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Durio kutejensis, commonly known as Lai durian, has a unique characteristics of a creamy texture and a combination of sweet and bitter tastes. This study aimed to isolate and screen yeast from fruits as a potential probiotic agent. The tests consisted of tolerance to bile salt and gastric acid at pH 2, antibacterial activity against Listeria monocytogenes and Salmonella enteriditis, and hemolytic activity on blood agar medium. The results showed that 40 yeasts isolated from Lai durian fruit and 34 of these isolates grew on YMA medium. The two isolates showed high significance in the probiotic tests. These two isolates were able to grow on bile salt up to a concentration of 2% and gastric acid for up to 6 h, with survival rates of 99.06% and 100%, respectively. Two isolates were identified as Pichia kudriavzevii UNJCC Y-137 and Candida tropicalis UN-JCC Y-140 Therefore, these two yeast isolates can be used as potential probiotic agents. [ABSTRACT FROM AUTHOR]

Ultrashort cationic lipopeptides (USCLs) and quaternary ammonium salts constitute two groups of cationic surfactants with high antimicrobial activity. This study aimed to investigate the influence of quaternization of the amino group of the lysine side chain in USCLs on their antimicrobial, hemolytic and cytotoxic activities. To do this, two series of lipopeptides were synthesized, USLCs and their quaternized analogues containing trimethylated lysine residues — qUSCLs (quaternized ultrashort cationic lipopeptides). Quaternization was performed on a resin during a standard solid-phase peptide synthesis with CH3I as the methylating agent. According to our knowledge, this is the first study presenting on-resin peptide quaternization. The lipopeptides were tested for their antibacterial and antifungal activities against the ESKAPE group (Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa and Klebsiella aerogenes) bacteria and Candida glabrata yeast-like fungus. Most of the compounds proved to be active antimicrobial agents with enhanced activity against Gram-positive strains and fungi and a lower against Gram-negative species. In addition, the antimicrobial activity of lipopeptides was increasing with an increase in hydrophobicity but qUSCLs exhibited usually a poorer antimicrobial activity than their parent molecules. Furthermore, the toxicity against red blood cells and human keratinocytes was assessed. It's worth emphasizing that qUSCLs were less toxic than the parent molecules of comparative hydrophobicity. The results of the study proved that qUSCLs can offer a higher selectivity to pathogens over human cells than that of USCLs. Last but not least, quaternization of the peptides could increase their solubility and therefore their bioavailability and utility. [ABSTRACT FROM AUTHOR]

Schiff bases (S1–S8) were prepared by the reaction of 4-aminophenylacetic acid/5-aminoisophthalic acid with benzaldehyde/acetophenone/benzophenone/anthraquinone in ethanol. The sodium salts (NaS1–NaS8) of the Schiff bases were reacted further with triphenyltin(IV) chloride in methanol for 4 h to produce the organotin derivatives (C1–C8). The structures of the synthesized products (S1–S8 and C1–C8) were verified by elemental analysis, FT-IR analysis, 1H NMR spectroscopy, and thermogravimetry. Elemental analysis (CHN) data agreed well with the chemical composition of compounds. FT-IR spectroscopy demonstrated the isobidentate coordination mode of the carboxylate moiety and a trigonal bipyramidal geometry of Sn(IV) in the solid state of complexes. Proton NMR spectra displayed the signals of the Schiff base skeleton as well as the triphenyltin(IV) moieties in the complexes C1–C8 in their anticipated regions. The thermogravimetric analysis has shown a good agreement between the observed percentages of the evolved contents and residues and the theoretically calculated values. The Schiff bases have shown higher thermal stabilities as compared to their organotin(IV) derivatives, owing to stronger hydrogen bonding in the former case. The complexes exhibited higher antibacterial potential as compared to their free ligand precursors against the tested bacteria (Bacillus subtilis and Escherichia coli). The biological activities were dependent upon the structures of investigated products, nature of incorporated ligand and type (gram-positive or gram-negative) of the bacterial strains. The compounds were also tested for their in vitro hemolytic effects on human red blood cells while using PBS as a negative control (0% lysis) and triton X-100 as a positive control (100% lysis). Cytotoxicity values lie in the range of 1.5–7.9%, which is an acceptable range and renders the safe medicinal uses of all the synthesized products. [ABSTRACT FROM AUTHOR]

The current research work appraises the variation in antioxidant, antibacterial and cytotoxic potential of thyme extracts in relation to different extraction solvents along with phenolics profiling using Reversed-phase HPLC (RP-HPLC). Maximum extract yield (21.60%) was obtained with 80% ethanol, while minimum (15.42%) for 100% ethanol. Maximum total phenolic content (TPC), total flavonoid content (TFC), reducing power, and DPPH radical scavenging activities were exhibited by 80% methanolic extract with contribution 123.60 ± 1.51 mg/100 g, 38.11 ± 0.11 mg/100 g, 0.69 ± 0.36, and 72.35 ± 0.14%, respectively. The tested thyme extracts exhibited considerable antibacterial activities as well. Maximum zone of growth inhibition was observed against Escherichia coli (22.51 ± 1.33 mm) by 100% ethanolic extract. Minimum hemolytic activity (4.59 ± 0.02) was observed in 80% ethanolic extract; whereas blood clot lysis (thrombolytic activity) was offered by 100% methanolic extract (15.42 ± 0.1%). Individual phenolic and flavonoid contents were analyzed by using RP-HPLC which showed that thyme extracts mainly contained benzoic acid (12.91–12.92 µg/g) whereas gallic acid was present in least amount (6.98–7.09 µg/g). The major flavonoid component was myricetin (35.33–181.26 µg/g) followed by kaempferol (9.14–15.20 µg/g). Overall, a considerable variation in the biological activities and phenolics composition of aerial parts of wild thyme were noted as a function of extraction solvents. Based on the properties evaluated in this work, the tested thyme plants may be used as an ingredient in nutra-pharmaceutical products. [ABSTRACT FROM AUTHOR]

The growing appearance of multidrug-resistant bacteria represents one of the greatest challenges in the medical supervision of infectious diseases, and requires the growth of novel antimicrobial agents. Owing to the lower toxicity and cheapness, we have reported facile development of SnS, SnSe and their bulk-nanocomposite (SnSe/SnS) for antimicrobial application. In addition, we have also revealed corresponding hemolytic activities to ensure the effectuality of their antimicrobial capabilities. The antimicrobial properties of SnSe, SnS and SnSe/SnS were studied against Staphylococcus aureus (Gram positive bacteria) and Escherichia coli (Gram negative bacteria), reflecting a considerable control over their growth. SnSe picturized a higher antibacterial potential against the selected bacterial strains as compared to SnS. Notably, SnSe not only exhibited extremely low cytotoxicity itself but it also decreased the cytotoxicity of SnS in SnSe/SnS nanostructure. Relatively lower cytotoxicity of SnSe and SnSe/SnS against erythrocytes affirmed their novel and systematic application as an antimicrobial material compared to SnS. [ABSTRACT FROM AUTHOR]

Pure zinc oxide NPs (ZnO NPs) have been synthesized using a simple eco-friendly approach using fruit extracts of Hyphaene thebaica. XRD pattern indicated zincite and highly crystalline phase of ZnO NPs. UV–Vis spectrum revealed surface plasmon resonance at 372 nm and bandgap of 3.36 eV. FTIR spectrum indicated characteristic Zn–O vibration at 450 cm−1. HRTEM images indicated particle size in the range of 8–23 nm having a quasi spherical morphology. Raman shift was observed at 297 cm−1, 405 cm−1 and 548 cm−1. Excellent protein kinase (PK) inhibition and varying antimicrobial potential against different bacterial and fungal strains is reported. E. coli and A. flavus were found as the most susceptible microbial strains. Hemocompatability of the ZnO NPs was revealed. ZnO NPs indicated a dose dependant cytotoxicity. MTT assay revealed a median lethal concentration (IC50) of 106 µg/mL against Leishmania tropica. Different antioxidant assays indicated the antioxidant potential of ZnO NPs. Hyphaene thebaica mediated ZnO NPs revealed excellent therapeutic performance and can used as a potential candidate for diverse biomedical applications. [ABSTRACT FROM AUTHOR]

A series of 2,3-diaryldibenzo[b]thiophene derivatives have been synthesized via Suzuki coupling reactions in moderate to good yields (59–79%). The synthesized compounds were evaluated for their antithrombolytic, biofilm inhibition, and hemolytic potential. All compounds showed significant biological potential. Compound (4k) revealed excellent antithrombolytic (87.24%) and biofilm inhibition (99.64%) activity. While compound (4i) exhibited an outstanding hemolytic potential (84.53%). The docking studies uncovered that studied compounds interact with streptokinase and plasminogen via hydrogen bonding, π-anion, π–π stacked interactions, and π-sigma bonding type interactions. The results revealed that synthesized benzo[b]thiophene derivatives could be a potential source of therapeutic agents. [ABSTRACT FROM AUTHOR]

Edwardsiella tarda (E. tarda) is distributed widely in a variety of hosts including humans, other mammals and fish, and it is worthwhile to notice that E. tarda -caused fish infections lead to the most important bacterial disease in fish. Considering Eha acting as a transcriptional regulator in E. tarda strain ET13 have been reported previously, to better understand its pathogenesis due to this, a type of cell of epithelial cell line (Caco-2) infection model for the pathogen was established in the laboratory. We focused on studying various parameters such as lactate dehydrogenase release (to measure cytotoxicity) and cell adhesions, both of which are related to the bacterial pathogenesis. Furthermore biofilm formation, hemolytic activity, and adhesion to Caco-2 cells were decreased in an E.tarda mutant strain with deletion in-frame isogenic gene eha (∆eha) compared to the wild-type and the complementary strain eha+ (an engineered construct of ∆eha expressing eha); Meanwhile, we found that hemolytic activity and biofilm formation were significantly enhanced in the strain eha+. Moreover, the ∆eha strain had attenuated pathogenicity in the zebrafish infection model. The data also demonstrated that the series of genes fimA, esrB, gadB, mukF, katB, and katG are regulated by eha based on a quantitative reverse transcription polymerase chain reaction tests and analysis. Thus our research data indicated that eha has an impact on hemolytic activity, biofilm formation, adhesion, and pathogenicity of pathogenic strain ET13 and plays an essential role in manifesting the virulence factors. [ABSTRACT FROM AUTHOR]

Safe blood transfusion is the primary need of all the health care delivery system. Though with the advances of transfusion medicine, the incidences of transfusion risk is gradually reduced, but the adverse transfusion reaction (ATR) of non hemolytic type still prevails. The purpose of this study was to estimate the incidence and pattern of transfusion-related adverse events at our centre. The present retrospective observational study was conducted in the Department of Transfusion Medicine from April 2011 to April 2018, at a multi-organ transplant centre in South India. All the Adverse transfusion reactions were investigated in detail in the blood bank for the clerical errors, immunohematology workup and classified according to their nature with imputability assessment. A total of 140 ATR were reported out of 100,569 blood components distributed during the study period. After the analysis and workup of the reported reactions, majority of the reactions were observed in males (71%, n = 99). Most common symptom presented was Itching/Rashes in 43.6% (n = 61) ATR. Allergic reactions (51.4%, n = 72), were the most commonly encountered ATR followed by FNHTR (25.7%, n = 36). FFP transfusions (0.2%) contributed to the majority of the reactions followed by Red cell transfusion (0.15%). ATR were observed maximum in Hepato-biliary disease and liver transplantation patients (62%) followed by oncology patients (15%). The overall incidence of ATR in our study is 0.14% which is comparatively low compared to other studies due to well established hemovigilance systems. Adoption of more equipped methods & sensitive technology in various areas of blood banking will help to bring down the unwanted adverse transfusion reactions. [ABSTRACT FROM AUTHOR]

In the present report, we focused on the screening of antibacterial, hemolytic and cytotoxic activities of Holothuria parva sea cucumber from the Persian Gulf for potential application in nutraceutical and pharmaceutical products. Ethanol, methanol and aqueous extracts of H. parva were prepared by maceration of milled body wall pieces. Cytotoxicity of extracts was tested using brine shrimp lethality assay. Antibacterial activity of extracts was tested against Vibrio alginolyticus, Vibrio parahaemolyticus, Shigella flexneri Salmonella group D, Escherichia coli and Staphylococcus aureus by serial dilution method. Hemolytic activity of extracts was performed using human erythrocytes. Results showed bacterial inhibition of ethanolic and methanolic extracts against E. coli, V. parahaemolyticus and S. aureus at concentrations higher than 20 µg/ml and minimum bactericidal concentration was observed for ethanolic and methanolic extracts at 500 mg/µl against E. coli. The median lethal concentration for brine shrimp was lowest (61.25 ± 8.53) for methanolic extracts, which shows this extract is more toxic against tested organisms. The methanolic and ethanolic extracts of H. parva showed a high level of hemolytic activity (0.62 ± 0.12 and 0.54 ± 0.9) to tested erythrocytes and were comparable to standard pure saponin, but no such activity was found in aqueous extracts. [ABSTRACT FROM AUTHOR]

Homobimetallic organotin(IV) carboxylates dithiocarboxylates, Ph2SnLCS2Sn(Cl)Ph2 (1) and Ph3SnHLCS2SnPh3 (2) were synthesized by a room temperature reaction of l-lysine monohydrate (H2LH) with potassium hydroxide, carbon disulfide and Ph3SnCl/Ph2SnCl2 in methanol. Heterotrinuclear complexes (Bu2SnLCS2)2Pd (3) and (Bu2SnLCS2)2Pd (4) were also synthesized by a reaction of H2LH with KOH, CS2 and PdCl2(aq) in methanol followed by the treatment with n-Bu2SnCl2/Ph2SnCl2. The products were characterized by elemental analysis, FT-IR, multinuclear NMR (1H, 13C and 119Sn) and electron ionization mass spectroscopy (EIMS). The elemental analysis and mass spectrometry verified the molecular composition and structures of complexes. FT-IR spectroscopy demonstrated monodentate binding behavior of the carboxylate group and chelating mode of the dithiocarbamate moiety. The diorganotin(IV) derivatives 1, 3 and 4 convert their solid-state tetra-coordinated structures into trigonal bipyramidal arrangements in solution. However, triphenyltin(IV) derivative 2 exhibited penta-coordinated environment around Sn(IV) in the solid-state and tetrahedral configuration in the solution form. A square planar environment around Pd(II) was exhibited in the solid state. The investigated products displayed antibacterial/antifungal potential, and their minimal inhibitory concentrations (MIC) values were also demonstrated. The nature of the coordinated metals (Sn + Sn or Sn + Pd) and the substitution pattern at tin play a major role in biological actions of these products. The heterometallic (Pd, Sn) products possessed more potential against fungi than bacteria. The heterobimetallic dibutyltin(IV) complex 3 has shown the lowest hemolytic activity (10.76%), while its phenyltin(IV) counterpart 4 possessed the highest cytotoxicity (50.11%). [ABSTRACT FROM AUTHOR]

Novel protein-based nanomaterials are gaining much interest in recent years due in large part to their more environment-friendly preparation schemes coupled with promising biological activities. Although nanoparticles synthesized from protein sources are not new, various researches are still continuously investigating other potential templates and sources of new protein-based materials. In this study, Ag nanoclusters capped with crude protein extracts from the sea anemone Heteractis magnifica ( H. magnifica) were prepared via one-pot, green synthesis, and subjected to preliminary biological activity testing. Fourier transform infrared spectroscopy (FTIR) analysis indicated successful capping of the nanoclusters, consistent with previous reports utilizing similar synthetic protocols, while scanning electron microscopy (SEM) revealed the presence of more aggregates on the surface of the prepared nanoclusters. Formation of the nanoclusters resulted in a slight to moderate antibacterial, but not antifungal, activity, although the material also showed a concentration-dependent hemolytic action. In contrast, the unmodified extract did not show any antimicrobial action while being more hemolytic as well. These results demonstrate the potential of these protein-capped Ag nanoclusters as antibacterial agents, although its unwanted hemolytic side effect will have to be reduced for it to have any therapeutic potential. [ABSTRACT FROM AUTHOR]

Two Pd(II) complexes, (HLCSS)Pd ( 1) and (KLCSS)Pd ( 2), were synthesized by stirring 2-(1-piperazinyl)ethanol (HLH)/ l-lysine (HL2H) monohydrate in methanol with KOH, CS and PdCl. Homobimetallic (Sn, Sn) products, PhSnLSn(Cl)Bu ( 3) and PhSnLSnBu ( 4) were produced by refluxing sodium but-2-ynedioate (NaL) with PhSnCl and BuSnCl or PhSnCl and BuSnCl in methanol. A heteronuclear (Sn,Pd) product, [(BuSn)LCSS]Pd ( 5) was synthesized by the reaction of 5-aminoisophthalic acid (HLH), KOH, CS, PdCl with BuSnCl. The products were characterized by elemental analysis, FT-IR, UV-Vis, H NMR and EIMS. A square planar geometry of Pd(II) and a penta-coordinated environment around Sn(IV) were verified in solid state. The complexes maintain their solid state geometries around Pd(II) even in solutions. Pd(II) complexes 1 and 2 exhibited a significant intercalating mode of binding with salmon sperm DNA. ALPs were inhibited in a concentration dependent manner. Sn(IV) complexes ( 3 and 4) were inactive against ALPs. Pd(II) complexes ( 1 and 2) were potent ALPs inhibitors, while the heteronuclear complex 5 was comparatively less active. Organotin(IV) products demonstrated significant antibacterial/ antifungal potential while Pd(II) products were inactive. The heteronuclear (Sn,Pd) product demonstrated moderate inhibition. Among all products, Pd(II) derivative 1 exhibited the highest hemolytic effect. [ABSTRACT FROM AUTHOR]

A study was carried out to determine the pathogenicity (hemolytic activity) on corals ( Turbinaria sp.) and sea bass ( Lates calcarifer) of Aeromonas hydrophila from water, sediment, and coral. Samples were collected from coastal water and coral reef areas. One hundred and sixty-two isolates were successfully isolated. Out of 162, 95 were from seawater, 49 from sediment, and 18 from coral. Sixteen isolates were picked and identified. Isolates were identified using a conventional biochemical test, the API 20NE kit, and 16S rRNA nucleotide sequences. Hemolytic activity was determined. Out of 16 isolates, 14 isolates were β-hemolytic and two isolates were non-hemolytic. Corals infected with A. hydrophila suffered bleaching. Similar effect was observed for both hemolytic and non-hemolytic isolates. Intramuscular injection of A. hydrophila into sea bass resulted in muscular bleeding and death. Higher infection rates were obtained from hemolytic compared to non-hemolytic strains of A. hydrophila isolates. [ABSTRACT FROM AUTHOR]

This study is designed to isolate and purify a novel anti-clotting protein component from the venom of Enhydrina schistosa, and explore its biochemical and biological activities. The active protein was purified from the venom of E. schistosa by ion-exchange chromatography using DEAE-cellulose. The venom protein was tested by various parameters such as, proteolytic, haemolytic, phospholipase and anti-coagulant activities. 80 % purity was obtained in the final stage of purification and the purity level of venom was revealed as a single protein band of about 44 kDa in SDS-polyacrylamide electrophoresis under reducing conditions. The results showed that the Potent hemolytic activity was observed against cow, goat, chicken and human (A, B and O positive) erythrocytes. Furthermore, the clotting assays showed that the venom of E. schistosa significantly prolonged in activated partial thromboplastin time, thrombin time, and prothrombin time. Venomous enzymes which hydrolyzed casein and gelatin substrate were found in this venom protein. Gelatinolytic activity was optimal at pH 5-9 and H NMR analysis of purified venom was the base line information for the structural determination. These results suggested that the E. schistosa venom holds good promise for the development of novel lead compounds for pharmacological applications in near future. [ABSTRACT FROM AUTHOR]

Herbal medicinal products have proven to be safe, economical and effective alternatives to synthetic chemical pharmaceuticals. The green tea plant ( Camellia sinensis) is of profound medicinal value due to the presence of potent bioactive constituents. The purpose of the present work is to investigate saponins from green tea seeds for potential use as anti-angiogenic, antimicrobial, and hemolytic agents. Green tea seed saponins were separated into six fractions by reverse phase HPLC. The presence of three aglycone chains in the saponins of each fraction was confirmed by acid hydrolysis. Anti-angiogenic activity was evaluated using saponin fractions at concentrations in the range of 2.5 ~ 25 μg/mL. Antimicrobial activity was evaluated by thin-layer chromatography (TLC) using E. coli; S. mutans, a zoonotic Salmonella species and the fungal strain, A. niger. Saponin fractions were more potent against E. coli (gram negative bacteria) than against S. mutans (gram positive bacteria) and strongly inhibited six strains of zoonotic Salmonella. Green tea saponins also showed potent anti-angiogenic effects. All saponin fractions exhibited hemolytic activity. Our results confirm that green tea saponins have antimicrobial, anti-angiogenic, and hemolytic activities; indicating their potential as natural pharmaceutical products. [ABSTRACT FROM AUTHOR]

Although anti-Jkb is a well-defined cause of severe acute or delayed hemolytic transfusion reactions, it is rarely associated with severe Hemolytic Disease of the Newborn (HDN), even with high antibody titer. To date, only 13 cases have been reported, so the possible reasons for that still remain unclear. Most of HDN due to anti-Jkb are mild-to-moderate, and usually have a good prognosis. A 41-years-old woman, who had a positive antibody screening test in her 13th week of pregnancy, was sent to the blood bank for study before an amniocentesis. Antibody identification and red blood cell (RBC) phenotyping of the patient and his husband were performed, plus arrays study in the amniotic fluid. An anti-Jkb was identified in the patient's serum with a titer of 1:1, and her RBC phenotype was O Rh(D) positive, C(+), c(+), E(−), e(+), K(−), Jka(+), Jkb(−). The RBC genotype of the fetus was B Rh(D) positive, Jka(+), Jkb(+). Antibody titer remained stable and the pregnancy was uneventful. At birth, there was no need of phototherapy or exchange transfusion for the newborn and her Jk(b+) typing result was confirmed in a cord blood sample. Although most of HDN cases due to anti-Jkb have a good outcome, monitoring antibody titer should be done to prevent fatal complications. Furthermore, antenatal antibody screening should be performed in every pregnant woman irrespective of her Rh(D) antigen status in order to detect red cell alloimmunization to other clinically significant blood group antigens. [ABSTRACT FROM AUTHOR]

The numerical simulation of the axial flow impeller blood pump NIVADIII is carried out by using a CFD multiphase flow model. The hydrodynamic performance of the pump and the flow field in the pump are analyzed, and the shear stress distribution is obtained. A hemolytic prediction model based on the shear stress is built based on the calculation results, and it can be used for quantitative predictions of the hemolytic behavior of a blood pump. Hemolysis tests in vitro were performed 6 times with fresh bovine blood. At each time, the flow of the pump NIVADIII is 5 L/min and the outflow tract pressure is 100 mmHg. According to the tests, the plasma free hemoglobin (FHB) content and the hematocrit (HCT) are measured after 0 s, 0.5 s, 1 s, 1.5 s, …4 s. At the end of each experiment Normal Index of Hemolysis (NIH) of NIVADIII is calculated. The average of NIH is 0.0055 g/100L, almost identical with that obtained from the hemolytic prediction model. This method can be applied in the selection stage of a blood pump. [ABSTRACT FROM AUTHOR]

Blooms of the toxic dinoflagellate, Karenia brevis, occur annually along the Gulf coast of Florida. Other species, like Karenia selliformis, are at times found in association. Hemolytic activity, the ability to lyse red blood cells, of two K. brevis clones (SP3 non-toxic (N-tox) and SP3 super toxic (S-tox)) from the Gulf of Mexico and a single clone of K. selliformis from New Zealand was investigated throughout a growth cycle. Activity is reported as effective concentration (EC50) values, the quantitative measure of hemolysis of human erythrocytes expressed as cell numbers. Both cells and media of K. selliformis cultures consistently produced potent levels of hemolysis (maximum EC50 = 4.88 × 103 cells) from inoculation until the population declined 35 days later. For SP3 N-tox and S-tox, no hemolytic activity was detectable until day 26 of sampling. The media of both SP3 N-tox and SP3 S-tox cultures consistently contained non-detectable or low levels of hemolysis compared to K. selliformis. Maximum EC50s for the SP3 clones were 1.80 × 106 and 1.97 × 106 cells, respectively. The experimental EC50 values observed represent ecologically relevant cell densities for K. selliformis, but not for the K. brevis clones. In addition, the hemolytic activity of gymnodimine A and various PbTx derivatives was examined in this study. Our findings indicate that the hemolytic capability of these dinoflagellates, especially K. selliformis, represents an additional component of toxicity aside from their already recognized toxins and that this activity may play a larger role than was previously considered. The purpose of this study was to extend the knowledge of the biology and toxicology of species within the genus Karenia. [ABSTRACT FROM AUTHOR]

Hemolysis is a major symptom of diseased eels infected by Edwardsiella tarda. The hemolysin gene of E. tarda strain ET16 was cloned into plasmid pSK and expressed in Escherichia coli. The mol. mass of the functional β-hemolysin was estimated to be approximately 34 kDa by gel filtration and by SDS-PAGE followed by in situ hemolysin activity analysis. The cloned fragment containing the β-hemolysin locus from E. tarda strain ET16 expressed in E. coli was estimated to be 5.3 kb in length; the deduced gene product was identical in mol. mass and properties to the extracellular products of E. tarda strain ET16. The presence of EcoRI and XbaI sites within the β-hemolysin gene of E. tarda was determined from the loss of hemolytic activity in subclones. Analysis of the DNA sequence of a 2,436-bp HaeIII- HindIII fragment that included EcoRI and XbaI sites revealed three ORFs organized as an operon that encoded three predicted polypeptides of 15,874, 7,055, and 34,804 Da. A 34-kDa polypeptide expressing hemolytic activity in cell lysates of the clone DH5α(pETH3E) is very likely the β-hemolysin encoded by the third ORF. The observation that hemolytic activity appeared in the culture medium of E. tarda, but not in that of E. coli strain DH5α(pETH3E) indicates the existence of a mechanism for transporting the hemolysin across the cell envelope in E. tarda that is different from that of E. coli. [ABSTRACT FROM AUTHOR]

Background: There were few report concerning anti-glycation and antioxidant activities of the minor amounts of components in curcuminoids, demethylcurcumin and tetrahydroxycurcumin, in vitro and in vivo. Results: The bovine serum albumin/galactose of non-enzymatic glycation models, radical-induced hemolysis, and oxygen radical absorbance capacity (ORAC) were studied in vitro, and the d-galactose-induced oxidative stress in BALB/c mice and then demethylcurcumin or tetrahydroxycurcumin interventions in vivo. The parameters of oxidative stress in plasma and brain extracts were determined among animal groups with or without both curcuminoids interventions. The demethylcurcumin and tetrahydroxycurcumin exhibited anti-glycation, anti-hemolysis, and ORAC activities, and showed much better and significant difference (P < 0.05) compared to those of curcumin in vitro. In animal experiments, the intervened two curcuminoids at both concentrations showed to lower serum malondialdehyde (MDA), brain MDA levels and iNOS protein expressions, and elevate serum ORAC activities, and showed difference (P < 0.05) compared to the galactose-induced control. Conclusion: The demethylcurcumin and tetrahydroxycurcumin showed potentials in developing functional foods for antioxidant-related purposes. [ABSTRACT FROM AUTHOR]

Background: The epidermal mucus of fish contains various bioactive compounds, which play a crucial role in the animal defense mechanisms. However, the mucus from giant mudskipper is not well characterized for its biochemical and pharmacological effects. This study for the first time analyzed the mucus extracts of this species for antimicrobial (against human pathogen) and hemolytic activities. Fourier-transform infrared spectrum analysis (FT-IR) and SDS-PAGE of mucus extracts were also carried out.Results: The protein content in Periophthalmodon schlosseri (Gobiidae: Oxudercine) mucus extracts was 0.66 ± 0.04 mg/ml. The mucus extracts of P. schlosseri showed antibacterial activity against all eight human pathogenic bacteria and four fungal strains tested in this study. The hemolytic activities against chicken and human blood cells were observed with maximum activity for dichloromethane extracts. The FT-IR spectrum of mucus extract of P. schlosseri showed the presence of functional groups, evident protein bands of various molecular weights ranging from 14 kDa to 97 kDa.Conclusion: The obtained results suggested that the mucus of this species has proteinaceous compounds responsible for antimicrobial and hemolytic activities. [ABSTRACT FROM AUTHOR]