The invention comprises amides of citric acid having as part of the amide group a residue of an alkylene diamine further substituted at one nitrogen atom by an aliphatic hydrocarbon group containing 10 to 22 carbon atoms, the remaining carboxyl groups of the compound optionally being acylated with an amine or hydrazine. The amide may have the formula: <FORM:0944515/C2/1> where R1 is an aliphatic hydrocarbon group of 12 to 18 carbon atoms, R2 is a non-cyclic amine or hydrazine group linked at one nitrogen atom to the citric acid residue and, when it is a di- or polyamine, may be linked at a second nitrogen atom to form an amide group wit a further citric acid residue, m and n are each 1, 2 or 3 the sum (m+n) being 3 or 4; there may be 2 to 6 methylene groups in the diamine radical.  The amides are prepared by reactin in stoichiometric proportions citric acid with an alkylene diamine substituted with a hydrocarbo radical in a solvent, e.g. xylene, with heating and in the presence of boric acid or toluene sulphoni acid, the product being reacted further with an amine or hydrazine, if desired, under similar conditions.  The amides may be used to disinfect and preserve materials, especially those containing proteins, e.g. casein.  In examples citric acid is reacted with N-dodecyl trimethylene diamine to obtain compounds of formulae: <FORM:0944515/C2/2> and <FORM:0944515/C2/3> and the products are reacted with ethanolamine to obtain products of formulae: <FORM:0944515/C2/4> <FORM:0944515/C2/5> <FORM:0944515/C2/6> with aminoethyl ethanolamine to obtain compounds of formula: <FORM:0944515/C2/7> <FORM:0944515/C2/8> with hydrazine hydrate to obtain a compound of formula: <FORM:0944515/C2/9> with N:N dimethyltrimethylene diamine to obtain: <FORM:0944515/C2/100> with ethylene diamine to obtain: <FORM:0944515/C2/111> with diethylene triamine to obtain: <FORM:0944515/C2/122> A mixture of N-octadecyl trimethylenediamine and N-hexadecyl trimethylene diamine is reacted with citric acid to form compounds of formulae: <FORM:0944515/C2/133> <FORM:0944515/C2/144> where R is an aliphatic hydrocarbon residue with 16 to to 18 carbon atoms.ALSO:Paints, varnishes, lacquers, shampoos and detergents contain amides of citric acid having as part of the amide group a residue of an alkylene diamine further substituted at one nitrogen atom by an aliphatic hydrocarbon group, the remaining carboxyl groups of the compound optionally being acylated with an amine or hydrazine. The amide may have the formula <FORM:0944515/C3/1> where R1 is an aliphatic hydrocarbon group of 12 to 18 carbon atoms, R2 is a non-cyclic amine or hydrazine group linked at one nitrogen atom to the citric acid residue and, when it is a di- or polyamine, may be linked at a second nitrogen atom to form an amide group with a further citric acid residue, m and n are each 1, 2 or 3, the sum (m+n) being 3 or 4, there may be from 2 to 6 methylene groups in the diamine. Theamides have anti-bacterial activity.  In examples, shampoo solutions are prepared containing the acetates of the compounds of formulae <FORM:0944515/C3/2> a condensation product of dodecyl mercaptan with ethylene oxide, lactic acid, ricinoleic acid and a condensation product of hexamethylene diisocyanate with a reaction product of oleyl alcohol and ethylene oxide; detergent solutions are prepared containing the compound of formula <FORM:0944515/C3/3> and reaction products of ethylene oxide with iso-octylphenol, with nonylphenol and with octadecyl alcohol; colour pastes contain titanium dioxide, copper phthalocyanine, casein, water and the compound of formula <FORM:0944515/C3/4>ALSO:Bactericidal and fungicidal compositions contain amides of citric acid having as part of the amide group a residue of an alkylene diamine further substituted at one nitrogen atom by an aliphatic hydrocarbon group, the remaining carboxyl groups of the compound optionally being acylated with an amine or hydrazine. The amide may have the formula <FORM:0944515/A5-A6/1> where R1 is an aliphatic hydrocarbon group of 12 to 18 carbon atoms, R2 is a non-cyclic amine or hydrazine group linked at one nitrogen atom to the citric acid residue and, when it is a di-or polyamine, may be linked at a second nitrogen atom to form an amide group with a further citric acid residue, m and n are each 1, 2 or 3 the sum (m + n) being 3 or 4, there may be from 2 to 6 methylene groups in the diamine.  The amides may be used to disinfect and preserve materials, especially those containing proteins, e.g. casein.  In examples compounds of formul  <FORM:0944515/A5-A6/2> are used to destroy bacteria and inhibit the growth of fungus in aqueous solutions containing casein, sodium tetraborate, glucose broth, and various culture solutions and beer wortagar; a deodorizing stick is prepared from ethanol, sodium stearate and the acetate salt of the compound of formula <FORM:0944515/A5-A6/3>ALSO:Substances are preserved against bacterial and fungal attack by contacting them with amides of citric acid having as part of the amide group a residue of an alkylene diamine further substituted at one nitrogen atom by an aliphatic hydrocarbon group containing 10 to 22 carbon atoms, the remaining carboxyl groups optionally being acylated with an amine or hydrazine. The amide may have the formula <FORM:0944515/A1-A3/1> where R1 is an aliphatic hydrocarbon group of 12 to 18 carbon atoms, R2 is a non-cyclic amine or hydrazine group linked at one nitrogen atom to the citric acid residue, and, when it is a di- or polyamine, may be linked at a second nitrogen atom to form an amide group with a further citric acid residue, m and n are each 1, 2 or 3, the sum (m + n) being 3 or 4; there may be 2 to 6 methylene groups in the diamine radical.  The amide may be used to preserve foodstuffs, glues, textile finishing agents, paints, varnishes, lacquers, dyes, printing pastes, cellulose, paper and especially materials containing proteins, e.g. solutions containing casein.