Application of monoterpene indole alkaloids in the preparation of antifungal drugs

Abstract

The present invention relates to the technical field of antifungal treatment, specifically to the application of monoterpene indole alkaloids in the preparation of antifungal drugs. The results show that the monoterpene indole alkaloids provided by the present invention have significant antibacterial activity against fungi, providing a new idea for the preparation of antifungal drugs.

Description

Technical Field

[0001] The present invention relates to the technical field of antifungal treatment, and particularly to the application of monoterpene indole alkaloids in the preparation of antifungal drugs. Background Art

[0002] Monoterpene indole alkaloids have a wide range of biological activities and can be used to treat various diseases. On the other hand, due to their complex structures, although it is difficult to produce them in large quantities by chemical synthesis, they can be directly extracted from plants existing in nature, which gives monoterpene indole alkaloids the advantages of natural drugs.

[0003] There have been many cases of applying monoterpene indole alkaloids in the pharmaceutical field reported. For example, the patent with the publication number CN113480538A discloses the application of a monoterpene indole alkaloid derivative in the preparation of drugs for preventing or treating cerebral ischemia-reperfusion injury. Another example is that the patent with the publication number CN115433185A discloses a monoterpene indole alkaloid, its preparation method and application, and the application fields include anti-Mycobacterium smegmatis, anti-Mycobacterium tuberculosis and the treatment of pulmonary tuberculosis.

[0004] However, in the current research on monoterpene indole alkaloids, most of them are applied to the treatment of bacterial pathogens such as anti-Mycobacterium smegmatis and anti-Mycobacterium tuberculosis. There is no report on the antifungal activity of monoterpene indole alkaloids for preventing and treating fungal infections, and this limitation restricts the application of monoterpene indole alkaloids in a wider field. Summary of the Invention

[0005] To overcome the above-mentioned disadvantages of the prior art, the purpose of the present invention is to provide the application of monoterpene indole alkaloids in the preparation of antifungal drugs.

[0006] To achieve the above-mentioned invention purpose, the present invention adopts the following technical solutions:

[0007] The application of monoterpene indole alkaloids in the preparation of antifungal drugs, and the structural formula of the monoterpene indole alkaloids is shown as formula (A) or formula (B):

[0008] (A) (B).

[0009] Preferably, the antifungal drugs include one or more of drugs that inhibit the growth of fungi, drugs that kill fungi, and drugs for treating diseases caused by fungal infections.

[0010] Preferably, the fungi include one or more of Ascomycota, Basidiomycota, Deuteromycota, and Zygomycota.

[0011] Preferably, the fungus includes one or more of Aspergillus niger, Sclerotinia sclerotiorum, and Fusarium oxysporum.

[0012] Preferably, the antifungal drug includes monoterpene indole alkaloids and pharmaceutically acceptable salts thereof.

[0013] Preferably, the antifungal drug includes monoterpene indole alkaloids and a pharmaceutically acceptable carrier or excipient.

[0014] Preferably, the pharmaceutically acceptable carrier or excipient includes one or more of a diluent, a binder, a lubricant, a solvent, a stabilizer, and a filler.

[0015] Preferably, the solvent includes one or more of dimethyl sulfoxide, N,N-dimethylformamide, ethanol, propylene glycol, acetone, and ethyl acetate.

[0016] Preferably, the concentration of the monoterpene indole alkaloids in the antifungal drug is 5 - 100 μg / mL.

[0017] The beneficial effects of the present invention are as follows:

[0018] Since fungi are eukaryotes and there are significant differences in biology and pharmacology between them and the bacterial pathogens in the fields where monoterpene indole alkaloids are commonly applied, the inventors unexpectedly found through research that the monoterpene indole alkaloids provided by the present invention have significant antifungal activity, showing inhibitory effects on various fungi, and can provide new ideas for the progress of preparing antifungal drugs. Moreover, the monoterpene indole alkaloids can be extracted from natural plants and have the safety advantages of natural drugs. Description of the Drawings

[0019] Figure 1 It is a schematic diagram of the comparison of the inhibition zones of Preparation Example 1, Preparation Example 2, and ketoconazole after culturing on PDA agar at 28°C for 3 days. Among them, Figure A is the schematic diagram of the inhibition zone of Preparation Example 1, Figure B is the schematic diagram of the inhibition zone of Preparation Example 2, and Figure C is the schematic diagram of the inhibition zone of ketoconazole;

[0020] Figure 2 It is a schematic diagram of the mycelial growth of Aspergillus niger cultured on PDA agar at 28°C with different concentrations of Preparation Example 1, Preparation Example 2, and ketoconazole;

[0021] Figure 3 It is a schematic diagram of the mycelial growth of Sclerotinia sclerotiorum cultured on PDA agar at 28°C with different concentrations of Preparation Example 1, Preparation Example 2, and ketoconazole;

[0022] Figure 4 It is a schematic diagram of the mycelial growth of Fusarium oxysporum cultured on PDA agar at 28°C with different concentrations of Preparation Example 1, Preparation Example 2, and ketoconazole. Detailed Embodiments

[0023] The present invention will be further described below in conjunction with the accompanying drawings of the specification and specific embodiments. Those of ordinary skill in the art will be able to implement the present invention based on these descriptions. In addition, the embodiments of the present invention described below are generally only a part of the embodiments of the present invention, rather than all of the embodiments. Therefore, all other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the scope of protection of the present invention.

[0024] Preparation Example 1

[0025] Using 10 kg of Bousigonia angustifolia, a plant of the genus Bousigonia in the Apocynaceae family, as the raw material, it was extracted with methanol at room temperature 3 times, 20 L each time. The methanol extracts were combined, and methanol was recovered under reduced pressure at a low temperature (40 °C) to obtain an extract. The extract was dissolved in an appropriate amount of 0.5% hydrochloric acid aqueous solution and extracted three times with an equal volume of ethyl acetate. The remaining acidic aqueous solution was adjusted to pH 7 - 8 with 10% ammonia water, and then extracted three times with an equal volume of ethyl acetate again. The ethyl acetate extracts this time were combined, and ethyl acetate was recovered under reduced pressure at a low temperature (40 °C) to obtain 90 g of an extract. The extract was first separated on a silica gel column and eluted with a gradient of dichloromethane - methanol (1:0 - 0:1), and a total of 10 elution fractions (Fr1 - Fr10) were obtained. Elution fraction 1 (Fr1), 8.4 g, was separated by medium-pressure reverse-phase C18 column chromatography and eluted with a gradient of methanol - water (10:90 - 100:0) to obtain 18 elution fractions (Sub1 - Sub18). Sub12 was purified by reverse-phase C18 preparative liquid chromatography and eluted with a gradient of acetonitrile - water (30:70 - 45:55, v / v) to obtain the compound rhazinilam (21 mg). The structural formula of rhazinilam is shown as follows:

[0026] 。

[0027] Preparation Example 2

[0028] It is basically the same as Preparation Example 1, and the difference is only that: Sub13 was purified by reverse-phase C18 preparative liquid chromatography and eluted with a gradient of acetonitrile - water (40:60 - 55:45, v / v) to obtain the compound rhazinal (10 mg). The structural formula of rhazinal is shown as follows:

[0029] 。

[0030] Example 1 Identification of the Bacteriostatic Effect of Monoterpene Indole Alkaloids

[0031] Place the sterilized filter paper (6 mm) on the surface of the PDA agar plate coated with Aspergillus niger, and add 10 μL of the compound solution (10 mg / mL) dissolved in DMSO to the filter paper. Use ketoconazole (10 mg / mL) as the positive control, and incubate at 28 °C for 3 days, with each sample repeated three times. The results are as Figure 1 shown. The diameter of the inhibition zone of Preparation Example 1 is 20.03 mm, the diameter of the inhibition zone of Preparation Example 2 is 29.41 mm, and the diameter of the inhibition zone of ketoconazole is 15.32 mm. Thus, both Preparation Example 1 and Preparation Example 2 have strong in vitro antifungal activities, and both are superior to the traditional antifungal agent ketoconazole.

[0032] Example 2 Comparison of mycelial growth inhibition rates of monoterpene indole alkaloids

[0033] Dissolve Preparation Example 1 and Preparation Example 2 in DMSO respectively, mix with the sterilized PDA medium at 50 °C and then pour into petri dishes to obtain media containing sample concentrations of 80, 40, 20, 10, 5, 2.5 μg / mL respectively. Then, place 5 μL of three test bacterial solutions with a concentration of 1 × 10 5 CFU / mL (Aspergillus niger, Sclerotinia sclerotiorum, and Fusarium oxysporum. Among them, Aspergillus niger is a fungus that can cause human diseases, Sclerotinia sclerotiorum and Fusarium oxysporum are common plant pathogenic fungi, and Fusarium oxysporum may also affect human health under specific conditions.) (Aspergillus niger (Aspergillus niger, preservation number CGMCC 3.17612), Sclerotinia sclerotiorum (Sclerotinia sclerotiorum, preservation number CGMCC 3.18027), and Fusarium oxysporum (Fusarium oxysporum, preservation number CGMCC 3.2830) are all obtained from the China General Microbiological Culture Collection Center) at 28 °C and culture on potato dextrose agar (PDA) medium, with each sample repeated three times. DMSO and ketoconazole are used as negative and positive controls respectively, and the results are as Figures 2 to 4 shown.

[0034] When the mycelium grows to the edge of the petri dish, calculate using the formula:

[0035] Inhibition rate (%) = 100 * (C - T) / C

[0036] where C is the average growth diameter of the mycelium in the negative control group, and T is the average growth diameter of the mycelium in the sample group. The comparison results of the inhibition rates are shown in Table 1. Preparation Example 1 and Preparation Example 2 have antifungal effects on Aspergillus niger, Sclerotinia sclerotiorum, and Fusarium oxysporum to varying degrees.

[0037] Table 1 Inhibitory effects of Preparation Example 1, Preparation Example 2, and ketoconazole on three fungi

[0038] 。

Claims

1. The use of monoterpene indole alkaloids in the preparation of antifungal drugs, characterized in that: The structural formula of the monoterpene indole alkaloid is shown in formula (A) or formula (B): The fungi include one or more of Aspergillus niger, Sclerotinia sclerotiorum and Fusarium oxysporum. The concentration of the monoterpene indole alkaloids in the antifungal drug is 5-100 μg / mL.

2. The use according to claim 1, characterized in that: The antifungal drugs are drugs used to treat fungal infections in animals and plants.

3. The use according to claim 1, characterized in that: The antifungal drug refers to a drug used to treat fungal infections in humans.

4. The use according to claim 1, characterized in that: The antifungal drugs include monoterpene indole alkaloids and pharmaceutically acceptable salts thereof.

5. The use according to claim 1, characterized in that: The antifungal drug comprises monoterpene indole alkaloids and a pharmaceutically acceptable carrier or auxiliary material.

6. The use according to claim 5, characterized in that: The pharmaceutically acceptable carrier or excipient includes one or more of a diluent, a binder, a lubricant, a solvent, and a stabilizer.

7. The use according to claim 6, characterized in that: The solvent includes one or more of dimethyl sulfoxide, N,N-dimethylformamide, ethanol, propylene glycol, acetone, and ethyl acetate.

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