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As the world's population increases, so does the amount of wastewater generated during agricultural activities. Inadequate wastewater management can be the cause of sea and river pollution. However, wastewater can be a potential source of biologically active components that can be obtained via physicochemical, biological, thermochemical or combined treatments. Olive mill wastewater is produced in huge quantities around the world during the production of olive oil. This waste is harmful to the ecological system due to the high content of phenolic components that can be recovered by different methods whereby this waste also gains economic value. This review describes several methods that can be used in phenol removal or isolation from olive mill wastewater. [ABSTRACT FROM AUTHOR]

Cinnamon, a commonly used spice as well as a part of many commodities, such as breakfast cereals, teas and bakery products, represents an important part of the diet. Cinnamon, among many bioactive components, contains an important active compound coumarin. Numerous studies have shown that coumarin has a beneficial health effect on the body in optimal consumption, while increased long-term consumption can lead to adverse health effects. In this paper, the amount of coumarin in ten different products found on the Croatian market, including ground spices and teas, was analyzed. In addition, different extraction parameters were analyzed in order to find the best method [ABSTRACT FROM AUTHOR]

The aim of this study was to demonstrate that certain types of extraction techniques can give extracts with various bioactive components in different concentrations. Four green extraction techniques were used in this study: supercritical CO2 extraction, ultrasound-assisted extraction, cold atmospheric plasma extraction and extraction using deep eutectic solvents. Those modern techniques gave better yields of bioactive components and showed better antioxidant activity of obtained extracts than classical Soxhlet extraction. The bioactive components in obtained extracts were quantified by High Performance Liquid Chromatography. Supercritical CO2 extraction gave the highest yields for theobromine content, while ultrasound-assisted extraction with 50% aqueous ethanol solution gave the highest caffeine yields during 30 min of extraction, 35 Hz and 60 °C. The extraction with deep eutectic solvent mixture of choline chloride: oxalic acid and 50% pure H2O at room temperature during 180 min of extraction time gave the highest total phenol content while the same mixture under the same conditions, but during longer extraction time (360 min), gave the highest antioxidant activity. Cocoa shell (CS), due to its nutritional value and bioactive components, has a potential to become a desirable raw material in a large spectrum of functional and pharmaceutical products. [ABSTRACT FROM AUTHOR]

Inhibitory effect of 32 coumarin derivatives (20 Schiff bases, 5 thiosemicarbazides, 5 thiazolidinones, and their precursors, 7-hydroxy-4-methylcoumarin and 4-methylcoumarin-7-yl hydrazine carboxylate) on partially purified apple polyphenol oxidase was investigated. Thirteen coumarin derivatives inhibited polyphenol oxidase (5 Schiff bases, 5 thiosemicarbazides, 1 thiazolidinone, 4-methyl-7-hydroxycoumarin and 4-methylcoumarin-7-yl hydrazine carboxylate), while 19 derivatives showed no effect on enzyme activity. The most effective inhibitors were thiosemicarbazides, with 4-methyl-1-(2-(4-methyl-2- oxo-2H-chromen-7-yloxy)acetyl) thiosemicarbazide (compound C23) being the most prominent inhibitor (IC50 = 10.45 μM). The importance of thiosemicarbazide moiety as crucial structure element for strong apple PPO inhibition was confirmed by its cyclisation to thiazolidinone bearing the same substituents as corresponding thiosemicarbazide. Capture of the sulphur atom of thiosemicarbazide group within tiazolidinone ring caused significant loss of inhibitory effect against apple PPO. [ABSTRACT FROM AUTHOR]