CN112617012A

CN112617012A - Animal feed additive with biological activity and heavy metal removal function and preparation method thereof

Info

Publication number: CN112617012A
Application number: CN202011124151.XA
Authority: CN
Inventors: 陈丽春; 张诗雨; 赵会敏
Original assignee: Zhejiang Gongshang University
Current assignee: Zhejiang Gongshang University
Priority date: 2020-10-20
Filing date: 2020-10-20
Publication date: 2021-04-09

Abstract

The invention discloses an animal feed additive with biological activity and heavy metal removal, which is prepared from the following raw materials in parts by weight: 20-40 parts of bamboo leaf carbon black, 5-15 parts of white peony root extract concentrated solution, 8-10 parts of bamboo leaf extract concentrated solution, 10-60 parts of chamomile extract concentrated solution, 10-20 parts of folium isatidis extract concentrated solution and 10-30 parts of sodium starch octenyl succinate. The invention also discloses a preparation method, which comprises the steps of mixing the raw materials, performing ultrasonic treatment and high-pressure homogenization to obtain the stable microemulsion with the average dispersed phase particle size of 300-. The bamboo leaf carbon black is used as a base material, is subjected to compound modification and is combined with various natural products to prepare the animal feed additive with the heavy metal removal function and the biological activity function, can be used for feeding various animals, has high heavy metal removal performance and high stability, and contains nutrient substances and biological activity substances such as bamboo leaf flavone and apigenin and the like, so that the immunity of the animals is improved.

Description

Animal feed additive with biological activity and heavy metal removal function and preparation method thereof

Technical Field

The invention belongs to the technical field of feed additives, and particularly relates to an animal feed additive with biological activity and capable of removing heavy metals and a preparation method thereof.

Background

Bamboo is a perennial gramineous plant, and the stems and leaves of bamboo contain various flavonoid compounds, phenolic compounds, proteins and saccharides, tea polyphenols, amino acids and other components. The flavone compounds in the bamboo leaves mainly exist in the form of glycosides, and four kinds of carbon glycoside flavones mainly exist, namely isoorientin, orientin, isovitexin and vitexin. Flavonoids (Flavonoids) are a class of secondary metabolites that are widely found in medicinal plants and plant fruits, mainly in the aglycone form. The flavonoid has excellent natural oxidation resistance and free radical scavenging property. Compared with common flavone, the bamboo leaf extract has excellent anti-free radical and antioxidant properties. The bamboo leaf extract has strong capability of eliminating active oxygen free radicals. Furthermore, the bamboo leaf extract has a broad bacteriostatic action on microorganisms, and has a bacteriostatic action by destroying the cell walls and cell membranes of microorganisms. The bamboo leaf extract can also block nitrite and secondary amine in stomach from nitrosation reaction. Chamomile (M)atricaria chamomilla L) Also called Matricaria chamomilla, Compositae Matricaria herb, and flos Matricariae Chamomillae flavonoid mainly contains apigenin, apigenin-7-O-glucoside, rutin, chlorogenic acid, quercetin, etc. Apigenin (Apioside) is an apigenin-conjugated glycoside compound, and is an antioxidant active substance in flos Matricariae Chamomillae extract. However, the application of natural flavonoids is limited by complex structure, many action sites, easy oxidation instability, poor solubility, low water solubility, low bioavailability and the like. The microemulsion technology is a transparent or semitransparent and isotropic thermodynamic stable system formed by water, oil, surfactant and cosurfactant in a proper proportion, has strong solubilizing property and can be used in the industries of medicines, foods, feeds and the like。

At present, the feed generally contains heavy metals with high content, and the method for removing the heavy metals accumulated in the animal body by using the feed is few. The existing method has low treatment efficiency, high cost, narrow application range and limitation. Cadmium (Cadmium) is a common heavy metal, is widely applied to industry, and is harmful to organisms due to environmental pollution caused by industrial and agricultural production, and the toxicity of Cadmium is closely related to oxidative damage. Previous studies have shown that in the process of cadmium toxicological damage, lipid peroxidation metabolites of serum, liver and kidney, such as Malondialdehyde (MDA), are significantly increased, and simultaneously, the activities of enzymes resisting lipid peroxidation, such as superoxide dismutase (SOD) and glutathione peroxidase (GSH-PX), are reduced.

The surfactant emulsifying system is a metastable system with stable dynamics and unstable thermodynamics, the solid particle stabilizer forms irreversible adsorption once entering an interface, and the solid particles wrap liquid drops, thereby effectively preventing unstable approaches such as coalescence, drainage and the like of the liquid drops. The plant carbon black (China national standard number: 08.138) is approved by the Ministry of public health of the people's republic of China to be used as a food additive, such as industrial production, medicine, food additive, environmental protection and the like. Carbon black is an insoluble particle, usually used in the form of a suspension. The natural materials suitable for serving as the particle stabilizer are very limited, and the flavonoid and starch particles are used for preparing the stabilizer from insoluble particles, so that the ever-increasing requirements on the production of food, medicine, agriculture and cosmetics cannot be met.

Disclosure of Invention

Aiming at the problems in the prior art, the invention aims to provide an animal feed additive with bioactivity and capable of removing heavy metals and a preparation method thereof. The invention adopts natural products as processing raw materials, has no toxicity, harm and residue risk, and obtains the animal feed additive which contains flavonoid extract, has uniform particle size and improves bioavailability by emulsifying and adsorbing the bamboo leaf carbon black. The animal feed additive can be used in the fields of food, feed, cosmetics, medicine, biochemical engineering and the like, and is particularly suitable for the development of animal feeds for removing heavy metals and the like. Effectively reduces the enrichment of the animals on the heavy metals accumulated in the bodies in the feeding process, contains rich nutrient substances and bioactive substances such as antioxidant components of flavone, apigenin and the like, and increases the immunity of the animals. In addition, the raw materials are wide in source, most raw materials are domestic wastes, and the resource utilization of the wastes is greatly realized.

The invention is realized by the following technical scheme:

the animal feed additive with bioactivity and capable of removing heavy metals is characterized by being prepared from the following raw materials in parts by weight: 20-40 parts of bamboo leaf carbon black, 5-15 parts of white peony root extract concentrated solution, 8-10 parts of bamboo leaf extract concentrated solution, 10-60 parts of chamomile extract concentrated solution, 10-20 parts of folium isatidis extract concentrated solution and 10-30 parts of sodium starch octenyl succinate.

The animal feed additive with biological activity and heavy metal removal is characterized in that the bamboo leaf carbon black is prepared by drying, high-temperature carbonization and activation refining of bamboo, and the microstructure is in a pore shape with the particle size of 300-.

The animal feed additive with bioactivity and capable of removing heavy metals is characterized in that the chamomile extract concentrated solution is prepared from chamomile, chrysanthemum morifolium and blood chrysanthemum serving as raw materials.

The animal feed additive with bioactivity and capable of removing heavy metals is characterized in that the using amount of the additive accounts for 1-15% of the total amount of the animal feed.

The preparation method of the animal feed additive with bioactivity and heavy metal removal is characterized by comprising the following steps:

1) weighing bamboo leaf carbon black in a formula amount, adding the bamboo leaf extract concentrated solution, sequentially dropwise adding the white paeony root extract concentrated solution, the chamomile extract concentrated solution and the folium isatidis extract concentrated solution in the formula amount at the temperature of 40-70 ℃ under the condition of magnetic stirring, and mixing for 2-4h to obtain a bamboo leaf carbon black plant active carrier;

2) carrying out ultrasonic and high-pressure homogenization on the bamboo leaf carbon black plant active carrier prepared in the step 1) and sodium starch octenyl succinate in a formula amount at the temperature of 30-50 ℃ to obtain a stable nanoparticle emulsion with the average dispersed phase particle size of 300-;

3) pre-freezing the nano particle emulsion prepared in the step 2) for 24 hours at the temperature of-18 ℃, and then carrying out vacuum freeze drying to obtain the animal feed additive nano particles with bioactivity and heavy metal removal.

The preparation method of the animal feed additive with biological activity and heavy metal removal is characterized in that the rotating speed of magnetic stirring in the step 1) is 500-1000 rpm.

The preparation method of the animal feed additive with bioactivity and heavy metal removal is characterized in that the ultrasonic power in the step 2) is 400-800W, the high-pressure homogenization condition is that the homogenization pressure is 0.1-80 MPa, and the homogenization time is 2-10 min

Compared with the prior art, the invention has the following beneficial effects:

1) the bamboo leaf carbon black is used as a substrate, and the excessive heavy metal content in animal feeding can be effectively avoided by adsorbing natural flavonoid bioactive substances, and the quality of the meat of poultry is improved;

2) the animal feed additive with biological activity and heavy metal removal, which is prepared by taking the bamboo leaf carbon black as a base material through composite modification and mixing with various natural products, can be used for feeding various animals. In addition, the raw materials are wide in source, most raw materials are domestic wastes, and the resource utilization of the wastes is greatly realized;

3) the invention uses the natural porous structure of bamboo leaf carbon black as the carrier of biological active substance, such as flavone, apigenin, etc. The soluble nano-particles are prepared by utilizing layer-by-layer self-assembly and taking sodium starch octenyl succinate as an outer wall material, so that the problem of the insolubility of bamboo leaf carbon black and the influence on the nutrient absorption of intestinal tracts is solved. The requirements of natural materials as bioactive substance carriers in the production of food, medicine, agriculture and cosmetics are met;

4) the product of the invention has a spatial network structure and strong stability, can effectively reduce the oxidative stress, liver injury and the like of heavy metal on organisms through animal experiments, and is used for various animals, particularly for poultry and fish.

Drawings

FIG. 1 is a graph showing the change in water intake (a), food intake (b), weight gain (c) and liver coefficient (d) of a mouse;

FIG. 2 shows the effect of carbon black of bamboo leaves on the content of heavy metal Cd in liver (a) and kidney (b);

FIG. 3 shows the effect of carbon black of bamboo leaves on the contents of liver superoxide dismutase (SOD) (a) and malonaldehyde MDA (b);

FIG. 4 shows the daily food intake (a), water intake (b) and weight change (c) of the mice;

FIG. 5 shows the effect of carbon black of bamboo leaves on liver superoxide dismutase SOD (a) and malonaldehyde MDA (b);

FIG. 6 shows the effect of carbon black of bamboo leaves on alanine Aminotransferase (ALT), aspartate Aminotransferase (AST) and alkaline phosphatase (AKP);

FIG. 7 shows the effect of carbon black of bamboo leaves on the LDH content (a) of lactate dehydrogenase and the LPO content (b) of lipid peroxide.

Detailed Description

The present invention will be described in further detail with reference to specific examples, and specific embodiments will be given below.

Example 1

Mixing dry chamomile, Hangzhou white chrysanthemum and snow chrysanthemum according to the mass ratio of 1:2:1, crushing, sieving by a 40-mesh sieve, and mixing the materials according to the material-liquid ratio of 10 kg: adding 50% ethanol solution into 40L of the above extract, and ultrasonic extracting at 50 deg.C for 60 min to obtain extract containing flos Matricariae Chamomillae.

Adsorbing with macroporous adsorbent resin with polystyrene skeleton, and eluting with 75% ethanol 4 times the column volume. Separating the eluate with ultrafiltration membrane, and concentrating under reduced pressure to obtain 30L of concentrated extract.

20-40 parts of bamboo leaf carbon black, 5-15 parts of white paeony root extract concentrated solution, 8-10 parts of bamboo leaf extract concentrated solution, 10-60 parts of chamomile extract concentrated solution, 10-20 parts of folium isatidis extract concentrated solution and 10-30 parts of sodium starch octenyl succinate are subjected to ultrasonic treatment and high-pressure homogenization at the temperature of 30-50 ℃ to obtain stable emulsion with the average dispersed phase particle size of 300-.

Wherein, the conditions for separating and purifying the white peony root extract concentrated solution, the bamboo leaf extract concentrated solution and the dyers woad leaf extract concentrated solution are that the macroporous absorption resin with a polyphenyl propylene framework is adopted for absorption, 75 percent ethanol with 5 to 10 times of column volume is used for elution, the eluent is separated by an ultrafiltration membrane, and the concentrated solution is obtained after decompression and concentration.

Example 2

Selecting flos Matricariae Chamomillae, flos Chrysanthemi, and snow Chrysanthemum as raw materials, mixing at a mass ratio of 1:1:1, oven drying at 30-40 deg.C, pulverizing, and sieving with 30 mesh sieve. Extracting with 0-80% ethanol solution at a ratio of 1 Kg: 15L-1 Kg: 25L under the assistance of ultrasonic wave for 40-60 min to obtain extract containing flos Matricariae Chamomillae total flavonoids. Filtering the extractive solution with 160 mesh filter to obtain clarified flos Matricariae Chamomillae total flavone extractive solution. Adsorption and elution by macroporous adsorption resin: adsorbing the chamomile total flavone concentrated solution by using macroporous adsorption resin at the temperature of 20-40 ℃ and the flow rate of 0.4-4BV/h, washing impurities by using distilled water with the volume of 3-6 times of the column volume, and then eluting by using ethanol with the volume of 3-10 times of the column volume and 15-95%; separating the eluate with ultrafiltration membrane to obtain transparent and clear flos Matricariae Chamomillae total flavone extract.

Experimental example 3

Reagent: ICR mice, 6 week male mice, provided by shanghai cleiss experimental animal center; bamboo leaf carbon black is provided by Wanglin Biotech, Inc.; an active carbon fine chemical cleaning agent; cadmium chloride, sodium carboxymethylcellulose, glacial acetic acid, biuret, bovine serum albumin, sodium hydroxide and copper sulfate are all from chemical reagents of the national drug group, and the analytical purity is high; superoxide dismutase (SOD), Glutathione (GSH), Malondialdehyde (MDA), alkaline phosphatase (AKP), glutamic-oxaloacetic transaminase (AST), glutamic-pyruvic transaminase (ALT), Lactate Dehydrogenase (LDH) and Lipid Peroxide (LPO) kits are purchased from Nanjing to build a bioengineering institute. All water was deionized water for the experiment.

The instrument comprises the following steps: SynergyH4 microplate reader Berton instruments Inc., USA; SUPER T21 high speed refrigerated centrifuge Shanghai sperm macro laboratory Equipment Co., Ltd; the rotary evaporator RE-2000 Shanghai Yangrong biochemical instrument factory; magnetic stirrers and homogenizers Ika (Guangzhou) instruments, Inc.; XPE-205 electronic balance Mettler-Torledo International trade (Shanghai) Inc.

Experimental methods

Solution preparation: preparing heavy metal drinking water: 0.0915g of cadmium chloride was weighed out, dissolved in 800mL of membrane-passing water and made to volume of 1L.

Animal feeding: ICR male mice for 6 weeks are adapted to the environment for one week, the growth conditions of the mice are closely observed, and the daily water intake and food intake are recorded and weighed. The raising temperature is 20-25 ℃, the humidity is about 50%, the ventilation is good, and the influence of known pollutants is avoided.

Bamboo leaf carbon black short-term exposure heavy metal model: the experiment was divided into 5 groups of 20 each: blank control (Water), heavy metal Cd (solution concentration).., heavy metal Water treatment (HM); the test groups (T3, T4 and T5) were perfused with bamboo leaf carbon Black (BCP) at doses of 2.81, 5.62 and 11.24g/kg, respectively, and the volume was 20mL/kg, and the lavage was continued for 1 week, and half of the samples were treated after the last lavage. The other half was further gavaged and after a further week the samples were processed.

Different types of carbon black exposure animal models: the experiment was divided into 3 groups of 10 each: blank control (Water), no treatment; activated carbon control (AC), gavage activated carbon (11.24 g/Kg) (AC 30 ppm); bamboo leaf carbon black group (BCP): and (3) perfusing bamboo leaf carbon black (11.24 g/Kg) (BCP 30 ppm) into the stomach, wherein the perfusing amount of the mouse is 20mL/Kg, continuously perfusing the stomach for 30 days, and dissecting the sample after cutting grains for 18 hours after the last perfusion.

Serum and liver and kidney indexes: at the end of the experiment, blood is taken from the orbit of the anesthetized animal, the blood sample is stood for 30min at room temperature and then centrifuged at 3500r/min for 15min, and serum is separated and subpackaged. The liver and kidney were separated, weighed and 0.1g each was added to 900. mu.l PBS and mixed well to make a homogenate. The kit is used for detecting superoxide dismutase (SOD), Malondialdehyde (MDA) and Glutathione (GSH), and particularly operates according to the relevant requirements of the kit. Taking part of serum to be used for the determination of kits such as alkaline phosphatase (AKP), glutamic-oxaloacetic transaminase (AST), glutamic-pyruvic transaminase (ALT), Lactate Dehydrogenase (LDH), Lipid Peroxide (LPO) and the like, and specifically operating the related requirements of the reference kit.

Heavy metal content detection

The inductively coupled plasma mass spectrometer is used for detecting the content of heavy metals. Accurately weighing the sample, adding water to dissolve the sample in a 100mL beaker, adding 2mL nitric acid, transferring the solution to a 100mL volumetric flask, mixing uniformly, and diluting with pure water to a scale. The solution is filtered by a water-based 0.22 mu m mixed cellulose membrane, and is placed in a polypropylene centrifuge tube, and an instrument is adjusted for detection, wherein specific parameters are shown in Table 1. And simultaneously detecting the standard substance, and comparing the standard substance with the standard substance to obtain the concentration of the heavy metal in the sample.

TABLE 1 inductively coupled plasma Mass spectrometer Main operating parameters

Parameters of the instrument	Parameter value	Parameters of the instrument	Parameter value
				RF power	1500W	Number of repetitions	3
Plasma gas flow rate	15L/min	Measuring mode	Jumping peak
				Auxiliary gas flow	1.0L/min	Measuring point	3
Flow of carrier gas	0.7L/min	Sample lifting rate	0.4mL•min
				Compensating gas flow	0.39 L/min	Peristaltic pump	0.1rps
Depth of sampling	8mm	Resolution ratio	0.75±0.1amu
				Integration time	Cd：0.3s	Temperature of atomization	2°C

And (3) detecting the protein content: and (3) measuring the protein content by a biuret method. Determination of the standard curve: the 18 tubes were divided into two groups, and 0, 0.2, 0.4, 0.6, 0.8, 1.0mL of standard protein solution was added, water was made up to 1mL, and then 4mL of biuret reagent was added. After shaking sufficiently, the mixture was left at room temperature (20 to 25 ℃) for 30min and subjected to colorimetric determination at 540 nm. The first tube without protein solution was used as a blank. Taking the average value of the three groups of measurements, and drawing a standard curve by taking the content of the protein as an abscissa and the light absorption value as an ordinate. Centrifuging the processed tissue sample at 3500r/min for 10min, taking the supernatant to be tested, and measuring the absorbance value by the same standard curve method to obtain the specific protein content. The kit is used for detecting superoxide dismutase (SOD) and Malondialdehyde (MDA) kits.

Results of the experiment

The effect of carbon black on food intake, water intake, body weight and liver factor in the heavy metal exposed mice is shown in fig. 1.

After the heavy metal water is exposed, the normal physiological indexes and the growth and development of the mice can be obviously influenced, and the bamboo leaf carbon black added as an adsorbent can improve partial influence brought by the heavy metal water, so that the physiological indexes of the mice are changed to normal trend. Figure 1a shows that in the early part of the experiment, the exposed group was generally lower than the unexposed group, after which the groups gradually converged. In the graph of fig. 1b, the food intake of the mice exposed to heavy metal at the later stage is increased by 65% compared with that of the control group, but the food intake tends to be normal after the protection of the bamboo leaf carbon black, which indicates that the bamboo leaf carbon black can effectively relieve the appetite increase caused by Cd. As is evident from fig. 1c, heavy metals inhibit normal growth and development of mice. After the bamboo leaf carbon black is added, the weight is obviously increased, and the growth condition tends to be normal level and is close to that of a control group.

The liver coefficients of the blank control group in the first and second weeks were 3.82% and 3.62%, and the liver coefficients of the heavy metal exposure group were 5.2% and 4.9%. The liver coefficient of the heavy metal group was significantly increased compared to the control group (P<0.05), and the longer the heavy metal infection time is, the more obvious the hepatomegaly is. The bamboo leaf carbon black can adsorb heavy metal in vivo, so as to slow down hepatomegaly and reduce liver coefficient by about 5%. From the liver coefficient diagram, it can be seen that the bamboo leaf carbon black has a certain adsorption effect on heavy metals, and the influence of the heavy metals on the organism is slowed down.

The effect of carbon black of bamboo leaves on the content of heavy metal in liver and kidney tissues, the result is shown in fig. 2, wherein fig. 2 (a) shows the effect of carbon black of bamboo leaves on the content of heavy metal Cd in liver, and fig. 2 (b) shows the effect of carbon black of bamboo leaves on the content of heavy metal Cd in kidney.

Heavy metals accumulate in the liver and kidney, and for heavy metal Cd, the accumulation in the body is more often the longer the heavy metal Cd is. And the bamboo leaf carbon black can adsorb heavy metals, so that the accumulation of the heavy metals in the body is reduced. With the increase of the carbon black content of the bamboo leaves, the adsorption capacity of the heavy metals is increased, 25% of the heavy metals in the liver are reduced, and 33% of the heavy metals in the kidney are reduced. Therefore, the bamboo leaf carbon black can adsorb heavy metals in vivo, improve the abnormal influence of the heavy metals on the organism and reduce the accumulation of the heavy metals in vivo.

The effect of the bamboo leaf carbon black on the oxidative stress of heavy metals is shown in fig. 3, wherein fig. 3 (a) shows the effect of the bamboo leaf carbon black on the content of liver superoxide dismutase SOD, and fig. 3 (b) shows the effect of the bamboo leaf carbon black on the content of malondialdehyde MDA.

When excessive free radicals are produced, oxidative damage can lead to tissue destruction, leading to increased MDA content in the tissue, affecting the body's antioxidant defense mechanism. The experimental result shows that the content of MDA in the bamboo leaf carbon black treatment group is obviously reduced and tends to a normal group; the SOD content in the first week is close to that in the normal group, the SOD content in the second week is increased along with the increase of the concentration of bamboo leaf carbon Black (BCP) in the liver, compared with the control group, the SOD level is 7.5ppm, and no obvious difference is shown between the groups of 15ppm and 30ppm, the result can be attributed to the adsorption of the bamboo leaf carbon black to heavy metal, and the oxidative damage to the tissues is reduced

Animal experiments with different types of carbon black exposure

The change in food intake, water intake and body weight of the mice is shown in FIG. 4.

As can be seen from the food intake and water intake, there may be some change in the living environment of the mice, and fig. 4c shows that the weight gain of the blank control group for 30 days is 5.96g, the growth of the bamboo leaf carbon black and the activated carbon group is slower than that of the control group, and the influence of the bamboo leaf carbon black on the weight of the mice is smaller than that of the activated carbon.

The effect of different types of carbon black on oxidative stress, the results are shown in FIG. 5,

the SOD content in FIG. 5a shows that the difference between the different groups is very small at 5% (R) ((R))P>0.05) or so. This indicates that the bamboo leaf carbon black or activated carbon has no obvious stimulation to the oxidative stress of the organism and does not cause the abnormal oxidative stress of the organism. FIG. 5b shows that the difference in the malondialdehyde content is significant, and that the MDA content in the normal group is 0.32 nmol-mgprot（P>0.05), the content of malondialdehyde in the activated carbon group is obviously higher and is 2.406 times of that in the normal group. The results show that abnormal oxidative stress reaction exists in the mice of the activated carbon group, malondialdehyde is generated, the body is damaged, and for the bamboo leaf carbon black, the content of the bamboo leaf carbon black is similar to that of the normal group, obvious toxicological effects do not exist, and abnormal oxidative stress conditions cannot be caused.

The effect of different carbon blacks on liver function indices, results are shown in FIG. 6.

ALT, AST and AKP in fig. 6 were all within normal ranges. The AST/ALT values of the bamboo leaf carbon black group and the control group are less than 1, which indicates that the body is healthy and has no liver injury. AST/ALT values of the activated carbon group and the control group are more than 1 and less than 2, which indicates that liver cells are damaged at the moment and the body is possibly in a chronic inflammation state. The normal group AKP content is 21.6U/L, while the bamboo leaf carbon black group AKP content deviation is 12.3%, which is in the normal range, but the active carbon group AKP content is obviously higher by 25%. After the high-concentration activated carbon enters the body, the body may be damaged. When the liver is damaged or obstructed, the blood enters the liver via the lymphatic channel and the liver sinus, and simultaneously, the blood backflow is caused to cause the obvious increase of serum AKP due to the bile excretion obstruction of the liver and the biliary tract. In conclusion, the bamboo leaf carbon black group has no obvious pathogenic expression, and has certain safety as a food additive.

The effect of different carbon blacks on toxicological indices is shown in FIG. 7.

Lactate Dehydrogenase (LDH) is present in almost all tissues, with heart, kidney and skeletal muscle being most abundant, followed by liver, pancreas, spleen, brain, lung, etc. From fig. 7a, the LDH content of each group was almost the same as that of the control group, and the variation was within 3%, and was not significantly changed. When cells are damaged, LDH is produced, increasing its content. In the test, the content of each group is in a normal range, and no obvious liver injury is shown.

Lipid Peroxides (LPO) are products of the reaction of polyunsaturated fatty acids with oxygen radicals, and in normal cases the content of LPO is often very low, but in pathological cases the lipid peroxidation is enhanced, which can lead to an increase in LPO. The increased LPO can cause various damages to the structure and function of cells and cell membranes. In fig. 7b, the bamboo leaf carbon black group is lower than the blank control group, indicating the safety of bamboo leaf carbon black as a food additive. The active carbon group is obviously higher than the control group, which indicates that the active carbon group can damage the organism and cause the structural function change of cells and cell membranes. Bamboo leaf carbon black has a protective effect on the body when added to food, and may be damaged by using activated carbon.

Claims

1. The animal feed additive with biological activity and heavy metal removal is characterized by being prepared from the following raw materials in parts by weight: 20-40 parts of bamboo leaf carbon black, 5-15 parts of white peony root extract concentrated solution, 8-10 parts of bamboo leaf extract concentrated solution, 10-60 parts of chamomile extract concentrated solution, 10-20 parts of folium isatidis extract concentrated solution and 10-30 parts of sodium starch octenyl succinate.

2. The animal feed additive with bioactivity and heavy metal removal function as claimed in claim 1, wherein the bamboo leaf carbon black is prepared by drying, high-temperature carbonization and activation of bamboo, and the microstructure is in the shape of pores with the particle size of 300-.

3. The bioactive and heavy metal-removing animal feed additive as claimed in claim 1, wherein the chamomile extract concentrate is prepared from chamomile, chrysanthemum morifolium and blood chrysanthemum.

4. The bioactive and heavy metal-removing animal feed additive according to claim 1, wherein the additive is used in an amount of 1-15% of the total amount of the animal feed.

5. The method for preparing a bioactive and heavy metal-removing animal feed additive according to claim 1, comprising the steps of:

6. The method for preparing an animal feed additive with biological activity and heavy metal removal as claimed in claim 5, wherein the rotation speed of the magnetic stirring in step 1) is 500-1000 rpm.

7. The method for preparing the animal feed additive with bioactivity and heavy metal removal as claimed in claim 5, wherein the ultrasonic power in step 2) is 400-800W, the high-pressure homogenization condition is 0.1-80 MPa, and the homogenization time is 2-10 min.