STUDiES
ON
INTESTINAL
DIGESTION
OF STARCH
IN MAN.
II. INTESTINAL
HYDROLYSIS
OF AMYLOPECTIN
IN
INFANTS
AND
CHILDREN
Salvatore Auricchio, M.D., Domenico Della Pietra, M.D., and Angela Vegnente, M.D.
Istituto di PueriCultura della University of Naples. Gruppo di ricerca del CNR sulla fisiologia e patologia dell’apparato digerente, Naples, Italy
MATERIAL AND METHODS
853
STARCH is a mixture of two different
poly-glucoses, amylose and amylopectin.
Amylose has a linear structure and is
corn-posed of glucose units whicil are linked by
1,4 giucosidic bonds (maltose units).
Amy-101)ectin has a branched structure similar
to glycogen; in amylopectin the majority of the glucose units are connected by 1,4r glucosidic bonds (maltose units), but there
are also 1,6 glucosidic bonds at the branch Ioints (isomaltose units).
Starch is digested into glucose by
sali-vary and pancreatic amylases and by the
glucosidases of intestinal mucosa.
In vitro the amylase of human saliva
ilydrolyzes amylose into maltose and maltotriose rapidly,1 and maltotriose into
glucose and maltose very siowly.2I Ill vitro
the same enzyme splits amylopectin into
glucose, maltose, maltotriose, and a mixture of branched dextrins,3 tile smallest being
a tetraglucose.9
In the human intestinal mucosa five mal-tases (one of which also has isomaltase acti-vity)’1’ 12 and one glucoamylase’3 were
iden-tified; tile further hydrolysis into glucose
of tile products of tile a-amylolysis of
starch in civo is probably due to the acti-vity of these mucosal glucosidases.
There is only one study on intestinal
di-gestion of starch in man in vivo. After a
test meal containing soluble starch the
average number of glucose units of
intes-tinal carbohydrates was measured in three adults and found to range between 2.1 and
2.4.14
The present report describes studies on
the carbohydrates which accumulate in the duodenum of normal infants aild small
children after a test meal containing amy-lopectm.
Subjects
Nine normal infants and four normal small
children between 23 and 28 months were
studied. The infants were artificially fed
with powdered milk to which
dextri-mal-tose and, from the beginning of the fourth
montil, 4 gm of flour per kg of body weight
were added. Starchy foods were given from
the end of the fourth montil.
A 26-month-old child, D.F., affected by
exudative enteropathy of unknown etiology
and successfully treated the last 3 months by prednisolone, was also examined.
Composition of the Test Meal
The test meal contained amylopectin
(about 9 gm/100 ml), casein (4 gm/100 ml),
and vegetable oil (4 gm/100 ml) and is
pre-pared by dissolving, without heat, 50 gm of amylopectin in 500 ml of water by shaking for 60 minutes. The amylopectin solution is centrifuged and the sediment discarded. The supernatant contained about 90 mg/mi
of carbohydrate, measured as glucose after acid hydrolysis. Casein was dissolved in the
amylopectin solution by shaking for 90 minutes. Just before administration
vegeta-ble oil was added slowly to the test meal
under homogenization with the Ultra Tur-rax; then the meal was further
homoge-nized for 30 minutes.
In the present paper tile carbohydrate
content is expressed as glucose, which was
obtained after hydrolysis of the polysac-charide or oligosaccharides.
Intubation Technique and Sampling
The test meal (500 ml/m2) was given by a tube situated in the stomacil, when tile
(Submitted November 10, 1966; revision accepted for publication January 10, 1967.)
ADDRESS: (S.A.) Istituto di Pucricultura della Universit#{224} di Napoli. Via Annunziata .34, Napoli, Italy.
subjects had fasted for 10 to 12 hours;
dur-ing this time water was given ad libitiim.
The duodenal juice was continuously
sam-pled for 2 to 4 hours after the test meal by a rubber tube
(
internal diameter 2 mm)
sit-uated at tile end of tile duodenum; thep0-sitioll of tile tube was cilecked by
radiogra-pily.
In order to prevent furtiler hydrolysis of
the carbohydrate during the collection, the juice was directly collected into a vessel
maintained Ill a freezing solution of dry ice and acetolle.
The duodenal juice was then rapidly
ho-mogenized at 4#{176}C.After withdrawing a
sample for assay of amylase activity, tile
rest was heated at 100#{176}Cfor 5 minutes to
inactivate the amylase.
Assay of Amylase Activity
The amylase activity was determined
ac-cording to the method of Dahiqvist’3-incu-bation time at 37#{176}C:30 minutes. Olle unit of amylase activity liberates reducing
groups corresponding to 1 smole of
mal-tose/minute.
Determination of Average Degree
of Polymerization
The duodenal juice after ileating was
used for: (1) determination of tile total car-bohydrates after hydrolysis of dextrins into
glucose (expressed as mole of glucose), (2)
determination of tile reducing power before
hydrolysis, compared with a standard
mal-tose curve (expressed as mole of maltose).
The ratio between a and b is the average
degree of polymerization (average DP), of the intestinal carbohydrates.”
Determination of the Total Carbohydrates as Glucose Liberated by Hydrolysis
The heated juice was deproteillized in either of two ways:
1. By tungstic acid’T-l ml of duodenal juice was added with 1 ml of 10% sodium
tungstate and 8 ml of 1/.,N sulfuric acid.
After 30 minutes at 4#{176}C,the mixture was
centrifuged at 27,000 g for 10 minutes. The
sediment was washed with 8 ml of ‘jN
sul-furic acid and centrifuged. The
superna-tants were combined, neutralized with NaOH (phenolphthaiein),’5 and diluted
vith water to 25 ml.
2. By chloroform’-1 ml of duodenal
juice was added with 0.25 ml of chloroform
and 0.1 ml of amyl alcohol and tile mixture
was silaken at 4#{176}Cfor 30 minutes, then centrifuged at 3,000 g for 60 minutes. The
chloroform layer containmg the proteins
was washed twice with 1 ml of water; then,
the aqueous layers were combined and
once more deproteinized with chloroform.
The small amounts of chloroform present in
the aqueous solution were eliminated by
evaporation under diminished pressure at
60#{176}Cafter neutralization with NaOH (piie-noipilthalem
)
. The deproteinized solutiollwas then diluted with water to 25 ml.
After deproteinization
by tungstic
acid
orchioroform the carbohydrates were
hydro-lyzed into glucose
by
sulfuric
acid,’8
for
2 ilOurs. The liberated glucose was
inca-sured as reducing po’er by tile titrirnetric
methods of Somogyi2#{176} or Shaffer and Hartmann;21 ill the latter method glucose
(
60 mg/i) was added to tile reagent.22 Ill some experiments the total carbohy-drates were also determined by two othermethods, in which the duodenal juice was
deproteinized after enzymatic hydrolysis of
the carbohydrates. In one method the
oligo-saccharides were first directly hydrolyzed
into glucose by the glucoamylase of
Rhizo-pus Deiemar, and then the glucose was
de-termined with the glucose oxidase reagent
after deproteinization
by Zn( OH
)2.23 In theother method the oligosaccharides were
first hydrolyzed by pancreatic amylase,
then deproteinized by phosphotungstic acid
and Ilydrolyzed into glucose by hydrochloric
acid; tile glucose was determined with the
glucose oxidase reagent.232’
Determination of the Reducing Power of Intestinal Carbohydrates Before
Hydrolysis
After deproteinization of the duodenal
juice by tungstic acid’ or chioroforml9 the
determined by titrimetric methods2o22 and
compared with a standard maltose curve.16
Tile lleatnlg time with the reagent was 60
minutes in order to develop full reducing power.’
Ill some exl)erinlents tile reducing power
was measured without deproteinization with tile 3: 5-dinitrosalicylate 14
Fractionation of the Carbohydrates
in Duodenal Juice
The carbohydrates of duodenal juice
were first fractionated by gel filtration on
Sephadex G 50;” the oligosaccharides with
an average DP less than 7 were further
sep-arated by cilromatography on charcoal
ccl-ite column.
GEL FILTRATION ON SEPHADEX G 50: The duodenal juice was deproteinized first by
tungstic acid’7 and tilen by chloroform’’.
The neutralized solution, which contains
about 1.5-2.5 gm of total carbohydrates,
was concentrated to 25 ml under
dimin-isiledi pressure at 60#{176}C.After centrifugation
tile salllple was applied to a Sephadex C
50 column (3 x 125 cm) and tile
chromato-gram developed Witil water. Flow rate was
about 60 mi/hour. Volume of each fraction
\V15 5 ml.
In order to determine tile average DP of
the carbohydrates in the chromatographic
fractions total carhoilydrates were mea-sured by phenol-sulfuric acid2 and
reduc-ing power by tue colorimetric reagent of
Sornogyi-Nelson (heating time 60 minutes;
maltose standard curve).TT
The fractions containing carbohydrates
Vitil an average DP less than 7 were com-bined, concentrated to 20 to 25 ml under diminished pressure at 60#{176}Cand then uti-lized for charcoal chromatography.
CHARCOAL-CELITE CHROMATOGRAPHY: Tile charcoal-cehte column (4.2 x 25 cm) was pre-pared according to Whistler and BeMiller.25
Ciucose was eiuted with water and the
oligosaccharides (DP from 2 to 5) with a
gradient water-ethanol 30% (mixing chamber
4 liters); the coiumll Va5 tilen wasiled with 50% etilanol in order to elute larger dextrins.6 Volume of eacil fraction was 20 ml. The rate
of flow through tile column was kept at
about 80 mi/hour by applying air pressure with a micropump.
The separated oiigosaccilarides were
iden-tified by tile following methods:
1. Measurement of tile DP.’6 Acid
ily-drolysis for 120 minutes was found to be
sufficient to give complete hydrolysis of
oh-gosaccharides into glucose.
2. Co-chromatography with known
mate-rials, on Whatman no I. paper, in the
fol-lowing solvents
(
descending technique):ethylacetate-pyridine-vater
(
10:4:3 byvol-ume
)
and hutanol-pyridine-water(
6:4:3 byvolume
)
. Silver nitrate-sodium hydroxidereagent was used for location of
ohigosac-charides.8
3. Ieasurement of tile partition function
21 by using the multiple descending paper
chromatograpily
(
solvents as above)
.The maltotetraose was also identified by
a-amyloiysis with human saiiva.
Reagents
Amylopectin powder
(
M.W. over1,000,000
)
and cehite 535 were obtained from Koch-Ligilt Lab. Casein whitesolu-ble, for nutritional experiments, activated
charcoal powder for decoiorizing purposes, and glucose (micro-analytical reagent) were
obtained from British Drug Houses. Mal-tose monohydrate puriss and pancreas
-Amylase (Pancreatin) were obtained from Fluka.
Maltotriose, maltotetraose, maltopentaose,
and maitohexaose were a gift of Prof. %V.
J.
Whelan (London); isomaltose, isomal-totriose, and panose were a gift of Dr. A.Jeanes (Peoria, Illinois) and of Dr. S. C. Pan
(New Brunswick, New Jersey).
Giucoamy-lase from Rhizopus deiemar (Sumizyme;
Shim Nihon Chemical Co., Japan) was a
gift of Equitra (Brussels).
Sephadex C 50 was obtained from Phar-macia.
RESULTS
(av-856
TABLE I
AVERAGE DP OF CARBOHYDRATES OF DUODENAL
JuIcE AFTER A TEST MEAL CONTAINING
ASIYI.oI’Ec’rIN
After Deproleinizalion lfter Dejirolein ization
by Tungstic Acid by Chloroform
11.15
9
8.4
6.17
6
.)
3.5
3.3 2.92
11.05
8.9.5
8.1.5
6.3
6
I
5
3.6
3.30 2.9-2
erage value 140 ml
)
. The recovery of thecarbohydrates of the test meal from the du-odenum ranged betvveen 20 and 77%
(
aver-age value 51%).
The deproteinization of intestinal juice
by tungstic acid or chloroform produced no
significant loss of oligosaccharides or
poly-saccharides, as demonstrated from the fol-lowing observations:
1. The recovery of amylopectin from the meal is about 90% with the two deproteiniza-tion methods.
2. The recovery from the meal and from
the duodenal juice of oligosaccharides with
an average DP equal to 5
(
prepared in vitroby z-amylolysis of amylopectin
)
is about95% with both deproteinization methods. 3. The average DP of intestinal contents
is the same if measured after tungstic acid
or chloroform deproteinization
(
see Table I).4. The total carbohydrate content of du-odenah juice is about the same if the
hydrol-ysis of dextrins into glucose is done before or after deproteinization (see Table II).
5. The reducing power of intestinal car-bohydrates with an average DP
=
3 is the same if measured without deproteinization by the 3:5-dinitrosalyciiate reagent14 orafter deproteinization with tungstic acid or chloroform by titrimetric methods.
The duodenal juice collected before the test meal and deproteinized by tungstic
acid or chloroform contains only trace amounts of reducing substances, both
be-fore and after acid ilydrolysis by sulfuric
acid.
The -amylase activity and tile average
degree of polymerization of the
carbohy-drates of duodenal juice after tile test meal
containing amylopectin in infants and small
children are reported in Table III. In most small infants
(
between 2% and 6 months of age)
the average DP is high and the2-amy-iase activity is low; only in case No. 5 is
there an average DP equal to 3.15; in tile other subjects the average DP ranges
be-tween 5 and 9. In all older normal infants
and in small children (between 10 and 28
months of age
)
the 2-amyiase activity is high and the average DP is correspondinglylow, ranging between 2.6 and 3.6. In the
26-month-old child with exudative enterop-athy treated with prednisolone the
2-amy-lase activity is very iligh, 366 U/mi, and the
average DP is very low (only 2.2). In order to identify the carbohydrates which are present in tile intestinal juice, tile duodenal dextrins were fractionated by gel
filtration and then by cilarcoal
chromatog-raphy in 5 subjects, with varying velocities
TABLE II
TOTAI CARBOhYDRATES OF DUODENAL JUICE AFTER A
TEST MEAL CONTAINING AMYLOPECTIN IN 4 SUBJECTS
-MEASUREMENT BY DIFFERENT METhODS
ing glucose/mi
Method
Case No. 1 Case No. 2 Case No. 6 Case No. 8
1
2
3
4
68.2
63
68
61.5
42.8
42
47
44
54
53
50
54.4
70.7
66 67 67.2
Method 1-deproteinization by tungstic acid + sul-furic acid hydrolysis + titrimetric measurement of
glu-cose.
Method 2-deproteinizationby chloroform + sulfuric
acid hydrolysis + titrimetric measurement of glucose. Method 3-a-ainylolysis + deproteinization by
phos-photungstic acid + hydrochloric acid hydrolysis +
glu-cose oxidase method.
Method 4-Glucoamylolysis +deprotciiization by
18
1#{128}
14
ii
8
E
4
E
0
(D
250 300 400 800 700 800
Ftc. 1. Separation by gel filtration on Sephadex C 50 of the carbohydrates present in duodenal juice after a test meal containing amylopectin-No. 4,
age 5 months. The average DP of some fractions is also reported.
a DP lower than 7 were further separated by
charcoal chromatography (Fig. 2). By this
method a good separation of glucose and
linear oligosaccharides (maltose to
malto-pentaose) was obtained. Other dextrins,
TABLE III
TOTAL CARBOHYDRATES, THEIR AVERAGE DEGREE OF
POLYMERIZATION AND AMYLASE ACTIVITY OF DUODENAL
JuicE OF INFANTS AND SMALL CHILDREN AFTER A
TEST MEAL CONTAINING AMYLOPECTIN
of 2-amyioiysis. Tile recovery of the carbo-hydrates from the Sephadex and charcoal
columns is satisfactory and the average DP of the recovered carbohydrates is practical-ly unchanged (see Tables IV and V ); there-fore, the results are given in percentage of
recovered material.
The gel filtration on Sephadex C 50 sepa-rated dextrins with an average DP larger
than 7 from dextrins with an average DP
smaller than 7
(
Fig. 1)
. The former weresubdivided into six groups of decreasing DP
(
see Table IV)
. In the subject with thelow-est average DP of total carbohydrates in
duodenal juice
(
No. 14)
there are no dex-trins larger than 30 glucose units. There aretrace amounts of dextrins larger than 15
glu-cose units, and large amounts of smaller
car-bohydrates. In the other subjects with
higher average DP of total carbohydrates in duodenai juice, there are correspondingly
larger amounts of large dextrins and
small-er amounts of ohigosaccharides; in the
3-month-old infant (No. 3) with an average
DP of total carbohydrates as high as 8.2,
29% of the dextrins are larger than 100 glu-cose units and only 34% of the dextrins are
smaller than 7 glucose units.
In four subjects the oligosaccharides with
(‘axe
Number
3 4
8
9 10
11
12 13 14 (D.F.)
Age
(1111))
21
3 3
5
6
6
6 10
12
19
21
25
28
26
Total Carbo-hydrates (mg/mi)
68
44 47
63 71
52
79 68
60 54
74
45
56
34
Average
DP
6.7
8.95 8.2
., 3.15 9 6.0
3.6
3.32
2.92
3.05
2.69
2.2
1my! axe Activity
(7in1
7.65
5.3 3.9 6.2 38
8.2
18.2
48
87
53
64 72.5
366 0P26
WaPer - ethanol 30 % ethanol 50%
hiera
Fic. 2. Separation by charcoal chromatography of glucose and oligosac-charides present in duodenal juice after a test meal containing amylopectin -No. 4, age 5 months. The glucose was first eluted with water; then, the
linear oligosaccharides from maltose to maltopentaose were eluted with gradient water-ethanol 30%. The column was then washed with 50% ethanol
in order to elute low Rf oligosaccharides.
which are probably branched
(
DP between 4 and 7), were not separated from each other.The pattern of small ohigosaccharides differs according to the value of average
DP of total carbohydrates in duodenal
juice. In the subject with a very low
aver-age DP
(
No. 14)
there were small amountsof glucose; maltose and maitotriose to-gether make up as much as 70% of total carbohydrates, with a molar ratio maltose:
maltotriose equal to 3.5:1. In the other sub-jects with less complete hydrolysis of amy-lopectm, there were correspondingly small-er amounts of glucose and maltose and
larger amounts of maltotetraose; maltopen-taose is also present in No. 3 and No. 4.
(see Table V).
In case No. 14, with a very low average
DP of total carbohydrates of intestinal
juice, about 5% of the dextrins have an av-erage DP equal to 4.13. These dextrins are resolved by paper chromatography in two different spots, with a low Rf (lower than the Rf of the maltohexaose); these are
prob-ably branched dextrins formed by 4 and 5 glucose units. These compounds are not de-tectable in the other subjects with less com-plete digestion of amylopectin. In all cases small amounts of ohigosaccharides with a
very low Rf on paper and average DP
rang-ing from 5.5 to 7.2 are eluted from charcoal
by 50% ethanol; these are probably larger branched dextrins.
COMMENT
In infants at the end of the first year of
life and in small children the a-amylase activity of duodenal juice after a test meal containing amyiopectin is high and the in-testinal hydrolysis of starch in vivo is very
rapid. The amylopectin, composed of more than 5,000 glucose units, is digested at the end of the duodenum into carbohydrates with an average DP equal to about 3. In
adults we found intestinal digestion of the
amylopectin to proceed at about the same
velocity.
Sixty to seventy percent of the total car-bohydrates are represented by maltose and
maltotriose; the human saliva a-amyiase,
which has no maltase activity,30 can
hydro-lyze maitotriose very slowly in vitro.24
Therefore, both maltose and maltotriose have to be considered limit compounds of
the a-amyloiysis in vivo. In pigs and rats
the intestinal hydrolysis of maltotriose is
malto-TABLE IV
DEXTRINS OF I)IFFERENT DP PRESENT IN DUODENAL JUICE AFTER A TEST MEAL CONTAINING AMYLOPECTIN AND SEPARATED BY GEL FILTRATION ON SEPHADEX G 50
Dextrins of Different DP ->100 100-40 40-30 30-20 20-15 15- 7 <7
(‘axe No. .3
--
Case No. 7( C DP
(‘axe No. 4
-% DP
(‘axe No. 10 (‘ase No. 1
(D.F.)
)c DP % DP
29 19 7.45 3.72 2.45 4.45 34 130 66 32 22.5 17.1 10.4 2.96 19 21.5 2.5 7.7 1.6 48.5 117 60.5 33.5 25.6 17.1 3.08 8.7 15.1 12.7 5.8 0 6.3 51.5 108 0 71.5 0 38 6.3 22.4 6.5 12.3 12 3.66 2.86 71.5 37 -18.7 8.1 ‘2.32 0 0 0 1.15 1.9 15.5 9.8 8.34 87.5 2.04 2.2 2.2 94.2% DP of total
carbohy-drates of duodenal
juice
DP of recovered
carbohydrates Recovery from the
column 8.2 7.85 92.5% 6 5.95 97.7% 5 5 96.7% 3.3 3.3 92%
* Results expressed for each group of dextrins as percentages of recovered carbohydrates.
t l)P=average I)P of each group of dextrin.
TABLE V
OuGos.tCcIIARIDEs AND GIucosE IRESENT IN I)C0DENAL JUICE AFTER A TEST MEAL CONTAINING AIIYL0I’EcTIN AND SEPARATED BY CHARCOAL ClIuoMAToIt.PhIY*
Dextrins
(‘axe No. .1 Case No. 4 (axe No. 10 Case No. 14 (D.F.)
%t DP % DP % DP % DP
Glucose
Maltose Matotriose
Mahtotetraose
Maltopentaose
Low Rf
Ohigosac-charides
Low Rf Ohigosac-charides 0.007 8.7 10.5 10.7 1.47 2.13 2.85 3.97 4.85 7.2 1.07 16.6 16.9 11.7 1.1 3.67 2.94 4.17 4.9 7.2 2.46 39.8 22.2 3.27 0 2.46 2.94 3.94 6 6.75 50.2 21.3 1.32 0 5.12 2.38 3 3.94 4.13 5.55
DP of total carl)o-hydrates*
DP of recovered
carbohydrates Recovered from the
column 2.96 2.96 86% 2.86 2.81 94.5% 2.3 2.25 88.7% 2.04 2.15 80%
* These ohigosacchiarides were separated by gel filtration as a group of dextrins with a DP<7 (see Table IV). t Results expressed as percentage of recovered carbohydrates from the Sephadex column.
These ohigosaccharides were eluted by water-ethanol 30% like the linear oligosaccharides from maltose to inaltopentaose.
tetraose; larger amounts of this oiigosac-charide have been found in smaller infants, who have lower levels of a-amylase
acti-vity. This suggests that the in vivo hydroly-sis of maltotetraose is probably due to
sali-vary and pancreatic amylase.
The a-amylolysis of amyiose, which is random in the early stages of hydrolysis,
becomes more selective in the further digestion of the smaller linear liberated ohigosaccharides, in consequence of the
greater resistance to enzymatic attack of the two bonds nearer to the non-reducing end and of the bond near the reducing
2, 3, 30. 32-34 J vitro human saliva
a-amylase hydrolyzes maitotetraose more rapidly than maltotriose and more slowly than larger linear ohigosaccharides.3#{176}32 This woul(I explain the presence of large amounts of maltotetraose in the duodenum of infants with lower levels of a-amylase
activity; at higher levels of a-amylase this
enzyme splits maltotetraose into maltose and small amounts of glucose and
malto-triose.2’
Isomaltose was not found in duodenal juice after a test meal containing amylo-pectin; the smallest ohigosaccharide con-taming one 1, 6 bond liberated in vitro from amylopectin by human salivary a-amylase
is not isomaltose,’ but a tetragliicose.#{176} This
and other larger branched dextrins58 are
probably the in vivo substrates of the mucosal “isomaltase” and glucoamylase
activities.
In most infants 6 months old or younger
the intestinal hydrolysis of amylopectin in the duodenum is incomplete, with large amounts of dextrins composed of more tilan 30 glucose units and, in the small oh-gosaccharides group, a decrease in the glu-cose and maltose content as well as an increase in the maltotetraose content.
The incomplete digestion of amylopectin
is a consequence of the low levels of
a-amy-lase activity in duodenal juice after the
meal; on the contrary, the mucosal
a-di-saccharidases, with the single exception of maltase 1, are already present at adult levels in the newborn.
It is to be expected that the incomplete
2-amyioiysis of starch in the duodellum
would give a relatively high frequency of starch malabsorption in the first year of life, because in this age group the intestine
probably has little reserve capacity for the digestion of starch.
The results of this study can also help elucidate the pathogenesis of starch
mal-absorption in congenital sucrase and iso-maltase deficiency.36 In normal conditions
the mucosal “disaccharidases” have to hy-drolyze in the digestion of starch not only maltose, but also maltotriose and branched
dextrins. In pigs and rats maltotriose is
hy-drolyzed by mucosal giucosidases more slowly than maltose.31 In congenital sucrase and isomaitase deficiency the remaining “maltase” activity can be sufficient to hy-drohyze maltose, but not maltotriose. One can suppose that in this disease starch mal-absorption is probably due to malabsorp-tion of maltotriose and branched dextrins.
SUMMARY
In 14 infants and small children the (I
-amylase activity and the carbohydrates of
duodenal juice were studied after a test meal containing amyiopectin.
In infants at the end of the first year of life and in small children the amyhopectin
is very rapidly hydrolyzed into glucose,
maltose, maltotriose, and branched dex-trins; these compounds are probably hydro-lyzed into glucose by the action of mucosal glucosidases.
In infants 6 months old or younger the intestinal hydrolysis of amylopectin in the intestine is incomplete, with large amounts of dextrins containing more than 30
glu-cose units and, in the small ohigosaccharides group, a decrease in the glucose and mal-tose content as well as an increase in the maltotetraose content.
The analysis of carbohydrates which ac-cumulate in intestinal lumen during diges-tion of starch will be of value in studying pathogenesis of starch maiabsorption.
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Acknowledgment
The authors are indebted to Dr. D. H. Brown
(Department of Biological Chemistry, Washington University School of Medicine, Saint Louis,
Mis-souri); Dr. K. C. de Noord (Avebe, Veendani, holland), Dr. A. Jeanes (U. S. Department of Agriculture, Peoria, Illinois), Prof. H. Neukom
(Agrikulturchemisches Institut, ETH, Zurich,
Switzerland), Dr. S. C. Pan (The Squibb Institute, New Brunswick, New jersey), and Prof. W. J.
Whelan (Department of Biochemistry, University
of London, London, England) for valuable advice
and generous gift of oligosaccharides. The authors are also indebted to Equitra (37, Rue de Ia Loi,
Bruxelles, Belgique) for the gift of glucoamylase
and to Miss Anna Norton for helping in the
prepa-ration of the manuscript.
AN UNUSUAL DISEASE OF THE NEWBORN DESCRIBED IN 1785
Almost two centuries ago Dr. Bassignot described an unusual skin disease of
new-born infants in these words:1
Seyne or Sedna, a small town in Provence is the
theatre of a very peculiar disease, which attacks
almost all the new born infants at that place. Some authors have spoken of it under the name of crinons or comedons; but it is known by the people of the country under the name of cees, a corruption of
ceddes, a provincial term which signifies a bristle.
It sometimes manifests itself within the space of
twelve hours, sometimes. however, not till the end of fifteen (lays, or even a month.
The symptoms by which this disease is known, are a very considerable itching, which is augmented by the heat of the bed, and prevents the infant from
sleeping; a perpetual agitation; an inability to suck, the child’s tongue not being able to accommodate
itself to the nipple; and, at last, the noise of its cries being diminished, which become hoarse, and are indeed almost extinguished. This last sign appears to be the most certain; and they in general judge of the severity of the disease by the degree to which the voice is extinguished, and by the weakness of the cries of the infant.
When, by these signs, the disease is known to be
present, they proceed immediately to the cure. This
consists in frictions, which are performed b the
women of the country, and who are so much in the
habit of treating this disease, that they do not in
general call in the aid of any medical practitioner.
These frictions are performed on different parts of the body, according to the state of the disease that is present. And the distinguish these stages of it,
which are sometimes very distinct, sometimes united.
Ill the first, the diminution of the noise in crying
is conjoined with a total incapability of sucking. This re(juired friction at the upper part of the ster-num, on the fore and back parts of the neck, on the cheeks towards the angle of the inferior jaw, and on the temples. In the second state of the disease, the infant still enjoys a certain facility in moving tile
tongue, without, however, being able properly to
seize the nipple; when the arms are set at liberty they are extended, the fingers are spread out with a
considerable degree of tension, or the hand is firmly
clenched. This state requires friction of the fore-arm,
from the shoulder to the wrist. The third stage is
distinguished merely by a diminution of the cries;
then frictions are directed to the arms, the shoulders, the back, and even to the calves of the legs; which
probably, as well as the hands, demonstrate the exis-tence of crinons in these parts, by some particular
movement, but which has not vet been sufficiently
attended to.
NOTED BY T. E. C., Jn., M.D.
REFERENCE
1. Bassignot, NI.: History of the disease known aS crinons which attacks the newborn infants of
