Microbial Biosurfactant: Candida bombicola as a Potential Remediator of Environments Contaminated by Heavy Metals.

Industrial interest in surfactants of microbial origin has intensified recently due to the characteristics of these compounds, such as biodegradability and reduced toxicity, and their efficiency in removing heavy metals and hydrophobic organic compounds from soils and waters. The aim of this study was to produce a biosurfactant using Candida bombicola URM 3712 in a low-cost medium containing 5.0% molasses, 3.0% corn steep liquor and 2.5% residual frying oil for 144 h at 200 rmp. Measurements of engine oil tension and emulsification were made under extreme conditions of temperature (0 °C, 5 °C, 70 °C, 100 °C and 120 °C), pH (2-12) and NaCl concentrations (2-12), demonstrating the stability of the biosurfactant. The isolated biosurfactant was characterized as an anionic molecule with the ability to reduce the surface tension of water from 72 to 29 mN/m, with a critical micellar concentration of 0.5%. The biosurfactant had no toxic effect on vegetable seeds or on Eisenia fetida as a bioindicator. Applications in the removal of heavy metals from contaminated soils under dynamic conditions demonstrated the potential of the crude and isolated biosurfactant in the removal of Fe, Zn and Pb with percentages between 70 and 88%, with the highest removal of Pb being 48%. The highest percentage of removal was obtained using the cell-free metabolic liquid, which was able to remove 48, 71 and 88% of lead, zinc and iron from the soil, respectively. Tests in packed columns also confirmed the biosurfactant's ability to remove Fe, Zn and Pb between 40 and 65%. The removal kinetics demonstrated an increasing percentage, reaching removal of 50, 70 and 85% for Pb, Zn and Fe, respectively, reaching a greater removal efficiency at the end of 24 h. The biosurfactant was also able to significantly reduce the electrical conductivity of solutions containing heavy metals. The biosurfactant produced by Candida bombicola has potential as an adjuvant in industrial processes for remediating soils and effluents polluted by inorganic contaminants.

Novel production of biodispersant by Serratia marcescens UCP 1549 in solid-state fermentation and application for oil spill bioremediation.

Oil spills in aquatic ecosystems cause irreparable damage to marine life and the coastal populations of affected areas. In recent years, chemical dispersants have been extensively used to remedy these impacted ecosystems, although these agents have been increasingly restricted due to their toxic potential. In this context, biosurfactants are emerging as a promising alternative to chemical dispersants, which have some advantages including low toxicity, high biodegradability and good ecological acceptability. Thus, this study aimed to the production of biosurfactant by the bacteria Serratia marcescens UCP 1549 for application as biodispersant. The experiment was carried out using wheat bran as substrate in solid-state fermentation (SSF) as low-cost technology. Biosurfactant production was verified by the reduction of surface tension (28.4 mN/m) and interfacial tension (4.1 mN/m) with n-hexadecane. Also, promising result of emulsification (94%) with burned motor oil was obtained. Acid precipitation yielded 52.0 g/kg dry substrate of biosurfactant, that was identified as an anionic compound of a lipopeptide nature by the Zeta potential and FTIR spectrum, respectively. The biomolecule showed stability under extreme conditions of temperature, pH and salinity, as well as low toxicity against the microcrustacean Artemia salina. In addition, the biosurfactant demonstrated excellent properties to dispersing burned motor oil in water (ODA = 50.24 cm2) and to washing of marine stones (100% removal of burned motor oil). Therefore, these results confirm SSF as a sustainable technology for the production of biodispersant by S. marcescens UCP 1549, promising in the bioremediation of marine ecosystems impacted by petroderivatives.

High-Quality Draft Genome Sequence Resources of Eight Xylella fastidiosa Strains Isolated from Citrus, Coffee, Plum, and Hibiscus in South America.

Xylella fastidiosa subsp. pauca, once confined to South America and infecting mainly citrus and coffee plants, has been found to be associated with other hosts and in other geographic regions. We present high-quality draft genome sequences of X. fastidiosa subsp. pauca strains J1a12, B111, U24D, and XRB isolated from citrus plants in Brazil, strain Fb7 isolated from a citrus plant in Argentina and strains 3124, Pr8x, and Hib4 isolated, respectively, from coffee, plum, and hibiscus plants in Brazil. Sequencing was performed using Roche 454-GS FLX, MiSeq-Illumina or Pacific Biosciences platforms. These high-quality genome assemblies will be useful for further studies about the genomic diversity, evolution, and biology of X. fastidiosa.

Association of Sociodemographic Factors with Spirituality and Hope in Patients with Diabetic Foot Ulcers.

OBJECTIVE: To evaluate levels of spirituality and hope in patients with diabetic foot ulcers (DFUs) according to sociodemographic factors. DESIGN: This was a primary, prospective, descriptive, analytical, and clinical study. Questionnaires assessing sociodemographic and clinical characteristics of the patients, the Spirituality Self-rating Scale (SSRS), and the Herth Hope Index (HHI) were administered to all participants. SETTING: University-affiliated skilled nursing center and outpatient wound care clinic in Pouso Alegre, Brazil. PATIENTS: Fifty adult patients with DFUs participated in the study. Patients with ischemic diabetic foot and mixed ulcers were excluded from the study. MAIN RESULTS: On average, patients with DFUs had low levels of spirituality (mean SSRS score, 12.6) and low hope for cure (mean HHI, 16.5). Patients younger than 60 years reported significantly lower levels of spirituality (mean SSRS scores, 11.0), and those older than 70 years had significantly lower hope for cure (mean HHI, 12.5) than other age groups (P = .040). Level of spirituality was significantly lower among women (P = .015) and those living with an ulcer for more than 2 years, who also reported significantly lower hope for cure (P = .029) compared with patients having an ulcer for less than 2 years. CONCLUSION: On average, patients with DFUs, especially women and older adults, had a low sense of hope and spirituality. Except for gender, age, and ulcer duration, other sociodemographic and ulcer characteristics had no significant effect on the study population's spirituality and hope.

Association of sociodemographic factors with hope for cure, religiosity, and spirituality in patients with venous ulcers.

OBJECTIVE: The objective of the study was to evaluate the association of sociodemographic factors with hope for cure and levels of religiosity and spirituality in patients with venous leg ulcers (VLUs). DESIGN: This was a primary, prospective, descriptive, analytical, clinical, nonrandomized study. SETTING: The study was performed at a nursing care and education center of a university hospital in interior Minas Gerais, Brazil. PATIENTS: A convenience sample of 50 adult patients with VLUs and Doppler ankle-brachial index ranging from 0.8 to 1.0 participated in the study. Patients with mixed ulcers, arterial ulcers, and diabetic foot ulcers were excluded from the study. MAIN OUTCOME MEASURES: A questionnaire assessing sociodemographic and clinical characteristics of patients, the Spirituality Self-rating Scale (SSRS), and the Herth Hope Index (HHI) were administered to all patients. MAIN RESULTS: The mean SSRS score was 10.20, and the mean HHI was 25.5, corresponding to low levels of spirituality and moderate hope for cure, respectively. Patients aged between 50 and 59 years, men, nonsmokers, and those who were unemployed had the lowest mean SSRS scores. The lowest mean HHI values were reported by patients whose ulcers had exudate and odor, those aged 20 to 39 years, retired, and living with the wound for 1 year or less. Patients who had no religion or were not practicing a religion and those who considered living with an ulcer as a punishment reported low SSRS scores. CONCLUSION: The results showed that most patients with VLUs had low levels of spirituality, did not perceive divine intervention in their daily life or practice religious activities such as prayer, and had moderate hope for cure.

Inhibition of bacterial motility and spreading via release of cranberry derived materials from silicone substrates.

The motility of bacteria plays a key role in their colonization of surfaces during infection. Derivatives of cranberry fruit have been shown to interfere with bacterial motility. Herein, we report on the incorporation of cranberry derived materials (CDMs) into silicone substrates with the aim of impairing bacterial pathogen motility and spreading on the substrate surface. The release of CDMs from the silicone substrates when soaking in an aqueous medium was quantified for a period of 24h. Next, we showed that CDMs released from two silicone substrates remain bioactive as they downregulate the expression of the flagellin gene of two key uropathogens - Escherichia coli CFT073 and Proteus mirabilis HI4320. Furthermore, we demonstrate that CDM-modified silicone inhibits the swarming motility of P. mirabilis, an aggressive swarmer. The bioactive, CDM-modified substrates can find broad applications in the medical device and food industries where the impairment of bacterial colonization of surfaces is of paramount importance.

Metagenomic analysis of a tropical composting operation at the são paulo zoo park reveals diversity of biomass degradation functions and organisms.

Composting operations are a rich source for prospection of biomass degradation enzymes. We have analyzed the microbiomes of two composting samples collected in a facility inside the São Paulo Zoo Park, in Brazil. All organic waste produced in the park is processed in this facility, at a rate of four tons/day. Total DNA was extracted and sequenced with Roche/454 technology, generating about 3 million reads per sample. To our knowledge this work is the first report of a composting whole-microbial community using high-throughput sequencing and analysis. The phylogenetic profiles of the two microbiomes analyzed are quite different, with a clear dominance of members of the Lactobacillus genus in one of them. We found a general agreement of the distribution of functional categories in the Zoo compost metagenomes compared with seven selected public metagenomes of biomass deconstruction environments, indicating the potential for different bacterial communities to provide alternative mechanisms for the same functional purposes. Our results indicate that biomass degradation in this composting process, including deconstruction of recalcitrant lignocellulose, is fully performed by bacterial enzymes, most likely by members of the Clostridiales and Actinomycetales orders.