Cytotoxicity, structural, conformational, and techno-functional properties of α-lactalbumin nanostructured aggregates.

Protein nanostructures can be used in food applications to improve the techno-functional properties of a food formulation. This study aims to find the best conditions for the production and conformational change of α-lactalbumin nanostructured aggregates. The criteria to determine the best operating conditions to produce α-lactalbumin nanostructured aggregates were intensification of foaming and emulsification, techno-functional proprieties, cytotoxic, and antibacterial activity of nanostructures compared with native α-lactalbumin. Conformational alterations occurred in the α-helix and sheet-ß protein structures. The size obtained by dynamic light scattering was 163.84 nm with a polydispersity index of 0.29. The nano protein improved the techno-functional property compared to the native protein. Additionally, nanostructures had no cytotoxic effect and were innocuous to bacterial activity. Thus, this study presents the best conditions to produce α-lactalbumin nanostructured aggregates with improved properties that allow new food industry applications.

Rapid green synthesis of silver nano particles from Ziziphus mauritianaand antibacterial activity against human pathogens

A novel green source Ziziphus mauritiana fresh young leaves was opted to synthesize silver nanoparticles and analyze its antibacterial activity. The bioactive compounds present in the plant extracts reduced silver ions to NPs, indicated by change in colorfrom red to dark brown. In this study, we have successfully synthesized nanoparticles using Z.mauritiana aqueous leaf extract as a reducing agent and the reaction process of synthesized nanoparticles was monitored by UV-Vis spectroscopy. The UV-Vis absorption peak showed maximum adsorption at 420 nm confirmed the silver nanoparticles synthesis. Further characterization was carried out by FTIR and the results recorded a downward shift of absorption the bands between 400 to 4000 cm-1indicates the formationof silver nanoparticles. Finally, the present research was exploited to study the antibacterial activity of synthesized nanoparticles produced Z.mauritiana was studied using different pathogenic bacteria such as Salmonellasp., Proteus sp., Bacillus sp., Klebsiella pneumonia and E.colifrom the well diffusion results, the synthesized silver nanoparticles displayed the best antibacterial property as compared to the antibiotic has been reported in this paper. To the best of our knowledge, this is the first report that the Z.mauritiana aqueous extract facilitate the synthesis of silver nanoparticles and also exhibits antibacterial activity.

Antibacterial Activity of 7-Epiclusianone and Its Novel Copper Metal Complex on Streptococcus spp. Isolated from Bovine Mastitis and Their Cytotoxicity in MAC-T Cells.

Mastitis is an inflammation of mammary gland parenchyma that adversely affects bovine health and dairy production worldwide despite significant efforts to eradicate it. The aim of this work was to characterize the antimicrobial activity of 7-epiclusianone (7-epi), a compound extracted from the Rheedia brasiliensis fruit, its complex with copper against Streptococcus spp. isolated from bovine mastitis, and to assess their cytotoxicity to bovine mammary alveolar cells (MAC-T). The complex 7-epiclusianone-Cu (7-epi-Cu) was an amorphous green solid with optical activity. Its vibrational spectrum in the infrared region showed absorption bands in the high-frequency region, as well as bands that can be attributed to the unconjugated and conjugated stretching of the free ligand. The complex was anhydrous. One of the tested bacterial strains was not sensitive to the compounds, while the other three had MIC values of 7.8 µg mL-1 and minimum bactericidal concentration (MBC) values between 15.6 and 31.3 µg mL-1. These two compounds are bacteriostatic, did not cause damage to the cell wall and, at sub-inhibitory concentrations, did not induce bacterial adhesion. The compounds were not cytotoxic. Based on these results, 7-epi and 7-epi-Cu exhibited desirable antimicrobial properties and could potentially be used in bovine mastitis treatment.

Investigation of Structural, Morphological, Magnetic Properties and Biomedical applications of Cu2+ Substituted Uncoated Cobalt Ferrite Nanoparticles

ABSTRACT In the present work, Cu2+ substituted cobalt ferrite (Co1-xCuxFe2O4, x = 0, 0.3, 0.5, 0.7 and 1) magnetic nanopowders were synthesized via chemical co-precipitation method. The prepared powders were investigated by various characterization methods such as X-ray diffraction analysis (XRD), scanning electron microscope analysis (SEM), vibrating sample magnetometer analysis (VSM) and fourier transform infrared spectroscopy analysis (FTIR). The XRD analysis reveals that the synthesized nanopowders possess single phase centred cubic spinel structure. The average crystallite size of the particles ranging from 27-49 nm was calculated by using Debye-scherrer formula. Magnetic properties of the synthesized magnetic nanoparticles are studied by using VSM. The VSM results shows the magnetic properties such as coercivity, magnetic retentivity decreases with increase in copper substitution whereas the saturation magnetization shows increment and decrement in accordance with Cu2+ substitution in cobalt ferrite nanoparticles. SEM analysis reveals the morphology of synthesized magnetic nanoparticles. FTIR spectra of Cu2+ substituted cobalt ferrite magnetic nanoparticles were recorded in the frequency range 4000-400cm-1. The spectrum shows the presence of water adsorption and metal oxygen bonds. The adhesion nature of Cu2+ substituted cobalt ferrite magnetic nanoparticles with bacteria in reviewed results indicates that the synthesized nanoparticles could be used in biotechnology and biomedical applications.

Activities of different types of Thai honey on pathogenic bacteria causing skin diseases, tyrosinase enzyme and generating free radicals

BACKGROUND: Honey is a natural product obtained from the nectar that is collected from flowers by bees. It has several properties, including those of being food and supplementary diet, and it can be used in cosmetic products. Honey imparts pharmaceutical properties since it has antibacterial and antioxidant activities. The antibacterial and antioxidant activities of Thai honey were investigated in this study. RESULTS: The honey from longan flower (source No. 1) gave the highest activity on MRSA when compared to the other types of honey, with a minimum inhibitory concentration of 12.5% (v/v) and minimum bactericidal concentration of 25% (v/v). Moreover, it was found that MRSA isolate 49 and S. aureus were completely inhibited by the 50% (v/v) longan honey (source No. 1) at 8 and 20 hours of treatment, respectively. Furthermore, it was observed that the honey from coffee pollen (source No. 4) showed the highest phenolic and flavonoid compounds by 734.76 mg gallic/kg of honey and 178.31 mg quercetin/kg of honey, respectively. The antioxidant activity of the honey obtained from coffee pollen was also found to be the highest, when investigated using FRAP and DPPH assay, with 1781.77 mg FeSO4•7H2O/kg of honey and 86.20 mg gallic/kg of honey, respectively. Additionally, inhibition of tyrosinase enzyme was found that honey from coffee flower showed highest inhibition by 63.46%. CONCLUSIONS: Honey demonstrates tremendous potential as a useful source that provides anti-free radicals, anti-tyrosinase and anti-bacterial activity against pathogenic bacteria causing skin diseases.

Antibacterial properties of auraptene and oxyprenylated naturally occurring benzoic and cinnamic acids / Propiedades antibacterianas del auraptene y acidos benzoicos y cinámicos oxi-prenilados naturales

The in vitro anti-bacterial activity of auraptene and four prenyloxycinnamic and benzoic acids was evaluated against a panel of three bacterial strain. All compounds were shown to be active as inhibitory agents of the growth of Staphylococcus aureus.

La actividad antibacteriana in vitro del auraptene y de cuatro ácidos preniloxycinámicos y benzoicos ha sido evaluada sobre un grupo de tres distintas cepas bacterianas. Todos los compuestos mostraron ser activos como agentes inhibitorios del crecimiento del Staphylococcus Aureus.

Contaminação de resinas compostas em consultórios odontológicos / Contamination of composite resin at dentistry offices

Este trabalho avaliou o nível de contaminação de resinascompostas utilizadas em consultórios odontológicos do DistritoFederal. Um total de cinqüenta e cinco amostras foram coletadasde resinas compostas, de tubetes em uso nestes locais. Essasforam processadas no laboratório de Microbiologia. Os resultadosrevelaram que 80% delas se encontravam contaminadaspor Staphylococcus coagulase-negativo (47,2%), Staphylococcuscoagulase-negativo mais Bacillus sp (16,3%), Bacillus sp (12,7%)e Aspergilus sp (3,6%). Não houve crescimento microbiano nogrupo controle selecionado (0% de contaminação). A pesquisadestaca a necessidade de adoção de medidas de biossegurançaespecíficas na manipulação das resinas compostas por profissionaise equipe odontológica, a fim de tornar sua utilização clínicasegura.

The purpose of this study was to evaluate the level of contaminationof composite resins at dentistry officies in DistritoFederal. Fifty five samples of compositive resin were colectedon the tubes in use at this places. These samples were processedat the Microbiology laboratory. The results revealed that 80% ofthe samples were contaminated, in which accused the presenceof Stafilococcus coagulase-negativo (47,2%), Stafilococcus coagulase-negativo associated with Bacillus sp.(16,3%), Bacillussp (12,7%) and Aspergilus sp (3,6%). The control group selecteddid not show a microbiology growth (0% of contamination). Thedata of this work show the necessity to adopt specific biossecurityrules in the manipulation of composite resins by dentistsand his staff to promote its clinical utilization with safety.