PRESERVATIVE COMPOSITION AND USE THEREOF

Abstract: A process for improving the durability of cut plant parts, especially cut flowers, in which the cut surface of the plant part is brought into contact with an aqueous solution, which optionally comprises additives of organic or inorganic acid, preservatives, nutrients and similar additives which conventionally are used in such fresh keeping agents. The process is characterized in that said aqueous solution, furthermore, comprises dissolved a ''quinine group constituent'' comprising at least one of quinine and to quinine closely related substances, especially quinidine, cinchonine and cinchonidine, as well as derivatives, especially salts, of any such substance, in a plant physiologically active quantity.

Description: PRESERVATIVE COMPOSITION AND USE THEREOF. This invention is related to a process for improving the durability of plants, especially cut plant parts, particularly cut flowers. In this process e.g. the cut surface of the plant part is brought into contact with an aqueous solution which optionally comprises additives of organic acid, preserv¬ atives, nutrients and similar additives which are conven¬ tionally used in such fresh keeping agents. The invention is characterized in that the aqueous solution also comprises dissolved a "quinine group constituent" which expression comprises quinine, quinine derivatives (quinine salts) and also substances closely related to quinine, especially quinidine, cinchonine, cinchonidine, and derivatives (salts) thereof, in an at least active quantity, especially a plant physiological or microbe physiological quantity, which improves the durability of the cut plant parts. Said plant parts consist especially of cut flowers, e.g. carnations, roses, freesia, tulips, daffodils, chrysanthemum, snap¬ dragons, asters, lilies, mimosa, orchids, narcissus, etc., but may also consist of other cut plant parts, e.g. cuttings. The quantity of "quinine group constituent", i.e. quinine, quinidine, cinchonine, cinchonidine, quinine derivatives, etc., amounts to, based on dry weight, preferably at least 0.0001% by weight, e.g. at least 0.001 or 0.01% by weight, optionally at least 0.1% by weight, and preferably to at most 10% by v.'eight, at most 5% by weight, at most 2% by weight or at most 1% by weight, optionally at most 0.1% by weight or at most 0.01% by weight. Corresponding contents of "quinine group constituent", e.g. quinine and quinine derivatives, in the solution ready-for-use are suitably, based on the weight, at least 0.00001%, e.g. at least 0.0001% or 0.001% and frequently preferably at most 0.1%, at most 0.05%, at most 0.025% or at most 0.01%. As suitable such derivatives (salts, anions) there may be mentioned acetate, acetyl salicylate, ascorbate, benzoate, bicarbonate, bisulphate, carbonate, citrate, (mono or dihydro) halide, e.g. dihydrobromide, dihydroiodide, hydroiodide, dihydrochloride, hydrochloride, nitrate, phosphate, sulphate, etc., preferably of quinine but also of quinidine, cinchonine or cinchonidine. It is also preferable that the agent comprises an organic acid which can be used for achieving a desired pH value and also act as a component of a gas releasing agent for releasing carbon dioxide. Examples of such acids are citric acid, tartaric acid, formic acid, acetic acid, propionic acid, oxalic acid as well as other saturated and unsaturated mono, di or polyvalent carboxylic acids with 2, 3, 4, 5, 6 or more carbon atoms and optionally comprising further substituents which are water-soluble. It is preferable that pH of the solution ready-for-use is at most 6, e.g. at most 5, at most 4, at most 3.5 or at most 3, and usually at least 1, at least 1.5 or at least 2. The content of organic acid, based on non-aqueous or dry weight, may be at least 0.01%, preferably at least 0.1%, at least 1% or at least 10%, and preferably at most 99%, at most 25% or at most 10%. Furthermore, it is suitable that a preservative is included in the agent. Examples of such preservatives are such based on benzoic acid and derivatives thereof, e.g. sodium or potassium benzoate, as well as a large number of other per se well-known preservatives, e.g. quarternary ammonium compounds or chlorine containing compounds, such as chloramine. Furthermore, some organic acids may also be used as preservatives, e.g. sorbic acid. The content of preservatives in the agent, based on water-free weight, is preferably at least 0.01%, especially at least 0.1%, at least 1% or at least 10%, and preferably at most 9 . 9%, especially at most 50% or at most 10%. In the process according to the invention as well as in the agent according to the invention preferably also organic nutrients are used, especially sugars, preferably mono- saccharides or disaccharides, such as dextrose, fructose, lactose, maltose, saccharose, etc. The quantity of nutrients in the agent is, based on the weight of water-free agent, at least 0.01%, e.g. at least 0.1% or at least 1%, and optionally at least 10% or at least 50%, and preferably at most 99.9%, especially at most 90% or at most 50% or at most 25%. The agent may also comprise an effervescent agent, i.e. in contact with water gas releasing agent, especially an agent which evolves carbon dioxide, such as a combination of bicarbonate and acid, especially organic acid, and preferably sodium, potassium or ammonium bicarbonate. Such agents are added in a quantity which is required for improving the dis¬ solution of the concentrate, said concentrate mixed with said agents preferably being compacted to tablets of a suitable dose size. The agent or concentrate may also comprise other components, such as inorganic nutrients of the type potassium, nitrogen and phosphor containing agents, wetting agents, e.g. anionic, nonionic, cationic or zwitterionic wetting agents, fillers, e.g. soluble sulphates, colouring agents, etc. Said sub¬ stances are not included in the stated contents and quantity ratios. The quantity of concentrate which can be used in an aqueous solution varies but it is preferable that at least 0.1 g, at least 1 g, at least 2.5 g or at least 5 g per litre of aqueous solution, and optionally at most 100 g, at most 50 g, at most 25 g, at most 10 g, at most 5 g or at most 2 g per litre of aqueous solution are added. Suitable contents in the aqueous solution of the various constituents may be from one part per ten thousands, especially from one per thousand or from one per five hundreds, especially from one per hundred, and up to one tenth, preferably one per fifty, of the stated contents in the water-free agent of the various constituents, e.g. one per five thousands to one fiftieth and especially about one per hundred to one per thousand or one per fifty to one per five hundreds. The invention is disclosed more thoroughly below with specific examples. Durability tests in these were performed at ambient temperatures varying between 15 and 35°C. EXAMPLE 1 A number of agents comprising, based on the weight, 4.9% citric acid, 4.1% sodium benzoate, 0.5% "quinine group constituent" consisting of quinine hydrochloride and 90.5% saccharose were prepared. A quantity of said agent was used directly in a quantity of 0.1 g, l g, 5 g and 10 g resp. per litre of water. A second quantity of said agent was mixed with a gas releasing agent consisting of citric acid and sodium bicarbonate in a stoichiometric ratio and in a total quantity of 0.25 g per g of said agent and was pressed to tablets with a weight of about 1 g. These tablets which evolve carbon dioxide in water were used for preparing aqueous solutions of the same strength as those mentioned above. The test solutions prepared in this way were tested for keeping cut flowers consisting of carnations, roses, freesia, tulips, daffodils and chrysanthemum. In each case a substan¬ tial increase of the period of time for which the flowers were maintained fresh was obtained, usually to a fresh keeping period of at least 3 weeks, and in average an increase of between 100 and 400% of the period of time they were kept fresh without said agent. EXAMPLE 2 Further tests were performed with the basic composition stated in claim 1 but with varying contents of "quinine group constituent" consisting of quinine hydrochloride, quinine sulphate, quinidine hydrochloride and cinchonidine hydro¬ chloride in said agent. The compounds mentioned above were tested in quantities, based on water-free weight, of 0.001%, 0.01%, 0.1%, 1% and 10%, whereby an essential improvement of the fresh keeping was obtained which was especially noticable at contents of 0.1% and above. EXAMPLE 3 Further experiments with somewhat deviating basic compositions were performed. The agent was pressed to tablets of the composition stated in Table 1. Each tablet was tested with good result in the water quantities 250 ml and 1000 ml. Especially good results were obtained with the compositions according to Runs 5 and 6. The solutions of the tablets in water were tested on various types of cut flowers, such as roses, tulips, carnations, freesia, asters, daffodils and narcissus. An improvement of the durability to about 3-5 times the durability without the additive was obtained. TABLE 1 Composition of tablets for keeping flowers fresh Run 1 Run 2 Run 3 Run 4 Run 5 Run 6 Saccharose "Tabfine S 100 I" 1530 g 1530 mg 1530 mg 1530 g 1530 mg 1524 mg Quinine hydrochloride 40 mg 40 mg 40 mg 20 mg 10 mg 6 mg Sodium benzoate 80 mg 80 mg 80 mg 80 mg 80 mg - Citric acid, water-free 230 mg 1000 mg 1500 mg 1000 g 1000 mg 600 mg Magnesium stearate 20 mg 30 mg 30 mg 30 mg 30 mg 20 mg 1900 mg 2680 mg 3180 mg 2660 mg 2650 mg 2150 mg PH 3.31 2 .52 2 .37 2 .51 2 .49 2.6-3.0 Note: The quantities are adapted to 250 ml of water EXAMPLE 4 Tests were performed under the conditions stated in Example 3, Runs 1 to 6, wherein the quinine hydrochloride was substituted with quinidine hydrochloride and with cinchonidine hydro¬ chloride resp. in the same quantities, i.e. 40, 20, 10 and 6 mg per dosis. The tests were performed with the same kind of flowers as in Example 3 and similar improvements of the durability were obtained. EXAMPLE 5 Tests according to Examples 1-4 were repeated in a series of runs in which fructose and dextrose were used as substitutes for saccharose, and, furthermore, entirely without any sugar, and with the use of tartaric acid, ascorbic acid and phosphoric acid instead of citric acid and with pH values adjusted to within the range 2-4. Furthermore, the use as preservatives of quarternary ammonium salts as substitutes for sodium benzoate was tested as well as exclusion of a particu¬ lar preservative, especially at low temperatures. In each of said tests an improvement of the durability was obtained which was especially obvious at contents of "quinine group constituent" in the aqueous solution above about 0.01% and especially above about 0.1%. Agents according to this invention are preferably used as aqueous solution and dry concentrate resp. therefor but may, of course, also be administrated in other ways, e.g. be applied on the stems of the plants, e.g. as a concentrate or in a suitable carrier. Furthermore, the constituents may be added separately or in arbitrary mixture. Cinchonidine and cinchonine and water-soluble compounds and derivatives thereof with an anion which do not inhibit the effect according to the invention, e.g. acetate, acetyl salicylate, ascorbate, benzoate, bicarbonate, bisulphate, carbonate, citrate, dihydrochloride, hydrochloride, nitrate, phosphate and sulphate are generally suitable as substitutes for or together with water-soluble quinine and quinidine compounds and derivatives. The invention does not comprise the use alone of quinoline salts, e.g. 8-oxyquinoline sulphate, or such compounds in contents between 50 and 250 mg per litre, especially not in combination with hydroxylamine hydrochloride, especially in contents of 50-250 mg/1, and/or benzimidazole, especially in contents of 10-50 mg/1. It may in certain cases be suitable to avoid the presence of compounds of the formula wherein R, is an alkyl group with 1-4 carbon atoms or an alkenyl group with 3-4 carbon atoms and M is ammonium or alkali metal ion, in an efficient quantity.

Claims: CLAIMS 1. . A process for improving the durability of cut plant parts, especially cut flowers, wherein the cut surface of the plant part is brought into contact with an aqueous solution, which optionally comprises additives of organic or inorganic acid, preservatives, nutrients and similar additives which are conventionally used in such fresh keeping agents, characterized in that the aqueous solution also comprises dissolved a "quinine group constituent" comprising at least one of quinine and to quinine closely related compounds, especially quinidine, cinchonine and cinchonidine, as well as derivatives, especially salts, of any such substance, in a plant physiologically active quantity. 2. A process according to claim 1, characterized in that the aqueous solution comprises one or more of the following characteristics: a) a content of 0.001-5% by weight of organic or inorganic acid, b) a content of 0.0001-5% by weight of preservatives, c) a content of 0.01-10% by weight of nutrients, especially sugars, d) a hydrogen ion concentration corresponding to a pH of at most 6, and e) a quinine group constituent in a quantity of at least 0.0001 and preferably at most 1% by weight. 3. A process according to claim 1 or 2, characterized in that the aqueous solution comprises one or more of the following characteristics: a) a content of at least 0.01 and preferably at most 1% by weight of organic or inorganic acid, b) a content of at least 0.001 and preferably at most 1% by weight of preservatives, c) a content of at least 0.01 and preferably at most 2% by weight of nutrients, d) a content of at least 0.001 and preferably at most 0.1% by weight of quinine group constituent, or e) a pH value of at most 5 and preferably at most 4 and especially at least 1. 4. An agent for keeping cut plant parts fresh, especially cut flowers, consisting of a dry, liquid containing or dissolved concentrate intended for diluting with water to a solution, which when contacted with cut surfaces of said plant parts improves their durability, which agent comprises at least one of the following substances: a) organic or inorganic acid b) preservatives c) nutrients characterized in that said agent, furthermore, comprises a "quinine group constituent" which when diluted with water gives a physiologically or for improving the durability of cut flowers and similar active dissolved content of quinine or to quinine closely related compounds, especially quinidine, cinchonine and cinchonidine and derivatives thereof, especially water-soluble salts, of one or more such substances, especially in a content of 0.001 to 90% by weight, based on water-free weight. 5. An agent according to claim 4, characterized in that it exhibits, in addition to the quinine group constituent, at least one of the following constituents in the stated per cent by weight quantities, based on water-free agent: a) 0.01-99% organic or inorganic acid b) 0.01-99% preservatives c) 0.01-99.9% nutrients. 6. An agent according to claim 4 or 5, characterized by exhibiting the following contents, in per cent by weight, of the defined constituents: a) at least 0.1 and preferably at most 50% organic or inorganic acid, b) at least 0.1 and preferably at most 50% preservatives, and c) at least 0.1 and preferably at most 90% nutrients, the content of quinine group constituent preferably being at least 0.1 and suitably at most 10. 7. An agent according to any of claims 4-6, characterized by also comprising substances which evolve gases when contacted with water, preferably carbon dioxide evolving substances, such as bicarbonate and a corresponding quantity of acid, especially sodium, potassium or ammonium bicarbonate, said agent preferably being present in the shape of an effervescent tablet. 8. An agent according to any of claims 4-7, characterized by comprising, based on water-free weight, 1-10, preferably about 5% carboxylic acid, especially citric acid, 0.01-10, preferably about 5% quinine group constituent, 70-99.5% mono or disaccharides, and optionally carbon dioxide evolving effervescent agent comprising bicarbonate and an organic acid, and optionally 1-10, preferably about 5% water-soluble preservatives, especially quarternary ammonium salt or benzoic acid derivatives. 9. An agent according to any of the preceding claims, characterized by comprising a buffer which is active in water for maintaining a pH within the range 1-6, preferably 2-4. 10. The use of the, agent according to any of claims 4-9 as a fresh keeping agent for preparing aqueous solutions for keeping cut plant parts, especially cut flowers, fresh. 11. The use in a physiologically active quantity of quinine group constituents comprising quinine and to quinine closely related substances, especially quinidine, cinchonine, cinchonidine, or derivatives, especially salts thereof, in an aqueous solution or a concentrate for an aqueous solution, for keeping cut flowers fresh.

Inventors: NORSTROEM ERIK, NORSTROEM, ERIK
Applicants: NORSTROEM ERIK, NORSTROEM, ERIK
Application year: 1989
Main classification: A01N3
IPC codes: A01N3