Toxicological evaluation of some food
    additives including anticaking agents,
    antimicrobials, antioxidants, emulsifiers
    and thickening agents



    WHO FOOD ADDITIVES SERIES NO. 5







    The evaluations contained in this publication
    were prepared by the Joint FAO/WHO Expert
    Committee on Food Additives which met in Geneva,
    25 June - 4 July 19731

    World Health Organization
    Geneva
    1974

              

    1    Seventeenth Report of the Joint FAO/WHO Expert Committee on
    Food Additives, Wld Hlth Org. techn. Rep. Ser., 1974, No. 539;
    FAO Nutrition Meetings Report Series, 1974, No. 53.

    CAROB BEAN GUM

    Explanation

         This substance has been evaluated for acceptable daily intake by
    the Joint FAO/WHO Expert Committee on Food Additives (see Annex 1,
    Ref. No. 19) in 1969.

         Since the previous evaluation, additional data have become
    available and are summarized and discussed in the following monograph.
    The previously published monograph has been expanded and is reproduced
    in its entirety below.

    BIOLOGICAL DATA

    BIOCHEMICAL ASPECTS

         Groups each of eight male Holtzman rats were maintained on a
    purified synthetic diet, or the diet plus 1% cholesterol, or the diet
    plus 1% cholesterol plus 10% carob bean gum, for 28 days. The
    increased liver cholesterol and liver total lipid induced by
    cholesterol feeding was largely counteracted by concurrent feeding of
    carob bean gum (Ershoff & Wells, 1962).

    TOXICOLOGICAL STUDIES

    Special studies

         Eight infants between the ages of two-and-a-half to five months
    were fed meals of sugared milk or sugared milk plus 1% powder
    extracted from carob bean. Addition of the carob bean extract
    supplement did not alter the duration of the gastrointestinal transit
    time of the meal. Physiological aerophobia was markedly suppressed by
    the carob bean extract supplement (Rivier, 1952).

    Short-term studies

    Rat

         A study is under way in which 10 male and 10 female rats per
    group are being fed 1, 2 and 5% carob bean gum (Til & Spanjers, 1973).

    Chickens

         Groups of 20-day-old chicks were fed diets containing 0.25, 0.5,
    1 and 2% carob bean gum for three weeks. Growth depression was dose-
    related and marked at 2% level of intake (Kratzer et al., 1967; Vohra
    & Kratzer, 1964).

    Long-term studies

         None available.

    OBSERVATIONS IN MAN

         A clinical study of a commercial preparation of carob gum as a
    laxative in doses of "two heaping teaspoonfuls" in 56 patients, some
    of whom took the preparation regularly for two years, resulted in no
    untoward effects related to the gastrointestinal tract, and no
    allergic reactions (Holbrook, 1951).

    Comments:

         Carob bean gum (locust bean gum) is used in pharmaceutical
    preparations. There is little evidence on its metabolism and a short-
    term study in rats is in progress. More information on the metabolism
    in other species including man and another short-term study in a non-
    rodent species are required.

    EVALUATION

         Not possible on the data provided.

    REFERENCES

    Ershoff, B. H. & Wells, A. F. (1962) Proc. Soc. Exptl. Biol. Med.,
         110(3), 580-582

    Holbrook, A. A. (1951) Amer. J. dig. Dis., 18, 24

    Kratzer, F. H., Rajaguru. R. W. A. S. B. & Vohra, P. (1967) Poultry
         Sci., 46(6), 1489-1493

    Rivier, C. (1952) Schweiz. Med. Wschr., 82(10), 256-258

    Til, H. P. & Spanjers, M. T. H. (1973) Unpublished report No. 4093
         from TNO

    Vohra, P. & Kratzer, F. H. (1964) Poultry Sci., 43(5), 1164-1170

    See Also:
       Toxicological Abbreviations
       Carob bean gum  (FAO Nutrition Meetings Report Series 46a)
       Carob bean gum (WHO Food Additives Series 15)
       CAROB BEAN GUM (JECFA Evaluation)