Comprehensive adsorption and spectroscopic studies on the interaction of magnetic biochar from black wattle sawdust with beta-blocker metoprolol.

The rise of contaminants of emerging concern in water-resources due to human activities has driven research toward wastewater treatment, specifically adsorption. The utilization of woody biomass for biochar production in adsorption has shown promise due to its high availability. This study shows the preparation of magnetic biochars (MB) from waste black wattle sawdust, utilizing ZnCl2 and NiCl2 (proportions: 1:0.5:0.5 = MB-0.5 and 1:1:1 = MB-1) as activating and magnetic agents. Synthesized via microwave-assisted-pyrolysis, MB boasts a high surface area (up to 765 m2.g-1) and functional groups, enhancing metoprolol medicine adsorption. Nonlinear kinetic and isothermal models were tested; the Avrami fractional-order kinetic model and Liu's isothermal model provided the best fits for experimental data. Thermodynamics and spectroscopic studies revealed spontaneous and exothermic adsorption processes, with physisorption magnitude and dominance of hydrogen-bond and π-π-interactions. MB can be easily extracted from an aqueous medium using magnetic fields, while adsorption capacity could be regenerated through green solvent elution.

Influence of Mycoplasma bovis infection on milk production and quality of Holstein dairy cows.

We wished to determine if Mycoplasma bovis infection can negatively impact milk quality and production in Holstein dairy cows. For this Research Communication, milk samples (271) from Holstein cows from 3 herds were screened for M. bovis by real-time PCR. Positive (n = 21) and negative animals (n = 21) were matched by herd, age, lactations and days in milk (DIM). Pairs were evaluated in 7 stages of lactation: D1-50, D51-100, D101-150, D151-200, D201-250, D251-300, and D ≥ 301. A mixed model was used to assess the effect of groups (M. bovis+ × M.bovis-), time (lactation) and groups × time interaction. Cows positive for M. bovis had lower average milk production per day and high somatic cells count (SCC).

Adsorption of amoxicillin onto high surface area-activated carbons based on olive biomass: kinetic and equilibrium studies.

This study presents the extraction of antibiotic amoxicillin (AMX) from aqueous solution employing activated carbons (AC) from olive biomass (OB). Two AC were prepared using ZnCl2 (activator agent), and a conventional muffle furnace (ACF) or microwave oven (ACMW). The structure, morphology, and textural properties from both AC were analyzed by scanning electron microscope (SEM), pH of point-zero-charge (pHPZC), infrared spectroscopy (FTIR), and N2 adsorption/desorption isotherms. AC with mesoporous structures rich in oxygenated groups and high specific area (as high as 1742 m2 g-1) were helpful for the efficient and fast adsorption of AMX. The Avrami kinetic nonlinear equation showed the best fitting for the empirical data when related to the pseudo-1st and pseudo-2nd order. The isothermal experimental data followed the Liu nonlinear model, displaying at 25 °C the maximum sorption capacity of 237.02 and 166.96 mg g-1 for the ACF and ACMW, respectively. An adsorption test with synthetic hospital effluent was carried out to evaluate the possibility of applying both adsorbents in wastewater purification. The purification efficiency was up to 94.4% and 91.96% for ACF and ACMW, respectively. Therefore, the AC obtained from OB (containing a mixture of seed, pulp, and olive peel) has a high potential for application in removing emerging contaminants from the wastewater.

Microbiological and molecular detection of Mycoplasma bovis in milk samples from bovine clinical mastitis / Detecção microbiológica e molecular de Mycoplasma bovis em amostras de leite oriundas de mastite clínica bovina

The genus Mycoplasma includes more than 200 bacterial species that cause disease in animals. It is responsible for causing mastitis in bovines and may be related to other manifestations, such as arthritis and pneumonia in calves and heifers. The present study aimed to detect Mycoplasma bovis isolated from milk samples of bovine clinical mastitis, and to compare the isolation rates in two culture media: Hayflick and SP4. An initial screening was performed in order to detect the presence of the class Mollicutes in 1166 milk samples from clinical mastitis by the conventional Polymerase Chain Reaction (PCR) technique. According to the 1166 milk samples evaluated, 8.6% (100/1166) were positive to class Mollicutes. Regarding molecular analyses, 1.1% (13/1166) of conventional PCR for positive M. bovis was obtained and 0.9% (11/1166) in real-time PCR. The results of the microbiological culture of the 100 samples previously screened demonstrated that 6% (6/100) of colony growth have been developed when using the Hayflick medium, and 11% (11/100) when using the SP4 medium (including the positive on Hayflick medium). Concerning the 11 isolates obtained in the microbiological culture, conventional PCR confirmed M. bovis in nine of them, and two cultures were negative. In the phylogenetic analysis of the isolates, all of them were grouped in M. bovis and M. agalactiae clusters. The results confirmed the importance of the presence of M. bovis in the etiology of bovine clinical mastitis and reinforced the need for further studies to elucidate other Mycoplasma species that may be involved in bovine clinical mastitis in Brazil.(AU)

O gênero Mycoplasma inclui mais de 200 espécies que causam doenças nos animais. É responsável por quadros de mastite em bovinos, podendo também estar relacionado à outras manifestações como artrite e pneumonia em bezerros e novilhas. O presente estudo objetivou a detecção de Mycoplasma bovis isolados a partir de amostras de leite de mastite clínica bovina, bem como, a comparação da taxa de isolamento em dois meios de cultura: Hayflick e SP4. Para efeito de triagem amostral, foram avaliadas quanto à presença da classe Mollicutes 1166 amostras de leite de casos de mastite clínica pela técnica de PCR convencional. Das 1166 amostras de leite avaliadas, 8,6% (100/1166) foram positivas à classe. Nas análises moleculares, obteve-se 1,1% (13/1166) de positividade para Mycoplasma bovis na PCR convencional e 0,9% (11/1166) na PCR em tempo real. Os resultados do cultivo microbiológico das 100 amostras triadas previamente demonstraram 6% (6/100) de crescimento de colônias ao se utilizar o meio Hayflick e 11% (11/100) ao se utilizar o meio SP4 (incluindo as positivas ao primeiro). A partir dos 11 isolados obtidos no cultivo microbiológico, a PCR convencional confirmou Mycoplasma bovis em nove deles, e dois foram negativos para o agente. Na análise filogenética dos isolados, todos agruparam no cluster Mycoplasma bovis e Mycoplasma agalactiae. Frente aos resultados, ressalta-se a importância da presença de Mycoplasma bovis na etiologia da mastite clínica bovina e reforça a necessidade de estudos mais aprofundados para a elucidação de outras espécies de micoplasmas que possam estar envolvidas na mastite bovina.(AU)