Method for degrading residual antibiotics in macrolide antibiotic fermentation waste

Abstract

The invention discloses a method for degrading residual antibiotics in macrolide antibiotic fermentation waste. The method comprises the following steps: taking antibiotic mushroom dregs as a degradation raw material, stainless steel beads as a grinding medium, and taking an oxidizing agent and a pro-oxidizing agent as ball milling aids. The mixture is subjected to a grinding reaction in a ball milling tank, treatment of the mushroom dregs is completed, the content of antibiotics in the mushroom dregs obtained after ball milling is reduced to 99% or below, the antibiotic resistance of the antibiotics disappears, and the mushroom dregs can be further used for re-fermentation of erythromycin. The method has the advantages that the process route is short, the reagent dosage is small, the price is low, operation is easy, the whole process is carried out under the solid-phase condition, no solvent is needed, the degradation efficiency is good, and the method has good application and popularization prospects.

Description

Technical Field

[0001] The invention belongs to the technical field of organic solid waste treatment and comprehensive utilization, and specifically relates to a method for degrading residual antibiotics in macrolide antibiotic fermentation waste. Background Art

[0002] Macrolide antibiotics are a class of broad-spectrum antibacterial drugs that work by inhibiting bacterial protein synthesis. They usually contain a macrolide ring of 12 to 16 carbon atoms and are connected to a sugar group through a glycosidic bond. This type of drug mainly targets Gram-positive bacteria and some Gram-negative bacteria, such as Streptococcus pneumoniae and Staphylococcus aureus. Representative drugs of macrolide antibiotics include erythromycin, clarithromycin and azithromycin. These drugs are widely used in clinical practice to treat respiratory tract infections, skin and soft tissue infections, and Helicobacter pylori infections. However, bacterial resistance to macrolide antibiotics is becoming increasingly serious, mainly manifested as reduced affinity, which can be achieved through mechanisms such as bacterial ribosome modification or increased drug efflux. The main cause of resistance is the abuse of antibiotics and the discharge of antibiotic process waste.

[0003] The industrial production of macrolide antibiotics is to inoculate antibiotic-producing bacteria such as Streptomyces and Actinomycetes on a culture medium for cultivation, and to regulate the fermentation process so that antibiotics are produced through microbial fermentation. After the fermentation is completed, the fermentation broth is separated into solid and liquid, and the target antibiotic is present in the filtrate, while the filter cake left is the antibiotic residue. According to statistics, the main components of antibiotic residue include mycelium of some antibiotic-producing bacteria, metabolites produced during the fermentation process, a large amount of organic culture medium and degradation products of the culture medium, in addition to a small amount of residual antibiotics. If the antibiotic residue is not properly disposed of, the residual antibiotics and their metabolites in the environment alone will cause chronic toxicity and endocrine disruption to aquatic organisms and humans, and increase bacterial resistance.

[0004] Traditionally, the treatment methods for bacterial residues include incineration, landfill, feed and fertilizer. In recent years, the harmless treatment of antibiotic bacterial residues has attracted more and more attention, and hydrothermal treatment technology, electron beam irradiation technology, anaerobic fermentation, oxidative degradation and other technologies have also been increasingly used for the harmless treatment of antibiotic bacterial residues. Mechanochemistry, as an emerging and efficient technology, has many applications in metallurgy, material synthesis, extraction of natural products, drug synthesis and preparation, but has also shown great development potential in the field of organic pollutant degradation in recent years. Patent CN110951637A discloses a new method for treating erythromycin bacterial residues, firstly acidifying the erythromycin bacterial residues with strong acid, adjusting the pH to 6.5-7.5 and then concentrating with a reverse osmosis device, and the concentrated solution is pre-frozen, vacuum freeze-dried, and crushed to obtain erythromycin bacterial residue powder. The obtained fungus residue powder can be used as a nutrient component for erythromycin fermentation, replacing part of the soybean cake powder and adding it to the erythromycin fermentation medium. Although the invention solves the problem of erythromycin pollution and realizes the resource utilization of fungus residue, the operation process is cumbersome, and a large amount of phosphoric acid is used in the invention, which has certain safety hazards. Patent CN219792952U discloses a treatment device for antibiotic fermentation fungus residue, and the invention device includes a pre-regulation tank, a fully mixed anaerobic fermentation tank and a sedimentation tank connected in sequence. The fully mixed anaerobic fermentation tank in the device optimizes the water inlet form, and the fungus residue can be directly sent to the fully mixed anaerobic fermentation tank, without the need for other wastewater dilution and mixing, without the need for gas-liquid mixing, without the nozzle form, the structure is simpler, and the clogging problem after long-term operation is avoided, so that the fungus residue is internally circulated and mixed, without mechanical stirring, saving the original fungus residue heating cost. Although anaerobic fermentation has made resource utilization of fungus residue, a large amount of wastewater and harmful gases will be generated during the anaerobic fermentation process, and the residual antibiotics in the antibiotic fungus residue cannot be thoroughly degraded at the same time, and there are certain environmental hazards in the follow-up. Patent CN105624074A discloses a harmless treatment method for antibiotic bacterial residues. The invention adds glucose, microbial composite strains and grass powder to the antibiotic bacterial residues, mixes them, and cultivates them to form solid fermentation strains. Then, the strains, grass powder and fresh antibiotic bacterial residues are mixed in weight proportion and fermented for 72-96 hours to obtain high-protein antibiotic harmless fermented bacterial residues. The fermented product of the bacterial residues is dried, ground and crushed, and sieved through 60 meshes to obtain fermented high-protein bacterial powder. Although the invention realizes the degradation of antibiotics and the resource utilization of bacterial residues, the method takes a long time, and the selection of microbial composite strains is specific. Patent CN201611114029.8 discloses a harmless treatment method for fermented antibiotic bacterial residues. The invention uses thermophilic hydrolysis acid-producing bacteria to perform high-temperature anaerobic acid-producing fermentation treatment on fermented antibiotic bacterial residues, hydrolyzes and acidifies the bacterial residues, inactivates the antibiotic-producing bacteria in the bacterial residues, and degrades the residual antibiotics, and then performs biochemical treatment to make the antibiotic bacterial residues harmless and resourceful.Although this method can completely kill the antibiotic-producing bacteria in the bacterial residue, leaving no antibiotic residue, and the bacterial residue after biochemical treatment is free of the danger of drug-resistant bacteria and drug-resistant genes, the treatment time is long and a large amount of toxic and harmful gases and wastewater will be produced, increasing the cost of secondary treatment.

[0005] As antibiotic pollution becomes increasingly serious and there is a lack of effective treatment technologies and means for macrolide antibiotics in solid materials, the development of new technologies for eliminating macrolide antibiotic pollution in solids at low cost and high efficiency is of great significance for environmental protection and waste management. Summary of the invention

[0006] The purpose of the present invention is to completely degrade the residual macrolide antibiotics in the bacterial residue, and the degraded antibiotic bacterial residue can be reused in fermentation to achieve comprehensive utilization of resources. In order to overcome the problems of large amount of chemical reagents, complicated process, high cost, incomplete degradation, lack of reuse of antibiotic bacterial residue, etc. in the existing process of degrading antibiotic bacterial residue, a method for degrading residual antibiotics in macrolide antibiotic fermentation waste is proposed.

[0007] Based on the conclusions of previous basic research, the present invention uses variable valence transition metals and their salts as oxidants, and non-oxidizing metal oxides with water absorption capacity and solid electron transfer capacity and cheap as additives for the reaction system, and the two together constitute a ball milling aid. By using a planetary ball mill, a certain proportion of ball milling aid is added to the fungus residue, and ball milling is performed at a certain frequency for a period of time to achieve the purpose of directly degrading antibiotics. During the mechanochemical treatment process, mechanical force activates the transition metal salt in the ball milling aid to turn it into a strong oxidant, and through complexation with the co-oxidant and fungus residue biomass, the life of the free radical is extended, and the oxidative degradation of macrolide antibiotics is promoted. Since the present invention is all carried out in the solid phase, it is enough to avoid the interference of precipitation and complexes such as thiol and hydroxyl groups on the Fenton process, and the reagents used are low-priced, the method is simple and easy to implement. No external solution is required for washing after treatment, which is more environmentally friendly and economical.

[0008] To achieve the above object, the present invention adopts the following technical solution:

[0009] A method for degrading residual antibiotics in macrolide antibiotic fermentation waste comprises the following steps: weighing antibiotic bacterial residues, adding ball milling aids and ball milling media, adjusting the ball mill speed, setting the ball milling time, and performing HPLC content analysis on the antibiotic residues after extraction.

[0010] Furthermore, the antibiotic residue is a waste product from the fermentation of macrolide antibiotics, and is one of the following: erythromycin residue and avermectin residue.

[0011] Further, the ball milling aid includes an oxidant and an oxidant co-oxidant, wherein the oxidant is one or a mixture of ferric chloride, ferrous chloride, ferrous sulfate, ferrous sulfate, potassium ferrate, cupric chloride, cupric oxide, manganese dioxide, and iron powder, preferably ferric chloride; the oxidant co-oxidant is one of calcium oxide, magnesium oxide, zinc oxide, and silicon dioxide, preferably calcium oxide; wherein the mass of the oxidant accounts for 10%-90% of the total mass of the ball milling aid, preferably 40%. Further, the mass ratio of the ball milling aid to the mass of the antibiotic bacterial residue is 5%-90%, preferably 50%; the ball milling medium is stainless steel ball milling beads, and the ball-to-material ratio is 1:1-10:1, preferably 8:1.

[0012] Furthermore, the diameter of the stainless steel ball milling beads is 10 to 25 mm, preferably 15 mm; the ball milling frequency is 100 to 500 rpm, preferably 350 rpm; and the ball milling time is 50 to 250 min, preferably 150 min.

[0013] Compared with the prior art, the beneficial effects of the present invention are mainly reflected in:

[0014] (1) Compared with the traditional methods of incineration, landfill, feed and fertilizer, the present invention not only achieves cheap and efficient degradation of antibiotics, but also the treated fungus residue can be directly reused to ferment and produce antibiotics.

[0015] (2) The oxidant and auxiliary agent used in the present invention exist in large quantities in nature and will not cause secondary environmental pollution.

[0016] (3) The present invention is carried out under solid phase conditions, and no waste gas or waste liquid is generated. The solid powder is easy and convenient to store, and the treated mushroom residue powder can be directly used as a fermentation raw material.

[0017] (4) The degradation conditions of the present invention are simple to operate, short in processing time and high in degradation efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 This is a diagram showing the effect of oxidant and co-oxidant selection on erythromycin degradation;

[0019] Figure 2 The ratio of oxidant to co-oxidant and the ratio of ball milling aid to bacterial residue have an effect on the degradation of erythromycin;

[0020] Figure 3 The influence of ball-to-material ratio, ball milling speed, ball milling time and ball milling bead diameter on the degradation of erythromycin;

[0021] Figure 4 Evaluation of the antibacterial effect of the samples (calculated based on the effect on the growth of Staphylococcus aureus). DETAILED DESCRIPTION

[0022] The present invention is further described below in conjunction with the embodiments and the accompanying drawings, but the protection scope of the present invention is not limited thereto.

[0023] Example 1

[0024] The degradation rate of erythromycin was determined by the following method: the sample was extracted with an extract (5 mL 0.01 M / LTris-0.02 M / L CaCl2, pH = 6) and vortexed at 2500 rpm for 2 min, then the extractant (15 mL) was added to the above 50 mL centrifuge tube, and vortexed for 3 min to ensure complete dispersion, and finally centrifuged at 10000 rpm for 5 min. The lower layer of liquid after centrifugation was dried and re-dissolved with 10 mL methanol solution, then passed through a 0.45 um organic membrane, and transferred to a 2 mL amber glass vial for liquid phase analysis. The erythromycin content was determined by high performance liquid chromatography using an Agilent C 18 (250mm×4.6mm, 1.7μm) column, column temperature maintained at 25°C, isocratic elution, mobile phase A (0.01M, KH2PO4) / B (acetonitrile) = 60%: 40%, injection volume 10uL, flow rate 0.68mL / min, running time 45min. The erythromycin content was obtained according to the standard curve external standard method, and then the residual amount of erythromycin in the sample (g / Kg) was calculated.

[0025] Degradation rate (erythromycin) % = (antibiotic content in bacterial residue after degradation / antibiotic content in bacterial residue before degradation) * 100%

[0026] Example 2

[0027] Taking erythromycin residue as the research object, 5g of antibiotic residue was weighed, 1.5g of ferric chloride (FeCl3), 1.5g of calcium oxide (CaO), and 63g of 15mm stainless steel balls were added. The ball mill speed was adjusted to 350rpm and the ball milling time was 150min. The antibiotic residue after ball milling was analyzed by HPLC content after extraction, and the erythromycin degradation rate in the residue was calculated according to the method described in Example 1.

[0028] Example 3

[0029] Taking erythromycin residue as the research object, 5g of antibiotic residue was weighed, 1.5g of ferrous chloride (FeCl2), 1.5g of CaO, and 63g of 15mm stainless steel balls were added. The ball mill speed was adjusted to 350rpm and the ball milling time was 150min. The antibiotic residue after ball milling was analyzed by HPLC content after extraction, and the erythromycin degradation rate in the residue was calculated according to the method described in Example 1.

[0030] Example 4

[0031] Taking erythromycin residue as the research object, 5g of antibiotic residue was weighed, 1.5g of ferric sulfate (Fe2(SO4)3), 1.5g of CaO, and 63g of 15mm stainless steel balls were added. The ball mill speed was adjusted to 350rpm and the ball milling time was 150min. The antibiotic residue after ball milling was analyzed by HPLC content after extraction, and the erythromycin degradation rate in the residue was calculated according to the method described in Example 1.

[0032] Example 5

[0033] Taking erythromycin residue as the research object, 5g of antibiotic residue was weighed, 1.4g of ferrous sulfate (FeSO4), 1.5g of CaO, and 63g of 15mm stainless steel balls were added. The ball mill speed was adjusted to 350rpm and the ball milling time was 150min. The antibiotic residue after ball milling was analyzed by HPLC content after extraction, and the erythromycin degradation rate in the residue was calculated according to the method described in Example 1.

[0034] Example 6

[0035] Taking erythromycin residue as the research object, 5g of antibiotic residue was weighed, 1.5g of copper chloride (CuCl2), 1.5g of CaO, and 63g of 15mm stainless steel balls were added. The ball mill speed was adjusted to 350rpm and the ball milling time was 150min. The antibiotic residue after ball milling was analyzed by HPLC content after extraction, and the erythromycin degradation rate in the residue was calculated according to the method described in Example 1.

[0036] Example 7

[0037] Taking erythromycin residue as the research object, 5g of antibiotic residue was weighed, and 1.5g of potassium ferrate (K2FeO4), 1.5g of CaO, and 63g of 15mm stainless steel balls were added. The ball mill speed was adjusted to 350rpm and the ball milling time was 150min. The antibiotic residue after ball milling was analyzed by HPLC content after extraction, and the erythromycin degradation rate in the residue was calculated according to the method described in Example 1.

[0038] Example 8

[0039] Taking erythromycin residue as the research object, 5g of antibiotic residue was weighed, 1.5g of iron powder, 1.5g of CaO, and 63g of 15mm stainless steel balls were added. The ball mill speed was adjusted to 350rpm and the ball milling time was 150min. The antibiotic residue after ball milling was analyzed by HPLC content after extraction, and the erythromycin degradation rate in the residue was calculated according to the method described in Example 1.

[0040] Example 9

[0041] Taking erythromycin residue as the research object, 5g of antibiotic residue was weighed, 1.5g of manganese dioxide, 1.5g of CaO, and 63g of 15mm stainless steel balls were added. The ball mill speed was adjusted to 350rpm and the ball milling time was 150min. The antibiotic residue after ball milling was analyzed by HPLC content after extraction, and the erythromycin degradation rate in the residue was calculated according to the method described in Example 1.

[0042] Example 10

[0043] Taking erythromycin residue as the research object, 5g of antibiotic residue was weighed, 1.5g of copper oxide, 1.5g of CaO, and 63g of 15mm stainless steel balls were added. The ball mill speed was adjusted to 350rpm and the ball milling time was 150min. The antibiotic residue after ball milling was analyzed by HPLC content after extraction, and the erythromycin degradation rate in the residue was calculated according to the method described in Example 1.

[0044] like Figure 1 As shown in A, it can be found that the degradation effects of antibiotics in bacterial residues are quite different when different oxidants are used, among which divalent and trivalent iron salts have the best degradation effects, and ferric chloride is significantly better than other iron salts, which is in line with the law of Fenton oxidation.

[0045] Embodiment 11

[0046] Taking erythromycin residue as the research object, 5g of antibiotic residue was weighed, 1.5g of FeCl3, 1.5g of zinc oxide (ZnO), and 63g of 15mm stainless steel balls were added. The ball mill speed was adjusted to 350rpm and the ball milling time was 150min. The antibiotic residue after ball milling was analyzed by HPLC content after extraction, and the erythromycin degradation rate in the residue was calculated according to the method described in Example 1.

[0047] Example 12

[0048] Taking erythromycin residue as the research object, 5g of antibiotic residue was weighed, 1.5g of FeCl3, 1.5g of magnesium oxide (MgO), and 63g of 15mm stainless steel balls were added. The ball mill speed was adjusted to 350rpm and the ball milling time was 150min. The antibiotic residue after ball milling was analyzed by HPLC content after extraction, and the erythromycin degradation rate in the residue was calculated according to the method described in Example 1.

[0049] Embodiment 13

[0050] Taking erythromycin residue as the research object, 5g of antibiotic residue was weighed, 1.5g of FeCl3, 1.5g of silicon dioxide (SiO2), and 63g of 15mm stainless steel balls were added. The ball mill speed was adjusted to 350rpm and the ball milling time was 150min. The antibiotic residue after ball milling was analyzed by HPLC content after extraction, and the erythromycin degradation rate in the residue was calculated according to the method described in Example 1.

[0051] like Figure 1 As shown in B, it can be found that the use of different co-oxidants also affects the degradation effect. The role of the auxiliary oxidant is to absorb water and assist solid-phase electron transfer, so calcium oxide with water absorption and electron transfer effects has the best effect.

[0052] Embodiment 14

[0053] Taking erythromycin residue as the research object, 5g of antibiotic residue was weighed, and different proportions of FeCl3 and CaO were added to maintain the total mass of 3g. 63g of 15mm stainless steel balls were added, and the ball mill speed was adjusted to 350rpm and the ball milling time was 150min. The antibiotic residue after ball milling was analyzed by HPLC after extraction, and the ratio of oxidant and auxiliary agent was optimized by the degradation rate of erythromycin, such as Figure 2 As shown in A, the results show that the degradation efficiency changes with the increase of CaO amount. When FeCl3 accounts for 40% of the total reagent, the degradation rate is the largest, indicating that the oxidant can be best activated under this condition, and there are enough additives to mediate the electron transfer of the solid phase system during the reaction.

[0054] Embodiment 15

[0055] Erythromycin residue was used as the research object. 5g of antibiotic residue was weighed and mixed with FeCl3 and CaO in a ratio of 2:3 (FeCl3 accounted for 40% of the total mass). The total amount of ball milling aid was changed to 63g of 15mm stainless steel balls, the ball mill speed was adjusted to 350rpm, and the ball milling time was 150min. The antibiotic residue after ball milling was analyzed by HPLC after extraction, and the ratio of ball milling aid to residue was optimized by the degradation rate of erythromycin. Figure 2 As shown in B, the results show that the degradation efficiency changes with the increase of the amount of ball milling aid. When the ball milling aid accounts for 50% of the total ground material, the degradation rate is the largest and will not increase with the addition amount, indicating that under this condition, the oxidant is sufficient to catalyze the oxidation reaction and oxidize all antibiotics. In order to increase the processing volume, 50% is selected as the amount of ball milling aid.

[0056] Example 16

[0057] Erythromycin residue was used as the research object. Different masses of antibiotic residue were weighed, and 40% of the residue mass of FeCl3 and CaO were added. The mass of oxidant and co-oxidant was 2:3, 63g of 15mm stainless steel ball was used, and the ball-to-material ratio was changed to 1:1, 2:2, 4:1, 8:1, 10:1, 20:1, respectively. The ball mill speed was adjusted to 350rpm, and the ball milling time was 150min. The antibiotic residue after ball milling was analyzed by HPLC after extraction, and the ball-to-material ratio was optimized by the degradation rate of erythromycin. Figure 3As shown in A in the figure, the results show that as the ball-to-material ratio increases, the degradation efficiency first increases and then decreases, and it is the largest when the ball-to-material ratio is 8:1, indicating that under this condition, there is enough movement space in the ball mill jar, and the ball mill can provide sufficient mechanical energy to catalyze the oxidation reaction.

[0058] Embodiment 17

[0059] Erythromycin residue was used as the research object. 5g antibiotic residue was weighed, and 1.0g FeCl3, 1.5g CaO, and 63g 15mm stainless steel balls were added. The ball mill speed was adjusted to 100rpm, 150rpm, 200rpm, 250rpm, 300rpm, 350rpm, 400rpm, 450rpm, and 500rpm. The ball milling time was 150min. The antibiotic residue after ball milling was analyzed by HPLC after extraction, and the ball milling time was optimized by the erythromycin degradation rate. Figure 3 As shown in B, the results show that the degradation efficiency increases with the increase of ball milling frequency, and it reaches the maximum and equilibrium when the ball milling frequency is 350 rpm, indicating that sufficient reaction energy is provided under this condition, while avoiding energy conversion into heat energy and resulting in energy waste.

[0060] Embodiment 18

[0061] Erythromycin residue was used as the research object. Weigh 5g of antibiotic residue, add 1.0g FeCl3, 1.5g CaO, and 63g of stainless steel balls with diameters of 5mm, 10mm, 15mm, 20mm, and 25mm, respectively. Adjust the ball mill speed to 350rpm and the ball milling time to 150min. The antibiotic residue after ball milling was analyzed by HPLC after extraction, and the diameter of the stainless steel ball was optimized by the erythromycin degradation rate, such as Figure 3 As shown in D, the results show that with the increase of ball milling bead diameter, the mechanical force provided is significantly improved, and the degradation rate increases. However, when the ball milling bead diameter is greater than 15 mm, the kinetic energy provided is significantly reduced due to the reduction of movement space, so the degradation rate decreases. Therefore, the optimal ball milling bead diameter is 15 mm.

[0062] Embodiment 19

[0063] Take erythromycin residue as the research object, weigh 5g antibiotic residue, add 1.0g FeCl3, 1.5g CaO, 63g 15mm stainless steel ball. Adjust the ball mill speed to 350rpm. Set the ball milling time to 50min, 100min, 150min, 200min, 250min. The antibiotic residue after ball milling is analyzed by HPLC after extraction, and the ball milling time is optimized by the degradation rate of erythromycin. Figure 3As shown in C, the results show that the degradation efficiency increases with the increase of ball milling time. When the ball milling time is 150 minutes, the degradation rate is the largest and balanced, indicating that sufficient reaction energy is provided under this condition. In order to increase the efficiency, 150 minutes is preferred.

[0064] Embodiment 20

[0065] The optimal degradation process was as follows: 5 g of antibiotic residue was weighed, 1.0 g of FeCl3, 1.5 g of CaO, and 63 g of 15 mm stainless steel balls were added. The ball mill speed was adjusted to 350 rpm. The ball milling time was set to 150 min. The antibiotic residue after ball milling was analyzed by HPLC after extraction, and the degradation rate of erythromycin was obtained by comparing the concentration before ball milling. The experiment was repeated 3 times, and the degradation rate of erythromycin was measured to be 99.53 ± 0.12%. Further analysis by LC-MS showed that the degradation products were mainly open-ring and oxidized erythromycin without antibiotic activity, as shown in Table 1.

[0066] Table 1 Erythromycin degradation products confirmed

[0067]

[0068] Embodiment 21

[0069] Degradation effect of avermectin: weigh 5g antibiotic bacteria residue, add 1.0g FeCl3, 1.5g CaO, 63g 15mm stainless steel ball. Adjust the ball mill speed to 350rpm. Set the ball milling time to 150min. The antibiotic bacteria residue after ball milling is analyzed by HPLC content after extraction, and the degradation rate of avermectin is obtained by comparing the avermectin concentration before ball milling. The experiment is repeated 3 times, and the degradation rate of avermectin in the avermectin bacteria residue is 99.65±0.07%. Further, as shown in Table 2, the types of degradation products are mainly open-loop and oxidized avermectins without antibiotic activity.

[0070] Table 2 Avermectin and its main degradation products

[0071]

[0072]

[0073] Embodiment 22

[0074] The antibacterial activity of degraded bacterial residues was evaluated by taking the erythromycin residues degraded by the method of Example 20, and using Staphylococcus aureus to evaluate the antimicrobial removal of erythromycin residues. First, prepare a 100 mg / L erythromycin standard solution, then weigh 5 g of the sample and dissolve it in 30 mL of water, vortex at 2500 rpm for 3 min, and then centrifuge it in a centrifuge at 4000 rpm for 20 min. Take the supernatant and filter it through a 0.45 μm filter membrane in a clean bench to remove the influence of microorganisms in the reaction solution. Then, add different proportions of the erythromycin residue supernatant filtrate and grow it together with Staphylococcus aureus, and then use SHIMADZU UV-1800 to measure the OD of Staphylococcus aureus at intervals. 600 Values, such as Figure 4 As shown. The experimental results show that the untreated erythromycin residue group almost completely inhibits the growth of Staphylococcus aureus, and the growth of Staphylococcus aureus within 22 hours is less than 30% of the blank group. In Example 20, the growth trend of Staphylococcus aureus was only slightly affected. Although it was slightly inhibited in the early stage, the growth of Staphylococcus aureus after 24 hours was basically consistent with that of the blank group. From the perspective of antibacterial performance, the anti-antibiotic effect of the treatment process described in Example 20 on erythromycin residue is obviously better than that before treatment, indicating that this method can actually remove antibiotics and avoid their conversion into substances with antibiotic activity, completely eliminate their antibacterial activity, and facilitate the reuse of residues.

[0075] Embodiment 23

[0076] Take 60g of peptone, the degraded bacterial residue and the original bacterial residue described in Example 20, 20g / L peptone, 0.2g / L KH2PO4, and 0.25g / L magnesium sulfate to prepare erythromycin shake flask fermentation medium. After sterilization, take 50mL of fermentation culture solution to a 250mL conical flask. The strain selected was BNCC Saccharopolyspora erythraea 153143, which was activated. A 1cm piece of erythraea was dug out from the grown plate. 2 The spores were inoculated, and after the inoculation, they were fermented at 34°C and 220rpm for 120h. Among them, 1% n-propanol was added when the shake flask fermentation reached 24h. After the fermentation, the erythromycin A content was measured by HPLC. The experimental results are shown in Table 3 below. The results show that the original bacterial residue and the anti-degradable bacterial residue described in Example 20 can be used as culture medium materials for erythromycin fermentation. However, after the treated bacterial residue was inoculated with BNCC red saccharopolyspora, its growth was not inhibited, and the degradation of the bacterial residue to enrich protein provided a high-quality nitrogen source for mycelial growth. The erythromycin yield was significantly higher than the fermentation level of peptone and undegraded bacterial residue as a nitrogen source, indicating that the above-mentioned fermented bacterial residue can be used as a culture medium nitrogen source for erythromycin culture, and the effect is better than that of undegraded bacterial residue.

[0077] Table 3: Effect of erythromycin fermentation after bacterial residue degradation culture

[0078]

Claims

1. A method for degrading residual antibiotics in macrolide antibiotic fermentation waste, characterized in that: The method comprises the following steps: weighing antibiotic bacterial residue, adding ball milling aid and ball milling medium, adjusting the rotation speed of the ball mill, setting the ball milling time, and analyzing the residual amount of antibiotics in the antibiotic bacterial residue after ball milling by HPLC content analysis after extraction.

2. The method for degrading residual antibiotics in macrolide antibiotic fermentation waste according to claim 1, characterized in that: Antibiotic residues are waste products from the fermentation of macrolide antibiotics, and are one of the following: erythromycin residues and avermectin residues.

3. The method for degrading residual antibiotics in macrolide antibiotic fermentation waste according to claim 1, characterized in that: The ball milling aid comprises an oxidant and an oxidant aid, wherein the oxidant is one or a mixture of ferric chloride, ferrous chloride, ferric sulfate, ferrous sulfate, potassium ferrate, cupric chloride, cupric oxide, manganese dioxide, and iron powder, preferably ferric chloride; the oxidant aid is one of calcium oxide, magnesium oxide, zinc oxide and silicon dioxide, preferably calcium oxide; wherein the mass of the oxidant accounts for 10%-90% of the total mass of the ball milling aid, preferably 40%.

4. The method for degrading residual antibiotics in macrolide antibiotic fermentation waste as claimed in claim 3, characterized in that: The mass ratio of the ball milling aid to the antibiotic bacterial residue is 5% to 90%, preferably 50%; the ball milling medium is stainless steel ball milling beads, and the ball-to-material ratio is 1:1 to 10:1, preferably 8:

1.

5. The method for degrading residual antibiotics in macrolide antibiotic fermentation waste as claimed in claim 4, characterized in that: The diameter of the stainless steel ball milling beads is 10-25 mm, preferably 15 mm; the ball milling frequency is 100-500 rpm, preferably 350 rpm; the ball milling time is 50-250 min, preferably 150 min.

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