CHEMISTRY INVESTIGATORY PROJECT
MADE BY ROHAN
STUDY OF DIGESTION OF Page 1
STARCH BY SALIVARY AMYLASE AND EFFECT OF pH AND TEMPERATURE ON IT
Page 2
Lab certifcateMollyJa ne This is to certiy that Master Rohan Kumar, student o class 12th has successully completed her inestigatory pro!ect in chemistry on the topic as prescribed by the "#$% under or the &'$$"% under the guidance o Mrs( $arita &mbrose(
Teacher)s $ign %*aminer Page +
Acknowledge ment I thnk m! chem"#t$! teche$ Mrs( $arita &mbrose %o$ g"&"ng me nece##$! g'"dnce %o$ th"# "n&e#t"gto$! ($o)ect on &"T'- . $&L'/&R0 &M0L&$%* I wo'ld l#o l"ke to thnk o'$ #chool Page
mngement 'tho$"t"e# %o$ ($o&"d"ng me ll the $e#o'$ce# tht I needed %o$ th"# ($o)ect*
"ontents Int$od'ct"on E+(e$"ment , E+(e$"ment E+(e$"ment .
• • • •
•
B"/l"og$(h!
Int$od'ct"on Page
%ery health boo3 insists on the che4ing o ood( 5ae you eer thought oer this6 The act o che4ing stimulates the e*cretion o salia( $alia mi*es up 4ith the ood and helps its digestion( That is, the en7yme ptyalin or amylase present in human salia hydrolyses the big molecules o ood into many smaller molecules, or e*ample starch into monosaccharide maltase and glucose, proteins into amino acids and ats into atty acids and glycerol( Thus salia not only helps in digestion o ood but conerts it into energy generating substances( .urther, en7ymes and their actiity are ery sensitie to temperature and p5(
b!ectie 101 Page 8
To #t'd! the d"ge#t"on o% #t$ch /! #l"&*
&pparatus01 Te#t t'/e#2 Te#t t'/e #tnd2 , d$o((e$2 Beke$# nd Sto( 3tch
"hemicals01 St$ch nd Iod"ne Sol't"on
Procedure9: 1("ollection o $alia9 : Rinse you mouth thoroughly 4ith cold 4ater and ensure that it does not contain any ood particles( -o4 ta3e about 2;mL o Lu3e 4arm 4ater in the mouth and gargle or about three minutes so that salia mi*es up 4ell 4ith it( $pit this into a bea3er( .ilter, i there is any suspended impurity( "lear fltrate is salia solution and contains en7yme ptyalin( 2( Preparation o $tarch $olution9 : Ta3e about ;(g o starch in a 1;;mL bea3er and add enough 4ater to ma3e a paste( Ta3e mL o the starch solution in a test tube( &dd 2mL o salia solution into it( Mi* the solution 4ell by sha3ing the tube careully and start a stop 4atch( =b> &ter 1 minute ta3e out t4o drops o the mi*ture solution rom the test tube 4ith the help o a dropper and flter solution( -ote the Page ?
color produced, i any transer it into another test tube containing about 1mL o 1@ iodine( =c> Repeat this test ater eery 1 minute ta3ing 2 drops o them mi*ture solution and resh 1@iodint solution( "ontinue until the test sho4s no blue color( Record the time and blue color intensity(
bseration9: Time 4 5 6 7 =min> "olor Dee( Bl'e Bl'e Bl'e 8"ght 'ntensi Bl'e Bl'e ty &bsence o blue color on addition to iodine solution means absence o starch in the mi*ture solution( That is 4hole o the starch has got digested or hydroly7ed(
"onclusion9: $tarch gets hydroly7ed by salia amylase*
b!ectie 29: To #t'd! the e9ect o% tem(e$t'$e on the d"ge#t"on o% #t$ch /! #l"&
&pparatus9: Te#t T'/e#2 Te#t1t'/e #tnd2 , d$o((e$2 Beke$# nd A the$momete$ Page A
"hemicals9: St$ch nd ,: Iod"ne Sol't"on
Procedure9: =a> Prepare the starch and salia solution as described in ob!ectie 1( =b> Ta3e + test tubes and label 1, 2 B +( =c> &dd mL o the starch solution, 2mL o the salia solution and mL, 4ater o each test tube( =d> Mi* the solution o each tube, 4ell by sha3ing it careully( =e> Place the test tube no( 1 in 4ater at room temperature, test tube no( 2 in a bea3er containing 4ater at ;o" and test tube no( + in boiling 4ater( => &ter minutes, obsere the color change on mi*ing 2 drops o the mi*ture o eery tube 4ith 1mL o 1@ iodine solution( -ote the intensity o blue colored orm(
bseration9: T'M%=mins > 4 5 6
RM T%MP Bl'e colo$ Bl'e colo$ Bl'e colo$ Bl'e colo$ Page E
LC%R T%MP Bl'e colo$ Bl'e colo$ Bl'e colo$ Bl'e colo$
5'D T%M Bl'e Bl'e Bl'e Bl'e
7 ,4 ,,5
Bl'e colo$ Bl'e colo$ Bl'e colo$ No chnge
Bl'e Bl'e Bl'e Bl'e
colo$ colo$ colo$ colo$
Bl'e Bl'e Bl'e Bl'e
't ta3es less time to reach a chromic point at +? o" as the en7yme is ma*imum actie at this temperature 4hile at higher and lo4er temperature more time is ta3en to reach the same point( &bsence o blue color means absence o starch in the mi*ture( 'n other 4ords, digestion o 4hole o the starch(
Temperature 8owe$ No$ml H"ghe$
"hange in Bl'e colo$ No chnge Bl'e colo$
"onclusion9: Temperature aFects the digestion by starch by salia(
Page 1;
b!ectie +9: To #t'd! the e9ect o% (H on the #l"&$! d"ge#t"on o% #t$ch
&pparatus9: Te#t t'/e#2 Te#t t'/e #tnd2 , d$o((e$2 Beke$#
"hemicals9: St$ch2 ,: "od"ne #ol't"on2 d"l* NOH
Procedure9: ;< P$e($e the #t$ch nd #l"& #ol't"on # de#c$"/ed "n o/)ect"&e ,* ;/< Tke . clen te#t t'/e# nd l/el them # ,2 - = .* ;c< Add >m8 o% the #t$ch nd -m8 o% the #l"& #ol't"on "n ech te#t t'/e* ;d< Now dd -m8 o% wte$ "n te#t t'/e no* ,2 -m8 o% d"l* HC8 "n te#t t'/e no* - nd -m8 o% d"l* NOH #ol't"on "n te#t t'/e no* .* ;e< ?ee( the th$ee te#t t'/e# "n wte$ t $oom tem(e$t'$e %o$ /o't ,4 m"n'te#* ;%< Te#t - d$o(# o% the #ol't"on o% ech te#t t'/e w"th ,: "od"ne #ol't"on nd o/#e$&e the %ollow"ng*
bseration9: Page 11
Test tube number ,* ;#t$ch @ #l"&< -*#t$ch @ #l"& @d"l* HC8< .*;#t$ch @ #l"& @ d"l* NOH<
"olor produc 1@ iodine so No /l'e colo$* Bl'e colo$ Bl'e colo$
"onclusion9: p5 aFects the digestion o starch by salia( That is amylase hydrolysis o starch does not ta3e place in the acidic or al3aline medium(
#ibliography 1(
-"%RT te*tboo3
Page 12
2(
Doogle
+(
Ci3ipedia
Page 1+
