Carotenoids were separated from the wild type yeast
R.mucilaginosa (A23) and its UV mutant at (254 nm)
R.mucilaginosa (A23-M) using thin layer chromatography
(TLC).The results showed the wild type yeast gave three color
patches, β-Carotene,Torule
ne and Torularhodin with Rf values of
0.9, 0.7 and 0.2 respectively, while the mutant yeast gave only one
spot of color ofTorularhodin at thethe value of Rf = 0.2. Carotenoid
produced by mutant yeast R.mucilaginosa (A23-M) was purified
using a column stocked with polychlorinated Hyflo Super Cel and
magnesium oxide with a ratio of (1: 2). The purified carotenoid was
analyzed by high performance liquid technology chromatography
HPLC at a wavelength 495 nm showing that there was only one
colored compound which was Torularhodin
Four strains of lactic acid bacteria (LAB) from different genus، species and
sources were tested for their abilities to bind of AFM1 for 14 hours.
Lactobacillus rhamnosus LC705 showed higher ability to bind AFM1 (88.35%)،
followed by Bifidobacteri
um bifidum BG1 (84.21%), Lactobacillus bulgaricus
R21 by 80.41% and finally Streptococcus thermophilus by 71.52% after 14
hours of incubation.
Rhodotorula yeast was isolated from various local sources. Fifty isolates
were collected during the years 2012-2013 where 13 were isolated from soil, 23
from tree leaves and 14 from food. The isolates AUX system. Were classified
into three Rhodoto
rula species: R. mucilaginosa, R. glutinis and R. minuta with
76%, 20% and 4% respectively using API 20c. Six methods were applied in
breaking down the yeast cells and extracting the carotenoids. It was shown the
quantity of carotenoides extracted with the modified method by adding DMSO
to the yeast biomass and incubating for 24 hrs at 4˚C yielded in higher
quantities when compared with the other five methods. All isolates were able to
produce carotenoides but they varied in their efficiency where the isolate A24
(R.mucilaginosa) isolated from food was distinguished by its high level of
production which reached 658.23 μg/g dry weight compared with the others.
Ninety-nine randomized samples of milk and white cheeses were collected
from five districts in Damascus city during 2012-2013 to determinef Aflatoxin
M1 using High Performance Liquid Chromatography (HPLC). The procedure
for determination of Aflato
xin M1 was changed according to local
circumnutates which gave sensitive and accurate results during 5.9 minute with
r= 0.99. The average recovery was 83.88% for milk and 102.15% for cheeses
samples, respectively.
45 samples were collected from various sources (soil, degraded wood and
mushroom compost) from three cities (Damascus, Homs and Lattakia). 18
Trichoderma isolates were isolated and identified by microscope. These isolates
were screened using CMC m
edium with Congo red dy to identify their ability
to produce cellulase complex. The amount of enzyme production was
determined depending on the radius of clear zone around the colony. Results
showed that the most productive isolate was Tr with radius 7 ± 0.2 cm followed
by Tg and Ti. Optimization of cellulase production was performed using
response surface methodology (RSM). The optimal parameters were:
temperature 29.5 ˚C, pH = 6، incubation time 4 days, aeration speed 175 rpm
and wheat straw concentration 3%. All studied parameters had significant
effect on cellulase enzyme activity.
Thirty randomized samples of sugar materials were collected from different
places (Tartous, Damascus, Homs) in Syria for isolation and identification of
some yeasts. These yeasts were classified physiologically by API technique
to identify the spe
cies of Yeasts found in these materials. Results showed that
the isolated materials contained 17 isolated yeasts distributed in 3 genus and 7
species and named as follows: One isolated yeast from Geotrichum capitatum,
Candida krusei,Candida guilliermondi, Candida fumata and Candida zeylanoides
and 4 isolated yeasts from Candida lusitaniae and 7 isolated yeasts from
Saccharomyces cerevisiae. The classified yeasts were screened to investigate the
activity of internal and external invertase produced by them using
spectrophotometer at 540 nm. The results showed that there were differences in
the ability of yeasts to produce invertase enzyme. Candida Lusitaniae-2 and
Saccharomyces cerevisiae-4 were found the best yeasts for production of
external invertase, whereas Candida Lusitaniae1 was the best for internal
invertase.
The effects of Syrian wheat class and locally produced flour types on the
rheological properties of instant noodles production were investigated. Two
wheat classes (soft and durum) and two varieties of each were selected. These
varieties were mill
ed into standard flour (80% extraction rate) and high quality
flour (72% extraction rate). Dough rheological properties were evaluated by
farinograph and extensogarph techniques. Noodles cooking properties were
measured according to the AACC approved methods. The rheological
characteristics and the statistic analysis revealed significant differences among
the selected varieties, and reflected directly and significantly on the cooking
properties of the resultant noodles samples. This indicated the possibility of
using farinograph and extensogarph techniques in predicting the quality of the
resulting noodles. Furthermore, F test and distribution of variance analysis
showed that wheat class was of a vital and significant effect on dough
rheological properties and noodles quality comparing by wheat variety and
flour type.
Twenty two samples of black tea were collected from local Syrian markets
during 2009-2010 to study the quality characteristics of tea in terms of
moisture، water extract، caffeine، total ash، water soluble ash، alkalinity of
soluble ash, insoluble
ash in diluted hydrochloric acid in addition to
microscopic examination.
Results showed that all tested samples were identical to the Syrian Standard
No. 286/2003 for all above quality specifications، except for caffeine percent
which was less than the standard in 4 samples. The results also showed that
there was no adulteration with foreign plants nor exhausted tea leaves.
This research aimed to study the effect of various growth conditions
(temperature, culture age and culture medium) on the fatty acids composition
of cytoplasm membrane of 37 isolates of Staphylococcus aureus using Gas
Chromatography-Mass Spectrome
try (GC-MS). Results revealed that the total
number of fatty acids of Staph. aureus was 33. Eight of them were principle and
included: anti-isotetradecanoic acid (aC15:0), octadecanoic acid (C18:0),
eicosanoic acid (C20:0), isotetradecanoic acid (Ci14:0), isotridecanoic acid
(Ci15:0), hexadecanoic acid (C16:0), antisohexa- decanoic acid (Ca17:0) and
octadecenoic acid (C18:1) with a percentage of 33.96, 18.37, 14.94, 7.32, 6.23,
4.14, 3.03 and 2.89%, respectively. The percentage of each of the other fatty
acids was less than 1%. Increasing the incubation temperature was associated
with reducing the percentages of Ca15:0, Ci15:0, C16:0 and C18:1; and
increasing Ca17:0, Ci14:0, C18:0 and C20:0. The increase in incubation period
caused a decrease in C16:0, C18:0, C18:1 and C20:0; and an increase in Ca15:0
and Ca17:0. Moreover, the variation in culture media caused differences in the
percent of Ca15:0, C18:0 and C20:0; while the other fatty acids showed no
changes.
Four varieties of grape raisins where made in traditional way and
investigated for their chemical composition, mineral elements and total
antioxidanst capacity. Results reveals that there were significant differences in
the average percentage of m
oisture and carbohydrate between varieties,
whereas the protein, fat and ashes percentages were not significant. Results of
minerals analysis showed that blue raisins had the highest amount of Calcium,
phosphorous and potassium with a level of 66 mg, 193 mg and 989 mg in 100 g
raisins respectively. In addition, the total polyphenol contents by Folin-
Ciocalteau assay were higher in blue (257 mg) and red raisins (213mg) when
compared to the others varieties and vitamin C was 45mg/100g and 34 mg/100g
in blue and red raisins respectively. The antioxidant activity of raisins was
assessed by the 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging assay.
The amount of raisins needed to scavenge 50% of DPPH radical (EC50) was
similar for all varieties ranging from about 4.18 mg to 6.41 mg. Total
antioxidants capacity were in descending order blue >red > white > green
raisins. Therefore, the consumption of raisins is considered to contribute the
intake of antioxidants and minerals in Syrian diet .
