BIOCHEMICAL

Vol. 76, No. 2, 1977

AND BIOPHYSICAL

RESEARCH COMMUNICATIONS

PROTECTION OF CHLOROPHYLL BY PHOSPHOLIPIDS William Department

Received

March

Stillwell

FROM PHOTOOXIDATION

and H. Ti Tien

of Biophysics, East Lansing,

Michigan Michigan

State 48824

University

21,1977

SUMMARY: Rapid photooxidation of chlorophyll in chloroform was shown to be partly inhibited by various biologically significant compounds including Scarotene, xanthophyll and several synthetic and natural phospholipids. Protection from bleaching by phospholipids was most evident for the phosphatidyl cholines and was less for the phosphatidyl ethanolamines. Protection was independent of the chain length and unsaturation of the esterified fatty acids and depended primarily on the nature of the polar head group of the phospholipids. The irreversible for

many years.

quantasomes

Bleaching

(4),

of chlorophyll the

could

the

(10)

have

be slowed

has been

proposed

to higher

membrane. also It

However,

be playing

in;

the

in liposomes

D,L-a-cephalin

and phosphatidyl

monooleate,

(E)

ethanolamine,

brain

(B),

(E),

L-a-phosphatidyl

(F) > asolectin

best

(A),

(D),

monostearate

in preventing

the polar

more

glyceryl

were

following

was obtained egg>

lecithin

from bovine

choline

glyceryl

the

> L-a-phosphatidyl

extract,

extracts,

Since

monoricinoleate,

II-s

from

and

some protection.

materials III-E

ethanolamine,

lecithin

intermediate.

type

with

of light

photooxidation,

biological

(G) and (H),

in phosphatidyl

amounts

from

(vegetable)

type

cholines,

from

chlorophyll

(H),

eggs >

(C) > brain

The phosphatidyl

the ravages

from

choline

IX-E

brain

chlorophyll provided

extracted

type

bovine

RESEARCH COMMUNICATIONS

of chlorophyll

L-a-phosphatidyl

L-a-lecithin

(A).

tested

of phospholipids

(Figure

II

in protecting

AND BIOPHYSICAL

for

(adjacent

maximum protection ring

of chlorophyll

BIOCHEMICAL

Vol. 76, No. 2, 1977

The aerobic choline,

Figure 4. L-a-phosphatidyl

in

the lipid

of chlorophyll to in free

photodegradation type III-E/chlorophyll

is partly

bilayer toward

responsible

photooxidation

compounds

were

also

chlorophyll

from

Figure

Chlorophyll

was very

3.

photooxidized

in the

pheophytins)

to prevent shown

about

(Figure

the marked

to the

increase

of the

in stability

and quantasomes

solutions

unstable of acetic

for

a long

These

the photooxidation to signiciantly

results

as opposed

acid.

Acid

time.

the as the

for

their

was rapid

lability

Some protection

protecting

in

was afforded

by

(a compound

(2,6)).

of photobleaching,

classic

in

when

(resulting

and benzoquinone

rate

ability

are presented

of bacteriochlorophyll slow

as effective

to test

and degradation

the antioxidant-a-tocopherol

one fifth

Xanthophyll however,

agent,

it

was

B-carotene

3).

Recently liposomes

for

photooxidation.

presence

has been known

the base-pyridine,

only

of chlorophyll as a function mole ratio.

in chloroplasts

added

to protect

was also

RESEARCH COMMUNICATIONS

solution.

Other

known

AND BIOPHYSICAL

several

papers

in an attempt

was demonstrated

have appeared

to model

on incorporation

the thylakoid

to be much more resistant

membrane to photooxidation

237

of chlorophyll (15-18).

into

Chlorophyll

in liposomes

than

Vol. 76, No. 2, 1977

in free

solution

(6).

the protection outlined is

In free by the

solution time

increase than

Therefore,

of phospholipids 4 the

phosphatidyl

the

in liposomes, range

increase

in

of chlorophyll

presence

of such hyrophobic

well

as water

of degrdation

does not

its

stability free

efficiency

ACKNOWLEDGEMENTS: This Service Grant, GM-14971.

30 molecules ratio

about

1.

further

can not

solution

photooxidation appears

accommodate

of phospholipid. is well

into

of chlorophyll

to be the result bilayer

as e-carotene

be incorporation

as well

the

was supported

are

currently

by a United

-in

of proper as the immediate

and xanthophyll.

of appropriate

Such studies work

reaches

photooxidation.

in the phospholipid

proteins.

in chloroform

maximum protecting ratio

of

as

ratio.

liposomes

toward

molecules

of chlorophyll

in a substantial

per

terms

III-E/chlorophyll

mole

result

chlorophyll

be provided soluble

type

reaches

in

of chlorophyll

choline,

of chlorophyll

for in

to that

might

rate

the phospholipidJchlorophyl1

orientation

stability

be understood

to the photooxidation

Chlorophyll-containing

one molecule

as opposed

could

choline/chlorophyll

choline

in protection. about

stability

choline

phosphatidyl

phosphatidyl

The great

increased

AND BIOPHYSICAL RESEARCH COMMUNICATIONS

the L-a-phosphatidyl

maximum protection

vivo

This

In Figure

against

Additional

more

role

here.

plotted

BIOCHEMICAL

Additional

lipoproteins

as

in progress. States

Public

Health

REFERENCES: 1. 2. 3. 4. 5. 6. 7. a. 9. 10. 11. 12. 13. 14. 15. 16. 17. 18.

11, 363-410. Krasnovsky, A. A. (1960) Ann. Rev. Plant Physiol. Goedheer, J. C. (1958) Biochim. Biophys. Acta 27, 478-490. Dilung, I. I. (1958) Ukrain. Khim. Zhur. 24, 202-207. Saer,K. and Calvin, M. (1962) Biochim. Biophys. Acta 64, 324-339. Thomas, J. B. and Nijhuis, H. H. (1968) 153, 868-877. Stillwell, W. and Tien, H. Ti, submitted for publication. Stanier, R. Y. (1959) Brookhaven Symp. Biol. no. 11, 47-53. Cohen-Bazire, G. and Stanier, R. Y. (1958) Nature 181, 250-252. Griffiths, M., Sistrom, W. R., Cohen-Bazire, G. and Stanier, R. Y. (1955) Nature 176, 1211-1214. Gregory, R. P. F. (1977) Biochemistry of Photosynthesis, Wiley and Sons, Inc., New York. Tien, H. Ti (1974) Bilayer Lipid Membranes (BLM) p. 546, Marcel Dekker, Inc., New York. Mackinney, G. (1941) J. Biol. Chem. 140, 315-322. E. (1971) J. Biol. Chem. 246, 5477-5487. Kagawa, Y. and Racker, Miller, C. and Racker, E. (1976) J. Memb. Biol. 26, 319-333. Weller, H. and Tien, H. Ti (1973) Biochem. Biophys. Acta, 325, 433-440. Oettmeier, W., Norris, .I. R. and Katz, J. J. (1976) Biochem. Biophys. Res. comm. 71, 445-451. Ritt, E. and Walz, D. (1976) J. Memb. Biol. 27, 41-54. Mangel, M. (1976) Biochim. Biophys. Acta 430, 459-466. 238

Protection of chlorophyll by phospholipids from photooxidation.

BIOCHEMICAL Vol. 76, No. 2, 1977 AND BIOPHYSICAL RESEARCH COMMUNICATIONS PROTECTION OF CHLOROPHYLL BY PHOSPHOLIPIDS William Department Received...
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