How to prevent insects in Chinese herbal medicine warehouse?

1 General treatment before storage. Before storage, medicinal materials must be screened to remove dirt, sand and sundries. Some eggs and pupae can be screened out. Then according to the nature of the medicinal materials, drying, such as air drying, sun drying, oven drying and so on. To minimize the water content of medicinal materials, which is not conducive to the hatching and growth of pests [2]. If it is found that medicinal materials have been eaten by insects, all medicinal materials should be inspected, and those that have been eaten by insects should be picked out or destroyed to avoid further spread. Insect-eating of classified medicinal materials is closely related to the nature of medicinal materials. In prevention and control, we should first study the characteristics of medicinal materials, and adopt different storage conditions according to their properties, especially the centralized storage and treatment of insect-prone medicinal materials, which can effectively prevent or reduce pests. There are mainly the following kinds of medicinal materials susceptible to insect pests [2]. 2. 1 General medicinal materials containing fatty oil (such as almond and platycladi seed, etc.). ), starch or sugar (such as barley, etc.). ) and protein (such as Cordyceps sinensis, etc. ) are easy to eat, because these ingredients are the nutrients of pests; However, medicinal materials containing spicy ingredients (such as cloves), chemical crystals (such as borneol) and minerals (such as gypsum) are generally not moth-eaten. 2.2 Soft or sugary medicinal materials that are easy to absorb moisture are prone to insects under wet conditions. 2.3 due to the protective tissue layer on the surface, the complete medicinal materials are not easy to be eaten by insects; However, the broken medicinal materials and decoction pieces are more moth-eaten than the original medicinal materials and are not easy to preserve. 2.4 honey medicinal materials, due to the increase of sugar and vulnerable to insects. 3 plant ash (charcoal) storage method This method is based on the experience of folk grain storage [3,4]. Fumigating and drying the medicinal materials once according to their respective characteristics before the rainy season, putting them into the tank until they are about 10 cm away from the tank mouth, covering the medicinal materials with woven bag materials that do not leak ash, covering them with 5 cm thick plant ash or charcoal with residual temperature, then covering them with 1 layer plastic film, covering them with ash to the tank mouth, and sealing them with plastic film; Plant ash and medicinal materials can also be stored layer by layer at intervals. Plant ash and charcoal can not only absorb the moisture in medicinal materials (the moisture absorption can reach 10% ~ 12% of their own weight), but also have insecticidal effect without pollution. Plant ash generally only uses 1 time, while charcoal can be reused after sun exposure. This method can be applied to the storage of yam, chrysanthemum, peach kernel and other medicinal materials containing sugar, starch, resin, volatile oil and oil. 4 Lime jar storage method For medicinal materials that are not suitable for drying and drying, and are easy to be affected with damp and moth-eaten, such as centipede and sugar ginseng, put them in a lime jar and seal them (put a proper amount of quicklime at the bottom of the jar). Calcium lime has a strong water absorption capacity, so that there is almost no water in the tank, so that moths and eggs can not be produced and hatched [5, 6]. When lime absorbs water to a certain extent, it will collapse and rise, so it should be replaced in time. Lime is usually arranged in spring every year, 1 a is enough. 5 Multi-layer bag storage method "Multi-layer bag" [7] is divided into three layers, namely, the outer layer is made of sacks, the middle layer is made of thick and soft ordinary non-toxic plastic bags, and the inner layer is made of white cloth bags. Put the dried medicinal materials into the inner layer and fasten the pockets respectively. When using "multi-layer bags" to store medicinal materials, we must pay attention to: after the medicinal materials are stored and extracted, we must tighten the bag mouth, especially the plastic bag mouth, which is the key to prevent mildew and moth. 6 Conventional mixing method This method [8] is divided into stacking mixing and bagging mixing. The stacking and mixing method is to pour the medicinal materials into an open container such as a dustpan, or put them on a clean floor and mix them by kneading. This method is beneficial to check the appearance quality of medicinal materials, and has little damage to medicinal materials, but it is time-consuming to operate. The bagging and mixing method is to put medicinal materials into cloth bags or sacks, and the quantity of medicinal materials should be 1/2 ~ 2/3 of the bag capacity. The mouth of the bag should be tied tightly, and then alternately turned up and down, rubbing vertically and horizontally several times. This method is efficient, but if it is not operated properly, it is easy to crush the medicinal materials. When mixing vegetables, the interior of the medicinal materials can be ventilated by rubbing, knocking and turning, and the medicinal materials can be easily dried by combining with sunlight irradiation, and the eggs remaining in the medicinal materials can be effectively killed. Generally, medicinal materials that are susceptible to mildew and insects, such as Achyranthes bidentata and Ziziphus jujuba seeds, are mixed for 5 ~ 7 d, and flowers, leaves and whole grass can be mixed 1d 1 time, and roots, rhizomes and barks can be mixed 1 time. Modified atmosphere storage is a storage method that reduces O2 content and increases CO2 content under certain temperature and sealing conditions. When the O2 content dropped below 0.8%, some pests died after 48 hours [5]; When O2 content dropped below 8% and CO2 content increased above 45%, all pests died within 3 days. This method can be applied to medicinal materials with different textures and components [9]. Commonly used modified atmosphere packaging methods include vacuum packaging, CO2-filled minus O2 packaging, N2-filled minus O2 packaging, deoxidizer packaging and so on. It is suggested that the packaging and storage methods of this kind of Chinese herbal pieces should be developed vigorously. In addition, there are sand sealing method and sealing method [10], both of which use the principle of reducing O2. For a large number of medicinal materials, the cylinder-type modified atmosphere method can be used: CO2 gas is directly charged into the bottom of the medicine storage container through a leather tube (it is best to use an iron drum, which has good sealing performance and is not easy to be bitten by rats or punctured by hard objects), and the O2 is gradually expelled by using the characteristic that the density of CO2 is greater than O2. When the mouth of the container overflows with beer smell, it means that CO2 is full, then pull out the rubber tube and seal the container. Lu [1 1] This method is used for 10 a maintenance of medicinal materials, without moth, mildew, oil flooding and discoloration, and the cost is low. Heat treatment exposes the medicinal materials to the sun. In summer, the temperature of direct sunlight can reach about 50℃, which can kill pests, but it must be sunny and thoroughly exposed, otherwise it will raise the temperature, hatch eggs and promote pest activities. For medicinal materials that are not suitable for light, they can be heated at about 60℃ by oven or microwave oven or far-infrared dryer to kill adults, pupae, larvae and some eggs [2]. The above method can also reduce the water content of medicinal materials, which is not conducive to the growth of pests and the hatching of eggs, but it is necessary to prevent the medicinal materials from losing oil and going bad. Medicinal materials infected with pests can be treated with steam at about 80℃ 10 ~ 20 min, or soaked in boiling water for a while, and then dried in the sun (oven), which can achieve the purpose of killing insects. This method is also suitable for packaging equipment and warehouse utensils infected with pests [2], but leaves, flowers, whole grass and gum medicinal materials should not be used, and other medicinal materials should also be prevented from being used. Cold storage method uses low temperature (0 ~ 10℃) to store medicinal materials, which can effectively prevent moth-eaten medicinal materials and gum medicinal materials that are not suitable for sun drying and sun drying [12], and it has also been reported that moth-eaten medicinal materials can be prevented below 15℃ [13]. Moths can also be killed by freezing (below -5℃) [2]. However, when using this method, it must be noted that if there is too much water in the medicinal materials, the medicinal materials will be frozen, and colloids such as protein and its protoplasm will be irreversibly solidified. After thawing, it can't be restored to its original state, the color becomes darker and the quality becomes worse [14]. The water content is too small, the medicinal materials are dry and fragile, and some medicinal materials will rot if they are too dry, which will affect the medicinal properties. Therefore, it is necessary to properly control the water content according to the different properties of medicinal materials, that is, to determine the "complete water" value of a medicinal material stored at a low temperature below 0℃ [15]. Guo once reported that ginseng should not be frozen [16]. 10 sch-raufaegon, saarbrü cken university, saarland, germany. Starr and Gunter. A method of killing medicinal pests has been developed [17]. They think that it is difficult for animal organs to tolerate the rapid release of pressure. Different pests have different sensitivities, but their mortality is generally proportional to pressure and pressure time. Increasing pressure can shorten the pressure time appropriately. For example, when the pressure is 10 1MPa, it takes 3 hours to kill all the grain beetles. When the pressure is 20 1MPa, the action time is only 20 min. Generally, it is more advantageous to use higher pressure than to extend the pressurization time. The equipment consists of gas cylinder, autoclave and vacuum pump. In operation, the original medicinal materials are filled into the autoclave, and after vacuumizing with a vacuum pump, CO2 gas enters the autoclave from the gas cylinder until the required pressure (generally 50 1MPa) is reached, and after the required time (generally 10 ~ 20 min), CO2 is quickly discharged, which can effectively kill pests. The method does not affect medicinal properties and does not pollute the environment. 1 1 60 Co-γ ray irradiation to kill insects Kong Lingjie et al. [18] studied the method of curing animal medicinal materials by 60 Co-γ ray irradiation, and thought that fumigation methods such as chloropicrin and aluminum phosphide could kill live insects, but it was difficult to kill eggs, and pests would recur under suitable temperature and humidity conditions; However, medicinal materials irradiated by 60Co-γ rays can be stored for 1 1 month at the longest under normal conditions. Its principle is that gamma rays have strong penetrating power and can kill live insects and eggs existing in objects, thus achieving the goal of completely eradicating pests. Experiments show that the minimum effective dose of radiation is 3 kGy. Before irradiation, medicinal materials should be sealed with polyethylene plastic bags to prevent insects from infecting the outside world. Generally speaking, the greater the irradiation dose of 60Co-γ ray, the better the insecticidal effect, but people are most concerned about whether the pharmacological effects of irradiated medicinal materials will be affected. Yang Yujun et al [19] took Gentiana macrophylla as the experimental object, and the research proved that the pharmacological effects of different kinds of Chinese herbal medicines would not change if the radiation dose was properly selected, so the appropriate minimum radiation dose should be selected as much as possible, taking Gentiana macrophylla as an example, and its radiation dose should not exceed 5 kGy. 12 wine steaming storage method Take a proper amount of alcohol or liquor (above 50 degrees), put it in a cup, tie gauze on it (to prevent the medicinal materials from falling into the cup), put it in the bottom of the tank filled with medicinal materials, and then put the medicinal materials into the tank, or directly spray alcohol or liquor on the medicinal materials layer by layer (generally, the amount of alcohol is 20-30 ml per kilogram of medicinal materials), and seal it to make the alcohol evaporate slowly. This method is ideal for animals, oily lipids, sugars and other medicinal materials, non-toxic, harmless, low in cost, simple and convenient to operate, and can also enhance the efficacy of some drugs and correct the odor, which is very suitable for the short-term preservation of Chinese medicines in hospital pharmacies (especially primary pharmacies) [20,265,438+0]. However, due to the hygroscopicity of alcohol, the medicinal materials preserved by this method should be turned in time; In addition, special attention should be paid to fire and explosion prevention during operation. 13 chemical fumigation method traditionally uses sulfur, which is burned to produce SO2, which plays an insecticidal role, but it is rarely used now because SO2 will destroy some effective components. It has been reported that the structure of effective components of Codonopsis pilosula has changed obviously after sulfur steaming, but it can basically be restored after 2 1 d [22]. At present, the most commonly used methods of Chinese herbal medicine warehouse are chloropicrin and aluminum phosphide fumigation. These two methods are powerful in killing insects and penetrating, and can kill mice without damaging fiber tissue. If used alternately, it can also prevent pests from producing drug resistance and the effect is more satisfactory. However, it is necessary to prevent residual poison when using it, which can only kill live insects and has little effect on eggs. Under suitable temperature and humidity conditions, eggs will hatch quickly [23]. Wu [24] adopted the improved "synergistic method" (the ratio of aluminum phosphide: ammonium bicarbonate: vinegar: vinegar residue is1g: 20g:10g:10g/m3), which can reduce the dosage of aluminum phosphide, reduce the toxicity and make the operation simple. Liu [25] and others used "grain protection" to prevent insects, and the effect was good. "Grain protection" is a grain pest protection agent approved by the Ministry of Health. Its dosage is only 20 g per 100 kg of medicinal materials. The slow-release technology is adopted, which has long action time, no toxicity and harm to human body, no residue and no peculiar smell, and not only has insect control effect, but also has insect control effect and inhibits egg hatching. It is worth popularizing. Using DMF to prevent insects also has certain effect [26]. DMF, namely dimethyl fumarate, is a food additive developed abroad in 1980s. It has the characteristics of low toxicity, high efficiency and broad spectrum antibacterial, and has strong mildew resistance and good insect-proof effect on Chinese herbal medicines. The operation method is as follows: a certain dose of DMF is put into several non-woven bags and then divided into medicinal materials. Other chemical fumigants include carbon tetrachloride, chloroform, ethylene oxide, etc. Attention should be paid to fire prevention, gas prevention and environmental pollution prevention when using. 14 anti-storage method is one of the traditional preservation methods of Chinese medicinal materials, and it is recorded that "people participate in asarum, borneol and rush". This method mainly uses some medicinal materials with special odor and insect repellent effect. ┎ What is a tomb? Mace, Chili, Lai, Wu, Kang? BR> For example, Zanthoxylum bungeanum and asarum can prevent insects from being eaten by animals such as Zaocys. Litsea cubeba is mostly used in snake medicine; Peony bark can control the pests of Alisma orientalis and Dioscorea opposita; Or use traditional Chinese medicine insect repellent such as borneol and camphor. This method is simple, does not need to add special equipment, and has good insect repellent effect, which is especially suitable for the storage of a small amount of medicinal materials. If some insect-prone medicinal materials are baked first, the effect will be better [28, 29]. When using this method, we should pay attention to prevent antler, ginseng, clove and other medicinal materials from mixing with borneol and camphor. Glycyrrhiza uralensis Fisch and Astragalus membranaceus can't be mixed with Euphorbia Euphorbia and Kansui, otherwise it is easy to produce oil, taste bad and taste bad [30]. 15 kelp (seaweed) pest control method The commercially available kelp or seaweed is packed in 2-3 layers of gauze bags and placed flat in the center of the medicinal materials. Each kilogram of kelp or seaweed can be put into 20 ~ 50 kilograms of medicinal materials, which can reduce the water content of medicinal materials by 8% ~ 15%. Among the entomogenous medicinal materials, the rice weevil and rice chaff decreased by 55% ~ 75%[3 1] compared with those before adding kelp and seaweed. It has also been reported that after adding kelp (65438+ according to the amount of medicinal materials), the bag for storing kelp or seaweed can be taken out from time to time, placed in a ventilated and dry place 1.5 h, or dried for 30 ~ 40 min. However, the pest control effect of this method on fruits with high sugar content and oil content is not ideal [33]. The reason why kelp and seaweed have control effect on medicinal pests needs further study from the chemical composition. 16 compound preparation method made of traditional Chinese medicine-compound Zanthoxylum tincture (100 ml) made of Zanthoxylum bungeanum (40 g) and camphor (5 g) has a good killing effect on the larvae and eggs of moths, beetles, woolly fishes, bookworms and other pests [34]. In operation, after drying the medicinal materials, put them into a container, put 1 layer of medicinal materials, spray 1 times of compound Zanthoxylum bungeanum tincture, and seal after the surface of the medicinal materials is wet sprayed. All pests can be killed within 2 hours. Generally, 3 kg of compound Zanthoxylum tincture is used to kill insects and 0.5 kg to prevent insects per 100 kg of medicinal materials. This method combines the principles and advantages of traditional Chinese medicine against coexistence and alcohol pest control. Zanthoxylum bungeanum and camphor contain a lot of volatile oil, which is spicy, and all kinds of insects automatically avoid it after smelling it, which takes a long time to control insects. Using ethanol as solvent can achieve the effect of sterilization and insecticidal. Using this method to kill insects, the effective rate is over 96%, and there is no residual toxin and no pollution. Hao [35] and Chen [36] also reported that compound Stemona tincture, Stemona tincture and pyrethrum tincture have good insect repellent and insecticidal effects.