Application of radix asparagi in improving quality of corn silage

Abstract

The invention provides application of radix asparagi in improving the quality of corn silage. According to the application, the radix asparagi is added into the corn silage, so that the fermentation quality, the oxidation resistance and the nutritional quality of the corn silage can be improved, the proliferation of lactic acid bacteria in the corn silage is promoted, and meanwhile, the abundance of infectious microbes is inhibited.

Description

Field of the invention:

[0001] The present invention relates to the field of silage, and in particular to the application of Asparagus cochinchinensis in improving the quality of corn silage. Background technology:

[0002] Corn (Zea mays L.) is an annual tall herbaceous plant of the genus Zea of ​​the family Gramineae. It is one of the three major staple foods of the Chinese people and is widely grown in China. At the same time, because corn plants are rich in nutrients such as protein, soluble sugars and vitamins, they are also used as a source of high-quality animal feed. Mixing corn with wheat bran, honeysuckle, etc. for silage can significantly increase the success rate of corn silage and improve the nutritional value of silage.

[0003] In breeding production, livestock and poultry are often affected by oxidative stress, which causes problems such as decreased immunity and enteritis. At present, exogenous antibiotics are often added for prevention and treatment in production, but this method will cause drugs to remain in the animal body. Herbs rich in bioactive substances such as polysaccharides and saponins are natural and highly effective exogenous antioxidants. Asparagus cochinchinensis (Lour.) Merr. belongs to the genus Asparagus of the Asparagaceae family. It is a perennial climbing herb with slightly fleshy spindle-shaped tubers, and the twigs are nearly leaf-shaped, often in clusters. The above-ground part of Asparagus is often discarded and not effectively utilized. Its tuber is a commonly used Chinese medicine "Asparagus" with medicinal and edible homology, which has the effects of nourishing yin and moistening dryness, clearing heat and relieving cough. Asparagus contains a certain amount of saponins, polysaccharides and polyphenols, all of which have health and medicinal value, are beneficial to animal health, and can improve the oxidative stress problem of livestock and poultry. Therefore, it is necessary to further develop Asparagus. At present, there is no relevant research on the use of Asparagus for silage. Summary of the invention:

[0004] In order to increase the health function of corn silage to livestock and improve the utilization value of asparagus plants, the present invention mixes the above-ground parts and tubers of asparagus with corn for silage, thereby improving the fermentation quality, nutritional quality and antioxidant capacity of silage, giving corn silage the dual characteristics of nutrition and health functions, and also providing a new direction for the use of asparagus.

[0005] On the one hand, the present application provides the use of Asparagus cochinchinensis in improving the quality of corn silage.

[0006] Furthermore, the asparagus is one or more of asparagus leaf-like branches, asparagus aerial parts, asparagus underground parts, and asparagus tubers.

[0007] Furthermore, the corn is the remaining above-ground part after harvesting corn.

[0008] Furthermore, in the application, 60-80% by weight of corn and 20-40% by weight of asparagus are mixed to obtain a mixed raw material, and lactic acid bacteria are added to the mixed raw material before ensiling.

[0009] Furthermore, in the application, 10 weight % of aerial parts of Asparagus cochinchinensis, 10 weight % of tubers of Asparagus cochinchinensis and 80 weight % of corn are mixed; or 20 weight % of branches and leaves of Asparagus cochinchinensis, 20 weight % of tubers of Asparagus cochinchinensis and 60 weight % of corn are mixed.

[0010] Furthermore, in the application, the moisture content of the mixed raw materials is adjusted to 50-70% by weight, preferably 60% by weight.

[0011] Furthermore, the number of viable lactic acid bacteria was 1.0×10 10 cfu / g-1.0×10 12 cfu / g; the amount of lactic acid bacteria added is 1-2g / ton of mixed raw materials.

[0012] Furthermore, the number of viable lactic acid bacteria was 1.0×10 11 cfu / g; the amount of lactic acid bacteria added is 1g / ton of mixed raw materials.

[0013] Furthermore, the ensiling time is 30-60 days.

[0014] Furthermore, the ensiling time is 40-50 days.

[0015] Further, the improvement of corn silage quality is one or more of the following (a)-(d):

[0016] (a) Improve the fermentation quality of corn silage;

[0017] (b) improving the antioxidant capacity of corn silage;

[0018] (c) Improve the nutritional quality of corn silage;

[0019] (d) Promote the proliferation of lactic acid bacteria in corn silage and reduce the abundance of harmful bacteria.

[0020] On the other hand, the present application provides corn silage obtained using the above application.

[0021] Beneficial effects:

[0022] (1) In the present invention, asparagus is added to corn silage to improve the fermentation quality of silage, including reducing the ammonia nitrogen content and reducing the pH of the fermentation product; improve the nutritional quality of silage, including increasing the soluble sugar content and reducing the neutral detergent fiber and acid detergent fiber content; improve the antioxidant capacity of silage,

[0023] (2) The present invention uses Asparagus cochinchinensis in corn silage, and the antioxidant and antibacterial properties of Asparagus cochinchinensis may inhibit undesirable microorganisms in the lactic acid fermentation process and improve the antioxidant capacity of silage.

[0024] (3) The asparagus and corn mixed silage of the present invention can provide high-quality functional feed with "health care" for animal husbandry. Description of the drawings:

[0025] Figure 1 Relative abundance of microorganisms at the genus level after asparagus and corn were ensiled for 45 days. Specific implementation method:

[0026] The composite lactic acid bacteria used are: Lactobacillus plantarum and Lactobacillus buchneri (Shaanxi Baichuan Biotechnology Co., Ltd., nominally derived from CGMCC No.1.12732 and CGMCC No.1.3114), mixed in a one-to-one ratio of viable bacteria count.

[0027] Example 1 Effect of Asparagus cochinchinensis on the fermentation quality of corn silage

[0028] Experimental treatment and grouping:

[0029] 100% corn plants (CK); 10% Asparagus aerial parts, 10% Asparagus tubers and 80% corn plants (M1); 20% Asparagus branches and leaves, 20% Asparagus tubers and 60% corn plants (M2); the above proportions are calculated by weight (drying). Fixed addition of 1g / t of the composite lactic acid bacteria agent, there are 3 treatment groups in total, each with 3 replicates.

[0030] After harvesting corn, the remaining above-ground part of the corn plant is harvested, and the corn plant is cut into 1-2 cm with a mower. After adding different proportions of crushed asparagus, it is fully mixed again, and the water content is adjusted to about 60%. Then it is put into a polyethylene vacuum silage bag, and after vacuuming, it is placed in a constant temperature box at 28°C and stored away from light. Each silage bag contains about 200g of silage. After 45 days of silage, the bag is opened and sampled for analysis of various indicators.

[0031] Using the quartering method, 10 g of fresh silage was taken for each repetition and put into a 250 mL conical flask, 90 mL of deionized water was added, and the silage was placed in a 2-8 ° C refrigerator for 24 hours and then filtered with filter paper to obtain the silage extract for the determination of pH value, lactic acid, acetic acid, propionic acid, butyric acid, and ammonia nitrogen. Each indicator was repeated 3 times.

[0032] The pH value was determined using a PHS-3C pH meter from Supo, and the measurement was repeated three times for each sample. The contents of lactic acid, acetic acid, propionic acid, and butyric acid were determined using a Shimadzu high performance liquid chromatograph (chromatographic column: Agilent TC C18 column (250 mm × 4.6 mm × 5 μm), injection 20 μL, flow rate 1.0 mL min 1 , column temperature 30 °C, UV detection wavelength 214 nm, running time 45 min, mobile phase A: methanol, mobile phase B: 0.02 mol·L 1 Potassium dihydrogen phosphate aqueous solution (adjusted to pH 2.70 with phosphoric acid) was eluted in an isocratic (A:B=3:97) manner; ammonia nitrogen was determined using the phenol-sodium hypochlorite method. The dry matter (DM) content was determined by oven drying to constant weight.

[0033] The test results are shown in Table 1:

[0034] Table 1. Effect of Asparagus cochinchinensis on the fermentation quality of corn silage

[0035]

[0036] Note: FM: fresh weight; NA: not detected

[0037] pH value is one of the important indicators to measure the quality of silage. It is generally believed that a rapid decrease in pH and a lower pH are conducive to maintaining protein nitrogen sources. At the same time, the ammonia nitrogen results also show that protein decomposition is reduced after the addition of asparagus. The accumulation of lactic acid and acetic acid content is conducive to inhibiting the reproduction of harmful microorganisms, while the appearance of propionic acid and butyric acid indicates that the fermentation quality has declined and affects the utilization of protein by livestock. As shown in Table 1, after 45 days of mixed silage of asparagus and corn, the pH, propionic acid and ammonia nitrogen content of the treatment group decreased, while the dry matter, lactic acid and acetic acid content of the treatment group increased.

[0038] The above results show that the fermentation quality of corn silage can be significantly improved by adding Asparagus cochinchinensis.

[0039] Example 2 Effect of Asparagus cochinchinensis on the nutritional quality of corn silage

[0040] Experimental treatment and grouping: same as Example 1.

[0041] 100g of sample was taken by quartering method, dried at 65℃, and the dry sample after crushing and sieving was used to determine soluble sugar, crude protein, neutral detergent fiber and acid detergent fiber, and each index was repeated 3 times. The soluble sugar content was determined by anthrone-concentrated sulfuric acid colorimetry; crude protein (CP) was determined using a fully automatic Kjeldahl nitrogen analyzer (Buch, Switzerland, K-370); neutral detergent fiber (NDF) and acid detergent fiber (ADF) were determined using the Van Soest detergent fiber analysis method.

[0042] The test results are shown in Table 2:

[0043] Table 2 Effect of Asparagus cochinchinensis on nutritional quality of corn silage

[0044]

[0045] Note: DM: dry matter

[0046] Soluble sugar is an important nutrient in feed. Neutral detergent fiber and acid detergent fiber are also important fiber components in forage, but excessive content of neutral detergent fiber and acid detergent cellulose will reduce the digestibility of livestock.

[0047] As shown in Table 2, after 45 days of mixed silage of asparagus and corn, the soluble sugar content of the treatment group increased significantly, while the neutral detergent fiber and acid detergent fiber contents decreased significantly.

[0048] The above results show that the nutritional quality of corn silage can be significantly improved by adding Asparagus cochinchinensis.

[0049] Example 3 Effect of Asparagus cochinchinensis on the antioxidant capacity of corn silage.

[0050] Experimental group and grouping: the same as in Example 1.

[0051] (1) ABTS cationic free radical scavenging ability

[0052] Establishment of standard curve: A certain amount of 10 mg / mL vitamin C standard stock solution was taken to prepare 25, 10, 5, 2, and 1 mg / mL vitamin C standard working solutions. The total antioxidant capacity (T-AOC) test kit (ABTS microplate method) (purchased from Beijing Regen Biotechnology Co., Ltd.) was operated according to the instructions. The absorbance was measured at a wavelength of 734 nm, and the linear equation was obtained as follows: y=-57.602x+33.469, R 2 =0.9962, indicating that the ABTS cationic radical scavenging ability has a good linear relationship.

[0053] Sample determination: The operation was carried out according to the instructions of the total antioxidant capacity (T-AOC) detection kit (ABTS microplate method) (purchased from Beijing Regen Biotechnology Co., Ltd.). Each sample was determined three times.

[0054] (2) Determination of DPPH free radical scavenging ability

[0055] Establishment of standard curve: A certain amount of 10 mg / mL vitamin C standard stock solution was taken to prepare 25, 10, 5, 2, and 1 mg / mL vitamin C standard working solutions. The operation was carried out according to the instructions of the DPPH free radical scavenging rate detection kit (colorimetric method) (purchased from Beijing Regen Biotechnology Co., Ltd.), and the absorbance was measured at a wavelength of 517 nm. The linear equation was y=-49.04+38.894, R 2 =0.9998, indicating that the DPPH free radical scavenging ability has a good linear relationship

[0056] Sample determination: The operation was carried out according to the instructions of the DPPH free radical scavenging rate detection kit (colorimetric method) (purchased from Beijing Regen Biotechnology Co., Ltd.). Each sample was determined three times.

[0057] (3) FRAP iron ion reduction / oxidation capacity assay

[0058] Establishment of standard curve: A certain amount of 40 μmol / mL FeSO4 standard stock solution was taken to prepare 0.2, 0.1, 0.05, 0.02, and 0.01 μmol / mL FeSO4 standard working solutions. The operation was carried out according to the instructions of the total antioxidant capacity (T-AOC) test kit (purchased from Beijing Solebow Technology Co., Ltd.). The absorbance was measured at a wavelength of 593 nm, and the linear equation was obtained as follows: y=0.1896-0.0064, R 2 =0.996, indicating that the FRAP iron ion reduction / oxidation capacity has a good linear relationship

[0059] Sample determination: The total antioxidant capacity (T-AOC) test kit (purchased from Beijing Solebow Technology Co., Ltd.) was used for the operation. Each sample was determined three times.

[0060] Table 3 Effect of Asparagus cochinchinensis on antioxidant capacity of corn silage

[0061]

[0062] As shown in Table 3, after 45 days of mixed silage of Asparagus and corn, the DPPH free radical scavenging rate and FRAP iron ion reduction / antioxidant capacity of the treatment group were significantly higher than those of the control group, while the ABTS cation free radical scavenging rate did not change significantly.

[0063] The above results showed that the antioxidant capacity of silage was significantly improved after adding Asparagus cochinchinensis.

[0064] Example 4 Effect of Asparagus cochinchinensis on corn silage fermentation microorganisms

[0065] Experimental treatment and grouping: 100% corn plants (CK), 10% Asparagus aerial parts, 10% Asparagus tubers and 80% corn plants (M1). Fixed addition of 1g / t of compound lactic acid bacteria agent, there are 2 treatment groups, each with 3 replicates.

[0066] For each repetition of the quartering method, 20 g of fresh silage was taken, freeze-dried and crushed at -80°C, and passed through a 4 mm sieve. 1 g was taken and ground, and the sample gDNA was purified using a DNA extraction kit (Zymo Research BIOMICS DNA Microprep Kit). DNA quality was tested using 0.8% agarose electrophoresis, and DNA concentration was tested using Tecan F200 (PicoGreen dye method). Primers 515F and 806R (primer sequences: 5'-GTGYCAGCMGCCGCGGTAA-3' and 5'-GGACTACHVGGGTWTCTAAT-3', respectively) were used to amplify the 16S rDNA V4 region of the sample. The PCR program was as follows: pre-denaturation at 94°C for 1 min, denaturation at 94°C for 20 s, annealing at 54°C for 30 s and extension at 72°C for 30 s, 25 cycles, and finally amplification at 72°C for 5 min. PE250 sequencing was used, and the sequencing platform was ILLUMINA. FLASH (version 1.2.1.1) was used to splice double-end sequences. Using sabre, each sample sequence was split from the raw reads based on the Barcode, and the Barcode sequence was truncated. QIIME2 (version 2020.2) was then used for quality control. The Shannon diversity index, Simpson diversity index, and Chao1 diversity index were determined using R software.

[0067] The test results are shown in Table 4 below.

[0068] Table 4 Effect of asparagus supplementation on bacterial diversity in corn silage

[0069]

[0070] As shown in Table 4, after 45 days of co-ensilage of asparagus and corn, the Chao1 index, Shannon index and Simpson index of the M1 bacterial community in the treatment group were significantly lower than those in the control group (CK), indicating that the addition of asparagus significantly reduced the diversity and richness of the bacterial community in corn silage.

[0071] Depend on Figure 1 It can be seen that after 45 days of co-ensilage of asparagus and corn, the proportion of M1 Lactobacillus bacteria in the treatment group was significantly higher than that in the control group.

[0072] The above results show that after adding Asparagus cochinchinensis, beneficial microorganisms lactic acid bacteria multiplied significantly and the growth of harmful bacteria was prevented.

Claims

1. Application of Asparagus cochinchinensis in improving the quality of corn silage.

2. The use according to claim 1, wherein the asparagus is one or more of asparagus leaf-like branches, asparagus aerial parts, asparagus underground parts, and asparagus tuberous roots.

3. The use according to claim 1 or 2, wherein the corn is the remaining above-ground part after harvesting corn.

4. The use according to any one of claims 1 to 3, wherein 60-80% by weight of corn and 20-40% by weight of asparagus are mixed to obtain a mixed raw material, and lactic acid bacteria are added to the mixed raw material before ensiling.

5. The application according to claim 4, wherein 10 wt % of aerial parts of Asparagus cochinchinensis, 10 wt % of tuberous roots of Asparagus cochinchinensis and 80 wt % of corn are mixed to obtain a mixed raw material; or 20 wt % of branches and leaves of Asparagus cochinchinensis, 20 wt % of tuberous roots of Asparagus cochinchinensis and 60 wt % are mixed to obtain a mixed raw material; in the application, the moisture content of the mixed raw material is adjusted to 50-70 wt %, preferably 60 wt %.

6. The use according to claim 4, wherein the viable lactic acid bacteria count is 1.0×10 10 cfu / g-1.0×10 12 cfu / g; the amount of lactic acid bacteria added is 1-2g / ton of mixed raw materials.

7. The use according to claim 5, wherein the viable lactic acid bacteria count is 1.0×10 11 cfu / g; the amount of lactic acid bacteria added is 1g / ton of mixed raw materials.

8. The use according to claim 4, wherein the ensiling time is 30-60 days, preferably, the ensiling time is 40-50 days.

9. The use according to claim 1, wherein the improving the quality of corn silage is one or more of the following (a)-(d): (a) Improve the fermentation quality of corn silage; (b) improving the antioxidant capacity of corn silage; (c) Improve the nutritional quality of corn silage; (d) Promote the proliferation of lactic acid bacteria in corn silage and reduce the abundance of harmful bacteria.

10. Corn silage obtained using the use according to any one of claims 1 to 10.

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