GB/T 4789.16-2003 Identification of common toxin-producing molds in food hygiene microbiological examination
Some standard content:
ICS07.100.30
National Standard of the People's Republic of China
GB/T4789.16—2003
Replaces GB/T4789.16—1994
Microbiological examination of food hygiene—Identification of common mycotoxin producing fungi
Microbiological examination of food hygiene-Identification of common mycotoxin producing fungiPromulgated on August 11, 2003
Ministry of Health of the People's Republic of China
Administrative Committee of Standardization of the People's Republic of China
Implementation on January 1, 2004
GB/T4789.16—2003
This standard revise GB/T4789.16—1994 "Microbiological examination of food hygiene—Identification of common mycotoxin producing fungi". Compared with GB/T4789.16-1994, this standard has the following major revisions: The format and text of the standard text are revised in accordance with GB/T1.1-2000. The "equipment and materials" in the original standard are revised and standardized. GB/T4789.16-1994 will be abolished as of the date of implementation of this standard. Appendix A, Appendix B, Appendix C and Appendix D of this standard are informative appendices. This standard is proposed and managed by the Ministry of Health of the People's Republic of China. The drafting unit of this standard is the Institute of Nutrition and Food Safety, Chinese Center for Disease Control and Prevention. The main drafters of this standard are Liu Xingjie, Luo Xueyun, Li Fengqin and Li Yuwei. This standard was first issued in 1984, revised for the first time in 1994, and this is the second revision. 108
1 Scope
Microbiological examination of food hygiene
Identification of common toxin-producing molds
This standard specifies the identification method of common toxin-producing molds commonly found in food. This standard applies to the identification of toxin-producing fungi of the genera Quercus, Moss, Fusarium and other genera. 2 Normative references
GB/T4789.16—2003
The clauses in the following documents become the clauses of this standard through reference in this standard. For all dated references, all subsequent amendments (excluding errata) or revisions are not applicable to this standard. However, the parties who reach an agreement based on this standard are encouraged to study whether the latest versions of these documents can be used. For all undated references, the latest versions are applicable to this standard. GB/T4789.28—2003 Food hygiene microbiology inspection staining method, culture medium and reagents 3 Equipment and materials
Refrigerator 0℃~4℃.
3.2 Constant temperature incubator: 25℃~28℃.
3.3 Microscope: 10×～100×.
3.4 Eyepiece micrometer
3.5 Objective micrometer.
3.6 Sterile inoculation hood.
3.7 Magnifying glass.
3.8 Dropper bottle.
3.9 Inoculation hook needle.
3.10 Separation needle.
3.11 Slide.
2 Cover glass: 18mm×18mm.
3.13 Sterilized knife.
4 Culture medium and reagents
4.1 Lactic acid-phenol solution: in accordance with 3.24 of GB/T4789.28-2003. 4.2 Czapek medium: in accordance with 4.77 of GB/T4789.28-2003. 4.3 Potato-dextrose agar medium: in accordance with 4.78 of GB/T4789.28--2003. 4.4 Potato agar medium: in accordance with 4.79 of GB/T4789.28-2003. 4.5 Corn flour agar medium: in accordance with 4.81 of GB/T4789.28-2003. 109
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5 Operation steps
5.1 Observation of colonies: In order to cultivate complete giant colonies for observation and record, pure culture can be planted on the plate. The method is: turn the plate upside down, inoculate one or three points upward, inoculate two plates for each bacteria, and invert it in a 25℃～28℃ incubator for cultivation. When a small colony just grows, take out a flat blood, cut a 1cm×2cm small piece of the colony and the culture medium with a knife under aseptic operation, place it on the side of the colony, continue to cultivate, and observe it in 5d～14d. This method replaces the small culture method and can directly observe the fruiting body attachment state. 5.2 Slant observation: Inoculate pure culture of mold by streaking (Aspergillus, Penicillium) or spotting (Streptomyces or other fungi) on the slant, culture for 5-14 days, observe the colony morphology, and at the same time, place the culture tube under a microscope and use a low-power microscope to directly observe the morphology and arrangement of spores. 5.3 Slide preparation: Take a glass slide and add a drop of lactic acid-phenol solution, use an inoculation needle to hook a small piece of mold culture, place it in lactic acid-phenol solution, use two separation needles to tear the culture into small pieces, cut and apply to avoid destroying the mold structure; then add a cover glass, if there are bubbles, heat them on an alcohol lamp to remove them. It is best to operate in an inoculation hood when preparing slides to prevent spores from flying. 5.4 Microscopic examination: Observe the morphology and characteristics of the hyphae and spores of the mold, the arrangement of the spores, etc., and make detailed records. 5.5 Report: According to the colony morphology and microscopic examination results, refer to the following morphological descriptions and retrieval tables of various molds to determine the name of the strain. 6 Morphological characteristics of various molds
6.1 Aspergillus
The mold-producing fungi of this genus mainly include Aflatoxin, Aspergillus parasiticus, Aspergillus versicolor, Aspergillus nidulans and Aspergillus ochraceus. The metabolites of these molds are aflatoxin, versicolor and ochraceus. The colors of Aspergillus are diverse and relatively stable. The vegetative mycelium is composed of branched hyphae with transverse septa, which are colorless or brightly colored, some of which are buried and some of which are aerial. Conidiophores are mostly without transverse septa, smooth, rough or with pitting. The top of the stalk is enlarged to form a club-shaped, elliptical, hemispherical or spherical apical capsule, on which one or two layers of peduncles grow. When there are two layers, the lower layer is the peduncle base, and two or more peduncles grow on each peduncle base. A string of conidia grows successively from the top of each peduncle. The structure of a head composed of the apical capsule, pedicels and conidial chains is called a conidial head. Conidial heads have various colors and shapes, such as spherical, radial, club-shaped or straight columnar. Only a few species of the genus A. flavus form a sexual stage and produce closed closed shells. Some species produce sclerotia or sclerotial structures. A few species can produce shell cells of different shapes.
6.1.1 A. flavus
Belonging to the A. flavus group, the colony grows rapidly on Czapek agar medium, with a diameter of 3cm~4cm or 4cm~7cm in 10d~14d. It is yellowish at first, then turns yellow-green, and darkens in color after aging, flat or with radial grooves, and the reverse side is colorless or brownish. Observation under a low-power microscope shows that the conidial heads are loose and radial, and then become loose and columnar. Conidiophores mostly grow from the matrix and are generally less than 1mm in length. Some hyphae produce brownish sclerotia. Microscopic observation of the slides shows that the conidiophores are extremely rough, with a diameter of 10μm-20μm. The apical capsule is flask-shaped or nearly spherical, with a diameter of 10μm-65um, usually 25um-45um. All the apical capsules are attached with peduncles, which are single-layered, double-layered, or single-layered and double-layered on a apical capsule. The peduncles are (6μm-10μm)×(4μm-5.5μm), and the peduncles are (6.5μm-10μm)×(3μm-5μm). Conidia are spherical, nearly spherical, or slightly pear-shaped, 3μm-6μm, and rough (see Figure 1). Huangquwu produces aflatoxin, which can cause acute poisoning and death in animals. Long-term consumption of food containing trace amounts of aflatoxin can cause liver cancer.
1—Conidiophore head of a double-layered pedicel;
2———Conidiophore head of a single-layered pedicel; 3—base of conidiophore (foot cell); 4—fine structure of a double-layered pedicel;
5—conidia.
Figure 1 Aspergillus flavus
GB/T4789.16—2003
6.1.2 Parasiticus (A, parasiticus) also belongs to the Aspergillus flavus group. The colony is 2.5cm to 4cm in size after 8d to 10d, flat or with radial grooves, yellowish when young, dark green when old, and cream to light brown on the reverse side. Under low-power microscope, conidia heads are loosely radial, with a diameter of 400um to 500μm. Conidiophores vary in length, generally 200μm to 1000μm. Microscopic examination of slides shows that conidiophores are smooth or rough, 10μm to 12μm wide near the apical capsule, which is nearly spherical or flask-shaped or rod-shaped, with a diameter of 20μm to 35μm. The pedicels are single-layered, (7μm to 9μm) × (3μm to 4μm), and arranged closely. Conidia are spherical, extremely rough, with small spines, and a diameter of 3.5μm5.5μm, no reports of producing sclerotia. All strains of parasitic mold can produce aflatoxin. 6.1.3 Aspergillus versicolor belongs to the Aspergillus versicolor group. Colony growth on Czapek agar medium is limited, with a diameter of 2cm to 3cm at 14 days, velvety, flocculent or both. The color changes are quite wide, and different strains may be light green, gray-green, light yellow or even pink locally, and the reverse side is nearly colorless to yellow-orange or rose-colored. Some colonies have colorless to purple-red droplets. Conidial heads are loose and radial, with a size of 100um to 125um. Conidiophores can be up to 500μm~700um in length and 12μm~16um in width, smooth, colorless or slightly yellow. The apical capsule is semi-elliptical to hemispherical, with small stalks on the upper half or three-quarters. The pedicel is double-layered, the pedicel base is (5.5μm8μm)×3μm, the pedicel is (5μm～7.5μm)×(2μm~2.5pm), the conidia are spherical, rough, and the diameter is 2.5um~3μm or slightly larger. Some strains produce spherical shell cells (see Figure 2).
Aspergillus versicolor produces versicolor toxin, which causes liver and kidney damage and can cause liver tumors. 111
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One conidial head:
One conidia;
One shell cell.
6.1.4 Aspergillus nidulans
Figure 2 Versicolor dance
Belongs to the Aspergillus nidulans group. The colony grows fast, with a diameter of 5cm~6cm in 14 days, velvety, green, and some strains appear yellow-brown due to the production of more closed thecae, and the reverse side is purple-red. The conidial head is short columnar, (40μm~80μm)×(25μm~40μm). The conidiophore is extremely short, often curved, generally 75μm~100um, 3.5μm~5μm in diameter near the apical capsule, brown, and smooth wall. The apical capsule is hemispherical, with a diameter of 8μm~10μm. The pedicel is double-layered, with a pedicel base of (5μm~6μm)×(2μm~3μm), and a pedicel of (5μm~6μm)×(2μm~2.5μm). The conidia are spherical, rough, and 3um~3.5μm in diameter. The closed thecae is spherical, dark purple-red, and 135μm~150μm in diameter. Ascospores are biconvex, purple-red, about 5μm×4μm, with two cockscomb-like protrusions. The closed shell is surrounded by a layer of shell cells, which are light yellow, spherical, thick-walled, and about 25μm in diameter (see Figure 3). Aspergillus nidulans produces Aspergillus variegatus.
Conidia head,
Foot cell,
One shell cell.
Figure 3 Aspergillus nidulans
6.1.5 Aspergillus suis (A.ochraceus)
GB/T4789.16-—2003
Belongs to the group of Aspergillus ochraceus. The colony growth on Czapek agar medium is slightly limited, with a diameter of 3cm~4cm in 10d~14d, brown or light yellow, the hyphae in the matrix are colorless or have varying degrees of yellow or purple, and the reverse side is yellow-brown or green-brown. The conidia head is spherical when young, and splits into 2 or 3 columnar forks when old. The conidiophore is 1mm~1.5mm long, 10μm~14μm in diameter, yellowish, extremely rough, and has obvious pitting. The apical capsule is spherical, with a diameter of 30μm~50μm or larger. The pedicels are double-layered and densely attached to the entire surface of the apical capsule. The conidia are spherical to nearly spherical, with a diameter of 2.5μm~3μm or larger, and are often slightly rough. Some strains produce more sclerotia, which are white at first and light purple when old, spherical, ovoid or cylindrical, with a diameter of up to 1mm (see Figure 4). Aspergillus ochraceus produces ochratoxin, which is a strong kidney and liver toxin. 101
1-conidial head;
2-conidiophore.
Figure 4 Aspergillus
6.2 Penicillium
This genus is toxic, mainly including yellow-green Penicillium, citricarcin, arc Penicillium, unfolded Penicillium, pure green Penicillium, red-green Penicillium, purple Penicillium, Icelandic Penicillium and wrinkled Penicillium. The metabolites of these molds are yellow-green penicillin, drosopenicillin, arc-azoic acid, drosopenicillin, erythropenicillin, yellow-sky-jing, cyclochlorin and wrinkled Penicillium.
The vegetative mycelium of Penicillium is colorless, light or brightly colored, with transverse septa, or is ambush or partially ambush or partially aerial. Aerial hyphae are densely felted, loose or partially formed into hyphal cords. Conidiophores are produced from the subducted or aerial hyphae, slightly perpendicular to the hyphae (except for some species, they do not have foot cells like Aspergillus), standing alone or in a certain degree of aggregation or even dense into a certain hyphae bundle, with septa, smooth or rough. The tip has a broom-like branching wheel, called a broom. The broom is composed of a single wheel or two to multiple branching systems, symmetrical or asymmetrical, and the last branch is the cell that produces spores, called a peduncle. The cell on which the peduncle is attached is called the peduncle base, and the cell that supports the peduncle base is called the secondary branch. The peduncle produces conidia by the method of separation, forming an unbranched chain. The conidia are spherical, elliptical or short columnar, smooth or rough, and most of them are blue-green when growing, sometimes colorless or light-colored in other species, but never dirty black. A few species produce closed shells, or have loose and soft structures, forming asci and sporozoites quickly, or have a hard texture like sclerotia and mature slowly from the center to the outside. There are also a few species that produce sclerotia.
6.2.1 Penicillium citreoviride (P.citreoviride), synonym: Penicillium toxicarum (P.toxicarum) belongs to the monorod group, the recumbent Penicillium system. The colony growth is limited, 10d~12d diameter 2cm~3cm, the surface is wrinkled, some are convex or concave in the center, light yellow-gray, only slightly green, the surface is velvety or slightly flocculent, the vegetative hyphae are thin, yellowish. There is little or no exudate, sometimes lemon yellow, slightly musty. The reverse side and culture medium are bright yellow. Conidiophores grow from hyphae closely attached to the surface of the substrate, generally (50μm~100um)×(1.6μm~2.2μm), with smooth walls. Most of the branches are single-rod, and occasionally there are primary and secondary branches. Conidia113
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The spore chains are roughly parallel or slightly spread out. The pedicels are tightly clustered, 8 to 12 in number, mostly (9μm12μm)×(2.2μm~2.8μm). Conidia are spherical, 2.2um～2.8μm, with thin walls, smooth or nearly smooth, and with obvious spore septa when in chains (see Figure 5). The metabolite of Penicillium citrinum is citrinum citrinum, which is a 1
branch;
conidia.
-A very strong neurotoxin.
Figure 5 Penicillium citrinum
6.2.2 P. citrinum
Belongs to the asymmetric group, the subgroup of Penicillium velutipes, and the Penicillium citrinum system. The colony grows in a limited area, with a diameter of 2cm~2.5cm in 10d~14d, with radial grooves, most strains are velvety, others are flocculent, and green. The reverse side is yellow to orange, the culture medium is similar in color or pink, and the exudate is light yellow. Under a low-power microscope, the conidial chain is a clear dispersed column. Most conidiophores grow from the matrix, and some grow from the aerial hyphae in the center of the colony, generally (50μm~200μm)×(2.2μm~3μm), with smooth walls, and generally unbranched. The broom-like branches are composed of 3~4 whorled and slightly scattered peduncles, (12um~20um)×(2.2μm~3μm), and each peduncles is clustered with 6~10 slightly dense and parallel peduncles, (8μm~11μm))×(2μm~2.8μm). Conidia are spherical or nearly spherical, with a diameter of 2.2μm~3.2um, smooth or nearly smooth (see Figure 6). Citrus citrinin produces citrinin, a strong kidney toxin.
1 Common shape;
conidia.
Figure 6 Citrus citrinin
6.2.3 Penicillium cyclopium belongs to the asymmetric Penicillium group, the fascicular Penicillium subgroup, and the cyclopium Penicillium system. The colony grows rapidly, with a diameter of 4.5cm~5cm in 12d~14d, 114
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road belt radial wrinkles, or ring lines appear after aging, dark blue-green, with a white edge of 1mm~2mm wide during the growth period, velvety or powdery texture, but in the younger areas it is significantly fascicular, with no or more exudate, and light color. The reverse side is colorless or yellowish at first, then turns orange-brown. The branches are usually asymmetrical, dense, often with three layers of branches, about 50um to 60μm, with entangled conidial chains on them. Conidiophores are mostly (200um to 400μm) × (3um to 3.5μm), typically rough, but some strains are nearly smooth. Secondary branches (15μm to 30μm) × (2.5um to 3.5μm). Stem base (10μm to 15μm) × (2.5μm to 3.3μm). Pedicels are arranged in whorls of 4 to 8, (7μm to 10μm) × (2.2μm to 2.8μm). Conidia are mostly nearly spherical, 3μm to 4μm, smooth or slightly rough (see Figure 7). The metabolic product of Arc Penicillium is Arcazoic acid, which is a neurotoxin. Figure 7 Broom branches and conidial chains of Arc Penicillium 6.2.4 Island Penicillium (P. islandicum)
Belongs to the bi-rotational symmetrical Penicillium group, the funicular Penicillium system. On Czapek agar medium, the colony grows in a limited, dense cluster, and is a mixture of orange, red and dark green. The reverse side is turbid orange to red, turning to turbid brown. Under a low-power microscope, the conidial chain is entangled in a chain, the conidiophores are short, 50μm to 75μm long, growing from aerial hyphae or hyphal cords, with smooth walls, and the broom branches are typically symmetrical and bi-rotational, slightly short, and some of the peduncles suddenly become pointed, (7μm~9μm)×2μm. Conidia box is round, smooth, (3μm~3.5μm)×(2.5μm~3μm)) (see Figure 8). Penicillium islandensis produces Huangtianjing and cyclochlorine, both of which are liver toxins that can cause liver damage in animals and can cause liver tumors. Broom-shaped branches;
2-conidia.
Figure 8 Penicillium islandensis
6.2.5 Expand Penicillium (P.patulum), synonym: Penicillium urticae (P.urticae) belongs to the asymmetric Penicillium group, the fascicular Penicillium subgroup. On Czapek agar medium, the colony grows locally, with a diameter of 2cm~2.5cm in 12d~14d, most of them have radial grooves, steep edges, slightly convex in the center, and granular surface. Some have obvious hyphae bundles at the edge, while others are flocculent and thick. Gray-green to bright gray. Some strains produce nearly colorless exudate with no obvious odor. The dark yellow on the reverse side gradually changes to orange-brown or even reddish brown, slightly diffused in the culture medium. The broom-like branches are loose and spread, with 3 to 4 layers of branches, and their size and complexity vary greatly, generally 40μm~50μm, and the limit is 20μm~80μm. The conidia chain is slightly spread out, up to 50μm100μm. Some conidiophores are solitary, and some are gathered into bundles, mostly curved, with smooth walls, generally (400μm～520μm)×(3μm～4μm). The secondary branches 115
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spread out, mostly (15μm~20μm)×(3μm~3.5μm). The peduncle base is short, mostly (7μm~9μm)×(3μm3.5μm). The stalks are short, (4.5μm~6.5um)×(2μm~2.5μm), 8~10 densely clustered. Conidia are elliptical, later becoming nearly spherical, with a long axis of 2.5μm~3μm, smooth (see Figure 9). The expanded penicillium produces patulin, which can cause poisoning and death in animals. Repeated subcutaneous injection of patulin can cause sarcomas at the injection site. Patulin is also a neurotoxin. n
Figure 9 The broom branches and conidia chains of the expanded penicillium 6.2.6 Pure green Penicillium (P. viridicatum) belongs to the asymmetric Penicillium group, the fascicular Penicillium subgroup, and the pure green Penicillium system. The colony grows in a limited area, with a diameter of 2.5cm~3.5cm at 12d~14d, bright yellow-green, sometimes with a narrow blue-green band adjacent to the inner side of the white edge, very thick, usually prominently granular, and turns turbid brown in old age. The reverse side is pure light yellow to pure brown. The broom branches normally have three layers of branches, and often the secondary branches and the base of the peduncle grow at the same height. Most of the conidiophores are 3.5μm~4.5μm in diameter, but sometimes up to 6μm, rough to very rough. The pedicels are (7μm~10μm)×(2.5μm~3μm). Conidia are elliptical, up to 4.5μm×3.3μm, or subspherical, about 3.5μm in diameter, slightly rough, in entangled chains or indeterminate straight columns (see Figure 10). Pure green berries produce ochratoxins and citrinin. 1-branch,
one conidia.
Figure 10 Pure green Penicillium
6.2.7 Penicillium rugulosum (P.rugulosum) GB/T4789.16—2003
Belongs to the symmetrical two-round Penicillium group, the rugulosum group. Colony growth is limited, 1.0cm to 1.5cm in diameter at 12d to 14d, pubescent to somewhat flocculent, dark green then slightly gray. The reverse side is initially colorless, slowly turning dark to orange dots and blocks, especially at the edges when cultured on slant surfaces. Most of the cladonia are typical, but often irregular. The pedicels vary in length. Conidiophores are smooth, 2.5μm to 3μm in diameter. Pedicels (10um to 12μm) × (1.8μm to 2μm). Conidia are oval, significantly rough, (3μm to 3.5μm) × (2.5μm to 3μm), forming entangled chains (see Figure 11). Corrugated penicillin produces corrugated penicillin, a liver toxin. 00
Figure 11 Broom branches and conidia of Penicillium rugosum 6.2.8 Penicillium purpurogenum belongs to the symmetrical two-round Penicillium group and the purpurogenum system. The colony growth is slightly limited, with a diameter of 1.5cm~2.5cm in 12d~14d, velvety or slightly flocculent; there are many spores, which are dark green on the yellow to orange-red mycelium, and then turn into dark dark green. The reverse side is dark red to purple-red and diffuses in the culture medium. Conidiophores mostly grow from the matrix, (100μm~150um)×(2.5μm~3.5um), and those that branch out from aerial hyphae are shorter and smoother. The broom branches are typical two-round symmetrical and compact. The peduncle base is 5~8 whorls, (10μm~14μm)×(2.5μm~3μm). The pedicels are slender, pointed at the end, and 4 to 6 are in a tight and parallel cluster, (10μm~12μm)×(2μm~2.5um). Conidia are elliptical to nearly spherical, with thick walls. Most strains are rough, occasionally smooth, (3μm～3.5μm)×(2.5μm~3μm) (see Figure 12).
Red Penicillium (P.rubrum) is very similar to purple Penicillium, the difference is that it is lighter gray-green, and the conidia are smooth and almost spherical.
Purple Penicillium and red Penicillium both produce red Penicillium toxin, which is a liver toxin. 117
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1,2——Branches and conidia of purple Penicillium; broom-like branches and conidia of red Penicillium. 3
6.3 Fusarium
The toxin-producing fungi of this genus mainly include Fusarium graminearum, Fusarium moniliforme, Fusarium trilineum, Fusarium pearsporum, Fusarium pseudocladosporium, Fusarium oxysporum, Fusarium solani and Fusarium equisetum. The metabolites of these fungi are trichothecenes, zearalenone and butenolide. Www.bzxZ.net
On potato-glucose agar or Czapek medium, aerial hyphae are well developed, 0.5cm~1.0cm high or 0.3cm~0.5cm low, or 0.1cm~0.2cm low, sparse aerial hyphae, or even completely absent, and the myxospore layer is directly produced by the matrix hyphae, containing a large number of conidia. Most species have small conidia usually in pseudocapital shape, less in chain shape, or both pseudocapital and chain shape. Small conidia grow on branched or unbranched conidiophores, and have various shapes, such as ovate, pear-shaped, elliptical, oblong, fusiform, lanceolate, sausage-shaped, columnar, conical, comma-shaped, round, etc. There are 1 to 2 (3) septa, and usually the amount of small conidia is greater than that of large conidia. Large conidia are produced on the short claw-like protrusions of the hyphae or on the conidiophores, or in the myxospores; large conidia have various shapes, such as sickle-shaped, linear, fusiform, lanceolate, columnar, sausage-shaped, coiled worm-shaped, eel-shaped, curved, straight or nearly straight. The apical cells have various shapes, such as short beak-shaped, conical, hook-shaped, linear, columnar, gradually narrowing or suddenly shrinking. Aerial hyphae, stroma, myxospores, and sclerotia can be various colors, and the matrix can also be dyed in various colors. Thick-walled spores are interstitial or terminal, solitary or multiple in a spore or in a nodular form, sometimes also in the spore chamber of a large conidia, colorless or with various colors, smooth or rough. Some species of the genus Fusarium only produce mycelium when they are first isolated, and it is often necessary to induce the production of normal large conidia for identification. Therefore, sugar-free potato agar medium or Czapek medium must be inoculated at the same time. 6.3.1 F. moniliforme Aerial hyphae on potato-glucose agar medium are cotton-like, spreading, 0.2 cm to 0.8cm, some strains are flat or partially sunken, and the test tube wall or the center of the colony has a certain degree of rope-like or bundle-like tendency. The color of aerial hyphae varies with the strain and culture medium: white, light pink, lavender. The reverse side of the matrix is lighter yellow, ochre, purple-red or even blue, or colors between them. Wild-type strains generally produce spores well. A layer of slightly reflective, loose fine powder on the aerial hyphae layer is the spores scattered in piles. Some strains produce pink or pink-cinnamon sticky spores in the center of the colony, while some strains are dark blue. The sticky spores contain a large number of small conidia and a large number of large conidia.
The small conidia are oval, spindle-shaped, ovate, pear-shaped, and sausage-shaped. Transparent, single cell or with 1-2 septa, straight or slightly curved, [3μm~7 (~14)μmJ×(2μm~4.8μm) in liquid culture, the largest is (9μm~18μm)×(2.5μm~6μm)]. Small conidia are in clusters or pseudo-capital (see Figure 13). Large conidia are sickle-shaped, spindle-shaped, club-shaped, linear, straight or slightly curved. The spores are narrow at both ends or uniform in thickness, or one end is sharper, 118
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