998
Specialia
r e p o r t e d in figure 1. F o r t h i s e x p e r i m e n t , t h e S e p h a d e x was swelled a n d e l u t e d w i t h a s o l u t i o n of 5 m M tris-HC1 b u f f e r (pH 8.0) c o n t a i n i n g 0.2 m M U T P a n d 2 m M 1V[gCl~, b e c a u s e Mg ++ a n d p a r t i c u l a r l y U T P stabilize t h e 0.6
0.4
~0.2
E v--
D8 GMPc Fig. 2. Effects of DBcGMP on the 2 forms of nucleoside phosphotransferase of chick embryo retina. Peak I (tube numbers 11-15)
and peak II (tube numbers 19-23) were collected separately and 200 ill of each peak were utilized for the incubation sample. The activity was measured by using as phosphate donor UMP ( 9169 for peak I and AMP (D--O) for peak II. Data are the means ~ SE of 6 separate experiments.
EXPERIENTIA 33/8
u n s t a b l e f o r m of nucleoside p h o s p h o t r a n s f e r a s e 6. T h e figure shows 2 p e a k s of a c t i v i t y : t h e first corresponds, as p r e v i o u s l y d e m o n s t r a t e d 6, t o t h e u n s t a b l e n u c l e o s i d e p h o s p h o t r a n s f e r a s e a n d i t prefers U M P as p h o s p h a t e d o n o r , while t h e s e c o n d i s r e p r e s e n t e d b y a s t a b l e f o r m w h i c h e m p l o y e s p r e f e r e n t i a l l y A M P as s u b s t r a t e . As s h o w n in figure 2, D B c G M P m a r k e d l y i n h i b i t s t h e n u c l e o s i d e p h o s p h o t r a n s f e r a s e of p e a k I, w h i l e a n y s i g n i f i c a t i v e effect was n o t o b s e r v e d for t h e a c t i v i t y of p e a k I I . P r e v i o u s l y ~ we h a v e h y p o t h e s i z e d t h a t t h e n u c l e o s i d e p h o s p h o t r a n s f e r a s e is p r e s e n t in t h e c h i c k e m b r y o r e t i n a a t l e a s t i n 2 d i f f e r e n t forms, w h i c h could b e a n expression of t h e s a m e e n z y m e a t d i f f e r e n t aggreg a t i o n states. I t is possible t h a t D B c G M P f a c i l i t a t e s t h e c o n v e r s i o n of t h e f o r m w i t h h i g h e r m . w t i n t o a d i s a g g r e g a t e d state. T h i s s t a t e c o u l d b e r e p r e s e n t e d b y t h e s t a b l e nucleoside p h o s p h o t r a n s f e r a s e , a n e n z y m a t i c a c t i v i t y w h i c h is able to utilize as p h o s p h a t e d o n o r s also t h e a d e n i n e nucleotides. T h e s e c o n s i d e r a t i o n s c o u l d e x p l a i n w h y t h e D B c G M P causes a n i n c r e m e n t of t h e t h y m i d i n e p h o s p h o r y l a t i n g r a t e w h e n t h e r e a c t i o n is m e a s u r e d , b y u s i n g A M P as p h o s p h a t e d o n o r , in t h e 105,000 g s u p e r n a t a n t . F u r t h e r m o r e , b e c a u s e i t seems t h a t t h e nucleoside p h o s p h o t r a n s f e r a s e t a k e s p a r t in t h e c o n t r o l of t h e e n d o g e n o u s pools of nucleosides a n d n u c l e o t i d e s , t h e effects of D B c G M P o n t h i s a c t i v i t y could i n d i c a t e t h e p a r t i c i p a t i o n of t h i s c o m p o u n d i n t h e r e g u l a t i o n of nucleotide metabolism.
Absorption andlbiotransformation of L( + ) vtt _ a r t a r i c , ~ a c i d in rats L. F. C h a s s e a u d , W . H. D o w n a n d D. K i r k p a t r i c k
Huntingdon Research Centre, Department o/ Metabolism and Pharmacokinetics, Huntingdon PE18 6ES (England), 18 January 1977 Summary. Oral or p a r e n t e r a l doses of m o n o s o d i u m l * C - L ( + ) - t a r t r a t e (400 mg/kg) are r a p i d l y e x c r e t e d b y r a t s a n d a p r o p o r t i o n c o m p l e t e l y m e t a b o l i z e d t o CO v T h e oral dose was w e l l - a b s o r b e d . T a r t a r i c acid a n d its s a l t s are used in m e d i c i n e a n d in t h e food i n d u s t r y . I n h u m a n s , t h e acid is t h o u g h t t o b e p o o r l y a b s o r b e d 1 a n d w h e n g i v e n orally, t o b e m e t a b o lized b y t h e g u t flora 2, 3, since i t is r e a d i l y m e t a b o l i z e d b y m i c r o o r g a n i s m s s u c h as P s e u d o m o n a s p u t i d a ~ a n d P e n i 90 J
o 70
.~ 5o
g o
o :
E
r
24 Time
48h
Cumulative excretion of radioactivity in the urine ( I , 0) and expired air (D, C) of rats dosed orally or i.v. respectively with monosodium 14C-L(+)-tartrate (400 mg/kg).
cillium charlesii 5, w h i c h c o n v e r t i t t o g l y c e r a t e a n d CO v S t u d i e s in dogs a n d r a b b i t s h a v e s h o w n t h a t oral doses of t a r t a r i c acid were e x c r e t e d in t h e u r i n e as u n c h a n g e d c o m p o u n d , t h e p r o p o r t i o n of w h i c h d e c r e a s e d w i t h i n c r e a s i n g doses 6. M u c h of t h e t a r t a r i c acid used is o b t a i n e d as a b y p r o d u c t of w i n e m a n u f a c t u r e a n d is therefore the naturally-occurring L(+) formL Thus the a b s o r p t i o n a n d b i o t r a n s f o r m a t i o n of t a r t a r i c acid h a s b e e n e v a l u a t e d u s i n g t h e 14C-L(+) form. Materials. (1,4-1*C)-DL-Tartaric acid c~f specific a c t i v i t y 2 - 1 0 m C i / m m o l e s was o b t a i n e d f r o m T h e R a d i o c h e m i c a l Centre, A m e r s h a m , E n g l a n d , a n d w a s resolved i n t o t h e L( + ) - i s o m e r s. T h e r e s u l t i n g m o n o s o d i u m 14C-L(+)1 L. S. Goodman and A. Gilman, The Pharmacological Basis of Therapeutics, 4th ed. Macmillan, London 1970. 2 F.P. Underhill, F. I. Peterman, T. C. Jaleski and C. S. Leonard, J. Pharmac. exp. Ther. 43, 381 (1931). 3 P. Finkle, J. biol. Chem. 700, 349 (1933). 4 L.D. Kohn and W. B. Jakoby, J. biol. Chem. 243, 2465 (1968). 5 K.P. Klatt, P. D. Rick and J. E. Gander, Archs Biochem. Biophys. 134, 335 (1969). 6 F.P. Underhill, C. S. Leonard, E. G. Gross and T. C. Jaleski, J, Pharmae. exp. Ther. 43, 359 (1931). 7 M. H, M. Arnold, Acidulants for Food and Beverages. Food Trade Press Ltd., London 1975. 8 J. Read and W. G. Reid, J. Soc. chem. Ind. 47, 8 (1928).
15.8. 1977
Specialia
t a r t r a t e was s h o w n b y p a p e r c h r o m a t o g r a p h y in a s o l v e n t s y s t e m of b u t a n - l - o l : acetic acid : w a t e r (12 : 3 : 5, v/v) t o b e a t l e a s t 9 9 % r a d i o c h e m i c a l l y pure. N o n - r a d i o a c t i v e m o n o s o d i u m L( + ) - t a r t r a t e was p r o v i d e d b y Fides, U n i o n Fiduciaire, Switzerland. Methods. A d u l t C F Y r a t s (b.wt 200-250 g), a s t r a i n of S p r a g u e - D a w l e y origin were o b t a i n e d f r o m A n g l i a L a b o r a t o r y A n i m a l s , H u n t i n g d o n , E n g l a n d , a n d were Mlowed a p e l l e t d i e t a n d w a t e r a d l i b i t u m . T h e r a t s were dosed b y oral i n t u b a t i o n or b y i n j e c t i o n i n t o a tail v e i n w i t h m o n o s o d i u m 1 4 C - L ( + ) - t a r t r a t e a t a dose level of 400 m g / k g in a q u e o u s solution. T h e r a t s were k e p t singly in glass m e t a b o l i s m cages, w h i c h e n a b l e d nrit~e, faeces a n d e x p i r e d air t o be s e p a r a t e l y c o l l e c t e d , t h e u r i n e i n t o r e c e i v e r s cooled in solid CO v a n d t h e e x p i r e d air (14CO2) into traps containing ethanolamine: 2-ethoxyethanol (1:4, v / v ) . T h e r a t s were sacrificed a f t e r 2 days. R a d i o a c t i v i t y was m e a s u r e d u s i n g p r o c e d u r e s p r e v i o u s l y des c r i b e d 9. Results. A n oral dose of m o n o s o d i u m l * C - L ( + ) - t a r t r a t e was r a p i d l y a b s o r b e d a n d e x c r e t e d b y rats. E x c r e t i o n of r a d i o a c t i v i t y in t h e u r i n e was a l m o s t c o m p l e t e d w i t h i n 12 h a n d in t h e e x p i r e d air w i t h i n 24 h (figure). A t 48 h a f t e r t h e oral dose t o r a t s (33 + 39), 70.1 • 4 . 1 % ,
O n a r e l a t i o n of l o w p h o s p h o g l u c o m u t a s e
999
13.6 • 7.3% a n d 15.6 ~: 2.7% h a d b e e n e x c r e t e d in t h e urine, faeces a n d e x p i r e d air r e s p e c t i v e l y ( i SD). A f t e r t h e i.v. dose, 81.8 :~ 4 . 9 % , 0.9 :L 1.1% a n d 7.5 -t- 0.5% h a d b e e n e x c r e t e d b y t h e s e r o u t e s r e s p e c t i v e l y ( • SD). R a t e s of e x c r e t i o n of r a d i o a c t i v i t y b y m a l e a n d f e m a l e a n i m a l s were similar. Discussion. T h e u r i n a r y e x c r e t i o n d a t a o b t a i n e d in t h e s e s t u d i e s are i n a g r e e m e n t w i t h a n earlier i n v e s t i g a t i o n w h i c h r e p o r t e d t h a t r a t s e x c r e t e d in t h e u r i n e a m e a n of 6 8 % of a n oral dose of 400 m g / k g of t a r t r a t e g i v e n as R o c h e l l e s a l t 6. H o w e v e r , t h e earlier w o r k ~ s u g g e s t e d t h a t t a r t a r i c acid was o n l y m e t a b o l i z e d b y t h e g u t flora a n d n o t b y t h e tissues. T h e r e s u l t s o b t a i n e d in t h e s e s t u d i e s c o n t r a d i c t t h i s view since s i g n i f i c a n t a m o u n t s of 14CO~ were e x c r e t e d a f t e r p a r e n t e r a l a d m i n i s t r a t i o n of 14C-L ( + ) t a r t r a t e s h o w i n g t h a t s y s t e m i c m e t a b o l i s m of t a r t a r i c acid occurred. C o m p a r i s o n of r e s u l t s o b t a i n e d a f t e r oral or i.v. doses i n d i c a t e s t h a t a n oral dose of L( + ) - t a r t r a t e was e x t e n s i v e l y a b s o r b e d a n d t h a t a p a r t was c o m p l e t e l y m e t a b o l i z e d t o 14CO2 a f t e r oral or p a r e n t e r a l a d m i n i s t r a tion. 9
R.R. Brodie, L. F. Chasseaud, L. F. Elsom, E. R. Franklin arid T. Taylor, Arzneimittel-Forsch. 26, 896 (1976).
activity to s t a r c h a c c u m u l a t i o n in s p i k e d s a n d a l
K. P a r t h a s a r a t h i , C. R. R a n g a s w a m y a n d D. R. C. B a b u
Forest Research Laboratory, Bangalore-560003 (India), 2 November 1976 Summary. A c o n s i d e r a b l e decline in t h e a c t i v i t y of p h o s p h o g l u c o m u t a s e a p p e a r e d to be a cause for t h e s t a r c h a c c u m u l a t i o n in t h e leaves of s a n d a l a f f e c t e d b y spike disease. I n t h e s a n d a l ( S a n t a l u m a l b u m L.) affected b y spike disease, m y c o p l a s m a l in n a t u r e , t h e leaves show s t u n t e d g r o w t h , chlorosis a n d a c c u m u l a t i o n 1 of large a m o u n t s of s t a r c h a n d sugars, a n d t h e r e is necrosis of p h l o e m elem e n t s in t h e diseased s t a t e . T h e s u g a r a c c u m u l a t i o n in t h e c h l o r o t i c s p i k e d leaves, p r e s u m a b l y o c c u r r i n g as a r e s u l t of i m p a i r e d t r a n s l o c a t i o n due to t h e necrosis of p h l o e m elements, n a t u r a l l y leads to i n c r e a s e d s t a r c h f o r m a t i o n t o p r e v e n t a b n o r m a l rise in t h e o s m o t i c pressure of t h e tissue. H o w e v e r , t h e e n z y m e s r e l a t e d t o s t a r c h b r e a k d o w n also d e t e r m i n e s t a r c h - b a l a n c e in t h e tissue. E x a m i n a t i o n of t h e d i a s t a t i c a c t i v i t y of t h e diseased s a n d a l leaves, s h o w e d it, c o n t r a r y to e x p e c t a t i o n , to be
Phosphorylase and phosphoglucolnutase activities and starch content in healthy and spiked sandal leaves
Phosphorylase activity* ([xg Pi liberated]100 mg tissue/30 min) Phosphoglncomutase activity* (~tg Pi converted/150 mg tissue/30 min) Starch content* (rag/100 g dry leaf)
Healthy Leaves Young Mature
Spiked Leaves Young Mature
4.15
5.20
18.30
(0.36) 51.7
(0.49) 78.0
( 0 . 5 6 ) (0.61) 45.4 10.3
(2.7) 105.7 (11.8)
(4.4) 73.3 (12.1)
(3.5) (1.7) 179.2 461.0 ( 1 6 . 5 ) (48.5)
18.70
a t a h i g h level ~, t h u s a p p a r e n t l y s h o w i n g n o c o r r e l a t i o n to t h e h i g h s t a r c h c o n t e n t t h e r e i n . I t is n o w k n o w n t h a t in t h e p l a n t t h e b r e a k d o w n of s t a r c h in tissues o t h e r t h a n s t o r a g e tissues a n d g e r m i n a t i n g seeds 3-5 is l a r g e l y b r o u g h t a b o u t b y p h o s p h o r y l a s e 6-s. G l u c o s e - l - p h o s p h a t e (G-l-P) f o r m e d d u r i n g t h e p h o s p h o r o l y s i s , is c o n v e r t e d t o G - 6 - P b y p h o s p h o g l u c o m u t a s e for e n t r y i n t o glycolysis. T h e r e fore, t h e s e 2 e n z y m e s , of r e l e v a n c e to s t a r c h b a l a n c e in t h e tissue, w e r e s t u d i e d in t h e h e a l t h y a n d s p i k e d s a n d M leaves to e x a m i n e t h e i r r e l a t i o n to t h e s t a r c h a c c u m u l a t i o n in t h e diseased s t a t e . Material and methods. S a m p l e s of y o u n g a n d m a t u r e leaves f r o m h e a l t h y a n d s p i k e d s a n d a l t r e e s were t a k e n d u r i n g J u l y a n d S e p t e m b e r r e s p e c t i v e l y , selecting 6 t r e e s in e a c h case. As t h e s p i k e d t r e e s r e m a i n v e g e t a t i v e t h r o u g h o u t , t h e h e a l t h y leaf s a m p l e s also were t a k e n f r o m t r e e s in v e g e t a t i v e s t a g e for p r o p e r c o m p a r i s o n . 1 2 3 4 5 6 7 8
*Average of 6 replications. Figures in parenthesis represent SD.
A.V. Varadaraja Iyengar, J. Indian Inst. Sci. 71A, 97 (1928). M. Sreenivasaya and B. N. Sastri, J. Indian Inst. Sei. 11A, 23 (1928). T. Akazawa, in: Plant Biochemistry. Ed. J. Bonner and J. E. Varner, Academic Press, New York 1965. T. Murata, T. Akazawa and S. Fukuchi, P1. Physiol. d3, 1899 (1968). R.R. Swain and E. E. Dekker, Biochim. biophys. Aeta 722, 87 (1966). M.H. Ewart, D. Siminovitch and D. R. Brigs, P1. Physiol. 29, 407 (1954). T . W . Goodwin and E. I. Mercer, Introduction to Plant Biochemistry. Pergamon Press, New York 1972. D.J. Manners, in: Plant Carbohydrate Biochemistry. Ed. J. 13. Pridham, Academic Press, London 1974.
Specialia
r e p o r t e d in figure 1. F o r t h i s e x p e r i m e n t , t h e S e p h a d e x was swelled a n d e l u t e d w i t h a s o l u t i o n of 5 m M tris-HC1 b u f f e r (pH 8.0) c o n t a i n i n g 0.2 m M U T P a n d 2 m M 1V[gCl~, b e c a u s e Mg ++ a n d p a r t i c u l a r l y U T P stabilize t h e 0.6
0.4
~0.2
E v--
D8 GMPc Fig. 2. Effects of DBcGMP on the 2 forms of nucleoside phosphotransferase of chick embryo retina. Peak I (tube numbers 11-15)
and peak II (tube numbers 19-23) were collected separately and 200 ill of each peak were utilized for the incubation sample. The activity was measured by using as phosphate donor UMP ( 9169 for peak I and AMP (D--O) for peak II. Data are the means ~ SE of 6 separate experiments.
EXPERIENTIA 33/8
u n s t a b l e f o r m of nucleoside p h o s p h o t r a n s f e r a s e 6. T h e figure shows 2 p e a k s of a c t i v i t y : t h e first corresponds, as p r e v i o u s l y d e m o n s t r a t e d 6, t o t h e u n s t a b l e n u c l e o s i d e p h o s p h o t r a n s f e r a s e a n d i t prefers U M P as p h o s p h a t e d o n o r , while t h e s e c o n d i s r e p r e s e n t e d b y a s t a b l e f o r m w h i c h e m p l o y e s p r e f e r e n t i a l l y A M P as s u b s t r a t e . As s h o w n in figure 2, D B c G M P m a r k e d l y i n h i b i t s t h e n u c l e o s i d e p h o s p h o t r a n s f e r a s e of p e a k I, w h i l e a n y s i g n i f i c a t i v e effect was n o t o b s e r v e d for t h e a c t i v i t y of p e a k I I . P r e v i o u s l y ~ we h a v e h y p o t h e s i z e d t h a t t h e n u c l e o s i d e p h o s p h o t r a n s f e r a s e is p r e s e n t in t h e c h i c k e m b r y o r e t i n a a t l e a s t i n 2 d i f f e r e n t forms, w h i c h could b e a n expression of t h e s a m e e n z y m e a t d i f f e r e n t aggreg a t i o n states. I t is possible t h a t D B c G M P f a c i l i t a t e s t h e c o n v e r s i o n of t h e f o r m w i t h h i g h e r m . w t i n t o a d i s a g g r e g a t e d state. T h i s s t a t e c o u l d b e r e p r e s e n t e d b y t h e s t a b l e nucleoside p h o s p h o t r a n s f e r a s e , a n e n z y m a t i c a c t i v i t y w h i c h is able to utilize as p h o s p h a t e d o n o r s also t h e a d e n i n e nucleotides. T h e s e c o n s i d e r a t i o n s c o u l d e x p l a i n w h y t h e D B c G M P causes a n i n c r e m e n t of t h e t h y m i d i n e p h o s p h o r y l a t i n g r a t e w h e n t h e r e a c t i o n is m e a s u r e d , b y u s i n g A M P as p h o s p h a t e d o n o r , in t h e 105,000 g s u p e r n a t a n t . F u r t h e r m o r e , b e c a u s e i t seems t h a t t h e nucleoside p h o s p h o t r a n s f e r a s e t a k e s p a r t in t h e c o n t r o l of t h e e n d o g e n o u s pools of nucleosides a n d n u c l e o t i d e s , t h e effects of D B c G M P o n t h i s a c t i v i t y could i n d i c a t e t h e p a r t i c i p a t i o n of t h i s c o m p o u n d i n t h e r e g u l a t i o n of nucleotide metabolism.
Absorption andlbiotransformation of L( + ) vtt _ a r t a r i c , ~ a c i d in rats L. F. C h a s s e a u d , W . H. D o w n a n d D. K i r k p a t r i c k
Huntingdon Research Centre, Department o/ Metabolism and Pharmacokinetics, Huntingdon PE18 6ES (England), 18 January 1977 Summary. Oral or p a r e n t e r a l doses of m o n o s o d i u m l * C - L ( + ) - t a r t r a t e (400 mg/kg) are r a p i d l y e x c r e t e d b y r a t s a n d a p r o p o r t i o n c o m p l e t e l y m e t a b o l i z e d t o CO v T h e oral dose was w e l l - a b s o r b e d . T a r t a r i c acid a n d its s a l t s are used in m e d i c i n e a n d in t h e food i n d u s t r y . I n h u m a n s , t h e acid is t h o u g h t t o b e p o o r l y a b s o r b e d 1 a n d w h e n g i v e n orally, t o b e m e t a b o lized b y t h e g u t flora 2, 3, since i t is r e a d i l y m e t a b o l i z e d b y m i c r o o r g a n i s m s s u c h as P s e u d o m o n a s p u t i d a ~ a n d P e n i 90 J
o 70
.~ 5o
g o
o :
E
r
24 Time
48h
Cumulative excretion of radioactivity in the urine ( I , 0) and expired air (D, C) of rats dosed orally or i.v. respectively with monosodium 14C-L(+)-tartrate (400 mg/kg).
cillium charlesii 5, w h i c h c o n v e r t i t t o g l y c e r a t e a n d CO v S t u d i e s in dogs a n d r a b b i t s h a v e s h o w n t h a t oral doses of t a r t a r i c acid were e x c r e t e d in t h e u r i n e as u n c h a n g e d c o m p o u n d , t h e p r o p o r t i o n of w h i c h d e c r e a s e d w i t h i n c r e a s i n g doses 6. M u c h of t h e t a r t a r i c acid used is o b t a i n e d as a b y p r o d u c t of w i n e m a n u f a c t u r e a n d is therefore the naturally-occurring L(+) formL Thus the a b s o r p t i o n a n d b i o t r a n s f o r m a t i o n of t a r t a r i c acid h a s b e e n e v a l u a t e d u s i n g t h e 14C-L(+) form. Materials. (1,4-1*C)-DL-Tartaric acid c~f specific a c t i v i t y 2 - 1 0 m C i / m m o l e s was o b t a i n e d f r o m T h e R a d i o c h e m i c a l Centre, A m e r s h a m , E n g l a n d , a n d w a s resolved i n t o t h e L( + ) - i s o m e r s. T h e r e s u l t i n g m o n o s o d i u m 14C-L(+)1 L. S. Goodman and A. Gilman, The Pharmacological Basis of Therapeutics, 4th ed. Macmillan, London 1970. 2 F.P. Underhill, F. I. Peterman, T. C. Jaleski and C. S. Leonard, J. Pharmac. exp. Ther. 43, 381 (1931). 3 P. Finkle, J. biol. Chem. 700, 349 (1933). 4 L.D. Kohn and W. B. Jakoby, J. biol. Chem. 243, 2465 (1968). 5 K.P. Klatt, P. D. Rick and J. E. Gander, Archs Biochem. Biophys. 134, 335 (1969). 6 F.P. Underhill, C. S. Leonard, E. G. Gross and T. C. Jaleski, J, Pharmae. exp. Ther. 43, 359 (1931). 7 M. H, M. Arnold, Acidulants for Food and Beverages. Food Trade Press Ltd., London 1975. 8 J. Read and W. G. Reid, J. Soc. chem. Ind. 47, 8 (1928).
15.8. 1977
Specialia
t a r t r a t e was s h o w n b y p a p e r c h r o m a t o g r a p h y in a s o l v e n t s y s t e m of b u t a n - l - o l : acetic acid : w a t e r (12 : 3 : 5, v/v) t o b e a t l e a s t 9 9 % r a d i o c h e m i c a l l y pure. N o n - r a d i o a c t i v e m o n o s o d i u m L( + ) - t a r t r a t e was p r o v i d e d b y Fides, U n i o n Fiduciaire, Switzerland. Methods. A d u l t C F Y r a t s (b.wt 200-250 g), a s t r a i n of S p r a g u e - D a w l e y origin were o b t a i n e d f r o m A n g l i a L a b o r a t o r y A n i m a l s , H u n t i n g d o n , E n g l a n d , a n d were Mlowed a p e l l e t d i e t a n d w a t e r a d l i b i t u m . T h e r a t s were dosed b y oral i n t u b a t i o n or b y i n j e c t i o n i n t o a tail v e i n w i t h m o n o s o d i u m 1 4 C - L ( + ) - t a r t r a t e a t a dose level of 400 m g / k g in a q u e o u s solution. T h e r a t s were k e p t singly in glass m e t a b o l i s m cages, w h i c h e n a b l e d nrit~e, faeces a n d e x p i r e d air t o be s e p a r a t e l y c o l l e c t e d , t h e u r i n e i n t o r e c e i v e r s cooled in solid CO v a n d t h e e x p i r e d air (14CO2) into traps containing ethanolamine: 2-ethoxyethanol (1:4, v / v ) . T h e r a t s were sacrificed a f t e r 2 days. R a d i o a c t i v i t y was m e a s u r e d u s i n g p r o c e d u r e s p r e v i o u s l y des c r i b e d 9. Results. A n oral dose of m o n o s o d i u m l * C - L ( + ) - t a r t r a t e was r a p i d l y a b s o r b e d a n d e x c r e t e d b y rats. E x c r e t i o n of r a d i o a c t i v i t y in t h e u r i n e was a l m o s t c o m p l e t e d w i t h i n 12 h a n d in t h e e x p i r e d air w i t h i n 24 h (figure). A t 48 h a f t e r t h e oral dose t o r a t s (33 + 39), 70.1 • 4 . 1 % ,
O n a r e l a t i o n of l o w p h o s p h o g l u c o m u t a s e
999
13.6 • 7.3% a n d 15.6 ~: 2.7% h a d b e e n e x c r e t e d in t h e urine, faeces a n d e x p i r e d air r e s p e c t i v e l y ( i SD). A f t e r t h e i.v. dose, 81.8 :~ 4 . 9 % , 0.9 :L 1.1% a n d 7.5 -t- 0.5% h a d b e e n e x c r e t e d b y t h e s e r o u t e s r e s p e c t i v e l y ( • SD). R a t e s of e x c r e t i o n of r a d i o a c t i v i t y b y m a l e a n d f e m a l e a n i m a l s were similar. Discussion. T h e u r i n a r y e x c r e t i o n d a t a o b t a i n e d in t h e s e s t u d i e s are i n a g r e e m e n t w i t h a n earlier i n v e s t i g a t i o n w h i c h r e p o r t e d t h a t r a t s e x c r e t e d in t h e u r i n e a m e a n of 6 8 % of a n oral dose of 400 m g / k g of t a r t r a t e g i v e n as R o c h e l l e s a l t 6. H o w e v e r , t h e earlier w o r k ~ s u g g e s t e d t h a t t a r t a r i c acid was o n l y m e t a b o l i z e d b y t h e g u t flora a n d n o t b y t h e tissues. T h e r e s u l t s o b t a i n e d in t h e s e s t u d i e s c o n t r a d i c t t h i s view since s i g n i f i c a n t a m o u n t s of 14CO~ were e x c r e t e d a f t e r p a r e n t e r a l a d m i n i s t r a t i o n of 14C-L ( + ) t a r t r a t e s h o w i n g t h a t s y s t e m i c m e t a b o l i s m of t a r t a r i c acid occurred. C o m p a r i s o n of r e s u l t s o b t a i n e d a f t e r oral or i.v. doses i n d i c a t e s t h a t a n oral dose of L( + ) - t a r t r a t e was e x t e n s i v e l y a b s o r b e d a n d t h a t a p a r t was c o m p l e t e l y m e t a b o l i z e d t o 14CO2 a f t e r oral or p a r e n t e r a l a d m i n i s t r a tion. 9
R.R. Brodie, L. F. Chasseaud, L. F. Elsom, E. R. Franklin arid T. Taylor, Arzneimittel-Forsch. 26, 896 (1976).
activity to s t a r c h a c c u m u l a t i o n in s p i k e d s a n d a l
K. P a r t h a s a r a t h i , C. R. R a n g a s w a m y a n d D. R. C. B a b u
Forest Research Laboratory, Bangalore-560003 (India), 2 November 1976 Summary. A c o n s i d e r a b l e decline in t h e a c t i v i t y of p h o s p h o g l u c o m u t a s e a p p e a r e d to be a cause for t h e s t a r c h a c c u m u l a t i o n in t h e leaves of s a n d a l a f f e c t e d b y spike disease. I n t h e s a n d a l ( S a n t a l u m a l b u m L.) affected b y spike disease, m y c o p l a s m a l in n a t u r e , t h e leaves show s t u n t e d g r o w t h , chlorosis a n d a c c u m u l a t i o n 1 of large a m o u n t s of s t a r c h a n d sugars, a n d t h e r e is necrosis of p h l o e m elem e n t s in t h e diseased s t a t e . T h e s u g a r a c c u m u l a t i o n in t h e c h l o r o t i c s p i k e d leaves, p r e s u m a b l y o c c u r r i n g as a r e s u l t of i m p a i r e d t r a n s l o c a t i o n due to t h e necrosis of p h l o e m elements, n a t u r a l l y leads to i n c r e a s e d s t a r c h f o r m a t i o n t o p r e v e n t a b n o r m a l rise in t h e o s m o t i c pressure of t h e tissue. H o w e v e r , t h e e n z y m e s r e l a t e d t o s t a r c h b r e a k d o w n also d e t e r m i n e s t a r c h - b a l a n c e in t h e tissue. E x a m i n a t i o n of t h e d i a s t a t i c a c t i v i t y of t h e diseased s a n d a l leaves, s h o w e d it, c o n t r a r y to e x p e c t a t i o n , to be
Phosphorylase and phosphoglucolnutase activities and starch content in healthy and spiked sandal leaves
Phosphorylase activity* ([xg Pi liberated]100 mg tissue/30 min) Phosphoglncomutase activity* (~tg Pi converted/150 mg tissue/30 min) Starch content* (rag/100 g dry leaf)
Healthy Leaves Young Mature
Spiked Leaves Young Mature
4.15
5.20
18.30
(0.36) 51.7
(0.49) 78.0
( 0 . 5 6 ) (0.61) 45.4 10.3
(2.7) 105.7 (11.8)
(4.4) 73.3 (12.1)
(3.5) (1.7) 179.2 461.0 ( 1 6 . 5 ) (48.5)
18.70
a t a h i g h level ~, t h u s a p p a r e n t l y s h o w i n g n o c o r r e l a t i o n to t h e h i g h s t a r c h c o n t e n t t h e r e i n . I t is n o w k n o w n t h a t in t h e p l a n t t h e b r e a k d o w n of s t a r c h in tissues o t h e r t h a n s t o r a g e tissues a n d g e r m i n a t i n g seeds 3-5 is l a r g e l y b r o u g h t a b o u t b y p h o s p h o r y l a s e 6-s. G l u c o s e - l - p h o s p h a t e (G-l-P) f o r m e d d u r i n g t h e p h o s p h o r o l y s i s , is c o n v e r t e d t o G - 6 - P b y p h o s p h o g l u c o m u t a s e for e n t r y i n t o glycolysis. T h e r e fore, t h e s e 2 e n z y m e s , of r e l e v a n c e to s t a r c h b a l a n c e in t h e tissue, w e r e s t u d i e d in t h e h e a l t h y a n d s p i k e d s a n d M leaves to e x a m i n e t h e i r r e l a t i o n to t h e s t a r c h a c c u m u l a t i o n in t h e diseased s t a t e . Material and methods. S a m p l e s of y o u n g a n d m a t u r e leaves f r o m h e a l t h y a n d s p i k e d s a n d a l t r e e s were t a k e n d u r i n g J u l y a n d S e p t e m b e r r e s p e c t i v e l y , selecting 6 t r e e s in e a c h case. As t h e s p i k e d t r e e s r e m a i n v e g e t a t i v e t h r o u g h o u t , t h e h e a l t h y leaf s a m p l e s also were t a k e n f r o m t r e e s in v e g e t a t i v e s t a g e for p r o p e r c o m p a r i s o n . 1 2 3 4 5 6 7 8
*Average of 6 replications. Figures in parenthesis represent SD.
A.V. Varadaraja Iyengar, J. Indian Inst. Sci. 71A, 97 (1928). M. Sreenivasaya and B. N. Sastri, J. Indian Inst. Sei. 11A, 23 (1928). T. Akazawa, in: Plant Biochemistry. Ed. J. Bonner and J. E. Varner, Academic Press, New York 1965. T. Murata, T. Akazawa and S. Fukuchi, P1. Physiol. d3, 1899 (1968). R.R. Swain and E. E. Dekker, Biochim. biophys. Aeta 722, 87 (1966). M.H. Ewart, D. Siminovitch and D. R. Brigs, P1. Physiol. 29, 407 (1954). T . W . Goodwin and E. I. Mercer, Introduction to Plant Biochemistry. Pergamon Press, New York 1972. D.J. Manners, in: Plant Carbohydrate Biochemistry. Ed. J. 13. Pridham, Academic Press, London 1974.
