الفهرس 
Factors effecting amino acids content of yeast scpOnly 14 pages are availabe for public view
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Abstract
In this i,•estigatirr
li ty single cell p:::.”otein ( :. ) . Those cultures w;::re
thus, screened according tcJ tLeir yield 9 yield coefficient,
protein, total carbohydr&tes, ,;lucan, mannan and
amino acids content. Propagation of these cultures
1NHS carried on moL:.sses mediwn as a sui table cheap
rsvv material for ycc’ast propagation.
It was fo1F~d that t!!ece straL1s vary consider·-
ably in their rate of gro~th and different parameters
,~,f the ~uality of their :;cp. It was also fou~d tnat
strains belonGing to S.cerevisiae were the j’Yjost active
The i ’lVe stigated cul htres werr; also fonnd ”to
show consider.J,ble ;:ifferences in cru’~f’ prDtein conte.
nt, \Jitn r;b: highest levels .Ll: ’.:me ~:Otrrin~ ur
cerevisiae.
in iif:’ r’-~nt cultures. .E. e()tl..-cystine figures.
Acco rdinc:: to the s.bo ve study three cultures,
which showed, the highest yield, lo·,vest glucan and
mannan, and the highest metl:ionine, cystine and lysine
were selected for further studies. The selected cul-
562) and C .yui.J.::j.s (CBS 397), These cultures were exposed
to N-nitronitrosoquanidine as a potent chemic2l
mutagen, and the produced t=1.~J.xctrophic mutR.:-::tE; were
picked. This study sho~ed that the number f survivals
decreased as the time nf expos1.cre to the mutagen
increased. The percentage of auxctrophi:: mutants to
the total survivals increased with 1ncrease of the expo
sure to the chemical rn’;t ,<’ro::n t!J’ YHJ. tag en ic
tre8.tmi:>nt a larfc~C c :J lle ctiu, f aux- tra ph:L,:; : :u tR.r+:;:;
v;ere picked. These includr:· ~·~ mut 11ts L·cJr:; ~.,cerevisiae
~.ts from c.utilis
,· ~- c~
~ ... .:_~) ”-:.’ r) \
L ·
~on with thei:•” pan: t cult;
The select::d tr,rcl’ btc’St ’lluta .Js and ibt:ir par--
ents were used to .study the effect of enviromnental
factors on their yield and different criteria of the
quality of their SC?. It was found from this study
that the sugar concentration in the propagation medium
hds a clear effect on the yield and quality of the
pi!!oduct. The highest yield for the three mut’ nt and
their original cultures was at Ji) sug:::cr concc’ tration.
T{le total c~:trbohydrates, T<annar:c and glucan
content was incre&sed by increhsing t’ ~ sugar rJncentration
for all tho tested str~ins.
clear difference between p~rental cultures and their
u_ tant s were Lower than par<” nt~-”1 cul tt;res in Pli_L’1nan
and ,c;::lucan Cclltent-~
that -.. J_l ,!Ulst s i_ .r·.=ti:ts t__lti_lizcd rrnJ.tar.. . ts.
gen source f()r C.albicans and its m~~ants.
Nitrogen source had no effect on total carb8-
hydra tc, mannan a.::1d glucan in the mutants and their
original culture:=:;.
pli value of the e;:co·/:th me diu:\ was ,:tlsn found
to affect the gro th of the studied yeast cultures.
mutants was at p, - 3.5. ~Vl1i~e for c.albicans and its
’,, ---- - -~-~””
mutants was at pi’l 5.5. t1ll carbohydrate, :;lannan
and glucan follo d tho f:.;<c,me trend. Thei:r level generally
increased ~ith th~ increase in pH. The lowest
total c:trbohy rate, TLLannnn and glucan \V’’lS at pH
J. 5. f’Jr all the three .strairw e”nd t:1eir muta~-cts.
VIhilc
.utilis ·u1•’i i+;s muti:mt. ’L’hc grov. t
el i’c c+; r: -,tal
ERn ancl glucan i1 slowed
by ’:c: mut nt
by the lowest man~~n and Glucan cnnte, t.