Purification and characterization of the carbonic anhydrase enzyme from Black Sea trout (Salmo trutta Labrax Coruhensis) kidney and inhibition effects of some metal ions on enzyme activity

Multiple forms of carbonic anhydrase in Tetragonia tetragonioides leaves and the impact of heavy metal ions on enzyme activity

Tetragonia tetragonioides (Aizoaceae; Caryophyllales), an annual herbaceous plant, a halophyte native to the marine coasts of New Zealand is now cultivated worldwide as a minor salt-tolerant crop. The aim of this study was to evaluate the activity of carbonic anhydrase (CA, EC 4.2.1.1) and identify the CA isoforms in a fraction of total soluble proteins from T. tetragonioides leaves and to determine CA sensitivity to specific sulfonamide inhibitors and heavy metal (HM) ions. In higher plants, CA is one of the most abundant leaf enzymes catalyzing CO2 and HCO3- interconversions that maintain the balance between dissolved forms of inorganic carbon. Catalytically active CA isoforms in the soluble protein fraction isolated from T. tetragonioides leaves were identified by a protonography method which involves the detection of CA activity in the gel following SDS-PAGE and subsequent removal of SDS (De Luca et al., 2015). This approach enabled the detection of active oligomeric forms of CA in the gel, allowing for the separate assessment of their activity. The protonogram revealed the presence of five sources of CA activity, which correspond to isoforms with approximate molecular masses of 26, 35, 41, 52, and 166 kDa. The total CA activity of T. tetragonioides leaf proteins was found to be inhibited by specific CA inhibitors, acetazolamide (AZ) and ethoxyzolamide (EZ), within the same concentration range as CAs from other plants. The half-maximal inhibition of hydratase activity was estimated to be 16 μM AZ and 2 μM EZ. The in vitro impact of selected heavy metal ions (Cu2⁺, Cd2⁺, Zn2⁺, Pb2⁺, Hg2⁺, and Ag⁺) on the hydratase activity of the soluble T. tetragonioides protein fraction was examined. High sensitivity of CA activity to inhibition by silver (I50-0.5 μM) and mercury ions (I50 ∼ 2 μM) was shown. Copper and cadmium ions inhibited CA activity with I50 ∼ 40 and ∼12 μM, respectively. Zinc ions (I50 ∼ 200 μM) were weaker inhibitors, and lead ions in the concentration range of 50-500 μM insignificantly stimulated the hydratase activity of soluble proteins of T. tetragonioides. The high sensitivity of T. tetragonioides CA to Ag⁺ and Hg2⁺ ions, which are known to act as sulfhydryl poisons, can be attributed to the presence of SH-containing cysteines within the active site of the plant CAs.

Revealing the degrading-possibility of methyl red by two azoreductases of Anoxybacillus sp. PDR2 based on molecular docking

Azo dyes, as the most widely used synthetic dyes, are considered to be one of the culprits of water resources and environmental pollution. Anoxybacillus sp. PDR2 is a thermophilic bacterium with the ability to degrade azo dyes, whose genome contains two genes encoding azoreductases (named AzoPDR2-1 and AzoPDR2-2). In this study, through response surface methodology (RSM), when the initial pH, inoculation volume and Mg2+ addition amount were 7.18, 10.72% and 0.1 g/L respectively, the decolorization rate of methyl red (MR) (200 mg/L) could reach its maximum (98.8%). The metabolites after biodegradation were detected by UV-Vis spectroscopy, Fourier transform infrared spectroscopy (FTIR), and liquid chromatography mass spectrometry (LC-MS/MS), indicating that MR was successfully decomposed into 4-aminobenzoic acid and other small substrates. In homologous modeling, it was found that both azoreductases were flavin-dependent azoreductases, and belonged to the α/β structure, using the Rossmann fold. In their docking results with the cofactor flavin mononucleotide (FMN), FMN bound to the surface of the protein dimer. Nicotinamide adenine dinucleotide (NADH) was superimposed on the plane of the pyrazine ring between FMN and the activity pocket of protein. Besides, both azoreductase complexes (azoreductase-FMN-NADH) exhibited a substrate preference for MR. Asn104 and Tyr74 played an important role in the combination of the azoreductase AzoPDR2-1 complex and the azoreductase AzoPDR2-2 complex with MR, respectively. This provided assistance for studying the mechanism of azoreductase biodegradation of azo dyes in thermophilic bacteria.

Acetylphenyl-substituted imidazolium salts: synthesis, characterization, in silico studies and inhibitory properties against some metabolic enzymes

Herein, we present how to synthesize thirteen new 1-(4-acetylphenyl)-3-alkylimidazolium salts by reacting 4-(1-H-imidazol-1-yl)acetophenone with a variety of benzyl halides that contain either electron-donating or electron-withdrawing groups. The structures of the new imidazolium salts were conformed using different spectroscopic methods (1H NMR, 13C NMR, 19F NMR, and FTIR) and elemental analysis techniques. Furthermore, these compounds' the carbonic anhydrase (hCAs) and acetylcholinesterase (AChE) enzyme inhibition activities were investigated. They showed a highly potent inhibition effect toward AChE and hCAs with Ki values in the range of 8.30 ± 1.71 to 120.77 ± 8.61 nM for AChE, 16.97 ± 2.04 to 84.45 ± 13.78 nM for hCA I, and 14.09 ± 2.99 to 69.33 ± 17.35 nM for hCA II, respectively. Most of the synthesized imidazolium salts appeared to be more potent than the standard inhibitor of tacrine (TAC) against AChE and Acetazolamide (AZA) against CA. In the meantime, to prospect for potential synthesized imidazolium salt inhibitor(s) against AChE and hCAs, molecular docking and an ADMET-based approach were exerted.

Liposomal silymarin anti-oxidative and anti-apoptotic features in lung cells: An implication in cadmium toxicity

BACKGROUND

Several metallic elements with high atomic weight and density are serious systemic toxicants, and their wide environmental distribution increase the risk of their exposure to human. Silymarin (SL), a polyphenol from milk thistle (Silybum marianum) plant has shown protective role against heavy metal toxicity. However, its low aqueous solubility and rapid metabolism limits its therapeutic potential in clinic.

METHODS

We compared the role of silymarin nanoliposomes (SL-L) against cadmium (Cd) toxicity in normal MRC-5 and A 549 cancer cells. MRC-5 and A 549 cells exposed to Cd at 25 and 0.25 µM respectively, were treated with various non-toxic SL-L concentrations (2.5, 5, 10 µM) and cells viability, reactive oxygen species (ROS) generation, apoptosis and levels of cleaved PARP and caspase-3 proteins were determined following incubation.

RESULTS

Results indicated that Cd exposure significantly increased apoptosis due to ROS generation, and showed greater toxicity on cancer cells compared to normal cells. While SL-L at higher concentrations (25 µM and higher) exhibits pro-apoptotic features, lower concentrations (10 and 2.5 µM for MRC-5 and A 549 cancer cells, respectively) played a protective and anti-oxidant role in Cd induced toxicity in both cells. Further, lower SL-L was required to protect cancer cells against Cd toxicity. In general, treatment with SL-L significantly improved cell survival by decreasing ROS levels, cleaved PARP and caspase-3 in both MRC-5 and A 549 cells compared to free silymarin.

CONCLUSION

Results demonstrated that SL-L potential in protecting against Cd-induced toxicity depends on concentration-dependent antioxidant and anti-apoptotic balance.

Purification and biochemical characterization of a novel carbonic anhydrase II from erythrocytes of camel (Camelusdromedarius)

A novel carbonic anhydrase II (CA II) from erythrocytes of camel (Camelus dromedarius) was purified to homogeneity using affinity chromatography and biochemically characterized. Specific activity of 140.88 U/mg was obtained with 745.17-fold purification and 25.37% yield. The enzyme was a monomer with a lower molecular weight (25 kDa) and lower Zn content (0.50 mol of Zn per mol of protein). The enzyme showed higher optimum temperature (70 °C) and pH (pH 9.0), moreover, it was stable at higher temperatures and strongly alkaline pH as judged by thermodynamic parameters (Ea, kd, Ed, t1/2, D-value, Z-value, ΔH, ΔG and ΔS). The enzyme was inhibited by cations (Al3+, Ca2+, Cd2+, Co2+, Cr3+, Cu2+, Fe3+, Ni2+, Mg2+ and Zn2+) as well as by anions (Br‾, CH3COO‾, ClO4‾, CN‾, F‾, HCO3‾, I‾, N3‾, NO3‾ and SCN‾), some anions (C6H5O73-, CO32-, SeO3‾ and SO42-) does not affect enzyme activity. Effect of various chemicals on enzyme activity was also investigated. Km, Vmax, kcat and kcat/Km values for 4-NPA were found to be 1.74 mM, 0.0093 U/mL, 0,0039 s-1 and 0,0023 s-1 mM-1, respectively. With these interesting biochemical properties, camel CA II represents promising candidate for harsh industrial applications, in particular, for a successful biomimetic CO2 sequestration process.

Studying the interaction between the new neodymium (Nd) complex with the ligand of 1,10-phenanthroline with FS-DNA and BSA

To learn more about the chemotherapeutic and pharmacokinetic properties of a neodymium complex containing 1,10-phenanthroline (dafone), In vitro binding was investigated with bovine serum albumin and fish-salmon DNA, using a variety of molecular modeling research and biophysical approaches. A variety of spectroscopic techniques including fluorescence and absorption were used to investigate the interplay between DNA/BSA and the neodymium complex. The findings revealed that the Nd complex had a high affinity for BSA and DNA interplays through van der Waals powers. In addition, the binding of the Nd complex to FS-DNA mainly in the groove binding mode clearly reflects with iodide quenching studies, ethidium bromide (EtBr) exclusion assay, ionic strength effect, and viscosity studies. It was observed that the Nd complex binds to FS-DNA through a minor groove with 3.81 × 105 (M-1). Also, Kb for BSA at 298 K was 5.19×105 (M-1), indicating a relatively high affinity of the Nd complex for DNA and BSA. In addition, a competitive study of a docking investigation revealed that the neodymium complex interacts at BSA site III. The results obtained from the binding calculations are well consistent with the experimental findings. Also, cytotoxicity studies of Nd complex were performed in MCF-7 and A-549 cell lines and the results show that this new complex has a selective inhibitory effect on the growth of various cancer cells.

Urease and Carbonic Anhydrase Inhibitory Effect of Xanthones from Aspergillus nidulans, an Endophytic Fungus of Nyctanthes arbor-tristis

Urease plays a major role in the pathogenesis of peptic and gastric ulcer and also causes acute pyelonephritis and development of infection-induced reactive arthritis. Carbonic anhydrases (CA) cause pathological disorders such as epilepsy (CA I), glaucoma, gastritis, renal, pancreatic carcinomas, and malignant brain tumors (CA II). Although various synthetic urease and carbonic anhydrase inhibitors are known, these have many side effects. Hence, present studies were undertaken on ethyl acetate extract of Aspergillus nidulans, an endophytic fungus separated from the leaves of Nyctanthes arbor-tristis Linn. and led to the isolation of five furanoxanthones, sterigmatin (1: ), sterigmatocystin (3: ), dihydrosterigmatocystin (4: ), oxisterigmatocystin C (5: ), acyl-hemiacetal sterigmatocystin (6: ), and a pyranoxanthone (2: ). Acetylation of 3: gave compound O-acetyl sterigmatocystin (7: ). Their chemical structures were elucidated by ¹H and ¹³C NMR and MS. The inhibitory effect of isolated compounds was evaluated on urease and carbonic anhydrase (bCA II) enzymes in vitro. Compounds 3: and 6: showed significant urease inhibition (IC₅₀ 19 and 21 µM), while other compounds exhibited varying degrees of urease inhibition (IC₅₀ 33 - 51 µM). Compounds 4, 6: and 7: exhibited significant inhibition of bCA II (IC₅₀ values 21, 25 and 18 µM respectively), compounds 1: -3: displayed moderate inhibition (IC₅₀ 61, 76 and 31 µM respectively) while 5: showed no inhibition. A mechanistic study of the most active urease inhibitors was also performed using enzyme kinetics and molecular docking. All compounds were found non-toxic on the NIH-3T3 cell line.

Carvacrol protects against λ-Cyhalothrin-induced hepatotoxicity and nephrotoxicity by modulating oxidative stress, inflammation, apoptosis, endoplasmic reticulum stress, and autophagy

λ-Cyhalothrin, a type II synthetic pyrethroid, has been widely used in households, agriculture, public health, and gardening to control insect pests. Despite its widespread usage, it is known to induce a variety of adverse effects, including hepatotoxicity and nephrotoxicity. The goal of this study was to investigate the protective effect of carvacrol, which has antioxidant, anti-inflammatory, anti-apoptotic, and some other properties, on λ-Cyhalothrin-induced hepatotoxicity and nephrotoxicity 35 male Sprague-Dawley rats were randomly divided into five groups for this purpose: I-Control group: II-CRV group (50 mg/kg carvacrol), III-LCT group (6.23 mg/kg LCT), IV-LCT + CRV 25 group (6.23 mg/kg LCT + 25 mg/kg carvacrol), and V-LCT + CRV 50 group (6.23 mg/kg LCT + 50 mg/kg carvacrol). Using biochemical, real-time PCR, and western blotting methods, the collected tissues were analyzed. While λ-Cyhalothrin treatment increased MDA levels, which are indicated of lipid peroxidation, but reduced SOD, CAT, GPx activities, and GSH levels. After receiving carvacrol therapy, the degree of oxidative stress reduced as the values of these parameters approached those of the control group. Increased inflammation, apoptosis, endoplasmic reticulum stress, and autophagy with λ-Cyhalothrin administration reduced with carvacrol co-administration, and liver and kidney tissues were protected from damage, depending on the degree of oxidative stress. After considering all of these data, it was discovered that λ-Cyhalothrin-induced oxidative stress, inflammation, apoptosis, endoplasmic reticulum stress, and autophagy in the liver and kidneys; however, carvacrol protected the tissues from damage. Our findings indicate that carvacrol may be a promising protective agent in λ-Cyhalothrin-induced hepatotoxicity and nephrotoxicity.

Vinyl functionalized 5,6-dimethylbenzimidazolium salts: Synthesis and biological activities

A series of vinyl functionalized 5,6-dimethylbenzimidazolium salts are synthesized. All compounds were fully characterized by elemental analyses, MS, ¹ H-NMR, ¹³ C-NMR, and IR spectroscopy techniques. Enzyme inhibition is a very active area of research in drug design and development. In this study, the synthesized novel benzimidazolium salts were evaluated toward the human erythrocyte carbonic anhydrase I (hCA I), and II (hCA II) isoenzymes, acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) enzymes. They demonstrated highly potent inhibition ability against hCA I with K_i values of 484.8 ± 62.6-1389.7 ± 243.2 nM, hCA II with K_i values of 298.9 ± 55.7-926.1 ± 330.0 nM, α-glycosidase with K_i values of 170.3 ± 27-760.1 ± 269 μM, AChE with K_i values of 27.1 ± 3-77.6 ± 1.7 nM, and BChE with K_i values of 21.0 ± 5-61.3 ± 15 nM. As a result, novel vinyl functionalized 5,6-dimethylbenzimidazolium salts (1a-g) exhibited effective inhibition profiles toward studied metabolic enzymes. Therefore, we believe that these results may contribute to the development of new drugs particularly to treat some global disorders including glaucoma, Alzheimer's disease, and diabetes.

Comprehensive Metabolite Profiling of Cinnamon (Cinnamomum zeylanicum) Leaf Oil Using LC-HR/MS, GC/MS, and GC-FID: Determination of Antiglaucoma, Antioxidant, Anticholinergic, and Antidiabetic Profiles

In this study, for the first time, the antioxidant and antidiabetic properties of the essential oil from cinnamon (Cinnamomum zeylanicum) leaves were evaluated and investigated using various bioanalytical methods. In addition, the inhibitory effects of cinnamon oil on carbonic anhydrase II (hCA II), acetylcholinesterase (AChE), and α-amylase, which are associated with various metabolic diseases, were determined. Further, the phenolic contents of the essential oil were determined using LC-HRMS chromatography. Twenty-seven phenolic molecules were detected in cinnamon oil. Moreover, the amount and chemical profile of the essential oils present in cinnamon oil was determined using GC/MS and GC-FID analyses. (E)-cinnamaldehyde (72.98%), benzyl benzoate (4.01%), and trans-Cinnamyl acetate (3.36%) were the most common essential oils in cinnamon leaf oil. The radical scavenging activities of cinnamon oil were investigated using 1,1-diphenyl-2-picryl-hydrazil (DPPH•), 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid), and (ABTS•+) bioanalytical scavenging methods, which revealed its strong radical scavenging abilities (DPPH•, IC50: 4.78 μg/mL; and ABTS•+, IC50: 5.21 μg/mL). Similarly, the reducing capacities for iron (Fe3+), copper (Cu2+), and Fe3+-2,4,6-tri(2-pyridyl)-S-triazine (TPTZ) were investigated. Cinnamon oil also exhibited highly effective inhibition against hCA II (IC50: 243.24 μg/mL), AChE (IC50: 16.03 μg/mL), and α-amylase (IC50: 7.54μg/mL). This multidisciplinary study will be useful and pave the way for further studies for the determination of antioxidant properties and enzyme inhibition profiles of medically and industrially important plants and their oils.

Benzimidazolium Salts Containing Trifluoromethoxybenzyl: Synthesis, Characterization, Crystal Structure, Molecular Docking Studies and Enzymes Inhibitory Properties

The method for producing 4-trifluoromethoxybenzyl substituted benzimidazolium salts is described in this article. The method is based on the reaction of 4-trifluoromethoxybenzyl substituent alkylating agent with 1-alkylbenzimidazole. This method yielded 1-(4-trifluoromethoxybenzyl)-3-alkylbenzimidazolium bromide salts. These benzimidazolium salts were characterized by using ¹ H-NMR, ¹³ C-NMR, FT-IR spectroscopy, and elemental analysis techniques. The crystal structure of 1f was enlightened by single crystal X-ray diffraction studies. Also, the enzyme inhibition effects of the synthesised compounds were investigated. They demonstrated highly potent inhibition effect on acetylcholinesterase (AChE) and carbonic anhydrases (hCAs) (K_i values are in the range of 7.24±0.99 to 39.12±5.66 nM, 5.57±0.96 to 43.07±11.76 nM, and 4.38±0.43 to 18.68±3.60 nM for AChE, hCA I, and hCA II, respectively). In molecular docking study, the interactions of active compounds showing activity against AChE and hCAs enzymes were examined. The most active compound 1f has -10.90 kcal/mol binding energy value against AChE enzyme, and the potential structure compound 1e, which has activity against hCA I and hCA II enzymes, was -7.51 and -8.93 kcal/mol, respectively.

Synthesis of Novel Bromophenol with Diaryl Methanes—Determination of Their Inhibition Effects on Carbonic Anhydrase and Acetylcholinesterase

In this work, nine new bromophenol derivatives were designed and synthesized. The alkylation reactions of (2-bromo-4,5-dimethoxyphenyl)methanol (7) with substituted benzenes 8–12 produced new diaryl methanes 13–17. Targeted bromophenol derivatives 18–21 were synthesized via the O-Me demethylation of diaryl methanes with BBr3. Moreover, the synthesized bromophenol compounds were tested with some metabolic enzymes such as acetylcholinesterase (AChE), carbonic anhydrase I (CA I), and II (CA II) isoenzymes. The novel synthesized bromophenol compounds showed Ki values that ranged from 2.53 ± 0.25 to 25.67 ± 4.58 nM against hCA I, from 1.63 ± 0.11 to 15.05 ± 1.07 nM against hCA II, and from 6.54 ± 1.03 to 24.86 ± 5.30 nM against AChE. The studied compounds in this work exhibited effective hCA isoenzyme and AChE enzyme inhibition effects. The results show that they can be used for the treatment of glaucoma, epilepsy, Parkinson’s as well as Alzheimer’s disease (AD) after some imperative pharmacological studies that would reveal their drug potential.

Regulatory effects of marine polysaccharides on gut microbiota dysbiosis: A review

The gut microbiota dysbiosis is a state which the physiological combinations of flora are transformed into pathological combinations caused by factors such as diets, pollution, and drugs. Increasing evidence shows that dysbiosis is closely related to many diseases. With the continuous development and utilization of marine resources, marine polysaccharides have been found to regulate dysbiosis in many studies. In this review, we introduce the types of dysbiosis and the degree of it caused by different factors. We highlight the regulating effects of marine polysaccharides on dysbiosis as a potential prebiotic. The mechanisms of marine polysaccharides to regulate dysbiosis including protection of intestinal barrier, regulatory effect on gut microbiota, alteration for related metabolites, and some other possible mechanisms were summarized. And we aim to provide some references for the high-value utilization of marine polysaccharides and new targets for the treatment of gut microbiota dysbiosis by this review.

A metal chaperone OsHIPP16 detoxifies cadmium by repressing its accumulation in rice crops

Cadmium (Cd) is an environmentally polluted toxic heavy metal and seriously risks food safety and human health through food chain. Mining genetic potentials of plants is a crucial step for limiting Cd accumulation in rice crops and improving environmental quality. This study characterized a novel locus in rice genome encoding a Cd-binding protein named OsHIPP16, which resides in the nucleus and near plasma membrane. OsHIPP16 was strongly induced by Cd stress. Histochemical analysis with pHIPP16::GUS reveals that OsHIPP16 is primarily expressed in root and leaf vascular tissues. Expression of OsHIPP16 in the yeast mutant strain ycf1 sensitive to Cd conferred cellular tolerance. Transgenic rice overexpressing OsHIPP16 (OE) improved rice growth with increased plant height, biomass, and chlorophyll content but with a lower degree of oxidative injury and Cd accumulation, whereas knocking out OsHIPP16 by CRISPR-Cas9 compromised the growth and physiological response. A lifelong trial with Cd-polluted soil shows that the OE plants accumulated much less Cd, particularly in brown rice where the Cd concentrations declined by 11.76-34.64%. Conversely, the knockout oshipp16 mutants had higher levels of Cd with the concentration in leaves being increased by 26.36-35.23% over the wild-type. These results suggest that adequate expression of OsHIPP16 would profoundly contribute to Cd detoxification by regulating Cd accumulation in rice, suggesting that both OE and oshipp16 mutant plants have great potentials for restricting Cd acquisition in the rice crop and phytoremediation of Cd-contaminated wetland soils.

Phthalimide-tethered imidazolium salts: Synthesis, characterization, enzyme inhibitory properties, and in silico studies

A series of new imidazolium salts were prepared in good yield by the reaction between 1-alkylimidazole and a variety of alkyl halides. The structures of the compounds were identified by FT-IR, ¹ H NMR, and ¹³ C NMR spectroscopy, elemental analysis, and mass spectrometry. The crystal structure of 1b was determined by the single-crystal X-ray diffraction method. The phthalimide-tethered imidazolium salts exhibited inhibition abilities toward acetylcholinesterase (AChE) and human carbonic anhydrases (hCAs) I and II, with K_i values in the range of 24.63 ± 3.45 to 305.51 ± 35.98 nM for AChE, 33.56 ± 3.71 to 218.01 ± 25.21 nM for hCA I and 17.75 ± 0.96 to 308.67 ± 13.73 nM for hCA II. The results showed that the new imidazolium salts can play a key role in the treatment of Alzheimer's disease, epilepsy, glaucoma, and leukemia, which is related to their inhibition abilities of hCA I, hCA II, and AChE. Molecular docking and in silico absorption, distribution, metabolism, excretion and toxicity studies were used to look into how the imidazolium salts interacted with the specific protein targets. To better visualize and understand the binding positions and the influence of the imidazolium salts on hCA I, hCA II, and AChE conformations, each one was subjected to molecular docking simulations.

The palladium-based complexes bearing 1,3-dibenzylbenzimidazolium with morpholine, triphenylphosphine, and pyridine derivate ligands: synthesis, characterization, structure and enzyme inhibitions

The palladium-based complexes bearing N-heterocyclic carbene (NHC) ligand have long attracted attention as active catalysts for many catalytic reactions. Recently, the biological activities of these complexes, which are stable to air and moisture, have also been wondered. With the aim, we report the synthesis of a series of (NHC)Pd(Br2)(L) complexes (NHC: 1,3-dibenzylbenzimidazolium, L: morpholine, triphenylphosphine, pyridine, 3-chloropyridine, and 2-aminopyridine). All complexes were characterized by NMR (1H and 13C), FTIR spectroscopic and elemental analysis techniques. In addition, the single crystal structures of the complex 3, 4, and 6 were determined through single crystal x-ray crystallographic method. Furthermore, the carbonic anhydrase I and II isoenzymes (hCAs) and acetylcholinesterase (AChE) inhibition effects of these palladium-based complexes bearing NHC ligand were investigated. They showed highly potent inhibition effect with Ki values are between 10.06 ± 1.49-68.56 ± 11.53 nM for hCA I isoenzyme, 7.74 ± 0.66 to 49.39 ± 6.50 nM for hCA II isoenzyme and 22.83 ± 3.21 to 64.09 ± 9.05 nM for AChE enzyme.

Physiological and Transcriptomic Analysis provide Molecular Insight into 24-Epibrassinolide mediated Cr(VI)-Toxicity Tolerance in Pepper Plants

The ever-increasing industrial activities over the decades have generated high toxic metals such as chromium (Cr) that hampers plant growth and development. To counter Cr-toxicity, plants have evolved complex defensive systems including hormonal crosstalk with various signaling pathways. 24-epibrassinolide (24-EBR) lowers oxidative stress and alleviates Cr(VI)-toxicity in plants. In this study, the concealed BR-mediated influences on Cr(VI)-stress tolerance were explored by transcriptome analysis in the Capsicum annuum. Results revealed a linkage between plant development under Cr(VI)-stress and the mitigating effect of 24-epibrassinolide and brassinazole. Growth inhibition, chlorophyll degradation, and a significant rise of malondialdehyde (MDA) were observed after 40 mg/L Cr(VI) treatment in Brz supplemented seedlings, whereas 24-EBR supplemented seedlings exhibited commendatory effect. Comparative transcriptome analysis showed that the expression levels of 6687 genes changed (3846 up-regulated and 2841 downregulated) under Cr(VI)-stress with Brz supplementation. Whereas the expression levels of only 1872 genes changed under Cr(VI)-stress with 24-EBR supplementation (1223 up-regulated and 649 downregulated). The functional categories of the differentially expressed genes (DEGs) by gene ontology (GO) revealed that drug transport, defense responses, and drug catabolic process were the considerable enrichments between 24-EBR and Brz supplemented seedlings under Cr(VI)-stress. Furthermore, auxin signaling, glutathione metabolism, ABC transporters, MAPK pathway, and 36 heavy metal-related genes were significantly differentially expressed components between Cr(VI)-stress, 24-EBR, and Brz supplemented seedlings. Overall, our data demonstrate that employing 24-EBR can commendably act as a growth stimulant in plants subjected to Cr(VI)-stress by modulating the physiological and defense regulatory system.

Phloretin exhibits potential food-drug interactions by inhibiting human UDP-glucuronosyltransferases in vitro

Phloretin is a well-known apple polyphenol possessing a wide variety of biological effects and has been widely used in many fields. However, it's unclear whether phloretin has an effect on the activity of human UGT enzymes. Our study indicated that phloretin inhibited human UGTs on a broad spectrum. Further kinetic analysis revealed that phloretin inhibited UGT1A1, 1A6, 1A9, 2B7, and 2B15 in a noncompetitive manner, with calculated K_i of 8.34 μM, 16.69 μM, 10.58 μM, 17.74 μM and 2.46μΜ, respectively, whereas phloretin inhibited UGT1A7 in an un-competitive manner, with calculated K_i of 5.70 μM. According to the quantitative risk prediction, co-administration of phloretin with drugs primarily metabolized by UGT1A7 and/or UGT2B15 may result in potential food-drug interactions. To sum up, when phloretin or phloretin-rich food is administered with medications metabolized by UGT1A7 and/or UGT2B15, concern should be exercised.

Biological activity and molecular docking studies of some N-phenylsulfonamides against cholinesterases and carbonic anhydrase isoenzymes

In this research, a series of N-phenylsulfonamide derivatives (1-12) were designed, synthesized and investigated for their inhibitory potencies against carbonic anhydrase isoenzymes I, II and IX (hCA I, hCA II, and hCA IX) and cholinesterases (ChE), namely, acetylcholinesterase (AChE) and butyrylcholinesterase (BChE). These compounds, whose inhibition potentials were evaluated for the first time, were characterized by spectroscopic techniques (¹ H- and ¹³ C NMR and FT-IR). CA isoenzyme inhibitors are significant therapeutic targets, especially owing to their preventive/activation potential in the therapy processes of some diseases such as cancer, osteoporosis, and glaucoma. On the other hand, Cholinesterase inhibitors are valuable molecules with biological importance that can be employed in the therapy process of Alzheimer's patients. The results showed that the tested molecules had enzyme inhibition activities ranging from 9.7 to 93.7 nM against these five metabolic enzymes. Among the tested molecules, the methoxy and the hydroxyl group-containing compounds 10, 11, and 12 exhibited more enzyme inhibition activities when compared to standard compounds acetazolamide (AAZ), sulfapyridine, and sulfadiazine for CA isoenzymes and neostigmine for ChE, respectively. Of these three molecules, compound 12, which had a hydroxyl group in the para position in the aromatic ring, was determined to be the most active molecule against all enzymes. In silico work, molecular docking has also shown similar results and consistent with the experimental data in the study. As a result, we can say that some of the tested molecules might be used as promising inhibitor candidates for further studies on this topic.

Metal-binding biomolecules in the liver of northern pike (Esox lucius Linnaeus, 1758): The first data for the family Esocidae

Metal-handling strategies of various fish species are known to vary significantly in association with their intracellular metal behaviour. Thus, to better understand the possible consequences of increased metal exposure in fish it is important to perform comparative studies on metal-binding biomolecules in organs of different species. This study was the first of this kind on a liver of an esocid fish (northern pike, Esox lucius), and the gathered information were compared to fish belonging to three other families, Leuciscidae, Cyprinidae and Salmonidae. Distributions of ten elements among cytosolic biomolecules of different molecular masses were studied by size exclusion HPLC combined offline with high resolution ICP-MS. The results indicated predominant association of Co, Fe and Mo to high molecular mass biomolecules (>100 kDa), of Zn and Bi to both high and medium molecular mass biomolecules (>30 kDa), of Mn and Se to medium molecular mass biomolecules (30-100 kDa), and Ag, Cd and Cu to low molecular mass biomolecules (10-30 kDa), presumably metallothioneins. Evident binding to metallothioneins was also detected for Zn and Bi. For several metals, distinct differences were observed when cytosolic metal distributions of northern pike were compared to leuciscids, salmonids and cyprinids. More pronounced Zn binding to metallothioneins was recorded in leuciscids and cyprinids than both esocids and salmonids, whereas cytosolic Mn and Se distributions clearly differed between all studied fish families. Accordingly, in assessment of metal pollution it is vital to consider the exposed species, which requires prior comprehensive comparative research on numerous aquatic organisms.

Investigation of the effects of hesperidin administration on abamectin-induced testicular toxicity in rats through oxidative stress, endoplasmic reticulum stress, inflammation, apoptosis, autophagy, and JAK2/STAT3 pathways

In this study, the potential effects of hesperidin (HES) on chronic toxicity caused by abamectin (ABM) in the testicular tissue were investigated through oxidative stress, inflammation, endoplasmic reticulum stress (ERS), apoptosis, and autophagy pathways. Male Sprague Dawley rats were used in the study. Animals in the ABM group were orally administered 1 mg/kg ABM every other day for 28 days, while HES used against ABM was given at 100 or 200 mg/kg 30 min after ABM administration for 28 days. Markers of oxidative stress, inflammation, ERS, apoptosis, and autophagy in the testicular tissues removed after the animals are sacrificed were analyzed using biochemical, real-time polymerase chain reaction (RT-PCR), or western blot techniques. The results obtained showed that ABM caused oxidative stress, and triggered ERS, inflammation, apoptosis, and autophagy. On the other hand, HES showed antioxidant effect by increasing superoxide dismutase, catalase, glutathione peroxidase enzyme activities, and glutathione levels in testis tissue and attenuated lipid peroxidation. Accordingly, MAPK14 reduced the NF-κB, IL-1β, TNF-α, and IL-6 expression levels, presenting an anti-inflammatory effect. In addition, Bax protected against apoptosis and autophagy by reducing the caspase-3, beclin-1, LC3A, and LC3B expressions, and increasing Bcl-2 expression. It was observed that HES also interrupted the JAK2/STAT3 signaling pathway by suppressing IL-6 expression. Taken into consideration together, HES provided significant protection against the destruction caused by ABM in testicular tissue with antioxidant, anti-inflammatory, antiapoptotic, and anti-autophagic effects. Thus, it was revealed that HES has the potential to serve as an alternative treatment option in ABM toxicity.

New Pd(II) complexes of the bisthiocarbohydrazones derived from isatin and disubstituted salicylaldehydes: Synthesis, characterization, crystal structures and inhibitory properties against some metabolic enzymes

Pd(II) complexes (Pd1, Pd2, and Pd3) were synthesized for the first time using asymmetric isatin bisthiocarbohydrazone ligands and PdCl₂(PPh₃)₂. All complexes were characterized by a range of spectroscopic and analytical techniques. The molecular structures of Pd1 and Pd3 have been determined by single-crystal X-ray diffraction analysis. The complexes are diamagnetic and exhibit square planar geometry. The asymmetric isatin bisthiocarbohydrazone ligands coordinate to Pd(II) ion in a tridentate manner, through the phenolic oxygen, imine nitrogen and thiol sulfur, forming five- and six-membered chelate rings within their structures. The fourth coordination site in these complexes is occupied by PPh₃ (triphenylphosphine). The free ligands and their Pd(II) complexes were evaluated for their carbonic anhydrase I, II (hCAs) and acetylcholinesterase (AChE) inhibitor activities. They showed a highly potent inhibition effect on AChE and hCAs. K_i values are in the range of 9 ± 0.6 - 30 ± 5.4 nM for AChE, 7 ± 0.5 - 16 ± 2.2 nM for hCA I and 3 ± 0.3-24 ± 1.9 nM for hCA II isoenzyme. The results clearly demonstrated that the ligands and their Pd(II) complexes effectively inhibited the used enzymes.

A comprehensive analysis on source-distribution-bioaccumulation-exposure risk of metal(loid)s in various vegetables in peri-urban areas of Shenzhen, China

The health risk induced by metal(loid)s in crops are becoming increasingly serious. In this study, eight major vegetables and rhizosphere soils were collected in a peri-urban area with intense electronic information manufacturing activities. The source, distribution and bioaccumulation of six typical metal(loid)s in different vegetable species were analyzed, and exposure risk through vegetable ingestion was estimated. Results showed that vegetables and agricultural soils in the study area suffered from serious metal(loid)s pollution, especially for Cd and Pb. The bioaccumulation capacity differed greatly among individual metal(loid)s and vegetable categories. In general, the highest transfer factors (TF) for Cd, Pb, and As were found in leafy vegetables, while leguminous vegetables had the highest TF of Cu and Zn and root vegetables had the highest TF for Cr. Significant correlations were found between concentrations in vegetables and rhizosphere soils for most metal(loid)s, the exceptions being Pb and Zn. The enrichment of Pb, Cd, Cr and As was mainly attributed to electronic information manufacturing activities, while the enrichment of Zn, Cu and Cd was associated with the application of commercial fertilizers and pesticides. The health risk associated with vegetable intake decreased in the order of leafy > fruit > leguminous > root vegetables. Leafy vegetables were identified as the category with the highest risk, with the mean risk value of 1.26. Cd was the major risk element for leafy vegetables. The non-carcinogenic risks estimated for leguminous and root vegetables were under the acceptable level. In conclusion, special attention should be paid to the health risks of toxic metal(loid)s in leafy vegetables in peri-urban areas with intense electronic information manufacturing activities. In order to minimize health risk, it is necessary to identify low-risk crops based on a comprehensive consideration of the metal(loid)s' pollution characteristics, transfer factors and local people's consumption behaviors.

Biochemical characterization of a novel azo reductase named BVU5 from the bacterial flora DDMZ1: application for decolorization of azo dyes

One of the main mechanisms of bacterial decolorization and degradation of azo dyes is the use of biological enzymes to catalyze the breaking of azo bonds. This paper shows the expression and properties of a novel azo reductase (hybrid-cluster NAD(P)-dependent oxidoreductase, accession no. A0A1S1BVU5, named BVU5) from the bacterial flora DDMZ1 for degradation of azo dyes. The molecular weight of BVU5 is about 40.1 kDa, and it contains the prosthetic group flavin mononucleotide (FMN). It has the decolorization ability of 80.1 ± 2.5% within 3 min for a dye concentration of 20 mg L⁻¹, and 53.5 ± 1.8% even for a dye concentration of 200 mg L⁻¹ after 30 min. The optimum temperature of enzyme BVU5 is 30 °C and the optimum pH is 6. It is insensitive to salt concentration up to a salinity level of 10%. Furthermore, enzyme BVU5 has good tolerance toward some metal ions (2 mM) such as Mn²⁺, Ca²⁺, Mg²⁺ and Cu²⁺ and some organic solvents (20%) such as DMSO, methanol, isopentyl, ethylene glycol and N-hexane. However, the enzyme BVU5 has a low tolerance to high concentrations of denaturants. In particular, it is sensitive to the denaturants guanidine hydrochloride (GdmCl) (2 M) and urea (2 M). Analysis of the dye substrate specificity shows that enzyme BVU5 decolorizes most azo dyes, which is indicating that the enzyme is not strictly substrate specific, it is a functional enzyme for breaking the azo structure. Liquid chromatography/time-of-flight/mass spectrometry (LC-TOF-MS) revealed after the action of enzyme BVU5 that some intermediate products with relatively large molecular weights were produced; this illustrates a symmetric or an asymmetric rapid cleavage of the azo bonds by this enzyme. The potential degradation pathways and the enzyme-catalyzed degradation mechanism are deduced in the end of this paper. The results give insight into the potential of a rapid bio-pretreatment by enzyme BVU5 for processing azo dye wastewater.

The combination of BVU5 enzyme and coenzyme NADH can quickly degrade the azo dye RB5.

Metal Ions, Metal Chelators and Metal Chelating Assay as Antioxidant Method

Heavy metals are essential for a wide range of biological processes, including the growth and reproduction of cells, synthesis of biomolecules, many enzymatic reactions, and the body’s immunity, but their excessive intake is harmful. Specifically, they cause oxidative stress (OS) and generate free radicals and reactive oxygen species (ROS) in metabolism. In addition, the accumulation of heavy metals in humans can cause serious damage to different organs, especially respiratory, nervous and reproductive and digestive systems. Biologically, metal chelation therapy is often used to treat metal toxicity. This process occurs through the interaction between the ligand and a central metal atom, forming a complex ring-like structure. After metals are chelated with appropriate chelating agents, their damage in metabolism can be prevented and efficiently removed from the body. On the other hand, heavy metals, including Zn, Fe and Cu, are necessary for the suitable functioning of different proteins including enzymes in metabolism. However, when the same metals accumulate at levels higher than the optimum level, they can easily become toxic and have harmful effects toward biomolecules. In this case, it induces the formation of ROS and nitrogen species (RNS) resulting in peroxidation of biological molecules such as lipids in the plasma membrane. Antioxidants have an increasing interest in many fields due to their protective effects, especially in food and pharmaceutical products. Screening of antioxidant properties of compounds needs appropriate methods including metal chelating assay. In this study, a general approach to the bonding and chelating properties of metals is described. For this purpose, the basic principles and chemical principles of metal chelation methods, both in vivo and in vitro, are outlined and discussed. Hence, in the main sections of this review, the descriptions related to metal ions, metal chelating, antioxidants, importance of metal chelating in biological system and definitions of metal chelating assays as widely used methods to determine antioxidant ability of compounds are provided. In addition, some chemical properties, technical and critical details of the used chelation methods are given.

Selenourea and thiourea derivatives of chiral and achiral enetetramines: Synthesis, characterization and enzyme inhibitory properties

A series of chiral and achiral cyclic seleno- and thiourea compounds bearing benzyl groups on N-atoms were prepared from enetetramines and appropriate Group VI elements in good yields. All the synthesized compounds were characterized by elemental analysis, FT-IR, ¹H NMR and ¹³C NMR spectroscopy, and the molecular and crystal structures of (R,R)-4b and (R,R)-5b were confirmed by the single-crystal X-ray diffraction method. These assayed for their activities against metabolic enzymes acetylcholinesterase, butyrylcholinesterase, and α-glycosidase. These selenourea and thiourea derivatives of chiral and achiral enetetramines effectively inhibit AChE and BChE with IC₅₀ values in the range of 3.32-11.36 and 1.47-9.73 µM, respectively. Also, these compounds inhibited α-glycosidase enzyme with IC₅₀ values varying between 1.37 and 8.53 µM. The results indicated that all the synthesized compounds exhibited excellent inhibitory activities against mentioned enzymes as compared with standard inhibitors. Representatively, the most potent compound against α-glycosidase enzyme, (S,S)-5b, was 12-times more potent than standard inhibitor acarbose; 7b and 8a as most potent compounds against cholinesterase enzymes, were around 5 and 13-times more potent than standard inhibitor tacrine against achethylcholinesterase (AChE) and butyrylcholinesterase (BChE), respectively.

Ameliorative effects of astaxanthin against copper(II) ion-induced alteration of pentose phosphate pathway and antioxidant system enzymes in rats

Copper (Cu) is one of the toxic elements that cause environmental pollution. As a result of excessive accumulation of copper in the organism, it causes damage in various organs and tissues and hemolysis in erythrocytes. Astaxanthin (ATX) is a pigment belonging to the xanthophyll family, which is an oxygenated derivative of carotenoids. Thanks to its powerful antioxidant properties, ATX has an extraordinary potential to protect the organism against various diseases, especially cancer. The main objective of this study was to investigate the toxic effect of copper ions on the glucose 6-phosphate dehydrogenase (G6PD), 6-phospho-gluconate dehydrogenase (6PGD), glutathione reductase (GR), glutathione S-transferase (GST), and thioredoxin reductase (TrxR) enzymes and the role of astaxanthin in reducing this effect. In in vivo study, Wistar Albino male rats (n=28) were randomly divided into 4 groups: the control group, copper (Cu2+) group, astaxanthin (ATX) group, and copper + astaxanthin (Cu2++ATX) group. The results show that G6PD enzyme activity in Cu2+ group was strongly inhibited (p ˂ 0.05), while in other groups, there were no significant effects compared to the control group (p ⩾ 0.05). 6PGD enzyme activity was significantly reduced in Cu2+ group compared to that in the control group (p ˂ 0.05), and GR enzyme activity was lower in Cu2+ group compared to that in the control group (p ˂ 0.05). Similarly, when GST enzyme activity was evaluated, a strong decrease was observed in the Cu2+ group compared to that in the control group (p ˂ 0.05), while the enzyme activity in the Cu2++ATX group approached the control group (p ⩾ 0.05). When TrxR enzyme activity level was examined, a statistically significant decrease was observed in the Cu2+ and Cu2++ATX groups (p ˂ 0.05), and the enzyme activity in the ATX group was found to be close to that in the control group. When in vitro results were evaluated, it was observed that copper ions inhibited G6PD enzyme purified from rat erythrocyte tissues with IC50=1.90 μM value and Ki = 0.97 μM ± 0.082 value and the inhibition was non-competitive. From the results, it can be concluded that Cu2+ ions have an inhibitory effect on rat erythrocyte pentose phosphate pathway and antioxidant system enzymes both in vivo and in vitro, and astaxanthin reduces this effect.

Cholinesterases, carbonic anhydrase inhibitory properties and in silico studies of novel substituted benzylamines derived from dihydrochalcones

A series of novel urea, sulfamide and N,N-dipropargyl substituted benzylamines were synthesized from dihydrochalcones. The synthesized compounds were evaluated for their cholinesterases and carbonic anhydrase inhibitory actions. The known dihydrochalcones were converted into four new benzylamines via reductive amination. N,N-Dipropargylamines, ureas and sulfamides were synthesized following the reactions of benzylamines with propargyl bromide, N,N-dimethyl sulfamoyl chloride and N,N-dimethyl carbamoyl chloride. The novel substituted benzylamines derived from dihydrochalcones were evaluated against some enzymes such as human erythrocyte carbonic anhydrase I and II isoenzymes (hCA I and hCA II), acetylcholinesterase (AChE) and butyrylcholinesterase (BChE). The novel substituted benzylamines derived from dihydrochalcones exhibited K_i values in the range of 0.121-1.007 nM on hCA I, and 0.077-0.487 nM on hCA II closely related to several pathological processes. On the other hand, K_i values were found in the range of 0.112-0.558 nM on AChE, 0.061-0.388 nM on BChE. As a result, novel substituted benzylamines derived from dihydrochalcones showed potent inhibitory profiles against indicated metabolic enzymes. In addition, Induced-Fit Docking (IFD) simulations and ADME prediction studies have also been carried out to elucidate the inhibition mechanisms and drug-likeness of the synthesized compounds. Therefore, these results can make significant contributions to the treatment of some global diseases, especially Alzheimer's diseases and glaucoma, and the development of new drugs.

Inhibition Profiles of Some Symmetric Sulfamides Derived from Phenethylamines on Human Carbonic Anhydrase I, and II Isoenzymes

In this work, the inhibitory effect of some symmetric sulfamides derived from phenethylamines were determined against human carbonic anhydrase (hCA) I, and II isoenzymes, and compared with standard compound acetazolamide. IC₅₀ values were obtained from the Enzyme activity (%)-[Symmetric sulfamides] graphs. Also, K_i values were calculated from the Lineweaver-Burk graphs. Some symmetric sulfamides compounds (11-18) demonstrated excellent inhibition effects against hCA I, and II isoenzymes. These compounds demonstrated effective inhibitory profiles with IC₅₀ values in ranging from 21.66-28.88 nM against hCA I, 14.44-30.13 nM against hCA II. Among these compounds, the best K_i value for hCA I (K_i : 8.34±1.60 nM) and hCA II (K_i : 16.40±1.00 nM) is compound number 11. Besides, the IC₅₀ value of acetazolamide used as a standard was determined as hCA I, hCA II 57.75 nM, 49.50 nM, respectively. Moreover, in silico ADME-Tox study showed that all synthesized compounds (11-18) had good oral bioavailability in light of Jorgensen's rule of three, and of Lipinski's rule of five.

A novel 7α-hydroxysteroid dehydrogenase: Magnesium ion significantly enhances its activity and thermostability

7α-Hydroxysteroid dehydrogenase (7α-HSDH) plays an important role in the efficient biotransformation of taurochenodeoxycholic acid (TCDCA) to tauroursodeoxycholic acid (TUDCA). In this paper, a novel NADP(H)-dependent 7α-HSDH (named J-1-1) was discovered, heterologously expressed in Escherichia coli and biochemically characterized. J-1-1 exhibited high enzymatic activities. The specific activities of J-1-1 toward TCDCA, glycochenodeoxycholic acid (GCDCA) and ethyl benzoylacetate (EBA) were 188.3 ± 0.2, 217.6 ± 0.4, and 20.0 ± 0.2 U·mg^-1, respectively, in 50 mM Glycine-NaOH, pH 10.5. Simultaneously, J-1-1 showed high thermostability; 73% of its activity maintained after heat treatment at 40 °C for 100 h. Particularly noteworthy is that magnesium ion could stabilize the structure of J-1-1, resulting in the enhancement of its enzymatic activity and thermostability. The enzymatic activity of J-1-1 increased 40-fold in the presence of 50 mM Mg²⁺, and T_0.5 increased by approximately 6 °C. Furthermore, after heat treatment at 40 °C for 20 min, the control group only retained 52% of the residual enzyme activity, while the residual enzyme activity of the experimental group was still 77% of the J-1-1 enzyme activity with Mg²⁺ and without heat treatment. These properties of 7α-HSDH would be expected to contribute to more extensive applications in the biotransformation of related substrates.

Partial purification and characterization of Aspergillus niger inulinase produced from sugar-beet molasses in the shaking incubator and stirred-tank bioreactors

The objectives of this study were to purify Aspergillus niger inulinase produced from sugar-beet molasses in the shaking incubator (100 mL) and stirred-tank bioreactors (5-L and 30-L) by using some downstream processes and to determine enzyme kinetics and characterization. The results showed that the best centrifuge-time combination was 16,873 ×g-5 min with the purification coefficient of 1.4. Besides, with the ultrafiltration process, the inulinase activities yielded using the shaking incubator, pH-controlled/uncontrolled small-scale bioreactors, and large-scale bioreactor were increased from 1101.3, 2079.2, 1561.3, and 787.5 U/mL to 12,065.2, 21,789.0, 11,296.9, and 2948.1 U/mL with purification coefficients of 5.33, 1.38, 1.46, and 1.67, respectively. Additionally, for the inulinase from shaking incubator and pH-uncontrolled bioreactor, the values of K_m for inulin and sucrose were 17.8 and 49.4 mg/mL and 28.8 and 25.9 mg/mL, respectively. As the enzyme amount added to the substrate increased, the activity also increased. Mn²⁺ is the activator of the enzyme, and Cu²⁺ and Ag⁺ are inhibitors of the enzyme. The molecular weight of inulinase has been determined to be between 60 and 70 kDa. Consequently, this study ensures valuable and significant information about the purification and characterization of inulinase for industrial implementations.

Production, purification and applications of raw starch degrading and calcium-independent α-amylase from soil rich in extremophile

Calcium independent, raw starch hydrolyzing, acidic α-amylase (66 kDa) was synthesized by Bacillus subtilis S113 that is an aerobic, rod-shaped and Gram +ve bacteria. Purification of the enzyme was performed by HiTrap Capto Q (Ion-exchange chromatography; 19.28 fold; 22.41% yield). The purified enzyme was found stable at broad acidic pH (4-6.5) and high-temperature range (40-80 °C), that fulfilled the necessary criteria and laid the foundation to be utilized in starch saccharification industry. Kinetic studies of the enzyme revealed that K_m and V_max of the enzyme was 0.22% and 357.14 U/mg respectively. Scanning electron microscopy studies showed that the enzyme was capable of completely hydrolyzing raw wheat and potato starch, further confirming its role in the starch industry. It was found that only 7.93% of the activity was loss at 4 °C when kept for one year.

Concise syntheses and some biological activities of dl-2,5-di-O-methyl-chiro-inositol, dl-1,4-di-O-methyl-scyllo-inositol, and dl-1,6-dibromo-1,6-dideoxy-2,5-di-O-methyl-chiro-inositol

The regio- and stereospecific synthesis of O-methyl-chiro-inositols and O-methyl-scyllo-inositol was achieved, starting from p-benzoquinone. After preparing dimethoxy conduritol-B as a key compound, regiospecific bromination of the alkene moiety of dimethoxy conduritol-B and acid-catalyzed ring opening of dimethoxydiacetate conduritol-B epoxide with Ac₂ O afforded the desired new chiro-inositol derivatives and scyllo-inositol derivative, respectively. Spectroscopic methods were employed for the characterization of all synthesized compounds. The novel inositols (11-17) had effective inhibition profiles against human carbonic anhydrase isoenzymes I and II (hCA I and II) and acetylcholinesterase (AChE). The novel inositols 11-17 were found to be effective inhibitors against AChE, hCA I, and hCA II enzymes. K_i values were calculated in the range of 87.59 ± 7.011 to 237.95 ± 17.75 μM for hCA I, 65.08 ± 12.39 to 538.98 ± 61.26 μM for hCA II, and 193.28 ± 43.13 to 765.08 ± 209.77 μM for AChE, respectively. Also, due to the inhibitory effects of the novel inositols 11-17 against the tested enzymes, these novel inositols are potential drug candidates to treat some diseases such as glaucoma, epilepsy, leukemia, and Alzheimer's disease.

Synthesis of nitrogen, phosphorus, selenium and sulfur-containing heterocyclic compounds - Determination of their carbonic anhydrase, acetylcholinesterase, butyrylcholinesterase and α-glycosidase inhibition properties

Sulfur-containing pyrroles (1-3), tris(2-pyridyl)phosphine(selenide) sulfide (4-5) and 4-benzyl-6-(thiophen-2-yl)pyrimidin-2-amine (6) were synthesized and characterized by elemental analysis, IR and NMR spectra. In this study, the synthesized compounds of nitrogen, phosphorus, selenium and sulfur-containing heterocyclic compounds (1-6) were evaluated against the human erythrocyte carbonic anhydrase I, and II isoenzymes, acetylcholinesterase (AChE), butyrylcholinesterase (BChE), and α-glycosidase enzymes. The synthesized heterocyclic compounds showed IC₅₀ values in range of 33.32-60.79 nM against hCA I, and 37.05-66.64 nM against hCA II closely associated with various physiological and pathological processes. On the other hand, IC₅₀ values were found in range of 13.13-22.21 nM against AChE, 0.54-31.22 nM against BChE, and 13.51-26.55 nM against α-glycosidase as a hydrolytic enzyme. As a result, nitrogen, phosphorus, selenium and sulfur-containing heterocyclic compounds (1-6) demonstrated potent inhibition profiles against indicated metabolic enzymes. Therefore, we believe that these results may contribute to the development of new drugs particularly in the treatment of some global disorders including glaucoma, Alzheimer's disease and diabetes.

Comparison of intracellular trace element distributions in the liver and gills of the invasive freshwater fish species, Prussian carp (Carassius gibelio Bloch, 1782)

Prussian carp (Carassius gibelio) is an invasive freshwater fish known for its high tolerance to aquatic pollution. Our aim was to try to clarify its tolerance to increased exposure to metals/nonmetals, by determining their cytosolic distributions among peptides/proteins of different molecular masses (MM), which form a part of the fish protective mechanisms. The applied approach consisted of fractionation of gill and hepatic cytosols of Prussian carp from the Croatian river Ilova by size-exclusion high performance liquid chromatography, whereas Cd, Cu, Zn, Fe, Mo, and Se analyses were done by high resolution inductively coupled plasma mass spectrometry. The results indicated high detoxification of Cd by its binding to metallothioneins (MTs) in both fish organs. In addition, binding to MTs was observed for Cu in both organs and for Zn in the liver, whereas clear Zn binding to MTs in the gills was not recorded. Zinc in the gills was predominantly bound to proteins of higher MM (50-250 kDa) and to biomolecules of MM below 2 kDa. Predominant Fe binding to proteins of MM of ~400 kDa (presumably storage protein ferritin) was observed in the liver, whereas in the gills Fe was mainly associated to proteins of MM of ~15-65 kDa (presumably hemoglobin oligomers). Maximum Mo and Se elutions in the liver were noted at 235 kDa and 141 kDa, respectively, and in the gills below 10 kDa. The striking difference was observed between two organs of Prussian carp, with predominant metal/nonmetal binding to high MM proteins (e.g., enzymes, storage proteins) in the liver, and to very low MM biomolecules (<10 kDa) in the gills (e.g., antioxidants, metallochaperones, nonprotein cofactors). Such metal/nonmetal distributions within the gills, as the first site of defense, as well as association of several metals to MTs, indicated highly developed defense mechanisms in some organs of Prussian carp.

Impact Assessment of heavy metal cations to the characteristics of photosynthetic phycocyanin

This work has assessed the impact of typical heavy metal cations on C-phycocyanin in vitro and in silico. At low concentrations (<2×10^-6 mol/L), the influence of Pb²⁺ is the highest on the light absorption of C-phycocyanin trimer. At higher concentrations, however, a new order of influence on the light absorption has been observed with Cd²⁺ < Cu²⁺ < Pb²⁺ < Zn²⁺. The fluorescence polarization has changed from the order of Cd²⁺ < Pb²⁺≈Cu²⁺ < Zn²⁺ to Cd²⁺ < Cu²⁺ < Pb²⁺ < Zn²⁺, when the metal concentrations reaches 2×10^-6 mol/L. The mechanisms for these findings have been studied using FTIR, hydrophobic probe, isothermal titration calorimetry and molecular docking for the analysis of structure disorder of C-phycocyanin. It has been suggested that the secondary structure of C-phycocyanin affects more to the light absorbance while the fluorescence characteristics relies more on the tertiary structure. The interaction between Pb²⁺ and C-phycocyanin is both enthalpically and entropically favoured, whereas the interactions for Cd²⁺, Cu²⁺ and Zn²⁺ are entropically driven. The ion-molecular docking suggests that the structure disorder of C-phycocyanin relies on the molecular interactions with metal ions. The in silico study also showed that the binding cites of Zn²⁺ are closer to chromophores.

Effects of different straw biochars on soil organic carbon, nitrogen, available phosphorus, and enzyme activity in paddy soil

Biochar is widely used as a soil amendment. Enzyme activity is an important factor that reflects soil metabolic activity, and is involved in biochemical processes such as organic matter decomposition and nutrient cycling in soils. However, the effects of biochar prepared for different straw materials on soil enzyme activity and soil nutrients are rarely studied. Through pot experiments, the effects of different straw (wheat, rice, maize) biochars (obtained by pyrolysis at 500 °C) on soil organic carbon, nitrogen, available phosphorus, and enzyme activity were studied in paddy soil. The results showed that the addition of biochar increased the soil organic carbon content, which gradually decreased with the extension of the rice growth period. The soil ammonium nitrogen content gradually decreased as the rice growth period continued; however, the soil nitrate nitrogen content first decreased and then increased over the rice growth period. Soil invertase, phosphatase, and urease activity first increased and then decreased, and the enzyme activity was the highest at the heading stage of rice. At this time, there were also significant correlations between enzyme activity and carbon, nitrogen, and phosphorus levels, except in the case of soil urease activity. The geometric mean of the investigated enzyme activities was the highest after amendment with rice straw biochar. These results indicate that the response of enzyme activity to biochar depends on the biochar feedstock and the rice growth stage.