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Europaea L. (europaea + l)

Distribution by Scientific Domains
Chemistry50%
Life Sciences25%

Kinds of Europaea L.

  • olea europaea l.
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    Selected Abstracts

    Effect of convective solar drying on colour, total phenols and radical scavenging activity of olive leaves (Olea europaea L.)

    INTERNATIONAL JOURNAL OF FOOD SCIENCE & TECHNOLOGY, Issue 12 2009
    Neila Bahloul
    Summary In this study, olive leaves, which are known for their therapeutic and antioxidant properties, were used to assess the effect of solar drying conditions (temperature and flow rate) on the drying time and quality parameters of olive leaves. Samples were dried at three drying temperatures (40, 50 and 60 °C) and at two drying air flow rates (1.62 and 3.3 m3 min,1) in a convective laboratory solar dryer. From the experimental results, it was noted that the drying time required to reduce the moisture content to 0.10 kg kg,1 d.b. depends mainly on the drying temperature. The quality attributes of the dehydrated olive leaf samples were investigated in term of colour, total phenols and radical scavenging activity. The effect of solar drying on L*, a* b* parameters was significant (P < 0.05) for all the studied olive leaves. Besides, the total phenols of olive leaves were significantly (P < 0.05) influenced by drying air conditions and tended to decrease with increased drying time. The DPPH radical scavenging activity was higher in fresh [EC50 39.40 (ZR)-39.95 (CH)] than in dried leaves. However, the radical scavenging activity was also high in leaves dried at 60 °C, 3.3 m3 min,1 [EC50 54.21 (ZR),68.79 (CL)]. [source]

    ANTIBACTERIAL ACTIVITY AND CHEMICAL CONSTITUTIONS OF OLEA EUROPAEA L. LEAF EXTRACTS

    JOURNAL OF FOOD PROCESSING AND PRESERVATION, Issue 3 2010
    MIHRIBAN KORUKLUOGLU
    ABSTRACT The in vitro antimicrobial activity of aqueous, acetone, diethyl ether and ethyl alcohol extracts of olive leaves (Olea europaea L.) was studied. The aqueous extract of olive leaves had no antibacterial effect against the test microorganisms, whereas acetone extract showed inhibitory effect on Salmonella enteritidis, Bacillus cereus, Klebsiella pneumoniae, Escherichia coli, Enterococcus faecalis, Streptococcus thermophilus and Lactobacillus bulgaricus. Furthermore, the antimicrobial activities of some phenolic compounds against microorganisms were tested. The most effective compound was found to be oleuropein while syringic acid was found ineffective. The characterization of phenolic compounds in different extracts determined by high performance liquid chromatography-air pressure chemical ionization-mass spectrometry detector (HPLC-APCI-MSD GC-MS) gas chromatography-mass spectrometry (GC-MS). The acetone and the ethyl alcohol extracts had the most and the least oleuropein content, respectively. PRACTICAL APPLICATIONS In recent years the extracts of many plant species have become popular, and attempts to characterize their bioactive principles have gained speed for many pharmaceutical and food-processing applications. Especially, antimicrobial properties of plants have revived as a consequence of current problems associated with the use of chemical preservatives. Because of consumers' negative perspectives of synthetic preservatives, attention is shifting toward natural alternatives. The findings suggest that olive leaf extracts and their phenolic compounds have good potential as antibacterial substances in food preservation as they may be more acceptable to consumers and the regulatory agencies in comparison with synthetic chemical compounds. [source]

    Erratum: The effects of a seaweed extract in addition to nitrogen and boron fertilization on productivity, fruit maturation, leaf nutritional status and oil quality of the olive (Olea europaea L.) cultivar Koroneiki.

    JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 7 2009
    Christos Chatzissavvidis, Eleftheria Tsabolatidou., Ioannis Therios, Maria Tasioula, Vassilios Chouliaras
    The original article to which this Erratum refers was published in Journal of the Science of Food and Agriculture 2009: 89: 984,988 [source]

    Genetic and chemical assessment of Arbequina olive cultivar grown in Córdoba province, Argentina

    JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 3 2009
    Mariela M Torres
    Abstract BACKGROUND: Thirty-eight accessions of olive (Olea europaea L.) originating from Córdoba province (Argentina) and preliminarily identified as belonging to the Arbequina variety were genotyped using AFLP (amplified fragment length polymorphism) DNA markers. Also, the oil chemical composition was studied during three consecutive crop years. The objectives of the work were (a) to investigate genetic intra-cultivar diversity and (b) to evaluate the oil chemical composition and compare it with that of Arbequina oil produced in Spain. RESULTS: The 19 primer combinations employed to perform the AFLP analysis produced 98 polymorphic bands. A reduced genetic heterogeneity was obtained, confirming that (a) the selected accessions belong to the Arbequina variety and (b) the traditional vegetative propagation practice has caused low genetic erosion in this variety cultivated in Córdoba. The main features that characterise the Argentinian Arbequina oils studied are the lower content of oleic acid and higher levels of phenolics and high-molecular-weight volatile compounds compared with those found in Spanish Arbequina oils. CONCLUSION: In spite of the small proportion of intra-cultivar variability, the Arbequina variety grown in Argentina produces oils with different chemical traits from those obtained in the original Spanish growing region. These differences can be attributed mainly to the particular environmental conditions of the olive-growing areas in these countries. Copyright © 2008 Society of Chemical Industry [source]

    The colonization history of Olea europaea L. in Macaronesia based on internal transcribed spacer 1 (ITS-1) sequences, randomly amplified polymorphic DNAs (RAPD), and intersimple sequence repeats (ISSR)

    MOLECULAR ECOLOGY, Issue 7 2000
    J. Hess
    Abstract Phylogenetic relationships in the Olea europaea complex and the phylogeography of 24 populations of the Macaronesian olive (O. europaea ssp. cerasiformis) were assessed by using three molecular markers: nuclear ribosomal internal transcribed spacer 1 (ITS-1) sequences, randomly amplified polymorphic DNAs (RAPD), and intersimple sequence repeats (ISSR). Parsimony analysis of the ITS-1 sequences and Neighbour-joining (NJ) analyses of RAPD and ISSR banding variation revealed four major lineages in the O. europaea complex: (1) ssp. cuspidata; (2) ssp. cerasiformis from Madeira; (3) ssp. laperrinei; and (4) ssp. cerasiformis from the Canary Islands plus ssp. europaea. These results provide unequivocal support for two independent dispersal events of Olea to the Madeira and Canary Islands. Molecular and morphological evidence led to recognition of two separate olive taxa in Macaronesia, to date included in ssp. cerasiformis. NJ analyses of the combined RAPD and ISSR data suggest that the colonization of the Canaries by O. europaea may have followed an east to west stepping-stone model. An interisland dispersal sequence can be recognized, starting from the continent to Fuerteventura, Gran Canaria, Tenerife, La Gomera, and finally La Palma. High dispersal activity of the lipid-rich Olea fruits by birds in the Mediterranean region is congruent with multiple dispersal of olives to Macaronesia and successive colonization of the archipelagos. The observation of strong genetic isolation between populations of different islands of the Canary Islands suggests, however, that subsequent interisland dispersal and establishment has been very rare or may not have occurred at all. [source]

    Isolation and characterization of polymorphic microsatellites in olive (Olea europaea L.) and their transferability to other genera in the Oleaceae

    MOLECULAR ECOLOGY RESOURCES, Issue 3 2002
    R. De La Rosa
    Abstract Seven polymorphic microsatellites were developed in olive. Six of them came from a genomic library enriched for GA and CA repeat sequences. They showed single locus polymorphism in a set of 23 olive cultivars (from six to nine alleles per locus). Three different pairs of loci were sufficient to discriminate all cultivars. The other polymorphic primer pair was designed from a published sequence for olive lupeol sgutase and revealed just two alleles. The seven primer pairs were tested on two accessions of five other species of the Oleaceae and three, EMO2, EMO13 and EMO90, revealed polymorphism in two, four and three species, respectively. [source]

    Use of antimicrobial methylcellulose films to control Staphylococcus aureus during storage of Kasar cheese

    PACKAGING TECHNOLOGY AND SCIENCE, Issue 8 2009
    Belgizar Ayana
    Abstract Olive leaf extract (OLE) (Olea europaea L.) is a natural product that has antimicrobial effect on many food pathogens. In this study, methylcellulose (MC) based antimicrobial films containing 0.5,3% (w/v) OLE and glycerol (1.6%, v/v) were produced. The effects of OLE amount on the water vapour permeability (WVP), mechanical and antimicrobial properties of the films were investigated. The films were effective against Staphylococcus aureus (ATCC 25923). The OLE in the film solution caused a decrease in WVP and elongation (E), and an increase in tensile strength (TS). The MC films containing 1.5% (w/v) OLE were applied on Kasar cheese slices inoculated with S. aureus. The count of S. aureus decreased 0.68 and 1.22,log cycle at the 7th and 14th days, respectively. Copyright © 2009 John Wiley & Sons, Ltd. [source]

    Food supplementation with an olive (Olea europaea L.) leaf extract reduces blood pressure in borderline hypertensive monozygotic twins

    PHYTOTHERAPY RESEARCH, Issue 9 2008
    Tania Perrinjaquet-Moccetti
    Abstract Hypertension is a harmful disease factor that develops unnoticed over time. The treatment of hypertension is aimed at an early diagnosis followed by adequate lifestyle changes rather than pharmacological treatment. The olive leaf extract EFLAź943, having antihypertensive actions in rats, was tested as a food supplement in an open study including 40 borderline hypertensive monozygotic twins. Twins of each pair were assigned to different groups receiving 500 or 1000 mg/day EFLAź943 for 8 weeks, or advice on a favourable lifestyle. Body weight, heart rate, blood pressure, glucose and lipids were measured fortnightly. Blood pressure changed significantly within pairs, depending on the dose, with mean systolic differences of ,6 mmHg (500 mg vs control) and ,13 mmHg (1000 vs 500 mg), and diastolic differences of ,5 mmHg. After 8 weeks, mean blood pressure remained unchanged from baseline in controls (systolic/diastolic: 133 ± 5/77 ± 6 vs 135 ± 11/80 ± 7 mmHg) and the low-dose group (136 ± 7/77 ± 7 vs 133 ± 10/76 ± 7), but had significantly decreased for the high dose group (137 ± 10/80 ± 10 vs 126 ± 9/76 ± 6). Cholesterol levels decreased for all treatments with significant dose-dependent within-pair differences for LDL-cholesterol. None of the other parameters showed significant changes or consistent trends. Concluding, the study confirmed the antihypertensive and cholesterol-lowering action of EFLAź943 in humans. Copyright © 2008 John Wiley & Sons, Ltd. [source]