Some Aspects of the Biochemistry of Apple and Pear Fruits

Hulme, A. C.

doi:10.1016/s0065-2628(08)60022-1

Cited by 121 publications

(39 citation statements)

References 171 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The particles obtained from the high speed centrifugation were washed in 0.25 M sucrose and resedimented at 17,000 X G. The particles were finally suspended in 6 ml of 0.25 M sucrose and 0.001 M adenosine triphosphate (ATP) adjusted to pH 7.0. These suspensions generally had a nitrogen (N) (10,15), and to the acidity of the cell sap (17). The effects of polyphenols were considerably reduced by eliminating the peel, which contains the bulk of these substances, and by introducing 0.01 M ascorbic acid into the homogenizing medium, thus maintaining the polyphenols in the reduced (non-inhibitory) state (12).…”

Section: Methodsmentioning

confidence: 99%

Oxidative Activity of Cytoplasmic Particles of Apples: Electron Transfer Chain

Lieberman

1960

Plant Physiol.

View full text Add to dashboard Cite

PLANT INDUSTRY STATION, BEI TSVILLE, MARYLANDSome recent studies of apple respiration by Hackney (8) implied that the fruit may mediate its oxidations through a phenol oxidase system. In a later study Webster (21,22) could find no evidence for a cytochrome oxidase system in apple tissue. However, more recently a number of reports have appeared which demonstrated cytochrome oxidase activity in apple tissue slices (14) and in cytoplasmic particles from apples (13,16). There are also data showing Krebs cycle activity in cytoplasmic particles from apples (9,18). Nevertheless, a number of workers are still experiencing considerable difficulty in isolating active cytoplasmic particles from apples (15). The difficulties might be traced to characteristics of the apple fruit, such as a highly acid cell sap (pH 3.5), an extremely low concentration of protein (approximately 0.3 %), and a high concentration of polyphenol substances that may injure cytoplasmic particles during homogenization. As a first step in isolating active cytoplasmic particles from such tissues it seemed advisable, as previously noted (13) controlled with a variac. The homogenates were strained through four layers of cheesecloth and centrifuged for 10 minutes at approximately 1,000 X G followed by a high speed centrifugation of the supernatant at about 17,000 X G for 15 minutes. The particles obtained from the high speed centrifugation were washed in 0.25 M sucrose and resedimented at 17,000 X G. The particles were finally suspended in 6 ml of 0.25 M sucrose and 0.001 M adenosine triphosphate (ATP) adjusted to pH 7.0. These suspensions generally had a nitrogen (N) content (N of ATP subtracted) that varied from 250 to 900 Ag/ml depending on the buffer of the homogenizing medium. All operations were carried out in a cold room held at 2 to 40 C.ASSAY PROCEDURES: Spectrophotometric assays were conducted at room temperature (approx 20°C) with a Beckman DU spectrophotometer in cuvettes of

show abstract

Section: Methodsmentioning

confidence: 99%

Oxidative Activity of Cytoplasmic Particles of Apples: Electron Transfer Chain

Lieberman

1960

Plant Physiol.

View full text Add to dashboard Cite

show abstract

“…The results show that the predominant phenolic acid in the fruits of cherry laurel cultivars and the wild form is vanillic acid. Browning of fruits and fruit juices has also been related for a long time to the phenolic constituents (Hulme, 1958). The formation of yellow and brown pigments in fruits and fruit juice is controlled by the levels of phenolic compounds, the presence of oxygen, and the amount of polyphenol oxidase (Coseteng and Lee, 1987).…”

Section: Resultsmentioning

confidence: 99%

Phenolic Acid and Fatty Acid Composition in the Fruits ofLaurocerasus officinalisRoem. and Its Cultivars

Ayaz

Kadıoğlu

Reunanen

et al. 1997

Journal of Food Composition and Analysis

View full text Add to dashboard Cite

“…It is almost 40 years since Kidd and West attempted to explain the climacteric rise in respiration which precedes visible ripening in apples in terms of a change in "organization resistance" or permeability of the tissue (11). This hypothesis, based on studies of changes in membrane permeability, has been revived in recent years and become 1 of the 2 main theories advanced to explain the series of biochemical changes which are now known to be associated with the climacteric in apples as well as various other fruits.…”

mentioning

confidence: 99%

Metabolic Changes in Excised Fruit Tissue. IV. Changes Occurring in Discs of Apple Peel During the Development of the Respiration Climacteric

Hulme¹,

Rhodes²,

Galliard³

et al. 1968

Plant Physiol.

View full text Add to dashboard Cite

Abstract. It is shown that a sequential development of a serie-s of enzyme systems occurs in the peel of the apple as the respiration climacteric develops in the wvhole fruit. The sequence of development of these systems, i.e. acetate incorporation into lipid, production of ethylene, inoorporation of amino acid into protein and, finally, the decarboxylation of added malate (ma,late effect) is the same as that shown earlier for the short term (24 hr) aging of peel discs from pre-climacteric apples. As these systems appear in the initial discs from fruit passing through the climacteric they gradually cease to increase during the 24 hour aging period. Uptake studies show that none of the changes in these systems can be due solely to changes in the permeability of the tissue over the climacteric period. On the basis of these results it is tentatively suggested that the aging of discs from pre-climacteric tissue might provide a model system for a detailed study of the physiological and biochemical changes occurring during the climacteric of apple fruits.It is almost 40 years since Kidd and West attempted to explain the climacteric rise in respiration which precedes visible ripening in apples in terms of a change in "organization resistance" or permeability of the tissue (11). This hypothesis, based on studies of changes in membrane permeability, has been revived in recent years and become 1 of the 2 main theories advanced to explain the series of biochemical changes which are now known to be associated with the climacteric in apples as well as various other fruits. Bain and Mercer (1) found that changes in the inner structure of the chloroplasts had already occurred by the time climacteric rise had begun and as the rise progressed there was also a disorgan,ization of the ultrastrtcture of the protoplasts. Their resuilts were con.sistent witlh ain increase in the permeability of the cells especially in the early stages of the climacteric. Rho(les an-ld WVooltorton (19) slhowed that considerable disorganization of chloroplast lamellae accompaniedl the loss of chlorophyll in the peel of the fruit during the climacteric period. Sacher (25) from his work on the banana concluded that the initiation of permeability changes may be construed as a cause of the onset of the climacteric. At the climacteric peak hiis tissue was "essentially 100 % free space to mannitol, sucrose, fructose, and chloride". In general agreement with this hypothesis, Young and Biale (26) from studies of 32P-uptake by discs of the avocado pear, concluded that the respiratory climacteric is initiated by the failure of the cellular membranes to maintain their permeability characteristics.The other major theory concerning the climacteric originated in the discovery of a net increase in protein (as nitrogenotus material insoltuble in 80 % ethanol) in apples during the climacteric. the increase not taking place under conditions which suppress the development of the climacteric (7). A similar increase in protein was found in avocados and tomatoes by Rowan ...

show abstract

Some Aspects of the Biochemistry of Apple and Pear Fruits

Cited by 121 publications

References 171 publications

Oxidative Activity of Cytoplasmic Particles of Apples: Electron Transfer Chain

Oxidative Activity of Cytoplasmic Particles of Apples: Electron Transfer Chain

Phenolic Acid and Fatty Acid Composition in the Fruits ofLaurocerasus officinalisRoem. and Its Cultivars

Metabolic Changes in Excised Fruit Tissue. IV. Changes Occurring in Discs of Apple Peel During the Development of the Respiration Climacteric

Contact Info

Product

Resources

About