Biosorption of heavy metals from phosphate-processing effluent by Serratia rubidaea NCTC12971 immobilized in Ca-alginate beads / Biosorción de metales pesados a partir de efluentes de procesamiento de fosfatos por Serratia rubidaea NCTC12971 inmovilizados en cuentas de Ca-alginato

In this study, the biosorption ability of various potentially toxic elements from phosphate-processing effluent (PPE) using the indigenous bacterium Serratia rubidaea NCTC12971 immobilized in Ca-alginate beads was investigated. The experimental data analyzed by the Langmuir isotherm revealed that the optimum dose of 2 g·100 ml−1 of immobilized S. rubidaea NCTC12971 at pH 7 and a contact time of 48 h allowed the removal of 92.07%, 98.05%, 95.57%, and 88.39% of lead (Pb (II)), cadmium (Cd (II)), copper (Cu (II)), and zinc (Zn (II)), respectively. Moreover, under the Langmuir isotherm, the maximum single-layer adsorption capacity (qmax) of the biosorbent was estimated to 32.14 mg g−1, 45.87 mg g−1, 0.06 mg g−1, and 3.01 mg g−1 for Pb (II), Cd (II), Cu (II), and Zn (II), respectively, under the stated conditions. Alternatively, the regeneration and reuse of the Ca-alginate beads was evaluated. Indeed, after four consecutive adsorption–desorption cycles, there was no significant loss in the biosorption capacity. The effectiveness of the bacterial biosorption as treatment process was evaluated by assessing the phytotoxicity of the treated effluent (TE) on Medicago sativa and Lactuca sativa seed germination and their root elongation. Results exhibited a significant toxicity removal expressed by a notable increase in the germination indices (GI), which reach 80% and 70%, respectively, for Medicago sativa and Lactuca sativa compared to the GI values of 46.6% and 16.6% of the same species in presence of the untreated effluent (PPE).(AU)

Antifungal compound from marine Serratia marcescens BKACT and its potential activity against Fusarium sp / Compuesto antifúngico de Serratia marcescens marina BKACT y su potencial actividad contra Fusarium sp

Ecofriendly biocontrol agents to control pathogenic fungi are in demand globally. The present study evaluated the antifungal potentials of marine bacteria Serratia marcescens BKACT against eight different Fusarium species. A highest 75.5 ± 0.80% of mycelial inhibition was observed against Fusarium foetens NCIM 1330. Structural characterization of the purified compound was analyzed by GC–MS and NMR techniques; based on the analysis, it is confirmed as 2, 4-di-tert butyl phenol (2, 4-DTBP) with chemical structure C14H22O. At 0.53 mM concentration, purified compound inhibited complete spore germination of F. foetens NCIM 1330. In vitro assay showed complete inhibition of F. foetens NCIM 1330 on the wheat seeds. Tested concentration does not show any toxic effect on germination of the seeds. By this study, we conclude that, 2, 4-DTBP is a suitable candidate to be used as biocontrol agent against Fusarium infection.(AU)

Bacteria contamination analysis on the hands and bowls of meatball cart vendors: an observational descriptive study

Objective: To describe the presence of bacteria at the seller's hand of meatball vendors and cart meatball bowls. Method: This is a descriptive study with an observational approach. Thirty mobile meatball vendors were recruited as participants. Therefore, the bacterias from bowls and hands were taken by swab sampling. The number of bacterias were obtained using total plate count method by means of nutrient agar. Bacteria types were identified using Gram staining method and bacteria assay. Results: The hands and bowls swab samples were positive for Gram-positive and Gram-negative bacteria in all cases. These microorganisms include Acinetobacter calcoaceticus, Klebsiella sp., Alcaligenes faecalis, Enterobacter aglomereus, Pseudomonas aeruginosa, Enterobacter aerogenes, Enterobacter cloacae, and Staphylococcus saprophyticus, Serratia rubidaea, Yersinia enterocolitica, E. aerogenes, and Staphylococcus epidermidis. Conclusions: Some types of bacterias were present in cart meatball bowls and the sellers’ hands. This phenomenon is affiliated with the emergence of food-borne diseases for the consumers. (AU)

Colonización por Serratia fonticola de una úlcera vascular venosa en el miembro inferior izquierdo / Colonization by Serratia fonticola of vascular-venous ulcer in lower left limb

Presentamos el caso de una paciente afectada de insuficiencia vascular venosa periférica derivada desde la consulta de enfermería por padecer una úlcera vascular de meses de evolución. Se realiza un cultivo del exudado de dicha úlcera, que muestra una colonización por la enterobacteria Serratia fonticola. Al tratar esta infección con ciprofloxacino, la paciente evoluciona favorablemente; al cabo de tres meses la úlcera se ha curado dejando una cicatriz queloidea (AU)

We present the case of a female patient with peripheral venous and vascular insufficiency, referred from the nursing consultation due to a vascular ulcer of several months’ evolution. Exudate was collected and a culture made, with the finding of colonization by the enterobacterium Serratia fonticola. This infection was treated with ciprofloxacin, its evolution being favorable. The patient was cured after three months, a queloid scar remaining (AU)

Exposición laboral a hongos y bacterias ambientales en una planta de selección de residuos de envases / Occupational exposure to airborne fungi and bacteria in a sorting source-separated packages household waste plant

Distintos estudios han mostrado una asociación entre la actividad laboral enplantas de tratamiento de residuos y la aparición de distintos síntomas en lostrabajadores, como irritación de piel, ojos y membranas mucosas, trastornosgastrointestinales y respiratorios, y el síndrome tóxico por polvo orgánico.Estos síntomas se han asociado con la exposición a bioaerosoles.El objetivo de este trabajo es determinar la exposición laboral a agentesbiológicos en una planta de selección de envases procedentes exclusivamentede la recogida selectiva de residuos sólidos urbanos.Las muestras ambientales se obtuvieron por el método de impactación enplaca con el equipo M Air T de Millipore. Se determinó la concentración dehongos totales, bacterias totales y bacterias gramnegativas y, en cada caso,se identificaron los géneros fúngicos y bacterianos obtenidos.Los microorganismos mayoritarios han sido los hongos, con recuentossuperiores a 12.000 ufc/m3, y las bacterias gramnegativas, que se handeterminado en concentraciones ambientales entre 1.395 y 5.280 ufc/m3.En ambos casos, estas concentraciones han sido muy superiores a lashalladas en la muestra de referencia obtenida en el exterior de la planta.Entre los hongos, los géneros mayoritarios han sido Penicillium yCladosporium, mientras que entre las bacterias gramnegativas se identificaronlos géneros Escherichia, Enterobacter, Klebsiella y Serratia.En conclusión, los trabajadores de una planta de selección de envasesprocedentes de la recogida selectiva de residuos sólidos urbanos puedenestar expuestos a agentes biológicos, especialmente en forma de hongos ybacterias gramnegativas(AU)

Several studies have showed an association between the work in wastetreatment plants and occupational health problems such as irritation of skin,eyes and mucous membranes, pulmonary diseases, gastrointestinal problemsand symptoms of organic dust toxic syndrome (ODTS). These symptoms havebeen related to bioaerosol exposure.The aim of this study was to investigate the occupational exposure tobiological agents in a plant sorting source-separated packages (plasticsmaterials, ferric and non-ferric metals) household waste.Airborne samples were colleted with M Air T Millipore sampler.The concentration of total fungi and bacteria and gram-negative bacteria weredetermined and the most abundant genera were identified.The results shown that the predominant airborne microorganisms were fungi,with counts greater than 12,000 cfu/m3 and gram-negative bacteria, with aenvironmental concentration between 1,395 and 5,280 cfu/m3. In both cases,these concentrations were higher than levels obtained outside of the sortingplant.Among the fungi, the predominant genera were Penicillium and Cladosporium,whereas the predominant genera of gram-negative bacteria were Escherichia,Enterobacter, Klebsiella and Serratia.The present study shows that the workers at sorting source-separatedpackages (plastics materials, ferric and non-ferric metals) domestic wasteplant may be exposed to airborne biological agents, especially fungi andgram-negative bacteria(AU)