Pre-treatment and extraction techniques for recovery of added value compounds from wastes throughout the agri-food chain

The enormous quantity of food wastes discarded annually force to look for alternatives for this interesting feedstock. Thus, food bio-waste valorisation is one of the imperatives of the nowadays society. This review is the most comprehensive overview of currently existing technologies and processes in this field. It tackles classical and innovative physical, physico-chemical and chemical methods of food waste pre-treatment and extraction for recovery of added value compounds and detection by modern technologies and are an outcome of the COST Action EUBIS, TD1203 Food Waste Valorisation for Sustainable Chemicals, Materials and Fuels

Quality assessment of waters from South-East Serbia in respect to major dissolved elements

According to the density of water resources and the diversity of physico-chemical properties of mineral waters, the territory of Serbia belongs to the one of the most resourceful areas of the European continent. Due to poor data on the quality, only a small fraction of these waters is used as drinking and bottled water. Since safe and minerally- rich drinking water is one of the preconditions of good health and one of the basic health indicators of any country, the aim of this work was to evaluate the quality of spring, ground and some river waters from South- East Serbia region. The study area included the territory between the valley of the South Morava down river flow in the West, Balkan mountain range in the East, the mountains Bukovik and Rtanj in the north, and the mountains Vrdenik and Cemernik in the south. The technique of inductively coupled plasma-atomic emission spectrometry was used for mineral characterisation of natural waters from South-East Serbia. The analysis included determination of aluminium, arsenic, calcium, cadmium, cobalt, chromium, cooper, iron, potassium, magnesium, manganese, sodium, nickel, lead and zinc in spring, ground and river waters. Calculated contents were compared with Serbian regulations on the quality of water for human use, and directive of World Health Organization for maximum acceptable concentrations of chemical substances, Some spring and ground water samples contained high concentrations of macro-elements Ca, Mg and K. Those waters can be classified as mineral water in accordance with Serbian regulation for natural mineral water, spring water and bottled drinking water. Concentrations up to 84.2 ug/L, 8.10 pg/L and 14.9 ug/L of iron, manganese and copper, respectively, were recorded in some water samples and were within the permissible limits. Other heavy metals were not detected in analysed samples. Based on the derived results, it can be concluded that tested ground and spring water samples have a significant potential to be used as sources for the production of bottled water. Good quality of the river water samples qualifies these alluvial deposits as good sources of water supply to many communities close to this river. Although results are promising, further investigations are necessary. In the meantime, precautionary measures should be immediately taken to protect and preserve these water resources. The preservation of water resources should be performed in economically, socially, and environmentally sustainable manner

Chronopotentiometric stripping analysis of selenium using mercury film electrode

The influence of the most important experimental factors in chronopotentiometric stripping analysis (CSA) of selenium( IV) using mercury film working electrode was examined. Interferences of copper, iron and lead were investigated as well. The possibility of avoiding prolonged deaeration of the solution was examined by applying medium exchange modification of the technique, where the dissolution of the deposit was performed in calcium-chloride solution. Detection limits obtained for the modification of the CSA with prior deaeration and medium exchange modification were 0.4 μg/dmJ and 1.15μg/dmJ, respectively. Accuracy of the defined techniques has been confirmed by analysing reference material (RM 8436) -wheat durum flour. The results obtained by applying both modifications of the technique showed a very good agreement of total selenium content with declareted value

Determination of sensitivity limit in quantative analysis of polycyclic aromatic hydrocarbons by Gc-ms

The limit of detection (LOD) and the limit of quantitation (LOQ) for 16 individual PAHs from the Environmental Protection Agency (EPA) list (naphthalene, acenaphthylene, acenaphtene, fluorene, phenanthrene antrachene, fluoranthene, pyrene, benzo(a)anthracene, chrysene benzo(b)fluoranthene, benzo(k)fluoranthene, benzo(a)pyrene, dibenzo(a,h) anthracene, benzo(g,h,i)perylene and indeno(1,2,3-cd)pyrene) were determined by Gas Chromatography – Mass Spectrometry (GC-MS). Determination was performed by SCAN (digital linear scanning) and SIM (selected ion monitoring) techniques preceded by the optimization of the experimental factors. The limit of detection obtained by the SCAN technique was in the range of 0.179 – 15.236 ng, and the quantitation limit in the range of 1.017 – 50.788 ng. SIM technique enabled LOD and LOQ in the range of 0.036 – 13.886 pg and 0.119 – 46.287 pg respectively

Determination of As(III) and As(V) in waters by chronopotentiometric stripping analysis

Arsenic is a naturally occurring toxic and carcinogenic element. The degree of the toxicity depends on its chemical form and the concentration. Application of a sensitive, selective, simple and rapid method for detection and monitoring of different oxidation states of arsenic in waters is of great importance because main route of population exposure is through drinking water. In this work chronopotentiometric stripping analysis (CSA) was used for the determination of As(III) and As(V) in tap, well, river and rain waters from Vojvodina (Serbia). Gold film electrode on the glassy carbon support was used as the working electrode. The experimental parameters of the technique were investigated and optimized. Detection limit of the method for the electrolysis time of 600 s was 2 μg/dm3 of As(III)

Determination of the trans fatty acid content of Serbian shortenings by gas chromatography-mass spectrometry

The fatty acid composition and trans fatty acid (TFA) content of Serbian shortenings were determined by capillary gas chromatography-mass spectrometry. The saturated, cis-monounsaturated and polyunsaturated fatty acid contents were within the ranges of 16.0–89.0, 4.9–41.9 and 0.0–23.2% of total fatty acids, respectively. Among the saturated fatty acids, palmitic acid (4.8–48.7%) was dominant and its higher amount indicates that palm oil was the major contributor in the shortening manufacturing. The content of total trans fatty acids ranged from 0.0% to 48.7% of total fatty acids and the mean was 27.4%. Trans 18:1 isomers were the major group of TFA present in analysed samples, representing 94.2% of total trans isomers. The content of all 18:2 trans isomers ranged from 0.0% to 3.6% of total fatty acids. Among thirty-four analysed samples only six contained low level of TFA (0.0–3.1%) while the rest contained very high amounts of TFA (10.2–48.7%) which clearly indicate that partially hydrogenated vegetable oils are still the major raw materials used in the production of shortenings in Serbia

Determination of polycyclic aromatic hydrocarbons in soil by gas chromatography-mass spectrometry

Polycyclic aromatic hydrocarbons (PAHs) were determined in soil samples from forty different locations in Vojvodina. The samples were Soxhlet extracted cleaned-up and analyzed using gas chromatography-mass spectrometry (GC-MS) in the selected ion monitoring mode (SIM). Each PAH was separately quantified using an eight-point calibration of mixed standard solutions in the range between 0.25 and 10 μg/cm3. The sum of the 16 US Environmental Protection Agency PAHs analyzed in the soil samples varied from 0.043 to 1.362 mg/kg of dry soil

Bioactive compounds of sweet and sour cherry stems obtained by subcritical water extraction

© 2017 Society of Chemical Industry BACKGROUND: Sweet cherries (Prunus avium L.) and sour cherries (Prunus cerasus L.) contain substantial amounts of anthocyanins and polyphenolics, and their stems have been used in traditional medicine for centuries. However, comparative data on the composition of sweet and sour cherry stems using the same analytical methodologies are limited. Moreover, there is no data in terms of biological activity of subcritical water extracts of cherry stems. RESULTS AND DISSCUSION: Results obtained by using several assays that focused on different mechanisms showed that subcritical water extracts of sour and sweet cherry stems were powerful antiradicals and antioxidants. Anti-proliferative properties measured by MTT (3-[4,5- dimethylthiazol-2-yl]-2,5 diphenyl tetrazolium bromide) test showed prominent cytotoxicity against different tumor cell lines. Inhibitory concentrations obtained were in the range 8.38–11.40 µg mL-1. GC–MS (gas chromatography mass spectrometry) analysis showed the presence of alcohols, fatty acids, organic acids and other organic compounds. However, the chemical compositions of the two samples observed were similar, indicating similar chemical composition of sour and sweet cherry stems. CONCLUSION: Subcritical water extracts of cherry stem demonstrated excellent biological activity and the potential to be used for pharmaceuticals or supplements due to confirmed high antioxidant, antiradical and antitumor activity. © 2017 Society of Chemical Industry