Fundamental and applied aspects of catechins from different sources: a review

Catechins belong to the group of flavonoids. Numerous studies show that consuming foods rich in catechins such as vegetables, fruits and especially teas may decrease the risk of developing various diseases. Therefore, we present in this compilation a critical and detailed analysis of the works published in the last 6 years and a guide for the reader with the main analytical techniques of quantification, in vitro and in vivo biological activities, the mechanisms of action in the organism and the bioaccessibility in treating the gastrointestinal effects of catechins from different matrices. The information presented in this review is important for a broad understanding of benefits that catechins can bring to human health and can be taken as an example for the study of new matrices, new effects and possible forms of application, such as dietary supplements or functional food ingredients for health promotion and the reduced risk for developing diseases.     

Attributing human foodborne illness to food sources and water in Latin America and the Caribbean using data from outbreak investigations

Foodborne pathogens are responsible for an increasing burden of disease worldwide. Knowledge on the contribution of different food sources and water for disease is essential to prioritize food safety interventions and implement appropriate control measures. Source attribution using outbreak data utilizes readily available data from outbreak surveillance to estimate the contribution of different sources to human disease. We developed a probabilistic model based on outbreak data that attributes human foodborne disease by various bacterial pathogens to sources in Latin America and the Caribbean (LA&C). Foods implicated in outbreaks were classified by their ingredients as simple foods (i.e. belonging to one single food category), or complex foods (i.e. belonging to multiple food categories). For each agent, the data from simple-food outbreaks were summarized, and the proportion of outbreaks caused by each category was used to define the probability that an outbreak was caused by a source. For the calculation of the number of outbreaks attributed to each source, simple-food outbreaks were attributed to the single food category in question, and complex-food outbreaks were partitioned to each category proportionally to the estimated probability. We analysed all bacterial pathogens together, focused on important bacterial pathogens separately, and, when data were sufficient, performed analyses by country, decade and location. Between 1993 and 2010, 6313 bacterial outbreaks were reported by 20 countries. In general, the most important sources of bacterial disease were meat, dairy products, water and vegetables in the 1990s, and eggs, vegetables, and grains and beans in the 2000s. We observed fluctuations of the most important sources of disease for each pathogen between decades and countries, which may be a consequence of changes in the control of zoonotic disease over the years, of changes in food consumption habits, or of changes in public health focus and availability of data of different pathogens. This study identified data gaps in the region and highlighted the importance of effective surveillance systems to identify sources of disease. Still, the application of this method for source attribution in the LA&C region was successful, and we concluded that this approach can be used to attribute disease to food sources and water in other regions, including developing regions with limited data on the public health impact of foodborne diseases.     

Flavanols from green tea and phenolic acids from coffee: critical quantitative evaluation of the pharmacokinetic data in humans after consumption of single doses of beverages

Coffee contains a complex mixture of chlorogenic acids, which are mainly ferulic and caffeic acids ester-linked to quinic acid. Green tea contains flavanols, mainly (-)-epigallocatechin gallate (EGCG), (-)-epigallocatechin (EGC) and (-)-epicatechin (EC). For healthy humans, we identified seven studies on green tea in liquid form and five on coffee beverage reporting single-dose plasma pharmacokinetics. Weighted averages, based on the number of subjects, and elimination of outliers, allowed estimation of some pharmacokinetic parameters. After consumption of an "average" cup of green tea containing 112 mg of (-)-epigallocatechin gallate, 51 mg of EGC and 15 mg of EC in 200 mL, the predicted C(max) values (total free and sulfate/glucuronide conjugates) in plasma are 125, 181 and 76 nM, respectively, together with 94 nM methyl-EGC and 51 nM methyl-EC (standard deviation <20%). After consumption of an "average" cup of coffee (160 mg total chlorogenic acids (0.46 mmol)/200 mL), predicted C(max) values of caffeic, ferulic, isoferulic, dihydrocaffeic and dihydroferulic acids are 114, 96, 50, 384 and 594 nM, respectively (too few studies to calculate standard deviation). Most studies report a very low amount of intact chlorogenic acids in plasma, with one exception. More studies on absorption of chlorogenic acids from coffee are required, including dose-response studies.     

Pyrogenic inputs of anthropogenic Pb and Hg to sediments of the Hood Canal, Washington, in the 20th century: source evidence from stable Pb isotopes and PAH signatures

Combustion-derived PAHs and stable Pb isotopic signatures ((206)Pb/(207)Pb) in sedimentary records assisted in reconstructing the sources of atmospheric inputs of anthropogenic Pb and Hg to the Hood Canal, Washington. The sediment-focusing corrected peak fluxes of total Pb and Hg (1960-70s) demonstrate that the watershed of Hood Canal has received greater atmospheric inputs of these metals than its mostly rural land use would predict. The tight relationships between the Pb, Hg, and organic markers in the cores indicate that these metals are derived from industrial combustion emissions. Multiple lines of evidence point to the Asarco smelter, located in the Main Basin of Puget Sound, as the major emission source of these metals to the watershed of the Hood Canal. The evidence includes (1) similar PAH isomer ratios in sediment cores from the two basins, (2) the correlations between Pb, Hg, and Cu in sediments and previously studied environmental samples including particulate matter emitted from the Asarco smelter's main stack at the peak of production, and (3) Pb isotope ratios. The natural rate of recovery in Hood Canal since the 1970s, back to preindustrial metal concentrations, was linear and contrasts with recovery rates reported for the Main Basin which slowed post late 1980s.     

Critical evaluation of the extrapolation of data relative to antioxidant function from the laboratory and their implications on food production and human health: a review

The use of the word ‘antioxidant’ has become widespread in food science, nutrition and consumer language, having become associated with potential health benefits linked to consuming sources of antioxidants in our food supply. However, there is significant doubt about direct antioxidant effects on human health. This may partly relate to methodology used for assessing functionality and activity (both in food matrices and in human health) as well as how data is extrapolated with respect to health based on laboratory analyses. In this review, the purpose and impact of antioxidants in food systems and on human health will be discussed, along with highlighting the best current methodology for analysing antioxidant effects. Consideration will also be made with respect to recommendations of how antioxidant activity should be reported, with a focus on being both scientifically accurate as well as minimising the risk of unwarranted extrapolations of benefits which might mislead end consumers.     

Carbon isotopic composition of fatty acids in the marine aerosols from the western North Pacific: implication for the source and atmospheric transport

A combined molecular and isotopic approach was used in this study to reveal the source and transport of aerosols at a remote oceanic site. Fatty acid distributions and stable carbon isotopic compositions of individual fatty acids were determined in the aerosol samples collected at Chichi-Jima in the western North Pacific over a period of 41 months. Fatty acid concentration and isotopic composition delta13C (vs PDB) exhibited temporal variations. Concentrations of fatty acids (C12-C34) ranged from 7.6 to 20.7 ng/m3. The concentrations of lower molecular weight (LMW) fatty acids (C12 -C19) tend to decrease in winter and increase in summer, whereas the higher molecular weight (HMW) C20-34 fatty acids exhibited a reversed trend. Compound-specific isotopic analysis revealed that the LMW fatty acids exhibited consistently less negative delta13C values than the HMW fatty acids. However, both the LMW and HMW fatty acids displayed a similar trend of temporal variations in delta13C, suggesting thatthe fatty acids experienced similar atmospheric pathways and transport processes to the remote marine atmosphere, whereas the difference in absolute delta13C reflects the different sources of the fatty acids.     

Human exposure assessment: a case study of 8 PAH contaminated soils using in vitro digestors and the juvenile swine model

In vitro digestors can be used to provide bioaccessibility values to help assess the risk from incidental human ingestion of contaminated soils. It has been suggested that these digestors may need to include a lipid sink to mimic human uptake processes. We compare the correspondence between in vivo polycyclic aromatic hydrocarbon (PAH) uptake for eight different PAH contaminated soils with PAH release in in vitro digestors in the presence and absence of a lipid sink. Lipid sinks were essential to the success of the in vitro digestors in predicting juvenile swine PAH uptake. In the presence of the lipid sink, results of the In Vitro Digestion model (IVD) closely corresponded with a slope of 0.85 (r(2) = 0.45, P < 0.07) to the in vivo results. The Relative Bioaccessibility Leaching Procedure (RBALP) results did not correspond to the in vivo study but did tightly reflect total soil PAH concentration. We conclude that the basis of this difference between digestors is that the RBALP used an aggressive extraction technique that maximized PAH release from soil. Systemic uptake in juvenile swine was not linked to soil PAH concentration but rather to the thermodynamic properties of the soil.     

Tracking the sources of nitrate in groundwater using coupled nitrogen and boron isotopes: a synthesis

Nitrate (NO3) is one of the world's major pollutants of drinking water resources. Although recent European Directives have reduced input from intensive agriculture, NO3 levels in groundwater are approaching the drinking water limit of 50 mg L(-1) almost everywhere. Determining the sources of groundwater contamination is an important first step toward improving its quality by emission control. It is with this aim that we review here the benefit of using a coupled isotopic approach (delta15N and delta11B), in addition to conventional hydrogeological analyses, to trace the origin of NO3 in water. The studied watersheds include both fractured bedrock and alluvial (subsurface and deep) hydrogeological contexts. The joint use of nitrogen and boron isotope systematics in each context deciphers the origin of NO3 in the groundwater and allows a semi-quantification of the contributions of the respective pollution sources (mineral fertilizers, wastewater, and animal manure).     

Dietary interventions to contrast the onset and progression of diabetic nephropathy: A critical survey of new data

This article is a critical overview of recent contributions on the dietary corrections and the foods that have been claimed to delay or hinder the onset of diabetic nephropathy (DN) and its progression to end-stage renal disease. Innovative dietary and behavioral approaches to the prevention and therapy of DN appear to be the most captivating in consideration of the rather well-established protocols for glucose and blood pressure control in use. In addition to restricted caloric intake to contrast obesity and the metabolic syndrome, adjustments in the patient's macronutrients intake, and in particular some degree of reduction in protein, have been long considered in the prevention of DN progression. More recently, the focus has shifted to the source of proteins and the content of glycotoxins in the diet as well as to the role of specific micronutrients. Few clinical trials have specifically addressed the role of those micronutrients associated with diet proteins that show the most protective effect against DN. Research on clinical outcome and mechanisms of action of such micronutrients appears the most promising in order to develop both effective intervention on nutritional education of the patient and selection of functional foods capable of contrasting the onset and progression of DN.     

Aircraft measurements of nitrogen and phosphorus in and around the Lake Tahoe Basin: implications for possible sources of atmospheric pollutants to Lake Tahoe

Atmospheric deposition of nitrogen (N) and phosphorus (P) into Lake Tahoe appears to have been a major factor responsible for the shifting of the lake's nutrient response from N-limited to P-limited. To characterize atmospheric N and P in and around the Lake Tahoe Basin during summer, samples were collected using an instrumented aircraft flown over three locations: the Sierra Nevada foothills east of Sacramento ("low-Sierra"), further east and higher in the Sierra ("mid-Sierra"), and in the Tahoe Basin. Measurements were also made within the smoke plume downwind of an intense forest fire just outside the Tahoe Basin. Samples were collected using a denuder-filter pack sampling system (DFP) and analyzed for gaseous and water-soluble particle components including HNO3/ NO3-, NH3 /NH4+, organic N (ON), total N, SRP (soluble reactive phosphate) and total P. The average total gaseous and particulate N concentrations (+/- 1sigma) measured over the low- and mid-Sierra were 660 (+/- 270) and 630 (+/- 350) nmol N/m3-air, respectively. Total airborne N concentrations in the Tahoe samples were one-half to one-fifth of these values. The forest fire plume had the highest concentration of atmospheric N (860 nmol N/m3-air) and a greater contribution of organic N (ON) to the total N compared to nonsmoky conditions. Airborne P was rarely observed over the low- and mid-Sierra but was present at low concentrations over Lake Tahoe, with average +/- 1sigma) concentrations of 2.3 +/- 2.9 and 2.8 +/- 0.8 nmol P/m3-air under typical clear air and slightly smoky air conditions, respectively. Phosphorus in the forestfire plume was present at concentrations approximately 10 times greater than over the Tahoe Basin. P in these samples included both fine and coarse particulate phosphate as well as unidentified, possibly organic, gaseous P species. Overall, our results suggest that out-of-basin emissions could be significant sources of nitrogen to Lake Tahoe during the summer and that forest fires could be important sources of both N and P.     

Monitoring of the prokaryotic diversity in pit mud from a Luzhou‐flavour liquor distillery and evaluation of two predominant archaea using qPCR assays

Pit mud plays a crucial role in the production of the Luzhou‐flavour liquor. Its quality directly determines liquor quality and yield. The aged pit mud produced good quality liquor but aging pit mud did not. The aim of this work was to investigate the prokaryotic diversity of the aged and aging pit mud from a Luzhou‐flavour liquor distillery using molecular methods. Two bacteria‐specific and two archaea‐specific 16S rRNA gene clone libraries were constructed and analysed using amplified ribosomal DNA restriction analysis. A total of 273 clones were studied, which resulted in 28 operational taxonomic units. Bacteroidetes and Firmicutes predominated in both the aged and aging pit mud, but Synergistetes and Actinobacteria were only detected in the aged pit mud. The family Methanosaeta dominated in the aged pit mud, while the Methanosarcina predominated in the aging pit mud. These results were confirmed using two genus‐specific quantitative real time PCR assays. This research distinguished microbial community structure in the aged and aging pit mud for the first time, and has laid an initial foundation for identifying good quality pit mud and for maintaining the quality of pit mud. Copyright © 2014 The Institute of Brewing & Distilling     

Food biotechnologies and retail ethics: a survey of UK retailers' views on the use of two dairy technologies

Consumer attitudes to biotechnologies will significantly influence their use in the food industry. However, retailers also have a powerful position in the food system and play an influential role in defining and framing the use of biotechnology. This raises a number of ethical issues. This case study of the role of retailer behaviour in technology use and acceptability examined the implications of retailers' attitudes for the use of two dairy technologies, bovine somatotrophin (bST) and automatic milking systems (AMS), and for any effects these attitudes might have upon other interest groups. Responding retailers viewed bST as ethically unacceptable, whereas AMS use was characterised as acceptable to most. Retailers appeared to apply a precautionary approach to these two biotechnologies. Although the nature of retailer social responsibility is ill-defined, their powerbroker position would seem to highlight a need to explore these ethical issues further.     

Determination of critical aggregation concentration and aggregation number of acid-soluble collagen from walleye pollock (Theragra chalcogramma) skin using the fluorescence probe pyrene

The aim of this paper was to investigate the critical aggregation concentration and aggregation number of acid-soluble collagen from walleye pollock (Theragra chalcogramma) skin using the fluorescence probe pyrene. Results showed that pyrene was fit for studying the aggregation behaviour of collagen in sodium phosphate buffer at pH 7.2. The plots of the pyrene I₁/I₃ ratio, as a function of the logarithm of total collagen concentration, revealed a typical sigmoidal decrease, the critical aggregation concentration (CAC) from which was determined to be at 0.48 mg/ml. The subsequent transient fluorescence decay study indicated that the aggregation number of collagen was not constant, but varied with different concentrations of collagen. The structure of the aggregates tended to be stable, when the collagen concentration exceeded 1.2 mg/ml.     

Pasteurization of milk and the heat resistance of Mycobacterium avium subsp. paratuberculosis: a critical review of the data

Mycobacterium avium subsp. paratuberculosis (M. paratuberculosis) causes Johne's disease in ruminants (including cattle, sheep and goats) and other animals, and may contribute to Crohn's disease in humans. This possibility, and the fact that M. paratuberculosis may be present in raw milk, make it important to ensure that the heat treatment specified for pasteurization of milk will give acceptable inactivation of this bacterium, with an adequate margin of safety. Published studies of the heat resistance of this bacterium in milk have given widely differing results. Possible reasons for these differences, and the technical problems involved in the work, are reviewed. It is concluded that there is a need (i) for the adoption of an agreed Performance Criterion for pasteurization of milk in relation to this bacterium, (ii) a need for definitive laboratory experiments to understand and determine the heat resistance of M. paratuberculosis, and (iii) a need for an assessment of whether the minimum heat treatments specified at present for pasteurization of milk (Process Criteria) will meet the Performance Criterion for M. paratuberculosis. Measures are also required to ensure that commercial processes deliver continually the specified heat treatment, and to ensure that post-pasteurization contamination is avoided.     

Risks and pitfalls of sensory data analysis for shelf life prediction: Data simulation applied to the case of coffee

Shelf life determination by means of sensory analysis is thought to be of paramount importance even in case of a microbiologically stable food. Several approaches are found in literature, both in terms of data collection and data processing. Whatever method is used, the subjectivity in the choice of some parameters for data collection and analysis can deeply influence the final result. We put in evidence some typical pitfalls that the researcher should avoid when planning the test and analysing data. A comparison between the most utilized techniques in sensory data processing for shelf life prediction is reported, taking as a fil rouge the case of coffee. In particular, a non-linear regression, a logistic regression and a survival models were applied to simulated data frames of coffee. We evaluated the influence of the choice of acceptability limits, as well as the effect of data variability and we found out that they strongly influence predictions, as well as the panel and the batch of product do. We suggest that in case of microbiologically stable food, like coffee, shelf life is not univocal and it is a choice of the company or the researcher, rather than the result of the interaction between product and consumer.     

A comparative study on different concentration methods of extracts obtained from two raspberries (Rubus idaeus L.) cultivars: evaluation of anthocyanins and phenolics contents and antioxidant activity

The effects of conventional (CV) and microwave (MW) heating on total soluble solid (TSS) content, total anthocyanin content (TAC), total phenolic content (TPC) and antioxidant activity of raspberry juice obtained from two cultivars of Amol (AM) and Siyahkal (SK) were scrutinised. Antioxidant activity of the juices was measured by 2,2 diphenyl‐1‐picrylhydrazyl (DPPH) radical scavenging capacity and expressed as EC₅₀ value. In the both methods, the concentration rate constant for the juices was significantly decreased by increasing operational pressure from 12 to 100 kPa (P < 0.05). A first‐order reaction kinetic model was successfully fitted for the degradation of monomeric anthocyanins at all operating pressures. The results also showed that thermal treatment of MW compared CV in both SK and AM cultivars caused a lower decrease in the TAC, TPC and antioxidant activity. Moreover, the changes in trend of the antioxidant activities due to the thermal treatment were positively correlated with the TPC (r = 0.74, P < 0.05) and TAC (r = 0.61, P < 0.05).     

Use of fecal steroids to infer the sources of fecal indicator bacteria in the Lower Santa Ana River Watershed, California: sewage is unlikely a significant source

The Santa Ana River (SAR), CA and adjacent wetlands have been identified as potential sources of fecal indicator bacteria (FIB) to the surf zone at Huntington Beach, CA. A suite of fecal steroids, including coprostanol (COP), epicoprostanol (eCOP), cholesterol (CHOE), cholestanol (CHOA), alpha-cholestanone (aONE), beta-cholestanone (bONE), beta-sitosterol (bSIT), stigmasterol (STIG), stigmastanol (STAN), and campesterol (CAM), were used as chemical markers to examine whether sewage was a significant source of FIB within the lower Santa Ana River watershed. A total of 54 water samples were collected from three locations in the intertidal zone near the mouth of the Santa Ana River at different tidal stages. Steroid ratios in SAR samples were different from those found in raw and treated sewage from a local wastewater treatment plant or in nearby effluent plume and did not appear to be influenced by the sampling location, daily tides, and spring/neap tidal cycle. The characteristics of steroid ratios suggested a diagenetic ratherthan a biogenic source forthe COP content of the samples. The log-based concentrations of COP and FIB in the SAR samples were not significantly correlated, inconsistent with sewage being the source of FIB in the study area. In addition, multivariate statistical analysis showed that the concentrations of FIB were better correlated with bird fecal steroids than with the typical sewage sterols. The results implied that sewage was not a significant source of fecal steroids, and therefore perhaps FIB to the study area. Instead, birds may be one possible source of the intermittently high levels of FIB observed in the lower Santa Ana River watershed and the nearby surf zone.