Post on 21-Apr-2021
A ITU>Y OP 1111 IF'FICT OJ' DJLVl'IOlf IATI 81' IMCT.DJAL POPVLATI019
., •••• ... ••• 11 •••••••
Tll•••• •••• , •••• , •••• o ••••••• '•••ltJ ••••• Vtratata Pol1t••••t• l••tit•t• ,. • ••• , ••• , ••• ••• •••••• •f
llAITD OJ' ICJDCI
ill ... ,, .. , ... , ...... .
••••••• 1•••
1.
ll.
Ill. u.
'· n.
Vil,
nn. u. x.
XI.
Ul.
·2·
•••• IftlODUCTIOH··-···-·················--·-··-· 3 llYIIW or LlftMTUIB············-··········• S
OBJICT-·----------------------------------·- 14 HITHODI AID MlTllJALI····----···-·-········-15
lllULTS•···-·--·--·-······--·--·-·-··-··•••• 29 DlSCUSSlOll•••··--·······-··--·------·----··· 38
lllftlt.USlORS··--·-···--·-·-······----·--·-·•• 42 SUllfll.Y··························------··••• 43 A~•·•••••••••••••••••••••••••• 45
UTA···--··-········-····-···-······-·--···· 46 IDLlOG-IAftY••····--··-····-··-·-··--·-····• 47
APRllD11BS··---------·--------·-------------49 Appa4:1.x A • Theory of the Coulter
Couater·······-·------·-··•· 49
Appeadix I • Cleaalag of Clae1Var .. -·-··· 53
ImROOUCTION
y ~roblems in sanitary en~1nooring require
tau•l•d1e of the growth dyna•lcs of microbial ftF•t•~$.
for ez••Pl~, ourrently, •est reaearcb on blcl•glcal
wa~t• t~•ata•nt is b&$ed on ht empirical approache~.
Eluc1d~tien ~t tb• t~ndamental biol~~Y is neCG$~a~y
before a meanS••fal approaeb fa~ i•praw1n1 o••plex
biological proo••••• can be tor•ulated. A knowledge
culture
ot populat ton dyruu111hu11 in such iu1vircu11\l$t1iiil a~ streams,
sewage treatment facllttl••• and water tr•at•ent
t~cili U.t11s can b$ i<•ached. .Mixed cultures studitu! by
batcb t~chalquea tend to give re$ult• whlcb are
dlfflcult to tnte•p•et beoau5e •f almulta~eoue ehan1••
, nutrient
oonce~tr~tion, waste p~oduot accumulation, m~tabolie
int~rmediat~ pool•, and the lik•. Contin~ou~ flow
praeedure• t•nd to ••tabll•b steady-state• wblcb bold
constant sue~ envi~onmental faot~r$ a~ ~ut~ient
ccncentratien, averag• physiological ace, and phys!o-
cb•mical condition•.
At fi~•d nutrient co~centration and dilution
~ate not •xoeeding the maxi~um growth r•te, a pure
culture will In theory •~aob a •t•ady•8tate population.
Wiuim the iii ion rat• h~ si;reater than th• grow th rate
of tb• organlsa. wa6h•aat should eccar. In a rand••
atsed cultura, dilution rate sbaul• ha•• the eam~
lnteractin1. ••1antsas with slower 1rawth rat•&
•hould be waab~d t•om the srowth wea••l befo•• tboae
t AU~b•r of sp•c1eG of or~ani$m$ ~hould th••• d•Or@a&~ with only-• more hardy and faster •rowln1
orgaaS~M• ••~alnlng.
thl~ ••~earcb tbe Gffect• of dilution rate
on population we~e studiee for a pu~~ culture of ~.1..c.J..llu~
·H~~e:gs~, a mix•d cultur• of Bscillus e.it,JNtU. •UUl 11\•roba,ete,r
~·¥-:~g1ntt§, and 11 complet•lY ra.a:uhu1 mi~~Hi cn1li.:.t.t1<•. The
object$ of thl~ atud' •~••: 1) to det•rmln~ whether
e·t~uuty-stattt popi1lat:lcru1 a1'• ?'eaohed in gnn·• o•nt:hlueiusi
flo• cultures of •noap•alated organism• saoh as Baolllas
Qt•111, 2) to compare tbe•e reGult$ to tha centlnaeus
flow theory, 3) ta deter•lne tbe effect or di tion rate
upen population Of the defined aixed CUltur• 1 1 a•••¥! and A1 •!••«•nasA and, 4) te deter•lne th• eff•ct• of
dilution •at• upon a randoa ~ixed eu1ture.
ba«te•la la eoatiaueas ••ltu••· The ••$eat
thl~ ol•••I06l aaalJ•I• ol tb~ •••ti••••• l• that aic•••l&l a•••th I• thl$ s1•••• aoble••• a
•
lat• a oompletely •ia•d 1rowth •••••I •••'al•l•1 a
p~u·• eult1:n••• Bue~ •u:•vit-n~••nt~l fact~Ya; •uo.h -.s
coruh\Htt•atto~ of nutf'tent• 1 Mt&bollc pl'odtu~'h~ -.~ul
Cans ith~r b&Ot•rlA 1.-•wlng itt 11n1eb a c~ttt
oultur•. the laflQWiftt: mfluUa @ent.ai:n.i ~ $:ht
l:h1!ttn1 «n•1a.~ie llntbetrate at • CUUlOflUttl.-atton s1 • It
a.~d •~Yl•Hl flupply is alw.,y~ ~.uSeqvatu~ i Uu; $~f>p1:;
*t o~gani .. e l!uhstra'fa» t~ 'h•r•:foa-• tile l!!lOl• ~:a"OW"tb•
1 i h~r fact°'.-. Tae Y4Ut1a..,le• of iat!ll'thtt iu•e 1uut
s~b!\ltratfi 0~11cu1:n.tl"&thu1 and th$ di1utio~ ~ei.te. A
of tb.fHH' eat'h"OlUHnttal faot(lra. •.aa affect 1rowtb rat•
an4 cencentration ~f o~ganisn$.
... t;r:.=Dx dt
( l)
D • th• dllutlo• •ate (11•• •ate eaterlna t•e
t)Ht:l!'efC'l'e if k "7 l) the YalUfb U Wi dt
(3)
D? k. t1i. i«t rutg&thre and the o:rg&l.'li«tu'I eea.etu.it:t~tion will dt
•••r•ase, ev•ntuallf to ••••• tber•t•re the cultu•e will
p,~ = 0 •nd :.: l~ OO!Uita:nt; •t
•t•t~ t•• effect 01 dilution •ate
awtn1 oat at • aonae ••tl•n a.
y = ""''i-·---s1 ... s
•
(5)
to cell
co~ .. D S (6) j{
(1)
bour~ k.,. O.
_,_
ean. t••refel'e •• •Xpl'e•••• &8 11. • • + k yl
••••trat• ••••vat •r k • yl uc. - •)
(8)
(t)
la t•• ••••l•p•it •f •••ti••••• f1•• ••••tl••• t•• c••-'• ••t• l• ueua11J ••••-• t• II• a ••••taat
l•&etl•• of tile ••ll•t•at• r•••••l rate1 (10)
ct••• .,,, U. • • J.L. • ks/Y cat Ydt
(11)
"•• '' .. ,, ••••••• , ......... (10) .... , •••
••••1•• ••••••• of a ••all •••••• ef ••ll•t••t• •••--pttea
•Ill•• i• ••••••• •••• if •• crewtla •••••• •• tlaat
... •••
•••
.U. • • C ax + kx/Y1"> .,
.ti. • k •• -<• + k1/Y1) .. , ...... , .. (13) ••k•• t.t
rt•J.• Y at Y&l'teu J.eyeJ.s
y. k -"• ...... , .... y. k
n + (k/YI)
(18)
P•••t.111• to •••P•t• , .. Of ke Br d•flntttoa
(14)
(11)
• A
.!!, =:: D S1 - D S .,.,. x <n + k/Y1 > (16) tit
ste•dY ~tate •ondi t1ons wht1u1 4.x = o w• dt
D • k~ (1 • e·• r,
fl lB ( ka ) k 11 .... D
1 . l ... -=Yd'- -1s1 'D -
( 17)
( l.10
(20)
valua
u @I ( s:; ) c sl k 'f
OU)
s
nutrit to
eul ture.
b' ••an• •f the aAe•••tat.
aueb $ft~iehmentg a~• t•s
rl•a• war• of dlreettn1
lealar •••Pl• of water ••• dl~eu•••d.
.tUHi QWStU'ibtHi
I.on o:f :intet'•
aetlon~ ••tween twe or more •P••I•• af ba•ter
11~1
at aar point on th•
•Ith t•• s•••••tlaa tl••• of eaok or t
th~ er1aai•~~ •••• 1•••n wltb ••••
• Shlndala. et al ( ) •h•••d tbe lnteraetloa ot
has ne ef feet an the other.
The b~eterial 1rowt• was shown to fol
a relatl•D•hlp that ••• nat llnea~.
culture •h•• o•clllatlea1 In s•••th rat•
of dllutl•• rat•
ebae1•. latien a•a•t• were done by tke •l•ctrenlo
Coult•r Counte~ ••tbod.
The initial object of this reeearch was to tna,uly a
raudo• mixed culture in a continuous flcnr 1yatem. The initial
plan was to detemiae the amowt of variation of oraaniem in
the mixed oulture and by foretna environmental eon41tious to
be able to select .simple: species from the m11'ture.
tube.
not <Umtttttuen\s &f tlu1 $lf.m.r.) .tc ·the ~ample l;)y ~bet
P•tt<ott•fhu:uuuu· aethod.
Whcui sllae 'luuua.c1iu11 't•0 h4UiVJ t~e tf<J•••l walls
we~~ f.IC th • t~J!llt tublt • i!lli \HU!! UIJ 11
t O~ CHI!· .a
i'U$1l
ealaYed at 15 p.•.i• fOI' 15 .$ • b pro.:uHss wae
.t. 1 'l'.O•~.
•U•
1-
AIR INTM<E
(~ A
B
I.
tb• •••ptla aeries of tbe
PY•Vl•••lr •eatlan•• except •• eo•1taRt wa•
••quired, ••r• e n•ot•d to a 11-11ter pyrex re•ervoir
~ ••• •applied to tb1• r•••
CC Fss. ZJ and tb••
i' i~oi:t the
tub•· xqow
1rawtb •••••l• were •lllllt•r
fla$k• with ~G$ ~ a~~ •ffl~•~t tub~•
•••s • t• p•••lt ove•flow at aoo •lltllt•r•.
WI$ :re at
Fi~. 2}.
•o•• •h•k•r ••••S•ted •f a pl board
by fo•r ooll epr ab••• a b•••·
s•• pl ••• eenneot•d a •teel aanaectln1
FOtil to a at•$1 tlywatu!l ttt attain 4 thJ<.ee b 8t •
f 1p•h•el wa• driven br a
E tri~ ~~t$r, Th•
-19·
the entire apparatua wa• co1111ected and auto-
c lavecl for 15 lliaut•• at lS , ••• 1. the arowth proce••
took place in a 2o•c± 1 c• con.teat temperature room.
After tbe arowth v••••l• were partially filled
with llediua, uoh ••• 1d.entically inoculated with the
rudom culture grown in the prwiou• experiment.
------------·-------------..
B
PUMP
Figure Z
D
:;: 0 ..J u.
3. I• th• 4•f1Md caltv• •terf.meata tile
ceetl .... flew a,,...atu MU1ete4 of a 12•U.ta
r .. enolr f ... l .. an lrl...,._ f1-ak ooataild.ag 116
allllltaa with afflut111t throuah a &laaa tube a7atem
(l'f.1. 3). Aeratioa vu ac...,Uahed b7 1tlowlq air from
the 18oratory CGlllpr .. ae4 &11' •1•t• (Ftg. 3) into tile
culture ...... 1 ~ • cottoa fltlaaed al••• t .....
The culture ...... , vu lae14 1• a 30•c water ltath, aacl
aecli• •• fe4. witlt a perlataU.o ,_, (8f.p&110tor
eo.pay, Middleport, lew York). MapetS.e llb1 .. of
tile .cmlt•r• ,, .. ,.1 .., t11111ploJed. The •Y•t• la ahowa
ln figure 3.
a_,1 .. WR• takea froa tbe af flaent tube fer
retroff•lla\le•• ... Coult• countlq. One m11111t•r
of tbe ._,1. •• aMecl to 99 milUf.tera of a Hlvtioa
tbat ceataiaed 0,9 ar-. of lael per 100 miUUtar•
of 411tl1le4 wtar. rua ._,1. •• thea couatecl 1»1
tile elfftl'oale Coulter Couater with a 50 alcron apertva.
Tbe Coulter Coater had ••ttlnp of the follow1 .. :
1) thrulaolcl re.Mlq of 4 1 pln aelectioa of 3 1
aad aa .,_.t•I'• ovrr•t ••tt1ag of 7.
After aMl .. 10 U.tara of Mcl•(Table Z)
to tbe ruenolr the .,,.ratu •• conaecte4 aacl ••to·
clavecl at 15 p.a.1. for 15 al1111tu. rollowiq coollq
tbe vlt•i•• Wft& a44e4 to the aeclim aacl opel'&tioa of tbe
ter th~ grewth wes••l content~ had reaehed
111 •lllllt•r•, pamplftS ••• •topped ~n tneculu~ could
be 8dded ta th~ grewth vea•el•. The air Intake w•• al•• diaeonneeted lrom the labarat•rJ eoapres•ed air
av•••• to pr&went eonta•inatlon of the media r••ervolr,
anti t& prayf!ln t 11u1tedla t@ wtushout of the !tuH:n1ltu11,
Culture!!!! ot 'B.d. c~l'•-q!lt and .l!u • .. ~ui:rcs~~.e,, whS.ch
Wl't'«J ctown in t•J!lt tuh•illl f'.!f ltlfHHa (Table 2) at S7°C
w•r• usu!td 1u11 ino«11ultun. ln 1 t: tally ~P.!~.!.! waui.1 added
ta the 1row~b •easels of the continuous flow •r•tea. The or1a•l•ms were g•own in bateh oultu•e to• 11 hour~
bet••• stQrtlns continuous flow. Aft&r the population
of 81 •~E•s• al•ne waa det•••lned at ••••~•l flow rate~.
4. urogen~,u; wes added to the iay9tem without interupttns
tbe flow.
B
AtR
fi9ure 3.
B. 9MlturM el tHIE !tbtw•• Cult•i9 ••ed ,. cm f1r1t tw ..,..laeatl
were eellected by 1 ... 1a1 tlae arowtb vee1el1 of tM
Wttal aperlaeat opea to tM atm.,Mre for ... ..._
expe1ure to ra.._ Mcterla. The t7P8• of l:tacterla
prueat in the culture,wres ... u l'oQ witla a •t-ter
of rovply OM aicroa, 1cae eacapaulated and ._. not;
tarp ro41 wttll .U.-ter• •• Iara• •• 5.0 atcrou,
.... euapulat .. alld a.e aot; 1Mll an4 Iara• cocei
.... free and otllc;• tr..,.. la •U•. There wu aln
a arut IUllter of 1U.me flocnlu Mtla lara• a1ld IMll.
Bulllg HUii (ltr• l) an4 AtroMISS
'V'MM' (ltTaln 1) uaed la tM .. ff.Md culture apeYlaeat•
were •talaed from die nltul'• eellectlon of tlae Mcterf.oloa
..,.rtaeat, Vlrpala hl)'tedmlc lutltute. 11 nrnt
11 a ro4 alaaped erpal•, l.O to 1.2 by 3.0 to s.o microu,
with •caur• -.. aerol:ttc, fanltatlft ••••le, .... 117
ocnrtaa la ellort to toa1 taaaled .Uiaa. The epecl••
•ult wltk wu fl1-tou, eacapeulated aad ar• vartule.
Opt.._ arowth occur• at 30•c. A. IH!UMI 11 • rot 1baped
orpal•, 0.5 to O.I by 1.0 to 2.1 llteron. oenrtaa
•l-larly, ._,..lated, ar• aegatlft, urol:tlc. aa• pn'vMr. 8pt..._ anwtll occur• at 30•c. Belk culture• ._..
iaitlally arowa •• Difee CJ•tt .. tl')'ptlc aaar tlaea transferred
by uae of a loop ..-1. to tut tubes of medt• (table 2).
C. 9.P•i<ifLtjgfl. an(\ f£8R•.~~tjpn g:t Med~!
.~...,, ............ of tbe e~dUon e~n l~ l
w~re u1:utd i'a
~itm of c~sition. in
uu1d <r;U. cultu.t'ea.
in
wll!ra diuolved
a m1Hpotte rn .. b:rane:
ddin9d
led wat~n·
lter to
used, atwaya morll:li th.al\ 5
sto,ck so wtitre added to tb~
of media.
ware
of t:he vitaod.n
li tet" rGaervoir
l
~i~ ! ~nens 9JM!nt1tx
fotanium pbospMte. monobaetc (KH2ro4) 6 g
Po~asdum phosphate, diabad•~ o:.2HP04) g
• 1
(MH4)2 S04
D~trose (c6u'.! 2 06 • e2o
Distil b1d Water
0.2 g
O.O(HO i
3.0 g
2.0 g
•II•
Table 2
§i!swcm•t
Dextroee (C6H12o6 • a2o
<•4>2•04 K B2104
~lll'04
Socllum Citrate 2 a2o Ha so4 • 1 a2o Diat1lled Water
Viteip
for lxperimllat C and D
Biotin
Calcium fantothenate
1 • inoaitol
Thiamine
Pyrid oxine
Qyytitx
4 I
2 I
6 I
14 I
1 I
0.2 I
10 liter•
Quantity/100 al of a2o
10.0 ..
1.0 ..
s.o .. 1.0 ..
200 ..
Iu the &.'!:peri.metlts with random mi~ed cultures the
•l di 1u.tion rate.; werEi kept coru1tant at D • 0. 6 hr for the
Population as a fu~ction of time ia given in fig. 4. The
popul•tton suuwa to oac:U late randomly. This great oscillation
h in U.ne with tne results of C.uell 6't al ( Ht64).
Since random oscillattc:ms of population leve1s occurred
production waa great as in the open mixed culture experiment~.
There was no way to do quantitative work because of clump.a
growtb floccules similar to activated a 1.udge floe.cutes were
noted. Abo, frO&'l1 visual observations sHme formed in the
vesse a at different rates and variations were evident from
CIO l 0 ....
12.0 j I ! l 10.0 1 I
I I l .,, 8.0 ~
~ l
..... G>
(.)
I l
ti(! p """ 6.0 -i ~·
.,..j ;t Vl
Iii ... ,.. """ 4.0
2.0
0 1.0 2 .o
-1 .D .. 0.6 Hr
-1 '"' 0.2 Hr
--.------·------.----·----·r-·-·----·--~--··---,.-·-··----·-·t··---·-·----
3. 0 4.0 5.0 6.0 7.0 8.0 Hours After Run Began
Figure 4 Population Changes in a Random Mixed Culture
the start. After continuous flow operacion was stopped,
the a lime cm th!!! $id~$ of" the vesa• l& took from one to four
w~ekllJ of batch culture to slough off. A gre;ater time was
required for the morQ dense dime to slough th6 container
walls.
Since resu from tluui~ random mbed culture growth
syatems ware hard to interpret, it va• decided to de pofulation
studies on pure. cult~.u:H of l:uu::taria at var1011s dilut::lon rates.
A different medium {Table 2) • 1ncn:-e suited to the selected
cultures. liiB& used. Sterile tttst tubes of thb medium were
1.ooculated \1ith the various orpnbms. Thi.I batch method of
growth provided an iudex of the ability of the organifn1~• to
grm;~ ia tl1i.1J m~ia. &esulu from thb ttiHlt are •1u:r;.rn i.n Table 3.
Table 3
Growth of different cest culturtuJ in the chemically
defined medium (Table 2)
Organism
S~a2nxio~9ccus ~R&~e~m!d~a
la~111us c•[;eus
f\erQba~ter ~er21en$Jt
l,rotau! wlar&s
Ser:c:atia r&n."c.rusearuJ
~s.cherr,iel\4. co.Ji
Siu.:ch!rP?!lc~~ eet:!Ji.tti.\'\fl
Growth
0
·tt
+H
0
0
++++
-++++
:rate. !at~r be
W8$ i,: a cui cure
!b.....!~F.fJl~;tte,J. d o\rerstoH B. cereu1.
or floes
to tbe bi1hest dilution rate cei
reduction in population did not follow
in culture. It
the two apeci~s
Popuhu:::ion le;;els of
and e()ntinued up -1 0.72 h:t • The
flow theory
-co I 0 --
s.o~ I l 7 .o -1 l i
I 6.01
I i
5.0 ~ I
l I :l i {
4.0 -j
J ~ ' J I !
3.0 i ., I l !
I 2.0 1
l l ~
l 1.0 J
j l·
! I
0 1 0
-33-
Petroff-Hausser Counts
8.0
7 .o
6.0
5.0
~4.0 I l 3.0 ! ( f
! j
I )... 2.0 ( ;.
~ '
-, ------T-----·----.---··----.-·------r----r--·----i-0.2 0.4 0. 6 0.8 1.0
Figure 5 Population of B. cereus as a function of Dilution Rate
-'° I 0 --Ul --~ u
6.
Aft•t, the
count ~-;,; to
1<r.a•
corud.a Ot
D
wa1
det.e~ined that 1C1t
and
~ o. , 1t
• i
t:o
di 1:'$.telil,
froo1
•on
it
l
t1j
populatio11 •l hr
f
rate tUHMl
!nte~:tate
not
~ult.uro in
..... a
Oo • 0.8 0 ..... ~ u ~
~ u ~ 0 ~ 0.6 ~
~
0 ~ u ~
u ~ u M 0.4 ~ ~
0 s 10 IS 20 2S 30 Hours after lnnoculation of A. aerogenes
Figure 6 Trends of Total Counts of.Baclilus cereus and Aerobacter aerogenes vs Time after lnnoculation of A. aerogenea
• (.,J r
\
I"-• 0 ~
>< .,, u c: ;:I
8 M ~ .., ..... ;::I
8
.,37 ..
6.0
.5 .o
4.0
-l 3.0 ~ I> - 0.370 hr
•4\ A £... ~ I & -/ir
2~0 ~ I
1.0 J
0 -+---------...... ----------..---~-----,..-----------r----------0 o.s . l.O 1.5
Time (lirs.) 2.0
Figure 7 Population Counts of a Culture of Bacillus cereus and Aerobacter aprogenes . by the Coulter Counter Method
e~~i~re ~o rafutcm
population •e•~d to
swi~1· popuJation at·lil
ScrM~ tActcr«t
J latiotu~
1n.terf$& i.: and
eatuie f fit"et the varittb '·• iuoculaticn
interaction
t:bi! t:x.·e• awblmet' ~v• oseH illted
1 it~creaeed unt1 v•ll'tU~ t be
flow c•.ltur• syst.-
s and &ict
.iuu;;,m Si t.e«ui y• 1;H:.a t *-
became attached tu
rat• of die 1
th~ $lim4t eont:f.muil
I {;If f
gr~th pattern~.
that
~II
IS
l'.·and"°1~
l({
OOL
., ...
level• clecrea•ed •• clUutioa ratu 1acrea•ed. fopulation
lft818 d14 aot follft coatlJmoua c.ltuee tbeo17 in that
population level• decr .. •ed 1reduall7 a.er a •eri•• of
di batloa ratu inatud of decr••iaa •barply at tbe
critical clUution rate. Since I• WN fol'Mll ea,.ulea
aad soaa It-.- attadled to tbe arewtb .uael walh, it
•• tmpeaaU.te to provide the coaatent control over arewtb
factor• that ...... 111 would be espected in a coatinuoue
flw •7•t•. IU.11• vlliah eatrapped th•• orpni ... could
poeaibl7 lane clecr•aed ... , ... detention ancl incr••ed
os1aen •"PPlY per uait volume by clur ... iaa tbe volume
of coatat.Mr. Also tbe ti• intenat required for wa•bout
of bacteria aM aetahU.c wute pl'Ntacta *>ulcl U.. been
iacruaed fr• theae iaillu belaa lwlcl firm in tbe •lime
couected to tbe veaael wall.
Wban A1 IHllWI •• added to the •J'•t• already
contaialaa I, u.rw, it,••• beU.eved that tbe •re rapU
anvlaa A• MU• .. would .-pletel7 take over tbe •Y•t•• Total pepulation le.el• deer••_. after tbe acldltloa of
6, ..,..,., htnff•Bauaer 11DUDta •bowed after 1..eral
daya tbat tlae population vaa oompoa_. of 78' of As nrpam•
encl lOl of Ir um1. It u beU.....a tut t1ae only reaaoa
tbat 11 •w wu .. t wuW ...,1etel7 from tlw •Jet•
waa ........ of tile COlltilBIOWI ret.culation of tllia
orpnl• fr. the alime on the container •lla.
in
quit"
l. of
-41-
By finding the condition of minimum slime production
a greater number of mixed cultures can then be studied
in the future.
Other research suggestions are:
1. The affect of sinusoidal application of flow
to a defined mixed culture of B. cereus and
A. aerogenes to determine whether there is an
immediate response in population levels.
2. The use of sinusoidal application of medium
to a defined mixed culture of B. cereus and
A. aerogenes to determine the growth response
of these organisms to food supply.
3. The use of sinusoidal pH variance on mixed
cultures in general to determine the growth
responses of these organisms to pH.
These are only a few suggestions for future research projects
on mixed cultures, but much research is still needed.
2. s i~ produe;;.ic:m incrl'ilaa11:1d s the
mi:hed cu t:ure l'UUS and 'l>l'lil3 control
as
a .., Population eve I of ., .
a 1harp red.~H".,t:ion in
ly aver a ••ri•• of
free iquid.
An astlpt1e ccn:u:tnuou.s flow syster.i fen: the study of a
random mi:u~d Cl.\ tura was deecribed. The quick production of
great advantagtt ever the syfltem with co1·uuant e:1tposure to
the atmospher~. Activated sh.Jdgfa ike t !o,~cules and 1
were noted to grew at tlu;~e different rate8 in the 1..1.u:ee
idendc.a irowth veueh.
~act l luti cex·et.ls population liltve ls were noted at various
flow rates in a continuous
formed and some: 31 im$ was ootad cor:uiected to the growth vessel
walls. Population lwcda taken by Coulter Counter method did
not confor!lft to the contiru.tous f a pure culture in
that there was not an i~edhte ~uction in popuhition level
at the ct"it:lcal dilution r~te but: a series of reductions
over & range of several dilution rat:.u.
.<;.~;eus and Ae,t:~bacter ae:rogEui~" were s A uduetion
in population of t:he culture from~ ch.at of: a
pure culture of i •. cer,e.!lJ. was noted.
shooed seven l ~ya
mixed culture w.iu appro:dm.aeely
Petrcff•IiautlH~r counting
population of the
of tile ttr·i.gina • &,
a11ir1tos,e~e1 population eounu vere taktm iat.: S&\!'(:ral di h.ttion
:rates. Thefle lev~ls did iwt follow contiooou!S :flow theory for
was ooted that) the count at a lm1t:r d:Uution rate. It wa3
decided that sli~e on tb8 w.dh; of the gro~t.h vcuuutl ccrntiAu41 ly
to control
fl ow prcc~1H11 •
Also thh n~thod 'tt.lllS too laborious and it \<J'!Ut almost
aad advice !•om hi• tbe•i• adwi••r, • H, R. sa11 te
Dr. w. A. Pa••••• to• bl~ 1••••••~ ••eo••~s~ment •ft~•••
darlns this eear~• •f studJ; to • B. G. Willard fer
bi• ti~• •••Ins techaSea1 •••lstance; to my oell••I•••
who f~und tS•e amld~I their awn ••s•arob l••••t Ion
io lend a belpint; ~uuu~ and •UtCJ)~t"a1'•1Uuu1t, te the N•tional
stltate of B•alth I•~ financial help and to th• Ylr•l•I•
T•ob At•letle soelatloa I•• time and P•••l••lan te
•••• sraduate •t~dy while •mployed by tbea.
A •e•t er sratltude I• •l•• extended to •Y
The vita has been removed from the scanned document
, N. Yi.•
llt.
1964.
J ey) J. ~; • '
4. liar~ert. ll. > E th J Tt1tl • a. c. t
i.tt~• Cu.H:ura o.t' J ~ 1 a.rid
G58,
•
7. Olmcla, A., ad lobaJ'&IAl, II., "Productioa of I UM
•••tw• lD KbM Calblr.. .. ....... Jf 2 ! W!!llsp
aa4 Aet.WslR Y'M1t"'&•" llhll• 191, 1201-1, 1961.
a. ••rar, 1.. 1 .... a.,.an, M. 1., "lntnaetS... of the
Ol:al Hicni»S..ta, • a,.t .. for the Defl.Md ltudJ of
IUxecl c.aicua," butt4'111 ti 'M llCUD' w
t. ldml&e, c. i.., "The A.ctlwtecl 11-.. ln-• u a
Ce•ttawu flew Calture," !IS• •9' IM't !RU• 526-
ssa, .,.., ••. 1H4.
11. lkhctala1 A., -._,, II. l. 111, lrlea1 I. I..; a4
CallMart, &., ....._..a.ttue lateraecteu," al!R'Ml d. IMSMMltV• It, Ml•6t6, Mna, 1965.
11. lllWMlala, A., "G'N'Wth lB Mbeil Calttr• of MlCl'ON'palw,"
Dl1aertatioa &tr IHcer of rtdl ..... J lB Cf.vtl laaf.aeertaa
fna firalala lolytHbaio lutlblte, 1•114 1 .._.. .. , 196'.
11. 1'u Itel, c. 1., "llatual lelHtioe la the Mlereltlal
W.l'ld," Janll ,, e=eu1 RllWtitlt&t• tJ, zo1.111,
195J.
In th.~ Cou ! ter Celntt.er a guspftsion is Nd• to
tlu:ol.lgh a aJMH ap~rture in a &laH 'Wall separa.t41s the
su~pension :bu:.o tl>to aleeti·ical isolated po:t·tions. lHectrodes
placed in the ~uspe.nt.rion on ~ithe.r side th• wal are
oot•mectfid tc 4 direct eun·e-nt SQpply. the total curl'e'!lt
passi~ through tlli\ S~8pt!UiOtl. uet~een WUU::
p.ua
pordoti vari•s its area,
oi :ta thfl aperture w:iU be very much bigb.er
than th• ~•8t the susp&~$1on. a~d tn~ eu~r~nt be•
tween thf! &leotrode~ will depend t on
t'e"iatanca this t~shta:nce l ba con.atatu: •
when a parti.ele ei:en the ~u.une:l a reduction i!!l. the of
th~ fluid bt th~ ap•rt:urti oectn:-e 1 tbe raei:iu;al1.~e riiu-1111 •
currant bet:wee.n al•c~rod$• A• a particle p:1U1tJe$
apertur• the cunent will
to its or:igioal levelt magnitud.•
11 the 'VOl~e of partit;:le.
conversion factor
diamete:r of a ephare
l and th.en riHt again
cu:r:rent:
use a 8uitable
tbrC11osbold
d~te~nation
above whi~h puls1H s.1."e counted euablt>.s the
~d!:tl
}t!
Jlll
llll
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ill1
tll!
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11
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•
s~ le i• ¢~illlt:ei:A
ap•rture. _,,.u<•·A~lB!lo 1$
the mill1i'P'"1'1Y"il1
oo~tacts
ccat~lcts
JU!!CO~d
alway• coiuur.iid
f ir&t elecctrode11
f laid a. A ~d;lll timt" ell
atopP*'f
pardcl«u!l
flowius
pert(ld §tboot s~11uzoud• watt U$ed tbroua~ut this res~H•rch.
'fhi~ as1i1ted a great d~l in tbe tr1!1l~lt.tentt
pltiqin1 the 5:0 •tcron orifi<:e b;y reducing tia n•c~1utsry
for u11i£om wlwne:B ff>l' couatitta+ Umel' f.bo tU.:f.mi:uted
the t:Lme coosaini teduaiq;u~
unoutrer af tei- cout. ea U.tiratton at~
tn thti
CU!fl:.~~~~lll& Q f this
Moi11 ----iompllfier
..._.. ld.•t• , .. titlu of vttat.u er lald.•iter•
Id.pt enae an•• en:or• l• tke ruulta of tke acrtttoaal part of dd• wrk, aad larp _._.. of dut parclelu Id.Pt ef feet tke Coulter Glnmter Cftlltl or aue tile SO 111.•n•
ortftce to plq, lt •• ....,..,. to take ar•t ear• ta ti.
cl••laa of au aJ.unare u8'. '111.9 11a11War• •• ff.rat
Hake4 o 11100 Ml•tUla 71. 4eter,_t. (Llllltro auild.oal
Cellpa1lJ, llev Hafta, c:. ... ctnt) for Mffl'al hou• aatl tha
1cn&Mt8' ud rtue4 10 tlau la tap •t•r aafl I ti.au o
4f.ati118' •t•. '111.9 11&•-r• •• tkea allakea lt7 haa4 aa4
tavert8'.,..,.,.. towel• ud left o the air to •rJ• AU
.. ..._. _.. tllat coataOed ...,1.. i.r tu C..lt• Glnmt•
ODt1Bt1 were rtu8' 5 t._.. vltb 411ttll .. •t•r ltefere
atelaa ued. tut •• u.t o the pr.,_atioa of cu -.ie
for tu fetroff•Baua• Mttlod of COUDttaa aa4 al• .... to
ceUect ...,1 .. .,.. ••Md ud riu8' •• p1nioul7
Mlltioaecl aeept tU -.. .,... ctrtad o aa .... for over I b.oura
at 200•c for aterllt .. tl••· nae pf.pate• ......... la 11100 71. •l•tloa for •r• than
34 heva anti tUa rtuad wttb aa auc-tlc oeau ...... 4ftlce for
at luat oae -.. o aold tap vat•. !bale plpett• ••• tUa
pla_. ta al•a.- coatalw• aad placed ta •• ova at 200•c for
atarlltut&oa.
OSTIACT
tepulatloD levela of a aixed culture that waa .-1ently
apo•ed to bacteria in the at:ID•phere wa• atucH.ed at varioua
conataat diluttn ratu. &aadola fluctuatiou iD the free n1-er
population were noted. Aa aaeptic ceatimaoua flow •1•t• proved
of DO p-.. t 8'vantage over that which bacl .-1eat iDDOculatlon,
however, aliM productioa did not foll• identical FOWth patteru
la tu .. iclential arowth ..... i..
Coulter eeunta were made on a pure culture of I• ur1111,
arowa in a ceatlnuou• flow •J•t• at yarioua clilutioa rat••·
Thea• eounta clicl aot foll• ~ flow theory for a pure
culture l• that there •• DO •herp clrop f.D count at the critical
dllutloD rate but arac&ual recluctlou over a rana• of aeyeral
clUutioa ratu.
Total populatioD count• by the Coulter Counter were made
oa a cleftmcl aixed culture of a, cuw allCI A, pm11Mf. After
a •neral day• retroff•llau••er ceuata •bew.S that 70'& of the
,.,.1atloD ••A, '"PllP''• Total population waa reduced from
that of a pure culture of ! 1 urwt. st .. d7•atate populatlou were
noted at YArioua cU.lutloD ratu. Thea• at ... J••tatu • bowner • ell.cl
not foll• eontlnuou• flow theory for a pure culture la that
larger cowau were aot.S at a hiah•r clllutioa rate than .... cowat•
at a lower dilution rate. lt • ....,... that alime on ltae arovth YU••l•'
wall• continuall7 cbaq.S the .... s.romeat had a , .... t•r effe.:t and ucle
it .... ••I.bl• to control all the ...,,lromaautal factor• av• in a
contf.mulue fl• procua.