Tech. Bull.. Fac. Agr. Kagawa Univ..
STUDIES
ON LEGUME STARCHES
VIII
A
Note on the X-Ray Diffractometric Study
Sin'itirB
KAWAMURA
(Laboratory of Biological Chemistry)
and
Susumu
HIZUKURI
'"(Received ,June 20, 1959)
Microscopic observations on legume-star ch gr anules(l) and viscosity behaviors of legume star ched2) were reported in English a s Parts I and I1 of this series P a r t s 111-VI concerning t h e separation and determination of amylose and amylopectin of legume starches were reported in Japanese by KAWAMURA and TADA(~-') K A W A M U R A ( ~ made a summarizing discussion a s Part VII, of which mention will be made below
Here a brief report is made on t h e result of experiments with a n X-ray diffractometer on some legume starches
X-ray diffraction studies on starches were thoroughly discussed by FuwA(') in 1951 (supple- mented by MURAKAMI('O) in 1955) Recently an X-ray diffractometer has come into u s e T h i s apparatus can overcome the defects of t h e former photographic method, and enables to obtain more detailed data easily HIZUKURI and NIKUNI(~'-'~) applied this apparatus to t h e studies of starches
Generally t h e DEBYE-SCHERRER patierns of starches a r e classified into type A (cereal), type
B
( t u b e r ) , and type C (intermediate) Type A i s represented by t h e corn starch and type B by t h e potato starch According t o NIKUNI, F u w n , and T A T S U M I ' ~ ~ ' t h e X-ray diffraction patterns change contin~~ously from type A to type B in t h e following order: corn (A), cassava, Fagopyrum esculentum,wheat, rice, adzuki bean, sweet potato, Dioscolza batatas, Nelun~bium nucifirum, Lycorzs radzala, Scilla thunbergii, Lilium auratum, Tulipa gesnerzana, Er) thronrum japonzcum, and potato (B)
EXPERIMENTAL
SAMPLE STARCHES Starches were prepared from t h e following five legume seeds : Kcia faba
(broad bean), Phassolus aureus (mung or green gram), P h vulgaris (kidney bean, form kintaki), D~lzchos lablab (hyacinth bean), and Canaualza gladiata (sword bean). T h e pulverized seeds were soaked in water and treated with a n electric mixer T h e supernatant solution was removed and t h e starch-rich precipitate was washed with water, sieved, and treated with 0 2% sodium hydroxide t o remove proteinaceous impurities T h e stalch thus obtained was further well washed and dried T h e starch was subjected t o diffractometry in t h e s t a t e of 20-23% moisture content
APPARATUS A N D PROCEDURE They a r e t h e same a s reported by HIZUKURI and N I K U N I ( ~ ~ ) A
"Norelco" X-ray diillactometer oL t h e North American Phillips Co was used a t t h e Faculty of Science, Osaka University T h e conditions were a s follows: high-tension voltage 30 kV, current 15 mA, scale factor 4, multiplier 1, time constant 8 sec, divergence slit l o , receiving slit 0 006 in, scatter slit l o , scanning speed
0
5'/min; X-rays, nickel-filtered copper radiationRESULI T h e result i s shown in Fig 1 T n u s mung starch belonged to type A, and other starches belonged to type C All these other starches of type C were nearer t o type A rather than t o type B According to t h e result reported by HIZUKURI and N I K U N I ~ ' ~ ) mung starch showed a faint ring 1, which could not be noted i n t h e present mung-starch sample I t was presumed that there was slight
"
Institute of Scientific and Industrial Research, Osaka University, Sakai.Vol 11 (No. 29) (1959)
Fig 1. Whole line profiles of legume starches
difference in t h e line profiles for starches from t h e same legume seed according to t h e origin T h e starches from kidney bean. and sword bean belonged to type C very near to type A; it was assumed t h a t these starches might be t h e composites of 85% type A and 15% type
B
T h e starches from hyacinth bean and broad bean a r e similar to sweet-potato starch a s reported by HIZUKURI and NIKUNI"~), i e they might be said t o be t h e composites of 80% type A and 20% type B (Table 1) I tTable 1. The proportion of type A and type B in t h e crystalline parts of various starches
- --
was also noted that the starch from hyacinth bean showed a ring corresponding t o ring 6a of type B As shown in Table 2, there could be found no relations of t h e proportion of type A and type
B
X-ray
patterns Origin of starches(12)
Propor tion of Kinds of legumes type A.
%
type B.%
o
I
Mung 90 85 80 60 45 0 C B 10 15 20 40 55 100 Tapioca Sweet potato Dzoscor~a japonica ' ~ u e r a r z a hirsuta Potato Kidney beanI
$:i.ni:2ean
OLIVE 香川大学学術情報リポジトリ
236 Tech Bull Fac Agr Kaga n a Univ by this X-ray diffractometr ic study with granule size,(') amylose content,c6) or am ylogr am (')
Table 2 Various properties among legume starches
Kinds of legumes Size of ( I ) Amylose (" granules content I I Dolichos lablab
1
26 b 23 B B Canavalia gladiata 38 a1
221
B Pr portion of type A by X-ray diffraction 80 100 (or 85) 85REFERENCES
(1) KAWAMURA, S , TUBOI, Y , HUZII, T : T h i sBulletin, 7 , 87-92(1955).
2
,
FUKUBA, H : This Bulletin, 9 , 38-45(1957)(3)
, TADA,
N
: T h i s Bulletin, 9,
99- 104(1957).
(4)
,
: Nippon Nzgez-kagaku Kaishi, 33, 296- 300(1959).(5) P, -- : Dgmpun Kagy; Gakkazshi
6 , 48-51(1959).
(6)
--,
: Ibid , 51- 7 (1959)(7) - : Ibid , 57- 9 (1959).
(8)
-
: Nippon N$gei-kagaku Kaishi, 33, 300- 4 (1959)(9) FUWA, H : Denpun Kagaku (ed Z Nikuni)
,
175- 238,Tokyo, Asakura Syoten (1951) (10) MURAKAMI, H : Ibzd, revised edition, 593- 8
(1955)
(11) HIZUKURI, S , NIKUNI, Z : Nippon N$gsi-kagaku Kaishi, 31, 371- 4 (1957).
(12) - t
-
: Ibid , 525-711957).(13) )"- : -Ibid ,132, 661- 7 (1958)
r;
1
_
-
-.-=?? (14) NIKUNI, Z , FUWA, H , TAISUMI C : Ibzd, 22,
91- 3 (1948)
