Healthy lifestyle and essential metals attenuated association of polycyclic aromatic hydrocarbons with heart rate variability in coke oven workers.

Whether adopting healthy lifestyles and maintaining moderate levels of essential metals could attenuate the reduction of heart rate variability (HRV) related to polycyclic aromatic hydrocarbons (PAHs) exposure are largely unknown. In this study, we measured urinary metals and PAHs as well as HRV, and constructed a healthy lifestyle score in 1267 coke oven workers. Linear regression models were used to explore the association of healthy lifestyle score and essential metals with HRV, and interaction analysis was performed to investigate the potential interaction between healthy lifestyle score, essential metals, and PAHs on HRV. Mean age of the participants was 41.9 years (84.5% male). Per one point higher healthy lifestyle score was associated with a 2.5% (95% CI, 1.0%-3.9%) higher standard deviation of all normal to normal intervals (SDNN), 2.1% (95% CI, 0.5%-3.6%) higher root mean square of successive differences in adjacent NN intervals (r-MSSD), 4.3% (95% CI, 0.4%-8.2%) higher low frequency, 4.4% (95% CI, 0.2%-8.5%) higher high frequency, and 4.4% (95% CI, 1.2%-7.6%) higher total power, respectively. Urinary level of chromium was positively associated with HRV indices, with the corresponding ß (95% CI) (%) was 5.17 (2.84, 7.50) for SDNN, 4.29 (1.74, 6.84) for r-MSSD, 12.26 (6.08, 18.45) for low frequency, 12.61 (5.87, 19.36) for high frequency, and 11.31 (6.19, 16.43) for total power. Additionally, a significant interaction was found between healthy lifestyle score and urinary total hydroxynaphthalene on SDNN (Pinteraction = 0.04), and higher level of urinary chromium could attenuate the adverse effect of total hydroxynaphthalene level on HRV (all Pinteraction <0.05). Findings of our study suggest adopting healthy lifestyle and maintaining a relatively high level of chromium might attenuate the reduction of HRV related to total hydroxynaphthalene exposure.

Characterization and finding the origin of off-flavor compounds in Nile tilapia cultured in net cages in hydroelectric reservoirs, São Paulo State, Brazil.

An increasing demand for fish products has led to an intensive aquaculture production in Brazil, and cultivation of fish constituted 860 × 103 tons in 2022, contributing to the 87% of total fish consumption. Nile tilapia constitutes almost half of the aquaculture production, and most tilapia farms use floating net cages. One of the major constraints of intensive fish production is production of off-flavors. Release of nutrients by the fish leads to deterioration of the water quality and stimulates growth of microorganisms, also including off-flavor producing species. The objective of this study was to determine levels of taste and odor compounds (geosmin, 2-MIB and a selection of volatile compounds) and their impact on the flavor quality of Nile tilapia produced in net cages in reservoirs in São Paulo State, Brazil. GC-MS analysis of fish and water from six different farms showed concentrations of geosmin in the water from 1 to 8 ng/L, while geosmin in fish flesh ranged from 40 to 750 ng/kg. The level of 2-MIB in water was 2 to 25 ng/L, and 0 to 800 ng/kg fish. The GC-MS analysis also revealed presence of more than 100 volatile organic compounds in the fish flesh, consisting of aldehydes, alcohols, benzene derivatives, hydrocarbons, ketones and few other compounds. Geosmin and 2-MIB related flavor notes were detected in all fish by a sensory panel, and a high correlation between the chemical and sensory analyses was found. The potential impact of the volatile organic compounds on the fish flavor is discussed. Analysis of the water quality in the reservoirs indicated that levels of geosmin and 2-MIB levels were highly influenced by the nutrient levels in the water.

Biomonitoring of polycyclic aromatic hydrocarbons in Brazilian pregnant women: Urinary levels and health risk assessment.

Over the years, humans have been continuously exposed to several compounds directly generated by industrial processes and/or present in consumed products. Polycyclic aromatic hydrocarbons (PAHs) are legacy pollutants ubiquitous in the environment and represent the main chemical pollutants in urban areas. Worldwide, studies that aim to understand the impacts of exposure to these chemicals have gained increasing prominence due to their potential toxicity profile, mainly concerning genotoxicity and carcinogenicity. Human biomonitoring (HB) is an analytical approach to monitoring population exposure to chemicals; however, these studies are still limited in Brazil. Thus, this work aimed to evaluate the exposure of Brazilian pregnant women to PAHs through HB studies. Besides, the risk characterization of this exposure was performed. For this purpose, urine samples from 358 Brazilian pregnant women were used to evaluate 11 hydroxylated metabolites of PAHs employing gas chromatography coupled to mass spectrometry. The 1OH-naphthol and 2OH-naphthol were detected in 100% of the samples and showed high levels, corresponding to 16.99 and 3.62 µg/g of creatinine, respectively. 2OH-fluorene (8.12 µg/g of creatinine) and 9OH-fluorene (1.26 µg/g of creatinine) were detected in 91% and 66% of the samples, respectively. Benzo(a)pyrene (BaP) metabolites were detected in more than 50% of the samples (0.58-1.26 µg/g of creatinine). A hazard index of 1.4 and a carcinogenic risk above 10-4 were found for BaP metabolites in the risk characterization. Therefore, our findings may indicate that exposure to PAHs poses a potential risk to pregnant women's health and a high probability of carcinogenic risk due to their exposure to BaP. Finally, this work shows the need for more in-depth studies to determine the sources of exposure and the implementation of health protection measures regarding the exposure of the Brazilian population to PAHs.

The importance of nutrient ratios in determining elevations in geosmin synthase (geoA) and 2-MIB cyclase (mic) resulting in taste and odour events.

Geosmin synthase (geoA) and 2-MIB cyclase (mic) are key biosynthetic genes responsible for the production of taste and odour (T&O) compounds, geosmin and 2-MIB. These T&O compounds are becoming an increasing global problem for drinking water supplies. It is thought that geosmin and 2-MIB may be linked to, or exacerbated by, a variety of different environmental and nutrient triggers. However, to the best of our knowledge, no studies to date have evaluated the combined effects of seasonality, temperature, and nutrient concentrations on geoA and mic copy numbers in conjunction with T&O concentrations. In this study, environmental triggers behind geosmin and 2-MIB production were investigated in nine reservoirs across Wales, U.K. between July 2019 - August 2020. The abundance of geoA and mic were quantified through quantitative Polymerase Chain Reaction (qPCR). Temporal changes in geoA and geosmin concentrations revealed geoA to be an indicator of monthly geosmin concentrations, although only when geosmin concentrations exceeded 100 ng L-1. Model analysis of a reservoir with elevated geosmin concentrations revealed geoA to be significantly associated with mean temperature (p < 0.001) and the nutrients dissolved reactive silicate (p < 0.001), dissolved iron (p < 0.001), total inorganic nitrogen to phosphorous ratio (TIN:TP) (p < 0.001) and ammonium to nitrate ratio (NH4+:NO3-) (p < 0.001). Sulphate also demonstrated a significant positive linear relationship with geoA (p < 0.001). For mic analysis, NH4+:NO3- was significantly associated with mic (p < 0.05) and an association with dissolved reactive silicate was also observed (p = 0.084). Within this study we also report extreme variance in gene copy numbers between the study seasons. No consistent relationship could be determined for mic copy numbers mL-1 and 2-MIB (ng L-1). The findings from this study indicate that TIN:TP and NH4+:NO3- serve as good predictors for elevated geoA and mic, along with negative linear relationships observed for mean temperature and dissolved reactive silicate. Overall, our findings demonstrate the importance of nutrient concentrations, nutrient ratios and temperature for evidence based predictive capacity of taste and odour events in drinking water reservoirs.

Infrared spectra of North American automobile original finishes. XIV: Identification of Naphthol Red (C.I. Pigment Red 170) in finish layers and in color-coordinated primers.

The naphthol reds are a family of intermediate performance monoazo organic pigments and three of its members, C.I. Pigment Red 148, C.I. Pigment Red 170 (Naphthol Red), and C.I. Pigment Red 188, have been cited as having original automotive paint applications. This study sought to determine which were used in North American vehicle original finishes (1974 to 2019) and how they can be differentiated and identified in situ in paint infrared spectra. Naphthol Red was the only such pigment found and based on a comprehensive survey, absorptions of this pigment were identified in spectra of 12 of the 373 (3%) red or maroon nonmetallic original finishes examined. Identification of Naphthol Red in an unknown finish can thus serve to limit the number of possible source vehicles and spectra of the twelve are presented to facilitate this examination, along with a list of the vehicles that the twelve were used on. For a comparative analysis, identification of this pigment in questioned and known specimens may provide some means of assessing the significance of the finding. Two Inmont red nonmetallic acrylic melamine basecoats, one of which contains Naphthol Red, were found to have quite unusual infrared spectra that are readily distinguished from those of the other 371 finishes examined, and they are discussed. Naphthol Red was also identified in some color-coordinated automotive paint primers and its use appears to be more common in these than in the finish layers.

Urinary concentrations of polycyclic aromatic hydrocarbon and phthalate metabolite mixtures in relation to semen quality among men attending an infertility clinic.

Previous studies have reported that exposure to phthalates and polycyclic aromatic hydrocarbons (PAHs) is individually associated with altered semen quality, but no human studies have evaluated their joint effects of exposure mixtures, a more real-world scenario. We aimed to explore urinary metabolite mixtures of phthalates and PAHs in associations with semen quality. Repeated spot-urine samples gathered from 695 men attending a fertility clinic were analyzed for urinary metabolites of eight phthalates and ten monohydroxylated-PAHs (OH-PAHs). Principal component analysis (PCA)-multivariable linear regression (MLR) model, quantile g-computation (qg-comp), and Bayesian kernel machine regression (BKMR) were applied to estimate the associations of urinary mixtures of phthalate and OH-PAH metabolites with semen quality. The overall effects of urinary mixtures of phthalate and PAH metabolites on semen quality were not statistically significant. However, hydroxynaphthalene (OHNa) factor identified from PCA was monotonically associated with decreased total sperm count and sperm concentration, whereas di(2-ethylhexyl) phthalate (DEHP) factor was non-monotonically related to increased progressive sperm motility and total sperm motility. Qg-comp and BKMR models confirmed these findings and identified 2-OHNa and 2-OHFlu as the primary negative contributors, whereas MEOHP and MEHP as the primary positive contributors. Our findings suggest that exposure to mixtures of naphthalene and DEHP is associated with altered semen quality. The finding is warranted to confirm in further well-designed epidemiological studies.

Kinetic and mechanistic investigation of geosmin and 2-methylisoborneol degradation using UV-assisted photoelectrochemical.

The taste and odor (T&O) problem represented by 2-methylisoborneol (2-MIB) and geosmin (GSM) in water is the multiple undesirable substances in the drinking water and the aquatic industry. In this study, the UV-assisted photoelectrochemical, a prospective advanced oxidation process (AOP), was evaluated for the degradation of 2-MIB and GSM. In contrast to UV photochemical and electrochemical, the degradation ratio of GSM (2-MIB) increase to 96% (95%) in 25 min. The removal ratio and rate depended on reaction time, electrolyte concentration, current density, and water quality parameters (e.g. pH, HCO3-, natural organic matter, and tap water). Among these parameters, a high concentration of electrolyte and acidic solutions could accelerate the rate and increase the ratio, while alkaline conditions and the impurity content had negative effects. Furthermore, the significant role of various reactive species (e.g. HO∙, Cl, ClO, etc) were highlighted by scavenging experiments. Complex free radicals exist was further verified by electron paramagnetic resonance spectroscopy (EPR) experiments. The intermediates were identified and the possible degradation pathways during the UV-assisted photoelectrochemical reactions of both compounds were proposed. Overall, the UV-assisted photoelectrochemical is beneficial to the removal of GSM and 2-MIB in water.

Impact of water quality parameters on geosmin levels and geosmin producers in European recirculating aquaculture systems.

AIMS: Geosmin is associated with off-flavour problems in recirculating aquaculture systems (RAS) and represents an economic problem for the aquaculture industry. This study aims at investigating factors influencing the composition of the bacterial microbiota, in particular the presence of geosmin producers and the environmental and farming factors favouring geosmin accumulation. METHODS AND RESULTS: Several water quality parameters were correlated to the composition of the microbiota with special emphasis on the presence of geosmin producers within 26 different RAS from four European countries. Three novel groups of geosmin-producing bacteria were quantified to identify potential correlations with geosmin concentration. CONCLUSIONS: The microbiome differed significantly between systems. However, phosphate levels, calcium levels and redox potential correlated to geosmin concentration in the water and the presence of the Actinomycetales geosmin-producers but not with the presence of other groups of geosmin-producing bacteria. Oxygen levels and conductivity were found to negatively correlate with geosmin concentration. A large proportion of the detected geosmin producers represented novel taxonomic groups not previously linked with this activity. SIGNIFICANCE AND IMPACT OF THE STUDY: These results improve our understanding of the diversity of microbiota in RAS and the water quality parameters favouring the populations of geosmin-producing bacteria and the production of geosmin.

Occurrences of 2-methylisoborneol and geosmin -degrading bacteria in a eutrophic reservoir and the role of cell-bound versus dissolved fractions.

As taste-and-odor outbreaks are common in surface waters worldwide, extensive studies have focused on the identification of microorganisms involved in the production of 2-methylisoborneol (MIB) and geosmin (GSM). However, fewer studies have tried to identify potential degraders in natural environments. Eagle Creek Reservoir, a temperate and eutrophic water body, experienced two major seasonal odorous outbreaks in 2013 with maximal concentrations of 99.1 (MIB) and 77.3 ng L-1 (GSM). Fractionation analyses of the odorous compounds showed that MIB was found more frequently in the dissolved fraction while GSM was mostly cell-bound. This difference likely impacts taste-and-odor (T&O) compound susceptibility to biodegradation by bacteria. Spearman relationships of epilimnetic samples collected between spring and early fall linked dissolved MIB occurrences to higher abundances of Bacteroidetes like Flavobacterium resistens, F. granuli, F. saliperosum (p < 0.001), F. kamogawaensis (p < 0.01) capable of MIB degradation. Occurrences of cell-bound GSM were correlated to two α-Proteobacteria Novosphingobium hassiacum (p < 0.001) and Sphingomonas oligophenolica (p < 0.01), both identified as potential degraders of GSM. The roles of Pseudomonas and Bacillus were ambiguous, and these genera might have been involved in both compound biodegradations (p < 0.05).

Calibration and measurement of mitochondrial pH in intact adult rat cardiomyocytes.

Mitochondrial pH is a vital parameter of the mitochondrial environment, which determines the rate of many mitochondrial functions, including metabolism, membrane potential, fate, etc. Abnormal mitochondrial pH is always closely related to the health status of cells. Analyzing mitochondrial pH can serve as a proxy for mitochondrial and cellular function. This protocol describes the use of SNARF-1 AM, a pH-sensitive fluorophore, to measure mitochondrial pH. This protocol details the steps to evaluate mitochondrial pH in live adult cardiomyocytes using confocal microscopy. The protocol can be adapted to other adherent cell types. For complete details on the use and execution of this protocol, please refer to Wei-LaPierre et al. (2013).

Compartmentalization of Melanin Biosynthetic Enzymes Contributes to Self-Defense against Intermediate Compound Scytalone in Botrytis cinerea.

In filamentous fungi, 1,8-dihydroxynaphthalene (DHN) melanin is a major component of the extracellular matrix, endowing fungi with environmental tolerance and some pathogenic species with pathogenicity. However, the subcellular location of the melanin biosynthesis pathway components remains obscure. Using the gray mold pathogen Botrytis cinerea, the DHN melanin intermediate scytalone was characterized via phenotypic and chemical analysis of mutants, and the key enzymes participating in melanin synthesis were fused with fluorescent proteins to observe their subcellular localizations. The Δbcscd1 mutant accumulated scytalone in the culture filtrate rather than in mycelium. Excessive scytalone appears to be self-inhibitory to the fungus, leading to repressed sclerotial germination and sporulation in the Δbcscd1 mutant. The BcBRN1/2 enzymes responsible for synthesizing scytalone were localized in endosomes and found to be trafficked to the cell surface, accompanied by the accumulation of BcSCD1 proteins in the cell wall. In contrast, the early-stage melanin synthesis enzymes BcPKS12/13 and BcYGH1 were localized in peroxisomes. Taken together, the results of this study revealed the subcellular distribution of melanin biosynthetic enzymes in B. cinerea, indicating that the encapsulation and externalization of the melanin synthetic enzymes need to be delicately orchestrated to ensure enzymatic efficiency and protect itself from the adverse effect of the toxic intermediate metabolite.IMPORTANCE The devastating gray mold pathogen Botrytis cinerea propagates via melanized conidia and sclerotia. This study reveals that the sclerotial germination of B. cinerea is differentially affected by different enzymes in the melanin synthesis pathway. Using gene knockout mutants and chemical analysis, we found that excessive accumulation of the melanin intermediate scytalone is inhibitory to B. cinerea. Subcellular localization analysis of the melanin synthesis enzymes of B. cinerea suggested two-stage partitioning of the melanogenesis pathway: the intracellular stage involves the steps until the intermediate scytalone was translocated to the cell surface, whereas the extracellular stage comprises all the steps occurring in the wall from scytalone to final melanin formation. These strategies make the fungus avert self-poisoning during melanin production. This study opens avenues for better understanding the mechanisms of secondary metabolite production in filamentous fungi.

Contrasting patterns of 2-methylisoborneol (MIB) vs. geosmin across depth in a drinking water reservoir are mediated by cyanobacteria and actinobacteria.

Taste and odor episodes caused by off-flavor secondary metabolites, such as 2-methylisoborneol (MIB) and geosmin, pose one of the greatest challenges for drinking water utilities around the world. The prevalence of these compounds is predicted to increase in the future as a function of nutrient enrichment and elevated temperatures of surface drinking water sources. We conducted a manipulative field experiment in a drinking water reservoir to elucidate patterns for two taste and odor compounds, MIB and geosmin, as well as two taxa known to produce these compounds, phytoplankton (more specifically, cyanobacteria) and actinobacteria, across different depths in response to nutrient enrichment with two common dissolved nitrogen forms, organic urea or inorganic nitrate. In general, we found that MIB levels increased by greater than 250% with nutrient enrichment mediated by increased phytoplankton biomass. However, the effect of the fertilization treatments on MIB decreased with depth with a 35% reduction at 7 m versus 1.5 m. In contrast, geosmin levels reached a maximum at the lowest measured depth (7 m), were unaffected by the fertilization treatments, and followed a similar pattern to the abundance of actinobacteria. Thus, our data suggest that the positive response of phytoplankton (e.g., cyanobacteria, such as Oscillatoria species) to the fertilization treatments is likely responsible for increased MIB, while geosmin concentrations may be a function of actinobacteria-mediated decomposition in the hypolimnion in our study system.

Melanin and chromoblastomycosis agents: Characterization, functions, and relation with antifungals.

Melanins are a diverse group of dark pigments with similar properties. In fungi, the most studied is the dihydroxynaphtalene (DHN)-melanin, present in several species including all the chromoblastomycosis agents, a chronic, disabling, and recalcitrant subcutaneous mycosis. It is synthesized in a pathway known as the pentaketide pathway, which has the agrochemical tricyclazole as an inhibitor, widely used in in vitro studies because it does not prevent the growth of fungi. There are different methodologies for qualitative and quantitative analyses of DHN-melanin, which made it possible to discover its important structural and antioxidant functions, with melanin acting as a protective factor against the host's immune system. Also, it can interact with some of the main antifungals of medical interest, reducing its activity and the susceptibility of fungi to these agents. This review aims to discuss the aspects of DHN-melanin, focusing on chromoblastomycosis, bringing the main findings of the published scientific studies, and highlighting the need for further research to understand this important fungal pathogenicity and a virulence factor.

Comparative assessment of the degradation of 2-methylisoborneol and geosmin in freshwater using advanced oxidation processes.

Traditional methodologies of conventional drinking water treatment are unable to remove some chemical compounds, such as those that cause odor and taste in drinking water. The present work aims to evaluate the efficiency of advanced oxidations processes, using UV radiation, O3 and O3 + UV in the degradation of geosmin (GSM) and 2-methylisoborneol (2-MIB) in synthetic samples. The efficiency of the processes was monitored by Gas Chromatography coupled with Mass Spectrometry using solid phase microextration technique. Experiments were carried out for 45 min with samplings every 15 min. The degradation results showed that UV radiation alone was not efficient for the degradation of both compounds. The fasted decay was observed by the combined use of O3 and UV with an ozone concentration of 15.84 mg L-1. Under these conditions, the final concentration of GSM was below the limit of quantification, so that approximately 99% of the initial concentration was degraded, while 2-MIB was degraded by 95%. With the same O3 concentration without the use of UV radiation, 63% and 65.7% of MIB and GSM, respectively, were removed. Higher efficiency of the treatment was observed with a higher O3 concentration which allows a shorter reaction time.

Preparation of sulfur-doped carbon quantum dots from lignin as a sensor to detect Sudan I in an acidic environment.

To achieve a rapid and facile quantitative evaluation of Sudan I illegally added in ketchup, fluorescent carbon quantum dots with excellent stability in acidic environments are required as the actual pH value of ketchup is close to 4.0. In this paper, we developed a green approach to prepare sulfur-doped carbon quantum dots (SCQDs) via hydrothermal treatment of lignin, isolated from pre-hydrolysis liquor, in sulfuric acid solution. The resultant SCQDs from lignin possessed sulfur-containing groups, which exhibited excellent fluorescence with a quantum yield up to 13.5% and good stability in acidic environments with a wide pH range of 0-5.0. Therefore, the SCQDs were successfully employed as a sensor to detect Sudan I in acidic solutions with excellent selectivity and sensitivity. The linear range for Sudan I was 0-40 µM, while the limit of detection was 0.12 µM. In addition, the fluorescent indicator paper functionalized with SCQDs also showed outstanding selectivity to Sudan I. The proposed SCQD sensing system not only displayed application potential for quantitative evaluation of Sudan I dye in practical samples, but also provided a way to convert lignin-based waste into highly valued nanoscale materials.

Luminescent Chemosensor Based on Ru(II) Bipyridine Complex for Detection of Sudan I through Inner Filter Effect.

Presence of Sudan I in food stuff can be problematic and need to be checked in order to protect our health from possible carcinogen. Therefore, it is essential to detect Sudan I by efficient, rapid and reliable method. In this work, we have designed a Ru(II) polypyridyl complex, [Ru(bpy)2(CIP)]2+ probe for the selective and sensitive detection of Sudan I. Upon addition of Sudan I to the solution of [Ru(bpy)2(CIP)]2+ in ethanol, the luminescence quenched rapidly, and linear concentration range with analyte has been obtained from 0.8 to 100 µM with the limit of detection as low as 0.26 µM (S/N = 3). The effective luminescence quenching was resulted due to the inner filter effect (IFE) between luminophore, [Ru(bpy)2(CIP)]2+ and quencher, Sudan I. Our spectroscopic study was essentially provided sufficient analytical evidences in order to prove occurrence of IFE mechanism. As there were no interferences observed in luminescence measurement from the other substances the present probe has been successfully applied for the detection of Sudan I in commercial chili powder sample, making the probe suitable for practical usage.

Development of a micellar electrokinetic capillary chromatography method for the determination of four naphthalenediols in cosmetics and a comparison with a HPLC method.

A micellar electrokinetic capillary chromatography (MEKC) method with ultraviolet visible (UV) detection was used for the determination of 1,7-naphthalenediol, 2,3-naphthalenediol, 1,5-naphthalenediol, and 2,7-naphthalenediol in cosmetics. The current method for their determination in various cosmetics is high-performance liquid chromatography (HPLC). Separation conditions affecting the MEKC method were optimized as 20 mM Na2 B4 O7 -50mM SDS, pH 9.8, with 22 kV applied voltage and UV detection at 230 nm. Under optimal conditions, electrophoretic analysis was completed in less than 6 min, with limit of detection (LOD) of 0.070-0.19 µg/mL and limit of quantitation (LOQ) of 0.23-0.63 µg/mL. A good linear relationship (r2 > 0.99) was obtained at the range of 0.75-20 µg/mL. Recoveries for the four naphthalenediols in lotion, loose powder, and sun cream are between 91.2-107.2% with relative standard deviation (RSD) less than 4.04%. The method has been successfully applied to the determination of the four naphthalenediols in different kinds of cosmetics. A comparison with HPLC-UV method was also carried out according to the National Standards of the People's Republic of China. The results obtained by MEKC and HPLC methods are comparable, but the proposed MEKC method can help us obtain a much shorter detection time and low cost.

Qualitative and quantitative analysis based on digital images to determine the adulteration of ketchup samples with Sudan I dye.

Sudan I is a synthetic-azo dye commonly used to adulterate foods to increase sensory appearance. However, it is banned due to its carcinogenic, mutagenic and genotoxic properties, which represent a serious risk to human health. Thus, this paper proposes a feasibility study to identify and quantify Sudan I dye in ketchup samples using colour histograms (obtained from digital images) and multivariate analysis. The successive projections algorithm coupled with linear discriminant analysis (SPA-LDA) classified correctly all samples, while the partial least squares coupled with SPA for interval selection (iSPA-PLS) quantified adequately the adulterant, attaining values of RMSEP of 11.64 mg kg-1, R2 of 0.96, RPD of 5.28, REP of 13.63% and LOD of 39.45 mg kg-1. Therefore, the proposed methodology provides a simple, fast, inexpensive, promising analytical tool for the screening of both the quality and safety of ketchup samples. As a consequence, it can help to protect the consumer's health.

A novel cyanobacterial geosmin producer, revising GeoA distribution and dispersion patterns in Bacteria.

Cyanobacteria are ubiquitous organisms with a relevant contribution to primary production in all range of habitats. Cyanobacteria are well known for their part in worldwide occurrence of aquatic blooms while producing a myriad of natural compounds, some with toxic potential, but others of high economical impact, as geosmin. We performed an environmental survey of cyanobacterial soil colonies to identify interesting metabolic pathways and adaptation strategies used by these microorganisms and isolated, sequenced and assembled the genome of a cyanobacterium that displayed a distinctive earthy/musty smell, typical of geosmin, confirmed by GC-MS analysis of the culture's volatile extract. Morphological studies pointed to a new Oscillatoriales soil ecotype confirmed by phylogenetic analysis, which we named Microcoleus asticus sp. nov. Our studies of geosmin gene presence in Bacteria, revealed a scattered distribution among Cyanobacteria, Actinobacteria, Delta and Gammaproteobacteria, covering different niches. Careful analysis of the bacterial geosmin gene and gene tree suggests an ancient bacterial origin of the gene, that was probably successively lost in different time frames. The high sequence similarities in the cyanobacterial geosmin gene amidst freshwater and soil strains, reinforce the idea of an evolutionary history of geosmin, that is intimately connected to niche adaptation.

Microdroplet-captured tapes for rapid sampling and SERS detection of food contaminants.

Simple, effective, and rapid detection of chemically relevant hazards is a highly desirable research goal, which can provide early-warning information to improve the patient-care outcomes for public health. Here, we introduce a microdroplet-captured tape toward rapid SERS screening of food contaminants. The dominant sensing unit lies on functionalized microwell in conductive carbon tapes, which is simply prepared by physical punching, magnetron sputtering and electrochemical deposition of Au nanodendrites. The tape-based sensors not only possess highly branched Au nanodendrites in microwell for promoting SERS activity, but also enable anchoring the microdroplets via direct dip-pulling from pristine analytes solutions upon sticky incorporated on a glove. Early-warning SERS detection of food contaminants including Sudan-1, thiram, and thiabendazole from the real samples can be achieved by such simple sampling method. These tape-based sensors with a facile operation module and accessible signal read-out represent an innovative point-of-care testing (POCT) device for forensic, military, consumer protection, environmental monitoring, and food safety applications.