الفهرس 
General properties of microbial anylclytic enzymesOnly 14 pages are availabe for public view
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Abstract
SUt:I.:LTIY
Production of ~anylQse froTI the theroophilic
organisms h~s prccticcl cdvnntage in some technological
proceess, since the amylase of thermophilic organisms
has high stability against the high temperatures.
Therefore,the present investi8ntion wns subjected
to study the production of aramylase by thermophilic
organisTis ~~d to investigate factors affecting its
production ~~d functions.
Results obtained could be su~erized as follows:
in pure c-_•lturcs fro:;_ differen’~ so’lrces such as
compost, rhizosplcere, stc’ule wannure, dcugh, and air.
2- ’-11 these isol::ctes wert; screened c.ccording to
their a::-ylolytic activit:<_cs a””Jd co!:lpc.red with two
imported strains.
3- i~esul ts s’cowed ti~ct the loc.:ll is ole tes ’Jo. c}’
c5 and cl3 in additions to the two iwported
strains nanely :Bacillus ~:r:.o_the_E!!~.OY:flilus-117”).
115
NRRL und Bacillus stearotheroophilus-22 DSM were
the most active organisms in ruaylase production by
submerged culture.
4- The most active isolates were studied with respect
to their morphological, cultural and physimlogical
charact~ristics and identified as ~· stearothermophilus
according to Bergey’s manuel of detern~tive
bact erial ogy.
5- Studying the effect of different media by the most
active isolates on ~nnylnse production, it was
found that medium No. 4 Welker und Campbell
(contair.ir..g nutrient brCJth (Difco), 8 g; soditL-:J
ncetnte, 5.0 g; casein ~·drolyzcote, 1.0 g; K2H:Fc·4 ,
2. 5 g; llli2Po4 , 1.0 g; I~E~Cl, l.C g; lic.Cl, l.C’ g;
FeC13 . 6H2C, 5 :::Jg; l4;Cl2• 61’:2c, 5 wg; c.nd Cc.Cl2•
H2G, 5 ::1g) with B. stenrother::;ophilus-c5 gave t!:e
high~cst yLld of c(-:J.”Jylns.::. 7herefor.; :::;;,diw::. 1;o • .;.
production by ~· stearat~.::rmophilus-c 5 •
5- Testing the effect of the components of this medium
on tho:; production of c:C-nnylnse resu.l ts show thnt
nu.tri;:;nt broth, cr~sein hydrolyznte, NH4Cl, liaCl,
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MgC12.6H2o und FeC1 3 ~6:n2 o nt concentro.tions of 10 g,
1.0, 1.0, 1.0, 9 cg end 3 ng per liter gnve the
highest yield of ~enylcse while the presence of
sodiun o.cete.te, KH
2Po
4
, K2HPo
4
and CcC12 :U:.dno infJ;
luence on the ~anylcse production. Therefore in
the following studies these conponents were o~itted
7- Studyir.g th<- effect of different c=bon =d !:-sources
on G:.- s..’”:’v lc s co production by B. stearothe~ophilus-c 5
it wo.s ..,~.. OU!J.Q’ tho.t tryptone :ct the r2te of 0.2% r .\
end soluble sto.rcr. it c or.c en trc t i or. of 1.6% gave
the highest enz~e ~reduction.
tier. wcs st~iied to find c~t ~he opt~~=i ccr.dit~ons.
testt:.d ir.cul= siz”s C’-!”.d c.ge.
15.4 g; soluble ste.rch 16.0 g; :~ ::c Cl i. C g; 1ig CL .
.::
3 :e.g’ rc_·r liter
the opti~cl co;_di tic:: for enzyc., prc.::uctio:r.,
117 ”’
~cnyl~se of ~- st~~rothercophilus-c 5 was sepcrated
and purified.
10- Testing the incid~ce of intrccellular ~amylase
in B. ste~rothernophilus-c 5 it wcs foULd that
~-amylase of B. stearotheroophilus-c5 is a true
~xtracellular enzyoe.
11- Enzyme precipitation was carried out using different
conce~trationsof ethanol, acetone, isoprop~~ol and
=oniun sulfate. Results showed that 50% =oniu::J
sulfate followed by ccetone ct rctio of 1:3 (v/v)
gave the higl:est specific activity in enzyoe
;cr<Ccipitation.
12- _:,_ preli:-:-.ir.c..ry ex:;::~rine:-.t was :c:-.::ucted to c:l:.<cidcte
the pH v:::.lue o.t which r.igh p”rc<O:-,to.ge of the in”rt
.. _,hr_·i~t c.~~~-’-~ o~ +.~.. ~ 1··--··rt ”ret ir: ,.·-s -r-cl·~~+r•f• ~ ..... - -- ” - ’- !-’ -:::: ..... • .• ::;..:.. !”” c: .t-’ .L .. ·_: • - ·-
”t pE 5.0.
13- Fe::- <Or.zy::-.e puri:’ic~tic:-., the :c:2.lcwing schcn” was
c.C.cpted. Adjusting the liquor contair.ing er.zyr.1e
at pH 5.0 to precipitete th:= ir.,rt prot<Oin.
Fr<ec ipi tat ion by r~”ll::oniLU:: sulf~. te in 20%
118 -
concentration to rewove the residunl inert protein.
Applying 50% amoonium sulfate followed by acetone
at n ratio of 1:3 (v/v), then passing through
-.&.mberlite IRA-400 and finally reprecipitution by
acetone at ratio of 1:3 (v/v).
14- Regarding the specific action of ~uoylase of
B. stenrothermophilus-c5 , it was found that potato
starch was the best substrate as conpared with
rice starch and corn starch.
15- Gomparing the purified theruophilic ~amylase
with those from the ~esophilic bacteria and fungi,
results showed that:-
.A.- ’i’he opti::-,UJ::l tec.per~, ture for =ylase activity
were 6C, 50, e.::d .;.cac respectively.
E- Tne opti:·.:.m pE’ s fer ’=.:Jslase cc.ctivities were
6,6, :md 5 reS:tJectively.
C- The activitp of therQophilic bacterial ~ylase
was still stable at 5C, 60, a~j 70°C for 45
hrs., neantine activity of nesophilic bc.cterial
=Ylnse and fungal =ylase wer-2 still stable
at 5C°C for 4b and 6 hrs. respectively.
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.n’..d c’..l t.l on o f cn ++ io::s in c co~cc::tration of
C. Cl ;:.: i~cree:.sed t:1e -::ho::JOatc.bility of
D- Th~ ~ylolytic enzy.~es fro~ the 3 fore-nentioned
sources still str:.ble fer 48 r~s. e:.t p~ vr:.lues