AU609755B2 - Enzymatic dishwashing and rinsing process - Google Patents

Description

i Li

AUSTRALIA

PATENTS ACT 1952 COMPLETE SPECIFICATION Form

(ORIGINAL)

FOR OFFICE USE 609755 Short Title: Int. Cl: Application Number: Lodged: Complete Specification-Lodged: Accepted: Lapsed: Published: i i ,<:umn t cV. ':i.fVs cthe amendments mid.e uid. r Section 49 and is orwrtA ifO printing -jccr -l m lSel -atf6Kti^j L 1

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Priority: Related Art: TO BE COMPLETED BY APPLICANT Name of Applicant: Address of Applicant: t c 0C UNILEVER PLC UNILEVER HOUSE

BLACKFRIARS

LONDON EC4

ENGLAND

Actual Inventor: Address for Service: CLEMENT HACK CO., 601 St. Kilda Road, Melbourne, Victoria 3004, Australia.

Complete Specification for the invention entitled: ENZYMATIC DISHWASHING AND RINSING COMPOECITIO- p~nC-.es The following statement is a full description of this invention including the best method of performing it known to me:- .I--~-r^lrir~nwlar-r~irr~;r v rrr~,.rl -iiiiii--I-- ~sk~ L. cc c C c t C oe o 0 0e o 00 O 4r 0 00c *t 0 0 00 *o 0 1A The present invention relates to a process for machine dishwashing or rinsing, using a composition comprising lipolytic enzymes.

Enzymatic dishwashing compositions have been proposed in the art. As enzymes, mainly amylases and/or proteases have been proposed for inclusion in dishwashing compositions. Lipases have also been suggested, but have received far less attention then the amylases and/or proteases. Dishwashing compositions, in particular machine dishwashing compositions, which are used in the main wash step of a machine dishwashing operation, have in general a satisfactory cleaning performance. However, frequently the articles cleaned with such products still do not have a satisfactory visual appearance after rinsing and drying, showing film or spots. Some main wash liquor is usually carried over from the main wash step to the rinse step, causing some deposition of soil resulting in insoluble calcium salts on the articles to be rinsed, which results in visible film or spots on the articles when they are dry. In particular with glass articles, this causes an unsightly visual appearance.

We have now found that the addition of lipases to a main wash dishwashing composition or to a rinse composition significantly reduced the formation of film or spots on the articles cleaned or rinsed with such a composition.

The lipases, used according to the present invention, may be of any suitable origin such as yeasts, fungi and bacteria. Preferably, however, they are of bacterial origin, and particularly preferably they belong to the class of bacterial lipases which show a positive immunological cross-reaction with the antibody of the lipase, produced by the microorganism C 7097 (R) 2 Chromobacter viscosum var. lipolyticum NRRL B-3673.

This lipase has been described in Dutch Patent Specification 154,269 of Toyo Jozo, and the microorganism is available to the public at the United States Department of Agriculture, Agricultural Research Service, Northern Utilization and Development Division at Peoria, Illinois, under the number NRRL B-3673. This lipase will hereinafter be referred to as "Toyo Jozo" 4 10 lipase. The preferred lipases of the present invention should show a positive immunological cross-reaction with the Toyo Jozo lipase antibody, using the standard and well-known immunodiffusion procedure according to Ouchterlony (Acta. Med. Scan., 133, pages 76-79 (1950)).

a* The preparation of the antiserum is carried out as follows: 20 Equal volumes of 0.1 mg/ml antigen and of Freund's adjuvant (complete or incomplete) are mixed until an emulsion is obtained. Two female rabbits are injected o 9 8o' with 2 ml samples of the emulsion according to the following scheme: day 0 antigen in complete Freund's adjuvant day 4 antigen in complete Freund's adjuvant day 32 antigen in incomplLte Freund's adjuvant day 60 booster of antigen in incomplete Freund's adjuvant.

The serum containing the required antibody is prepared by centrifugation of clotted blood, taken on day 67.

The titre of the anti-Toyo Jozo-lipase antiserum is determined by the inspection of precipitation of serial dilutionsof antigen and antiserum according to the Ouchterlony procedure. A 25 dilution of antiserum was 71 i ft ts f C tt C C

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C C C CG CC C C cc CE C tC C CS C CC C CC C C CI

SC

C 7097 (R) 3 the dilution that still gave a visible precipitation with an antigen concentration of 0.1 mg/ml.

All lipases showing a positive immunological cross reaction with the Toyo Jozo lipase antibody as hereabove described are preferred lipases according to the present invention. Typical examples thereof are the lipases ex Pseudomonas fluorescens IAM 1057 (available under the trade name Amano-P), the lipase ex 10 Pseudomonas fragi FERM P 1339 (available under the trade name Amano-B), lipase ex Pseudomonas nitroreducens var. lipolyticum FER P 1338, the lipase ex Pseudomonas sp. available under the trade name Amano-CES, the lipase ex Pseudomonas cepacia, lipases 15 ex Chromobacter viscosum, e.g. Chromobacter viscosum var. lipolyticum NRRLB 3673, commercially available from Toyo Jozo Co., Tagata, Japan; and further Chromobacter viscosum lipases from US Biochemical Corp., U.S.A. and Diosynth Co., The Netherlands, and lipases ex Pseudomonas gladioli.

The lipases of the present invention are included in the detergent composition in such an amount that the final detergent composition has a lipolytic enzyme activity of from 100 to 0.005 LU/mg preferably 25 to 0.05 LU/mg of the composition.

A Lipase Unit (LU) is that amount of lipase which produces 1/umol of titratable fatty acid per minute in a pH stat. under the following conditions: temperature 30 0 C; pH 9.0; substrate is an emulsion of 3.3 wt.% of olive oil and 3.3% gum arabic, in the presence of 13 mmol/l Ca 2 and 20 mmol/l NaCi in mmol/l Tris-buffer.

Naturally, mixtures of the above lipases can be used.

The lipases can be used in their nonpurified form, or i i C 7097 (R) 4 in a purified form, e.g. purified with the aid of wellknown adsorption methods, such as a phenylsepharoseadsorption techniques.

The composition of the invention may furthermore comprise the usual ingredients of dishwashing or rinse compositions. Thus it may contain one or more alkali salts commonly used in dishwashing compositions. Thus, it may contain organic and/or inorganic builders such cc 10 as the alkali metal ortho-, pyro and tripolyphosphates and hexametaphosphates, silicates, carbonates, a c c zeolites, borates, citrates, carboxymethyloxyco c succinates, nitrilotriacetates and ethylenediaminetetraacetates, polymeric polyelectrolytes such as polyacrylates, polymaleates, and other known organic and inorganic builder compounds.

C I Usually, the amount of builders in the composition varies from 10-90% by weight, generally from 30-70% by 20 weight.

Ce C f The composition may also contain a detergent-active C* compound. If a detergent-active compound is included, it usually is in an amount of from 0.5-10%, usually 1- Any well-known type of detergent active compound may be used, such as soaps, synthetic anionic, nonionic, amphoteric detergent surfactant and mixtures thereof. Preferably, a nonionic detergent surfactant is used, especially a low-foaming one. Suitable examples of such nonionic detergent surfactants can easily be found in M.Schick "Nonionic Surfactants" (1967).

The composition may furthermore contain other useful additives such as bleaching agents, bleaching agent activators, hydrotropes, fillers, perfumes, colouring agents, germicides, soil-suspending agents, aminopolyphosphonic acids and alkali metal or alkaline earth

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C 7097 (R) metal salts thereof, clays such as hectorites, anticorrosion agents such as fatty acids, benztriazole and so on. Other enzymes such as proteases, amylases, oxidases may also be included.

As bleaching agents the peroxygen type bleaching agents, preferably with a bleach precursor such as TAED are suitable for inclusion in the machine dishwashing compositions.

B 0 C Sc A typical example of a conventional 'machine dishwashing 0 C L, composition usually contains an alkali metal tripolyphosphate in an amount of from 20-60%, an alkali metal 1V silicate in an amount of from 40-80%, or an alkali metal disilicate in an amount of 5-30% by weight a peroxy type bleaching agent in an amount of from 1-15%, a low-foaming detergent surfactant in an amount of from and minor ingredients such as perfumes, c colouring agents, hydrotropes, fillers, etc.

When formulated as a rinse composition, it may contain C, from 0.5-10% by weight of a nonionic surfactant, from 5-25% by weight of an inorganic or organic acid, from by weight of a hydrotrope, dyes, germicides, clays, silica sols, etc., the balance being water. The products of the invention can be formulated in any desirable form, such as powders, granulates, cakes, bars, pastes, liquids etc. The invention will further be illustrated by way of example.

Example 1 In a commercial dishwashing machine tests were carried i out under the following conditions: i Ln~ C 7097 (R) detergent composition dosage lipase dosage water hardness 30 g 2.5 g 15 LU/ml) main wash 270 GH flood 90 GH rinse 1 90 GH rinse 2 9" GH final rinse 90 GH 55*C 60 minutes clean dishes clean .glasses 35 g egg-yolk, added at the beginning of the main wash.

as ati Sa I Ib It L a It Irlg I:a II *I It *I I C I Et *a a C as wash temperature and time articles to be cleaned test soil 15 The detergent composition had the following formulation: in gr.

sodium tripolyphosphate 11.61 sodium carbonate 2.7 20 TAED 1.81 sodium perborate 2.43 calcium-Dequest 0.397 sodium disilicate 3.3 low foaming nonionic 0.405 (Plurafac hectorite clay (Laponite XLS) 0.675 sodium sulphate 5.610 amylase (4.8 Maltose units/mg) 0.540 As lipase, the Toyo Jozo lipase was used.

The test was carried out in two one with lipase.

runs, one without and The glasses were appraised by an expert panel as to their visual appearance, and were given a score according to the following scale: mfr- Ig io.- m" C 7097 (R) Film 1. no film 2. slight film 3. clear film 4. heavy film Spots 1. no spots 2. 1-5 spots 3. 5-10 spots 4. 11-20 spots more than 20 spots The following results were obtained: cc cC cC c o C

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C C, I

CL

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rr c o o CCt CriO C 00

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C C c CCC C CC CU U C CC

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C CC Cc C C CC 10 run 1 (no lipase) average film score 2.3 average number of spots 250 run 2 (with lipdses) 2.3 100 Example 2 The test of Example 1 was repeated, but under the following different conditions: wash temperature 20 soil standard soil; at the end of the main wash, clean plates were put in the machine, so that no cleaning took place in the final rinse, but only a carry-over took place.

no lipase added in the final rinse 2.5 g Toyo Jozo lipase was added to the final rinse (15 LU/ml).

run 1 run 2 The main wash composition had the following formulation: k i Kj C 7097 (R) 9. I 9 49 9 I 9 9 9t 4' N 9 9 9 99 C It

C

C

C C 9 It .4 £9 .94 99 4' 9 9 XC It t 9 CL r.

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by weight sodium tripolyphosphate 36 sodium carbonate 9 sodium disilicate TAED 3.8 sodium perborate tetrahydrate 82.8 potassium metaborate 0.35 sodium metaborate 0.85 calcium-Dequest 0.63 10 Amylase (4.8 MU/mg) 1.8 Esperase (a protease; 675 GU/mg) 1.8 low-foaming nonionic (Plurafac RA 40) 1.35 hectorite (Laponite XLS) 2.25 benzotriazole 0.1 sodium sulphate 14.0 water The following spot and film scores of the glasses were obtained: run 1 (no lipase) average film score average spot score run 2 (with lipases) .5 2.7 Example 3 Replacing the Toyo Jozo lipase by the Amano-P lipase or Lipase MY (ex 'Candida cylindracea) or Amano AP-6 lipase (ex Appergill!us niger) in Example 2 gave similar results.

Example 4 The following formulation is an example of a rinse aid composition to which lipases can be added: C 7097 (R) low-foaming nonionic (Plurafac RA 30) citric acid sodium xyJlene suiphonate dye butylated hydroxytoluene water by weight 18 0.003 0.1 q.s.

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Claims (4)

1. A process for machine dishwashing or rinsing, comprising treating dishes with an aqueous liquid having dissolved or dispersed therein an effective amount of an enzymatic dishwashing or rinsing composition comprising from 0.5-10% by weight of a detergent surfactant and from 0-90% by weight of a builder, characterised in that it further comprises from 0.005-100 LU/mg of a lipolytic enzyme. c c ccO S2. A process according to claim 1, characterised in ce that the lipase is a bacterial lipase which shows a a positive immunological cross-reaction with the antibody of Ct t t 0! the lipase, produced by Chromobacter viscosum var.

Slipolyticum NRRL B 3673. c 4t

3. A process according to claim 2, characterised in that the lipase is producible by the microorganism .,te selected from the group consisting of Pseudomonas fluorescens, Pseudomonas fragi, Pseudomonas nitroreducens var. lipolyticum, Pseudomonas cepacia, Pseudomonas Sgladioli and Chromobacter viscosum.

4. A machine dishwashing process according to any one of the claims 1 to 3, characterised in that there is used a composition containing from 20-60% by weight of an alkali metal silicate, from 1-15% by weight of a peroxy type bleaching agent and from 0.5-5% by weight of a low-foaming nonionic detergent. CA;-. \i _i I L. 11 A machine rinsing process according to any one of claims 1 to 3, characterised in that there is used a composition containing, in an aqueous medium, from 0.5-10% by weight of a nonionic surfactant, from 5-25% by weight of an organic or inorganic acid, and from 1-5% by weight of a hydrotrope. DATED THIS 14TH DAY OF FEBRUARY 1991 UNILEVER PLC By its Patent Attorneys: GRIFFITH HACK CO. Fellows Institute of Patent Attorneys of Australia. *J t C 0 0I 0 *S a r CO 00 C C t 0 Ct C Ck a C "a C S CC C t 4 *r' I i