Streptomyces miuraensis and soil conditioner and use thereof
By screening Streptomyces micrantha GX2024L6 and its fermentation broth, a soil conditioner that can improve acidic soil was prepared, which solved the problems of soil compaction and nutrient imbalance caused by traditional lime-based amendments, and improved soil pH and fertility, promoting plant growth and soil self-repair.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- GUANGXI UNIV FOR NATITIES
- Filing Date
- 2026-03-04
- Publication Date
- 2026-05-29
Smart Images
Figure CN122104512A_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of microbial technology, specifically relating to a strain of Streptomyces micranthae and its soil conditioner and uses. Background Technology
[0002] With the rapid advancement of industrialization and agricultural modernization, soil acidification has become an increasingly prominent problem globally. In recent years, the soil pH in red soil regions of southern my country (such as Guangxi) has been generally at a weakly acidic or even strongly acidic level due to long-term acid deposition, excessive application of chemical fertilizers, and leaching. This has led to a series of problems, including aluminum toxicity release, increased nutrient loss, and a significant decline in microbial activity, which seriously restricts crop yield improvement and quality enhancement.
[0003] Soil acidification not only directly inhibits plant growth and reduces soil fertility, but also damages the health and stability of the soil ecosystem. Soil microorganisms, as a core component of the soil ecosystem, are deeply involved in the decomposition of soil organic matter, nutrient cycling and transformation, and the formation of soil structure; however, an acidic environment significantly inhibits microbial diversity and activity, leading to the degradation of soil ecological functions. While traditional lime-based amendments (such as CaCO3) can quickly raise soil pH, they easily cause soil compaction and calcium-magnesium nutrient imbalance, and their effect on activating soil nutrients is limited, making it difficult to fundamentally solve the problem of soil acidification, which continues to worsen.
[0004] Compared to traditional chemical soil conditioners, microbial soil conditioners are environmentally friendly, do not cause secondary soil pollution, and enhance soil self-repair capabilities by promoting the decomposition of soil organic matter and nutrient cycling, thus exhibiting long-term sustainable improvement effects. Furthermore, these agents can not only regulate soil pH but also optimize soil structure, improve soil fertility, and enhance plant resistance (such as disease resistance). Therefore, screening and developing functional microorganisms suitable for acidic soils is of great significance for improving acidified soils and maintaining soil ecological health.
[0005] The information disclosed in this background section is intended only to enhance the understanding of the overall background of the invention and should not be construed as an admission or in any way implying that the information constitutes prior art known to those skilled in the art. Summary of the Invention
[0006] The purpose of this invention is to provide a strain of Streptomyces micranthae, its soil conditioner, and its uses.
[0007] To achieve the above objectives, the present invention provides the following technical solution: A strain GX2024L6, whose taxonomic name is *Streptomyces micranthum* (… streptomyces misionensisIt was deposited on December 4, 2024 at the China General Microbiological Culture Collection Center, accession number CGMCC No. 32903.
[0008] The present invention also provides a soil conditioner, wherein the effective component of the soil conditioner is the strain GX2024L6 or the fermentation broth of the strain GX2024L6.
[0009] The present invention also provides the application of the strain GX2024L6 or the soil conditioner in the remediation of acidic soil.
[0010] The present invention also provides the use of the strain GX2024L6 or the soil conditioner in improving the pH value of acidic soil, reducing the total amount of exchangeable acid in soil, and increasing the organic matter content of soil.
[0011] The present invention also provides the use of the strain GX2024L6 or the soil conditioner in improving soil fertility and promoting plant growth.
[0012] More specifically, the preparation method of the fermentation broth of strain GX2024L6 is as follows: strain GX2024L6 is transferred to liquid seed culture medium and cultured by shaking to obtain seed liquid; the seed liquid is inoculated into fermentation medium, fermented at constant temperature, and the fermentation broth is collected, which is the fermentation broth of strain GX2024L6.
[0013] More specifically, the liquid seed culture medium formula is as follows: yeast extract 4-6 g / L, tryptone 9-11 g / L, NaCl 9-11 g / L, pH 5.0-6.0. More specifically, the seed culture conditions are: 37℃, 180rpm shaking culture for 24h.
[0014] More specifically, the fermentation medium formula is as follows: yeast extract 4-6 g / L, tryptone 9-11 g / L, KNO3 0.9-1.1 g / L, NaCl 9-11 g / L, MgSO4 0.4-0.6 g / L, K2PO4 0.4-0.6 g / L and FeSO4 0.01-0.05 g / L, pH value 5.0-6.0.
[0015] More specifically, the seed solution was inoculated at a volume ratio of 7%.
[0016] More specifically, the fermentation culture conditions are: constant temperature fermentation at 37℃ for 72 hours.
[0017] Compared with the prior art, the present invention has the following beneficial effects: This invention screened and obtained a strain GX2024L6, which was identified as *Streptomyces micranthum* by morphological analysis, physiological and biochemical analysis, and molecular biological identification. streptomyces misionensis Experiments have shown that the fermentation broth of strain GX2024L6 has significant effects on improving the pH of acidic soils and enhancing soil fertility. This conditioning effect helps create a more suitable soil environment for plant growth and improves the soil's ability to retain fertilizer and water, which can support the industrial application of soil conditioning agents. Attached Figure Description
[0018] Figure 1 Morphological diagram of strain GX2024L6; Figure 2 The effect of different culture times on alkali production during fermentation of strain GX2024L6; Figure 3 The effect of different fermentation temperatures on alkali production during fermentation of strain GX2024L6; Figure 4 The effect of different inoculum amounts on alkali production during fermentation of strain GX2024L6; Figure 5 The effect of different pH values on alkali production during fermentation of strain GX2024L6. Detailed Implementation
[0019] The technical solution of this invention patent will be clearly and completely described below. Obviously, the described embodiments are only some, not all, of the embodiments of this invention. Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without inventive effort are within the scope of protection of this invention.
[0020] 1. Strain screening 1.1 Screening Culture Media Initial screening culture medium: yeast extract 5 g / L, tryptone 10 g / L, NaCl 10 g / L, MgSO4 0.5 g / L, K2HPO4 0.5 g / L, FeSO4 0.5 g / L, agar powder 20 g / L, pH 5.5, sterilized at 121℃ for 20 min. When the temperature drops to 50-60℃, add 20 ml / L of filtered and sterilized phenolphthalein stock solution (phenolphthalein: alcohol ratio 1:100).
[0021] Secondary screening medium: yeast extract 5 g / L, tryptone 10 g / L, NaCl 10 g / L, MgSO4 0.5 g / L, K2HPO4 0.5 g / L, FeSO4 0.5 g / L, pH 5.5, sterilized at 121℃ for 20 min. After cooling to room temperature, add 20 ml / L of filtered and sterilized phenolphthalein stock solution (phenolphthalein: alcohol ratio 1:100).
[0022] 1.2 Initial screening Place 5g of soil sample into a sterile Erlenmeyer flask, add 50mL of sterile water, gently shake at room temperature for 30 minutes, allow to settle, and take the supernatant and dilute it with sterile water 10. 3 -10 8 The sample was coated onto the primary screening medium and incubated upside down at 37°C.
[0023] 1.3 Secondary screening Colonies with red bacterial rings around the periphery were selected from the primary screening medium and transferred to the secondary screening medium. After incubation at 37°C and 180 rpm for 48 hours with shaking, the pH value of the medium was measured.
[0024] As a result, a strain capable of raising the pH of the culture medium was obtained, which was designated GX2024L6.
[0025] 2. Identification of strain GX2024L6 2.1 Morphological identification The results are as follows Figure 1 As shown.
[0026] Depend on Figure 1 It can be seen that the colonies of strain GX2024L6 are opaque, white, raised, with rounded edges, and covered with white velvety material.
[0027] 2.2 Physiological and Biochemical Identification Physiological and biochemical identification of strain GX2024L6 was performed according to the "Handbook for Systematic Identification of Common Bacteria", and the results are shown in Table 1.
[0028] Table 1. Physiological and biochemical characteristics of strain GX2024L6 Physiological and biochemical experiments L6 Phosphate solubilization ＋ Potassium solubilization ＋ Nitrogen fixation ＋ Starch Degradation ＋ Utilization of phenol red urea ＋ Sodium carboxymethyl cellulose utilization ＋ Milk coagulation and peptone ＋ Sugar fermentation + Maltose fermentation + Glucose fermentation ＋ vp test ＋ Methyl red test _ <![CDATA[6% H2O2]]> _ citrate _ As shown in Table 1, strain GX2024L6 can decompose and utilize glucose, sucrose, and maltose, produce protease, hydrolyze starch, and has the functions of phosphorus solubilization, potassium solubilization, nitrogen fixation, cellulose decomposition, and urea utilization; the methyl red test, 6% H2O2 test, and citrate test were negative.
[0029] 2.3 Molecular biological identification The 16S rDNA sequence of strain GX2024L6 was amplified by PCR (listed as SEQ ID NO.1), and homology analysis was performed on NCBI. The results showed that the 16S rDNA sequence of strain GX2024L6 was similar to... streptomyces misionensis The similarity is 100%.
[0030] In summary, based on morphological analysis, physiological and biochemical identification results, strain GX2024L6 was identified as *Streptomyces mishustinus*. streptomyces misionensis .
[0031] 3. Effects of different culture conditions on alkali production during fermentation of strain GX2024L6 The strain GX2024L6 was transferred to seed culture medium (same as 4.1) and cultured at 37℃ and 180 rpm for 24 h with shaking to obtain seed liquid. The seed liquid was then inoculated into fermentation medium (same as 4.1) at a certain volume ratio and fermented at a constant temperature. The fermentation broth was collected, which is the fermentation broth of strain GX2024L6. This section investigated the effects of different fermentation conditions on alkali production by strain GX2024L6, setting four factors: temperature, inoculum size, pH value, and culture time.
[0032] 3.1 Effect of different culture times on alkali production during fermentation of strain GX2024L6 Temperature 37℃, inoculum size 1%, pH 5.0. Results are shown below. Figure 2 .
[0033] Figure 2 A represents the OD at different fermentation times. 600 The change in the OD value reflects the growth status of strain GX2024L6. On day 3, the OD value was... 600 The value reached its highest, indicating that strain GX2024L6 had reached its optimal growth state. Figure 2 B represents the change in pH value at different fermentation times. As time increases, the pH value continuously rises. Figure 2 A, Although the pH value continued to rise after day 4, the OD 600 The value is decreasing, indicating that strain GX2024L6 has entered the death phase and cell lysis has led to an increase in the pH of the fermentation broth. Therefore, the optimal fermentation time is 3 days.
[0034] 3.2 Effect of different fermentation temperatures on alkali production during fermentation of strain GX2024L6 Inoculum size 1%, pH 5.0, culture time 72 h. Results are shown below. Figure 3 .
[0035] Figure 3 A represents the growth status of strain GX2024L6 at different fermentation temperatures, with OD at 37℃. 600 The highest value indicates that strain GX2024L6 grows optimally, and the fermentation temperature is preferably 37℃. Figure 3 B represents the pH value of the fermentation broth at different fermentation temperatures. The pH value is 7.85 at 28℃, 7.86 at 31℃, 8.25 at 34℃, 8.35 at 37℃, and 8.38 at 40℃. Based on the analysis of Figure 3A, the pH values of the fermentation broth at 37℃ and 40℃ are similar, but the bacterial growth is better at 37℃. Therefore, the optimal fermentation temperature is 37℃.
[0036] 3.4 Effect of different inoculum sizes on alkali production during fermentation of strain GX2024L6 Temperature 37℃, pH 5.0, incubation time 72h. Results are shown below. Figure 4 .
[0037] Figure 4 A represents the OD at different inoculation amounts. 600 The change in the value reflects the growth status of strain GX2024L6. The growth status of strain GX2024L6 is optimal when the inoculum amount is 7%. Figure 4 B represents the pH change at different inoculum amounts; the pH reaches its highest value of 8.73 at an inoculum amount of 7%. (Combined with...) Figure 4 A and Figure 4 B indicates that the optimal inoculation dose is 7%.
[0038] 3.5 Effect of different pH values on alkali production during fermentation of strain GX2024L6 Temperature 37℃, inoculum size 7%, incubation time 72h. Results are shown below. Figure 5 .
[0039] Figure 5 A represents the effect of different initial pH values on the OD values of fermentation broth from strain GX2024L6. 600 The effect of pH value, which reflects the growth status of strain GX2024L6, is that the OD value at an initial pH of 5 is... 600 The value is the highest, indicating that the strain is growing optimally at this point. Figure 5 B represents the effect of different initial pH values on the pH value of the fermentation broth. When the initial pH values are 5, 6, 7, 8, and 9, the corresponding pH values of the fermentation broth are 9.28, 9.13, 9.28, and 9.36, respectively. The results show that the values are not significantly different. Figure 5 Analysis A indicates that the optimal fermentation pH is 5.
[0040] 4. Fermentation broth of strain GX2024L6 4.1 Culture medium Seed culture medium: yeast extract 5 g / L, tryptone 10 g / L, NaCl 10 g / L, pH 5.0 Fermentation medium: yeast extract 5 g / L, tryptone 10 g / L, NaCl 10 g / L, MgSO4 0.5 g / L, K2HPO4 0.5 g / L, FeSO4 0.5 g / L, pH 5.5.
[0041] 4.2 Fermentation Culture A single colony of strain GX2024L6 was picked and transferred to 50 mL of seed culture medium and cultured at 37 °C and 180 rpm for 24 h to obtain seed liquid. The seed liquid was then inoculated into fermentation medium at a volume ratio of 7% and fermented at 37 °C for 72 h. The fermentation broth was collected, which is the fermentation broth of strain GX2024L6.
[0042] 4.3 Conditioning effect of fermentation broth on acidic soil The fermentation broth of strain GX2024L6 was inoculated into 1 kg of acidic soil at a volume ratio of 5% (referred to as the treatment group), with an uninoculated blank control. The soil was placed indoors at 25℃ with a relative soil moisture content of about 20%, and the changes in soil physicochemical properties were measured for 30 days. The results are shown in Table 2.
[0043] Table 2. Effects of fermentation broth from strain GX2024L6 on soil physicochemical properties. Testing items 0d 30 days (treatment group) 30d (blank group) pH 4.7 6.2 5.1 Organic matter (%) 27.78 48.24 29.55 Total nitrogen (mg / kg) 28 98 44 Total phosphorus (mg / kg) 96 177 150 Total potassium (mg / kg) 98 325 169 Ammonium nitrogen (mg / kg) 21.42 69.76 10.91 Available phosphorus (mg / kg) 89.97 148.8 144.8 Available potassium (mg / kg) 74.1 203.5 108.3 Total exchangeable acidity in soil (cmol / kg) 3.8 1.4 3.6 <![CDATA[Soil exchangeable H + (cmol / kg)]]> 2 0.7 2 <![CDATA[Soil exchangeable Al 3+ (cmol / kg)]]> 1.8 0.7 1.6 Electrical conductivity (µs / cm) 218 412 220 Table 2 shows that the fermentation broth of strain GX2024L6 can increase soil pH, organic matter content, and soil nutrient content. Additionally, it can increase the total exchangeable acidity and exchangeable hydrogen content of the soil. + Exchangeable Al3 with soil + The electrical conductivity decreased, but the conductivity increased.
[0044] In conclusion, the fermentation broth of strain GX2024L6 demonstrated significant effects in improving the pH of acidic soils, enhancing soil fertility, and improving soil chemical properties. This conditioning effect helps create a more suitable soil environment for plant growth, improves the soil's ability to retain fertilizer and water, and promotes the growth and development of plant roots, demonstrating the potential for industrial application of soil conditioning microbial agents.
[0045] The foregoing description of specific exemplary embodiments of the invention is for illustrative and explanatory purposes. These descriptions are not intended to limit the invention to the precise forms disclosed, and it will be apparent that many changes and variations can be made in accordance with the foregoing teachings. The exemplary embodiments were chosen and described in order to explain the specific principles of the invention and its practical application, thereby enabling those skilled in the art to implement and utilize various different exemplary embodiments of the invention, as well as various different choices and variations. The scope of the invention is intended to be defined by the claims and their equivalents.
Claims
1. A strain GX2024L6, characterized in that, The strain GX2024L6 is taxonomically named *Streptomyces micseudomonas*. streptomyces misionensis It was deposited on December 4, 2024 at the China General Microbiological Culture Collection Center, accession number CGMCC No. 32903.
2. A soil conditioner, characterized in that, The effective component of the soil conditioner is the strain GX2024L6 described in claim 1 or its fermentation broth.
3. The application of the strain GX2024L6 of claim 1 or the soil conditioner of claim 2 in the remediation of acidic soil.
4. The use of the strain GX2024L6 of claim 1 or the soil conditioner of claim 2 in improving the pH value of acidic soil, reducing the total amount of exchangeable acid in soil, and increasing the content of organic matter in soil.
5. The use of the strain GX2024L6 of claim 1 or the soil conditioner of claim 2 in improving soil fertility and promoting plant growth.
6. The soil conditioner according to claim 2, characterized in that, The preparation method of the fermentation broth of strain GX2024L6 is as follows: strain GX2024L6 is transferred to liquid seed culture medium and cultured by shaking to obtain seed liquid; The seed culture was inoculated into the fermentation medium, fermented at a constant temperature, and the fermentation broth was collected, which is the fermentation broth of strain GX2024L6.
7. The soil conditioner according to claim 5, characterized in that, The liquid seed culture medium formula is as follows: yeast extract 4-6 g / L, tryptone 9-11 g / L, NaCl 9-11 g / L, pH 5.0-6.0; the seed culture conditions are: 37℃, shaking culture at 180 rpm for 24 h.
8. The soil conditioner according to claim 5, characterized in that, The fermentation medium is formulated as follows: yeast extract 4-6 g / L, tryptone 9-11 g / L, KNO3 0.9-1.1 g / L, NaCl 9-11 g / L, MgSO4 0.4-0.6 g / L, K2PO4 0.4-0.6 g / L and FeSO4 0.01-0.05 g / L, with a pH of 5.0-6.
0.
9. The soil conditioner according to claim 5, characterized in that, The seed solution was inoculated at a volume ratio of 7%.
10. The soil conditioner according to claim 5, characterized in that, The fermentation conditions were: constant temperature fermentation at 37℃ for 72 hours.