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Antibiotics are a group of drugs used for the treatment of bacterial diseases. They are used in both human and veterinary medicine and, although they are not permitted, they are sometimes used as growth promoters. The present research compares two extraction techniques: ultrasound-assisted extraction (UAE) and microwave-assisted extraction (MAE) in order to evaluate their efficiency in the determination of 17 usually prescribed antibiotics in human nails. The extraction parameters were optimized using multivariate techniques. Once both techniques were compared, MAE was selected as optimal due to its greater experimental practicability together with the better extraction efficiencies it provides. Target analytes were detected and quantified by ultra-high performance liquid chromatography with tandem mass spectrometry detection (UHPLC-MS/MS). The run time was 20 min. The methodology was then successfully validated, obtaining acceptable analytical parameters according to the guide used. Limits of detection were between 0.3 and 3 ng g−1 and limits of quantification were in the range from 1.0 to 4.0 ng g−1. Recovery percentages ranged from 87.5% to 114.2%, and precision (in terms of standard deviation) was less than 15% in all cases. Finally, the optimized method was applied to nails taken from 10 volunteers and the results revealed the presence of one or more antibiotics in all the samples examined. The most commonly found antibiotic was sulfamethoxazole, followed by danofloxacin and levofloxacin. The results demonstrated, on the one hand, the presence of these compounds in the human body and, on the other hand, the suitability of nails as a non-invasive biomarker of exposure.

The production of pistachio in Tunisia generates a large amount of potentially valuable waste, such as leaves, that could be used as source of bioactive compounds. In this work, the extraction of phytochemicals from Pistacia vera L. leaves (male and female) by microwave-assisted extraction (MAE) has been investigated. A response surface methodology (RSM) was used for the optimization of bioactive compounds extraction, where the independent variables were temperature and extraction time, and the dependent variable was extraction yield. Total phenolic content (TPC), total flavonoid content (TFC), antioxidant activities (DPPH, ABTS, and FRAP) and antimicrobial activity of the extracts obtained at optimal conditions for both leaves were evaluated and compared not only between them, but also with the extracts obtained by maceration. The optimum extraction conditions were 70 ? and 61 ?, and 5.6 and 12 min for male and female leaves respectivily. The best results were achieved for female leaves by MAE with 36% of extraction yield, TPC of 196.35 mg gallic acid equivalents (GAE)/g dry weight (DW), TFC of 83.34 mg catechin equivalents (CE)/g dry weight (DW), and high antioxidant and antimicrobial activities. The evaluation of biological activity of the extracts showed that MAE provides extracts with better antioxidant and antimicrobial capacities then those obtained by maceration. More-over, UPLC-DAD-ESI-MS was performed to confirm the presence of some phenolic compounds in MAE extracts, such as quercetin, apigenin and myricetin derivatives. The results revealed that MAE is an efficient technique for the extraction of active components from Pistacia vera L. leaves.

Olea europaea L. leaves constitute a source of bioactive compounds with recognized benefits for both human health and technological purposes. In the present work, different extracts from olive leaves were obtained by the application of two extraction methods, Soxhlet and microwave-assisted extraction (MAE), and six solvents (distilled water, ethanolic and glycerol mixtures solvents). MAE was applied under 40, 60 and 80 °C for 3, 6.5 and 10 min. The effect of the extraction method, solvent and treatment factors (the latter in MAE) on the total phenol content (TPC), the antioxidant activity (AA) and the phenolic profile of the extracts were all evaluated. The extracts showed high values of TPC (up to 76.1 mg GAE/g DW) and AA (up to 78 mg TE/g DW), with oleuropein being the most predominant compound in all extracts. The Soxhlet extraction method exhibited better yields in TPC than in MAE, although both methods presented comparable AA values. The water MAE extract presented the strongest antimicrobial activity against five foodborne pathogens, with minimum inhibitory concentration (MIC) values ranging from 2.5 to 60 mg/mL. MAE water extract is proposed to be exploited in the food and nutraceutical industry in the frame of a sustainable economy.

U okviru ove disertacije ispitane su mogućnosti primene savremenih metoda za dobijanje tečnih ekstrakata (ultrazvučna ekstrakcija, mikrotalasna ekstrakcija i ekstrakcija subkritičnom vodom) i lipofilnih ekstrakata (ekstrakcija superkritičnim ugljendioksidom) bogatih polifenolima iz nadzemnog dela očajnice (Marrubium vulgare L.). Tečni ekstrakti su optimizovani primenom eksperimentalnog dizajna i metode odzivne površine, i podvrgnuti su spray drying tehnici sušenja. Tečni i suvi ekstrakti su detaljno ispitani po pitanju hemijskog sastava i biološke aktivnosti, antimikrobne i in vitro antihiperglikemijske aktivnosti. Za svaku od navedenih ekstrakcionih tehnika ispitan je uticaj glavnih parametara: ultrazvučna ekstrakcija (temperatura, vreme ekstrakcije i snaga ultrazvuka), mikrotalasna ekstrakcija (koncentracija etanola, vreme ekstrakcije i snaga mikrotalasa) i ekstrakcija subkritičnom vodom (temperatura, vreme ekstrakcije i koncentracija HCl u ekstragensu). Kod tečnih ekstrakata dobijenih ultrazvučnom i mikrotalasnom ekstrakcijom na optimizovanim uslovima utvrđeno je prisustvo hlorogenske kiseline i kvercetina koji nisu detektovani u maceratima. Ispitana je antimikrobna aktivnost oba ekstrakta i utvrđeno da je B. cereus najosetljiviji bakterijski soj, dok je u slučaju kvasaca S. cerevisiae posebno osetljiv na oba ekstrakta. Pored ove aktivnosti ispitana je i in vitro antihiperglikemijska aktivnost oba ekstrakta prema α-amilazi i α-glukozidazi, pri čemu ultrazvučni ekstrakt pokazuje veću antihiperglikemijsku aktivnost (50,63% inhibira α-amilazu i 48,67% inhibira α-glukozidazu) što se potencijalno može objasniti prisustvom hlorogenske kiseline (33,11 μg/mL) i kvercetina (34,88 μg/mL). U subkritičnom ekstraktu, dobijenom na optimalnim uslovima, detektovano je jedino prisustvo hidroksi metilfurfurala usled čega ovaj ekstrakt nije podvrgnut ispitivanju antimikrobne i antihiperglikemijske aktivnosti. U cilju ekstrakcije lipofilnih komponenata M. vulgare primenjene su desti, Within the scope of this dissertation, the possibilities of applying modern methods for obtaining liquid (ultrasonic extraction, microwave extraction and subcritical water extraction) and lipophilic extracts (extraction with supercritical carbon dioxide) rich in polyphenols from the aboveground part of white horehound (Marrubium vulgare L.) were examined. Liquid extracts were optimized using an experimental design and response surface method, and subjected to spray drying. Liquid and dry extracts have been extensively examined for their chemical composition and biological activity, antimicrobial and in vitro antihyperglycaemic activities. For each of these extraction techniques, the influence of the main parameters was examined: ultrasonic extraction (temperature, extraction time and ultrasound power), microwave extraction (ethanol concentration, extraction time and microwave power) and subcritical water extraction (temperature, extraction time and HCl concentration in the extractant). Liquid extracts obtained by ultrasonic and microwave extraction under optimized conditions revealed the presence of chlorogenic acid and quercetin, which were not detected in macerates. The antimicrobial activity of both extracts was examined and B. cereus was found to be the most sensitive bacterial strain, whereas in the case of yeast S. cerevisiae was particularly sensitive to both extracts. In addition to this activity, the in vitro antihyperglycaemic activities of both extracts against α-amylase and α-glucosidase were investigated, with ultrasound extract showing higher antihyperglycemic activity (50.63% inhibited α-amylase and 48.67% inhibited α-glucosidase) which could potentially be explained by the presence of chlorogenic acid (33.11 μg/mL) and quercetin (34.88 μg/mL). In the subcritical extract, obtained under optimal conditions, only the presence of hydroxy methylfurfural was detected, and this extract was not subjected to antimicrobial and antihyperglycemic activity. For t

In this study, the recovery of polyphenols from olive oil mill and winery waste was investigated. The performance of ultrasound assisted extraction (UAE), microwave assisted extraction (MAE), and pressurized liquid extraction (PLE) was assessed using ethanol–water mixtures, which are compatible with food, nutraceutical, and cosmetic applications. The extraction efficiency from olive pomace and lees samples was evaluated in terms of total polyphenol content (TPC), determined by high performance liquid chromatography (HPLC) and Folin–Ciocalteu assay. The effect of solvent composition, temperature, and time was analyzed by response surface methodology. Ethanol:water 50:50 (v/v) was found to be a suitable solvent mixture for both kinds of samples and all three extraction techniques. The performance of the extraction techniques was evaluated, under optimal experimental conditions, with a set of different representative samples of residues from olive oil and wine production. Overall, the best extraction efficiency for olive pomace residues was provided by MAE (ethanol:water 50:50 (v/v), 90 °C, 5 min), and for wine residues by PLE (ethanol:water 50:50 (v/v), 100 °C, 5 min, 1 cycle). However, the results provided by UAE (ethanol:water 50:50 (v/v), 30 min) were also suitable. Considering not only extraction performance, but also investment and operational costs, UAE is proposed for a future scaling up evaluation. Regarding olive pomace as a source for natural phenolic antioxidants, olive variety and climatic conditions should be taken into account, since both influence TPC in the extracts, while for winery residues, lees from red wines are more suitable than those from white wines., Peer Reviewed, Postprint (published version)

In this study, the recovery of polyphenols from olive oil mill and winery waste was investigated. The performance of ultrasound assisted extraction (UAE), microwave assisted extraction (MAE), and pressurized liquid extraction (PLE) was assessed using ethanol–water mixtures, which are compatible with food, nutraceutical, and cosmetic applications. The extraction efficiency from olive pomace and lees samples was evaluated in terms of total polyphenol content (TPC), determined by high performance liquid chromatography (HPLC) and Folin–Ciocalteu assay. The effect of solvent composition, temperature, and time was analyzed by response surface methodology. Ethanol:water 50:50 (v/v) was found to be a suitable solvent mixture for both kinds of samples and all three extraction techniques. The performance of the extraction techniques was evaluated, under optimal experimental conditions, with a set of different representative samples of residues from olive oil and wine production. Overall, the best extraction efficiency for olive pomace residues was provided by MAE (ethanol:water 50:50 (v/v), 90 °C, 5 min), and for wine residues by PLE (ethanol:water 50:50 (v/v), 100 °C, 5 min, 1 cycle). However, the results provided by UAE (ethanol:water 50:50 (v/v), 30 min) were also suitable. Considering not only extraction performance, but also investment and operational costs, UAE is proposed for a future scaling up evaluation. Regarding olive pomace as a source for natural phenolic antioxidants, olive variety and climatic conditions should be taken into account, since both influence TPC in the extracts, while for winery residues, lees from red wines are more suitable than those from white wines., Peer Reviewed, Postprint (published version)

Ethnopharmacological relevance: Thapsia garganica L. roots are used in Algerian traditional medicine for a number of ailments. It is used in a poultice as an antitussive treatment of acute bronchitis and pneumonia, in preparations with milk or oil taken orally to treat common lung diseases, and with the direct application of root sections for the soothing of dental pains. Aim of the study: The objective of this study was to evaluate the combined effect of microwave assisted extraction and gamma irradiation on sesquiterpene lactones in T. garganica extracts Materials and methods: To evaluate the combined effect of microwave assisted extraction and gamma irradiation on the highly bioactive compounds found in extracts of Algerian T. garganica, samples from different locations in Algeria were prepared by extraction from dried leaf and root samples of dried plant material, using different extraction methods Quantification of the compounds of interest was done using an HPLC. The antioxidant activity extracts was determined using the two free radical scavenging assays: the 2,2-diphenyl-picryl-hydrazyl (DPPH) and the 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) diammonium salt (ABTS). Results: It was found that location and extraction method had significant impact on the phytochemical composition of extracts. Gamma irradiation was found to have no effect on the phytochemical composition of the plant extracts or on their antioxidant properties. Conclusion: The study has shown that microwave assisted extraction is an effective method for investigating chemical compounds in T. garganica and the results support the notion that gamma irradiation for sterilisation do not alter the chemical composition. The authors wish to clarify that we cannot recommend the usage of any parts of T. garganica, in any form, for any remedy due to its very high toxicity.

A new microwave-assisted extraction (MAE) method using ethanol as solvent has been optimized by means of a Box-Behnken experimental design for the enhanced extraction of bioactive terpenoids from Mentha rotundifolia leaves; 100°C, 5 min, 1.125 g dry sample: 10 mL solvent and a single extraction cycle were selected as optimal conditions. Improved performance of MAE method in terms of extraction yield and/or reproducibility over conventional solid-liquid extraction and ultrasound assisted extraction was also previously assessed. A comprehensive characterization of MAE extracts was carried out by GC-MS. A total of 46 compounds, mostly terpenoids, were identified; piperitenone oxide and piperitenone were the major compounds determined. Several neophytadiene isomers were also detected for the first time in MAE extracts. Different procedures (solid-phase extraction and activated charcoal (AC) treatment) were also evaluated for clean-up of MAE extracts, with AC providing the highest enrichment in bioactive terpenoids. Finally, the MAE method here developed is shown as a green, fast, efficient and reproducible liquid extraction methodology to obtain M. rotundifolia bioactive extracts for further application, among others, as food preservatives.

Ethnopharmacological relevance: Thapsia garganica L. roots are used in Algerian traditional medicine for a number of ailments. It is used in a poultice as an antitussive treatment of acute bronchitis and pneumonia, in preparations with milk or oil taken orally to treat common lung diseases, and with the direct application of root sections for the soothing of dental pains. Aim of the study: The objective of this study was to evaluate the combined effect of microwave assisted extraction and gamma irradiation on sesquiterpene lactones in T. garganica extracts. Materials and methods: To evaluate the combined effect of microwave assisted extraction and gamma irradiation on the highly bioactive compounds found in extracts of Algerian T. garganica, samples from different locations in Algeria were prepared by extraction from dried leaf and root samples of dried plant material, using different extraction methods Quantification of the compounds of interest was done using an HPLC. The antioxidant activity extracts was determined using the two free radical scavenging assays: the 2,2-diphenyl-picryl-hydrazyl (DPPH) and the 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) diammonium salt (ABTS). Results: It was found that location and extraction method had significant impact on the phytochemical composition of extracts. Gamma irradiation was found to have no effect on the phytochemical composition of the plant extracts or on their antioxidant properties. Conclusion: The study has shown that microwave assisted extraction is an effective method for investigating chemical compounds in T. garganica and the results support the notion that gamma irradiation for sterilisation do not alter the chemical composition.The authors wish to clarify that we cannot recommend the usage of any parts of T. garganica, in any form, for any remedy due to its very high toxicity.

Sagorevanje uglja, zajedno sa njegovom eksplatacijom, odlaganjem pepela i drugim pratećim procesima, predstavlja glavni izvor potencijalno toksičnih elemenata koji zagađuju čovekovu okolinu, kao što su: As, Be, Cd, Cr, Hg, Pb, Sb, Th, U i drugi. Istraživanja i praćenje negativnih uticaja mikroelemenata na životnu sredinu imaju izuzetan značaj. Naročito je značajno identifikovanje i praktična primena novih pristupa, metoda, tehnika i uređaja u proceni uticaja zagađivačkih elemenata na životnu sredinu. Ispitivanja imaju za krajnji zadatak da se pronađu ekonomičnije i efikasnije alternative za skladištenje pepela na deponijama i izračunavanja potencijalnog zagađenja iz uglja i pepela. U ovom radu ispitana je mobilnost i dostupnost metala i neorganskih anjona iz uglja i elektrofilterskog pepela. Uzorci uglja su uzorkovani iz Kostolačkog basena, a pepeo je proizvod sagorevanja uglja Kostalačke termoelektrane. U cilju simulitanja ponašanja elemenata u uslovima životne sredine i ispitivanja ispiranja elemenata u životnu sredinu uzorci su ekstrahovani destilovanom vodom. Korišćene su različite tehnike ekstrahovanja: rotaciono mućkanje, ultrazvučna i mikrotalasnu ekstrakcija. Inetrakcije matriksa sa vodom ispitane su promenom ekstrakcionih vremena i temperature mikrotalasne ekstrakcije. Određivane su koncentracije elemenata: Al, As, Be, Ca, Cd, Co, Cr, Fe, Hg, K, Mg, Mn, Na, Ni, Pb, Sb i Se metodom indukovano sregnute plazme sa optičkom emisionom spektrometrijom (ICP-OES). Konstituenski elementi: K, Na, Ca i Mg paralelno su određeni jonskom hromatografijom (IC). Takođe, i dostupni konstituentni i zagađivački neorganski anjoni su određeni jonskom hromatografijom. Tačnost i pouzdanost rezultata proverena je merenjem koncentracije fluorida jon selektivnom elektrodom, kao i korišćenjem sertifikovanog referentnog materijala. Budući da se mikrotalasna ekstrakcija pokazala bržom i efikasnijom od druge dve tehnike, u daljem radu je uticaj mikrotalasa primenjen za sprovođenje sekvenc, Coal combustion along with its exploitation, ash disposal and other related processes constitutes the main source of potentially toxic elements that cause environmental pollution, such as As, Be, Cd, Cr, Hg, Pb, Sb, Th, U and others. It is very important that negative effects of microelements on the environment be thoroughly researched. They also require systematic and continuous monitoring. Another major task is to identify and adopt in practice new approaches to environmental impact assessments for pollutant elements. New methods, techniques and devices need also to be developed and applied. The end goal of this investigation was to find more cost-efficient and effective alternatives for ash storage at landfills and methods for calculating the level of potential pollution caused by coal and ash. The investigation involved tests for mobility and availability of metals and inorganic anions from coal and fly ash. Coal samples were collected from the Kostolac mine, while ash samples were the products of combustion of coal from the Kostolac thermal power plant. In order to simulate the actual behavior of elements and the process of their leaching into the environment, the samples were extracted using deionized water. Various extraction techniques were used, such as a rotary shaker, ultrasonic and microwave assisted extraction. Matrix interactions with water were investigated by varying the times and temperatures of microwave assisted extraction. Inductively coupled plasma optic emission spectrometry (ICP-OES) was used to measure the concentrations of the following elements: Al, As, Be, Ca, Cd, Co, Cr, Fe, Hg, K, Mg, Mn, Na, Ni, Pb, Sb and Se. The constituent elements, namely K, Na, Ca and Mg were identified in parallel by employing ion chromatography. The accuracy and reliability of obtained results was verified by measuring the concentration of fluorides using an ionselective electrode as well as certified reference material. Since the microwave assisted extraction ha

Sagorevanje uglja, zajedno sa njegovom eksplatacijom, odlaganjem pepela i drugim pratećim procesima, predstavlja glavni izvor potencijalno toksičnih elemenata koji zagađuju čovekovu okolinu, kao što su: As, Be, Cd, Cr, Hg, Pb, Sb, Th, U i drugi. Istraživanja i praćenje negativnih uticaja mikroelemenata na životnu sredinu imaju izuzetan značaj. Naročito je značajno identifikovanje i praktična primena novih pristupa, metoda, tehnika i uređaja u proceni uticaja zagađivačkih elemenata na životnu sredinu. Ispitivanja imaju za krajnji zadatak da se pronađu ekonomičnije i efikasnije alternative za skladištenje pepela na deponijama i izračunavanja potencijalnog zagađenja iz uglja i pepela. U ovom radu ispitana je mobilnost i dostupnost metala i neorganskih anjona iz uglja i elektrofilterskog pepela. Uzorci uglja su uzorkovani iz Kostolačkog basena, a pepeo je proizvod sagorevanja uglja Kostalačke termoelektrane. U cilju simulitanja ponašanja elemenata u uslovima životne sredine i ispitivanja ispiranja elemenata u životnu sredinu uzorci su ekstrahovani destilovanom vodom. Korišćene su različite tehnike ekstrahovanja: rotaciono mućkanje, ultrazvučna i mikrotalasnu ekstrakcija. Inetrakcije matriksa sa vodom ispitane su promenom ekstrakcionih vremena i temperature mikrotalasne ekstrakcije. Određivane su koncentracije elemenata: Al, As, Be, Ca, Cd, Co, Cr, Fe, Hg, K, Mg, Mn, Na, Ni, Pb, Sb i Se metodom indukovano sregnute plazme sa optičkom emisionom spektrometrijom (ICP-OES). Konstituenski elementi: K, Na, Ca i Mg paralelno su određeni jonskom hromatografijom (IC). Takođe, i dostupni konstituentni i zagađivački neorganski anjoni su određeni jonskom hromatografijom. Tačnost i pouzdanost rezultata proverena je merenjem koncentracije fluorida jon selektivnom elektrodom, kao i korišćenjem sertifikovanog referentnog materijala. Budući da se mikrotalasna ekstrakcija pokazala bržom i efikasnijom od druge dve tehnike, u daljem radu je uticaj mikrotalasa primenjen za sprovođenje sekvenc, Coal combustion along with its exploitation, ash disposal and other related processes constitutes the main source of potentially toxic elements that cause environmental pollution, such as As, Be, Cd, Cr, Hg, Pb, Sb, Th, U and others. It is very important that negative effects of microelements on the environment be thoroughly researched. They also require systematic and continuous monitoring. Another major task is to identify and adopt in practice new approaches to environmental impact assessments for pollutant elements. New methods, techniques and devices need also to be developed and applied. The end goal of this investigation was to find more cost-efficient and effective alternatives for ash storage at landfills and methods for calculating the level of potential pollution caused by coal and ash. The investigation involved tests for mobility and availability of metals and inorganic anions from coal and fly ash. Coal samples were collected from the Kostolac mine, while ash samples were the products of combustion of coal from the Kostolac thermal power plant. In order to simulate the actual behavior of elements and the process of their leaching into the environment, the samples were extracted using deionized water. Various extraction techniques were used, such as a rotary shaker, ultrasonic and microwave assisted extraction. Matrix interactions with water were investigated by varying the times and temperatures of microwave assisted extraction. Inductively coupled plasma optic emission spectrometry (ICP-OES) was used to measure the concentrations of the following elements: Al, As, Be, Ca, Cd, Co, Cr, Fe, Hg, K, Mg, Mn, Na, Ni, Pb, Sb and Se. The constituent elements, namely K, Na, Ca and Mg were identified in parallel by employing ion chromatography. The accuracy and reliability of obtained results was verified by measuring the concentration of fluorides using an ionselective electrode as well as certified reference material...

A huge amount of espresso spent coffee grounds (SCG) are obtained as a waste product during the preparation of coffee beverages (cialdes, K-cups and in metallic filters). Although considered a waste and an ecological threat, SCGs could be an excellent source of bioactive components (mainly polyphenols) with outstanding antioxidative activity and potential to be used as raw material in fortified food production. The antiplatelet action of dietary polyphenols represents an important part of their pleiotropic action, and underlying mechanisms of their shown beneficial effects on cardiovascular health. Accordingly, a reduction in platelet aggregation was accepted by EFSA as a beneficial effect of food and dietary constituents, in the context of maintaining cardiovascular health enabling claims related to foods or substances affecting disturbed platelet function. Thus, platelets are considered an emerging target for the prophylactic effects of food bioactives in cardiovascular disease (CVD), with promising scientific evidence of their efficacy. The overall objective of this study was to examine an optimal range of extraction conditions for the extraction of polyphenols from espresso SCGs by using response surface methodology and to investigate the in vitro effects of obtained polyphenol-rich extracts on platelet activation and their aggregation with monocytes and neutrophiles. The obtained results indicated that espresso SCG extracts induce dose dependent inhibition of platelet activation, shown by the decrease in expression of P-selectin (8.7%) and GPIIb/IIIa (5.6%) and their aggregation with monocytes and neutrophiles (up to 20%). The sustainability of the coffee processing system can be substantially improved through the use of by-products by the adoption of new technologies that maximize process profitability. Shown antiplatelet effects of polyphenols, present in espresso coffee SCGs, indicate a favorable profile of bioactive compounds toward platelet function and th

A huge amount of espresso spent coffee grounds (SCG) are obtained as a waste product during the preparation of coffee beverages (cialdes, K-cups and in metallic filters). Although considered a waste and an ecological threat, SCGs could be an excellent source of bioactive components (mainly polyphenols) with outstanding antioxidative activity and potential to be used as raw material in fortified food production. The antiplatelet action of dietary polyphenols represents an important part of their pleiotropic action, and underlying mechanisms of their shown beneficial effects on cardiovascular health. Accordingly, a reduction in platelet aggregation was accepted by EFSA as a beneficial effect of food and dietary constituents, in the context of maintaining cardiovascular health enabling claims related to foods or substances affecting disturbed platelet function. Thus, platelets are considered an emerging target for the prophylactic effects of food bioactives in cardiovascular disease (CVD), with promising scientific evidence of their efficacy. The overall objective of this study was to examine an optimal range of extraction conditions for the extraction of polyphenols from espresso SCGs by using response surface methodology and to investigate the in vitro effects of obtained polyphenol-rich extracts on platelet activation and their aggregation with monocytes and neutrophiles. The obtained results indicated that espresso SCG extracts induce dose dependent inhibition of platelet activation, shown by the decrease in expression of P-selectin (8.7%) and GPIIb/IIIa (5.6%) and their aggregation with monocytes and neutrophiles (up to 20%). The sustainability of the coffee processing system can be substantially improved through the use of by-products by the adoption of new technologies that maximize process profitability. Shown antiplatelet effects of polyphenols, present in espresso coffee SCGs, indicate a favorable profile of bioactive compounds toward platelet function and th

A huge amount of espresso spent coffee grounds (SCG) are obtained as a waste product during the preparation of coffee beverages (cialdes, K-cups and in metallic filters). Although considered a waste and an ecological threat, SCGs could be an excellent source of bioactive components (mainly polyphenols) with outstanding antioxidative activity and potential to be used as raw material in fortified food production. The antiplatelet action of dietary polyphenols represents an important part of their pleiotropic action, and underlying mechanisms of their shown beneficial effects on cardiovascular health. Accordingly, a reduction in platelet aggregation was accepted by EFSA as a beneficial effect of food and dietary constituents, in the context of maintaining cardiovascular health enabling claims related to foods or substances affecting disturbed platelet function. Thus, platelets are considered an emerging target for the prophylactic effects of food bioactives in cardiovascular disease (CVD), with promising scientific evidence of their efficacy. The overall objective of this study was to examine an optimal range of extraction conditions for the extraction of polyphenols from espresso SCGs by using response surface methodology and to investigate the in vitro effects of obtained polyphenol-rich extracts on platelet activation and their aggregation with monocytes and neutrophiles. The obtained results indicated that espresso SCG extracts induce dose dependent inhibition of platelet activation, shown by the decrease in expression of P-selectin (8.7%) and GPIIb/IIIa (5.6%) and their aggregation with monocytes and neutrophiles (up to 20%). The sustainability of the coffee processing system can be substantially improved through the use of by-products by the adoption of new technologies that maximize process profitability. Shown antiplatelet effects of polyphenols, present in espresso coffee SCGs, indicate a favorable profile of bioactive compounds toward platelet function and th

A huge amount of espresso spent coffee grounds (SCG) are obtained as a waste product during the preparation of coffee beverages (cialdes, K-cups and in metallic filters). Although considered a waste and an ecological threat, SCGs could be an excellent source of bioactive components (mainly polyphenols) with outstanding antioxidative activity and potential to be used as raw material in fortified food production. The antiplatelet action of dietary polyphenols represents an important part of their pleiotropic action, and underlying mechanisms of their shown beneficial effects on cardiovascular health. Accordingly, a reduction in platelet aggregation was accepted by EFSA as a beneficial effect of food and dietary constituents, in the context of maintaining cardiovascular health enabling claims related to foods or substances affecting disturbed platelet function. Thus, platelets are considered an emerging target for the prophylactic effects of food bioactives in cardiovascular disease (CVD), with promising scientific evidence of their efficacy. The overall objective of this study was to examine an optimal range of extraction conditions for the extraction of polyphenols from espresso SCGs by using response surface methodology and to investigate the in vitro effects of obtained polyphenol-rich extracts on platelet activation and their aggregation with monocytes and neutrophiles. The obtained results indicated that espresso SCG extracts induce dose dependent inhibition of platelet activation, shown by the decrease in expression of P-selectin (8.7%) and GPIIb/IIIa (5.6%) and their aggregation with monocytes and neutrophiles (up to 20%). The sustainability of the coffee processing system can be substantially improved through the use of by-products by the adoption of new technologies that maximize process profitability. Shown antiplatelet effects of polyphenols, present in espresso coffee SCGs, indicate a favorable profile of bioactive compounds toward platelet function and th

Extracts of the Pongamia pinnata, Manilkara hexandra, and Pyrus pyrifolia seeds prepared by microwave assisted extraction method, and the violet pigment- violacein extracted from Chromobacterium violaceoum were screened for their antibacterial activity against Streptococcus mutans.M. hexandra extracts were able to inhibit both the test strains of S. mutans used in this study with minimum inhibitory concentration (MIC) ranging from 600-800 µg/mL. These extracts exerted bactericidal action against S. mutans with minimum bactericidal concentration (MBC) of 600-900 µg/mL. Acetone extract of M. hexandra seeds registered highest average total activity of 231.20 mL/g. Extraction efficiency was found to have a moderately good correlation with antibacterial activity. Violacein exerted bactericidal action with MIC and MBC of less than 2 µg/mL against both the strains.

Microwave assisted extraction (MAE) was investigated for extraction of total phenolic compounds (TPC expressed as gallic acid equivalents GAE) from the leaves of Pistacia lentiscus L. with maximized total phenolic yield using response surface methodology (RSM) coupled with a Box-Behnken design. The optimal MAE processing parameters were 46% ethanol, extraction time 60s, potency density 17.86W/mL, and liquid/solid ratio 28:1, with an extraction yield of 185.69±18.35mgGAE/gdw. The optimized MAE was compared with another emerging technology (ultrasound assisted extraction, UAE) and with conventional solvent extraction (CSE) giving higher extraction yields of TPC, total flavonoids and tannins and comparable antioxidant capacity (according to the radical ABTS assay).

Microwave and ultrasound-assisted extraction of phenolic compounds from C. limon peels were compared.•Response surface methodology successfully employed to optimize the extraction processes.•Better performance of microwave extraction than both ultrasound and conventional process. Ultrasound assisted extraction (UAE) and microwave-assisted extraction (MAE) were optimized (by response surface methodology, RSM) and compared for the recovery of total phenolic compounds (TPC expressed as gallic acid equivalents (GAE)) from Citrus limon peels. The optimized result for MAE was 48% ethanol as extraction solvent, 28:1. mL/g of solvent: solid ratio, 123. s and 400. W for irradiation time and power. The optimized result for UAE was 63.93% ethanol as extraction solvent, 40. mL/g of liquid/solid ratio, 15.05. min of holding time and 77.79% for amplitude. Maximum predicted TPC recoveries under the optimized conditions for MAE and UAE were 15.74 and 15.08. mg GAE/g respectively, which were close to the experimental values of 15.78. ±. 0.8 and 15.22. ±. 0.88. mg GAE/g, indicating suitability of the employed model and the success of RSM in optimizing the extraction conditions. The antioxidant activity determined by the DPPH and reducing power tests confirmed the suitability of MAE for the preparation of antioxidant-rich plant extracts.

The present work evaluated the use of Microwave Assisted Extraction (MAE) for the recovery of phenolic compounds from waste grape marc. MAE was carried out with 60% aqueous ethanol, investigating the effect of different microwave irradiation powers and times on the total polyphenols content and antioxidant power of the extracts. Process parameters of heating rate and boiling time were established for each irradiation power. MW power did not significantly influence the total phenols (TP) yield. Compared to conventional Solid Liquid Extraction, MAE reduced extraction time from 2 hours to 100 sec, achieving an equivalent TP yield (8.0±0.2 mg GAE/g grape skins). Antioxidant power of MAE extracts was slightly lower (2-10%) than SLE extracts probably due to thermal degradation.

Chromatography and extraction techniques, and also chemiluminescence have been utilized to develop new rapid and informative tools in the evaluation of long-term properties and environmental effects of polymeric materials. Methods were developed for classification of materials and for early and rapid degradation detection. Degradable polyethylene films were classified on the basis of their incorporated prooxidant systems using chromatographic fingerprinting of carboxylic acids, the dominating type of degradation product. The fingerprints were also shown to be useful for prediction of the degradation states and evaluation of the degradation mechanisms. Classification and prediction models were obtained by Multivariate Data Analysis, where the diacids were grouped according to both their type of prooxidant system and their state of degradation. The use of total luminescence intensity (TLI) measurements was also investigated as a means of classifying films and for the early detection of degradation. Comparisons were carried out with common techniques, e.g. FTIR and DSC, after both thermal and UV oxidation. TLI gave an earlier detection of degradation and was more sensitive than carbonyl index and crystallinity measurements to relative differences in degradation between the materials. It furthermore offered complementary information regarding changes in activation energies during the course of the degradation. The results were compared with the chromatographic fingerprints. A new way to evaluate the low temperature long-term stabilisation efficiency of antioxidants was investigated. A prooxidant was used to obtain catalytic oxidation, instead of using thermal acceleration, to evaluate the stabilisation efficiency of antioxidants at low temperatures but still during reasonably short aging times. Comparisons were made between polypropylene films stabilised with primary antioxidants (Irganox 1076, Irganox 1010 and α-tocopherol) with and without the prooxidant manganese ste, QC 20100929

Chromatography and extraction techniques, and also chemiluminescence have been utilized to develop new rapid and informative tools in the evaluation of long-term properties and environmental effects of polymeric materials. Methods were developed for classification of materials and for early and rapid degradation detection. Degradable polyethylene films were classified on the basis of their incorporated prooxidant systems using chromatographic fingerprinting of carboxylic acids, the dominating type of degradation product. The fingerprints were also shown to be useful for prediction of the degradation states and evaluation of the degradation mechanisms. Classification and prediction models were obtained by Multivariate Data Analysis, where the diacids were grouped according to both their type of prooxidant system and their state of degradation. The use of total luminescence intensity (TLI) measurements was also investigated as a means of classifying films and for the early detection of degradation. Comparisons were carried out with common techniques, e.g. FTIR and DSC, after both thermal and UV oxidation. TLI gave an earlier detection of degradation and was more sensitive than carbonyl index and crystallinity measurements to relative differences in degradation between the materials. It furthermore offered complementary information regarding changes in activation energies during the course of the degradation. The results were compared with the chromatographic fingerprints. A new way to evaluate the low temperature long-term stabilisation efficiency of antioxidants was investigated. A prooxidant was used to obtain catalytic oxidation, instead of using thermal acceleration, to evaluate the stabilisation efficiency of antioxidants at low temperatures but still during reasonably short aging times. Comparisons were made between polypropylene films stabilised with primary antioxidants (Irganox 1076, Irganox 1010 and α-tocopherol) with and without the prooxidant manganese ste, QC 20100929

Chromatography and extraction techniques, and also chemiluminescence have been utilized to develop new rapid and informative tools in the evaluation of long-term properties and environmental effects of polymeric materials. Methods were developed for classification of materials and for early and rapid degradation detection. Degradable polyethylene films were classified on the basis of their incorporated prooxidant systems using chromatographic fingerprinting of carboxylic acids, the dominating type of degradation product. The fingerprints were also shown to be useful for prediction of the degradation states and evaluation of the degradation mechanisms. Classification and prediction models were obtained by Multivariate Data Analysis, where the diacids were grouped according to both their type of prooxidant system and their state of degradation. The use of total luminescence intensity (TLI) measurements was also investigated as a means of classifying films and for the early detection of degradation. Comparisons were carried out with common techniques, e.g. FTIR and DSC, after both thermal and UV oxidation. TLI gave an earlier detection of degradation and was more sensitive than carbonyl index and crystallinity measurements to relative differences in degradation between the materials. It furthermore offered complementary information regarding changes in activation energies during the course of the degradation. The results were compared with the chromatographic fingerprints. A new way to evaluate the low temperature long-term stabilisation efficiency of antioxidants was investigated. A prooxidant was used to obtain catalytic oxidation, instead of using thermal acceleration, to evaluate the stabilisation efficiency of antioxidants at low temperatures but still during reasonably short aging times. Comparisons were made between polypropylene films stabilised with primary antioxidants (Irganox 1076, Irganox 1010 and α-tocopherol) with and without the prooxidant manganese ste, QC 20100929

The concentrations of three stabilizers-a hindered phenol (Irganox 1076), a hindered amine light stabilizer (Tinuvin 770) and a bifunctional stabilizer with chain-breaking hindered phenol and secondary amine and hydroperoxide-decomposing sulphide moieties (Irganox 565)-in crosslinked polydimethylsiloxane were varied using swelling solutions of the stabilizers at different concentrations. The concentration of the stabilizer in the rubber was assessed by UV-Vis spectroscopy of Soxhlet and microwave assisted extracts. Irganox 1076 and Tinuvin 770 were soluble in polydimethylsiloxane to at least 0.2-0.3 wt.%, whereas the solubility of Irganox 565 was considerably lower. The samples were exposed to GHz air plasma and the surface structures of the exposed samples were studied by X-ray photoelectron spectroscopy, and by optical and scanning electron microscopy after uniaxial stretching. The plasma exposure time required for the formation of an oxidised glassy layer increased in a linear fashion with increasing stabilizer concentration, suggesting that the consumption rate was constant in time during the plasma exposure. Tinuvin 770 showed the strongest overall protecting effect whereas Irganox 565 showed the strongest protecting effect per mass fraction of stabilizer. Irganox 1076 was of moderate efficiency. The results suggest that efficient protection towards air plasma is achieved with hindered amine stabilizers or with stabilizers combining chain-breaking and hydroperoxide-decomposing functions. Differential scanning calorimetry showed that Tinuvin 770 and Irganox 565 protected polydimethylsiloxane against thermal oxidation at elevated temperatures. The chemical consumption of these stabilizers followed basically the classical scheme with zero-order kinetics and a rate constant obeying the Arrhenius law., QC 20100525

Two nonconventional extraction techniques, microwave assisted extraction (MAE) and ultrasonication, were used to extract degradation products from polyolefins with enhanced degradability. High-density polyethylene/polypropylene blends with two different biodegradable additives (a granular starch/iron oxide mixture and Mater-Bi AF05H) were subjected to outdoor soil burial tests and removed at different periods of time between 0 and 21 months. The extracted products were analyzed by gas chromatography mass spectrometry (GC-MS). Ultrasonication was found to be a more suitable technique than MAE because of better reproducibility. In addition, higher amounts of certain products (e.g., carboxylic acids) were extracted by ultrasonication than by MAE. The degradation products extracted from the two blends were basically a homologous series of alkanes, alkenes, carboxylic acids, and alcohols. The amount of hydrocarbons (saturated and unsaturated) and alcohols remained basically the same as the degradation times increased. However, carboxylic acids tended to decrease slightly with the exposure time. Their concentration remained practically unchanged until 12 months of soil burial when a more significant decrease was noted. The quantitative analysis of the degradation products revealed for both samples a decrease in the amount of carboxylic acids with the exposure time, although the trend was different according to the additive used in each sample. For blends with Mater-Bi the amount of carboxylic acids was at a minimum after 12-month exposure in soil, which coincided with a minimum in the molecular weight distribution. After blends with granular starch/iron oxide were exposed to 3 months in soil, tetradecanoic acid was no longer detectable and the amount of hexadecanoic and octadecanoic acids decreased significantly. Solid-phase microextraction, a solvent-free extraction technique, was used to extract the degradation products that could have migrated to the soil from blends w, QC 20100525

The quality of recycled resins of high density polyethylene (HDPE) and polypropylene (PP) separated from mixed solid waste (MSW) were studied by analyzing the tentative low molecular weight contaminants. For that purpose a microwave assisted extraction (MAE) technique was developed using MDPE and two aromatic antioxidants (Irganox 1010 and Irgafos 168) as models. A 50:50 mixture of cyclohexane and isopropanol gave high recovery yields; 97% for Irgafos 168 and 93% for Irganox 1010 and short extraction times. Limonene, isopropylester of myristic and palmitic acids were examples of products identified in recycled HDPE. These compounds are typically fragrance and flavor constituents. In addition alcohols, esters, ketones were identified. Most of the substances are constituents of the packaging fillings at their first usage. But the possibility that contaminants may have entered the material by contact with other plastics is not excluded. The major category of compounds identified already in the virgin material is composed of aliphatic hydrocarbons (e.g. pentadecane, hexadecaned, 1-hexadenene), branched alkanes, branched alkenes and others. The same kind of compounds were also identified in the recycled materials at a similar concentration as in virgin ones. Virgin and recycled polyethylene contain also ethylbenzene and o-, m- and p-xylenes, where o-xylene had the largest peak of the four. The aromatic hydrocarbons are probably parts of additives, which degraded during extraction and sample preparation procedures. Aromatic hydrocarbons without functional groups, such as ethylbenzene and xylenes are considered highly toxic, but the height and area of their peaks suggest low concentrations. The concentration of these hazardous contaminants in the recycled resin is, however, approximately five times higher in recycled material, estimated by a comparison of the peak areas. Ethylbenzene and o-, m- and p-xylenes, o-xylene having the largest peak of the four were also identifie, QC 20100525

Experimental data are presented for the first time in support of a theoretical model of band broadening proposed by Blumberg (1997). This model addresses the effects of the compressibility of the mobile phase in gas chromatography and presents an equation derived from only two mutually independent variables. Solutions of decane and tridecane in hexane were analyzed at pressures ranging from 15 to 150 psi. Six different columns were used that varied in length, internal diameter and film thickness. Theoretical plate heights were obtained from this data and plotted versus the average linear carrier gas velocity (Golay type plots). These plots showed that at high pressures the Blumberg model fit the experimental data statistically significantly better than the earlier model proposed by Golay. The Blumberg model also accurately predicts the relationship between the optimum linear carrier gas velocity and the temperature. The second part of this work explores the scope and limitations of fast temperature programming in the fast GC analyses of various sample types. These samples included polycyclic aromatic hydrocarbons (PAHs), hydrocarbons and food samples. Programming rates of up to 1200° C/min were used. These fast programming rates were obtained by using "flash"â ¢ temperature programming, controlled by resistive heating of a metal tube that enclosed a capillary column. The precision of peak data was found to be good, less than 5% for peak areas and 4% for retention times. However, a slight, but statistically significant decrease in peak areas was seen above programming rates of 240° C/min. Microwave assisted extraction (MAE) was used to extract 2,6-di-(tert-butyl)-4-methylphenol, BHT, from chewing gum and breakfast cereal. The extraction was followed by a fast GC analysis (less than 4 minutes) using "flash"â ¢ temperature programming. MAE reduced the sample preparation time, from hours to minutes, and consequently reduced, the total analysis time. Extraction times lon

Reported here in is new analytical methodology for the determination of 90 emerging contaminants (ECs)in liquid environmental matrices (crude wastewater, final effluent and river water). The application of a novel buffer, ammonium fluoride improved signal response for several ECs determined in negative ionisation mode. Most notably the sensitivity of steroid estrogens was improved by 4–5 times in environmental extracts. Method recoveries ranged from 40 to 152% in all matrices and method quantitation limits (MQLs) achieved were [less than]1 ng L−1for numerous ECs. Development of a microwave assisted extraction(MAE) protocol as an additional sample extraction step for solid matrices enabled 63 ECs to be simultaneously analysed in digested sludge. To the authors knowledge this is considerably more than any previously reported MAE method. Here, MQLs ranged from 0.1–24.1 ng g−1dry weight. The application of MAE offers several advantages over pressurized liquid extraction including faster sample preparation, lower solvent requirements, and the ability to perform several extractions simultaneously as well as lower purchasing and running costs. To demonstrate the method’s sensitivity, application to environmental samples revealed 68 and 40 ECs to be above their respective MQL in liquid environmental samples and digested sludge, respectively. To date, this is the most comprehensive multi-residue analytical method reported in the literature for the determination of ECs in both liquid and solid environmental matrices.

In constructed wetlands, micropollutants can be removed from water by phytoremediation. However, micropollutant uptake and metabolism by plants here is poorly understood due to the lack of good analytical approaches. Reported herein is the first methodology developed and validated for the multi-residue determination of 81 micropollutants (pharmaceuticals, personal care products and illicit drugs) in the emergent macrophyte Phragmites australis. The method involved extraction by microwave-accelerated extraction (MAE), clean-up using off-line solid phase extraction and analysis by ultra-high-performance liquid chromatography tandem mass spectrometry. Development of the MAE method found the influence of studied variables on micropollutant recovery to be: extraction temperature > sample mass > solvent composition. Validation of the developed extraction protocol revealed that method recoveries were in the range 80-120% for the majority of micropollutants. Method quantitation limits (MQLs) were generally < 5 ng g-1 dry weight, demonstrating the sensitivity of the methodology. Application of the method to P. australis from a constructed wetland used to treat trickling filter effluent found 17 micropollutants above their MQL, up to concentrations of 200 ng g-1. Other than uptake, the presence of several metabolites (carbamazepine 10,11 epoxide, desvenlafaxine, 2-ethylidene-1,5-dimethyl-3,3-diphenylpyrrolidine, N-desmethyltramadol and norketamine) indicated that metabolism within the plant may also occur. This new analytical methodology will enable a process mass balance of the constructed wetland to be attained for the first time, and thus help understand the role of phytoremediation in micropollutant removal by such systems.

Reported here in is new analytical methodology for the determination of 90 emerging contaminants (ECs)in liquid environmental matrices (crude wastewater, final effluent and river water). The application of a novel buffer, ammonium fluoride improved signal response for several ECs determined in negative ionisation mode. Most notably the sensitivity of steroid estrogens was improved by 4–5 times in environmental extracts. Method recoveries ranged from 40 to 152% in all matrices and method quantitation limits (MQLs) achieved were [less than]1 ng L−1for numerous ECs. Development of a microwave assisted extraction(MAE) protocol as an additional sample extraction step for solid matrices enabled 63 ECs to be simultaneously analysed in digested sludge. To the authors knowledge this is considerably more than any previously reported MAE method. Here, MQLs ranged from 0.1–24.1 ng g−1dry weight. The application of MAE offers several advantages over pressurized liquid extraction including faster sample preparation, lower solvent requirements, and the ability to perform several extractions simultaneously as well as lower purchasing and running costs. To demonstrate the method’s sensitivity, application to environmental samples revealed 68 and 40 ECs to be above their respective MQL in liquid environmental samples and digested sludge, respectively. To date, this is the most comprehensive multi-residue analytical method reported in the literature for the determination of ECs in both liquid and solid environmental matrices.

In constructed wetlands, micropollutants can be removed from water by phytoremediation. However, micropollutant uptake and metabolism by plants here is poorly understood due to the lack of good analytical approaches. Reported herein is the first methodology developed and validated for the multi-residue determination of 81 micropollutants (pharmaceuticals, personal care products and illicit drugs) in the emergent macrophyte Phragmites australis. The method involved extraction by microwave-accelerated extraction (MAE), clean-up using off-line solid phase extraction and analysis by ultra-high-performance liquid chromatography tandem mass spectrometry. Development of the MAE method found the influence of studied variables on micropollutant recovery to be: extraction temperature > sample mass > solvent composition. Validation of the developed extraction protocol revealed that method recoveries were in the range 80-120% for the majority of micropollutants. Method quantitation limits (MQLs) were generally < 5 ng g-1 dry weight, demonstrating the sensitivity of the methodology. Application of the method to P. australis from a constructed wetland used to treat trickling filter effluent found 17 micropollutants above their MQL, up to concentrations of 200 ng g-1. Other than uptake, the presence of several metabolites (carbamazepine 10,11 epoxide, desvenlafaxine, 2-ethylidene-1,5-dimethyl-3,3-diphenylpyrrolidine, N-desmethyltramadol and norketamine) indicated that metabolism within the plant may also occur. This new analytical methodology will enable a process mass balance of the constructed wetland to be attained for the first time, and thus help understand the role of phytoremediation in micropollutant removal by such systems.