Validation by a Collaborative Interlaboratory Study of an ELISA Method for the Detection of Caseinate Used as a Fining Agent in Wine

The clarification or fining of wine removes undesirable substances such as proteins, phenols, and tannin compounds that would cloud the wine and cause bitterness and astringency. Caseinates have useful fining properties, but their residues could present a risk for allergic subjects. A commercial kit that was developed to detect caseinates in food has been examined for its applicability to a wine matrix; it is sensitive to caseinates at concentrations as low as 1 ppm. The general characteristics of the caseinate assay, described below in detail, are as follows. It is a sandwich enzyme-linked immunosorbent assay (ELISA): the microplate is first coated with a specific anti-casein antibody; and after incubation with the wine sample, a secondary anti-casein antibody conjugated with horseradish peroxidase is added to form a sandwich. The antibodies have been tested for their immunoreactivity and the reproducibility of antigen recognition has been measured. An interlaboratory collaborative trial was organized to evaluate the performance of this ELISA method and its ease of use by laboratories routinely dealing with wine/food analyses. The results satisfy the criteria established by the International Organisation of Vine and Wine in the Compendium of International Methods of Analysis MA-EAS1-07-ETCOL.     

Formation and Degradation of Beta-casomorphins in Dairy Processing

Milk proteins including casein are sources of peptides with bioactivity. One of these peptides is beta-casomorphin (BCM) which belongs to a group of opioid peptides formed from β-casein variants. Beta-casomorphin 7 (BCM7) has been demonstrated to be enzymatically released from the A1 or B β-casein variant. Epidemiological evidence suggests the peptide BCM 7 is a risk factor for development of human diseases, including increased risk of type 1 diabetes and cardiovascular diseases but this has not been thoroughly substantiated by research studies. High performance liquid chromatography coupled to UV-Vis and mass spectrometry detection as well as enzyme–linked immunosorbent assay (ELISA) has been used to analyze BCMs in dairy products. BCMs have been detected in raw cow's milk and human milk and a variety of commercial cheeses, but their presence has yet to be confirmed in commercial yoghurts. The finding that BCMs are present in cheese suggests they could also form in yoghurt, but be degraded during yoghurt processing. Whether BCMs do form in yoghurt and the amount of BCM forming or degrading at different processing steps needs further investigation and possibly will depend on the heat treatment and fermentation process used, but it remains an intriguing unknown.     

Spoilage microbiota associated to the storage of raw meat in different conditions

The spoilage of raw meat is mainly due to undesired microbial development in meat during storage. The type of bacteria and their loads depend on the initial meat contamination and on the specific storage conditions that can influence the development of different spoilage-related microbial populations thus affecting the type and rate of the spoilage process. This review focuses on the composition of raw meat spoilage microbiota and the influence of storage conditions such as temperature, packaging atmosphere and use of different preservatives on the bacterial diversity developing in raw meat. In addition, the most recent tools used for the detection and identification of meat microbiota are also reviewed.     

High performance size-exclusion chromatography analysis of polar compounds applied to refined, mild deodorized, extra virgin olive oils and their blends: An approach to their differentiation

An investigation was carried out to evaluate the use of High Performance Size-Exclusion Chromatography (HPSEC) of polar compounds of refined, mild deodorized, extra virgin olive oils as well as of their blends, in attempting to reveal significant differences in the amounts of the substance classes constituting polar compounds among these oils. Two sets of blends were prepared by mixing an extra virgin olive oil with both refined and mild deodorized olive oils in increasing amounts. The obtained data highlighted that the triacylglycerol oligopolymers were absent or present in traces in the extra virgin olive oil, while their mean amount was equal to 0.04 g/100 g and 0.72 g/100 g in mild deodorized and refined olive oils, respectively. Oxidized triacylglycerols and diacylglycerols were more abundant in mild deodorized oil and refined oil than in extra virgin olive oil. The Factorial Discriminant Analysis of the data showed that the HPSEC analysis could reveal the presence of refined/mild deodorized oils in extra virgin olive oils. In particular, the classification functions obtained allowed designation of mixtures containing at least 30 g/100 g of mild deodorized oil and all those containing refined olive oil as deodorized oil, therefore as oils subjected to at least a mild refining treatment.     

Peptides from water buffalo cheese whey induced senescence cell death via ceramide secretion in human colon adenocarcinoma cell line

Scope: Milk proteins are a source of bioactive peptides. Recent studies have indicated that protein‐derived peptides released in buffalo cheese acid whey exert a cytomodulatory effect in human epithelial colon cancer (CaCo2) cells. The aim of the present study was to explain the molecular mechanism involved in the response of CaCo2 cells to oxidative stress in the presence of peptide fractions of buffalo cheese whey, purified and characterized by mass spectrometry. Methods and results: We demonstrated that treatment of CaCo2 treated with H₂O₂ (H‐CaCo2) cells with a partially purified peptide sub‐fraction (f3) from buffalo cheese acid whey induced a reduction of mitochondrial superoxide anion with subsequent decrease in heat shock protein 70 and 90 expression. Moreover, we observed a 5‐fold decrease in cyclin A expression and cell cycle arrest in G1/G0 phases. These responses were associated with increased activity of alkaline phosphatase and beta‐galactosidase, markers of differentiation and senescence respectively. Conclusions: The structural characterization of the active peptide fraction and the elucidation of the effects induced by its treatment on H‐CaCo2 cells in vitro demonstrated an activity of this peptide sub‐fraction in the modulation of cell cycle, thus suggesting potential application for the development of nutraceuticals as well as health‐promoting functional foods.     

Absence of allergenic residues in experimental and commercial wines fined with caseinates

The possible presence of allergenic residues in wines treated with one of the potassium caseinates used as fining agents has been investigated.     

Complexity‐reduced in the hydroclimatological modelling of aquifer's discharge

Climate variability induces considerable interannual fluctuations in spring discharge, especially in mountain areas, where groundwater is recharged mainly by rain and snow melt. This study presents the discharge climatological model (DISCLIM), which was developed to test a complexity‐reduced approach to perform historical reconstruction in the lack of physical assumptions. The Mount Cervialto aquifer (Southern Italy) is the test site, where a powerful karst spring is monitored since the 1920s and is very sensitive to climatic conditions. DISCLIM incorporates seasonal precipitation and climate indicators only. Despite its simplicity, DISCLIM has been able to well estimate the yearly fluctuations of discharge hydrological, explaining about 90% of the interannual variability at the calibration stage, and more than 80% at validation stage. This means that DISCLIM can be easily used for estimating the discharge in historical times, when no all the hydrological balance data are available for the purpose.     

The Roles of Coenzyme Q in Disease: Direct and Indirect Involvement in Cellular Functions

Coenzyme Q (CoQ) is a key component of the respiratory chain of all eukaryotic cells. Its function is closely related to mitochondrial respiration, where it acts as an electron transporter. However, the cellular functions of coenzyme Q are multiple: it is present in all cell membranes, limiting the toxic effect of free radicals, it is a component of LDL, it is involved in the aging process, and its deficiency is linked to several diseases. Recently, it has been proposed that coenzyme Q contributes to suppressing ferroptosis, a type of iron-dependent programmed cell death characterized by lipid peroxidation. In this review, we report the latest hypotheses and theories analyzing the multiple functions of coenzyme Q. The complete knowledge of the various cellular CoQ functions is essential to provide a rational basis for its possible therapeutic use, not only in diseases characterized by primary CoQ deficiency, but also in large number of diseases in which its secondary deficiency has been found.     

Where Are We with RPE Replacement Therapy? A Translational Review from the Ophthalmologist Perspective

The retinal pigmented epithelium (RPE) plays a pivotal role in retinal homeostasis. It is therefore an interesting target to fill the unmet medical need of different retinal diseases, including age-related macular degeneration and Stargardt disease. RPE replacement therapy may use different cellular sources: induced pluripotent stem cells or embryonic stem cells. Cells can be transferred as suspension on a patch with different surgical approaches. Results are promising although based on very limited samples. In this review, we summarize the current progress of RPE replacement and provide a comparative assessment of different published approaches which may become standard of care in the future.