The Influence of Season on the Gonad Index and Biochemical Composition of the Sea Urchin Paracentrotus lividus from the Golf of Tunis

Seasonal variation in the gonad weight and biochemical composition of the sea urchin Paracentrotus lividus from the Golf of Tunis (Tunisia) were studied between September 2003 and August 2004. The highest gonad indices occurred in March (16.71%). The spawning period occurred between April and July and resulted in a fall in gonad indices to low level (7.12 ± 0.12%). Protein constituted the main component of the gonad, and lipid and carbohydrate were found at appreciable amounts. Consistent with the gonad cycle, sea urchin biochemical components showed clear seasonal variation with a significant decrease during the spawning period. The polyunsaturated fatty acid (PUFA) group was found at high level (40% of the total fatty acids). Of the PUFA group, eicosapentaenoic (C20:5 n − 3) and eicosatetraenoic (C20:4 n − 3) were the most abundant gonadal lipids. The level of PUFA was significantly affected by temperature variation showing an increase during the cold months and a decrease in the hot months

Classification of Southern Tunisian honeys based on their physicochemical and textural properties

This study investigated the physicochemical, rheological and textural properties of nine types of honey from different regions of southern Tunisia. Principal component and cluster analyses were used to classify the honeys into groups. The physicochemical results (water, proteins, total soluble solids, pH, free acidity, water activity, electrical conductivity, invertase activity, Hydroxymethylfurfural (HMF), vitamin C, lycopene and anthocyanins) were in accordance with those of the standards Established by the Codex Alimentarius. The invertase activity varied from 62.58 units/kg to 110.24 units/kg. The HMF values of the different types of honey ranged from 11.48 mg/kg in prickly pear honey to 25.56mg/kg in heather honey. Anthocyanin contents, lycopene and vitamin C contents ranged between 8.38 and 24.86 μg/L, 1.08 to 6.17 mg/kg and 30.71 to 129.38 mg/kg, respectively. The flow test confirmed the Newtonian behavior of all honeys, and their textural properties had very high extrusion forces varying from 113.50 g to 131.05 g. Cluster analysis (CA) and the biplot generated through PCA recognized four groups of honeys based on either the physicochemical parameters or textural attributes and only three groups based on color and sugar

Physicochemical and bioactive properties of six honey samples from various floral origins from Tunisia

The present study was undertaken to determine the physicochemical, biochemical, and antioxidant activities of Tunisian honey samples. All the extracted honey samples appeared to con- form to the European Legislation (EC Directive 2001/110) for all parameters. Mint honey, for instance, possesses significant pH value (p < 0.05), invertase activity, water, and protein contents. In addition, this study demonstrates that the color of the Tunisian honeys is highly variable and ranges from pale yellow to dark brown. The total phenolic, flavonoid and carotenoid contents sig- nificantly vary (p < 0.05). The highest values were found in mint honey, which has a very dark color. Correlations between the analyzed parameters are statistically significant (p < 0.05). The DPPH radical scavenging activity of rosemary honey was determined as lower (p < 0.05) than the other analyzed honey samples. Yet, the highest activity was detected in mint honey. The results suggest that Tunisian honeys could be beneficially used as a functional or nutraceutical substance as they prevent or moderate oxidative stress-related diseases

Probiotički jogurt od devinog mlijeka s dodatkom inulina: antibakterijsko, antioksidacijsko i antidijabetičko djelovanje

Similar to cow’s milk, camel milk also contains the essential nutrients as well as potentially therapeutic compounds with antihypertensive, and antioxidant properties. In the current study, camel milk was used for developing a new probiotic camel milk yoghurt with commercial prebiotic (inulin). The camel yoghurt samples were evaluated by monitoring the changes in some physicochemical properties (pH, total acidity and synerisis) and bacterial viability and survival of Limosilactobacillus fermentum CABA16 during storage. Besides, antibacterial, ⍺-amylase and ⍺-glucosidase inhibitions and antioxidant activities and the sensory evaluation of this novel product were assessed. The pH values of samples decreased whereas total acidity values increased throughout 21 days of storage and Limosilactobacillus fermentum CABA16 maintained good viability with counts higher than 107 CFU g-1 at the end of storage. α-Glucosidase and α- Amylase Inhibitions Water-Soluble Extracts were higher than 35 and 55% respectively in probiotic (PY), prebiotic (InY) and symbiotic (SY) camel yoghurts at the end of storage period. Moreover, the highest antioxidant activities of the WSEs from camel yoghurts were around 49 and 61% by DPPH and ABTS assays respectively. The fortified probiotic camel yoghurts exhibited comparable antibacterial activities with maximum diameter of 12±0.07 mm on Staphylococcus aureus and Listeria monocytogenes strains. Lastly, the addition of probiotic and inulin significantly improved the sensory characteristics, except the colour, of camel yoghurts.Devino mlijeko poput kravljeg sadrži esencijalne hranjive tvari kao i potencijalno korisne spojeve s antihipertenzivnim i antioksidativnim svojstvima. U ovom je istraživanju korišteno devino mlijeko kao sirovina za razvoj novog probiotičkog jogurta s komercijalnim prebiotikom (inulin). U uzorcima devinog jogurta tijekom skladištenja praćene su promjene nekih fizikalno-kemijskih svojstava (pH, ukupna kiselost i sinereza) te preživljavanje bakterija uključujući i soj Limosilactobacillus fermentum CABA16. Osim toga, proizvedeni uzorci jogurta su senzorski ocijenjeni te im je određivana su antibakterijska i antioksidacijska aktivnost, kao i sposobnost inhibicije α-amilaze i β-glukozidaze. Tijekom 21 dana skladištenja, pH vrijednosti uzoraka su padale, dok su vrijednosti ukupne kiselosti porasle, a soj Limosilactobacillus fermentum CABA16 pokazao je dobru sposobnost preživljavanja budući je na kraju skladištenja broj poraslih kolonija iznosio preko 107 CFU g-1. Inhibicije α-glukozidaze i α-amilaze u ekstraktima topljivim u vodi bile su veće od 35 odnosno 55 % u probiotičkom (PY), prebiotičkom (InY) i simbiotičkom (SY) devinom jogurtu na kraju razdoblja skladištenja. Štoviše, najveće antioksidacisjke aktivnosti ekstrakta topljivog u vodi (WSE) dobivenog obradom uzoraka devinih jogurta bile su oko 49 odnosno 61 % prema DPPH i ABTS testovima. Obogaćeni probiotički devini jogurti pokazali su slično antibakterijsko djelovanje na sojeve Staphylococcus aureus i Listeria monocytogenes, s maksimalnim promjerom zona inhibicije od 12±0,07 mm. U konačnici, dodatak probiotika i inulina značajno je poboljšao sva senzorska svojstva devinih jogurta osim boje

Chemical characteristics and compositions of red pepper seed oils extracted by different methods

The present work was undertaken to study the physicochemical characteristics, fatty acid, phenolic and tocopherol compositions as well as the antioxidant activities of red pepper seed oils extracted using different methods (soxhlet, cold-pressing, supercritical-CO2 and microwave-assisted extraction process). The results showed that the red pepper seeds were (on a dry-weight basis): ash 3.05%, water 6.63%, oil 18.39%, protein 28.33%, and total carbohydrate 43.60%. In addition, the results revealed that the predominant fatty acids were linoleic, palmitic and oleic acids. The highest and lowest contents of linoleic acid (76.54%) were found in microwave-assisted (76.54%) and soxhlet (73.65%) extracted pepper seed oils, respectively. &lt; Gamma&gt;-tocopherol was the main tocopherol at 278.65 mg/100 g seed oil, followed by &lt; alpha&gt;-tocopherol and &lt; delta&gt;-tocopherol. Nevertheless, high content in total tocopherols was found in microwave extracted red pepper seed oils. The lowest and highest values of oxidative stability were 1.25 and 11.26 h for soxhlet and microwave-assisted extracted seed oils, respectively. Overall, the high antioxidant activities of microwave-assisted extracted seed oil suggest that it could be economically used as valuable natural products for industrial, cosmetic, and pharmaceutical utilizations

Optimization of the Extraction Process by Response Surface Methodology of Protein Isolate from Defatted Jujube (Zizyphus lotus L.) Seeds

In this study, response surface methodology, based on Box-Behnken design, was used to optimize the extraction conditions of protein isolate from the defatted seeds of jujube (Zizyphus lotus L.). This research focused on the effect of extraction temperature (30–50&nbsp;°C), mixing time (15–75&nbsp;min), pH (6.0–10.0), and solvent to solid ratio (15:1–35:1 v/w) on the extraction yield of jujube seed (Z. lotus L.) protein. The pH, mixing time and extraction temperature were the most significant (p &lt; 0.01) factors affecting the yield of Z. lotus protein isolate. The optimum conditions were as follows: extraction temperature 41.79&nbsp;°C, mixing time 54.46&nbsp;min, pH 8.65, and solvent to solid ratio of 25.90:1. Under these conditions, the experimental percentage value was 81.52%, which is well in close agreement with the value predicted by the model (80.91%). The results of physicochemical analysis showed that protein isolate of Z. lotus ZLPI had most of the essential amino acids and hence could be considered as a high quality protein. Protein isolate from Z. lotus had a single denaturation temperature (120.17&nbsp;°C), while soy protein isolate had two denaturation temperatures (76.36 and 93.02&nbsp;°C). This fact is of great economic interest due to several applications of Z. lotus protein in the food pharmaceutical and cosmetic industries

Nutritional composition of Zizyphus lotus L. seeds

BACKGROUND: Zizyphus lotus seeds are an unutilized source of vegetable oil and protein and nothing has been reported on their physicochemical characteristics which would indicate the potential uses of these seeds. RESULTS: The percentage composition of the Zizyphus lotus seeds is (on a dry-weight basis): ash 1.05%, oil 32.92%, protein 19.11%, total carbohydrate 40.87% and moisture 6.05%. Calcium, potassium and magnesium constitute the major minerals of Zizyphus lotus seeds. The seed proteins are rich in threonine, glutamic acid, leucine, arginine and aspartic acid (26.73%, 17.28%, 13.11%, 9.47% and 7.76%, respectively). The main fatty acids of the oil are oleic (61.93%), linoleic (18.31%) and palmitic (9.14%) acids. Glycerol trioleate (OOO; O: oleic acid) was the most abundant triacylglycerol, representing 26.48% of the total triacyglycerols. beta-Tocopherolwas themajor tocopherol (130.47 mg100 g(-1)). This oilwas rich in Delta 7-campestrol and beta-sitosterol (147.82 and 82.10 mg 100 g(-1) oil), respectively. CONCLUSION: Zizyphus lotus seeds are rich in fat and protein which are of potential industrial significance. In addition, Zizyphus lotus L. seed oil contained many bioactive compounds. This fact is of great economic interest owing to several applications of Zizyphus lotus L. seeds in the food, cosmetics and medicinal industries

PHYSICOCHEMICAL CHARACTERISTICS AND ANTIOXIDANT ACTIVITIES OF ZIZYPHUS LOTUS L. SEED OIL

This study was designed to examine both the chemical composition as well as the antioxidant activities of the seed oil extracted from Zizyphus lotus L. The results showed that the neutral lipids were mainly composed of triacylglycerols (92.75% of total lipids). Phosphatidylcholine and digalactosyldiacylglycerol were the main phospholipid and glycolipid subclasses, respectively. Oleic, linoleic and palmitic acids were the major fatty acids in the lipids of Z. lotus seeds. In addition, b-tocopherol was the predominant tocol at 122.13 mg/100 g seed oil, which was equivalent to 60.41% of the total tocols followed by d-tocopherol (13.30%) and d-tocotrienol (8.95%). The total phenol and flavonoid contents were 18.45 mg/100 g and 2.31 QE/g oil, respectively, with ferulic acid as the main phenolic acid (1.36 mg/100 g oil). Overall, the strong antioxidant activities suggest that it could be advantageously used as a functional or nutraceutical food in order to prevent or moderate oxidative stress-related diseases

Exploring potential new galactomannan source of Retama reatam seeds for food, cosmetic and pharmaceuticals: Characterization and physical, emulsifying and antidiabetic properties

In this study, physicochemical, interfacial and emulsifying properties of Retama reatam and guar galactomannans were comparatively investigated. The results showed that Retama reatam galactomannan is mainly composed of total carbohydrates (95.52%) and lower protein contents (0.87%). The sugars identified were mannose (Man) and galactose (Gal), with a Man:Gal ratio of 1.85 compared to guar gum (1.83). The results of thermal properties indicated were transition temperature (T g ) and melting temperature (T m ) very similar to those of the guar gum. Moreover, results also revealed that there is no significant difference in terms of equilibrium interfacial tension of Retama reatam gum at 10 and 20 °C. Moreover, preliminary tests show that stable oil-in-water nanoemulsions may be formulated using Retama reatam gum. Therefore, measurement of mean oil droplet diameter d after heating at 80 °C, shows that stable nanoemulsions may be formulated using Retama reatam galactomannan. Further in vivo experiments confirmed that Retama reatam gum can reduce the glycemic index of starchy foods and inhibit the surge of postprandial blood glucose level