WORLD HEALTH ORGANIZATION

    WHO Food Additives Series 1972, No. 1




    TOXICOLOGICAL EVALUATION OF SOME 
    ENZYMES, MODIFIED STARCHES AND 
    CERTAIN OTHER SUBSTANCES




    The evaluations contained in this publication were prepared by the
    Joint FAO/WHO Expert Committee on Food Additives which met in Rome,
    16-24 June 19711





    World Health Organization

    Geneva

    1972





                   

    1 Fifteenth Report of the Joint FAO/WHO Expert Committee on Food
    Additives, Wld Hlth Org. techn. Rep. Ser., 1972, No. 488; FAO
    Nutrition Meetings Report Series, 1972, No. 50.

    The monographs contained in the present volume are also issued by the
    Food and Agriculture Organization of the United Nations, Rome, as FAO
    Nutrition Meetings Report Series, No. 50A

    (c) FAO and WHO 1972


    MICROBIAL RENNET

    Biological data

    Source

    This enzyme preparation is prepared from the species Endothia
    parasitica.

    Acute toxicity

    Data are available for some commercial preparations.

                                                                     

    Animal   Route         LD50            Reference
                     (mg/kg body-weight) 
                                                                     

    mouse    oral          >5 000          Delahunt & Stebbins, 1965
             I.v.             820          Delahunt & Stebbins, 1965

    rat      oral          >2 000          Delahunt & Stebbins, 1965
             I.v.             544          Delahunt & Stebbins, 1965
                                                                     

    Short-term studies

    Rat

    Four groups of 10 male and 10 female rats received daily in their diet
    for one year either 0, 8, 16 or 40 mg/kg body-weight of microbial
    rennin.  No adverse effects compared with controls were noted with
    regard to survival, appearance, growth rate, food consumption,
    haematology, urinalysis, serum chemistry, liver triglycerides, organ
    weights, gross and histopathology (Delahunt & Stebbins, 1965).

    Dog

    Four groups of 3 male and 3 female beagles received daily for one year
    an oral capsule with 0, 8, 16 or 40 mg/kg body-weight of microbial
    rennin.  There was no difference between controls and test groups
    related to the administration of the test compound as regards
    survival, appearance, behaviour, body-weight, haematology, urinalysis,
    serum chemistry, serum electrophoresis, neurological and
    ophthalmological examination, organ weights, gross and histopathology
    (Delahunt & Stebbins, 1965).

    Long-term studies

    None available.

    Comments

    The studies extending over 1 year in the rat and dog are available for
    evaluation and do not reveal any adverse effects at levels up to 40
    mg/kg body-weight.  They are not sufficiently long to reveal possible
    chronic effects although the levels used would have revealed any
    deleterious effects due to mycotoxins.  Because it is conceivable that
    undetected chronic effects could occur, further tests are necessary.

    EVALUATION

    Temporarily not limited.*

    Further work required by 1974

    Two year study in rats.

    REFERENCE

    Delahunt, C. S. & Stebbins, -. (1965) Unpublished report

                   

    *Except for good manufacturing practice.
    

    See Also:
       Toxicological Abbreviations
       Microbial rennet (WHO Food Additives Series 1)
       Microbial rennet (WHO Food Additives Series 1)