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Some physical constants of the oil of Fusarium lini

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This thesis, having been approved by the
special Faculty Committee, is accepted by
the Committee on Graduate Study o f the
University o f Wyoming,
in partial fu lfillm en t o f the requirements
fo r the degree
..
.........
Chairman o f the Committee on Graduate Study.
Secretary.
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission.
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission.
SOME PHYSICAL CONSTANTS OF THE
OIL OF FUSARIUM LINI
by
Charles Francis Kinahan
Thesis submitted to the Department
of Chemistry
and the Committee on Grad­
uate Study at the University of Wyoming,
in
partial fulfillment
of the require­
ments for the degree of
Master of Arts
Laramie, Wyoming
1940
UNIV. WY9. LIBRARY
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TABLE OF CONTENTS
Page
List of Ta ble s .............................................. iii
Introduction................................................
1
3
Ex p eri me nta l................................
Growth of F u n g u s ...................................... 3
Preparation of Fungus for Extraction.................
5
Extraction of Oil from F u n g u s ................
6
Determination of Some Physical Constants of
the O i l ................................................
1. •Specific Gravity
at 25°/25°C.............
8
9
2.
Refractive Index
at 20°C ................ 10
3.
Iodine Number (Hanus Method)............... 11
4.
Saponification N u m b e r ...........
5.
Per Cent Soluble Acids Calculated as
13
Butyric A c i d ............ ............ ....... 15
6.
Hehner N u m b e r ................................ 16
7.
Acid V a l u e ................................. ..17
8.
Per Cent of Free Acid Calculated as
Oleic A c i d ...................................18
Discussion of R e s u l t s .......................................19
Sum mary.
..............................................
Bibliography................................................ 22
ii
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21
LIST OF TABLES
Page
Table 1 ............................
3
Table I I ...........................
7
Table I I I .......................... 10
Table I V ............................ 11
Table V ............................. 12
Table V I ............................ 14
Table V I I ...........................18
Table V I I I ..........................20
iii
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SOME PHYSICAL CONSTANTS OF THE
OIL OF FUSARIUM LINI
Introduction
Some work has been done on the products of metabolism
of Fusarium l i n i . the fungus of flax wilt.
Anderson, M or­
row and Willaman^ found after extensive investigation that
the principal products of metabolism were carbon dioxide and
ethyl alcohol, with smaller amounts of organic acids.
When
the fungus was grown on a carbohydrate medium, these pro­
ducts accounted for 90# of the carbon contained in the car­
bohydrate.
In 1926, Willaman and Letcher^ reported that al­
though alcohol was produced there were also traces of ace­
tone and acetaldehyde formed as intermediates during the
growth of fungus.
Dammann
found that Fusarium lini grown
on a 2# solution of dextrin produced carbon dioxide and ethyl
alcohol.
She reported no other products.
During an investigation of the specificity of the in­
tercellular globulin of Fusarium l i n i , Nelson^ found that
when the fungus was grown on a culture medium containing
carbohydrate in excess,
the growth yielded very little pr o­
tein and rapidly reached maturity and converted the excess
1.
2.
3.
4.
Anderson, A. K . , Morrow, C. A., and Willaman, J. J . ,
Minnesota Agr. Expt. S t a . , Ann. Rept. 1922, p. 35.
Willaman, J. J. and Letcher, Houston. Phytopathology
16, 941-49 (1926).
Dammann, Else. B e r . 7 1 B , 1865-68 (1938).
Nelson, Casper I., J. Agr. Research 4 6 , No. 2, 183-187
(1933).
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2
carbohydrate
into storage fats.
Such synthesis of fat was
followed by a considerable lag in the rate of growth.
When
the protein was extracted by grinding in a ball mill for
from 36 to 40 hours,
there was also extracted an oil which
when exposed to the atmosphere over a period of time became
a dark solid mass.
Solheim5 , on seeing this oil and the h a r ­
dened mass resulting from it, became interested in the syn­
thesis of the oil by the fungus and suggested this investiga­
tion in order to determine whether the oil produced by the
fungus,
in the conversion of the excess carbohydrate to a
fat, was a drying oil.
In view of this suggestion, this preliminary study was
undertaken to (l) find a method for extraction of the oil,
in a pure form, from the fungus and (2) to determine some
of the physical constants of the oil which might serve in
establishing the nature of the oil.
At this time, the author wishes to acknowledge grat e­
fully:
the advice and assistance of Dr. E. R. Schierz, under
whose direction this work was completed; the assistance of
Dr. W. G. Solheim in culturing and growing the fungus;
and
the grant-in-aid from the Research Committee of the U n i ­
versity with which some necessary apparatus was purchased.
5.
Solheim, W. G . , Head of Botany D e p t . , Univ.
(Private communication).
of Wyoming.
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Experimental
Growth of fungus:
The fungus was grown on a synthetic culture medium of
which the important consideration was the per cent carbo­
hydrate.
Several types of culture media were tried before
one was obtained that would give a satisfactory growth at
room temperature in a reasonable length of time,
in from 30 to 35 days.
that is,
Nelson^ found that if too little
carbohydrate was present the growth was feeble, however,
that when there was an excess of carbohydrate the fungus
rapidly reached maturity and converted the excess carbohydrate
into reserve stores of fat.
Rawlin's solution
7 Q
»
was found to give a good growth of fungus in about four
weeks when the carbohydrate concentration was £0 per cent
of the solution.
The Rawlin solution prepared for these
cultures contained the following ingredients in the quanti­
ties indicated in Table I.
Table I
Sucrose, C i g K g g O ^
Tartaric acid,
(CHOHCOgH)g
Ammonium nitrate,
(NH^NO-j.........
Ammonium phosphate,
6.
7.
8.
(NH^)gHPO^.....
300
grams
4
grams
4
grams
.60 grams
Nelson, op. c i t . , pp. 183-187.
Harshberger, John W . , A Tex t-Bo ok of Mycology and Plant
Pa th ol og y, p. 59£. P. Bl a k i s t o n ’s Son & Co., Philadelphia
(1917).
Smith, Erwin F . , Bacteria in Relation to Plant Diseases
Vol. I. p. 197. Carnegie Institution of Washington, Wash­
ington, D. C . , (1905).
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4
Potassium carbonate,
K C O
.60 grams
2 3
Magnesium carbonate, M g C O g . . ................ 40 grams
Ammonium sulfate,
Zinc sulfate,
( N H ^ ) g S O ^ H g O ) .......... 25 grams
Z n S O ^ H g O ) ^ ................... 07 grams
Ferrous sulfate, F e S O ^ H g O ) ^ ................ 07 grams
Potassium silicate, K _ S i O „ ............
2
6
07 grams
Distilled wa t e r ..........................
1500 cc.
The cultures were grown in Erlenmeyer flasks ranging in size
from 250 ml. to 2000 ml., the size of the flask having little
effect on the amount of growth obtained.
The cultures were
prepared by filling the flasks to a depth of about three
quarters of an inch with the culture medium, and then pl ac ­
ing them in an autoclave for treatment at a steam pressure
of 22 pounds for one-half hour.
After autoclaving the cul­
ture medium was inoculated with Fusarium lini transfered from
the stock by means of a sterile pipette*
Following the inoc­
ulation the flasks were loosely stoppered with sterile cotton
and placed on tables in a room in which the temperature varied
from 18 to 30 degrees centigrade, the usual temperature being
25°C.
During the period of incubation no attempt was made to
control the room temperature and the cultures remained und is­
turbed except for an occasional shaking which brought the
mycelium to the surface of the liquid medium.
After an incu­
bation period of from 30 to 35 days there was a considerable
lag in the rate of growth and it was considered complete.
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5
Preparation of fungus for extraction:
In the early experimental part of this work attempts
were made to extract the oil from the fungus immediately
after removing the growth from the culture medium and while
it was still moist.
In these trials, using either hot al­
cohol or ether as the solvent, much water and solid mater­
ial were extracted and it was found impossible to free the
oil from this mixture in a pure form or in a good yield.
Further experiments showed that it was necessary to dry the
fungus before extraction and if extracted when dry the oil
could be obtained free from water.
To dry the fungus,
the
growth was removed from the culture flasks and pressed as
dry as possible in a cheese cloth towel.
The fungus was
then placed in a large beaker and washed several times with
cold 95^ alcohol and then pressed dry in a cheese cloth
towel.
This process removed most of the surface water.
complete the drying operation,
vacuum desiccator,
To
the fungus was placed in a
containing anhydrous calcium chloride,
*
and carbon dioxide passed over it to replace the air in the
desiccator.
The desiccator was attached to a water aspir­
ator and evacuated to a pressure of 20 mm. Hg.
The drying
process required about one week and during this time it was
necessary to supply the desiccator with fresh calcium
chloride; when this was done the air was replaced with
carbon dioxide and the desiccator was evacuated from this
atmosphere.
The fungus was dried until crisp and then
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6
ground in a mortar to break
it up into small pieces.
Extraction of the oil from the funcus:
Of the solvents tried for extracting the oil,
anhydrous
ether that had been distilled over sodium was found to be
the most satisfactory.
Using ether as the solvent the oil
was obtained in good yield and almost free of solid mater­
ials.
The extraction of the oil from the dried fungus was
carried out in a Soxhlet extractor eauioped with glass .joints
and a flask of 500 ml. capacity for the solvent.
fungus was carefully weighed,
The dried
to the second decimal place,
into the porous paper extraction cup and placed in the ex­
tractor.
For the extraction,
ether was used.
about 400 ml. of the anhydrous
The apparatus was heated on an electric hot
plate.
Experiments were made to determine the extraction time
that would give the greatest percentage of oil.
These exper­
iments showed that the optimum extraction time was one hour.
This time was determined by discontinuing the extraction at
the end of an hour and removing the extract and adding a fresh
supply of solvent to the extraction flask.
was then continued another hour.
The extraction
When the solvent was evap­
orated from this second extraction it was found there had
been very little oil extracted and that the extract contained
a greater percentage of solid materials.
The effect of the
extraction time on the percentage by weight of oil extracted
is shown in Table II.
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7
Table
of Dried Fungus
II
Extraction Time
Wt. of Oil
Extracted
Per Cent
yield
206.63 g.
1/2 hour
11.66 g.
5. 64$
164.71 g.
3/4 hour
8.13 g.
4.93$
157.70 g.
1 hour
11.52 g.
7.30 $
199.45 g.
li? hours
15.73 g.
7.89 $
147.92 g.
lir hours
15.85 g.
10.72$
259.91 g.
1 hour
29.91 g.
11.50$
It was found that the solvent could be successfully re­
moved by distillation at diminished pressure.
The solution
was transfered from the extraction flask to a Claisen dis­
tillation flask of 250 ml.
capacity.
A boiling tube, drawn
out to a fine capillary, was inserted through the rubber
stopper in the neck of the flask.
This tube was then con­
nected with a tank of carbon dioxide by means of a rubber
tubing equipped with a pinch clamp.
The side arm of the
flask was closed with a rubber stopper carrying a glass
stop-cock.
The outlet tube of the flask was connected to a
water aspirator through a manometer.
of the solvent,
During the evaporation
a fine stream of carbon dioxide was allowed
to flow through the boiling tube thereby preventing any oxi­
dation of the oil and also the bumping of the solution as it
became more concentrated.
When the pressure became constant
at about 20 mm. H g . , as shown b y the manometer,
indicating
that the ether had been removed, heat was applied to the dis­
tillation flask, by means of an electric hot plate.
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The heat
8
melted the oil which had become solid during the evaporation,
and also removed the last traces of the solvent.
red,
The orange-
slightly viscous oil was transfered to a small weighed
glass-stoppered bottle.
It was preserved under an atmos­
phere of carbon dioxide and stored in a cool place, protected
from light.
All samples of oil were obtained and preserved
in the same manner.
The per cent yield of oil was calculated
as the ratio of the weight of oil extracted to the weight of
the dried fungus.
Determination of Some Physical Constants of the Oil:
In the determination of the constants, the official
methods of analysis for fats and oils as followed by the A s ­
sociation of Official Agricultural Chemists^ were adopted.
These methods will be referred to as the A.O.A.C. Methods
in the following pages.
In some cases it was found n e ce s­
sary to change the method slightly, particularly as to the
quantity of oil used in any one determination,
tity of oil available for analysis was limited.
starting the analyses,
as the quan­
Before
the six samples of oil were combined
in a flask and filtered through a hot water funnel,
accord­
ing to the A.O.A.C. Method'*'0 ’^ , to remove any suspended
9.
Official and Tentative Methods of Analysis of the Assoc­
iation of Official Agricultural Chemists, Fourth Edition,
1935, George Bant a Publishing Company (1936).
10. Ibid. , p. 404
11. Leach, Albert E., and Winton, Andrew L . , Food Inspection
and A n a l y s i s . Fourth Edition, p. 489.
John Wil ey and
Sons (1932).
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9
solid materials and to make certain that the oil was homo­
geneous.
The oil was collected in a previously weighed
glass-stoppered bottle and stored in a cool place protected
from light and air,
to prevent the oil from becoming rancid.
In determining the physical
constants all samples were trans-
fered directly from the stock flask.
The total weight of
the six combined samples was 79.9140 g.
1.
Determination of Specific Gravity at 25°/25°C.
The specific gravity of a substance is defined as the
ratio of the weight of a certain volume of a substance to
the weight of an equal volume of water at the same temper­
ature.
Following the A.O.A.C. Method^-2, the specific grav­
ity of the oil was determined at 25°C as related to water
at the same temperature.
A cleaned pycnometer,
filled with
recently boiled distilled water previously cooled to 20°C,
was placed in a constant temperature water bath at 25°C for
a period of thirty minutes.
At the end of this time,
the
level of the water was adjusted to the proper mark and the
pycnometer stoppered and removed from the water bath and
wiped dry.
After standing for thirty minutes the pycnometer
and water were weighed.
The weight of the water contained
at 25°C was ascertained by subtracting the weight of the
empty pycnometer from its weight when full.
For the determination of the specific gravity,
the pyc-
12. Official and Tentative Methods of Analysis of the Associa­
tion of Official Agricultural Ch em is ts , op. c i t . , p. 404
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10
nometer was filled with oil and treated in the same manner.
The weight of the oil at 25°C was found by subtracting the
weight of the empty pycnometer from its weight when filled
with oil.
Then the ratio of the weight of the oil to the
weight of the water gave the specific gravity at 25°C.
The
results from three trials gave an average value of 0.9118,
as shown in Table III.
Table III
Trial
2.
Wt. of Water
Wt.
of Oil
Specific Gravity 25°/25°C
I
9.4998
g.
8.6428
g.
0.9098
II
9.4954
g.
8.6734
g.
0.9134
III
9.5077
g.
8.6733
g.
0.9122
Refractive Index at 20°C.
For determining the refractive index of the oil a
Spencer Refractometer of the Abbe Type was used according
to the A.O.A.C. M e t h o d ^ .
The accuracy of the instrument
was checked against redistilled water, which has a refract­
ive index of 1.2998 at 2 0 ° C . , and against a calibrated
glass plate supplied with the instrument.
The temperature
of the instrument was maintained constant by a stream of
water circulated through the prisms.
reading,
Before taking the
the instrument and the sample were allowed to stand
for a few minutes in order that both would be at the temper­
ature indicated by the thermometer of the instrument.
The
13. Official and Tentative Methods of Analysis of the As soc ­
iation of Official Agricultural Chemists, op. c i t . . pp.
405-406.
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11
refractive index was found to be n^° 1.4680.
Table IV
Trial
I
3.
Refractive Index n ^
D
1.4679
II
1.4680
III
1.4681
IV
1.4680
Determination of Iodine Number (Hanus Method).
The iodine absorption number is the number of centi­
grams of iodine absorbed by 1 gram of a fat or oil.
This
constant is most valuable in identifying and differentiat­
ing oils and is based on the property of unsaturated fatty
acids to absorb a fixed amount of iodine.
In the determin­
ation of the iodine number by the Hanus method the procedure
as outlined in the A.O.A.C. M e t h o d ^ w a s followed.
The re­
agents were prepared and carefully standardized according
to the approved methods.
The determinations were run in quadruplicate in the fo l ­
lowing manner:
a sample of oil,
about 0.4 g . , was transfered
from a weighing pipette to a glass-stoppered 500 ml. bottle.
The exact weight of the transfered oil was found b y differ­
ence.
To the bottle was added 10 ml.
of chloroform,
to d i s ­
solve the oil, followed by 25 ml. of Hanus iodine solution
accurately measured from a burette.
This solution was al­
14. Official and Tentative Methods of Analysis of the As s o c ­
iation of Official Agricultural Che mi s ts . op. c i t . , pp.
410-412.
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12
lowed to stand for 30 minutes,
a uniform temperature.
by stop-watch,
in the dark at
At the end of this time, which must
be closely adhered to in order to obtain comparable results,
the stopper was carefully removed from the bottle and while
shaking the bottle 10 ml. of 15$ potassium iodide solution
was added and then 100 ml. of freshly boiled and cooled water.
The solution was titrated with standard sodium thiosulfate
solution using starch indicator.
Along with each determina­
tion a blank was prepared in the same manner except that the
oil was omitted.
From the data collected during the ti tra ­
tions of the determination and the blank, the iodine number
of the oil could be calculated from the following formula:
Iodine Number =
Q. In this formula A represents
the difference between the number of milliliters of sodium
thiosolfate used to titrate the blank and that used for the
determination; B represents the number of grams of iodine
equivalent to 1 ml. of the sodium thiosulfate solution;
C represents the weight of the oil in the sample.
and
The aver­
age iodine number of the oil, as calculated from the four
determinations, was 82.72.
The weights of the samples and
iodine numbers determined from them are shown in Table V.
Table V
Sample
Weight of Oil
Iodine Number
I
0.4878 g.
82.24
II
0.3549 g.
82.81
III
0.4654 g.
82.94
IV
0.3520 g.
82.88
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13
4.
Determination of Saponification Number (Koettstorfer
Number).
When treated with basic hydroxides,
glycerol and the salts of fatty acids.
soaps,
fats and oils yield
The latter are termed
and the process by which they are formed is called
saponification.
The amount of potassium or sodium hydroxide
that will react with a given amount of fat or oil in the pr o ­
cess of saponification will depend on the average length of
the constituent fatty-acid chains,
acid molecules,
for the smaller the fatty-
the greater could be their number in a given
amount of fat or oil.
Upon this principle is based a method
for determining the character of different fats and oils. The
saponification number is defined as the number of milligrams
of potassium hydroxide required to saponify one gram of fat.
In determining the saponification number of the oil,
the reagents were prepared and carefully standardized as
directed in the A.O.A.C. Method
15
that was followed.
The
determinations were run in quadruplicate in the following
manner:
a sample of oil (between 1 and 3 grams) was accurately
weighed into an Erlenmeyer flask of 250 ml. capacity.
Twenty-
five milliliters of alcoholic potassium hydroxide were added,
by pipette,
the flask connected to a water cooled condenser
and the solution boiled to saponify the oil.
two determinations,
In the first
the solutions were boiled for 30 minutes
15. Official and Tentative Methods of Analysis of the Assoc­
iation of Official Agricultural Chemists. op. c i t . , pp.
412-413.
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14
and in the last two the saponifying time was 45 minutes.
With each determination,
a blank was prepared in exactly
the same manner except that the oil was omitted.
After
the saponification was complete and the flask had cooled
to room temperature,
the determination and the blank were
titrated with standard hydrochloric acid using phenolphthalein for an indicator.
From the data collected during the
two titrations it was possible to calculate the saponifica­
tion number of the oil by the following formula:
Saponification Number =
In
formula
A represents the difference between the number of milli­
liters of alcoholic potassium hydroxide used to titrate the
blank and that used for the determination; B represents the
normality of the hydrochloric acid used in titrating;
C re­
presents the molecular weight of potassium hydroxide;
and
D represents the weight of the oil in the sample.
The ave­
rage saponification number of the oil, as calculated from
four determinations, was 192.7,
The weights of the sample
and the saponification number determined from them are shown
in Table VI.
Table VI
Sample
Weight of Oil
Saponification Number
I
1.3181 g
192.9
II
1.4352 g.
192.1
III
2.7277 g.
192.7
IV
3.0310 g
193.0
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15
5.
Per Cent Soluble Acids Calculated as Butyric Acid.
The per cents of soluble and insoluble acid were de­
termined on the same samples of oil as were used in the
third and fourth determinations of the saponification n u m ­
ber.
The per cent soluble acids was determined by the A.O.
A.C. Method
X6
as follows:
the flasks from the saponification
number determinations were placed on a water bath and the
alcohol evaporated.
Then to each flask was added a Qua n ­
tity of hydrochloric acid equivalent to the quantity of
potassium hydroxide used for the saponification of the sample
and 1 ml.- more (quantity of acid added I titration for blank titration for sample plus 1 ml.)
and the flask placed on a
steam bath until the separated fatty acids formed a clear
layer on the upper surface of the liquid.
The flask was
then filled to the neck with boiling distilled water and
cooled in an ice bath until the cake of fatty acids was thor­
oughly hardened.
The liquid contents of the flask,
contain­
ing the solid cake, was poured through a filter into a liter
flask and the flask refilled with boiling water and placed
on the steam bath until the fatty acids had again collected
at the surface.
three times,
This treatment with hot water was repeated
cooling and collecting the washings in the
liter flask after each treatment.
The combined washings
were titrated with standard potassium hydroxide using
16. Official and Tentative Methods of Analysis of the Associa­
tion of Off icial Agricultural Ch emists, op. c i t . , p. 413.
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16
phenolphthalein as an indicator.
A correction was made for
the additional 1 ml. of acid added and the milliequivalents
of potassium hydroxide neutralized by the soluble acid were
calculated.
Knowing the number of milliequivalents neutra­
lized it was possible.to calculate the equivalent weight of
the soluble acids as butyric acid.
By the ratio of the
weight of butyric acid to the weight of the sample was cal­
culated the per cent of soluble acid.
The results from two
determinations were 0.143$ and 0.206$.
6.
Hehner Number.
By the Hehner Number is meant,
uble acid in a fat or oil.
A.O.A.C, Method
17
the per cent of insol­
This value was determined by the
as a continuation of the preceding deter­
mination of the per cent soluble acids.
The flasks contain­
ing the cakes of insoluble fatty acids and the filter papers
through which the soluble acid had been filtered were al­
lowed to dry for 12 hours at room temperature.
of this time,
At the end
the cakes were transfered to weighed beakers
of 50 ml. capacity.
The solid acids that remained on the
filter papers were dissolved by pouring hot absolute alcohol
through the funnels.
The filtrates were collected in the
beaker containing the solid cake from the same sample.
The
beakers were placed on a steam bath to evaporate the alcohol
and then dried in an oven at 100°C.
to constant weight.
The
17. Official and Tentative Methods of Analysis of the Associa­
tion of Official Agricultural Chemists, o p . c i t . , p. 413.
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17
weights of the insoluble fatty acids in the beakers were
found by difference.
The Hehner Numbers for the samples
were calculated as the ratio of these weights to the
weights of the original samples.
The results for the two
determinations were 91,35 and 92.12.
7.
Acid Value.
The acid value is a measure of the amount of free fatty
acids in a fat or oil.
It is defined as the number of mill i­
grams of potassium hydroxide required to neutralize the free
fatty acids in one gram of fat or oil.
For this determina­
tion it was necessary to reduce the amount of oil used to
about one third the amount specified in the A . O . A . C ,
For the determination,
Method*^.
an accurately weighed sample of oil
(about 6 grams) was transfered to an Erlenmeyer fla.sk of
250 ml.
capacity.
To the flask was added 50 ml. of neu tra l­
ized 95^ ethyl alcohol and the flask shaken vigorously to
dissolve the oil.
Final solution was accomplished by the
addition of heat,
applied carefully to prevent esterifica-
tion of the fatty acids.
When the oil was completely dis­
solved, the solution was allowed to cool to room temperature
and titrated with standard potassium hydroxide solution u s ­
ing ohenolphthalein as an indicator.
The change in color
at the end point was gradual and indefinite,
therefore,
ough shaking during the titration was essential.
thor­
From the data
18. Official and Tentative Methods of Analysis of the A s so ci a­
tion of Official Agricultural Ch emi st s. op. c i t . , p. 417.
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission.
18
collected during the titration and knowing the concentration
of the standard potassium hydroxide it was possible to cal­
culate the number of milligrams of potassium hydroxide r e ­
quired to neutralize the free fatty acids in the sample.
The
ratio of the number of milligrams of potassium hydroxide to
the weight of the sample gave the acid value of the oil. The
average acid value, as calculated from two determinations,
was 2.810.
The weights of the oil in two samples,
and the
acid values determined from them are shown in Table VII.
Table VII
Sample
8.
Weight of Oil
Acid Value
I
6.6320 g.
2.818
II
6.4975 g.
2.803
Per Cent of Free Fatty Acid Calculated as Oleic Acid.
From the titration values obtained in the determination
of the acid value,
it was possible to calculate the per cent
of free fatty acid as oleic acid.
The number of milliequiv­
alents of potassium hydroxide required to neutralize the
free fatty acid was calculated and converted into the equiv­
alent weight calculated as oleic acid.
weight
of oleic acid to the weight
calculated the per cent
By the ratio of the
of oil
of free fatty acid.
values previously obtained,
in the sample was
For thetwo acid
these percentages were 1.416 and
1.408 respectively.
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Discussion of Results
From the character of the oil and the constants deter­
mined,
it was apparent that the oil extracted from Fusarium
lini was not the same oil as found by Nelson"^.
followed the normal
The oil
behavior of a non-drying o i l ^ ,
that is,
when exposed to the air and light for several days it became
colorless with little change in fluidity.
There was also a
change in the odor of the oil during exposure, however,
it
could not be said that the oil had become rancid during its
oxidation.
B y a comparison of the physical constants deter­
mined for the oil with those given in the International Crit­
ical T a b l e s ^ f o r fats and oils,
the placing of the oil as a
non-drying oil was substantiated.
It was found that the
physical constants determined for the oil compared most fav­
orably with the constants listed in the International Critical Tables
type.
22
for non-drying vegetable oils of the olive oil
A table showing some of the average physical c o n s t a n t ^
for non-drying vegetable oils and drying vegetable oils as
compared to the same constants determined for the oil extrac­
ted from Fusarium lini is given below.
19. Nelson, ojo. cit. , pp. 183-187.
20. A l l e n 1s Commercial Organic Analysis, Fourth Edition,
Vol. 2, p. 3. P. Blakiston's Son and Co. Philadelphia.
21. International Critical T a b l e s . I I , 196-217. McGrawHill Book Company, Inc., New York (1927).
22. Ibid. , p. 201.
23. Ibid. , pp. 201-203.
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20
Table VIII
Classification
of oil
Iodine
Number
Non-drying
vegetable oil
50-100
Oil from Fusarium lini
82.72
Drying vegetable oil
140-200
Saponification
Number
Hehner
Number
Acid Value
180-210
91-96
1-3
192>-7
91.75
2.81
190-210
91-98
2-12
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Summary
(1)
A method has been developed for the extraction of the
oil produced by Fusarium l i n i .
(2)
The following physical constants have been determined
for the oil:
1.
Specific Gravity at 350C / 2 5 ° C ...... . ........0.9118
2.
3.
Refractive Index n 2 0 .......................... 1.4680
D
Iodine N u m b e r .................................. 82.72
4.
Saponification N u m b e r ........................
5.
Per Cent Soluble Acids Calculated
192.7
as
Butyric A c i d ........................ 0.143# to 0.206#
6.
Hehner N u m b e r
91.35 and 92.12
7.
Acid V a l u e
2.818 and 2.803
8.
Per Cent Free Fatty Acid Calculated as
Oleic A c i d ....................... 1.416# and
(3)
1.4
0
The oil has been classified as a non-drying vegetable
oil of the olive oil type.
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BIBLIOGRAPHY
(20) A l l e n 1s Commercial Organic An aly si s, Fourth Edition,
Vol. II, P. Blakiston's Son & Co., Philadelphia (1910).
(1)
Anderson, A. K . , Morrow, A. C . , and Willaman, J. J. ,
Minnesota A g r . Expt. S t a . , Ann. R e p t . 1 9 2 2 , p. 35.
(3)
Dammann, Else, "Fermentation of Dextrin with Fusarium
Lini Bolley", Ber. 71B 1865-68 (1938).
(7)
Harshberger, John ff., A Text-Bo ok of Mycology and
Plant Pathology, P. Blakiston's Son & Co., Philadelphia (1917).
(21)
(22) (23) International Critical Tables of Numerical
Data, P h y s i c s . Chemistry and Technology. Vol. II, M c ­
Graw-Hill Book Company, New York (1927),
(11) Leach, Albert E . , and Winton, Andrew L . , Food Inspec­
tion and A n a l y s i s , Fourth Edition, John Wiley and Sons,
Inc., Ne w York (1932).
Morrow, Clarence A , , Biochemical Laboratory Methods,
John Wiley and Sons, Inc., New York (1927).
(4) (6) (19) Nelson, Casper I., "A Method of Determining
the Specificity of the Intercellular Globulin of F u s ­
arium Lini", Jj_ Agr. Research 46 No. 2 183-87 (1933).
(9)
(10) (12) (13) (14) (15) (16) (17) (18) Official and
Tentative Methods of Analysis of the Association of
Official Agricultural C h e m i s t s . Fourth Edition, 1935,
George Banta Publishing Company, Menasha, Wis. (1936).
(8)
Smith, Edwin F . , Bacteria in Relation to Plant D i s ­
eases . Vol. I, Carnegie Institution of Washington,
Washington, D. C. (1905).
(2)
Willaman, J. J . , and Letcher, Houston, "Biochemistry of
Plant Diseases: VIII Alcoholic Fermentation of Fusarium
Lini", Phytopathology 16 941-49 (1926).
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission.
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