Changes in respiration and soluble carbohydrates during the post‐harvest storage of mushrooms (<i>Agaricus bisporus</i>)

Hammond, John B. W.; Nichols, R.

doi:10.1002/jsfa.2740260615

Cited by 149 publications

(107 citation statements)

References 10 publications

Supporting

Mentioning

103

Contrasting

Order By: Relevance

“…The present study has shown that changes in the activity of two other enzymes, considered to be responsible for the carbohydrate supply to the developing sporophore (namely, trehalase and glycogen phosphorylase), also accompany fiushing and exhibit a similar correlation with it. In each case, the enzymes extracted from stage 1 sporophores (Hammond & Nichols, 1975 reach their maximum activity when a flush reaches its peak, as defined by yields of stage 2 to 4 sporophores. Minimum activity corresponds to the period between flushes.…”

Section: Discussionmentioning

confidence: 99%

VARIATIONS IN ACTIVITIES OF GLYCOGEN PHOSPHORYLASE AND TREHALASE DURING THE PERIODIC FRUITING OF THE EDIBLE MUSHROOM AGARICUS BISPORUS (LANGE) IMBACH.

1987

Self Cite

View full text Add to dashboard Cite

SUMMARYActivities of trehalase and glycogen phosphorylase were determined for stage 1 (pin) sporophores of Agaricus bisporus harvested daily throughout several fruiting cycles (flushes). Both enzymes exhibited maximum activity coincident with peak flush, as defined by maximum yield of stage 2 to 4 sporopbores and minimum activity during the interflush periods. Glycogen phosphorylase activity sometimes peaked on more than one occasion during a flush, whereas trehalase gave only a single peak of activity per flush. These results are discussed in relation to metabolic events associated with carbobydrate changes during tbe periodic fruiting cycle of tbis fungus.

show abstract

Section: Discussionmentioning

confidence: 99%

VARIATIONS IN ACTIVITIES OF GLYCOGEN PHOSPHORYLASE AND TREHALASE DURING THE PERIODIC FRUITING OF THE EDIBLE MUSHROOM AGARICUS BISPORUS (LANGE) IMBACH.

1987

Self Cite

View full text Add to dashboard Cite

show abstract

“…Mannitol functions as the endogenous carbon and energy source to enable sporulation of the oocysts outside of the host (2). Similarly, in A. bisporus fruiting bodies, mannitol contributes up to 50% of the dry weight and is believed to be the main source of carbon and energy in the mushroom after harvest (16).…”

mentioning

confidence: 99%

Mannitol Is Required for Stress Tolerance inAspergillus nigerConidiospores

et al. 2003

View full text Add to dashboard Cite

D-Mannitol is the predominant carbon compound in conidiospores of the filamentous fungus Aspergillus niger and makes up 10 to 15% of the dry weight. A number of physiological functions have been ascribed to mannitol, including serving as a reserve carbon source, as an antioxidant, and to store reducing power. In this study, we cloned and characterized the A. niger mpdA gene, which encodes mannitol 1-phosphate dehydrogenase (MPD), the first enzyme in the mannitol biosynthesis pathway. The mpdA promoter contains putative binding sites for the development-specific transcription factors BRLA and ABAA. Furthermore, increased expression of mpdA in sporulating mycelium suggests that mannitol biosynthesis is, to a certain extent, developmentally regulated in A. niger. Inactivation of mpdA abolished mannitol biosynthesis in growing mycelium and reduced the mannitol level in conidiospores to 30% that in the wild type, indicating that MPD and mannitol 1-phosphate phosphatase form the major metabolic pathway for mannitol biosynthesis in A. niger. The viability of spores after prolonged storage and germination kinetics were normal in an mpdA null mutant, indicating that mannitol does not play an essential role as a reserve carbon source in A. niger conidia. However, conidiospores of a ⌬mpdA strain were extremely sensitive to a variety of stress conditions, including high temperature, oxidative stress and, to a lesser extent, freezing and lyophilization. Since mannitol supplied in the medium during sporulation repaired this deficiency, mannitol appears to be essential for the protection of A. niger spores against cell damage under these stress conditions. Polyols or polyhydroxyalcohols are present in all organisms, from bacteria to animals. In particular, plants and fungi are known to accumulate high levels of polyols intracellularly, up to several hundred millimoles per liter. The filamentous fungus Aspergillus niger produces a number of different polyols, including glycerol, erythritol, and D-mannitol (41). The intracellular concentrations of the individual polyols in A. niger depend on growth conditions and developmental stage, suggesting that polyols have important functions in fungal physiology.The hexitol D-mannitol is accumulated by vascular plants (37) and many fungal species (21). In A. niger conidiospores, D-mannitol is the predominant carbon-containing compound and makes up 10 to 15% of the dry weight (41). The metabolic pathway for mannitol biosynthesis in ascomycete and deuteromycete fungi most likely consists of two steps (19) (Fig. 1). Fructose 6-phosphate is reduced to mannitol 1-phosphate by NAD ϩ -dependent mannitol 1-phosphate dehydrogenase (MPD), followed by the dephosphorylation of mannitol 1-phosphate, which is catalyzed by mannitol 1-phosphate phosphatase (MPP), yielding mannitol. The presence of MPD and MPP in several fungi, such as A. niger (22), Aspergillus nidulans (34), and Alternaria alternata (18), has been demonstrated, but these enzymes are also responsible for mannitol biosynthesis in protozoa...

show abstract

“…bisporus, the stipe lengthens and the cap expands to expose the developing gills (Hammond & Nichols, 1975). Treatment with polyoxin D or cycloheximide reduced this expansion ( Table I) ; sporophores treated with antibiotics expanded only some 12 to 13 % over 2 days.…”

Section: Resultsmentioning

confidence: 99%

Inhibition of Growth and Development of Agaricus bisporus by Polyoxin D

Wood¹,

Hammond²

1977

Journal of General Microbiology

View full text Add to dashboard Cite

I N T R O D U C T I O NThe antibiotic polyoxin D specifically inhibits chitin synthase in fungi (Corbett, 1974). The development of sporophores of the basidiomycete Coprinus cinereus has been shown to require chitin synthase activity (Gooday, I972 ; Gooday, de Rousset-Hall & Hunsley, 1976). These authors found that sporophore development of C. cinereus was inhibited by concentrations of polyoxin D similar to those which inhibited the activity of chitin synthase preparations in vitro.The edible mushroom Agaricus bisporus (Lange) Imbach contains chitin in its cell walls (Kreger, 1954;Michalenko, Hohl & Rast, 1976). To determine if chitin synthase activity is involved in mycelial growth and fruit body expansion of A. bisporus, we have examined the effect of polyoxin D on these processes. We have also examined the effect of cycloheximide, a protein synthesis inhibitor. METHODS Organism. Agaricus bisporus strains ~6 2 1and ~6 4 9 were used. These are of direct commercial origin.Assessment of inhibition of colony growth. Cultures of A . bisportts strain ~6 2 1 were inoculated on to malt agar plates (Wood, 1976). Polyoxin D was incorporated into the plates before inoculation by spreading 0-2 ml of sterile filtered solutions of polyoxin D on to the surface of the medium. Concentrations are expressed as those present in the agar. After inoculation the plates were incubated at 25 "C and colony diameters were measured at intervals. Ten replicate plates were measured for each treatment.Treatment of growing and excised sporophores. Growing sporophores were treated by injecting sterile solutions of polyoxin D into the stipe base. Approximately 40 pl containing 200 pg polyoxin D was introduced into the sporophore. Alternatively, sporophores were harvested at about stage 2 of development (Hammond & Nichols, 1976) by cutting across the stipe approximately I cm below the velum. Measurements were made of the stipe length and cap diameter, using calipers. The sporophores were then placed with the cut stipe ends dipping into small beakers containing 2 ml of solutions of polyoxin D at 2,20 or roo pg ml-1, cycloheximide at roo pg ml-l or distilled water. The sporophores and beakers were kept in chambers at 90% relative humidity for 2 days. During this period all of the solution was imbibed. The sporophores were then removed and the cap and stipe were measured again.Chitin content. The treated sporophores were separated into cap, lower stipe and upper stipe tissues. Samples of these were homogenized in distilled water. Duplicate samples of the homogenate were removed and dried to constant weight. Other samples of the homogenate were treated with 10% (w/v) NaOH at roo "C for 30 min and centrifuged at 6000 g for 10 min. The pellets were treated with 2% (vlv) HC1 at 20 "C for I h, centrifuged and then 40-3

show abstract

Changes in respiration and soluble carbohydrates during the post‐harvest storage of mushrooms (Agaricus bisporus)

Cited by 149 publications

References 10 publications

VARIATIONS IN ACTIVITIES OF GLYCOGEN PHOSPHORYLASE AND TREHALASE DURING THE PERIODIC FRUITING OF THE EDIBLE MUSHROOM AGARICUS BISPORUS (LANGE) IMBACH.

VARIATIONS IN ACTIVITIES OF GLYCOGEN PHOSPHORYLASE AND TREHALASE DURING THE PERIODIC FRUITING OF THE EDIBLE MUSHROOM AGARICUS BISPORUS (LANGE) IMBACH.

Mannitol Is Required for Stress Tolerance inAspergillus nigerConidiospores

Inhibition of Growth and Development of Agaricus bisporus by Polyoxin D

Contact Info

Product

Resources

About