3D simulation graphs of heavy metals, adsorption patterns under single adsorption condition were different than under competitive adsorption condition. Results from both the batch and column experiments show that competitive adsorption among metals increases the mobility of these metals. The maximum metal adsorption capacity of the metals in the column experiments was higher than that in the batch experiment indicating other metal retention mechanisms rather than adsorption may be involved. Therefore, both column and batch experiments are needed for estimating retention capacities and removal efficiencies of metals in CBB.

Conversion of acidified lignin containing sulfur discharged from a biorefinery process into neutralized biochar: Characterization and metal adsorption.

The objectives of this study were to produce biochars using sulfur-rich acidified lignin discharged from a biorefinery process and to evaluate their physicochemical properties and Pb adsorption capacity. As the pyrolysis temperature increased, the lignin acidified by the desulfurization process was converted to neutralized biochar (LBC), which exhibited high carbon content and stability. The carbon content of biochar manufactured at a pyrolysis temperature of 600 °C or higher was over 90 % and showed no significant difference, and their surface structures were found to be different, as revealed through XRD and FTIR analyses. The adsorption capacity of Pb by LBC increased with increasing pyrolysis temperature, and their adsorption capacity was well described by the pseudo-second-order model and the Langmuir isotherm adsorption model. In particular, the internal diffusion effect on the adsorption capacity of Pb was greater for LBC900 than for LBC600. In complex heavy metal solutions, LBC selectively exhibited high affinity for Pb, while the adsorption capacity of other metals was significantly reduced. The adsorption mechanism of Pb by LBC was verified through various analytical methods, and these results demonstrated that the adsorption of Pb by LBC was influenced by functional groups existing on the surface and inside of LBC and by some cation exchange.

Terriglobus aquaticus sp. nov., isolated from an artificial reservoir.

A pink-pigmented, chemo-organotrophic bacterium, designated strain 03SUJ4(T), was isolated from the freshwater of Juam reservoir, Republic of Korea (35° 03' 43'' N 127° 14' 15'' E). Cells were aerobic, Gram-reaction-negative and non-motile rods. Strain 03SUJ4(T) grew at pH 6-7 (optimum, pH 6) and at 15-30 °C (optimum, 25 °C). Phylogenetic analysis based on 16S rRNA gene sequences indicated that the isolate belonged to the genus Terriglobus, showing sequence similarities of 97.09 % and 96.82 % to Terriglobus roseus DSM 18391(T) and Terriglobus saanensis SP1PR4(T), respectively. Low rpoB gene sequence similarity with members of the genus Terriglobus and different fingerprints with the repetitive primers BOX, ERIC and REP indicated that the isolate represented a novel species of the genus Terriglobus. The major cellular fatty acids were iso-C15 : 0, C16 : 0, C20 : 1ω9c, C14 : 0 and summed feature 3 (C16 : 1ω7c/C16 : 1ω6c). The DNA G+C content of strain 03SUJ4(T) was 63.2±0.1 mol% (mean±sd of three determinations). The predominant menaquinone was MK-8. The major polar lipids were phosphatidylethanolamine, diphosphatidylglycerol, phosphatidylglycerol and two unidentified phospholipids. Several phenotypic characteristics served to differentiate the novel isolate from recognized members of the genus Terriglobus. On the basis of the evidence presented in this study, a novel species, Terriglobus aquaticus sp. nov. is proposed for strain 03SUJ4(T) ( = KCTC 23332(T) = JCM 17517(T)).

Colonization of Listeria monocytogenes in potting soils as affected by bacterial community composition, storage temperature, and natural amendment.

This study aimed to characterize the bacterial community of commercial potting soils with or without Listeria monocytogenes inoculation at 5-35 °C using 16S metagenomic sequencing and evaluate the effect of natural amendments on the reduction L. monocytogenes in non-sterile potting soils. An increase in the expected operational taxonomic units of each sample with or without L. monocytogenes was proportional to the increasing storage temperatures after 5 days. Biodiversity was distinct among all potting soils for Shannon and inverse Simpson indices, with the highest diversity being observed in a soil sample stored at 35 °C for 5 days with L. monocytogenes. An increase in richness and diversity of soil bacterial community structure positively correlated with less survival of the invading L. monocytogenes. Particularly, garlic extract was demonstrated as a promising soil-amendment substrate, reducing L. monocytogenes by ≥ 4.50 log CFU/g in potting soils stored at 35 °C. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s10068-021-00925-9.

Exploration of the potential capacity of fly ash and bottom ash derived from wood pellet-based thermal power plant for heavy metal removal.

This study was conducted to explore the potential capacity for the removal of heavy metals from the fly ash (FA) and bottom ash (BA) emitted by wood pellet thermal power plants. Fly ash consists of inorganic compounds such as CaSiO3, P2O5, and K2O, whereas BA shows properties very similar to the biochar derived from organic biomass. The adsorption properties of both FA and BA for Cd were described well by the Langmuir and pseudo-second-order models, and the maximum adsorption capacity of FA for Cd was 4.2 times higher than that of BA. The results indicate that FA can be applied to the treatment of wastewater that contains heavy metals over pH range from 2-6; however, BA is considered to be most effective for application with wastewater that contains heavy metals at a pH of 5-6. Study of the mechanism concluded that the adsorption of Cd by FA is dominated by the formation of Cd2SiO4 complexes by chemical reactions between CaSiO3 and Cd ions as well as via the precipitation of Cd(OH)2 in the neutral and alkaline solutions that is caused by the dissolution of K. It was found that the adsorption of Cd by BA was influenced by the binding of functional groups (CC and COH), coupled CaCO3 dissolution-CdCO3 precipitation reaction and ion exchange between some minerals with Si and Cd ions in weakly acidic conditions. Results indicate that the FA and BA emitted from wood pellet thermal power plants have high potential for heavy metal removal, and their practical use in the purification and restoration of heavy metals could be an effective way to reduce the waste produced by power plants and clean the environment.

Evaluation of a hybrid constructed wetland for treating domestic sewage from individual housing units surrounding agricultural villages in South Korea.

The treatment efficiency of 2- and 3-stage constructed wetlands (CWs) was evaluated for treating domestic sewage from houses surrounding agricultural villages. The optimum depth of filter media was 90 cm. The optimum volume ratio of vertical flow (VF) and horizontal flow (HF) beds was 1:2, and the optimum filter medium was broken stone in the VF-HF 2-stage hybrid CWs. Based on the above optimum conditions, removal efficiency of biochemical oxygen demand (BOD), chemical oxygen demand (COD), suspended solids (SS), total nitrogen (T-N), and total phosphorus (T-P) were 99, 98, 99, 68, and 72%, respectively. However to utilize constructed wetlands (CWs) for treating domestic sewage for an individual house, would require downsizing of the 2-stage hybrid CWs. In addition, the low removal efficiency of T-N and T-P in 2-stage hybrid CWs would require improvements necessary to meet acceptable water quality discharge standards. Thus, to reduce the CWs' area and improve the T-N and T-P removal efficiencies, VF-HF 2-stage hybrid CW was modified into VF/HF(I)-HF(II) and VF/HF(I)-HF(III) 3-stage hybrid CW. The optimum reduced size of 3-stage hybrid CW was the VF/HF(I)-HF(II) configuration which also increased T-N removal. Using this system, removal efficiency of BOD, COD, SS, T-N, and T-P were 99, 98, 99, 83, and 75%, respectively. In VF/HF(I)-HF(II) CW, the removal velocity of BOD, COD and SS was rapid on the order of VF (1st stage) >> HF(II) (3rd stage) > or = HF(I) (2nd stage), VF (1st stage) >> HF(II) (3rd stage) > HF(I) (2nd stage) and VF (1st stage) >> HF(I) (2nd stage) > HF(II) (3rd stage), respectively. The removal velocity of T-N and T-P in VF/HF(I)-HF(II) CWs was rapid on the order of HF(I) (2nd stage) > HF(II) (3rd stage) > or = VF (1st stage) and VF (1st stage) > HF(I) (2nd stage) > HF(II) (3rd stage), respectively.

Cadmium adsorption characteristics of biochars derived using various pine tree residues and pyrolysis temperatures.

This study investigated the characteristics of biochars derived using various pine tree residues and pyrolysis temperatures and evaluated their Cd adsorption behaviors. The characteristics of pine tree residue biochars (PRBs) were dominantly affected by the pyrolysis temperature, and the optimum pyrolysis temperature for Cd adsorption was 600 °C. The adsorption of Cd by PRBs was divided into two stages: rapid adsorption on the initial boundary layer and slow adsorption by intraparticle diffusion. The Cd adsorption characteristics of all the PRBs were well described by pseudo-second-order and Langmuir isotherm models, and the maximum adsorption capacity was the highest in pine bark biochar (85.8 mg/g). The amounts of the cations released from the mixed pine tree residue biochars (M-PRBs) during Cd adsorption were increased, while the amount of phosphate released was decreased, indicating that exchangeable cations and phosphate on the biochar affected the Cd adsorption. In particular, the amount of Cd removed by the exchangeable cations corresponds to 23.6% of the total adsorption amount. Spectroscopic analyses using FTIR showed that the Cd adsorption on M-PRB was associated with functional groups such as CC, COH and COOH. Overall, the use of biochars derived from pine tree residue as an adsorbent is considered to be effective for both the treatment of wastewater containing heavy metals and the recycling of forest residues.

Mercury adsorption in the Mississippi River deltaic plain freshwater marsh soil of Louisiana Gulf coastal wetlands.

Mercury adsorption characteristics of Mississippi River deltaic plain (MRDP) freshwater marsh soil in the Louisiana Gulf coast were evaluated under various conditions. Mercury adsorption was well described by pseudo-second order and Langmuir isotherm models with maximum adsorption capacity of 39.8 mg g-1. Additional fitting of intraparticle model showed that mercury in the MRDP freshwater marsh soil was controlled by both external surface adsorption and intraparticle diffusion. The partition of adsorbed mercury (mg g-1) revealed that mercury was primarily adsorbed into organic-bond fraction (12.09) and soluble/exchangeable fraction (10.85), which accounted for 63.5% of the total adsorption, followed by manganese oxide-bound (7.50), easily mobilizable carbonate-bound (4.53), amorphous iron oxide-bound (0.55), crystalline Fe oxide-bound (0.41), and residual fraction (0.16). Mercury adsorption capacity was generally elevated along with increasing solution pH even though dominant species of mercury were non-ionic HgCl2, HgClOH and Hg(OH)2 at between pH 3 and 9. In addition, increasing background NaCl concentration and the presence of humic acid decreased mercury adsorption, whereas the presence of phosphate, sulfate and nitrate enhanced mercury adsorption. Mercury adsorption in the MRDP freshwater marsh soil was reduced by the presence of Pb, Cu, Cd and Zn with Pb showing the greatest competitive adsorption. Overall the adsorption capacity of mercury in the MRDP freshwater marsh soil was found to be significantly influenced by potential environmental changes, and such factors should be considered in order to manage the risks associated with mercury in this MRDP wetland for responding to future climate change scenarios.

Effect of biochar derived from barley straw on soil physicochemical properties, crop growth, and nitrous oxide emission in an upland field in South Korea.

This study was conducted to investigate soil quality, Chinese cabbage growth, and N2O emission after biochar application in an upland field in South Korea. Each of the barley straw biochar (BC, applied at 10 ton ha-1), inorganic fertilizer (IF, applied at N-P-K = 320-78-198 kg ha-1), and BC + IF treatment areas were separated by a control (Cn) treatment area. Soils treated with BC and BC + IF treatments had lower bulk density and higher porosity than those in the Cn treatment areas. Soil chemical properties (pH, TN, Avail. P2O5, and CEC) after biochar addition were improved. In particular, soil pH and CEC related to crop nutrient availability were significantly increased in BC areas compared to those in Cn and IF areas. Fresh weights of Chinese cabbage grown under BC, IF, and BC + IF treatment conditions increased by 64.9, 78.4, and 112.0%, respectively, over that in the Cn treatment area. Total nutrient (TN, TP, and K) uptakes among the treatment areas were, in declining order, BC + IF (14.51 g plant-1) > IF > BC > Cn. More interestingly, the BC application had a positive effect on growth of Chinese cabbage under IF application conditions, and there was a tight relationship between the effect of BC application on Chinese cabbage growth and that of agronomic IF application efficiency. Compared to the IF results, total N2O flux was lower with BC (flux decreased by 60.6%) or BC + IF (flux decreased by 22.3%) treatments. These results indicate that Chinese cabbage yield, when cultivated in soil conditions such as those in an upland field in South Korea, can be increased by application of BC or a combination of BC and IF.

Effect of pyrolysis temperature on phosphate adsorption characteristics and mechanisms of crawfish char.

The purpose of this study was to investigate the characteristics of crawfish char (CFC) derived at different pyrolysis temperature and to evaluate its adsorption characteristics on phosphate. Phosphate adsorption by CFC occurred rapidly at the beginning of the reaction, and the time to reach equilibrium was dependent on the pyrolysis temperature. Maximum adsorption capacities of phosphate by CFC at different pyrolysis temperatures were high in order of CFC800 (70.9 mg/g) > CFC600 (56.8 mg/g) > CFC400 (47.2 mg/g) ≫ CFC200 (9.5 mg/g) ≈ uncharred crawfish feedstock (CF) (7.1 mg/g). Spectroscopic analyses using SEM-EDS and FTIR showed that the phosphate present in the CFC itself was associated with carbon, while the phosphate adsorbed on the CFC was closely related to calcium. The adsorption of phosphate by CFC is dominantly affected by pH. Phosphate adsorption of CFC600 primarily occurred at acid and neutral pH which is related to dissolved calcium from surface and phosphate hydrolysis product (H2PO4-), while phosphate adsorption of CFC800 mainly took place at alkaline pH, with precipitation mechanism between PO43- and calcium dissolved from free CaO and Ca(OH)2. Overall, CFC derived at pyrolysis temperatures above 400 °C is effective for waste reduction and phosphate treatment in wastewater.

Degradation of Orange G by Fenton-like reaction with Fe-impregnated biochar catalyst.

This study was conducted to evaluate the catalytic activity of Fe-impregnated sugarcane biochar (FSB) for removing azo dye Orange G (OG) from solution under various Fenton-like oxidation conditions. The optimum molar Fe concentration for impregnation to achieve maximum catalytic activity of FSB in Fenton-like reaction with acceptable effluent Fe release was 0.25 M (163.4 Fe mg/g in FSB). High removal efficiency of 99.7% was achieved within 2 h of reaction at optimum conditions of 0.075 g/L H2O2, 0.5 g/L FSB for 0.1 g/L OG at initial pH 5.5 under 25 °C. For every 10 °C increase, the time for maximum OG degradation efficiency decreased by 0.5 h. The OG removal by FSB exhibited a slow induction reaction followed by fast OG decomposition. FSB can be used successively for at least 4 runs with >89.3% OG removal. The FSB was more economical, efficient, and recyclable than other conventional Fenton oxidation catalysts.

One-Pot Transformation of Technical Lignins into Humic-Like Plant Stimulants through Fenton-Based Advanced Oxidation: Accelerating Natural Fungus-Driven Humification.

Commercial humic acids mainly obtained from leonardite are in increasing demand in agronomy, and their market size is growing rapidly because these materials act as soil conditioners and direct stimulators of plant growth and development. In nature, fungus-driven nonspecific oxidations are believed to be a key to catabolizing recalcitrant plant lignins, resulting in lignin humification. Here we demonstrated the effective transformation of technical lignins derived from the Kraft processing of woody biomass into humic-like plant fertilizers through one-pot Fenton oxidations (i.e., artificially accelerated fungus reactions). The lignin variants resulting from the Fenton reaction, and manufactured using a few different ratios of FeSO4 to H2O2, successfully accelerated the germination of Arabidopsis thaliana seeds and increased the tolerance of this plant to NaCl-induced abiotic stress; moreover, the extent of the stimulation of the growth of this plant by these manufactured lignin variants was comparable or superior to that induced by commercial humic acids. The results of high-resolution (15 T) Fourier transform-ion cyclotron resonance mass spectrometry, electrostatic force microscopy, Fourier transform-infrared spectroscopy, and elemental analyses strongly indicated that oxygen-based functional groups were incorporated into the lignins. Moreover, analyses of the total phenolic contents of the lignins and their sedimentation kinetics in water media together with scanning electron microscopy- and Brunauer-Emmett-Teller-based surface characterizations further suggested that polymer fragmentation followed by modification of the phenolic groups on the lignin surfaces was crucial for the humic-like activity of the lignins. A high similarity between the lignin variants and commercial humic acids also resulted from autonomous deposition of iron species into lignin particles during the Fenton oxidation, although their short-term effects of plant stimulations were maintained whether the iron species were present or absent. Finally, we showed that lignins produced from an industrial-scale acid-induced hydrolysis of wood chips were transformed with the similar enhancements of the plant effects, indicating that our fungus-mimicking processes could be a universal way for achieving effective lignin humification.

Gene expression profiling of cancer stem cell in human lung adenocarcinoma A549 cells.

BACKGROUND: The studies on cancer-stem-cells (CSCs) have attracted so much attention in recent years as possible therapeutic implications. This study was carried out to investigate the gene expression profile of CSCs in human lung adenocarcinoma A549 cells. RESULTS: We isolated CSCs from A549 cell line of which side population (SP) phenotype revealed several stem cell properties. After staining the cell line with Hoechst 33342 dye, the SP and non-side population (non-SP) cells were sorted using flow cytometric analysis. The mRNA expression profiles were measured using an Affymetrix GeneChip(R) oligonucleotide array. Among the sixty one differentially expressed genes, the twelve genes inclusive three poor prognostic genes; Aldo-keto reductase family 1, member C1/C2 (AKR1C1/C2), Transmembrane 4 L six family member 1 nuclear receptor (TM4SF1), and Nuclear receptor subfamily 0, group B, member 1 (NR0B1) were significantly up-regulated in SP compared to non-SP cells. CONCLUSION: This is the first report indicating the differences of gene expression pattern between SP and non-SP cells in A549 cells. We suggest that the up-regulations of the genes AKR1C1/C2, TM4SF1 and NR0B1 in SP of human adenocarcinoma A549 cells could be a target of poor prognosis in anti-cancer therapy.

Bioavailability of the amino acid-attached prodrug as a new anti-HIV agent in rats.

The primary objective of this study was to compare the pharmacokinetics of a new anti-human immunodeficiency virus agent 1-(2-amino-pyridin-4-ylmethyl)-6-(3,5-dimethylbenzoyl)-5-isopropyl-1H-pyrimidine-2,4-dione (VP-0502) with its amino acid prodrug alanine amide of VP-0502 (VP-0502AL), following intravenous and oral administrations to rats. The plasma concentrations of both analytes were analyzed via high-performance liquid chromatography coupled with photodiode-array detection (HPLC-DAD). When VP-0502 was intravenously administered at 20 mg/kg, the analyte appeared in low levels with an AUC of 0.3 microg . h/ml, and C(0) of 0.2 microg/ml in plasma. However, both the prodrug VP-0502AL and its metabolite VP-0502 appeared at comparatively higher levels following intravenous injection of VP-0502AL at the same dose. VP-0502AL's pharmacokinetic parameters were V(d): 4.6 l/kg; AUC: 3 microg . h/ml; t(1/2): 0.5 h; C(0): 6 microg/ml; CL(tot): 7 l/h/kg; and MRT: 0.6 h. Following oral administration of VP-0502 (100 mg/kg), it was not detectable in plasma (<50 ng/ml), while after the oral administration of VP-0502AL, VP-0502 was quantitatively detected as an active metabolite for the first 7 h, with a maximum plasma concentration (C(max)) of 0.8 microg/ml, and an area under the concentrationtime curve (AUC) of 2 microg . h/ml. The oral pharmacokinetic parameters of VP-0502AL were calculated to be: maximum concentration time (t(max)) 2.7 h; C(max) 0.2 microg/ml; elimination half-life (t(1/2)): 0.8 h; and AUC 0.5 microg . h/ml. Overall the findings indicate that VP-0502AL has a favorable pharmacokinetic profile as a prodrug with rapid transformation into the active metabolite, and that the attachment of the amino acid alanine to VP-0502 is an effective approach to improve its oral bioavailability. VP-0502AL is predicted to become a new highly bioavailable anti-AIDS drug candidate and/or lead compound.

Competitive adsorption of heavy metals onto sesame straw biochar in aqueous solutions.

Objective of this research was to evaluate adsorption of heavy metals in mono and multimetal forms onto sesame straw biochar (SSB). Competitive sorption of metals by SSB has never been reported previously. The maximum adsorption capacities (mgg(-1)) of metals by SSB were in the order of Pb (102)≫Cd (86)≫Cr (65)>Cu (55)≫Zn (34) in the monometal adsorption isotherm and Pb (88)≫Cu (40)≫Cr (21)>Zn (7)⩾Cd (5) in the multimetal adsorption isotherm. Based on data obtained from the distribution coefficients, Freundlich and Langmuir adsorption models, and three-dimensional simulation, multimetal adsorption behaviors differed from monometal adsorption due to competition. Especially, during multimetal adsorption, Cd was easily exchanged and substituted by other metals. Further competitive adsorption studies are necessary in order to accurately estimate the heavy metal adsorption capacity of biochar in natural environments.