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Barley (Hordeum vulgare L.) is one of the major cereal crops worldwide. It is grown not only to be used as fodder but also for human consumption. Barley grains are a great source of phenolic compounds, which are particularly interesting for their health-promoting antioxidant properties, among other benefits. Two extraction methods, namely ultrasound-assisted extraction (UAE) and microwave-assisted extraction (MAE), have been optimized and compared by using Box–Behnken design (BBD) to determine both the antioxidant power and the phenolic compound levels of the extracts. Three variables have been assessed based on these designs: solvent composition (% MeOH in water), temperature (°C), and sample-to-solvent ratio (mg sample mL−1 solvent). The solvent composition used and the interaction between the solvent and the temperature were the most significant variables in terms of recovery of phenolic compounds and antioxidant capacity of the extracts. Short extraction times, a high precision level, and good recoveries have been confirmed for both methods. Moreover, they were successfully applied to several samples. Significant differences regarding the level of phenolic compounds and antioxidant power were revealed when analyzing three different barley varieties. Specifically, the amounts of phenolic compounds ranged from 1.08 to 1.81 mg gallic acid equivalent g−1 barley, while their antioxidant capacity ranged from 1.35 to 2.06 mg Trolox equivalent g−1 barley, depending on the barley variety. Finally, MAE was found to be slightly more efficient than UAE, presenting higher levels of phenolic compounds in the extracts.

This study investigated the effect of extraction method and the choice of solvent on the phenolic substance and antioxidant activity of certain varieties of grain seeds (Hordeum vulgare L.). In this ponder, three diverse solvents were used, specifically acetone, ethanol, and methanol, and three extraction methods were utilized to extract the phenolic substance ultrasound extraction, Soxhlet, and maceration. The levels of total phenols (TPC), total flavonoids (TFC) and proanthocyanidins (PA) were decided. The results appeared that diverse solvents of different polarity had a major impact on polyphenol content and antioxidant activity; the highest TPC (1.990 mg EG/g of dried extract), PA (1.628 mg EC/g of dried extract) were obtained with acetone, the results of TPC and PA were in this order: 70% acetone extract > 70% ethanol extract > 70% methanol extract and the highest TFC (2.204 mg EQ/g of dried extract) were obtained with methanol, the results of TFC were in this order: 70% methanol extract > 70% acetone extract ≈ 70% ethanol extract. However, different extraction methods gave comparable results. In vitro antioxidant activities were assessed utilizing the DPPH radical scavenging capacity, The lowest IC50 value reflects the highest antioxidant potency, acetone extract showed the greatest ability to scavenge DPPH free radicals with an IC50 of 2.013 mg/ml, 2.024 mg/ml, 2.635 mg/ml, 3.428 mg/ml respectively observed in the varieties MASSINE, LOCALE, CASAMENCE, AMALOU, these results show that barley seeds of the two-row type (MASSINE and LOCALE) have a higher antioxidant activity compared to the six-row type (CASAMENCE and AMALOU). Ultrasonic extraction was better for extracting antioxidant molecules from barley seeds in comparison to soxhlet and maceration.

Blackberry (Rubus fruticosus) belongs to the Rosaceae family. It is very rich in essential and beneficial elements. In Morocco, despite its nutritional quality, this fruit remains among the forest species that are ignored. The present study has been focused on the physicochemical characterization of this species. The fruits have been harvested from the Mediterranean region of Morocco (Tangier-Tetouan-Al Hoceima). The analysis was made directly after the harvest for the determination of pH value, acidity, Total soluble solid, refraction index, total and reducer sugar levels. Results showed that the fruit is acidic (pH 4.65±0.32), rich in water (70%) and total sugars (27.43±2.67 mg/l). The variation of different physicochemical parameters in all fruit samples collected from different sites may be due to geographical distribution, climatic and edaphic parameters.

In recent decades, landfill sites have been a potential source of contamination, which can hurt the environment due to the accumulation of heavy metals and processed organic products. In the Tangier landfill, the different types of wastes are missing any prior treatment or any soil of protection. This behavior constitutes a risk factor of contamination for the soil and groundwater. Between the waste and soil, many physicochemical and biological reactions occur. The objective of this work effort is to derive a global and in-depth characterization of the organic and mineral matter of the soil samples from the Tangier landfill. The study of organic matter (OM) in soils helps to understand the evolution of soil contamination. Eight samples of soil have been studied using a range of chemical and physical analytical methods. FT-IR spectroscopy and X-ray diffraction analyses have used to investigate the nature of organic matter. The analysis of heavy metals in the soil showed that there is a significant presence of Pb, Cd, As, Cr and Zn quantities which are mainly due to industrial waste.

A method for the extraction of phenolic compounds from grape seeds and skins using microwave-assisted extraction (MAE) was developed. Optimization of the effects of the extraction parameters in terms of the results of extraction was obtained using the response surface methodology. The parameters studied were extraction solvent (methanol, ethanol, acetone, and water), percentage of methanol in water, quantity of sample in relation to volume of extraction solvent (solid:liquid, 10-50 mg mL(-1)), power (100-500 W), magnetic stirring speed (0-100%), and extraction time (5-20 min). Finally, the repeatability and the intermediate precision of the method were determined. The best conditions proved to be: 65% methanol in water as an optimum extraction solvent; 0.5 g of grape skin or seed in a volume of 25 mL; a power of 500 W with the maximum stirring speed (100%); and an extraction time of 5 min. The phenolic compounds proved to be stable in the optimized extraction conditions. The resulting repeatability and the intermediate precision of the optimized method showed a relative standard deviation below 7%. The new method applied on Napoleon grape allowed for the determination of catechin (453.2 (mg kg(-1))), epicatechin (306.3 mg kg(-1)), caftaric acid (22.37 mg caffeic acid equivalents kg(-1)), dihydrokaempferol-glycoside (11.13 mg kaempferol equivalents kg(-1)), quercetin (18.28 mg kg(-1)), quercetin-3-glucoside (20.09 mg quercetin equivalents kg(-1)), and kaempferol-3-glucoside (11.10 mg kaempferol equivalents kg(-1))., This research was co-financed by the 2014-2020 ERDF Operational Programme and by the Department of Economy, Knowledge, and Business at the University of the Regional Government of Andalusia. Project reference: FEDER-UCA18-108366. Document

Phenol red (X-PR) and malachite green carbinol (MGC) are two textile finishing dyes, which are present in aquatic environments through industrial effluents. Due to the toxic nature of both dyes, they are harmful to human health. In the present study, two materials, barley seeds and the biochar of barley (Hordeum vulgare L.), were used to remove the dyes in an aqueous solution. The materials used are characterized by AFM, FTIR, SEM, XRD and EDX techniques. In this study, the parameters studied are the adsorbent dose, pH, initial adsorbate concentration and contact time. The maximum equilibrium time was found to be 90 min for all dyes. Kinetic studies revealed that the adsorption of X-PR and MGC on barley seeds (BS-HVL) and the biochar of barley (BC-HVL) followed pseudo-second-order kinetics and that both porous and intraparticle diffusion mechanisms were involved. The adsorption equilibrium data were well fitted to the Langmuir and Freundlich isotherm model for both materials, and the maximum adsorption capacity of monolayer and multilayers for X-PR and MGC were 71.642 mg g−1 and 50 mg g−1 on BS-HVL, and 44.843 mg g−1 and 121.95 mg g−1 on BC-HVL, respectively. The thermodynamic results reveal that the dye removal on barley was endothermic and spontaneous in nature.

The aim of this study was to characterize the phytochemical content as well as the antioxidant ability of the Moroccan species Chamaerops humilis L. Besides crude ethanolic extract, two extracts obtained by sonication using two solvents with increased polarity, namely ethyl acetate (EtOAc) and methanol-water (MeOH-H2O) 80:20 (v/v), were investigated by both spectroscopy and chromatography methods. Between the two extracts, the MeOH-H2O one showed the highest total polyphenolic content equal to 32.7 ± 0.1 mg GAE/g DM with respect to the EtOAc extract (3.6 ± 0.5 mg GAE/g DM). Concerning the antioxidant activity of the two extracts, the EtOAc one yielded the highest value (1.9 ± 0.1 mg/mL) with respect to MeOH-H2O (0.4 ± 0.1 mg/mL). The C. humilisn-hexane fraction, analyzed by GC–MS, exhibited 69 compounds belonging to different chemical classes, with n-Hexadecanoic acid as a major compound (21.75%), whereas the polyphenolic profile, elucidated by HPLC–PDA/MS, led to the identification of a total of sixteen and thirteen different compounds in both EtOAc (major component: ferulic acid: 104.7 ± 2.52 µg/g) and MeOH-H2O extracts (major component: chlorogenic acid: 45.4 ± 1.59 µg/g), respectively. The attained results clearly highlight the potential of C. humilis as an important source of bioactive components, making it a valuable candidate to be advantageously added to the daily diet. Furthermore, this study provides the scientific basis for the exploitation of the Doum in the food, pharmaceutical and nutraceutical industries.

The valorization of biomasses as a source of second generation biofuels is one of the future projects. The valorization, of seeds and shells of cistus ladaniferus as a source of biofuel by the thermal way, pyrolysis in fixed bed under the optimal conditions of temperature and heating speed present very encouraging results. The characterization of the liquid obtained by different analytical methods such as XPS, Elemental Analysis, FTIR, enriches the study. The calorific values of the two bio-oils of seeds and their shells obtained by pyrolysis at 450°C with a heating rate of 21°C min−1 and 40°C min−1 are of the order of 37.05 and 37.93 respectively. This work consisted in valorizing one of the forest rejects, in this case the seeds of cistus ladaniferus which are shrubs generally distributed in the Mediterranean ecosystem, by transforming its oil into biofuel (biodiesel). The fixed bed pyrolysis of these rejects also has the advantage of having a low environmental impact in terms of greenhouse gas emissions.

The current work was carrying out to quantifie the total phenolic, flavonoids also proanthocyanidins contents. The phytochemicals, GC-MS analysis antioxidant and antibacterial activity of Curcuma rhizomes extracts, and they were evaluated using standard methods of determination of Phenolic contents, antioxidant, and antibacterial activity. The extracts were obtained by Ultrasonic-assisted extraction (UAE), the quantification of polyphenolic, flavonoids and proanthocyanidins contents presented a important value regarding the ethanolic extract (15.3g GAE/100g), (8.5 g CE/100g), (20.31 g TE/100g), respectively, also the antimicrobial inhibitory effect showed a remarkable activity, in addition GC-MS analysis of the extracts exposed the existence of indole, phytol and other important compounds of interest and showed better radical scavenging activity than the control in this study. Most of the phytochemicals present and some of the compounds revealed by GC-MS analysis, which are biologically active with physiological activities, could be the source of the antioxidant and antibacterial activity of the sample. They might as well be responsible for the pharmacological propreties derived from our samples. This study revealed the pharmacological importance, antimicrobial and antioxidant inhibitory potential of the extracts of Curcuma longa.L.

Emerging contaminants are recently uncovered in natural currents duo to human and industrial activities. Most of them have no legal standard and can probably cause damaging effects in aquatic life at relevant concentrations. The conventional wastewater treatment plant (WWTP) is not always effective for the removal of these huge classes of pollutants and so further water treatments are necessary. In this work, we applied the powdered activated carbon adsorption process to eliminate the selected emerging pollutants, Theobromine and two antibiotics commonly used in Spain: Amoxicillin (AMX) and Penicillin G (Peni G). Different experimental conditions such as pH and temperature, initial concentration, the amount of biomass, and contact time were studied to obtain the best removal conditions. The different contaminants were detected by ultra-performance liquid chromatography and mass spectrometry (UPLC-MS). The whole results obtained confirm the effectiveness of the process of adsorption for the purification of the liquid effluents charged with antibiotics and stimulant. The results we have obtained indicate that coconut shell activated charcoal allows better retention of this compound after 90 minutes of contact and that the elimination yields evolve with the mass of activated charcoal introduced. Furthermore, it has been shown that the initial concentration of contaminants and the variation in pH considerably influence the binding of theobromine, penicillin, and amoxicillin molecules to the sites of powdered activated charcoal. The overall results showed that the adsorption kinetics of three contaminants on activated carbon is well described by the second-order model, and the adsorption isotherms of the absorbent/absorbate systems studied are described satisfactorily by the Langmuir model.

Bioactive compounds in citrus fruits have been demonstrated to be protective against chronic diseases such as cancer and heart disease, but their degrees may be influanced by postharvest treatments as for example storage and irradiation treatment. Irradiation might ensure natural product decontamination, while maintaining their chemical, organoleptic, nutritional and bioactive qualities In this work, citrus fruits were subject to gamma irradiation at 0, 0.25,0.50 and 1 KGy/h and then stored at 4°C for 30 days, Phenolics, Flavonoid, tanins contents, and antioxidant activity were evaluated at regular intervals during storage. Results demonstrated that treatment by gamma radiation could preserve and have no impact on the phenolic content of citrus fruits during the storage by contrast irradiation treatments persuade the degradation on phenolics content and indicated the increasement of the antioxidant activity mainly on citrus treated at 1kGy/h, These results pointed out that gamma radiation at 0.50 kGy/h can be applied as safe and environmental friendly post-harvest treatment of citrus to preserve their bioactive compounds

Rubus fruticosus L. is a widespread shrub species which has recently attracted a great attention due a plethora of different pharmacological activities. A comparative study of the volatile profile and polyphenols along with the antioxidant activity of 27 blackberries collected in 3 different locations of the Tangier–Tetouan–Al Hoceima region in Northern Morocco, between June and August 2018, is reported. In terms of antioxidant activity, the highest IC50 values were attained for the Rubus fruticosus EtOAc extract coming from Beni Messaouar (2.5 mg/mL ± 0.01). Concerning the volatile content of the Rubus fruticosus n-hexane extract belonging to Beni Messaouar, a total of 42 compounds were detected and oleic acid turned out to be the most abundant one (14.49%), whereas among the 29 polyphenols detected in the Rubus fruticosus EtOAc extract, coming from the same location, quercetin-3-O-glucoside occurred in major concentration (364.58 mg/kg). This is the first report on the physico-chemical and phytochemical properties of Moroccan Rubus fruticosus highlighting how these fruits do have a great potential as natural source of antioxidant compounds to be used as a nutraceuticals or functional foods.

Wild jujube &ldquo, Ziziphus lotus (L.) Desf.&rdquo, belongs to the Rhamnaceae family and is a traditionally herbaceous medicinal plant. It is very common in arid and semi-arid regions and is currently used for its antidiabetic, sedative, analgesic, anti-inflammatory and hypoglycemic activities. The aim of the present work was to characterize the physico-chemical properties and the phytochemical profile of wild jujube sample collected from the Guercif region, in order to determine the polyphenolic compounds and the antioxidant ability Analyses were carried out directly after the harvest for the determination of pH, refractive index, total soluble solid (&deg, Brix), dry matter, sugar/acidity, total sugars, reducing sugars, as well as lipid and protein content. Results showed that the investigated fruit is acidic (pH 4.9 &plusmn, 0.23) and rich in sugars (80.2 g/100 g &plusmn, 3.81). The GC-MS analysis of the fruit revealed a number of volatile compounds, as many as 97, belonging to different chemical classes. The HPLC-DAD-ESI/MS analysis showed the presence of a total of 20 polyphenolic compounds in both EtOAc and MeOH-water extracts. Among them, p-Hydroxybenzoic acid was the most abundant in the EtOAc extract (185.68 &micro, g/100 mg &plusmn, 0.5) whereas Quercetin 3-O-rhamnoside-7-O-glucoside was found in higher amounts in the MeOH-water extract (25.40 &micro, 0.5). These components have medical interest, notably for human nutrition, as well as health benefits and therapeutic effects. Therefore, Moroccan jujube &ldquo, Zizyphus lotus (L.)&rdquo, fruit may have potential industrial applications for food formulations.

The present study aimed to validate a control method on the gas chromatography system (GC) based on the experimental design strategy, to examine the changes and correlation between the fermentation process and the quality of alcoholic and non-alcoholic beer product, especially the formation of diacetyl. On the other hand, spectrophotometric methods were applied to the determination of polyphenols content and the potential antioxidant activity of beer during different fermentation processes. with this aim, three modes of barley fermentation were used, specifically classical fermentation, stopped fermentation and thermal process. The results showed that the different fermentation modes had a major impact on diacetyl production. The highest concentration was obtained using stopped fermentation 0.36 mg/L, the lowest concentration value 0.07 mg/L was detected using the thermal process. Monitoring the increase of oxygen concentration between fermentation, filtration, and filling of the final product (32, 107, 130 ppm, respectively) has a significant impact on the concentration of diacetyl. The obtained results of spectrophotometric analysis showed that the total antioxidant activity changed during beer fermentation process and demonstrate that the extend of the antioxidant activity was very much dependent on the total polyphenolic content with a higher value in Hopped wort (13.41%, 65 mg GAE 100 mL−1, 28 mg CE 100 mL−1) for antioxidant potential, total phenolic content, and total flavonoids content, respectively, whereas the lowest values was detected in Non-alcoholic beer using thermal process (7.24%, 35 mg GAE 100 mL−1, 10 mg CE 100 mL−1) for antioxidant potential, total phenolic contents, and total flavonoids contents, respectively. Based on the results achieved, we reveal the impact of the fermentation process on the nutritional value of the final product.

Pollution from plastics and their slow degradation are current problems that require urgent solutions. The natural degradation of plastics leads to its fragmentation, resulting not only in microplastics (MPs) but also in nanoplastics (NPs). In recent years, research and monitoring of MPs and NPs concentrations has increased. The monitoring of their concentrations in the environment, sampling sites, detection and quantification methods are not standardised due to the inherent properties of the materials and the origin of the samples, which tends to make the comparison of data between different studies difficult. In this study, we developed an H2O2-enzyme protocol for the extraction of MPs from sludge based on existing analytical methods in the literature, from sampling to quantification and detection. Our laboratory study consists of four protocols used to verify MPs recovery from doped sludge samples containing three polymers (polypropylene, polyethylene terephthalate and nylon). To emphasise the relevance of the optimal protocol, a triplicate test was performed for each of these protocols, all of them using sieve fractions between 100 and 500 μm, while isoporous polycarbonate membranes were used for the filtration of the samples. The percentage polymer distribution of H2O2-enzyme protocol was similar to the control (42% ± 8.49; 38% ± 2.83; 16% ± 11.31), with some limitations for the larger fraction. Data collection was carried out by optical visualisation and chemical identification using Fourier-transform infrared spectroscopy to record polymer spectra obtained for potential interpretation. Finally, a test was conducted to try all protocols on a real sludge from a local plant to confirm their efficiency.

The aim of this study is to find out the degree of resemblance between the microstructure of a ceramic industry sludge based geopolymer and Metakaolin based geopolymer, in order to use this type of industrial sludge in some applications as a raw material instead of Metakaolin. The studied sludge is collected from a local industry manufacturing sanitary ceramic products. It 's generated during the treatment of its industrial wastewater. The structural change of geopolymer products is followed by FTIR spectroscopy, XRD and TEM analysis. Compressive strength of geopolymer specimens, prepared from the two raw materials, depends on the Na 2 O/Al 2 O 3 molar ratio. XRD analysis of calcined industrial sludge based-geopolymer and Metakaolin based-geopolymer, confirms the amorphous nature of the new formed phase. TEM micrographs of two kinds of raw materials based-geopolymer reveal one type of reacted region. Infrared spectroscopy shows that the behavior of the calcined industrial sludge vis-a-vis the sodium silicate solution is similar to that of Metakaolin.

The ferromagnetic resonance (FMR), spectra in the frequency range up to 12 GHz has been investigated as a function of applied DC magnetic field (up to 80 kA/m) for single-phase CoFe-based Pyrex-coated microwire as well as for biphase microwires after depositing an outer shell, with hard (CoNi) and soft (FeNi) magnetic character, respectively. In addition, a parallel study on the low-frequency magnetic hysteresis loop of all these samples has been performed. In particular, we have focused on the influence of the thickness of the insulating Pyrex layer and magnetic character of the outer magnetic phase. For single-phase microwires, the increase of the Pyrex thickness results in a continuous strengthening of the circular magnetoelastic anisotropy of the CoFe-based core as deduced from FMR and confirmed by low-frequency measurements. For biphase microwires three absorption peaks are observed: two of them can be ascribed to each magnetic phase since FMR frequencies obey the Kittel condition for a thin film. A third absorption peak is observed at lower frequencies that does not follow such an equation and can be ascribed to a pure geometrical effect of these biphase microwires.

Evaluation was made of four extraction techniques (maceration with magnetic stirring, ultrasound-assisted extraction, microwave-assisted extraction, and extraction with pressurised liquids) to obtain polyphenolic extracts from pine seeds. The technique and temperature conditions that produce extracts containing the largest quantity of polyphenols were determined. Extraction assisted by microwave and extraction with pressurised liquids at temperatures >100 °C gave the best results. The correlation between the antioxidant activity of the extracts and the quantity of polyphenols that they contain has also been determined; a direct relationship between these two variables was found in the majority of extracts. The general biological activity of the extracts was also evaluated using the etiolated wheat coleoptile bioassay; extracts obtained with pressurised liquids, and with maceration under agitation, were the most bioactive. An inverse relationship between the degree of bioactivity and the extraction temperature was found.

This work analyses and models the dehydration kinetics for whole and sliced strawberries during freeze-drying. A Virtis 35L Gardiner lyophyliser was used. Freeze-drying was carried out at various hotplate temperatures and several product thicknesses. It was observed that increasing hotplate temperature from 30°C to 70°C during the course of freeze-drying led to reducing the process from 48h to 36h for whole strawberries and from 12h to 8h for the slices, stable dry products being obtained. Studying several strawberry freeze-drying parameters showed that temperature has an important effect on reducing the process’ duration. It lowers the process’ cost whilst preserving dry fruit quality, thereby opening up the field by applying this technology to treating new food products.

The stability of 22 phenolic compounds of different families (benzoic acids, benzoic aldehydes, cinnamic acids, catechins, coumarins, stilbens and flavonols) has been studied under conditions of microwave-assisted extraction. The influence on the stability affected by the working temperature between 50 and 175 degrees C has been evaluated, and it has been concluded that all the compounds studied are stable up to 100 degrees C, whereas at 125 degrees C there is significant degradation of epicatechin, resveratrol and myricetin. Conclusions have been drawn on the relationship between the chemical structure and the stability of the compounds; it has been found that those that have a greater number of hydroxyl-type substituents are more easily degraded under the extraction conditions.

In this work three chromatographic methods were developed to reduce the total time of the analysis of main compounds in Aloe vera extracts. The first method was developed in a regular reverse phase chromatographic system using a particulate reverse phase C-18 column. Methods already published were used as a starting point for the development of the new method. All the compounds were separated in 32 minutes. The second method was developed in a regular reverse phase chromatographic system employing a monolithic type column. Using a 4.5 mL min−1 flow, the total time of analysis was reduced to 6 minutes with very similar resolution values. The third method was developed in an ultraperformance liquid chromatographic system, and the final time for the analysis of the phenolic compounds was reduced to 4 minutes. The analytical properties of the three chromatographic methods were compared for the main compounds in the chromatograms. Robustness of the three new methods was also checked with regard to the injection volume and the amount of methanol in the sample. A fast method (4 min) is then available for bioactive compounds from Aloe vera determination.

The development of a rapid, reliable and reproducible LC method for the determination and quantification of 13 polyphenols (gallic acid, protocatechuic aldehyde, gentisic acid, catechin, vanillinic acid, caffeic acid, vanillin, epicatechin, syringaldehyde, p-coumaric acid, ferulic acid, sinapic acid and resveratrol) in grapes and derived products is reported. The polyphenols were separated in less than 8 min. Employed was an RP-18e (100 mm × 4.6 mm) monolithic type column. A gradient method with the following solvents was utilised for the chromatographic separation: A: 90% water, 2% acetic acid in methanol, and B: 90% methanol, 2% acetic acid in water. Two detectors in series were employed: a UV–Vis detector and a fluorescence excitation/emission detector. Influence of temperature (15–40 °C) and solvent flow rate (2–5 mL min−1) on the separation were studied, and 25 °C and 2.5 mL min−1 were found to be the optimum conditions. The relative standard deviations of the resulting peak areas, for both intra- and inter- experiments, were less than 2.4 and 2.6%, respectively. Finally, the developed method has been utilised for the quantification of the polyphenols in real samples.

A kinetic study of the thermal decomposition of poly{1-acetoxy-1-[4-(2-chloroethyl)phenyl]-ethylene} (1) was carried out by thermogravimetry. Two stages, well separated, are observed. The first one begins at 140°C. The corresponding decomposition reaction is a superposition of two reactions: loss of acetic acid and partial depolymerization. The main volatile products released in this first stage, identified by gas chromatography/mass spectrometry coupling, are chiefly acetic acid and a small quantity of p-(2-chloroethyl)acetophenone; there is no monomer from the monomeric unit. As in case of other poly(para-substituted α-acetoxystyrenes) the solid residue is poly[p-(2-chlorethyl)phenylacetylene] (5) of low molar mass, soluble in all usual organic solvents. No auto-catalytic mechanism was found during this first stage, unlike in case of poly(vinyl acetate). The reaction order is one, over a wide range of conversion. The activation energy was found to be about 145,6 kJ/mol and the pre-exponential factor 1,6 · 1015 min−1. An explanation for the insolubility of the residues, obtained by thermal degradation of some poly(p-chloroalkylstyrenes), is proposed.

Four enol esters with a styrene skeleton (3a–d) were synthesized in two steps from commercial products and polymerized or copolymerized with styrene as a comonomer. The polymers and copolymers (7 and 8) were characterized. They are stable up to 140°C and lose acetic acid upon heating. Chemical modifications, such as nucleophilic substitutions with cyanide ions or nucleophilic addition of butyllithium, were studied.

Results from a systematic study of the factors affecting extraction of cis-verbenol and verbenone from pine seeds are presented. Five extraction conditions were investigated: extraction solvent, method of extraction, extraction temperature, volume of solvent, and the ratio of the mass of sample to the amount of extraction solvent. The resulting optimized method uses magnetic-stirring-assisted extraction of pine seeds (5 g) with ethyl acetate (75 mL) for 20 min, at room temperature. RSDs were less than 5% for both compounds. GC–FID was used for quantification of cis-verbenol and verbenone in the extracts.

The stability of Ochratoxin A during its extraction using different extraction techniques has been evaluated. Microwave-assisted extraction and pressurised liquid extraction, in addition to two other reference methods of extraction, i.e. ultrasound-assisted and magnetic stirring-assisted extraction, were evaluated. The effect of extraction temperature using the cited techniques was checked. The results show that Ochratoxin A can be extracted using microwave-assisted extraction at temperatures up to 150 degrees C without degradation. Pressurised liquid extraction can be used at temperatures up to 100 degrees C, for extraction times of less than 30min. Further, both ultrasound-assisted extraction and magnetic stirring extraction can be applied at temperatures up to 65 degrees C. High-performance liquid chromatography combined with fluorescence detection using a Chromolith RP-18e column at a flow rate of 5mL min(-1) was used to quantify the Ochratoxin A. The retention time for the Ochratoxin A was 1.3min. The limits of detection (LOD) and of quantification (LOQ) were 0.03 and 0.10microg L(-1), respectively.