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Page number:71 
Remarks (internal):Optimal growth occurs at 25-28ºC, the minimum at 11-13ºC and the maximum at 41-42ºC (517, 1827), but in some reports these temperatures have been given as 32º, 10º and 44ºC, respectively (261). Optimal growth was obtained at 0.016 atm O2 partial pressure (1428).
Growth occurs on media containing p-hydroxy-benzoic aldehyde (2165), lignin sulphonate (1425) or tannin (1260). A. candidus is reported to use straw lignin (2165), utilize arabinoxylan modestly (1757) and degrade cellulose (4186, 5674), with (NH4)2SO4 as the most suitable N source at a C/N ratio of 10:1 (5675). In stored corn it causes an increase in free fatty acids due to its lipolytic activity (4744). Proteolytic, amylolytic and pectolytic processes have also been studied (1827, 4545). It can oxidize tryptamine to tryptophol (1522) and the conidia can produce D-mannitol from glucose and other sugars (4124). There is evidence showing the production of ethylene (2641), and two antibiotics: chlorflavonin acting against fungi (4042, 4832) and candidulin against (myco)bacteria (512, 5532); other authors, however, have not observed any antibacterial activity (5974). Reports of citrinin (6005) and kojic acid (5278) production are based on misidentifications of A. niveus and a white mutant of A. flavus, respectively (J.C. Frisvad, pers. comm.). Further metabolic products include dechlorochlorflavonin and p-terphenyl derivatives (3597, 3598) which were shown to act on HeLa cells (5689). Various disorders due to A. candidus have been observed in pigs (3932). In mixed culture, A. candidus suppressed growth and aflatoxin production of A. parasiticus (621) and showed antimycotic activity against Aspergillus fumigatus (569). Riboflavin is apparently not produced, contrary to many other Aspergillus species (1620). Significant stimulation of flax seedlings has been observed in greenhouse experiments (1427).
A. candidus shows optimal growth on media with 10% NaCl (1428), it tolerates 20% NaCl (976) or up to 40% sucrose (4001) in nutrient media and 10% CO2 in the atmosphere (4029). Cellulose degradation by A. candidus proved to be highly sensitive to the herbicide paraquat (5676).
 
Description type:General description 
Description:Aspergillus candidus Link 1809 : Fr. Fig. 36.
Descriptions: Raper and Fennell (4744), Subramanian (5626), and Hirayama and Udagawa (2464).
Aspergillus subgen. Circumdati sect. Candidi (= A. candidus group). It differs little from the A. niger group, except for the absence of pigmentation and roughening of the conidia. A. candidus also superficially resembles Fennellia nivea (q.v.) which has much smaller conidial heads.
Colonies relatively slow-growing, reaching 1.5-3.0 cm diam in 14 days at 24-26ºC on CzA but somewhat more rapid with the addition of 20% sucrose, white, at most becoming cream to yellowish cream. Conidiophores typically with large globose vesicles, bearing inflated, club-shaped metulae and narrow phialides. Conidia globose to ellipsoidal, smooth-walled, 2.5-3.5(-4.0) µm diam, uninucleate (6514), the chains sometimes sliming down. Purple or black sclerotia are produced by some isolates.
A. candidus has its main distributional range in subtropical and tropical regions. There are numerous reports from India, where it has been found in cultivated fields (44, 1317, 1519, 4610), grassland (3865, 4933), forest soils (2179, 2186, 4716, 4995), uncultivated soil (4030), lateritic soil, chernozem (5000), black clay (4736), alkaline soil (968), sand dunes (4371), highly saline soils (4477), soils with different water regimes (1315), and mangrove mud (4700); a reduced occurrence in the hot summer months is reported (2179). Records are also available from Bangladesh (2712), Pakistan (4855), Kuwait (4000, 4001), Sri Lanka (4021), South Africa (1415), Somalia (5049), equatorial West Africa (1420), the Chad area and the Sahara (2974, 3415), Libya (4084), Egypt (8, 3993, 4962), Syria (5392), Israel (2764, 2772), Argentina (6402, 6403, 6404, 6405), the Bahamas (4312), New Guinea, the Solomon Islands (5983), China (3475), Central America (1697), Chile (4569), the USSR (1482, 2871, 3850, 4474, 4548), Nepal (1826), and the USA (2482, 3550). It is a rare component of the soil mycoflora in European countries but it is known from soils in Spain (3417, 3447), Italy (1794, 3445), Hungary (1712, 2165), Austria (3413, 3418), Czechoslovakia (1702, 1703), Germany (1424, 1712, 5316), France, Britain (3548), and Ireland (1376). In addition to the Indian records cited above, the fungus has been isolated from forest soils (1712, 2482, 2854, 3447), soils with steppe type vegetation (1702, 3415, 5049), desert soils (2973, 4084), garden compost (1424), peat (1376, 4474), rendzina (3413, 3414), caves and mines (1703, 4312), polluted water (1482), saline soil (8, 4000, 4001), marine environments (4918) and the air (3548). It is remarkable that A. candidus in soil is almost exclusively found either on seeds or in the rhizosphere and not in root-free soil. The fungus occurs on seeds of wheat, oats and barley (57, 1029, 1752, 1757, 2716, 3989, 4038, 4492) of which it inhibits the germination to some degree (4306), mouldy sorghum (795, 3989), corn (3989, 4831), rice (1337, 2297, 2464, 3181), green coffee beans (3302), in the rhizospheres of groundnut (2768, 4735), Trifolium alexandrinum (1963), wheat (45), corn (4555), rice (2712), Abutilon indicum (3864), Cassia occidentalis (6067), Euphorbia spp. at all growth stages (3866), various steppe plants (3376), in the ectomycorrhiza of Corylus avellana (1794), on litter of Pinus ponderosa (681), in a wheat-straw compost (953), rarely on coarse fodder (3258, 4548), most frequently in dough products (2067), also on frozen fruit cakes (3153), nuts and dried fruits (2258, 2572, 6252), various other foodstuffs (4986, 5980), damaged flue-cured tobacco (6282), wood exposed to seawater (4546), fresh water and sewage (1166), pig (5983), rabbit (6085) and vole (IMI, 2338) dung, nests, feathers and pellets of free-living birds (2575), and dead bees (402). Some reports suggest a preferential occurrence in neutral or slightly alkaline habitats (968, 3417, 3445, 4700, 5000, 5049); and it is also found in habitats with temperatures rising to 50-55ºC (5000, 5049, 6273). A. candidus may cause the self-heating of stored wheat grain on which substrate it has a strong competitive ability at very low water potentials (1036, 4744); in vitro optimal growth occurs at -30 bars, minimum moisture requirement about -300 bars water potential (261).
 
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