Efecto del pH y Sales Inorgánicas en la Degradación de Colorantes Industriales por Pleurotus Djamor

En la presente investigación se planteó el uso de la cepa Pd318 del hongo Pleurotus djamor como agente biorremediador, con el objetivo de evaluar su capacidad para degradar el colorante reactivo azul 19 (A19). Para ello se estudió la influencia que tienen cinco sales inorgánicas en el crecimiento y actividad lignolítica del hongo. Un cribado de sales inorgánicas en placa determinó que las sales CaCl2.2H2O y MnSO4.5H2O tienen mayor influencia en el desarrollo micelial y actividad lignolítica de la cepa. Ensayos de fermentación líquida (FEL) con diferentes combinaciones a distintas concentraciones de las sales de calcio y manganeso permitieron demostrar la capacidad de degradación del colorante azul 19 a los 7 días de fermentación líquida a temperatura ambiente y agitación constante. Los máximos porcentajes de degradación del colorante fueron obtenidos con las combinaciones A1B1 y A2B1 con 43,47% y 41,36%, respectivamente. Se observó que a un pH de 5 unidades se favorece la degradación del colorante. Los estudios en placa señalaron que la adición de sales de calcio y manganeso en 10 días de incubación favorecieron el desarrollo micelial y la actividad lignolítica de Pd318, mientras que en un sistema FEL de 7 días, únicamente la adición de manganeso influye favorablemente a la actividad lignolítica del hongo y en consecuencia a su capacidad de degradación de azul 19. Palabra clave: Colorante azul 19, degradación de colorantes, enzimas lignolíticas, Pleurotus djamor. Abstract In the present investigation, the use of the Pd318 strain of the Pleurotus djamor fungus as a bioremediation agent was proposed, with the aim of evaluating its ability to degrade reactive dye blue 19 (A19). For this, the influence of five inorganic salts on the growth and lignolytic activity of the fungus was studied. A plate screening of inorganic salts determined that the CaCl2.2H2O and MnSO4.5H2O salts have a greater influence on the mycelial development and lignolytic activity of the strain. Liquid fermentation tests (FEL) with different combinations at different concentrations of the calcium and manganese salts allowed to demonstrate the degradation capacity of the blue dye 19, after 7 days of liquid fermentation at room temperature and constant stirring, the maximum degradation percentages of the dye were obtained with the combinations A1B1 and A2B1 with 43.47% and 41.36% respectively. It was observed that at a pH of 5 units the degradation of the dye is favored. The plate studies indicated that the addition of calcium and manganese salts in 10 days of incubation, favored mycelial development and the lignolytic activity of Pd318, while in a 7 day FEL system, only the addition of manganese favorably influenced the lignolytic activity of the fungus and consequently its ability to break down blue 19. Keywords: Blue dye 19, dye degradation, lignolytic enzymes, Pleurotus djamor.

Synthesis and Diagnoses of New Metal Ions Complexes derived from Trimethoprim Schiff Bases

A New Schiff base (o-hydroxy benzylidene trimethoprim) derived from trimethoprim (known as a drug) was used as a ligand in this study, has been synthesized by condensation reaction from equal amounts of ortho hydroxybenzaldehyde and trimethoprim. This was then used for the preparation of new complexes by the reaction with Zinc and Manganese salts. The synthesized complexes were in the formula [M(OHTMP)2]X2 in the natural medium and [M(OHTMP)2-H] in basic medium (M=Zn, Mn, OHTMP = o-hydroxy benzylidene trimethoprim X= CH3COO, NO3, Cl2). The prepared complexes were diagnosed and characterized by employing FT-IR, 1H- NMR, CHN element analysis, molar conductivity, Molar refraction and flame atomic absorption techniques. Spectroscopic results proved the chelation behavior of this ligand. It coordinated to the metal ions as a tridentate ligand, via the imine nitrogen, azo methine, and phenolic oxygen atoms. According to the obtained results, octahedral geometry has been suggested for prepared complexes. The biological activities of the prepared ligand and complexes against Gram-positive bacteria (Staphylococcus aureus), Gram-negative bacteria (Escherichia coli, Pseudomonas aeruginosa, and Klebsiella spp.) have being conducted. Both, the ligand and complexes showed anti-bacterial activities, beter than that of the Trimethoprim.

Manganese salts function as potent adjuvants

Aluminum-containing adjuvants have been used for nearly 100 years to enhance immune responses in billions of doses of vaccines. To date, only a few adjuvants have been approved for use in humans, among which aluminum-containing adjuvants are the only ones widely used. However, the medical need for potent and safe adjuvants is currently continuously increasing, especially those triggering cellular immune responses for cytotoxic T lymphocyte activation, which are urgently needed for the development of efficient virus and cancer vaccines. Manganese is an essential micronutrient required for diverse biological activities, but its functions in immunity remain undefined. We previously reported that Mn2+ is important in the host defense against cytosolic dsDNA by facilitating cGAS-STING activation and that Mn2+ alone directly activates cGAS independent of dsDNA, leading to an unconventional catalytic synthesis of 2′3′-cGAMP. Herein, we found that Mn2+ strongly promoted immune responses by facilitating antigen uptake, presentation, and germinal center formation via both cGAS-STING and NLRP3 activation. Accordingly, a colloidal manganese salt (Mn jelly, MnJ) was formulated to act not only as an immune potentiator but also as a delivery system to stimulate humoral and cellular immune responses, inducing antibody production and CD4+/CD8+ T-cell proliferation and activation by either intramuscular or intranasal immunization. When administered intranasally, MnJ also worked as a mucosal adjuvant, inducing high levels of secretory IgA. MnJ showed good adjuvant effects for all tested antigens, including T cell-dependent and T cell-independent antigens, such as bacterial capsular polysaccharides, thus indicating that it is a promising adjuvant candidate.

Comparative Study of the Photocatalytic Hydrogen Evolution over Cd1−xMnxS and CdS-β-Mn3O4-MnOOH Photocatalysts under Visible Light

A series of solid solutions of cadmium and manganese sulfides, Cd1−xMnxS (x = 0–0.35), and composite photocatalysts, CdS-β-Mn3O4-MnOOH, were synthesized by precipitation with sodium sulfide from soluble cadmium and manganese salts with further hydrothermal treatment at 120 °C. The obtained photocatalysts were studied by the X-ray diffraction method (XRD), UV-vis diffuse reflectance spectroscopy, transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), and N2 low temperature adsorption. The photocatalysts were tested in hydrogen production using a Na2S/Na2SO3 aqueous solution under visible light (λ = 450 nm). It was shown for the first time that both kinds of photocatalysts possess high activity in hydrogen evolution under visible light. The solid solution Cd0.65Mn0.35S has an enhanced photocatalytic activity due to its valence and conduction band position tuning, whereas the CdS-β-Mn3O4-MnOOH (40–60 at% Mn) samples were active due to ternary heterojunction formation. Further, the composite CdS-β-Mn3O4-MnOOH photocatalyst had much higher stability in comparison to the Cd0.65Mn0.35S solid solution. The highest activity was 600 mmol g−1 h−1, and apparent quantum efficiency of 2.9% (λ = 450 nm) was possessed by the sample of CdS-β-Mn3O4-MnOOH (40 at% Mn).

ASSESSING THE QUALITY OF HOMOGENEITY OF PET FOOD USING FERROMAGNETIC MICROTRACERS

Obtaining highly homogeneous mixtures is an urgent task in many areas of feed production, as it is associated with the need for even distribution of particularly important and valuable components. Manufacturers of animal feed are using several different methods for performing homogeneity studies to check their mixer performance. This paper is devoted to the use of nontraditional markers such as ferromagnetic Microtracers to evaluate the homogeneity of the final feed. Microtracers have successfully been used in a mixer testing program in the USA since 1985 and in Europe since 2006. They represent a major improvement over traditional analytical procedures for evaluation of mixer performance involving the use of cobalt or manganese salts. The authors described the quantitative results of determination and identification of Microtracers in two sets of 20 samples of pet food manufactured by Kormotech LLC with using a proprietary Rotary Detector procedure developed by Micro-Tracers Inc (San Francisco, California). It was shown that analysis of 150 g samples at level of Microtracer addition of 20 g per metric ton of pet food allowed a magnetic retrieval of the number of ferromagnetic particles from 61 to 101 which was sufficient for application of Poisson and Chi-squared statistics. The obtained results from two tests performed with different time of mixing were interpreted in accordance with the requirements of the GMP + BA2 standard. It was determined that mixing within 3 min leads to the marginal mixing with the calculated probability value of 1.12%. The prolonged mixing within 4 min leads to complete mixing with the calculated probability value of 5.93%. The use of ferromagnetic Microtracers in a mixer testing program is justified for such tasks as comparison of mixers with each other, as well as identifying the changes in the technical characteristics of the mixers and their performance occurring during their exploitation. In addition, using microtracers can quickly determine the quality of the mixing equipment when it is purchased.

Growth studies of Leuconostoc mesenteroides on corn biomass based substrates

Leuconostoc mesenteroides is a well-known industrial producer of extracellular bacterial polysaccharide dextran. The main raw material for industrial cultivation of these microorganisms is molasses. Sucrose of molasses is the main source of carbon and energy for bacteria, as well as a precursor of dextran biosynthesis. It is known that the bacteria of the genus Leuconostoc are heterofermentative microorganisms and are capable to utilize various carbohydrates. The purpose of this study was to evaluate the of the corn biomass based mediumon the yield of bacterial biomass and the concentration of the extracellular polysaccharide.The hydrolyzate is a product of chemo-enzymatic treatment of plant lignocellulosic corn biomass and contains such monosaccharides as glucose, arabinose and xylose. The parameters of the composition of the medium were the concentration of hydrolyzate carbohydrates in the form of reducing substances (RS), the concentration of nitrogen (protein and non-protein), sucrose and the presence of minerals. The parameters of the cultivation process are pH and temperature. According to experimental data, the maximum yield of bacterial biomass (9.3 and 8.5%) were achieved on combined media with a sucrose content of 0.2% and a sodium salt (sodium phosphate), respectively. The highest specific growth rates of microorganisms (0.0840 and 0.0746) are demonstrated on a combined medium with a content of 0.15 and 0.3% inorganic nitrogen, respectively. The highest concentrations of extracellular polysaccharides (0.840 and 0.583%) are formed when magnesium and manganese salts are present in the nutrient medium. The optimal pH level for effective growth s is about 7, and the temperature in the range of 30-35 ° C.

Water oxidation by simple manganese salts in the presence of cerium(iv) ammonium nitrate: towards a complete picture

For the first time, using some methods, we showed that under the water-oxidation conditions and in the presence of cerium(iv) ammonium nitrate, some manganese salts are converted to Mn oxide.