XAD-2 Resin Research Articles

Selective recovery of glycosylated phenolic compounds from nectarine tree branches (Prunus persica var. nucipersica)

Nectarine tree branches, by-products from the arboriculture, contain phenolic compounds. Six main components were revealed by LC-MS and divided into 3 aglycones (A) (catechin, chlorogenic acid, naringenin) and 3 glycosylated (G) (rutin, isoquercetin and prunin) molecules. To maximize their content in nectarine tree branches extract, the extraction process was optimized. The optimum conditions were found at 55 % ethanol and 90 °C, leading to 9.05 ± 0.80 mg/gDM of catechin, 3.17 ± 0.31 mg/gDM of chlorogenic acid, 1.15 ± 0.01 mg/gDM of naringenin, 1.56 ± 0.08 mg/gDM of rutin, 0.57 ± 0.02 mg/gDM of isoquercetin, and 1.73 ± 0.11 mg/gDM of prunin. The glycosylated-aglycone ratio is equal to 0.276 ± 0.006, meaning that aglycones are predominant. Purification of the extract was carried out by adsorption. A screening of several resins led to the choice of the XAD-7 resin that provides a recovery rate of 66–84 % of glycosylated compounds and 9–46 % of aglycones. The effect of the adsorption process on the evolution of the G/A ratio was studied. Under the studied conditions, this parameter increased by 123 %, mainly due to a good performance of the XAD-7 towards glycosylated components and a low recovery rate of chlorogenic acid.

A comparison of various XAD-Amberlite resins impregnated with dicyclohexyl-18-crown-6 for strontium removal

In the present study, four different varieties of Amberlite resin impregnated with dicyclohexyl-18-crown-6 were employed as an adsorbent for the selective extraction of strontium ions (Sr2+) from nitric acid solutions and dicyclohexyl-18-crown-6 impregnated in XAD-4 resin shows highest adsorption of Sr2+ from nitric acid solution. The effect of important parameters such as concentration of nitric acidic in the medium, adsorbent dosage, contact time, initial Sr (II) concentration and temperature were investigated in a batch system. The results demonstrated that the adsorption rate is high in the first 30 min and equilibrium was achieved after 300 min at 3 mol/L nitric acid medium. The results of the kinetic evaluations fit excellently with the pseudo-second-order model with a correlation coefficient R2 = 0.998. The prepared adsorbent extracts Sr (II) by following the Langmuir isotherm with a maximum adsorption capacity of 9.17 mg/g. Thermodynamic investigations indicated that the Sr (II) adsorption is an exothermic and spontaneous process. Strontium ions desorbed from resin in an acceptable percentage (98.9%) with double distilled water. In addition, the adsorption capability of the adsorbent in real water samples and also the effect of the existence of coexisting ions on the extraction of Sr (II) were assessed.

Biotechnological strategies for controlled accumulation of flavones in hairy root culture of Scutellaria lateriflora L.

Accumulation of medicinally important flavones and acteoside was evaluated in Scutellaria lateriflora hairy root cultures subjected to different experimental strategies – feeding with precursors of phenolics biosynthesis (phenylalanine, cinnamic acid, and sodium cinnamate), addition of elicitors (chitosan, jasmonic acid) and Amberlite XAD-4 and XAD-7 resins and permeabilization with dimethyl sulfoxide (DMSO) and methanol. The production profile of S. lateriflora cultures changed under the influence of the applied strategies. Hairy roots of S. lateriflora were found to be a rich source of wogonoside or wogonin, depending on the treatment used. The addition of sodium cinnamate (1.0 mg/L) was the most effective approach to provide high production of flavonoids, especially wogonoside (4.41% dry weight /DW/; 566.78 mg/L). Permeabilization with DMSO (2 µg/ml for 12 h) or methanol (30% for 12 h) resulted in high biosynthesis of wogonin (299.77 mg/L and 274.03 mg/L, respectively). The obtained results provide new insight into the selection of the optimal growth conditions for the production of in vitro biomass with a significant level of flavone accumulation. The data may be valuable for designing large-scale cultivation systems of hairy roots of S. lateriflora with high productivity of bioactive compounds – wogonin or wogonoside.

Study of the textural properties of non-ionic resins and their influence on polyphenol adsorption and desorption

Abstract Macroporous resins are employed for the purification of polyphenolic extracts. However, the relationship between the adsorption and desorption and the textural properties remains unexplored. Thus, we evaluated the textural properties of HP-20, XAD-16 and SP-825 resins and their impact on adsorption and desorption of specific polyphenols like gallic acid, epigallocatechin, and procyanidin B2. The HP-20 resin exhibited a type II isotherm with macroporous structure, while XAD-16 and SP-825 resins displayed type IV isotherms, typically associated with mesoporous materials. The HP-20 resin demonstrated superior adsorption capacity and rupture points for epigallocatechin (2.37 mg/g, 124 min) and procyanidin B2 (1.29 mg/g, 136 min) compared to SP-825 and XAD-16. Contrary, the SP-825 resin exhibited the highest adsorption capacity (5.34 mg/g) and rupture point (68 min) for gallic acid. However, the desorption was more efficient when HP-20 resin was used for all specific polyphenols. Therefore, for an efficient purification process is necessary to consider the chemical structure of the polyphenol and the textural properties.

Solid-liquid extraction for yttrium recovery using porous polymeric resin (XAD-7) functionalized with D2EHPA

The recovery of yttrium is proposed by applying a solid–liquid extraction process using di-2-ethyl hexylphosphoric acid (D2EHPA) as extracting agent. The extracting agents were supported on a macro porous polymeric resin XAD-7 (solid phase). Yttrium ions extraction and discharge tests were performed, firstly from a synthetic aqueous solution of 100 mg/L Y (liquid phase) at 25 °C with stirring. The effects of pH of aqueous solutions bearing yttrium, volume fraction of extracting agents and the solid/liquid (S/L) ratio on the yttrium recovery were studied. The most favorable conditions for yttrium ions extraction are: 20 vol% D2EHPA functionalized resin, pH = 1.5 and an S/L ratio of 10 mg/mL. The discharge of yttrium ions was done under the same conditions of extraction stage, using a 2 mol/L [H2SO4] as stripping solution. Up to 80% yttrium is extracted, while 75% yttrium is recovered in the striping solution. In all experiments, the reaction equilibrium is reached after 20 min, and the kinetics for the extraction stage was determined as a second-order model. Also, experiments were carried out to discharge the yttrium-loaded resins, and it has been determined that the best pH value to strip the Y ions is 1.5. Cyclic tests of extraction and discharge for yttrium ions show that the functionalized resin can work at least five cycles without decreasing its efficiency. Finally, the proposed process was tested in a real solution with Y ions from a waste fluorescent lamp powder leached in H2SO4, demonstrating the ability to effectively recover yttrium, separating it from various metals from the studied residue.

Macroporous resin purification of phenolics from Irish apple pomace: Chemical characterization, and cellular antioxidant and anti-inflammatory activities

Apple pomace (AP) is a highly prevalent waste product worldwide in the fruit processing sector. This study compared the chemical profile, antioxidant, and anti-inflammatory activities of crude (CE) and an extract purified using XAD-7 resin (PE). The purification process increased the total phenolic content, flavonoids, and tannins by 3.35, 40.31, and 8.87-fold, respectively. The main phenolic compounds identified in PE were phlorizin (20.54 mg/g), chlorogenic acid (10.01 mg/g), and hyperoside (2.77 mg/g). No difference was found between CE and PE in protecting human plasma against oxidation. In human erythrocytes, both CE and PE decreased the reactive oxygen species (ROS) generation and decreased lipoperoxidation. However, PE had stronger anti-inflammatory effects than CE by promoting HO-1 gene expression, suppressing NO production, and inhibiting IL-1β, IL-6, and IL-10 mRNA expression in lipopolysaccharide-challenged RAW.264.7 macrophages. Therefore, purifying apple pomace crude extract is a promising approach to boosting valuable antioxidants and anti-inflammatory phenolics.

TESTING THE USE OF XAD RESIN TO REMOVE SYNTHETIC CONTAMINATION FROM ARCHAEOLOGICAL BONE PRIOR TO RADIOCARBON DATING

ABSTRACTMuseum collections are extremely valuable sources of material for ongoing research, although the conservation history of some objects is not always recorded, which can be problematic for chemical analyses. While most contamination is removed using the acid-base-acid treatment, this may not be the case for cross-linked contamination. The XAD resin protocol was implemented at the radiocarbon (14C) laboratory in the Muséum national d’Histoire naturelle, and the setup was tested using known age bone samples and a consolidated Palaeolithic bone. Known age samples were consolidated with shellac or Paraloid, aged for a month, treated with or without the XAD resin and 14C dated. Bone blank results showed that XAD resin was able to remove shellac, which was not the case for the ABA-only method. Results from VIRI I were more variable and VIRI F was possibly too young to show the effects of the consolidants. Two 14C dates on the Palaeolithic bone after XAD treatment are statistically the same, while a sample without XAD treatment was significantly older, suggesting that the contaminant was not fully removed by the ABA-only treatment. This study demonstrates the potential of the XAD treatment to clean heritage bone samples stored in museums prior to geochemical analyses.

Identification of secondary metabolites containing a diketopiperazine core in extracts from myxobacterial strains with growth inhibition activity against a range of prey species.

Myxobacteria produce a variety of bioactive secondary metabolites, and with a wealth of under-researched species they hold vast potential for undiscovered compounds. With the ever-increasing need for new antibiotics, the development of novel therapeutics is vitally important. Therefore, this study aimed to extract and elucidate antimicrobial metabolites from the following myxobacteria: Myxococcus xanthus CA010 and AB022; Corallococcus exiguus DSM 14696T; Myxococcus stipitatus DSM 14675T; and Corallococcus aberystwythensis AB050AT. Metabolite mixtures were extracted in acetone from XAD-16 resin incubated in liquid cultures and analysed using GC-MS. Bioactivity was identified using a growth inhibition assay against a panel of clinically relevant prey species including Gram-positive and Gram-negative bacteria and a fungus. Growth of Klebsiella pneumoniae and Enterococcus faecalis was most affected by the metabolite mixtures and the mixtures from AB022 and AB050AT were effective against the most prey. GC-MS analysis revealed metabolites with roles in the synthesis and degradation of amino acids and fatty acids, but also identified compounds A and B with a diketopiperazine (DKP) core. With previously confirmed bioactivity of compound A, it is suggested that these DKP compounds are contributing to the antimicrobial activity observed. Furthermore, many compounds could not be identified and so these unknowns present further potential for novel bioactive compounds.

High-efficient removal of tungsten from hafnium by TOA/XAD-7 extraction resin from HCl-HF media

ABSTRACT For removal of the natural isobar 182W interference prior to ultra-trace 182Hf determination by accelerator mass spectrometry, an extraction chromatographic method for separation of Hf from W has been developed by using a newly synthesized tri-n-octylamine (TOA)/XAD-7 resin as the stationary phase and HCl-HF media as the mobile phase. Based on the TOA liquid-liquid extraction studies in HF and HCl-HF solutions at wide concentration range, a maximum separation factor of 8.6 × 103 for W/Hf was obtained in 8 M HCl-0.05 M HF solution. Subsequently, the macroporous organic polymer-based TOA/XAD-7 resin was prepared by vacuum impregnation technique and its morphology, chemical structure and composition were characterized by SEM, EDS, FT-IR, TG-DSC, and EA. The results showed the self-assembly TOA/XAD-7 resin uptakes about 50% of extractant and keeps intact binding characteristic for metal ions. Hence, this resin was employed to investigate the column chromatographic behavior of Hf and W with variable parameters of sample loading and column bed dimensions. As a result, a high yield of more than 99% for Hf and high decontamination factor of 3.2 × 105 for W were achieved under the optimal column condition. The strategy developed provides a simple and efficient alternative to sample preparation for 182Hf measurement.

Isolation and structural determination of cis- and trans-p-coumaroyl-secologanoside (comselogoside) from olive oil waste (alperujo). Photoisomerization with ultraviolet irradiation and antioxidant activities

p-Coumaroyl-6́-secologanoside (comselogoside) is a secoiridoid identified in large amounts in olive fruits, although no studies in vitro or in vivo of comselogoside have been reported. This work focuses on the recovery and purification of this compound from olive mill waste (alperujo). The successive isolation on Amberlite XAD-16 and Sephadex LH-20 resins, allowed a comselogoside extract with 80–85% of purity. A photoisomerization of the vinyl-double bond in the p-coumaroyl moiety occurred when the extract was exposed to ultraviolet radiation and a mixture of the trans and cis-isomers was obtained. Both isomers were characterized using NMR, mass spectroscopy, and UV spectrometry. The J (coupling constant) of the protons on the C7 and C8 on the unsaturated chain were found to be the difference between cis (12.8 Hz) and trans- (15.9 Hz) comselogoside. Cis-isomer exhibited lower radical-scavenging activity than trans, although a synergistic effect occurred when the cis-isomer was supplement by the trans-isomer.

Investigation and elimination of surfactant-induced interferences in anodic stripping voltammetry for the determination of trace amounts of cadmium

This article aims to investigate in detail to what extent surfactants affect the determination of cadmium by anodic stripping voltammetry. In recent years, the production and use of surfactants have been steadily increasing, so that their concentration in environmental water samples is rising. At the same time, it is known that organic compounds, such as surfactants, often hinder the voltammetric determination of trace elements by stripping. Non-ionic (Triton X-100, Brij 35, Tween 20, Tween 60, Tween 80), cationic (CTAB, CTAC, DTAB, HPC) and anionic (DSS, SDS) compounds were selected to investigate the effect of surfactants on the voltammetric signal of cadmium. At the same time, the extent to which the addition of Amberlite resins to the analysed solution eliminates the interfering effect of surfactants was tested. Three types of Amberlite resins XAD-2, XAD-7 and XAD-16 were selected for the study and the ratio of resin weight to solution volume was determined. Finally, the determination of cadmium in surfactant-enriched environmental samples was carried out. The recoveries obtained between 95.5 and 107%, with RSD between 3.4 and 6.2%, confirm the validity and correctness of the proposed procedure All measurements were carried out by anodic stripping voltammetry using a CNTs/SGC electrode modified with a bismuth film as the working electrode.

Highly efficient and selective adsorption of palladium(II) from simulated nuclear waste solution using Amberlite XAD-7 resin impregnated with a phenanthroline-derived diamide

The increasing demand and limited natural resources for rare precious metal palladium render its separation and recovery from secondary sources such as acidic nuclear liquid waste greatly interesting. Herein, a novel Et-Tol-DAPhen extraction resin was prepared by impregnating Amberlite XAD-7 resin with a phenanthroline-derived diamide extractant N,N′-diethyl-N,N′-ditolyl-2,9-diamide-1,10-phenanthroline (Et-Tol-DAPhen), and the adsorption behavior of this new extraction resin towards Pd2+ in HNO3 solution was investigated through the batch and column experiments. The Et-Tol-DAPhen extraction resin exhibited strong adsorbability, high adsorption capacity, excellent selectivity and good reusability for Pd2+ in highly acidic HNO3 solution. In addition, the pseudo-second-order and Langmuir models were applied to understand the adsorption process of Pd2+ on Et-Tol-DAPhen extraction resin, respectively. It demonstrated the characteristics of a uniform single-layer chemisorption. The maximum uptake capacity could reach as high as 74.6 mg g−1 for Pd2+ in 3.0 mol/L HNO3 solution which is much higher than most adsorbent materials of palladium reported before. Furthermore, Et-Tol-DAPhen extraction resin could selectively uptake Pd2+ from a simulated acidic nuclear waste solution containing 20 different kinds of ions with the separation factor SFPd/M values as high as 100 to 10,000. Moreover, although the adsorption efficiency had a slight decrease after 5 times of adsorption-desorption process, it still remained at a high level. This new extraction resin displayed a potential application prospect in the field of separation and recovery of Pd2+ from acidic nuclear liquid waste.

Fungal biodegradation of ellagitannins extracted from rambutan peel

The rambutan peel is a by-product with a high quantity of ellagitannins. When ellagitannins are biodegraded, they produce ellagic acid. This work aimed to extract ellagitannins from rambutan peel and make a solid-state fermentation (SSF) to identify which enzymes are involved in the biodegradation of ellagitannins. Extraction of rambutan ellagitannins (RE) was done by microwave/ultrasound technology, isolated by column chromatography with Amberlite XAD-16 resin, and characterized by HPLC-MS. The SSF was done using RE as substrate at three different concentrations (7.5, 15, and 22.5 g/L), Aspergillus niger GH1, polyurethane foam as support and Czapeck-dox medium in tray reactors. Enzymatic activities cellulase, xylanase, polyphenol oxidase, ellagitannase, tannase, β-glucosidase and α-L-arabinofuranosidase were tested, and ellagic acid was quantified. The microwave/ultrasound allowed the extraction of seven ellagitannins where the major compound was geraniin. SSF allows the biodegradation of geraniin into ellagic acid, and ellagitannase was the enzyme with the highest value (25.49 U/L) at the times of maximum accumulation of ellagic acid (6–12 h of fermentation), indicating that this enzyme is directly associated to the process of biodegradation. Finally, the maximum titles of this enzymatic activity (353.27 U/L) were found at fermentation time of 42 h and RE concentration of 22.5 g/L.

Downstream process intensification for biotechnologically generated hyaluronic acid: Purification and characterization

Hyaluronic acid (HA), an anionic, non-sulfated glycosaminoglycan, has several clinical applications. This study examines several downstream methods for purifying HA with maximum recovery and purity. Following the fermentation of Streptococcus zooepidemicus MTCC 3523 to produce HA, the broth was thoroughly purified to separate cell debris and insoluble impurities using a filtration procedure and a variety of adsorbents for soluble impurities. Nucleic acids, proteins with high molecular weight, were successfully removed from the broth using activated carbons and XAD-7 resins. In contrast, insoluble and low molecular weight impurities were removed using diafiltration, with HA recovery of 79.16% and purity close to 90%. Different analytical and characterization procedures such as Fourier transform-infrared spectroscopy, X-ray diffraction, nuclear magnetic resonance, and scanning electron microscopy validated the presence, purity, and structure of HA. Microbial HA showed activity in tests for 2,2-diphenyl-1-picryl-hydrazyl-hydrate (DPPH) radical-scavenging (4.87 ± 0.45kmolTE/g), total antioxidant capacity (13.32 ± 0.52%), hydroxyl radical-scavenging (32.03 ± 0.12%), and reducing power (24.85 ± 0.45%). The outcomes showed that the precipitation, adsorption, and diafiltration processes are suitable for extracting HA from a fermented broth under the chosen operating conditions. The HA produced was of pharmaceutical grade for non-injectable applications.

Sequestration of Mecoprop herbicide from water using XAD-4 resin impregnated with Aliquat 336 and quantification with Liquid Chromatography-Tandem mass spectrometer (LC-MS/MS)

ABSTRACT Amberlite-XAD 4 resin was modified with ionic liquid (Aliquat-336) for adsorptive removal of Methylchlorophenoxy propionic acid (MCPP). The modification of resin with ionic liquid improved the adsorption of MCPP on Amberlite resin. The modified resin was mesoporous with a high surface area of 418.7 m2 g−1 confirmed by BET-N2 isotherm studies. The functional modification and mechanistic features of the modified resin adsorbent were studied using different techniques such as SEM-EDX, TGA, PXRD, XRF, FT-IR, and XPS. The adsorption capacity of the material 64.7 mg g−1 following pseudo-second-order kinetics. The thermodynamic studies affirmed spontaneity and endothermic adsorption. The reusability of the material was up to three cycles. The modified resin could remove 86% of MCPP in run-off water.

Ce(III) and La(III) ions adsorption using Amberlite XAD-7 resin impregnated with DEHPA extractant: response surface methodology, isotherm and kinetic study

In this paper, the removal efficiency of Cerium (Ce(ΙΙΙ)) and lanthanum (La(ΙΙΙ)) ions from aqueous solution using Amberlite XAD-7 resin impregnated with DEHPA(XAD7-DEHPA) was studied in the batch system. The adsorbent ( XAD7–DEHPA) was characterized by SEM–EDX, FTIR and BET analysis Techniques. The response surface methodology based on the central composite design was applied to model and optimize the removal process and evaluate operating parameters like adsorbent dose (0.05–0.065), initial pH (2–6) and temperature (15–55). Variance analysis showed that the adsorbent dose, pH and temperature were the most effective parameters in the adsorption of Ce(ΙIΙ)and La(IΙI) respectively. The results showed that the optimum adsorption condition was achieved at pH = 6, the optimum amount of absorbent and the equilibrium time equal to 0.6 gr and 180 min, respectively. According to the results, the adsorption percentage of Ce(ΙIΙ) and La(ΙΙΙ) ions onto the aforementioned resin were 99.99% and 78.76% respectively. Langmuir, Freundlich, Temkin and sips isotherm models were applied to describe the equilibrium data. From the results, Langmuir isotherm (R2 (Ce) = 0.999, R2 (La) = 0.998) was found to better correlate the experimental rate data. The maximum adsorption capacity of the adsorbent ( XAD7–DEHPA) for both Ce(IΙI) and La(III) was found to be 8.28 and 5.52 mg g−1 respectively. The kinetic data were fitted to pseudo-first-order, pseudo-second-order and Intra particle diffusion models. Based on the results, the pseudo-first-order model and Intra particle diffusion model described the experimental data as well. In general, the results showed that ( XAD7–DEHPA) resin is an effective adsorbent for the removal of Ce(IΙI) and La(III) ions from aqueous solutions due to its high ability to selectively remove these metals as well as its reusability.

Sugarcane straw extracts: Production and purification by amberlite XAD-2

Sugarcane straw is a byproduct and possible source of phenolic compounds that can be used as a value-added ingredient. Hence, the intent of this study was to extract phenolic compounds from sugarcane straw and purify them to improve their potential biological capacity (e.g. antioxidant capacity).The amberlite microporous resin XAD-2 was used to evaluate the enrichment of polyphenols via adsorption and desorption mechanisms. The purified extract was analyzed by LC-ESI-QqTOF-HRMS resulting in the identification of 54 secondary metabolites, mainly belonging to three major classes namely hydroxybenzoic acids, hydroxycinnamic acids, and flavones. The main compounds were chlorogenic acid, neochlorogenic acid and 3-O-feruloylquinic acid. A small number of monosaccharides were detected in the extract such as glucose, cellobiose, and xylose + arabinose. The purified extract also exhibited a higher antioxidant capacity, measured by ABTS and DPPH methods, when compared with the non-purified one.The purification of the sugarcane straw extract allowed us to obtain an extract rich in phenolic compounds that display improved antioxidant capacity, showing promising potential for food and cosmetic applications.

Dialysis and column chromatography for biomass pyrolysis liquids separation

In the current study, a novel approach for separating value-added chemicals from pine wood residues’ pyrolysis liquids (bio-oil) was effectively carried out. It combined two separation techniques used for the first time in this field: dialysis with water, methanol and acetone, and column chromatography with Amberlite™ XAD7 resin. This strategy made it possible to separate bio-oil into four fractions: (1) pyrolytic lignin, which can be utilized in the synthesis of resins, foams, electrodes, asphalt, etc. (2) acid-rich fraction, with particular relevance to the chemical industry, (3) antioxidant fraction, containing phenolic compounds, with a lot of interest for pharmaceutical and nutraceutical industry, and (4) a final fraction containing the most non-polar chemicals from bio-oil. Thus, it was possible to develop a process that allows the obtention of bioproducts from woody biomass, a residue obtained in significant quantities in the management of non-profitable forests, making a step forward within the context of circular economy and bioeconomy.

Mexican Native Black Bean Anthocyanin-Rich Extracts Modulate Biological Markers Associated with Inflammation.

This work aimed to obtain and characterize anthocyanin-rich extracts (ARE) from native black beans and evaluate their antioxidant and anti-inflammatory potential. The initial extract was obtained by supercritical fluids (RE) and purified using Amberlite® XAD-7 resin (PE). RE and PE were fractionated using countercurrent chromatography, and four fractions were obtained (REF1 and REF2 from RE, PEF1, and PEF2 from PE). ARE and fractions were characterized, and the biological potential was evaluated. ABTS IC50 values ranged from 7.9 to 139.2 (mg C3GE/L), DPPH IC50 ranged from 9.2 to 117.2 (mg C3GE/L), and NO IC50 ranged from 0.6 to143.8 (mg C3GE/L) (p < 0.05). COX-1 IC50 ranged from 0.1 to 0.9 (mg C3GE/L), COX-2 IC50 ranged from 0.01 to 0.7 (mg C3GE/L), and iNOS IC50 ranged from 0.9 to 5.6 (mg C3GE/L) (p < 0.05). The theoretical binding energy for phenolic compounds ranged from -8.45 to -1.4 kcal/mol for COX-1, from -8.5 to -1.8 kcal/mol for COX-2, and from -7.2 to -1.6 kcal/mol for iNOS. RE and REF2 presented the highest antioxidant and anti-inflammatory potential. Countercurrent chromatography effectively isolates and purifies bioactive compounds while maintaining their biological potential. Native black beans present an attractive phytochemical profile and could be used as ingredients in nutraceuticals and functional foods.

The characteristics of CDOM structural composition and the effect on indirect photodegradation of sulfamerazine

Sulfamerazine (SM) is a commonly used antibiotic and have been widely used to control various bacterial infectious diseases. The structural composition of colored dissolved organic matter (CDOM) is known to be a major factor that influences the indirect photodegradation of SM, yet the influence mechanism remains unknown. In order to understand this mechanism, CDOM from different sources was fractionated using ultrafiltration and XAD resin, and characterized using UV–vis absorption and fluorescence spectroscopy. The indirect photodegradation of SM in these CDOM fractions was then investigated. Humic acid (JKHA) and Suwannee River natural organic matter (SRNOM) were used in this study. The results showed that CDOM could be divided into four components (three humic-like components and one protein-like component), and terrestrial humic-like components C1 and C2 were found to be the main components that promote SM indirect photodegradation due to their high aromaticity. The indirect photodegradation of SM was much faster in low molecular weight (MW) solutions, whose structures were dominated by greater aromaticity and terrestrial fluorophores in JKHA and higher terrestrial fluorophores in SRNOM. The HIA and HIB fractions of SRNOM contained large aromaticity and high fluorescence intensities of C1 and C2, resulting in a greater indirect photodegradation rate of SM. The HOA and HIB fractions of JKHA had abundant terrestrial humic-like components and contributed more to SM indirect photodegradation.