Rhizopus

4 Key excerpts on "Rhizopus"

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  Food Technology

  Objective Food Microbiology

  • Suresh Chandra, Ratnesh Kumar, Ruchi Verma(Authors)
  • 2022(Publication Date)
  • NIPA GENX Electronic Resources and Solutions Pvt Ltd.

    (Publisher)

  1. The fungi are usually: a) Parasites or saprophytes b) Lithophytes c) Epiphytes d) Insectivorous 2. The branch of botany under which fungi are studies is known as a) Bacteriology b) Parasitology c) Mycology d) Bryology 3. Rhizopus is also known as a) Grown gall b) Black mould c) Green mould d) Blue mould 4. The fungi are mostly: a) Autotrophic b) Holotrophic c) Chemotrophic d) Heterotrophic 5. The parasitic fungi take their nutrition from their host with the help of: a) Soredia b) Paraphyses c) Haustoria d) Fruiting bodies 6. The importance of study of parasitic fungi is that they are: a) Used as food b) Ornamental c) Causes of diseases d) Condiments 7. The fungi that are used as food are a) Slime mould b) Mushrooms c) Mildews d) Rust and smut 8. Rhizopus belongs to a) Phycomycetes b) Ascomycetes c) Basidiomycetes d) Deuteromycetes 3 Food Microbiology-II 72 Objective Food Microbiology 9. Rhizopus and yeast are a) Autophytic b) Epiphytic c) Parasitic d) Saprophytic 10. Which is an edible fungus a) Agaricus b) Rhizopus c) Puccinia d) Smut 11. Rhizopus, which is saprophytic by nature, is known as a) Rust b) Smut c) Bread mold d) Pond sills 12. The mycelium of Rhizopus is a) Aseptate and Binucleate b) Aseptate and multinucleate c) Septate and nucleate d) None of above 13. Reproduction of Rhizopus is a) Only sexual b) Only asexual c) Vegetative, asexual & sexual d) None of the above 14. The sexual reproductive orgasm in Rhizopus is a) Sporangiophore b) Columella c) Aplanogametangium d) None 15. The Rhizopus in a) Homothallic b) Heterophillic c) Both (a) and (b) d) None 16. The Rhizopus gametes are formed in a) Mycelium b) Sporangiophores c) Suspensor cells d) Gametangia 17. Yeast belongs to class a) Deuteromycetes b) Ascomycetes c) Zygomycetes d) Basidiomycetes 18. The chief characteristics of class Ascomycetes is a) Formation of spores b) Formation of zoospores c) Hypes d) Formation of ascospores 19.

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  Taxonomic Guide to Infectious Diseases

  Understanding the Biologic Classes of Pathogenic Organisms

  • Jules J. Berman(Author)
  • 2019(Publication Date)
  • Academic Press

    (Publisher)

  Most of the pathogenic zygomycotes are noncommensal opportunists. They grow in soil, water, or air, on plants or on dung. Humans are constantly being exposed to their infective spores, by inhalation or by ingestion. Virtually all infections occur in patients who provide these fungi with a physiologic opportunity for growth (e.g., malnutrition, diabetes, advanced cancer, immunodeficiency, or an infection portal such as an indwelling catheter or an intravenous line).

  Zygomycota Mucoromycota Mucormycotina Mucorales Mucoraceae Rhizopus (genus) Mucor (genus) Absidia (genus) Syncephalastraceae Syncephalastrum (genus) Zoopagomycota Entomophthoramycotina Entomophthorales Basidiobolaceae Basidiobolus (genus) Ancylistaceae Conidiobolus (genus)

  The pathogenic members of Class Zygomycota belong to one of the two subclasses: Class Mucorales or Class Entomophthoramycotina. Infection with any zygomycote is known as zygomycosis. When the infectious agent is known to be a member of Class Mucorales, the disease is more specifically known as mucormycosis. Class Mucorales account for the bulk of infections caused by zygomycotes. Regardless of the mucorales species, the clinical infections are similar. Common primary sites of infection are lungs, gastrointestinal tract, kidneys, and skin. Sinus infections, spreading to the nasopharynx, eyes, and brain, seem to have a particular affinity for diabetic individuals. Primary infections tend to be invasive, and may lead to disseminated disease. Rare infectious genera in Class Mucorales, aside from those listed here, have recently been isolated: Cokeromyces, Saksenaea, Apophysomyces, and Chlamydoabsidia [1] (Fig. 6.1 ).

  Fig. 6.1 Mucor pusillus infection of heart valve. Notice wide fungal hyphae, with few or no septations along their lengths. (Source, a public domain image provided by the U.S. Centers for Disease Control and Prevention, and produced by Dr. Libero Ajello.)

  Infections caused by species of Class Zoopagomycota produce somewhat different clinical picture than that of Class Mucoromycota. The zoopagomycoses are most often primary skin infections, and can occur in immune-competent hosts. Infections caused by Genus Basidiobolus often arise on the trunk and thighs. Infections from members of Genus Conidiobolus typically arise on the nose and face [5]

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  Pathogenic Fungi in Humans and Animals

  • D.H. Howard(Author)
  • 2002(Publication Date)
  • CRC Press

    (Publisher)

  The species is treated after Schipper (54), thus including Rh. rhizopodiformis (Cohn) Zopf, Rh. oligosporus Saito, and Rh. chinensis Saito as varieties, which are often recognized at the species level in the medical literature. For differences see Table 7. Rhizopus azygosporus Yuan & Jong, isolated from tempeh in Indonesia, is considered an azygospore- producing intermediate between Rh. microsporus var. rhizopodiformis and var. microsporus. Rhizopus microsporus ranks second after Rh. oryzae as an agent of human mucormycosis, being especially responsible for the cutaneous and gastrointestinal mycoses forms of the disease (14, 57). It is only exceptionally found in cranial (rhinocerebral) mycoses (58). It is also known to be hospital-acquired (59). Polonelli et al. (60) conducted antigenic studies with the Rh. microsporus complex. The azygosporic Rh. azygosporus has been reported from lethal mucormycosis in premature babies (61). Rh. microsporus also occurs often in mammals, particularly pigs and cattle. Rh. schipperae Weitzman et al.: The species is very close to Rh. microsporus var. microsporus, mainly differing in the larger groups (up to 10) of sporangiophores per stolon, the abundant production of chlamydospores (globose to ellipsoid, thin- to thick-walled, up to 20 μ m in diame ter) on all media, the poor production of sporangia (and thus a paler color) and negative mating results with the mating types of Rh. microsporus. ZYGOMYCETES 111 The species was isolated from bronchial wash and lung specimens from a patient with myeloma (62) (Table 7). 2. Mortierellaceae The sporangia are from one- to many-spored and globose. The columella are absent or very small, and never protrude into the sporangium. The mycelium is often unusually fine. Key to the Genera of the Mortierellaceae 1a. Sporangiospores with two vermiform appendages Aquamortierella 1b. Sporangiospores without vermiform appendages 2 2a. Thin-walled sporangia borne in sporocarps Modicella 2b.

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  Food Mycology

  A Multifaceted Approach to Fungi and Food

  • Jan Dijksterhuis, Robert A. Samson, Jan Dijksterhuis, Robert A. Samson(Authors)
  • 2007(Publication Date)
  • CRC Press

    (Publisher)

  Whereas these are valuable properties that may contribute to the evolution of fer-mented foods, it appears that in fermentations where Rhizopus or Amylomyces are present as well, Mucor spp. are not the prime movers of the fermentation. They may, however, contrib-ute in other ways, such as formation of certain flavour compounds or fatty acids (Oxlade, 1990; Agranoff and Markham, 1997). In a com-parison of Amylomyces rouxii and Mucor cir-cinelloides , it was found that the latter accumu-lated glucose less efficiently from rice starch; this was not related to glucoamylase activity but rather to its profuse biomass formation (Dung, 2004). Rhizopus spp. (Schipper and Stalpers, 1984) of importance in food fermentation are R. mi-crosporus and R. oryzae . The latter is mesophilic, forms a variety of enzymes particularly starch degrading enzymes and is encountered in a diversity of amylolytic starters for alcoholic fermentations such as koji, nuruk, chu and murcha (Tamang et al ., 1996; Nout and Aidoo, 2002; Shrestha et al ., 2002); its glucoamylase gene has been brought to expression in Sac-charomyces cerevisiae to facilitate the direct pro-duction of ethanol from raw maize starch (Shigechi et al ., 2004). Whereas fungal starch degradation for winemaking is mainly prac-tised in Asia, the use of Rhizopus spp. was de-scribed as well in a complicated process for making Parakari, an indigenous alcoholic bev-erage made from cassava in Guyana (Henkel, 2005). Rhizopus spp. can produce health-promoting unsaturated fatty acids such as gamma-linolenic acid (GLA) (Liu et al ., 2004). R. oryzae is also used for soybean fermenta-tions, e.g., in tempe manufacture. On the other hand, R. microsporus is thermophilic and pre-fers temperatures ranges from 30-40 °C. Within this species, varieties are distinguished of which R. microsporus var. oligosporus (in short: R. oligosporus ) is best known in relation with the tempe fermentation.

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