Heavy metal uptake in the enological food chain

Determination of Metal Content by Inductively Coupled Plasma-Mass Spectrometry in Polish Red and White Wine Samples in Relation to Their Type, Origin, Grape Variety and Health Risk Assessment

The main objective of the research was to assess the influence of selected factors (type of wine, grape variety, origin, alcohol content and daily consumption) on the concentration levels of 26 elements in 53 Polish wine samples, also using chemometric analysis tools. Concentration of Al, As, B, Ba, Be, Cd, Co, Cr, Cu, Fe, Hg, Li, Mn, Ni, Pb, Sb, Se, Sr, Ti, V, Zn and Zr was analyzed by ICP-MS, while concentration of Ca, Na, K and Mg was determined by ICP-OES. White wines were characterized by higher concentrations of Al, As, Be, Ca, Co, Cu, Fe, Hg, Li, Mg, Na, Pb, Sb, Ti, V, Zn and Zr (mean values: 0.075-86,403 μg·L-1 in white wines, 0.069-81,232 μg·L-1 in red wines). Red wines were characterized by higher concentrations of Ba, Cd, Cr, K, Mn, Se and Sr (mean values: 0.407-1,160,000 μg·L-1 in white wines, 0.448-1,521,363 μg·L-1 in red wines). The results obtained for the health risk assessment indices, including the Target Hazard Quotient (THQ, mean values per glass of wine: 2.097 × 10-5 (Cr)-0.041 (B) in all wines), indicate that the analyzed elements do not show a potential toxic effect resulting from wine consumption. The chemometric analysis confirmed that elements such as Li, Ti, Ca, Mn, Sr, Ba, Zn, Mg, Cu, Se and B were closely related to local conditions and soil properties, and the presence of Fe, Cr, V and Pb was related to contamination of the soil.

Recent progress on the microbial mitigation of heavy metal stress in soybean: overview and implications

Plants are adapted to defend themselves through programming, reprogramming, and stress tolerance against numerous environmental stresses, including heavy metal toxicity. Heavy metal stress is a kind of abiotic stress that continuously reduces various crops' productivity, including soybeans. Beneficial microbes play an essential role in improving plant productivity as well as mitigating abiotic stress. The simultaneous effect of abiotic stress from heavy metals on soybeans is rarely explored. Moreover, reducing metal contamination in soybean seeds through a sustainable approach is extremely needed. The present article describes the initiation of heavy metal tolerance mediated by plant inoculation with endophytes and plant growth-promoting rhizobacteria, the identification of plant transduction pathways via sensing annotation, and contemporary changes from molecular to genomics. The results suggest that the inoculation of beneficial microbes plays a significant role in rescuing soybeans under heavy metal stress. They create a dynamic, complex interaction with plants via a cascade called plant-microbial interaction. It enhances stress metal tolerance via the production of phytohormones, gene expression, and secondary metabolites. Overall, microbial inoculation is essential in mediating plant protection responses to heavy metal stress produced by a fluctuating climate.

Grape By-Products as Feedstuff for Pig and Poultry Production

Grape by-products are exceptional options for replacement of conventional and unsustainable feed sources, since large amounts are generated every year from the winery industry. However, the majority is wasted with severe environmental and economic consequences. The present review aimed to evaluate the effects of grape by-products on pig and poultry growth performance. The most recent literature was reviewed using ScienceDirect and PubMed databases and the results of a total of 16 and 38 papers for pigs and poultry, respectively, were assessed. Fewer studies are documented for pig, but the incorporation of grape by-products up to 9% feed led to an improvement in growth performance with an increase in average daily gain. Conversely, lower levels (<3% feed) are needed to achieve these results in poultry. The beneficial effects of grape by-products on animal performance are mainly due to their antioxidant, antimicrobial, and gut morphology modulator properties, but their high level of cell wall lignification and content of polyphenolic compounds (e.g., tannin) limits nutrient digestion and absorption by monogastric animals. The use of exogenous enzymes or mechanical/chemical processes can provide additional nutritional value to these products by improving nutrient bioavailability. Overall, the valorization of grape by-products is imperative to use them as feed alternatives and intestinal health promoters, thereby contributing to boost circular agricultural economy.

Assessment of Physicochemical, Macro- and Microelements, Heavy Metals, and Related Human Health Risk from Organically, Conventionally, and Homemade Romanian Wines

From the consumers’ perspective, organic and homemade products have become more attractive than conventional ones. However, scientific data regarding the characteristics, properties, and composition of these products are scarce. This study assessed the elemental composition of organic, conventional, and homemade Romanian wines. The physicochemical composition, SO2 (free and total) and total concentration of macroelements, microelements, and heavy metals from nine wine regions containing 165 samples of white (38 organic/70 conventional/57 homemade), 67 red (22/31/14) and 7 rosé (2/2/3) wines were analyzed by inductively coupled plasma mass spectrometry. Dietary intake and target hazard quotient were also evaluated. The phytochemical and elemental compositions of the wine samples varied across regions and wine types. The highest levels of Ca, K, Fe and Al were detected in conventional wines, while homemade wines recorded high concentrations of Na, Mg, V, Ba and Rb. In the case of the rosé wine samples, the levels of trace elements and heavy metals were below the admissible limit. The estimated daily intake of a glass of wine provided less than 0.5% of the tolerable daily intake of the analyzed elements. No health concerns were identified. All wine samples can be safely consumed, regardless of the culture system used for production, and homemade wines are not of a lower quality than organic or conventional wines.

B, J.A. A, C. PDLR, J. GP, M. S, F.J. GN. Occurrence of some rare earth elements in vineyard soils under semiarid Mediterranean environment

A comprehensive investigation has been carried out into the concentrations of a range of REEs (neodymium Nd, cerium Ce, lanthanum La, yttrium Y, scandium Sc) in soils of vineyards belonging to the protected denomination of origin (PDO) Valdepeñas (Central Spain). The mean concentrations (expressed in mg kg^-1) are Ce 70.6, Nd 32.9, La 36.2, Y 21.6, and Sc 13.7 in surface horizons (Ap), while in subsurface horizons (Bt or Bw and some Ck), the values are Ce 67.6, Nd 31.8, La 34.4, Y 19.6, and Sc 13.9. The relative abundance in these soils is Ce > La > Nd > Y > Sc in both the surface and subsurface horizons. These values are close to, or slightly higher than, the regional levels but similar to national and global averages, although relatively high values have been detected at certain sampling points. Another aim was to explain the spatial variations in these elements within the territory under study. It was found that the spatial variations are due to the nature of the parent materials and the pedogenetic processes, although the sparse spatial distribution patterns with prominent anomalies are interpreted arising from anthropogenic sources (fertilization). However, these anomalies did not present any environmental risk in the studied zone.

Application of benchtop total-reflection X-ray fluorescence spectrometry and chemometrics in classification of origin and type of Croatian wines

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A low-power benchtop TXRF system was used for analysis of 70 wine samples.

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The metal content of K, Ca, Fe, Cu, Zn, Mn, Sr, Rb, Ba, Pb, Ni, Cr and V was estimated by chemometric methods.

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Mn, K, Ni, Sr, Rb and Ba were the main variables used to differentiate by wine type and origin.

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LDA showed good detection and prediction abilities with selected elements.

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Classification of origin and type of Croatian wines by chemometric tools.

The contents of selected metals (K, Ca, Fe, Cu, Zn, Mn, Sr, Rb, Ba, Pb, Ni, Cr and V) in 70 wine samples from Continental and Adriatic part of Croatia and different types of wine (red and white) were determined by TXRF. The aim of this study was to compare the elemental composition of wines from two different regions and to determine the discriminant ability of each variable and to indicate which variables discriminate between the four categories considered.

Principal component analysis and cluster analysis showed that K, Mn, Ba and Ni can be considered as the most important characteristics to distinguish between Continental red and white wines, Rb, Ni and Ba for Continental red and Adriatic red wines while Sr is the only metal that completely distinguishes the samples of each category. Finally, linear discriminant analysis showed good recognition (100%) and prediction abilities (96.43%) using these selected elements.

Mechanical pruning and soil organic amendments in vineyards of ‘Syrah’: effects on wine mineral composition

The interaction of mechanized pruning systems and soil organic amendment can affect vine vegetative and reproductive growth. However, since organic amendments supply several mineral elements, namely heavy metals, this study aimed to understand the effects of the interaction between these two practices on the mineral composition of wine. Two field trials were implemented in ‘Syrah’ vineyards in two Portuguese wine regions (Lisboa and Tejo). Mechanical hedge pruning was compared with hand spur pruning and four different organic amendments were tested: biochar, municipal solid waste compost, cattle manure and sewage sludge. The nitrogen (N), phosphorus (P) and potassium (K) wine contents were significantly reduced by mechanical pruning while calcium (Ca) and magnesium (Mg) contents were tendentially higher in this pruning system. Mechanical pruning also reduced the content of some minor elements, such as arsenic (As), molybdenum (Mo) and nickel (Ni). In 2014, the year with the higher reproductive growth, some other elements also decreased as a consequence of the mechanical pruning (gallium - Ga; lithium – Li; rubidium - Rb, thallium – Tl; yttrium - Y). Concerning the organic amendments, sewage sludge was associated with the wines with the lowest P and iron (Fe) content. Ca content was tendentially higher in municipal solid waste compost and sewage sludge treatments. Mechanical pruning and organic amendments had different effects on the mineral composition of wine, according to each specific element. However, the legal limits, recommended by OIV and established by European Union, as well as the technical limits, adopted by winemakers, were never exceeded and the interaction of both practices does not seem to be a problem in what concerns to the mineral composition of the produced wines.

Multi-Indices Assessment of Origin and Controlling Factors of Trace Metals in River Sediments from a Semi-Arid Carbonated Basin (the Sebou Basin, Morocco)

River water quality is particularly of concern in semi-arid countries with limited water resources. Increasing anthropogenic activities can lead to the accumulation of trace metals (TM) in bottom sediments, which is a specific storage compartment. The present study aimed to investigate the geochemistry of trace metals (As, Cd, Co, Cr, Cu, Ni, Pb, Zn) and of some physico-chemical parameters in bottom sediments from the Sebou basin, which represents 1/3 of the surface water resources of Morocco. The order of abundance of the metals was Zn > Cr > Cu > Ni > Pb > Co > As > Cd. A major fingerprint of weathering on metal concentration, and point and non-point anthropogenic sources were highlighted. The origin and intensity of the contamination were determined using a combination of geochemical indicators. The contamination was on the whole moderate, with Cr, Zn, Cu, and Pb as the most enriched metals, especially at the A1, S3, and S4 stations located downstream of Fez city, well known for its intensive industrial and tannery activities. A multi-variate analysis evidenced the strong link between natural elements such as Co with clays and Fe oxides, and As with Ca, whereas Cd, Cu, Cr, Ni, Pb, Zn, partly originating from anthropogenic activities (industrial and domestic waste, agricultural inputs), were linked to phosphorus, oxides, carbonates, and/or POC, indicating their anthropic source and/or control by sediment compounds. Cadmium, Pb, and Cu were the most available metals. Finally, in addition to Cd, Pb and Zn were identified as hazardous metals in sediments as evidenced by the positive relationship between the proportion of the labile fraction and the enrichment factor revealing anthropogenic inputs.

Elemental composition, rare earths and minority elements in organic and conventional wines from volcanic areas: The Canary Islands (Spain)

The organic wine market is rapidly growing worldwide, both in terms of production and consumption. However, the scientific literature is not conclusive regarding differences in the elemental composition of wines according to their production method, including both major and trace elements. Minerals can be present in wine as a result of both anthropogenic and environmental factors. To date, this has not been evaluated in volcanic contexts, neither has the emergent issue of rare earths and other minority elements as potential sources of food contamination. This study using inductively coupled plasma mass spectrometry (ICP-MS) analyses organic and conventional wines produced in the Canary Islands (Spain), an archipelago of volcanic origin, to compare their content of 49 elements, including rare earths and minority elements. Our results showed that organic wines presented lower potential toxic element content on average than their conventional counterparts, but differences were not significant. Geographical origin of the wine samples (island) was the only significant variable differentiating wine samples by their composition profiles. By comparing our data with the literature, no agreement was found in terms of differences between organic and conventionally-produced wines. This confirms that other factors prevail over elemental composition when considering differences between wine production methods. Regarding the toxicological profile of the wines, five samples (three organic and two conventional) exceeded the maximum limits established by international legislation. This highlights the need for stricter analytical monitoring in the Canary Islands, with a particular focus on Cu and Ni concentration, and potentially in other volcanic areas.

Measurement and ecological risk assessment of heavy metals accumulated in sediment and water collected from Gomishan international wetland, Iran

This study aimed to measure and ecologically assess heavy metals, including As, Cr, Pb, Cd, and Ni in water and sediment samples taken from Gomishan, an international wetland located in Golestan, Iran. Four sampling stations were selected to cover all parts of the wetland. The analyses of the heavy metals were performed by ICP-MS. Based on the content of the heavy metals in the sediments, the values of risks for individual heavy metals, as Er, and for total heavy metals, as IR, were estimated. Igeo and EF also presented the soil quality in terms of accumulated contamination. The average content of the heavy metals in water was 23.12, 4.14, 10.04, 6.71, and 94.48 μg/L for As, Cd, Cr, Ni, and Pb, respectively. The heavy metal concentrations in sediments were decreased in the following order: Pb (2130 ppb) > As (655 ppb) > Cr (295 ppb) > Ni (148.8 ppb) > Cd (148.8 ppb). The potential risk values for individual heavy metals were in the low range, Er < 40, except for Cd, which mostly posed a moderate ecological risk. The values of EF and Igeo showed that the sediments sampled from the Gomishan wetland were minimally enriched and contaminated. As the Gomishan wetland has a moderate risk of heavy metal contamination, conservative and monitoring activities should be performed.

ICP–MS Analysis of Multi-Elemental Profile of Greek Wines and Their Classification According to Variety, Area and Year of Production

Major, minor and trace elements in wines from Greece were determined by inductively coupled plasma–mass spectrometry (ICP–MS). The concentrations of 44 elements (Na, Mg, P, K, Ca, Cu, Co, Cr, Zn, Sn, Fe, Mn, Li, Be, B, V, Sr, Ba, Al, Ag, Ni, As, Sn, Hg, Pb, Sb, Cd, Ti, Ga, Zr, Nb, Pd, Te, La, Sm, Ho, Tm, Yb, W, Os, Au, Tl, Th, U) in 90 white and red wines from six different regions in Greece for two consecutive vinification years, 2017 and 2018, were determined. Results for the elements aforementioned were evaluated by multivariate statistical methods, such as discriminant analysis and cluster analysis, and the wines were discriminated according to wine variety and geographical origin. Due to the specific choice of the analytes for multivariate statistical investigation, a prediction rate by cross-validation of 98% could be achieved. The aim of this study was not only to reveal specific relationships between the wine samples or between the chemical variables in order to classify the wines from different regions and varieties according to their elemental profile (wine authentication), but also to observe the annual fluctuation in the mineral content of the studied wine samples.

Metal concentrations of wild mushroom species collected from Belgrad forest (Istanbul, Turkey) with their health risk assessments

Wild edible mushrooms are very popular for both their flavors and nutritional values. However, some mushroom species can be harmful to human health as they accumulate some elements in excessive amounts. The aim of this study was to determine the concentrations of Al, Ca, Cd, Cr, Cu, Fe, K, Mg, Mn, P, Se, and Zn of some wild edible (Agaricus arvensis, A. bitorquis, A. sylvaticus, Amanita vaginata, Armillaria mellea, Clavariadelphus pistillaris, Clitocybe nebularis, Clitopilus prunulus, Hygrophorus marzuolus, H. russula, Lactarius volemus, Lycoperdon molle, and Macrolepiota mastoidea) and non-edible mushroom species (A. citrina, Auricularia mesenterica, Chanterellus melanoxeros, Chondrostereum purpureum, Clathrus ruber, L. controversus, L. helvus, and L. zonarius) collected from Belgrad forest (Istanbul, Turkey). Daily intakes of element (DIE) and health risk index (HRI) values of the edible mushroom species were also calculated. The concentrations of the elements in question were determined to be in the ranges of 9.7-556.8, 2.5-2226.7, 0.06-2.52, 0.03-13.17, 3.74-100.19, 13.3-507.4, 2635.0-28614.0, 493.0-2412.0, 6.97-3150.73, 0.29-13.26, 0.38-3.67, and 9.1-293.8 mg/kg, respectively. The Cd concentration of H. russula (DIE: 1.08, HRI: 1.08), Cr concentration of C. nebularis (DIE: 5.64, HRI: 1.88), and the Cu concentration of M. mastoidea (DIE: 42.94, HRI: 1.07) were above the reference values. The results showed that the long-term consumption of H. russula, C. nebularis, and M. mastoidea collected from Belgrad forest can have a negative impact on human health. Therefore, it was concluded that the element concentrations of edible wild mushrooms in this region should be examined periodically.

Reproducibility of elemental profile across two vintages in Pinot noir wines from fourteen different vineyard sites

The reproducibility of elemental profile in wines produced across vintages of 2015 and 2016 has been studied using grapes from a single scion clone of Vitis vinifera L. cv. Pinot noir. Grapevines were grown on fourteen different vineyard sites, from Oregon to southern California in the U.S.A., which span distances from approximately hundreds of meters to 1450 km, while elevations range from near sea level to nearly 500 m. The number of elements quantified in the wines made from the 2016 vintage was thirty, by using inductively coupled plasma mass spectrometry (ICP-MS). These data were compared with the twenty-seven elements quantified and previously reported in wines made from 2015 vintage, including twenty-four elements reported in both vintages. The composition of each element was analyzed by analysis of variance with main effect of vineyard. Wines were classified according to vineyard origin and environmental growing site with a combination of factors correlated with the wine elemental profile. The low variability (< 25%) of certain elements in wines from at least eight sites across both vintages, including Group 1 (Cs, K, Na and Rb), Group 2 (Ba, Ca, Mg and Sr), Group 3B (Eu), Group 13 (Al, B and Ga), Group 15 (As and P) and Co, Fe, Mn, Ni and V, demonstrated the reproducibility over the seasons analyzed (2015 and 2016). The comparison of elemental profile of wines across growing seasons demonstrates the opportunity to reproduce one key aspect of wine chemistry across vintages.

Impaired follicular development and endocrine disorders in female rats by prepubertal exposure to toxic doses of cadmium

Cadmium (Cd) has been associated with several physiological problems including reproductive and endocrine system dysfunction resulting in temporary infertility. The principal objective of this project was to investigate the effects of prepubertal exposure to toxic doses of Cd on puberty onset, the endocrine system, and follicular development. For this purpose, 16 female Sprague-Dawley rats weaned on postnatal day (PND) 21 were randomly divided into 4 groups (n = 4 per group). The treatments were as follows: 0, 25, 50, and 75 mg/kg/day of cadmium chloride (CdCl₂) by oral gavage from PND 21 to observation of first vaginal opening (VO). The results demonstrated that prepubertal exposure to different doses of CdCl₂ delays the age of VO, first diestrus, and first proestrus via altering the concentrations of estradiol and progesterone. The low level of these steroid hormones contributed to lower differentiation and maturation of follicles and it finally led to reduced ovarian reservoir of follicles and impaired follicular development. The number of atretic follicles and secondary follicles with premature cavity increased in rats that received a high dose of CdCl₂, whereas the number of secondary follicles and corpora luteum decreased in the same circumstances. Taken together, these data suggest that prepubertal exposure to toxic doses of Cd delays the onset of puberty via disorderliness in the concentration of steroid hormones and reduces the ovarian reservoir of follicles, as well as folliculogenesis.

Preliminary Study of Microelements, Phenolics as well as Antioxidant Activity in Local, Homemade Wines from North-East Greece

The present study is aimed to analyze the composition of microelements in wines prepared by amateur winemakers in Drama region (recognized as Protected Geographical Indication (PGI)), especially the toxic ones, as well as the phenolic content and antioxidant activity of these wines since moderate wine consumption may contribute to health benefits to the consumers. A total of twenty-four wines, comprising sixteen red and eight white, were tested. The micro and macroelements were determined with ICP-OES (Inductively coupled plasma-optical emission spectrometry). Chromatic characteristics of wines and total phenolic and flavonoid compounds as well as their antioxidant activity with three different assays were determined spectrophotometrically. The amateur’s wines showed levels of contaminants with toxic metals less than the limits set from the International Organization of Vine and Wine (OIV). Moreover, toxic metals concentrations were comparable to those of European wines. The Principal Component Analysis discriminated wines into white and red and further distinguished the red wine into two groups depending on the Total Flavonoid content, antioxidant activity and color intensity. The moderate consumption of amateur wines can be recommended since their consumption is not harmful to the health, and they contain high amount of phenolics and flavonoids comparable or even higher to that of commercial wines.

Fuzzy Divisive Hierarchical Associative-Clustering Applied to Different Varieties of White Wines According to Their Multi-Elemental Profiles

Wine data are usually characterized by high variability, in terms of compounds and concentration ranges. Chemometric methods can be efficiently used to extract and exploit the meaningful information contained in such data. Therefore, the fuzzy divisive hierarchical associative-clustering (FDHAC) method was efficiently applied in this study, for the classification of several varieties of Romanian white wines, using the elemental profile (concentrations of 30 elements analyzed by ICP-MS). The investigated wines were produced in four different geographical areas of Romania (Transylvania, Moldova, Muntenia and Oltenia). The FDHAC algorithm provided not only a fuzzy partition of the investigated white wines, but also a fuzzy partition of considered characteristics. Furthermore, this method is unique because it allows a 3D bi-plot representation of membership degrees corresponding to wine samples and elements. In this way, it was possible to identify the most specific elements (in terms of highest, smallest or intermediate concentration values) to each fuzzy partition (group) of wine samples. The chemical elements that appeared to be more powerful for the differentiation of the wines produced in different Romanian areas were: K, Rb, P, Ca, B, Na.

Effects of short- and long-term exposure to cadmium on salivary glands and fat body of soil centipede Lithobius forficatus (Myriapoda, Chilopoda): Histology and ultrastructure

Cadmium (Cd) is the most widely studied heavy metal in terms of food-chain accumulation and contamination because it can strongly affect all environments (e.g., soil, water, air). It can accumulate in different tissues and organs and can affect the organism at different levels of organization: from organs, tissues and cells though cell organelles and structures to activation of mechanisms of survival and cell death. In soil-dwelling organisms heavy metals gather in all tissues with accumulation properties: midgut, salivary glands, fat body. The aim of this study was to describe the effects of cadmium on the soil species Lithobius forficatus, mainly on two organs responsible for gathering different substances, the fat body and salivary glands, at the ultrastructural level. Changes caused by cadmium short- and long-term intoxication, connected with cell death (autophagy, apoptosis, necrosis), and the crosstalk between them, were analyzed. Adult specimens of L. forficatus were collected in a natural environment and divided into three experimental groups: C (the control group), Cd1 (cultured in soil with 80 mg/kg of CdCl₂ for 12 days) and Cd2 (cultured in soil with 80 mg/kg of CdCl₂ for 45 days). Transmission electron microscopy revealed ultrastructural alterations in both of the organs analyzed (reduction in the amount of reserve material, the appearance of vacuoles, etc.). Qualitative analysis using TUNEL assay revealed distinct crosstalk between autophagy and necrosis in the fat body adipocytes, while crosstalk between autophagy, apoptosis and necrosis in the salivary glands was detected in salivary glands of the centipedes examined here. We conclude that different organs in the body can react differently to the same stressor, as well as to the same concentration and time of exposure. Different mechanisms at the ultrastructural level activate different types of cell death and with different dynamics.

Vineyard site impact on the elemental composition of Pinot noir wines

Elemental composition was used to characterize and differentiate 14 wines made from the identical clone of Vitis vinifera cv. Pinot noir (clone 667). The vineyards span distances which range from several hundred meters to 1540 km and their elevations vary from near sea level to nearly 500 m. Twenty-seven elements were observed above the limit of quantitation by using inductively coupled plasma mass spectrometry (ICP-MS) in the wines from at least half of the 14 sites. Concentrations of several elements, including Mo, Er, Na, Li, Cs and Pb, varied by 10-fold across the 14 wines. Multiple factor analysis (MFA) of elemental composition with juice chemistry and site characterization show associations consistent with expectations, such as high Ca with high clay content. These results demonstrate that even when grapevine clone and winemaking protocol are controlled, composition differences in wines produced from sites are mediated by diverse soil and microclimate conditions.

Assessment of the Heavy Metal Accumulation of Various Green Vegetables Grown in Nevşehir and their Risks Human Health

This study aimed to investigate the accumulation of heavy metal in five different leafy green vegetables grown in 10 different agricultural lands in the province of Nevşehir, Turkey, and determine the human health risks that may arise as a result the consumption of such metals. The heavy metal concentrations found in the soil samples taken from the agricultural lands were as follows: manganese (Mn) > lead (Pb) > arsenic (As) > nickel (Ni) > copper (Cu) > cadmium (Cd). These concentrations were found to be well above the permitted limits imposed by the World Health Organization/Food and Agricultural Organization (WHO/FAO) and the United States Environmental Protection Agency (USEPA). Also, particularly the concentrations of Pb and As were found to be dangerous levels in the soil. According to their accumulation in the vegetables, the detected heavy metal concentrations were listed as Mn > Zn > Cu > Ni > As > Cd. The estimated daily intake amount of the heavy metals was also found to be higher than the limits determined by FAO/WHO. Furthermore, the target hazard quotient of the metals was Mn > As > Cu > Zn > Ni > Cd > Pb. It was found to be > 1 for the sampling areas, except for Cd and Pb. As a result of the study, it was determined that almost all of the annual heavy metal intake amount that the population living in this region should receive was met as a result of the consumption of leafy vegetables grown in the stations designated for this study. It is vital to effectively monitor the heavy metal in the soil and vegetables to reduce metal concentrations in the studied area and to investigate its effects on human health. By doing so, acute and chronic health problems due to the heavy metal exposure in this region can be prevented.

The Use of Macro, Micro, and Trace Elemental Profiles to Differentiate Commercial Single Vineyard Pinot noir Wines at a Sub-Regional Level

The compositional authentication of wine is of great interest, as the geographic origin of the grapes is often associated with quality, uniqueness, and authenticity. Previous elemental fingerprinting studies mainly discriminated wines from different countries or regions within a country. Here, we report the use of element profiles to distinguish commercial Pinot noir wines from five sub-regional appellations or neighborhoods within one American viticultural area (AVA). Fifty-three single cultivar wines were collected over two harvests and analyzed using microwave plasma-atomic emission spectroscopy (MP-AES) and inductively coupled plasma-mass spectrometry (ICP-MS). Of 62 monitored elements that were quantified with fully validated methods, 24 and 32 elements differed significantly across the neighborhoods and vintages, respectively (p < 0.05). Targeted canonical variate analysis (CVA) explained 85–90% of the variance ratio across the two vintages, indicating persistent and stable elemental fingerprints of wines at a sub-regional level. A sixth, newly founded neighborhood was correctly grouped separately from the others using a Soft Independent Modeling of Class Analogy (SIMCA), indicating the potential of elemental fingerprints for wine authenticity.

How to Deal with Uninvited Guests in Wine: Copper and Copper-containing Oxidases

Copper is one of the most frequently occurring heavy metals in must and wine. It is introduced by pesticides, brass fittings, and as copper sulphate for treatment of reductive off-flavors. At higher concentrations, copper has harmful effects on the wine. It contributes to the oxidation of wine ingredients, browning reactions, cloudiness, inhibition of microorganisms, and wine fermentation. Last but not least, there is also a danger to the consumer. At present, some physicochemical methods exist to reduce the copper content in must and wine, but they all have their shortcomings. A possible solution is the biosorption of metals by yeasts or lactobacilli. Copper can also reach must and wine in the form of copper-containing phenol oxidases (grape tyrosinase, Botrytis cinerea laccases). Similar to free copper, they oxidize phenolic wine compounds, and thus lead to considerable changes in color and nutritional value, making the product ultimately unsaleable. All measurements for enzyme inactivation such as heat treatment, and addition of sulphites or bentonite are either problematic or not effective enough. The application of oenological tannins could offer a way out but needs further research.

Quantification of manganous ions in wine by NMR relaxometry

Proton relaxation in model and real wines is investigated for the first time by fast field cycling NMR relaxometry. The relaxation mechanism unambiguously originates form proton interaction with paramagnetic ions naturally present in wines. Profiles of a white Chardonnay wine from Burgundy, a red Medoc, and model wines are well reproduced by Solomon-Bloembergen-Morgan equations. Relaxation is primarily governed by interactions with Mn²⁺. A straightforward model-independent quantification of the manganese ion concentration (down to few tens of μg/L) is proposed.

Heavy Metals Distribution, Sources, and Ecological Risk Assessment in Huixian Wetland, South China

This research has focused on the source identification, concentration, and ecological risk assessment of eight heavy metals in the largest karst wetland (Huixian) of south China. Numerous samples from superficial soil and sediment within ten representative landuse types were collected and examined, and the results were analyzed using multiple methods. Single pollution index (Pi) results were underpinned by the Geoaccumulation index (Igeo) method, in which Cd was observed as the priority pollutant with the highest contamination degree in this area. As for the most polluted landuse type, via applying Nemerow’s synthetical contamination index (PN) and Potential ecological risk index (RI), the river and rape field posed the highest ecological risks, while moderate for the rest. To quantify the drivers of the contaminants, a principal component analysis (PCA) was carried out and weathering of the watershed’s parent carbonate rocks was found to be the main possible origin, followed by anthropogenic sources induced by agricultural fertilizer. Considering the impacts of these potentially toxic elements on public health, the results of this study are essential to take preventive actions for environmental protection and sustainable development in the region.

Mineral composition of organic and conventional white wines from Italy

Despite of the increased interest of consumers for organic agro-food products and of the growing demand for organic wines, scientific literature reports a limited number of studies aimed to evaluate the chemical composition of organic wine with respect to conventional wine in terms of major and trace metals. In the present study the concentrations of 19 elements (Al, As, B, Ca, Cd, Co, Cr, Cu, Fe, K, Li, Mg, Mn, Na, Ni, Pb, Sr, V, and Zn) were determined in samples of white wines from Italy, conventionally and organically produced. No significant difference in the mineral composition was found between the two groups, except for Ni, which showed a higher concentration in organic wines. By comparing our data with data from literature it can be pointed out that there is no agreement among the results presented in the different studies referring to comparisons between organically and conventionally produced wines, concluding that the mineral composition of wines depends on factors different from organic/conventional production method.

Geographical origin of Vitis vinifera cv. Cannonau established by the index of bioaccumulation and translocation coefficients

Geochemical fingerprints in grape require an identification of major and trace elements that show correlations between concentrations in soil and in plant tissues: these correlations are relevant to discriminate grapes according to geographical origin. The Vitis vinifera cultivar Cannonau is used to produce the renowned Italian controlled designation of origin (DOC) wine "Cannonau" from Sardinia. Two Cannonau vineyards located in Sardinia Region were studied to establish the relationship between geochemical features of vineyard soil and chemical composition of leaves and grape berries. Major and trace elements were determined by X-ray fluorescence and inductively coupled plasma-mass spectrometry in soil, leaf, and grape berry samples. The index of bioaccumulation and the translocation coefficients were also calculated for all elements. Data from the two study areas were compared by a non-parametric test and multivariate statistics (principal component analysis). The results showed a specific assimilation of these elements in leaf and grape berry from vine in two different soils. Moreover, geochemical characterization and statistical analysis enabled to discriminate the cultivar "Cannonau" according to geographical origin. The results showed that the elements that could establish a reliable correlation between the soil vineyard and leaves and grape berries from the two study areas were B, Sr, and Zr. These elements may therefore be used as geochemical fingerprints to identify the geographic origin of V. vinifera cv. Cannonau in the two study areas.

Variation of heavy metal contamination between mushroom species in the Copperbelt province, Zambia: are the people at risk?

BACKGROUND

Heavy metal contamination in mushrooms and the associated health risk are unknown in Zambia. We studied seven heavy metals and 23 mushroom species and interviewed 400 people.

RESULTS

Mushrooms were found to contain substantial concentrations of Cu (894.4 ± 267.9 µg g^-1 ) and Fe (998.4 ± 454.0 µg g^-1 ). Significant differences in transfer factors of metals occurred between mushroom species (F_11,66  = 5.36, P < 0.001). The most efficient were L. kabansus (for Zn and Ni), A. miomboensis (for Cu and Fe) and T. clypeatus (for Mn, Pb and Co). These species were also among the most preferred mushrooms for consumption based on the interviews conducted. Although 60% of the mushrooms observed were edible, only 20% were frequently consumed during the mushroom season. High positive correlations observed between soils and mushrooms suggest that contamination in mushrooms increases with soil pollution. The estimated daily intake of metals and the target hazard quotient through mushroom consumption were found to be significantly influenced by mushroom species (F_11,66  = 38.8, P < 0.001) suggesting that the level of exposure to heavy metals depends on the species of mushroom consumed.

CONCLUSIONS

The study has revealed that heavy metal concentrations in mushrooms exceed permissible limits and vary between species. Transfer efficiency also varies between mushroom species and contamination in mushrooms increases with soil pollution. The fact that concentrations of metals in soil were significantly high, the risk of exposure through mushroom consumption and possibly soil ingestion is even higher. © 2019 Society of Chemical Industry.

Subcellular distribution, chemical forms and physiological responses involved in cadmium tolerance and detoxification in Agrocybe Aegerita

A pot experiment was conducted to investigate the detoxification mechanism of Agrocybe aegerita (A. aegerita). The physiological responses, subcellular distribution and chemical forms of cadmium (Cd) in A. aegerita grown in Cd stress were analyzed. The results showed that the biomass was decreased under Cd stress, while the production of malonaldehyde, thiols, and low-molecular-weight organic acids (LWMOAs) as well as the antioxidant enzymes in A. aegerita was increased compared with control group. The HPLC results showed that nine LWMOAs were found in A. aegerita with critic acid as the dominant and they played important role in the detoxification and accumulation of Cd in A. aegerita. More Cd was accumulated in pileus than in stipe. Differential centrifugation technique showed that the majority of Cd was compartmentalized in the soluble fraction (53-75%) and bound to the cell wall (19-42%). The proportion of Cd in the cell wall increased with the increase of the accumulation of Cd in the fruiting body, but in the soluble fraction showed an opposite trend. Furthermore, most of the Cd in A. aegerita was mainly in the forms of NaCl- (29-49%) and ethanol-extractable Cd (20-40%). The ethanol- and water-extractable Cd in stipe (60-66%) was higher than in pileus (43-49%). Thus intracellular detoxification mechanisms of Cd in A. aegerita is related to subcellular partitioning and chemical forms of Cd and well-coordinated physiological responses.

Changes in Metal Ion Concentrations in a Chardonnay Wine Related to Oxygen Exposure during Vinification

The impact of oxygen exposure during winemaking on metal ion concentrations in wine were investigated throughout the winemaking process in a Chardonnay wine. The concentrations of Al, Ca, Co, Cr, Cu, Fe, K, Mg, Mn, Na, Ni, Sn, and Zn were determined using inductively coupled plasma-mass spectrometry. Oxygen exposure significantly impacted 13 metal ions at different phases of winemaking. However, only the concentrations of Cr, Cu, and Fe were impacted by early oxygen exposure during pressing, with lower Cr and Cu concentrations in wines that were aerobically pressed and lower concentrations of Fe in wines that were inertly pressed. The sequestering of Al, Cu, Ni, and Zn by wine lees was significantly affected by oxygen treatment, with lees collected from wines that were treated oxidatively sequestering significantly greater amounts of Cu and Zn and removing these metals from the wine supernatant. The metal ion that was most affected by oxygen exposure during pressing and handling was Cu, with significantly lower Cu measured in wines that were produced under oxidative conditions. It is known that elevated Cu concentrations have negative implications for wine aroma and flavour. This study demonstrated that oxygen management during winemaking significantly impacts metal ion concentrations in lees and wine, which may decrease the risk of developing taints and faults.

Direct Determination of Zn, Cd, Pb and Cu in Wine by Differential Pulse Anodic Stripping Voltammetry

Metals in wine can originate from natural and anthropogenic sources and their concentrations have significant effects on wine proprieties as well in its conservation. In this work, direct and simultaneous determinations of Zn, Cd, Pb and Cu in wine samples were carried out by differential pulse anodic stripping voltammetry without any steps of previous pretreatment. The samples analyzed presented concentration levels from 4.64 to 69.3 µg L−1 of Zn, from 1.74 to 5.25 µg L−1 of Cd, from 4.57 to 17.9 µg L−1 of Pb and from 1.0 to 10.3 µg L−1 of Cu. Accuracy was evaluated with the standard addition method and recoveries ranged from 82.5 and 130.8% for Zn, from 85.7 to 107.0% for Cd, from 89.7 to 101.0% for Pb and from 81.4 to 105.9% for Cu. With the application of this method, it was possible to quantify the metals in a simple and easy way not requiring sample preparation or other approaches for the destruction of organic substances.

Mineral Composition through Soil-Wine System of Portuguese Vineyards and Its Potential for Wine Traceability

The control of geographic origin is one of a highest priority issue regarding traceability and wine authenticity. The current study aimed to examine whether elemental composition can be used for the discrimination of wines according to geographical origin, taking into account the effects of soil, winemaking process, and year of production. The elemental composition of soils, grapes, musts, and wines from three DO (Designations of Origin) and for two vintage years was determined by using the ICP-MS semi-quantitative method, followed by multivariate statistical analysis. The elemental composition of soils varied according to geological formations, and for some elements, the variation due to soil provenance was also observed in musts and wines. Li, Mn, Sr and rare-earth elements (REE) allowed wine discrimination according to vineyard. Results evidenced the influence of winemaking processes and of vintage year on the wine’s elemental composition. The mineral composition pattern is transferred through the soil-wine system, and differences observed for soils are reflected in grape musts and wines, but not for all elements. Results suggest that winemaking processes and vintage year should be taken into account for the use of elemental composition as a tool for wine traceability. Therefore, understanding the evolution of mineral pattern composition from soil to wine, and how it is influenced by the climatic year, is indispensable for traceability purposes.

Geochemical fingerprints of "Prosecco" wine based on major and trace elements

The terroir can be defined as interactive ecosystem that includes climate, geology, soil and grapevine, and it is used to explain the hierarchy of high quality of wine. In order to understand the terroir functions, it is necessary to analyse the interactions among the geology, soil and wine. To define a geochemical fingerprint, the relationship between geochemistry of vineyard soil and chemical composition of wine from Veneto Italian Region was studied. The vineyards tested belonged to four distinct wineries located in the Veneto alluvial plain, included in the Controlled Designation of Origin (DOC) area of Prosecco. We investigated the relationship between major and trace elements in soil and their concentrations in Prosecco wine according to geographical origin. The detection of chemical composition in soil and wine were analysed by inductively coupled plasma mass spectrometry, and data were elaborated by nonparametric test and multivariate statistics Linear Discrimination Analysis. The geochemical and statistical analyses allowed to discriminate the vineyard soils according to geo-lithological characteristics of each area and to identify the geochemical "Prosecco" fingerprints, useful against fraudulent use of DOC wine labels.

Arsenic and trace elements in soil, water, grapevine and onion in Jáchal, Argentina

Contamination by trace elements (TE) is an increasing concern worldwide. In some areas, crop production could be limited by the presence of metals and metalloids, so it is important to determine their concentrations and mobility. The region of Jáchal, province of San Juan, Argentina, has good growing conditions for onion and grapevine production, but their quality and yield are affected by high TE concentration in soils and water. Soils, water, grapevine and onion were sampled and TE content determined. In soils elevated As, B, Cr, Hg, and Tl concentrations were detected (506±46, 149±3, 2714±217, 16±7, and 12±3μgg^-1, respectively, for maximum values measured), and physicochemical properties of the soil promotes these elements mobility. Water samples had high As, B, Cr, and Fe concentrations (1438±400, 10,871±471, 11,516±2363, and 3071±257μgL^-1, respectively, for maximum values measured) while in onion bulbs and grapevine berries, As, Cr, Cu, and Fe (92±7 and 171±20, 1412±18 and 2965±32, 17±3 and 126±88, and 418±204 and 377±213μgg^-1, respectively, for maximum values measured) exceeded the limits for food consumption established by Argentinian law. Correlation analyses indicated that: i) there is a common source of TE in this area, ii) each elements concentration in plants is associated with different soil variables and different soils depths, and iii) the lack of correlation between soil and water indicates that concentration in water is not constant over the time and/or there exists a differential accumulation of elements in soils depending on their own properties. Data obtained demonstrate very high concentration of TE in soil, grapevines, and onion plants in Jáchal region, and different remediation techniques are necessary to stabilize and minimize the bioavailability of these elements.

Chemical elements as fingerprints of geographical origin in cultivars of Vitis vinifera L. raised on the same SO4 rootstock

The uptake of major and trace elements in grapevine (Vitis vinifera L.) can be influenced by soil, climate, geographic origin, and rootstock type. Rootstocks were mainly selected to resist phylloxera and for specific tolerance to lime, mineral uptake, drought, and salinity. The relationship among concentrations of major, trace, and rare earth elements was studied in soil and leaves from two Italian grapevine cultivars, "Cabernet Sauvignon" and "Corvina," employed to produce renowned controlled designation of origin (DOC) wines. The cultivars were raised on the same rootstock SO4 in two different areas of the Veneto Region (Northern Italy). The elements were studied by X-ray fluorescence and inductively coupled plasma mass spectrometry, and data were elaborated by non-parametric tests and multivariate linear discrimination analysis. The related index of bioaccumulation was calculated to define the specific assimilation of the elements from soil to leaves. A statistically significant correspondence between soil and leaf samples was observed for Mg, Sm, V, and Zr. The results allowed to discriminate soil and leaf samples of the two cultivars according to geographical provenance, possibly providing geochemical markers (fingerprints) useful against fraudulent use of DOC wine labels.

Effects of subchronic oral toxic metal exposure on the intestinal microbiota of mice

Oral exposure to toxic metals such as cadmium (Cd), lead (Pb), copper (Cu) and aluminum (Al) can induce various adverse health effects in humans and animals. However, the effects of these metals on the gut microbiota have received limited attention. The present study demonstrated that long-term toxic metal exposure altered the intestinal microbiota of mice in a metal-specific and time-dependent manner. Subchronic oral Cu exposure for eight weeks caused a profound decline in gut microbial diversity in mice, whereas no significant changes were observed in groups treated with other metals. Cd exposure significantly increased the relative abundances of organisms from the genera Alistipes and Odoribacter and caused marked decreases in Mollicutes and unclassified Ruminococcaceae. Pb exposure significantly decreased the abundances of eight genera: unclassified and uncultured Ruminococcaceae, unclassified Lachnospiraceae, Ruminiclostridium_9, Rikenellaceae_RC9_gut_group, Oscillibacter, Anaerotruncus and Lachnoclostridium. Cu exposure affected abundances of the genera Alistipes, Bacteroides, Ruminococcaceae_UCG-014, Allobaculum, Mollicutes_RF9_norank, Rikenellaceae_RC9_gut_group, Ruminococcaceae_unclassified and Turicibacter. Al exposure increased the abundance of Odoribacter and decreased that of Anaerotruncus. Exposure to any metal for eight weeks significantly decreased the abundance of Akkermansia. These results provide a new understanding regarding the role of toxic metals in the pathogenesis of intestinal and systemic disorders in the host within the gut microbiota framework.

Effects of Copper Pollution on the Phenolic Compound Content, Color, and Antioxidant Activity of Wine

The effects of copper pollution on the polyphenol content, color, and antioxidant activity of wine, as well as correlations among these factors, were investigated. Copper had clear influences on wine polyphenol content. At low copper concentrations, the concentrations of nearly all polyphenols increased, and the antioxidant activity values of the wine also increased. When the copper concentration reached the lowest level of the medium copper range (9.6~16 mg/L), most of the indices also improved. When the copper concentrations reached the latter part of the medium copper range (19.2 and 22.4 mg/L), many of the tested indices began to decrease. Furthermore, when the copper concentration reached the high ranges (32, 64, and 96 mg/L), the polyphenol content, CIELAB color parameters, and antioxidant activity of wine were substantially decreased, indicating the need to control increasing copper content in grape must.

Evaluation of groundwater and surface water quality and human risk assessment for trace metals in human settlements around the Bosomtwe Crater Lake in Ghana

Geogenic and anthropogenic activities introduce certain metals into the environment which tend to deteriorate the quality of both surface and groundwater in the Bosomtwe Crater Lake and its surroundings. In this study spatio-temporal variations in concentrations and risk assessment of selected trace metals (As, Fe, Pb, Zn, Cr, Cd and Ni) were investigated during the wet and dry seasons for surface and groundwater in selected human settlements around the lake. The levels of As, Cd and Ni were generally small and were below the detection limit of the instrument. The results showed no significant seasonal variations in the mean levels of Pb, Fe, Zn and Cr in water from the Bosomtwe Crater Lake. The hazard quotients and health hazard indices through ingestion and dermal contact of lake and groundwater in towns around the lake for both adults and children gave values which were below the acceptable limit of less than unity (< 1), indicating the absence of non-carcinogenic health risk to the communities. The study however reveals that ingestion of both lake and groundwater from the lake and its surroundings poses carcinogenic risk with regard to the level of Pb and Cr. Hence appropriate control measures and interventions should be put in place to protect the health of the human population in the study area.

Protective Effects of Lactobacillus plantarum CCFM8246 against Copper Toxicity in Mice

Lactobacillus plantarum CCFM8246, which has a relatively strong copper binding capacity and tolerance to copper ions, was obtained by screening from 16 lactic acid bacteria in vitro. The selected strain was then applied to a mouse model to evaluate its protective function against copper intoxication in vivo. The experimental mice were divided into an intervention group and a therapy group; mice in the intervention group received co-administration of CCFM8246 and a copper ion solution by gavage, while mice in the therapy group were treated with CCFM8246 after 4 weeks of copper exposure. In both two groups, mice treated with copper alone and that treated with neither CCFM8246 nor copper served as positive and negative controls, respectively. At the end of the experimental period, the copper content in feces and tissues, the activity of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) in serum, and oxidation stress indices in liver and kidney tissue were determined. Learning and memory ability was evaluated by Morris water maze experiments. The results indicated that treatment with CCFM8246 significantly increased the copper content in feces to promote copper excretion, reduce the accumulation of copper in tissues, reverse oxidative stress induced by copper exposure, recover the ALT and AST in serum and improve the spatial memory of mice.

Estimation of the benchmark dose of urinary cadmium as the reference level for renal dysfunction: a large sample study in five cadmium polluted areas in China

BACKGROUND

Itai-itai disease primarily results from cadmium (Cd) exposure and is known as one of the four major pollution diseases in Japan. Cd pollution is more serious in several areas of China than in Japan. However, there is still a lack of information regarding the threshold level of Cd exposure for the adverse health effects in the general Chinese population. This study aims to evaluate the reference value of urinary Cd (UCd) for renal dysfunction in a Chinese population as the benchmark dose lower confidence limit (BMDL) based on a large sample survey.

METHODS

A total of 6103 participants who lived in five Cd polluted areas of China participated in this study. We analyzed UCd levels as a biomarker of exposure and urinary β2-microglobulin (Uβ2-MG) levels as a renal tubular effect biomarker. The BMD studies were performed using BMD software. The benchmark response (BMR) was defined as a 10% additional risk above the background.

RESULTS

There was a positive correlation between the UCd levels and the prevalence of Uβ2-MG. The BMD of UCd for Uβ2-MG was estimated for each province. The findings showed that the BMD levels were related to the participants' geographic region, which may be partially due to the large differences in Cd exposure level, ethnic group, lifestyle and diet of the sample population in these study areas. The reference level of UCd for the renal effects was further evaluated by combining the five sets of data from all 6103 subjects. The overall BMDLs of UCd for Uβ2-MG with an excess risk of 10% were 2.00 μg/g creatinine (μg/g cr) in males and 1.69 μg/g cr in females, which were significantly lower than the World Health Organization (WHO) threshold level of 5 μg/g cr for Cd-related renal effects.

CONCLUSIONS

The selection of the sample population and geographic region affected the BMDL evaluation. Based on the findings of this survey of a large sample population, the UCd BMDLs for Uβ2-MG in males with BMRs at 10% were 2.00 μg/g cr. The BMD was slightly lower in females, which indicated that females may be relatively more sensitive to Cd exposure than males.

Cadmium contamination of rice from various polluted areas of China and its potential risks to human health

A total of 484 rice samples were collected from five polluted areas in China to investigate the cadmium (Cd) contamination of rice and its potential health risks. The mean Cd contents of analyzed rice samples obtained from different areas ranged from 0.149 to 0.189 mg·kg(-1). Cd concentrations in more than 18% of rice samples exceeded the maximum allowable Cd concentration, and the highest level of 41.1% was observed in samples from Hezhang, Guizhou, which was characterized by serious Cd pollution. Target hazard quotient (THQ) values of 1.5 to 7.8 from rice intake indicated a significant non-carcinogenic health risk for humans, particularly for highly exposed consumers. Children are more at risk than adults, as indicated by the higher THQs. Moreover, carcinogenic risks of Cd from rice intake for average and high consumers in the selected areas were two to three and four to eight greater, respectively, than the threshold value recommended by the International Commission on Radiological Protection.

Copper Tolerance and Biosorption of Saccharomyces cerevisiae during Alcoholic Fermentation

At high levels, copper in grape mash can inhibit yeast activity and cause stuck fermentations. Wine yeast has limited tolerance of copper and can reduce copper levels in wine during fermentation. This study aimed to understand copper tolerance of wine yeast and establish the mechanism by which yeast decreases copper in the must during fermentation. Three strains of Saccharomyces cerevisiae (lab selected strain BH8 and industrial strains AWRI R2 and Freddo) and a simple model fermentation system containing 0 to 1.50 mM Cu2+ were used. ICP-AES determined Cu ion concentration in the must decreasing differently by strains and initial copper levels during fermentation. Fermentation performance was heavily inhibited under copper stress, paralleled a decrease in viable cell numbers. Strain BH8 showed higher copper-tolerance than strain AWRI R2 and higher adsorption than Freddo. Yeast cell surface depression and intracellular structure deformation after copper treatment were observed by scanning electron microscopy and transmission electron microscopy; electronic differential system detected higher surface Cu and no intracellular Cu on 1.50 mM copper treated yeast cells. It is most probably that surface adsorption dominated the biosorption process of Cu2+ for strain BH8, with saturation being accomplished in 24 h. This study demonstrated that Saccharomyces cerevisiae strain BH8 has good tolerance and adsorption of Cu, and reduces Cu2+ concentrations during fermentation in simple model system mainly through surface adsorption. The results indicate that the strain selected from China's stress-tolerant wine grape is copper tolerant and can reduce copper in must when fermenting in a copper rich simple model system, and provided information for studies on mechanisms of heavy metal stress.

Correlating wine quality indicators to chemical and sensory measurements

Twenty-seven commercial Californian Cabernet Sauvignon wines of different quality categories were analyzed with sensory and chemical methods. Correlations between five quality proxies-points awarded during a wine competition, wine expert scores, retail price, vintage, and wine region-were correlated to sensory attributes, volatile compounds, and elemental composition. Wine quality is a multi-faceted construct, incorporating many different layers. Depending on the quality proxy studied, significant correlations between quality and attributes, volatiles and elements were found, some of them previously reported in the literature.