CN111202092A - Method for preparing efficient and stable composite nano-silver bacteriostatic agent by one-step method through lotus root extract - Google Patents
Method for preparing efficient and stable composite nano-silver bacteriostatic agent by one-step method through lotus root extract Download PDFInfo
- Publication number
- CN111202092A CN111202092A CN202010036131.0A CN202010036131A CN111202092A CN 111202092 A CN111202092 A CN 111202092A CN 202010036131 A CN202010036131 A CN 202010036131A CN 111202092 A CN111202092 A CN 111202092A
- Authority
- CN
- China
- Prior art keywords
- lotus root
- silver
- chitosan
- nano
- bacteriostatic agent
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
Images
Classifications
-
- A—HUMAN NECESSITIES
- A01—AGRICULTURE; FORESTRY; ANIMAL HUSBANDRY; HUNTING; TRAPPING; FISHING
- A01N—PRESERVATION OF BODIES OF HUMANS OR ANIMALS OR PLANTS OR PARTS THEREOF; BIOCIDES, e.g. AS DISINFECTANTS, AS PESTICIDES OR AS HERBICIDES; PEST REPELLANTS OR ATTRACTANTS; PLANT GROWTH REGULATORS
- A01N59/00—Biocides, pest repellants or attractants, or plant growth regulators containing elements or inorganic compounds
- A01N59/16—Heavy metals; Compounds thereof
-
- A—HUMAN NECESSITIES
- A01—AGRICULTURE; FORESTRY; ANIMAL HUSBANDRY; HUNTING; TRAPPING; FISHING
- A01N—PRESERVATION OF BODIES OF HUMANS OR ANIMALS OR PLANTS OR PARTS THEREOF; BIOCIDES, e.g. AS DISINFECTANTS, AS PESTICIDES OR AS HERBICIDES; PEST REPELLANTS OR ATTRACTANTS; PLANT GROWTH REGULATORS
- A01N25/00—Biocides, pest repellants or attractants, or plant growth regulators, characterised by their forms, or by their non-active ingredients or by their methods of application, e.g. seed treatment or sequential application; Substances for reducing the noxious effect of the active ingredients to organisms other than pests
- A01N25/08—Biocides, pest repellants or attractants, or plant growth regulators, characterised by their forms, or by their non-active ingredients or by their methods of application, e.g. seed treatment or sequential application; Substances for reducing the noxious effect of the active ingredients to organisms other than pests containing solids as carriers or diluents
- A01N25/10—Macromolecular compounds
-
- A—HUMAN NECESSITIES
- A01—AGRICULTURE; FORESTRY; ANIMAL HUSBANDRY; HUNTING; TRAPPING; FISHING
- A01N—PRESERVATION OF BODIES OF HUMANS OR ANIMALS OR PLANTS OR PARTS THEREOF; BIOCIDES, e.g. AS DISINFECTANTS, AS PESTICIDES OR AS HERBICIDES; PEST REPELLANTS OR ATTRACTANTS; PLANT GROWTH REGULATORS
- A01N25/00—Biocides, pest repellants or attractants, or plant growth regulators, characterised by their forms, or by their non-active ingredients or by their methods of application, e.g. seed treatment or sequential application; Substances for reducing the noxious effect of the active ingredients to organisms other than pests
- A01N25/22—Biocides, pest repellants or attractants, or plant growth regulators, characterised by their forms, or by their non-active ingredients or by their methods of application, e.g. seed treatment or sequential application; Substances for reducing the noxious effect of the active ingredients to organisms other than pests containing ingredients stabilising the active ingredients
-
- A—HUMAN NECESSITIES
- A01—AGRICULTURE; FORESTRY; ANIMAL HUSBANDRY; HUNTING; TRAPPING; FISHING
- A01N—PRESERVATION OF BODIES OF HUMANS OR ANIMALS OR PLANTS OR PARTS THEREOF; BIOCIDES, e.g. AS DISINFECTANTS, AS PESTICIDES OR AS HERBICIDES; PEST REPELLANTS OR ATTRACTANTS; PLANT GROWTH REGULATORS
- A01N43/00—Biocides, pest repellants or attractants, or plant growth regulators containing heterocyclic compounds
- A01N43/02—Biocides, pest repellants or attractants, or plant growth regulators containing heterocyclic compounds having rings with one or more oxygen or sulfur atoms as the only ring hetero atoms
- A01N43/04—Biocides, pest repellants or attractants, or plant growth regulators containing heterocyclic compounds having rings with one or more oxygen or sulfur atoms as the only ring hetero atoms with one hetero atom
- A01N43/14—Biocides, pest repellants or attractants, or plant growth regulators containing heterocyclic compounds having rings with one or more oxygen or sulfur atoms as the only ring hetero atoms with one hetero atom six-membered rings
- A01N43/16—Biocides, pest repellants or attractants, or plant growth regulators containing heterocyclic compounds having rings with one or more oxygen or sulfur atoms as the only ring hetero atoms with one hetero atom six-membered rings with oxygen as the ring hetero atom
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
- B22F9/00—Making metallic powder or suspensions thereof
- B22F9/16—Making metallic powder or suspensions thereof using chemical processes
- B22F9/18—Making metallic powder or suspensions thereof using chemical processes with reduction of metal compounds
- B22F9/24—Making metallic powder or suspensions thereof using chemical processes with reduction of metal compounds starting from liquid metal compounds, e.g. solutions
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B82—NANOTECHNOLOGY
- B82Y—SPECIFIC USES OR APPLICATIONS OF NANOSTRUCTURES; MEASUREMENT OR ANALYSIS OF NANOSTRUCTURES; MANUFACTURE OR TREATMENT OF NANOSTRUCTURES
- B82Y30/00—Nanotechnology for materials or surface science, e.g. nanocomposites
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B82—NANOTECHNOLOGY
- B82Y—SPECIFIC USES OR APPLICATIONS OF NANOSTRUCTURES; MEASUREMENT OR ANALYSIS OF NANOSTRUCTURES; MANUFACTURE OR TREATMENT OF NANOSTRUCTURES
- B82Y40/00—Manufacture or treatment of nanostructures
Landscapes
- Life Sciences & Earth Sciences (AREA)
- Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- General Health & Medical Sciences (AREA)
- Health & Medical Sciences (AREA)
- Wood Science & Technology (AREA)
- Pest Control & Pesticides (AREA)
- Nanotechnology (AREA)
- Environmental Sciences (AREA)
- Zoology (AREA)
- Dentistry (AREA)
- Plant Pathology (AREA)
- Agronomy & Crop Science (AREA)
- Physics & Mathematics (AREA)
- Condensed Matter Physics & Semiconductors (AREA)
- General Physics & Mathematics (AREA)
- Toxicology (AREA)
- Crystallography & Structural Chemistry (AREA)
- Manufacturing & Machinery (AREA)
- Materials Engineering (AREA)
- Composite Materials (AREA)
- Inorganic Chemistry (AREA)
- Chemical Kinetics & Catalysis (AREA)
- General Chemical & Material Sciences (AREA)
- Agricultural Chemicals And Associated Chemicals (AREA)
Abstract
The invention relates to the field of preparation of novel bacteriostatic agents, in particular to a preparation method of a biological-mediated composite nano-silver bacteriostatic agent. The method comprises the following steps: 1) cleaning lotus roots, slicing, and drying to constant weight to obtain dried lotus root slices; 2) crushing and grinding the dried lotus root slices into powder, mixing the powder with an extracting agent according to the mass ratio of 1: 1-100, performing 100-500W microwave treatment for 5-10min, heating, refluxing, centrifuging, taking supernatant, and placing the supernatant at 4 ℃ for later use; 3) weighing 0.1-3g of chitosan, adding the chitosan into 100mL of 1% glacial acid solution, and continuously stirring overnight to completely dissolve the chitosan for later use; 4) and adding the 1-10mL of chitosan solution into 30mL of double distilled water, adding a certain volume of silver nitrate solution, continuously stirring for 5min, then adding 0.1-10mL of lotus root extract, fixing the volume to 50mL, and heating and refluxing to obtain the composite nano-silver bacteriostatic agent. The invention fully exerts the synergistic bacteriostasis of the biological nano-silver and the chitosan, achieves obvious bacteriostasis effect, and the composite biological nano-silver preparation prepared by taking the chitosan as a carrier is more stable.
Description
Technical Field
The invention relates to the field of preparation of novel bacteriostatic agents, in particular to a preparation method of a biological-mediated composite nano-silver bacteriostatic agent.
Background
Nelumbo nucifera Gaertn belongs to Magnoliaceae family and is a perennial aquatic herb. The rhizome of the vegetable can be eaten raw or cooked, and is one of the widely eaten vegetables. Besides eating, the lotus root also has the medicinal values of clearing heat and promoting the production of body fluid, promoting appetite and strengthening spleen, stopping bleeding and removing blood stasis, benefiting blood and tonifying heart, stopping diarrhea, reducing blood pressure, reducing blood sugar and the like. Modern scientific researches find that the lotus root is rich in polyphenols such as catechin, catechol, bisabolol, dopa, rutin, chlorogenic acid, caffeic acid and the like, and also contains organic acid, tannin, polysaccharide, saponin, vitamin C and the like, can effectively remove oxygen free radicals, and has the effects of resisting oxidation and aging. Therefore, the lotus root has strong oxidation resistance and is an excellent raw material for extracting the antioxidant.
The chitosan is a chitin N-deacetylated product, has film forming property, biodegradability, biocompatibility, safety and no toxicity, has rich amino and carboxyl on the surface of the chitosan, and provides a binding site for preparing the composite material. Meanwhile, the chitosan is a natural bacteriostatic agent and has good inhibitory action on bacteria such as escherichia coli, staphylococcus aureus, bacillus subtilis, pseudomonas and the like and fungi such as candida albicans, pellicularia, neurospora and the like. However, the bacteriostatic ability of chitosan is mild, which greatly limits the application of chitosan in antibiosis.
The nano silver is a metal silver simple substance with the particle size of nano level. With the rise of nanotechnology, nano silver becomes a novel bacteriostatic agent with huge specific surface area and small size effect, unique bacteriostatic mechanism and good bacteriostatic performance, and is widely applied to the bacteriostatic fields of chemical engineering, textile, ceramics, life science and medicine. The preparation method of the nano silver mainly comprises three major methods, namely a chemical synthesis method, a physical synthesis method and a biological synthesis method. The physical method and the chemical method have high requirements on synthesis equipment, chemical reagents harmful to the environment are often required to be added in the experimental process, and the synthesized nano silver particles have high surface activity and are easy to agglomerate, so that the antibacterial function is lost, and the long-term storage is not facilitated. Compared with other traditional synthetic methods, the biosynthesis method for preparing the nano silver by using the reducing agent contained in organisms has the advantages of low cost, environmental friendliness, broad-spectrum and high efficiency, can fully utilize biological resources, is easy to amplify, is suitable for large-scale industrial production, and accords with the concepts of low cost, low energy consumption and green and environment-friendly development of modern science and technology. Although there are many reports of biosynthesizing nano-silver by using plant and microorganism extracts at present, researches show that nano-silver bacteriostats prepared from different biological materials have great differences in physical and chemical properties, bacteriostatic activity, bacteriostatic spectrum and the like. In addition, although the amino acids, lipids, proteins, polysaccharides and other substances in the biological extract can play a role in stabilizing the nano-silver to a certain extent, aggregation still occurs in a plurality of biosynthetic nano-silver products during long-term storage, which is not beneficial to popularization and application of the nano-silver. Therefore, people are required to continuously develop and utilize new biological materials to prepare more efficient and stable nano-silver bacteriostats.
Disclosure of Invention
The invention aims to provide a method for biologically synthesizing a nano-silver composite bacteriostatic agent by adopting a lotus root extracting solution, which has mild and environment-friendly reaction conditions, is simple and easy to operate, fully exerts the synergistic bacteriostatic action of nano-silver and chitosan, achieves the remarkable bacteriostatic effect, and ensures that a composite nano-silver preparation prepared by taking the chitosan as a carrier is more stable.
A method for preparing a high-efficiency and stable composite nano-silver bacteriostatic agent by using a lotus root extract one-step method is characterized by comprising the following steps:
1. pretreatment of materials
Cleaning lotus roots, slicing, and drying to constant weight to obtain dried lotus root slices;
the lotus root is washed clean by firstly washing the lotus root with tap water and then washing the lotus root with double distilled water for 3 to 5 times;
the lotus root slices are placed in an oven to be dried to constant weight, and the temperature in the oven is controlled to be 50-80 ℃;
2. preparation of lotus root extract
Crushing and grinding the dried lotus root slices into powder, mixing the powder with an extracting agent according to the mass ratio of 1: 1-100, carrying out 100-jar 500W microwave treatment for 5-10min, heating, refluxing, centrifuging, taking supernatant, and placing the supernatant at 4 ℃ for later use;
the extractant is any one of double distilled water, ethanol, ether and acetone;
the temperature of the heating reflux is controlled to be 40-100 ℃, and the heating reflux is carried out for 0.5-10 h;
the centrifugal treatment is carried out in a centrifuge, the rotating speed of the centrifuge is controlled at 5000-10000rpm, and the centrifugation is carried out for 10-15 min;
3. preparation of chitosan solution:
weighing 0.1-3g of chitosan, adding the chitosan into 100mL of 1% glacial acid solution, and continuously stirring overnight to completely dissolve the chitosan for later use;
4. one-step method for biologically synthesizing nano silver
Adding the 1-10mL of chitosan solution into 30mL of double distilled water, adding a certain volume of silver nitrate solution, continuously stirring for 5min, then adding 0.1-10mL of lotus root extract, fixing the volume to 50mL (at the final concentration of silver nitrate, 0.01-1mol/L), and heating and refluxing to obtain the composite nano-silver bacteriostatic agent;
the temperature of the heating reflux is controlled at 40-100 ℃, and the heating reflux is carried out for 5-120 min.
The invention comprehensively utilizes the excellent antioxidant activity of polyphenol compounds and other substances in the lotus root extract to biologically reduce silver nitrate into the nano-silver bacteriostatic agent, forms monodisperse particles by taking active ingredients in the lotus root extract as a stabilizer, and further combines with chitosan to prepare the stable biological nano-silver composite bacteriostatic agent. The product fully exerts the synergistic bacteriostatic action of the biological nano-silver and the chitosan, achieves the obvious bacteriostatic effect, simultaneously realizes the biosynthesis and the carrier loading of the nano-silver by the synthesis method, has simple and convenient operation, low production cost and mild and environment-friendly reaction, and can avoid the defect that the traditional chemical synthesis method harms the environment. Antibacterial experiments show that the lotus root biosynthetic nano-silver antibacterial agent has obvious antibacterial effect on clinical drug-resistant pathogenic bacteria and aquatic pathogenic bacteria, and has wide application prospect.
Drawings
FIG. 1: example 1 of the present invention, a uv-vis absorption spectrum of a composite nano silver bacteriostatic agent was biosynthesized using a lotus root extract at different silver nitrate concentrations;
FIG. 2: example 2 of the present invention, the ultraviolet-visible absorption spectrum of the composite nano silver bacteriostatic agent was biosynthesized using the lotus root extract at different reaction times;
FIG. 3: the transmission electron microscope photo of the product prepared in 12min is synthesized in the embodiment 2 of the invention.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
Example 1
The embodiment is a preparation process for biologically synthesizing a composite nano-silver bacteriostatic agent by utilizing a lotus root extracting solution, which comprises the following preparation processes:
1. pretreatment of materials
Washing rhizoma Nelumbinis with tap water, washing with double distilled water for 5 times, slicing, oven drying at 60 deg.C to constant weight to obtain dried rhizoma Nelumbinis slices, and grinding into powder;
2. preparation of lotus root extract
Weighing the lotus root powder 10g, adding double distilled water 100mL, treating with microwave oven 100W for 10min, and heating and refluxing at 70 deg.C for 2 h. Centrifuging at 8000rpm for 10min, collecting supernatant, and storing at 4 deg.C;
3. preparation of chitosan solution:
weighing 0.5g of chitosan, adding the chitosan into 100mL of 1% glacial acid solution, and continuously stirring overnight to completely dissolve the chitosan for later use;
4. biological synthesis composite nano silver bacteriostatic agent
Adding 1mL of the chitosan solution into 30mL of double distilled water, adding silver nitrate solutions with different volumes, stirring for 5min, adding 1mL of the lotus root extract, fixing the volume to 50mL (the final concentration of silver nitrate is 0.5mM, 1.0mM, 1.5mM and 2.0mM respectively), heating and refluxing at 60 ℃ for 20min, sampling, and cooling to room temperature for detection.
5. Characterization of UV-visible absorption Spectroscopy
Scanning the prepared sample solution by an ultraviolet-visible spectrophotometer, wherein the scanning wavelength range is 300-600 nm. As can be seen from the attached figure 1, when the concentration of silver nitrate is 0.5mM, a characteristic nano-silver absorption peak generated due to surface plasmon resonance appears in a prepared sample solution near 420nm, which indicates that the nano-silver bacteriostatic agent can be successfully prepared by the method provided by the invention. And the absorption peak of the corresponding product is gradually enhanced along with the increase of the concentration of the silver nitrate, and the generated nano-silver bacteriostatic agent forms a remarkable absorption peak when the concentration of the silver nitrate reaches 2.0 mM.
Example 2
The embodiment is a preparation process for biologically synthesizing a composite nano-silver bacteriostatic agent by utilizing a lotus root extracting solution, which comprises the following preparation processes:
1. pretreatment of materials
Washing rhizoma Nelumbinis with tap water, washing with double distilled water for 5 times, slicing, oven drying at 60 deg.C to constant weight to obtain dried rhizoma Nelumbinis slices, and grinding into powder;
2. preparation of lotus root extract
Weighing the lotus root powder 10g, adding 50% ethanol 100mL, treating with microwave oven 500W for 5min, and heating and refluxing at 60 deg.C for 1 h. Centrifuging at 8000rpm for 10min, collecting supernatant, and storing at 4 deg.C;
3. preparation of Chitosan solution
Weighing 1g of chitosan, adding the chitosan into 100mL of 1% glacial acid solution, and continuously stirring overnight to completely dissolve the chitosan for later use.
4. Biological synthesis composite nano silver bacteriostatic agent
Adding 1mL of the chitosan solution into 30mL of double distilled water, adding 10mL of 10mM silver nitrate solution, stirring for 5min, adding 2mL of lotus root extract, fixing the volume to 50mL (final silver nitrate concentration is 2mM), heating and refluxing at 70 ℃ for 3min, 6min, 9min, 12min and 15min, sampling, and cooling to room temperature for detection.
5. Characterization of UV-visible absorption Spectroscopy
Scanning the prepared sample solution by an ultraviolet-visible spectrophotometer, wherein the scanning wavelength range is 300-600 nm. As can be seen from FIG. 2, the prepared sample solution has a distinct characteristic absorption peak of nano-silver near 425nm, and the absorption peak is gradually enhanced with the prolonging of the reaction time. It can be seen from this example that the synthesis efficiency of the nano-silver complex mediated by the lotus root extract is very high, and the absorption peak can be generated after the synthesis reaction is performed for 3 min.
6. Observation with a transmission electron microscope
And (3) dropwise adding 5-10 mu L of the product solution prepared in the step (4) after heating and refluxing for 12min on a copper net, drying at room temperature, and observing by using a transmission electron microscope at the voltage of 80-300 kV. As shown in figure 3, the nano silver particles biosynthesized from lotus roots are spherical, the particle size range is about 3-30nm, and the particle size is relatively uniform. As can be seen from the figure, the nano silver particles are uniformly supported on the chitosan surface in a monodispersed form. Most of the nano-silver is small particles of about 5nm, which is much smaller than the similar nano-silver preparation. The small particle size of nano silver and the high biocompatibility of chitosan are favorable for the composite nano bacteriostatic agent to be combined on the cell wall and cell membrane of pathogenic bacteria and directly enter the bacteria, and combined with sulfydryl on protease to inactivate the bacteria and inhibit the synthesis of bacterial DNA, so that the pathogenic bacteria die finally.
Comparative example 1
The comparative example is a process for biosynthesizing the nano-silver bacteriostatic agent by pure lotus roots without a carrier, and the process comprises the following preparation processes:
1. pretreatment of materials
Washing rhizoma Nelumbinis with tap water, washing with double distilled water for 5 times, slicing, oven drying at 60 deg.C to constant weight to obtain dried rhizoma Nelumbinis slices, and grinding into powder;
2. preparation of lotus root extract
Weighing the lotus root powder 10g, adding 50% ethanol 100mL, treating with microwave oven 500W for 10min, and heating and refluxing at 60 deg.C for 1 h. Centrifuging at 8000rpm for 10min, collecting supernatant, and storing at 4 deg.C.
3. Biosynthetic nano-silver bacteriostatic agent
Adding 2mL of the lotus root extract into 30mL of double distilled water, adding 10mL of 10mM silver nitrate solution, fixing the volume to 50mL (the final concentration of silver nitrate is 2mM), heating and refluxing at 70 ℃ for 20min, sampling, and cooling to room temperature for detection.
Comparative example 2
The embodiment is a preparation process for synthesizing a composite nano-silver bacteriostatic agent by a chemical method, which comprises the following preparation processes:
1. preparation of sodium citrate solution
1g of sodium citrate is weighed and dissolved in 100mL of double distilled water with stirring for later use.
2. Preparation of Chitosan solution
Weighing 1g of chitosan, adding the chitosan into 100mL of 1% glacial acid solution, and continuously stirring overnight to completely dissolve the chitosan for later use.
3. Chemically synthesized composite nano silver bacteriostat
Adding 1mL of the chitosan solution into 30mL of double distilled water, adding 10mL of 10mM silver nitrate solution, stirring for 10min, adding 5mL of the sodium citrate solution prepared in the step 1, fixing the volume to 50mL (the final concentration of silver nitrate is 2mM), heating to boil, sampling after 15min, and cooling to room temperature for detection.
Comparative example 3
The product synthesized in example 2 for 12min was evaluated in comparison with the samples of comparative examples 1 and 2 by the following procedure:
1. bacteriostatic zone experiment:
4 clinical pathogenic bacteria Escherichia coli (Escherichia coli), Staphylococcus aureus (Staphylococcus aureus), Bacillus subtilis, Pseudomonas aeruginosa (Pseudomonas aeruginosa) and 4 aquatic pathogenic bacteria are respectively selected: the antibacterial activity of the synthesized nano-silver antibacterial agent is detected by taking Vibrio anguillarum, Vibrio alginolyticus and Vibrio splendens as indicator bacteria and adopting a conventional cup and dish method to perform an antibacterial zone experiment. The specific experimental method is as follows: the clinical pathogenic bacteria to be tested are cultured in LB culture medium (tryptone 10g yeast extract 5g, NaCl 5g, distilled water to 1000mL, pH adjusted to 7.4) at 37 ℃. The marine aquatic pathogenic bacteria are cultured in 2216E culture medium (peptone 5g, yeast extract 1g, ferric phosphate 0.01g, and aged seawater with constant volume of 1000mL) at 28 deg.C. Diluting the test bacteria cultured to logarithmic growth period with normal saline to 1 × 106CFU/mL, 100. mu.L of the suspension was evenly spread on a corresponding solid medium, an Oxford cup (cup outer diameter 8mm) was placed on the medium, 20. mu.L of the samples of example 2, comparative example 1 and comparative example 2 were added to different petri dishes, 20. mu.L of each of chitosan, lotus root extract and sodium citrate was used as a control, the petri dishes were placed in a constant temperature incubator overnight for culture, and the diameter of the zone of inhibition was observed. All experiments were repeated three times and the results are expressed as mean ± standard deviation, and the specific experimental results are shown in the attached table 1. It can be seen from the table that the lotus root extract and the sodium citrate solution are in a pairThe tested pathogenic bacteria have no bacteriostatic activity; the chitosan has certain bacteriostatic activity and can generate a smaller bacteriostatic zone around the oxford cup; the lotus root biosynthetic composite nano-silver bacteriostatic agent in the embodiment 2, the lotus root biosynthetic pure nano-silver bacteriostatic agent in the comparative example 1 and the composite nano-silver bacteriostatic agent prepared by the chemical reduction method in the comparative example 2 have obvious bacteriostatic rings on all clinical pathogenic bacteria and aquatic pathogenic bacteria to be tested. Further comparison shows that the inhibition zones of the example 2 are much larger than those of the comparative examples 1 and 2, and the antibacterial advantage is stronger, which indicates that the nano-silver and chitosan biosynthesized from lotus root exert synergistic antibacterial activity and can achieve more obvious antibacterial effect.
Attached table 1 diameter of inhibition zone of nano-silver preparation to pathogenic bacteria to be tested
2. Minimum inhibitory concentration experiment:
clinical drug-resistant pathogenic bacteria staphylococcus aureus is used as a test bacterium, and the Minimum Inhibitory Concentration (MIC) of the prepared nano-silver bacteriostatic agent is determined by a two-fold dilution method, so that the antibacterial activity of the prepared nano-silver is quantitatively evaluated. Two-fold gradient dilution of three test samples, equal volume addition of 1X 106And (3) culturing the CFU/mL fresh staphylococcus aureus culture solution at the constant temperature of 37 ℃ for 24h, observing the growth condition of the bacterial solution, wherein the minimum sample concentration of the non-growing bacteria is MIC. As can be seen from the attached table 2, the MIC of the sample in the example 2 is 6.25 μ g/mL, which is obviously lower than 25 μ g/mL of the sample in the comparative example 1 and 50 μ g/mL of the sample in the comparative example 2, which indicates that the composite nano-silver bacteriostatic agent biosynthesized by the lotus root extract can achieve the effect of inhibiting the growth of pathogenic bacteria at a lower dosage, and therefore, the bacteriostatic activity is stronger.
Attached table 2 determination of Minimum Inhibitory Concentration (MIC) of nano-silver preparation to pathogenic bacteria to be tested
Note: "+" indicates turbidity, and "-" indicates no turbidity
3. Stability test:
because the nano silver has large specific surface area and smaller particle size, agglomeration is easy to occur, which will influence the exertion of the antibacterial effect. Therefore, the stability becomes one of the important evaluation indexes of the bacteriostatic agent. Observing the three nano-silver solutions after the three nano-silver solutions are placed for three months at room temperature in a dark place, finding that the comparative example 1 and the comparative example 2 have the phenomena of turbid solutions and precipitation separation, and showing that the diameters of inhibition zones of the solutions on pathogenic bacteria to be tested are obviously reduced by the inhibition zone experiment; the biosynthetic nano silver bacteriostatic agent in the embodiment 2 still keeps clear and transparent, has small change of the diameter of a bacteriostatic circle of pathogenic bacteria to be tested, and still has remarkable bacteriostatic effect. Therefore, the product prepared by the invention has the advantages of obvious bacteriostatic effect, stable performance and good application and popularization values.
Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that changes, modifications, substitutions and alterations can be made in these embodiments without departing from the principles and spirit of the invention, the scope of which is defined in the appended claims and their equivalents.
Claims (7)
1. A method for preparing a high-efficiency and stable composite nano-silver bacteriostatic agent by using a lotus root extract one-step method is characterized by comprising the following steps:
1) pretreatment of materials
Cleaning lotus roots, slicing, and drying to constant weight to obtain dried lotus root slices;
2) preparation of lotus root extract
Crushing and grinding the dried lotus root slices into powder, mixing the powder with an extracting agent according to the mass ratio of 1: 1-100, performing 100-fold microwave treatment at 500W for 5-10min, heating and refluxing, centrifuging, and taking supernatant liquid to be placed at 4 ℃ for later use;
3) preparation of chitosan solution:
weighing 0.1-3g of chitosan, adding the chitosan into 100mL of 1% glacial acid solution, and continuously stirring overnight to completely dissolve the chitosan for later use;
4) one-step method for biologically synthesizing nano silver
And (3) adding the 1-10mL of chitosan solution into 30mL of double distilled water, adding a certain volume of silver nitrate solution, continuously stirring for 5min, then adding 0.1-10mL of lotus root extract, fixing the volume to 50mL, and heating and refluxing to obtain the composite nano-silver bacteriostatic agent.
2. The method for preparing the efficient and stable composite nano-silver bacteriostatic agent by using the one-step method of the lotus root extract as claimed in claim 1, wherein the step of washing the lotus root in the step 1) is to wash the lotus root with tap water and then wash the lotus root with double distilled water for 3-5 times.
3. The method for preparing the efficient and stable composite nano-silver bacteriostatic agent by using the one-step method of the lotus root extract as claimed in claim 1, wherein the lotus root slices in the step 1) are placed in an oven to be dried to constant weight, and the temperature in the oven is controlled to be 50-80 ℃.
4. The method for preparing the efficient and stable composite nano-silver bacteriostatic agent by using the one-step method of the lotus root extract as claimed in claim 1, wherein the extractant in the step 2) is any one of double distilled water, ethanol, ether and acetone.
5. The method for preparing the efficient and stable composite nano-silver bacteriostatic agent by using the one-step method of the lotus root extract as claimed in claim 1, wherein the temperature of the heating reflux in the step 2) is controlled to be 40-100 ℃, and the heating reflux is carried out for 0.5-10 h.
6. The method for preparing the efficient and stable composite nano-silver bacteriostatic agent by using the one-step method of the lotus root extract as the claim 1, wherein the centrifugation treatment in the step 2) is performed in a centrifuge, the rotation speed of the centrifuge is controlled at 5000-10000rpm, and the centrifugation is performed for 10-15 min.
7. The method for preparing the efficient and stable composite biological nano-silver bacteriostatic agent by using the one-step method of the lotus root extract as claimed in claim 1, wherein the heating reflux temperature in the step 4) is controlled at 40-100 ℃, and the heating reflux time is controlled at 5-120 min.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010036131.0A CN111202092B (en) | 2020-01-14 | 2020-01-14 | Method for preparing efficient and stable composite nano-silver bacteriostatic agent by one-step method through lotus root extract |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010036131.0A CN111202092B (en) | 2020-01-14 | 2020-01-14 | Method for preparing efficient and stable composite nano-silver bacteriostatic agent by one-step method through lotus root extract |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN111202092A true CN111202092A (en) | 2020-05-29 |
| CN111202092B CN111202092B (en) | 2021-05-18 |
Family
ID=70782788
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202010036131.0A Active CN111202092B (en) | 2020-01-14 | 2020-01-14 | Method for preparing efficient and stable composite nano-silver bacteriostatic agent by one-step method through lotus root extract |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN111202092B (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112715547A (en) * | 2020-12-31 | 2021-04-30 | 南京启佑生物科技有限公司 | Chitosan-lysozyme composite bacteriostatic agent and preparation method and application thereof |
| CN113621153A (en) * | 2021-08-05 | 2021-11-09 | 集美大学 | Plant extract synthesized nano-silver multifunctional degradable food packaging material and preparation method thereof |
| CN114029503A (en) * | 2021-11-12 | 2022-02-11 | 中国科学院合肥物质科学研究院 | Method and application for green synthesis of nano platinum by using lotus flower aqueous extract |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1653907A (en) * | 2005-01-27 | 2005-08-17 | 浙江大学 | Method for preparing nanometer silver solution and nanometer silver powder by using high polymer as stabilizer |
| CN106513707A (en) * | 2016-12-07 | 2017-03-22 | 鲁东大学 | Nano silver bacteriostatic agent biosynthesized through blueberry leaf extracting solution and preparation process of nano silver bacteriostatic agent |
| CN107439593A (en) * | 2017-08-09 | 2017-12-08 | 范佳晨 | A kind of silver-colored chitosan anti-bacteria material and preparation method thereof |
-
2020
- 2020-01-14 CN CN202010036131.0A patent/CN111202092B/en active Active
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1653907A (en) * | 2005-01-27 | 2005-08-17 | 浙江大学 | Method for preparing nanometer silver solution and nanometer silver powder by using high polymer as stabilizer |
| CN106513707A (en) * | 2016-12-07 | 2017-03-22 | 鲁东大学 | Nano silver bacteriostatic agent biosynthesized through blueberry leaf extracting solution and preparation process of nano silver bacteriostatic agent |
| CN107439593A (en) * | 2017-08-09 | 2017-12-08 | 范佳晨 | A kind of silver-colored chitosan anti-bacteria material and preparation method thereof |
Non-Patent Citations (3)
| Title |
|---|
| 冯晓燕等: "壳聚糖-银纳米微粒表面修饰木纤维的制备及抗菌性能研究 ", 《生物质化学工程》 * |
| 张雨菲 等: "壳聚糖纳米银溶液的稳定性及在织物抗菌整理上的应用", 《高等学校化学学报》 * |
| 王蓓: "莲藕品种对莲藕汁抗氧化性的影响——莲藕汁的抗氧化性研究之一", 《江苏调味副食品》 * |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112715547A (en) * | 2020-12-31 | 2021-04-30 | 南京启佑生物科技有限公司 | Chitosan-lysozyme composite bacteriostatic agent and preparation method and application thereof |
| CN113621153A (en) * | 2021-08-05 | 2021-11-09 | 集美大学 | Plant extract synthesized nano-silver multifunctional degradable food packaging material and preparation method thereof |
| CN114029503A (en) * | 2021-11-12 | 2022-02-11 | 中国科学院合肥物质科学研究院 | Method and application for green synthesis of nano platinum by using lotus flower aqueous extract |
Also Published As
| Publication number | Publication date |
|---|---|
| CN111202092B (en) | 2021-05-18 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN111202092B (en) | Method for preparing efficient and stable composite nano-silver bacteriostatic agent by one-step method through lotus root extract | |
| Mehwish et al. | Green synthesis of a silver nanoparticle using Moringa oleifera seed and its applications for antimicrobial and sun-light mediated photocatalytic water detoxification | |
| Shang et al. | Microwave-assisted extraction, partial purification and biological activity in vitro of polysaccharides from bladder-wrack (Fucus vesiculosus) by using deep eutectic solvents | |
| Um et al. | Ultrasound-assisted extraction and antioxidant activity of phenolic and flavonoid compounds and ascorbic acid from rugosa rose (Rosa rugosa Thunb.) fruit | |
| Sathishkumar et al. | Phyto-synthesis of silver nanoscale particles using Morinda citrifolia L. and its inhibitory activity against human pathogens | |
| CN106513707B (en) | A kind of nano silver antibacterial agent and its preparation process using blueberry leaf extract biosynthesis | |
| Karimi et al. | Bioactive compounds from by-products of eggplant: Functional properties, potential applications and advances in valorization methods | |
| Chen et al. | Characterization and antioxidant activity of wheat bran polysaccharides modified by Saccharomyces cerevisiae and Bacillus subtilis fermentation | |
| Velmurugan et al. | Extraction of natural colorant from purple sweet potato and dyeing of fabrics with silver nanoparticles for augmented antibacterial activity against skin pathogens | |
| CN111296506B (en) | Method for preparing efficient bacteriostatic agent by using reed leaf extract | |
| Gao et al. | Optimized ultrasound-assisted extraction of total polyphenols from Empetrum nigrum and its bioactivities | |
| Chen et al. | Optimization of ultrasonic-assisted extraction, refinement and characterization of water-soluble polysaccharide from Dictyosphaerium sp. and evaluation of antioxidant activity in vitro | |
| CN113234552B (en) | Hop polysaccharide nano particle and preparation method and application thereof | |
| Nazarudin et al. | Metabolic variations in seaweed, Sargassum polycystum samples subjected to different drying methods via 1H NMR-based metabolomics and their bioactivity in diverse solvent extracts | |
| Aghamirzaei et al. | Antioxidant, antimicrobial and cytotoxic activities of biosynthesized gold nanoparticles (AuNPs) from Chinese lettuce (CL) leave extract (Brassica rapa var. pekinensis) | |
| CN109702218B (en) | Method for preparing nano-silver particles by using phyllanthus emblica extract, product and application | |
| CN111184024A (en) | Method for preparing nano-silver composite bacteriostatic agent by using thyme leaf extracting solution | |
| CN109529784B (en) | Gradient adsorption nano-composite of polyphenol and the like and preparation method thereof | |
| Saleh et al. | Exploitation of cantaloupe peels for bacterial cellulose production and functionalization with green synthesized Copper oxide nanoparticles for diverse biological applications | |
| Wu et al. | Polyphenols from Artemisia argyi leaves: Environmentally friendly extraction under high hydrostatic pressure and biological activities | |
| Trivedi et al. | Statistically optimized synthesis of silver nanocubes from peel extracts of Citrus limetta and potential application in waste water treatment | |
| Hodhodi et al. | Effect of different extraction conditions on phlorotannin content and antioxidant activity of extract from brown algae (Sargassum angustifolium) | |
| ASSAW et al. | Antioxidant and antibacterial activities of polysaccharides and methanolic crude extracts of local edible red seaweed Gracilaria sp. | |
| Rao et al. | A green approach to synthesize silver nanoparticles from natural polymer for biomedical application | |
| Wizi et al. | Analysis of Bioactive Compounds from different Algae samples extracted with Ultrasound: characterizations, phytochemical contents and antioxidant potentials |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant | ||
| PE01 | Entry into force of the registration of the contract for pledge of patent right |
Denomination of invention: A method for preparing efficient and stable composite nano silver antibacterial agent by one-step method of lotus root extract Effective date of registration: 20211216 Granted publication date: 20210518 Pledgee: Yantai financing guarantee Group Co.,Ltd. Pledgor: LUDONG University Registration number: Y2021980015152 |
|
| PE01 | Entry into force of the registration of the contract for pledge of patent right | ||
| PC01 | Cancellation of the registration of the contract for pledge of patent right |
Date of cancellation: 20220317 Granted publication date: 20210518 Pledgee: Yantai financing guarantee Group Co.,Ltd. Pledgor: LUDONG University Registration number: Y2021980015152 |
|
| PC01 | Cancellation of the registration of the contract for pledge of patent right |