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EFFECT OF MICROWAVE POWER ON QUALITY PARAMETERS OF PECTIN EXTRACTED FROM MANGO PEEL
2007
M Assous | E Abd El-Wahab | K El-Waseif
The present study aims to use microwave pow-er to facilitate the extraction of pectin from dried mango peels, and also to explore the effect of power on some quality parameters of the resultant pectin. Chemical composition of dried mango peels ascertained a high percent of total pectin, being 16.01 % (on dry weight basis). With respect to microwave heating, the optimal experimented power was 600W, and 6 minutes as the best short holding time, which gave 12.80 % yield, 86.54% recovery and 77.20% anhydrogalacturonic acid (AGA) of extracted pectin. Comparing to the commercial pectin, the results of some physico–chemical characterstics of isolated pectin, revealed that the pectin isolated by microwave heating from mango peels, being to some extent analogous to the commercial pectin with respect to its qualities, such as high methoxyl pectin, high degree of estri-fication (DE), and high percent of AGA besides its high viscosity, followed by the pectin isolated using the conventional method. Statistical analysis of organoleptic data showed no significant differ-ences between strawberry jam prepared by using commercial pectin and that treated with pectin isolated by microwave heating as affecting their texture, color, taste and preference. Besides, high significant differences were detected between var-ious concentrations of added pectin, with respect to the texture alone. Generally, the utilization of pectin isolated from mango peels using microwave heating in jam processing gave high quality attrib-utes resembling that of the commercial pectin when added to strawberry jam and this would also lead to gain economical benefits.
Mostrar más [+] Menos [-]BIOCHEMICAL AND MOLECULAR CHARACTERIZATION OF SOME YEAST ISOLATES
2007
A. Abulhamd | M Mokhtar | Rasha Farrag,
Sixteen yeast isolates from various sources in-cluding molasses, foodstuffs, concentrated juices and soils were identified using simplified API 20 C AUX yeast identification system and random amplified polymorphic DNA-polymerase chain reaction (RAPD-PCR). The isolates were found to belong to 11 species; Candida famata, C. glabra-ta, C. krusei / inconspicua, C. norvegensis, C. col-liculosa, Cryptococcus humicolus, Rhodotorula mucilaginosa, Kloeckera spp., Geotrichum capita-tum and Saccharomyces cerevisiae. API and RAPD-PCR proved to be useful and convenient taxonomic tools for rapid identification at the spe-cies level, proving that at least two techniques are needed for precise identification. RAPD-PCR pro-cedure is faster than traditional characterization techniques; the identification of a single colony was typically achieved in less than 10 hr.
Mostrar más [+] Menos [-]AN ECONOMIC STUDY OF OLIVE CROP IN EGYPT
2007
A Abd Almksod | Abeer Kinawy | H.E Seddik
Despite of the great healthy advantages of ol-ive crop whereas it protects human from arterio-sclerosis, heart diseases and blood cycle diseases, the interest of the Egyptian consumer to buy and use it is weak, except in its production regions. This is, because the Egyptian consumer is not used to it and because of its high prices which vary from L.E 12 to 18 per kilogram for the good varie-ties and from L.E 20 to 30 per kilogram for excel-lent varieties, and in the shadow of the decrease in the produced amounts from cotton seed oil due to the recent decrease in cotton production and there is no main source in enough degree to depend on, to restrict our imports from oil in general and from olive oil in particular. The problem of research is restricted in recognizing the nature of olive crop market in Egypt and also the status quo of food gap from it, and out of this standpoint, the re-search aimed at analyzing the current structure of production and consumption of olive crop and olive oil and also the structure of its foreign trade along with shading a light on the relative ad-vantages of this crop, and the competitive situation of the Egyptian olive in the international market. And for achieving research aims, the inductive method was depended on, in the economic analy-sis and also econometric methods were used, also the scientific references and obtaining the neces-sary data of analysis from different resources dur-ing the period (1991–2004) were depended on. The analysis results showed that there is a signifi-cant increase in evolution of total area, production area, productivity, and production of olive during study period. In regard to the most important gov-ernorates in olive production, it is shown that Fay-oum governorate occupied the first grade in re-garding cultivated area followed by Matrouh, North Sinai, Nobaria, Ismaelia and Cairo respec-tively during 2004, while Matrouh governorate occupied the first grade in regarding production area and followed by Fayoum, Nobaria, North Sinai, Giza and Ismaelia respectively, but from the productivity respect, El Behira occupied the first grade and followed by Bennisweef, Giza and Monofia respectively. And by studying some indi-cators of food gap of olive and olive oil in Egypt, it is shown from analysis that there is a significant increase in evolution of oil consumption and the increasing rate of the annual consumption is slightly equals its counterpart related to production evolution, i.e. more than 95% of national produc-tion is directed basically to consumption. In regard to studying some foreign trade indicators of olive crop and olive oil in Egypt during the period (1990 – 2004), it is shown from analysis that there is an oscillation in the amount and value of olive oil exports up and down during the first and sec-ond stages of the study and this appears from the suitability of the cubic figure to express the evolu-tion of both. By studying average export price of olive oil, it is shown that there was a statistical significant decrease during the study period. As for the import price, there was an oscillation along
Mostrar más [+] Menos [-]MONITORING THE EFFECT OF SOME INSECTICIDES FOR CORN STEM BORER CONTROL, AT DEIR EZ-ZOR REGION, SYRIA
2007
M Idraw | E. Al-Jouri
The corn stem borers larvae (species Sesamia cretica Led., Sesamia nonagrioides Lef. and Os-trinia nubilalis (Hübner)) are considered the major pests attacking Zea mays L. The larvae bore into stems and ears which cause a significant decrease of both quantity and quality of yield. This research was completed at Eastern region of Syria during 2004 and 2005 corn growing season, aiming to control these corn borer species with some insec-ticides; Avaunt 150SC (Indoxacarb 150 g / L),Sumialpha 5EC (Esfenvalerate 50 g / L), Proclaim 05SG (Emamectin benzoate 50 g / Kg), Comply 25WP (Fenoxycarb 205 g / Kg) and Agerin 6.5WP (Bacillus thuringiensis kurstaki 32000 IU / Mg). The results showed that in corn attacked by Sesa-mia cretica, Sesamia nonagrioides and Ostrinia nubilalis the infested rate reached up to 38 % on stems and 18.5 % on ears at control plots. Results also showed high efficacy of insecticides Avaunt 150SC, Sumialpha 5EC, Proclaim 05SG, Comply 25WP and Agerin 6.5WP in reducing the infested rate in stems to about 6, 8.1, 11.5, 13.5 and 21.2 %, respectively. And to about 4.5, 6.1, 7.2, 7.9 and 11.1 % in ears by Avaunt 150SC, Sumialpha 5EC, Proclaim 05SG, Comply 25WP and Agerin 6.5WP, respectively. These results gave rise to a positive increase in the yield of corn seeds.
Mostrar más [+] Menos [-]INDUCTION OF RESIISTANCE IN TOMATO PLANTS AGAINST ROOT-KNOT NEMATODE BY SOME CHEMICAL AND PLANTS EXTRACTS(a)
2007
Mostafa M | E Gado | M Youssef
Different agents were tested as inducing re-sistance factors in tomato plants against root-knot nematode Meloidogyne incognita. These agents include ethyl salicylic acid, (0.125 ml/l) jassmonic acid (0.125 ml/L) sincocin solution, (0.1%) agrispon solution (0.1%) water extract of mango malformed inflorescence (7.5%), coconut milk solution (2%) as root dipping during transplanting and spraying after one month from transplanting. Data obtained clearly indicated that sincocin solu-tion, extract of mango malformed inflorescence, agrispon solution and jassmonic acid led to a great reduction in disease severity, number of galls/ root, number of females/ root and number of egg masses/ root, followed by ethyl salicylic acid and coconut milk descending order. All tested agents did not affect juvenile's viability except mango malformed inflorescence extract and coco-nut milk solution which led to slight effect on juvenile viability. All tested agents increased plant growth in the presence of nematode inocula in comparison to untreated plants. In this respect coconut milk solution had the superior effect. Data indicated that the tested agents induced resistance in treated plant and the mechanisms of their mode of action needs further studies.
Mostrar más [+] Menos [-]PRODUCTION OF MICROBIAL CELLULOSE BY TEA FUNGUS "KOMBUCHA"
2007
Sheh ata | Sawsan F | Hussein Ali
In seeking economic production of microbial cellulose, the available and low cost commercial kombucha starter, contains mainly Acetobacter xylinum and Saccharomyces sp., were used under static condition. The best medium composition was black tea extract (1.0 g /100 ml H2O), sucrose (20%) and corn steep liquor, CSL (1%) at 26-28oC for 10 days. The cellulose yield (1.3 g /100 ml) and productive rate (1.3 X 10-3 g / day /ml) were higher than some reported values. Addition of folic acid or its building block p-aminobenzoic acid at additive concentrations 0.20% led to dou-bling the yield (2.37 and 2.43 g / 100 ml culture respectively) and the productive rate (2.37 X 10-3 and 2.43 X 10-3 g / day / ml respectively). Scan-ning electron micrograph showed the structure of the produced microbial cellulose fibrils without any microbial flora after treatment with 1% NaOH.
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