Search

Following the marked increase of perylene concentration in southern coast of Caspian Sea, waterbird eggs were used as biomonitoring agents. Surface sediments and eggs of five bird species were collected from colonies in Anzali Wetland in the above coast for perylene analysis. The perylene concentrations in sediment and egg samples ranged within 70.6–204.4 and 25.5–43.2 ng/g dw, respectively. Diagnostic perylene ratios showed that the perylene found in all samples was of biogenic origin, possibly developing from terrestrial materials. The combination pattern of perylene was found to be similar in all samples. Conclusively, perylene observed in the area was transmitted from sediments in breeding areas into the eggs, so the eggs are biomonitoring agents and the prevalence of oxic conditions in surface sediments limits formation of perylene, reflecting perylene formation in the catchment area. We found that perylene distribution in surface sediments follows irregular patterns, representing significant effects from local inputs. [ABSTRACT FROM AUTHOR]

Abstract: Microwave-assisted hydrodistillation (MAHD) is an advanced hydrodistillation (HD) technique utilizing a microwave oven in the extraction process. MAHD of essential oils from the aerial parts (tops) of Thymus vulgaris L. (common thyme) was studied and the results were compared with those of the conventional HD in terms of extraction time, extraction yield/efficiency, chemical composition, quality of the essential oils and cost of the operation. MAHD was superior in terms of saving energy and extraction time (75min, compared to 4h in HD). Scanning electron microscopy (SEM) of thyme leaves undergone HD and MAHD provided evidences as to a sudden rupture of essential oil glands with MAHD. Gas chromatography–mass spectrometry analysis of the extracted essential oils indicated that the use of microwave irradiation did not adversely influence the composition of the essential oils. MAHD was found to be a green technology. [Copyright &y& Elsevier]

Abstract: Hyssopus officinalis L. (hyssop) as a food ingredient has its own importance in flavor industry and also in sauce formulations. Supercritical fluid extraction (SFE) of hyssop, cultivated in Iran, was performed at various pressures, temperatures, extraction (dynamic and static) times and modifier (methanol) concentrations using an orthogonal array design with an OA25(55) matrix conditions. Pressure, temperature and modifier in the SFE system influenced the extraction yield. Also, the composition of the extracted oils was greatly impacted by the operating conditions. Main components of the extracts under different SFE conditions were sabinene (4.2–17.1%, w/w), iso-pinocamphene (0.9–16.5%) and pinocamphene (0.7–13.6%). The extraction of sabinene, for example, was favored at 100atm, 55°C, 1.5% (v/v) methanol, 30min dynamic time and 35min static time. Use of SFE under different conditions can allow targeting the extraction of different constituents. [Copyright &y& Elsevier]

Highlights • Crude melon extract (CME) was investigated as a new source of enzyme compared to a commercial enzyme, Alcalase. • Kilka protein hydrolysates (KPH) yielded high protein content and low fat. • Functional properties of KPH were related to the degree of hydrolysis. • Alcalase hydrolysis produced higher protein recovery and hydrolysis rate. • The KFH made by CME showed better functional properties than those of Alcalase. Abstract The enzymatic hydrolysis (at 2.5, 5.0, 10.0, and 15.0% degree of hydrolysis, DH) of kilka fish (Clupeonella cultriventris caspia) was investigated using a crude melon extract (CME) as well as a commercial serine protease (Alcalase). Hydrolysates from both enzymatic treatments were analyzed for their antioxidant and functional properties. The hydrolysis resulted in increased antioxidant activities of kilka fish protein hydrolysates and the highest antioxidant activity was obtained for the CME hydrolysates with 5.0% DH level. Both treatments improved the protein solubility level to >65% within a pH range of 2.0–10.0. At a given DH level, CME hydrolysates showed higher oil and water holding capacities than Alcalase hydrolysates. Hydrolysates from CME exhibited better emulsifying properties compared to those prepared by Alcalase, particularly at low DH (2.5 and 5.0%). According to the results of this study, CME can be suggested as a new source of proteolytic enzymes for fish protein hydrolysis. [ABSTRACT FROM AUTHOR]

In this study, acidic extraction (citric acid) was used for the extraction of pectin from melon peel. A central composite design (CCD) was applied to study the effect of temperature (35–95 °C), time (40–200 min), pH (1–3) and solvent to sample ratio (10–50 v/w) on the yield and degree of esterification (DE). The results showed that the yield and DE ranged from 2.87 to 28.98% and 1.33–29.33%, respectively. Also, the highest extraction yield (29.48 ± 1.7%) was obtained under optimal conditions (pH of 1, temperature of 95 °C and ratio of 10 v/w after 200 min). The protein, ash, carbohydrate and galacturonic acid content of pectin obtained under optimal conditions were about 1.5, 3.5, 10 and 48%, respectively. Rheological experiments determined that melon peel pectin dispersions behaved as a weak gel at concentrations of 1%w/v. The emulsifying activity was 35% and also, the emulsion stability was higher at 4 °C than at 23 °C. [ABSTRACT FROM AUTHOR]

Abstract: In the present work, two extraction techniques and two green solvents have been tested to obtain γ-linolenic acid (GLnA)-enriched fractions from Arthrospira platensis (Spirulina). Expanded ethanol with CO2 (gas expanded liquid extraction, GXL) and pressurized liquid extraction (PLE) using mixture of ethanol:ethyl lactate were tested and optimized chemometrically. Results obtained allow understanding the effects of the different factors involved in the tested processes and providing the optimum conditions to achieve the maximum total yield of lipids and also maximum GLnA recovery (%, w/w). Total yields up to 20.7% (w/w), were obtained under optimum PLE conditions considering 20.7MPa pressure, 180°C temperature and 15min extraction time and a solvent composition of ethanol:ethyl lactate (50:50, v/v), under which GLnA recoveries of 68.3% from the original amount was achieved. GXL provided total yields of 7.4% (w/w) and GLnA recovery of 35.3%, both of which were lower than those obtained by PLE. [Copyright &y& Elsevier]

Abstract: Important health-promoting compounds, including six types of anthocyanins, phytoestrogenic flavonoids and ellagic acid were determined individually in pomegranate juices (Punica granatum L.) of eight Iranian cultivars by high performance liquid chromatography coupled to UV–vis detector (HPLC–UV) using individual calculation from the peak area based on standard curves of each component. Total phenolics and antioxidant activities were determined by Folin–Ciocalteu and 2,2-diphenyl-1-picrylhydrazyl (DPPH) methods, respectively, and compared among the cultivars. The predominant anthocyanins were delphinidin 3,5-diglucoside (372–5301mg/l) followed by cyanidin 3,5-diglucoside (242–2361mg/l), delphinidin 3-glucoside (49–1042mg/l) and pelargonidin 3,5-diglucoside (7–90mg/l), respectively. The highest level of total tannins was found in Sweet Alak cultivar (3mg/l). Saveh Black Leather showed the highest level of ellagic acid (160mg/l). Antioxidant activity varied among the cultivars (18–42 Trolox equivalents antioxidant capacity) and was directly related to the total phenolics in each type of juice. [Copyright &y& Elsevier]

Abstract: An analytical study on the fatty acids, physicochemical characteristics, phenolic compounds, tocopherol content and antioxidant activities of walnut oils extracted by different extraction methods (maceration, Mac; modified Bligh–Dyer, MBD; and cold-press, CP) was conducted. Antioxidant activity of oil was measured by 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2′-azinobis (3-ethylbenzthiazoline sulfonate) (ABTS) radical scavenging capacity and β-carotene bleaching assays. Results showed that fatty acid content was not influenced by extraction method. MBD method was found to be the best process for extracting oil with a favorable quality characteristics when compared to Mac and CP. Higher total phenolics content (TPC), ortho-diphenol content (ODC) and total tocopherol content (TTC) and DPPH and ABTS scavenging capacities were also obtained with MBD. According to both principal component and correlation analyses, TPC and ODC were correlated with the β-carotene bleaching activity and TTC was correlated with the ABTS of the oils extracted by the different methods in the current study. [Copyright &y& Elsevier]