Quality Assessment of Wild and Cultivated Green Tea from Different Regions of China.

Natural products have always enjoyed great popularity among consumers. Wild tea is an interesting alternative to tea from intensive plantations. The term "wild tea" is applied to many different varieties of tea, the most desirable and valued of which are native or indigenous tea plants. Special pro-health properties of wild tea are attributed to the natural conditions in which it grows. However, there are no complex studies that describe quality and health indicators of wild tea. The aim of this research was to evaluate the quality of wild and cultivated green tea from different regions of China: Wuzhishan, Baisha, Kunlushan, and Pu'Er. The assessment was carried out by verifying the concentration of selected chemical components in tea and relating it to the health risks they may pose, as well as to the nutritional requirements of adults. Wild tea was characterized by higher micronutrient concentration. The analyzed teas can constitute a valuable source of Mn in the diet. A higher concentration of nitrates and oxalates in cultivated tea can be associated with fertilizer use. The analyzed cultivated tea was a better source of antioxidants with a higher concentration of caffeine. There were no indications of health risks for wild or cultivated teas.

Building a quality index for soils impacted by proximity to an industrial complex using statistical and data-mining methods.

Differences in soil quality indices, in terms of the inherent properties of loess parent material and the potential for Zn, Pb and Cd contamination from the emissions of an adjacent large industrial complex, were determined. A set of independent variables was established for the soils, using principal component analysis (PCA) and a random forest (RF) method. The quality indices of 140 topsoil samples from the environs of an industrial complex were compared with those of reference soils taken from around the borders of the study area. Potential driving factors for the Zn, Pb and Cd concentrations were dehydrogenase activity (DHA), urease (Ure) activity and invertase activity (IA), C, N, K2O, MgO, P2O5 and soil clay content. Maps were generated to show the spatial distributions of the Zn, Pb and Cd contamination. Enrichment factors and potential ecological risks were calculated. We established that, in general, concentrations of Zn, Pb and Cd in the topsoil decreased with increasing distance from the industrial complex, and the levels of Zn and Cd exceeded established intervention values, even in some soils on arable land. The arable land was enriched in P2O5, while the highest values for K2O and MgO were found in wasteland soils. The mean C content of all the soils was about 2%, with N (about 0.2%), C/N ratio (about 12) and pH (about 6.9) in the order: arable land

Application of ash and municipal sewage sludge as macronutrient sources in sustainable plant biomass production.

Owing to the growing volumes of ash and sewage sludge waste, there is a requirement for theoretical and practical research into the use of these wastes as a source of nutrients. However, there are relatively few studies on the transfer of macronutrients in soil-plant systems amended with ash-sewage sludge mixtures under field conditions. The aim of the study was to determine the effect of bituminous coal ash (AC), biomass ash (AB), and municipal sewage sludge (MSS) on the quantity and quality of a grass-legume mixture. During a 6 year field experiment on a sandy loam soil treated with the wastes, applied as mixtures or separately, the plant yield; N, P, K, Na, Mg, and Ca uptake by plants; macronutrient content and ratios in the plant biomass; and the recovery rate of macronutrients by plants were evaluated. The AB-MSS treatment increased the yield in comparison to that where the wastes were applied separately. The N, P, and Ca contents in the plant biomass and N and P uptake under ash-sludge treatments were in the range observed for the ash and sewage sludge. The AB-MSS co-application resulted in the highest K uptake. The AC-MSS treatment increased K and Mg uptake in relation to AC treatment. When AC or AB was added to the MSS, the Ca uptake increased relative to the MSS treatment. The plant biomass under the AB treatment was optimal for biofuel purposes in terms of the chemical composition. The co-application of AC or AB with MSS resulted in the optimum Ca:Mg ratio for fodder purposes. The recovery rate of the macroelements decreased in the following order: K, N, P, Mg, Na, and Ca. The results support the co-application of solid wastes such as ash and municipal sewage sludge to improve productivity, support the recycling of macronutrients, improve sustainability through the reduction of ash and sewage sludge disposal, and reduce reliance on mineral fertilizer.

Polycyclic aromatic hydrocarbon and heavy metal contents in the urban soils in southern Poland.

In this study, we examined how urban and industrial sprawl has affected the concentrations of polycyclic aromatic hydrocarbons (PAHs) and heavy metals (HMs) in the soils of two towns with different levels of urbanisation and industrial development. The concentrations, sources and spatial distributions of PAHs and Zn, Pb and Cd in the soils of the central, residential and green areas of the second largest town in Poland (Krakow) were compared to similar parameters in analogous areas of Zakopane, a small tourist town. The concentration ranges of the PAHs were much higher in the Krakow (337-59,694 µg kg-1) than in the Zakopane (55-1180 µg kg-1) soils. The Krakow soils were also characterised by higher levels of Cd (2.33-4.18 mg kg-1) and Pb (24.2-82.1 mg kg-1) than the Zakopane soils, in which the Cd and Pb concentrations amounted to 0.57-2.29 and 17.8-67.8 mg kg-1, respectively. Positive matrix factorisation (PMF) analysis identified the emission sources of the soil PAHs in both studied towns. In the Krakow soils, the main sources of the PAHs were traffic emissions, petroleum combustion and the steel-industry, while in the Zakopane soils, they were coal and biomass combustion, used for heating houses, followed by vehicle and gasoline emissions. A human health risk assessment, based on the toxic equivalency factors of benzo(a)pyrene (BaPeq), indicated a low level of PAHs contamination in most of the studied areas. Only in one area in central Krakow the BaPeq concentration exceeded the permissible value by nine-fold.

Heavy metal contamination, microbiological spoilage and biogenic amine content in sushi available on the Polish market.

BACKGROUND: The present study determined the heavy metal contamination (mercury, cadmium, lead, arsenic and nickel) of nori, restaurant-served sushi and ready-to-eat sushi meals available via retail chains. Moreover, both microbiological load and biogenic amine content in ready-to-eat sushi meals were analysed. RESULTS: All of the nori samples contained high levels of Cd (2.122 mg kg-1 ), Ni (0.715 mg kg-1 ), As (34.56 mg kg-1 ) and Pb (0.659 mg kg-1 ). The studied sushi samples contained high levels of Ni and Pb, reaching 0.194 and 0.142 mg kg-1 wet weight, respectively, being potentially hazardous to women during pregnancy and lactation and small children. None of the studied samples contained high levels of Hg. Overall, 37% of ready-to-eat sushi meals exceeded a microbiological load of 106 cfu g-1 . However, biogenic amine content in all of the samples was low, with a highest histamine content of 2.05 mg kg-1 . CONCLUSION: Sushi is not the source of high levels of biogenic amines even with high microbiological loads. Nevertheless, the high microbiological loads at the end of the shelf-life indicate that some processors might have problems with the distribution chain or implement a poor hygienic regime. Moreover as a result of possible risk associated with heavy metal contamination, the present study highlights the need to establish new regulations regarding the contamination of nori and sushi. © 2017 Society of Chemical Industry.

Phytostabilization of Zn-Pb ore flotation tailings with Dianthus carthusianorum and Biscutella laevigata after amending with mineral fertilizers or sewage sludge.

Zinc-lead mining wastes remain largely unvegetated and prone to erosion for many years because of phytotoxic levels of residual heavy metals, low nutrient status and poor physical structure. The optimal solution for these areas is to restore plant cover using species which spontaneously appear on the spoils. These species are adapted to the conditions of tailings, and their establishment will promote further vegetation by increasing soil organic matter and development of a soil system capable of supporting the nutrient and water requirements of plants and microoorganisms. The potential of Dianthus carthusianorum and Biscutella laevigata to stabilize mine spoils was analysed in a three-year pot experiment. Post-flotation wastes accumulated after Zn and Pb recovery from ores, were collected from tailings and used as a substrate for plant growth. Seeds for seedling production were collected from plants growing spontaneously on mine tailings. Prior to the establishment of the three-year pot experiment, the substrate was amended with fertilizer NPK or municipal sewage sludge, supplemented with K2O (SS). Substrate samples were collected for chemical analyses, dehydrogenase and urease activities measurements each year at the end of the growing season. The plants were harvested three years after the amendments. Both tested plant species were equally suitable for revegetation of the tailings. The amendment including both SS and NPK resulted in an increase of Corg, Nt, available P, K, Mg contents, an increase of dehydrogenase (DHA) and urease activities and a decrease in the concentrations of the soluble forms of Zn, Pb and Cd. However, nutrient content, DHA activity and plant biomass were higher with SS than NPK addition. NPK application enhanced the substrate properties after the first growing season, while positive effects of SS use were still observed after three years. A longer-lasting positive effect of SS than NPK application was probably due to the high organic matter content in SS, which was gradually decomposing and releasing nutrients.

Microbiological and chemical safety concerns regarding frozen fillets obtained from Pangasius sutchi and Nile tilapia exported to European countries.

BACKGROUND: Microbiological and chemical safety concerns regarding frozen fillets from pangasius catfish (Pangasius hypophthalmus) exported to Poland, Germany and Ukraine and Nile tilapia (Oreochromis niloticus) exported to Poland and Germany were investigated by analyzing heavy metal residues, microbiological hazards, biogenic amines, and thiobarbituric acid (TBA) and total volatile basic nitrogen (TVB-N) content. RESULTS: The heavy metal residues from all studied samples were far lower than the limits established by authorities. The most abundant biogenic amine found was histamine, with a maximum content of 9.6 mg 100 g(-1) , found in pangasius exported to Poland. The total viable counts were from 2.8 log cfu g(-1) in pangasius exported to Ukraine to 4.3 log cfu g(-1) in pangasius exported to Germany. Vibrio spp. were present in 70-80% of all studied pangasius groups, whereas there no Vibrio spp. were found in the studied tilapia samples. 30% of Pangasius fillets exported to Poland were contaminated with coagulase-positive staphylococci. No E. coli was found in any of the studied samples. Although the results of TBA analysis differed significantly between studied groups, the malonic aldehyde content in all studied groups was still very low. The TVB-N content in frozen fillets from pangasius was significantly lower than in frozen tilapia fillets. CONCLUSIONS: We reported that pangasius catfish frozen fillets were widely contaminated with Vibrio spp., which could prove hazardous for the final consumer if the fish is eaten raw or undercooked. The rest of the analysis showed no other reason for concern associated with Nile tilapia and Pangasius catfish frozen fillet consumption.

Mathematical forecasting methods for predicting lead contents in animal organs on the basis of the environmental conditions.

The main objective of this study was to determine and describe the lead transfer in the soil-plant-animal system in areas polluted with this metal at varying degrees, with the use of mathematical forecasting methods and data mining tools contained in the Statistica 9.0 software programme. The starting point for the forecasting models comprised results derived from an analysis of different features of soil and plants, collected from 139 locations in an area covering 100km(2) around a lead-zinc ore mining and processing plant ('Boleslaw'), at Bukowno in southern Poland. In addition, the lead content was determined in the tissues and organs of 110 small rodents (mainly mice) caught in the same area. The prediction models, elaborated with the use of classification algorithms, forecasted with high probability the class (range) of pollution in animal tissues and organs with lead, based on various soil and plant properties of the study area. However, prediction models which use multilayer neural networks made it possible to calculate the content of lead (predicted versus measured) in animal tissues and organs with an excellent correlation coefficient.

Quality of gluten-free supplemented cakes and biscuits.

Gluten-free confectionery products were used as controls for comparison with the products, which included different supplements such as linseed meal, amaranth and/or buckwheat. The latter were expected to increase nutritional values of confectionery products. Cookies were analyzed in terms of volume, selected textural parameters (hardness, cohesiveness), organoleptic quality, shelf-life, and different chemical components. All supplemented gluten-free products received high consumer scores, exceeding in some cases those of control samples. Supplementation of gluten-free confectionery products with linseed meal, amaranth and/or buckwheat flours enhanced their final nutritional quality. A significant rise was observed in the protein content and dietary fiber, and in the case of linseed meal also alpha-linolenic acid. All of the supplemented gluten-free confectionery products contained more macro-elements and micro-elements (i.e. potassium, phosphorus, magnesium, calcium, iron, manganese, zinc and copper), as compared with the controls. Taking into account the amino-acid composition, amaranth proved a more beneficial supplement of gluten-free products than linseed.