22 research outputs found
Chemical Composition and Biological Activities of the Essential Oils from Three Melaleuca Species Grown in Tunisia
No full textThe chemical composition of the essential oils of Melaleuca armillaris Sm., Melaleuca styphelioides Sm. and Melaleuca acuminata F. Muell., collected in Tunisia, was studied by means of GC and GC-MS analysis. In all, 46 compounds were identified, 38 for M. armillaris, 20 for M. acuminata and eight for M. styphelioides, respectively. The presence of a sesquiterpenic fraction (52.2%) characterized the oil from M. armillaris;
M. sthypheliodes oil was rich in methyl eugenol, a phenolic compound (91.1%), while M. acuminata oil is mainly constituted by oxygenated monoterpenoids (95.6%). The essential oils were evaluated for their in vitro potentially phytotoxic activity against
germination and initial radicle growth of Raphanus sativus L., Lepidium sativum L., Sinapis arvensis L., Triticum durum L. and Phalaris canariensis L. seeds. The radicle elongation of five seeds was inhibited at the highest doses tested, while germination of all
seeds was not affected. Moreover, the essential oils showed low antimicrobial activity against eight selected microorganisms
Comparative study of two coniferous species ( Pinus pinaster Aiton and Cupressus sempervirens L. var. dupreziana [A. Camus] Silba) essential oils: chemical composition and biological activity
No full textMaritime pine ( Pinus pinaster Aiton) and Saharan cypress ( Cupressus
sempervirens L. var. dupreziana [A. Camus] Silba) are two
cone-bearing seed coniferous woody plants. The chemical composition of
their essential oils, isolated from needles and leaves by
hydrodistillation, was analyzed with gas chromatography (GC) and gas
chromatography mass spectrometry (GC/MS). A total of 66 and 28
compounds were identified, which represented 99.5% and 98.9% of total
pine and cypress oils, respectively. Pinus pinaster oil was found to be
rich in α-pinene (31.4%), (Z)-caryophyllene (28%), and
α-humulene (6.7%); it was characterized by relatively high amounts
of monoterpene and sesquiterpene hydrocarbons (44.5% and 46.3%,
respectively). The major components identified in cypress oil were
manoyl oxide (34.7%), α-pinene (31.8%), α-humulene (9%), and
6-3-carene (8.7%). Results of in vitro antifungal test assays showed
that both oils significantly inhibit the growth of 10 plant pathogenic
fungi. Herbicidal effects of the oils on seed germination, seed vigor,
and seedling growth of three common crop weeds Sinapis arvensis L.,
Phalaris paradoxa L., and Raphanus raphanistrum L. were also
determined; the oils completely inhibited seed germination and seedling
growth of all the weeds
Comparative study of two coniferous species ( Pinus pinaster Aiton and Cupressus sempervirens L. var. dupreziana [A. Camus] Silba) essential oils: chemical composition and biological activity
No full textMaritime pine ( Pinus pinaster Aiton) and Saharan cypress ( Cupressus
sempervirens L. var. dupreziana [A. Camus] Silba) are two
cone-bearing seed coniferous woody plants. The chemical composition of
their essential oils, isolated from needles and leaves by
hydrodistillation, was analyzed with gas chromatography (GC) and gas
chromatography mass spectrometry (GC/MS). A total of 66 and 28
compounds were identified, which represented 99.5% and 98.9% of total
pine and cypress oils, respectively. Pinus pinaster oil was found to be
rich in α-pinene (31.4%), (Z)-caryophyllene (28%), and
α-humulene (6.7%); it was characterized by relatively high amounts
of monoterpene and sesquiterpene hydrocarbons (44.5% and 46.3%,
respectively). The major components identified in cypress oil were
manoyl oxide (34.7%), α-pinene (31.8%), α-humulene (9%), and
6-3-carene (8.7%). Results of in vitro antifungal test assays showed
that both oils significantly inhibit the growth of 10 plant pathogenic
fungi. Herbicidal effects of the oils on seed germination, seed vigor,
and seedling growth of three common crop weeds Sinapis arvensis L.,
Phalaris paradoxa L., and Raphanus raphanistrum L. were also
determined; the oils completely inhibited seed germination and seedling
growth of all the weeds
Chemical Composition of Juniperus oxycedrus L. subsp macrocarpa Essential Oil and Study of Their Herbicidal Effects on Germination and Seedling Growth of Weeds
No full textApplication of differential evolution algorithm in transmission expansion planning
No full textTransmission expansion planning has become a complicated procedure more than it was. The rapid growth of the transmission networks and the deregulation has introduced more objectives and uncertainties to the transmission network planners. As a result of that, new approach and criteria that can replace the old ones are needed for TEP problem. The main goal of this process is to locate the additional transmission lines that must be added to meet the forecasted load in the system adequately with minimum cost. There have been several methods applied for this purpose; mathematical optimization methods, heuristic and Meta heuristic methods. This paper reviews the use of Meta heuristic method by the means of differential evolution algorithm (DEA) to solve this multi objective optimization problem. In addition, some suggestions have been made by the author that can make the DEA more efficient and applicable in the real world networks
Nutraceutical potentialities of Tunisian Argan oil based on its physicochemical properties and fatty acid content as assessed through Bayesian network analyses
No full textAbstract Background Argan oil is traditionally produced by cold pressing in South-western Morocco where rural population uses it as edible oil as well as for its therapeutic properties which give them in counterpart valuable income. Given the economical interest of this oil, several attempts of fraudulency have been registered in the world global market leading to loss of authenticity. Our purpose is to launch a program of Tunisian Argan oil valorization since trees from this species have been introduced sixty years ago in Tunisia. The first step was thus to characterize the physicochemical properties and determine the chemical composition of Tunisian Argan oil in order to assess its quality. Methods Physicochemical parameters of oil quality were determined according to the international standard protocols. Fatty acid content analysis of Argan oils was performed by gas chromatography coupled to mass spectrophotometry. A comparative study was realized among Tunisian, Moroccan and Algerian samples differing also by their extraction procedure. The impact of geographical localisation on the fatty acids composition was studied by statistical and modeling Bayesian analyses. Results Physicochemical parameters analysis showed interestingly that Tunisian Argan oil could be classified as extra virgin oil. Argan oil is mainly composed by unsaturated fatty acids (80%), mainly oleic and linoleic acid (linoleic acid was positively influenced by the geographical localization (r = 0.899, p = 0.038) and the P/S index (r = 0.987, p = 0.002)) followed by saturated fatty acids (20%) with other beneficial compounds from the unsaponifiable fraction like polyphenols and carotenoids. Together with fatty acid content, these minor components are likely to be responsible for its nutraceutical properties and beneficial effects. Conclusion Tunisian Argan oil displayed valuable qualitative parameters proving its competitiveness in comparison with Moroccan and Algerian oils, and could be therefore considered as extra virgin edible oil for nutraceutical purposes as well as for cosmetic use
Effects of the viroids and rootstocks on fruit yield and juice quality of Tunisian citrus variety “Maltese half-blood”
No full textNutraceutical potentialities of Tunisian Argan oil based on its physicochemical properties and fatty acid content as assessed through Bayesian network analyses
No full textTowards Include Preservation of Vitamins in Fenugreek and Carob Seeds by the Instant Controlled Pressure-Drop Process (DIC Process)
No full textViroid infection and rootstocks affect productivity and fruit quality of the Tunisian citrus cultivar Maltaise demi sanguine
No full textIn Tunisia, sweet orange citrus cultivars are usually grafted on sour orange rootstock. However, this rootstock is susceptible to Citrus tristeza virus (CTV). A trial was established in 2005 to evaluate the performance of newly introduced rootstocks compared to sour orange, using the sweet orange cultivar ‘Maltaise demi sanguine’ as the grafted scion. The effect of single or mixed viroid infections were monitored over 12 years. Once established, tree growth, cumulative yield, tree performance and fruit quality of ‘Maltaise sweet orange’ were assessed from 2008. Mixed viroid infections caused significant decreases (39 to 60%) in the canopy volume of ‘Maltaise’ grafted on Carrizo citrange, Swingle citrumelo, Cleopatra mandarin, Rangpur lime, Volkamer lemon and Trifoliate orange. The cumulative yield of trees grafted on’Alemow’ (Citrus macrophylla) and inoculated with Hop stunt viroid (HSVd) was 76% less than the healthy control. Mixed infections caused production decreases of 56% from trees grafted on Swingle citrumelo and 69% from those grafeted on Trifoliate orange. When quality parameters of fruit from trees infected with each viroid, and combinations of viroids were compared, no significant differences were recorded
