Liquid preparation containing crude-drug extract

The present invention relates to a liquid preparation containing crude drug extracts in an amount of 5 to 50 w/v % in terms of a dry extract weight based on the whole amount of the liquid preparation, characterized by containing saccharides in an amount of 5 to 40 w/v % based on the whole amount of the liquid preparation and adjusting a pH to 4.5 to 5.5.This liquid preparation is suppressed in generating precipitate and suspended content with the course of time even if the crude drug extracts are contained in a high concentration and which is stable over a long period of time.

FIELD OF INVENTION

The present invention relates to a liquid preparation containing crude drug extracts which is suppressed in generating a precipitate and a suspended contents with the course of time and which is stable over a long period of time.

BACKGROUND OF THE INVENTION

Crude drugs are used as an active ingredient for cold and stomach medicines, nourishing tonics and the like. Many oral liquid preparations containing crude drug extracts are sold for practical use. A dosage of these commercially available liquid preparations containing crude drug extracts are usually 25 to 100 mL. However, considering the compliance of the consumers, who are old persons, children and persons having a weaker physical strength due to diseases, a dosage of medicines should preferably be reduced as much as possible. In order to administer a minimum dose, and furthermore to be effective even in a reduced dosage, crude drug extracts have to be contained in the whole amount of a liquid preparation in a high concentration. In this case, as a concentration of the crude drug components increases, contact between the crude drug components increases to cause aggregation, resulting in the problem that a generating amount of precipitation and turbidity increase with the course of time.

pH of a liquid preparation containing crude drug extracts has to be set up as low as possible to maintain the taste and the preservation. On the other hand, it is known that precipitation and turbidity are generated with the course of time by reducing the pH, and it has resulted in bringing about the problems that an unpleasant feeling is given to the consumers and the product value is damaged and that an influence to the effectiveness is concerned about.

In these liquid preparations containing crude drug extracts, generally it is well known that surfactants used as a solubilizer suppress the generation of precipitation and turbidity with the course of time. In this method, however, there have been the problems that a large amount of surfactants is required and therefore an influence exerted to organisms by the surfactants is concerned about and that the surfactants are susceptible to hydrolysis at a lower pH and therefore the solubilizing effect is reduced.

A method for preventing precipitation and turbidity originating in a crude drug by adding a polyoxyethylene-hardened castor oil derivative and polyvinylpyrrolidone at pH 3.0 to 4.5 is reported in Japanese Patent Application Laid-Open No. 61-268267, and a liquid preparation containing crude drug extracts which is adjusted to have a pH of 2.2 to 3.8 by adding polyoxyethylene-polyoxypropylene glycol and which is stable over a long period of time is reported in Japanese Patent Application Laid-Open No. 2000-38345. However, these methods are not sufficient, and it is difficult to apply them to liquid preparations containing crude drug extracts in a high concentration.

Accordingly, an object of the present invention is to provide a stable liquid preparation containing crude drug extracts which is suppressed in generating precipitate and suspended contents with the course of time even if crude drug extracts are contained in a high concentration.

SUMMARY OF THE INVENTION

Investigations carried out by the present inventors in order to solve such problems as described above have resulted in finding that in a liquid preparation containing crude drug extracts in an amount of 5 to 50 w/v % in terms of a dry weight amount based on the whole amount of the liquid preparation, precipitation and turbidity generated with the course of time can be suppressed by adding saccharides in an amount of 5 to 40 w/v % based on the whole amount of the liquid preparation and adjusting the pH to 4.5 to 5.5, and thus they have completed the present invention.

That is, the present invention provides a liquid preparation containing crude drug extracts in an amount of 5 to 50 w/v % in terms of a dry weight amount based on the whole amount of the liquid preparation, characterized by containing saccharides in an amount of 5 to 40 w/v % based on the whole amount of the liquid preparation and adjusting the pH to 4.5 to 5.5.

Further, the present invention provides a liquid preparation containing crude drug extracts in an amount of 5 to 50 w/v % in terms of a dry weight amount based on the whole amount of the liquid preparation which is suppressed in generating a precipitate originating in the crude drug, characterized by containing saccharides in an amount of 5 to 40 w/v % based on the whole amount of the liquid preparation and adjusting the pH to 4.5 to 5.5.

DETAILED DESCRIPTION OF THE INVENTION

Further, included as well in the crude drug extract of the present invention are extracts obtained from organs such as livers, hearts or placentas of animals and hydrolyzed products produced by processing these extracts with acids, bases or enzymes.

Among such crude drug extracts, preferably included is one or more crude drug extracts selected from animal and vegetal extracts comprising epimedium grandiflorum morren, oriental bezoar, civet, Cuscutae semen, garlic, ginseng, panax notoginseng F. H. chen, and cornu cervi parvum and hydrolyzed products of animal organs. One or more of crude drug extracts containing at least a garlic extract is particularly preferred.

In a certain case, solvents such as alcohol used in a certain case in extracting may remain in these crude drug extracts.

In the case of a tincture and a fluid extract, an amount of the dry weight extracts means an amount of solid content residue by evaporation, i.e., it can be lead from the residual weight (evaporation residue) obtained from 10 ml of a tincture or a fluid extract in a beaker whose weight is known, drying it up on a boiling water bath by evaporation, drying at 105° C. for 6 hours and then cooling in a desiccator (containing silica gel). For example, an amount of a solid content in 1 mL of a tincture having 300 mg of an evaporation residue is 30 mg. In the case of a viscous extract, an amount of the dry weight in the crude drug extracts means a solid content amount converted from a drying loss obtained by a test method prescribed in Japanese Pharmacopoeia. For example, an amount of a solid content contained in 1 g of a viscous extract having a loss on drying of 60% is 400 mg.

The saccharides used in the present invention include sugar alcohol, monosaccharides, disaccharides, polysaccharides and mixtures thereof. Sugar alcohol, monosaccharides and disaccharides are preferred, and sugar alcohol is particularly preferred. A blending amount of these saccharides can be used in the range of 5 to 40 w/v % based on the whole amount of the oral liquid preparation, and it is preferably 10 to 40 w/v %, more preferably 20 to 30 w/v %.

The sugar alcohol includes erythritol, xylitol, maltitol, mannitol, D-sorbitol, lactitol, glycerol, inositol and mixtures thereof and preferably includes sorbitol or xylitol, even more preferably xylitol.

The monosaccharides include fructose, fucose, mannose, glucose, galactose and ribose, and fructose, glucose and galactose are particularly preferred.

The disaccharides include sucrose, maltose, lactose and invert sugar, and sucrose and maltose are particularly preferred.

Oligosaccharide is preferred as the polysaccharides.

The liquid preparation containing the crude drug extracts of the present invention can be obtained, for example, by dissolving one or more of the crude drug extracts in water, centrifuging, if necessary, to remove insoluble matters, adding saccharides to the resulting aqueous solution and stirring, then suitably adding a pH controller to adjust the pH to 4.5 to 5.5, adding water to the whole amount and then filtrating.

EXAMPLES

The liquid preparation of the present invention shall be explained below with reference to examples, but the present invention shall by no means be restricted by them.

In all examples and comparative examples shown below, the whole amount was set to 50 mL or 60 mL, and these solutions were filtered and then filled into test tubes. The test tubes were sealed with caps and used as test solutions.

A ginseng viscous extract 4.67 g in terms of a dry weight was sufficiently stirred in a suitable amount of purified water, and xylitol 5.0 g was added thereto and dissolved. Then, 10% hydrochloric acid was used to adjust the pH to 5.0, and the whole amount was set to 50 ml with purified water (Sample 1).

An epimedium grandiflorum morren viscous extract 3.38 g in terms of a dry weight was sufficiently stirred in a suitable amount of purified water, and xylitol 10.0 g was added thereto and dissolved. Then, sodium hydrogencarbonate was used to adjust the pH to 5.0, and the whole amount was set to 50 ml with purified water (Sample 2).

A Cuscuta chinensis Lam. viscous extract 3.40 g in terms of a dry weight was sufficiently stirred in a suitable amount of purified water, and xylitol 10.0 g was added thereto and dissolved. Then, 10% hydrochloric acid was used to adjust the pH to 4.5, and the whole amount was set to 50 ml with purified water (Sample 3).

A garlic viscous extract 14.1 g in terms of a dry wieght was sufficiently stirred in a suitable amount of purified water, and xylitol 15.0 g was added thereto and dissolved. Then, 10% hydrochloric acid was used to adjust the pH to 5.0, and the whole amount was set to 50 ml with purified water (Sample 4).

A liver-hydrolyzed product viscous extract 2.50 g in terms of a dry weight was sufficiently stirred in a suitable amount of purified water, and xylitol 15.0 g was added thereto and dissolved. Then, 10% hydrochloric acid was used to adjust the pH to 4.5, and the whole amount was set to 50 ml with purified water (Sample 5).

Oriental benzoar tincture 3.17 mg in terms of a dry substance, a civet tincture 4.10 mg in terms of a dry weight, a garlic viscous extract 14.1 g in terms of a dry weight and a ginseng viscous extract 4.67 g in terms of a dry weight were sufficiently stirred in a suitable amount of purified water, and xylitol 10.0 g was added thereto and dissolved. Then, 10% hydrochloric acid was used to adjust the pH to 5.0, and the whole amount was set to 50 ml with purified water (Sample 6).

A garlic viscous extract 14.1 g in terms of a dry weight and a liver-hydrolyzed product viscous extract 2.50 g in terms of a dry weight were sufficiently stirred in a suitable amount of purified water, and xylitol 10.0 g were added thereto and dissolved. Then, 10% hydrochloric acid was used to adjust the pH to 4.5, and the whole amount was set to 50 ml with purified water (Sample 7).

An epimedium grandiflorum morren viscous extract 84.5 mg in terms of a dry weight, a oriental benzoar tincture 11.9 mg in terms of a dry substance, a Cuscuta chinensis Lam. viscous extract 510 mg in terms of a dry weight, a garlic viscous extract 14.1 g in terms of a dry weight, a ginseng viscous extract 4.67 g in terms of a dry weight and Cornu cervi parvum fluid extract 16.7 mg in terms of a dry weight were sufficiently stirred in a suitable amount of purified water, and xylitol 10.0 g was added thereto and dissolved. Then, 10% hydrochloric acid was used to adjust the pH to 4.5, and the whole amount was set to 50 ml with purified water (Sample 8).

In the same manner as in Example 8, 10% hydrochloric acid was used to prepare a test solution of pH 4.0 (Sample 9).

In the same manner as in Example 8, 10% hydrochloric acid was used to prepare a test solution of pH 5.0 (Sample 10).

In the same manner as in Example 8, sodium hydrogencarbonate was used to prepare a test solution of pH 5.5 (Sample 11).

In the same manner as in Example 8, xylitol 5.0 g was added to the whole amount of 50 mL to prepare a test solution (Sample 12).

In the same manner as in Example 8, xylitol 15.0 g was added to the whole amount of 50 mL to prepare a test solution (Sample 13).

A ginseng viscous extract 4.67 g in terms of a dry weight was sufficiently stirred in a suitable amount of purified water. Then, 10% hydrochloric acid was used to adjust the pH to 5.0, and the whole amount was set to 50 ml with purified water (Sample 14).

An epimedium grandiflorum morren viscous extract 3.38 g in terms of a dry extract was sufficiently stirred in a suitable amount of purified water. Then, sodium hydrogencarbonate was used to adjust the pH to 5.0, and the whole amount was set to 50 ml with purified water (Sample 15).

A Cuscuta chinensis Lam. viscous extract 3.40 g in terms of a dry weight was sufficiently stirred in a suitable amount of purified water. Then, 10% hydrochloric acid was used to adjust the pH to 4.5, and the whole amount was set to 50 ml with purified water (Sample 16).

A garlic viscous extract 14.1 g in terms of a dry weight was sufficiently stirred in a suitable amount of purified water. Then, 10% hydrochloric acid was used to adjust the pH to 5.0, and the whole amount was set to 50 ml with purified water (Sample 17).

A liver-hydrolyzed product viscous extract 2.50 g in terms of a dry weight was sufficiently stirred in a suitable amount of purified water. Then, 10% hydrochloric acid was used to adjust the pH to 4.5, and the whole amount was set to 50 ml with purified water (Sample 18).

A oriental benzoar tincture 3.17 mg in terms of a dry weight, a civet tincture 4.10 mg in terms of a dry weight, a garlic viscous extract 14.1 g in terms of a dry extract and a ginseng viscous extract 4.67 g in terms of a dry weight were sufficiently stirred in a suitable amount of purified water. Then, 10% hydrochloric acid was used to adjust the pH to 5.0, and the whole amount was set to 50 ml with purified water (Sample 19).

A garlic viscous extract 14.1 g in terms of a dry weight and a liver-hydrolyzed product viscous extract 2.50 g in terms of a dry weight were sufficiently stirred in a suitable amount of purified water. Then, 10% hydrochloric acid was used to adjust the pH to 4.5, and the whole amount was set to 50 ml with purified water (Sample 20).

An epimedium grandiflorum morren viscous extract 84.5 mg in terms of a dry weight, a oriental benzoar tincture 11.9 mg in terms of a dry weight, a Cuscuta chinensis Lam. viscous extract 10 mg in terms of a dry weight, a garlic viscous extract 14.1 g in terms of a dry weight, a ginseng radix viscous extract 4.67 g in terms of a dry extract and a Cornu Cervi Parvum fluid extract 16.7 mg in terms of a dry weight were sufficiently stirred in a suitable amount of purified water. Then, 10% hydrochloric acid was used to adjust the pH to 4.5, and the whole amount was set to 50 ml with purified water (Sample 21).

A panax notoginseng F. H. chen viscous extract 17.2 g in terms of a dry weight was sufficiently stirred in a suitable amount of purified water, and xylitol 6.0 g was added thereto and dissolved. Then, the whole amount was set to 60 ml with purified water to obtain a solution having a pH of 4.9 (Sample 22).

A panax notoginseng viscous extract 17.2 g in terms of a dry weight was sufficiently stirred in a suitable amount of purified water, and fructose 6.0 g was added thereto and dissolved. Then, the whole amount was set to 60 ml with purified water to obtain a solution having a pH of 4.9 (Sample 23).

A panax notoginseng viscous extract 17.2 g in terms of a dry weight was sufficiently stirred in a suitable amount of purified water, and sucrose 6.0 g was added thereto and dissolved. Then, the whole amount was set to 60 ml with purified water to obtain a solution having a pH of 5.0 (Sample 24).

A panax notoginseng viscous extract 17.2 g in terms of a dry weight was sufficiently stirred in a suitable amount of purified water. Then, the whole amount was set to 60 ml with purified water to obtain a solution having a pH of 4.8 (Sample 25).

Test Example 1

Sample 1 and Sample 14 were used to carry out a storage test at 60° C. for 2 weeks. Further, Samples 2 to 8 and Samples 15 to 21 were used to carry out a storage test at 40° C. for 2 weeks. In these cases, the suppressing effect against a precipitate or a suspended matter of the crude drugs with the course of time by adding sugar alcohol was observed. The results thereof are shown in Table 1. As a result thereof, a precipitate or a suspended matter was scarcely observed in storage for 2 weeks in Samples 1 to 8 in which sugar alcohol was added, but in Samples 14 to 21 in which sugar alcohol was not added, a precipitate or a suspended matter was observed with the course of time.

Test Example 2

Samples 8 to 11 were used to carry out the storage test at 40° C. for 2 weeks. In these cases, an influence exerted on a precipitate or a suspended matter of the crude drugs generated with the course of time due to a change in the pH was observed. The results thereof are shown in Table 2. As a result thereof, precipitate or suspended content was scarcely observed in a range of 4.5 to 5.5, but in the case of a pH 4.0, a precipitate or a suspended matter was observed to be generated with the course of time.

Test Example 3

Samples 8, 12, 13 and 21 were used to carry out the storage test at 40° C. for 2 weeks. In these cases, an influence exerted on a precipitate or a suspended matter of the crude drugs generated with the course of time by an adding amount of sugar alcohol was observed. The results thereof are shown in Table 3. As a result thereof, a precipitate or a suspended matter was scarcely observed in Samples 8, 12 and 13.

Test Example 4

Samples 22 to 25 were used to carry out the storage test at 40° C. for 2 months. In these cases, an influence exerted on a precipitate or a suspended matter of the crude drugs generated with the course of time by adding saccharides was observed. The results thereof are shown in Table 4. As a result thereof, a precipitate or a suspended matter was scarcely observed in Samples 21, 22, 23 and 24, but in Sample 25 in which saccharides were not added, a precipitate was observed with the course of time.

Industrial Applicability

According to the present invention, the liquid preparation containing crude drug extracts which is suppressed in generating the precipitate and the suspended content with the course of time can be provided even if crude drug extracts are contained in a high concentration and which is stable over a long period of time.