KR102052113B1 - Absorbent comprising polymer of a red algae extract and a water-soluble chitin as effective component and having improved absorption and antimicrobial activity and production method thereof - Google Patents

Abstract

The present invention relates to an absorbent which comprises a polymer of a red algae extract and aqueous chitin as an effective component and has increased absorption power and antibacterial activity, and to a method for manufacturing the absorbent. More specifically, the polymer of a red algae extract and aqueous chitin is a natural polymer absorbent which is harmless to the human body, is environmentally friendly, has excellent absorption power and antibacterial activity, and has an excellent effect for blocking harmful materials, thereby being usefully used for industries related to hygiene products such as diapers, sanitary pads, etc.

Description

Absorbent comprising polymer of a red algae extract and a water-soluble chitin as effective component and having improved absorption and antimicrobial activity and production method

The present invention includes a polymer of red algae extract and a water-soluble chitin as an active ingredient, and relates to an absorbent and a method for preparing the same, wherein absorption and antibacterial activity are enhanced.

Superabsorbent polymer (SAP) refers to a crosslinked polymer capable of absorbing and expanding large amounts of liquid to form hydrogels and retain the absorbed liquid under constant pressure. Representative synthetic polymer absorbers include crosslinked hydroalkyl (meth) acrylic acid, N-vinylpyrrolidone, ethyl oxide, acrylamide, (meth) acrylic acid, poly (vinyl alcohol), and crosslinked poly (acrylic acid) (PAA). Accounts for most of the market.

Products based on the polymer absorbents currently on the market include a variety of hygiene products, such as women's sanitary napkins, infants and adult diapers, most of which use polymer absorbers harmful to the human body based on petrochemicals. The hygiene products made of the petrochemical-based polymer absorbents are not biodegradable after use, which causes various serious environmental and economic problems during disposal or incineration during disposal. It has been very active both internally and externally, but its performance is very low compared to conventional chemicals. In addition, fever, skin sores and itching due to harmful substances are generated.

In addition, there is no global market dominant technology, and there is a lack of polymer absorber technology of biodegradable and eco-friendly materials that are harmless to humans. Therefore, in order to cope with the global common problems of environment and petroleum depletion, There is a need to develop products that replace existing petroleum based polymers with environmentally friendly polymers.

Meanwhile, Korean Patent No. 1013365 discloses a nonwoven fabric containing seaweed fibers and a method for manufacturing the same, and Korean Patent Publication No. 2018-0028244 discloses a method for preparing a natural polymer absorbent capable of absorbing moisture. Doing. However, 'absorbents and methods for preparing the same, which include a polymer of red algae extract and a water-soluble chitin as active ingredients, and have enhanced absorption and antibacterial activity, have not been disclosed.

The present invention is derived from the above requirements, the inventors of the present invention, the polymer of red algae extract and water-soluble chitin N-acetylpolyglucosamine (N-acetylpolyglucosamine) as well as remarkable absorption ability compared to red algae extract or water-soluble chitin alone, Staphylococcus aureus (Staphylococcus aureus), which causes thrush, cystitis, itching, such as E. coli (Escherichia coli ), Candida albicans and Pseudomonas Aeruginos a ) excellent antibacterial activity, by confirming that effectively blocking harmful substances, the present invention was completed.

In order to solve the above problems, the present invention comprises a polymer of red algae extract and water-soluble chitin as an active ingredient, and provides an absorbent, characterized in that the absorption and antimicrobial activity is enhanced.

In addition, the present invention provides a hygiene article comprising the absorbent.

In addition, the present invention 1) adding 1 to 2 parts by volume of water based on 1 part by weight of red algae, the first extraction for 2 to 8 hours at pH 6 ~ 7 and 70 ~ 130 rpm at 70 ~ 95 ℃; 2) extracting the red algae primary extract obtained in step 1) for 2 to 9 hours at a temperature of 60 to 75 ° C .; 3) separating and purifying the red algae secondary extract obtained in step 2) and then sterilizing; 4) gelling the red algae secondary extract sterilized in step 3) at room temperature; 5) lyophilizing and grinding the gelled red algae secondary extract in step 4) to prepare a powder of 50-200 mesh; And 6) the red algae powder obtained in step 5) and the water-soluble chitin are mixed, and then water is added to polymerize at a temperature of 50-70 ° C. at a pH of 6-7 and 100-400 rpm to extract red algae and water-soluble chitin. It provides a method of producing a water absorbent, the absorbent is enhanced, including the step of preparing a polymer;

The polymer of the red algae extract and the water-soluble chitin of the present invention are natural polymer absorbents, which are harmless to the human body, are environmentally friendly, have excellent absorption and antibacterial properties, and are excellent in blocking harmful substances. It can be useful.

Figure 1 shows a schematic diagram of the manufacturing process of the hygiene article comprising the polymer of the red algae extract and the water-soluble chitin of the present invention and including an absorbent having enhanced absorption and antibacterial activity.

In order to achieve the object of the present invention, the present invention comprises a polymer of red algae extract and water-soluble chitin as an active ingredient, and provides an absorbent, characterized in that the absorption and antimicrobial activity is enhanced.

In the absorbent according to an embodiment of the present invention, the red alga may be Irish moss ( Chondrus crispus ), preferably Hypnea Musciformis ) or round silk leaves ( Iridaea cordata ), more preferably may be used by mixing the hooked silk and round silk leaves in a weight ratio of 1 to 80: 1 to 80, most preferably of 49: 1 It may be used by mixing in a weight ratio, but is not limited thereto.

In addition, the water-soluble chitin may be N-acetylpolyglucosamine, but is not limited thereto.

In addition, the antimicrobial activity may be, but is not limited to, Staphylococcus aureus , Escherichia coli , Candida albicans , or Pseudomonas aeruginosa .

In addition, the absorbent is characterized in that it has a harmful substance blocking effect, the harmful substance is ethylbenzene, chloroform, chloroform, methylene chloride, tetrachloroethene, benzene , Toluene, styrene, trichloroethene, o-xylene, p-xylene / m-xylene, xylene It may be one or more selected from the group consisting of (xylene) and hexane (hexane), but is not limited thereto.

In addition, the present invention provides a hygiene article comprising the absorbent.

The hygiene article may be any one selected from the group consisting of a diaper, a sanitary napkin, an incontinence pad, a left pad, a hemorrhoid pad, a wet tissue, and a mask, but is not limited thereto.

In addition, the present invention

1) adding 2 to 10 parts by volume of water based on 1 part by weight of red algae and performing primary extraction at 70 to 95 ° C. for 2 to 8 hours at pH 6 to 7 and 70 to 130 rpm;

2) extracting the red algae primary extract obtained in step 1) for 2 to 9 hours at a temperature of 60 to 75 ° C .;

3) separating and purifying the red algae secondary extract obtained in step 2) and then sterilizing;

4) gelling the red algae secondary extract sterilized in step 3) at room temperature;

5) lyophilizing and grinding the gelled red algae secondary extract in step 4) to prepare a powder of 50-200 mesh; And

6) After mixing the red algae powder and the water-soluble chitin obtained in step 5), water was added to polymerize at a pH of 6-7 and 100-400 rpm at a temperature of 50-70 ° C. to extract the red algae extract and the water-soluble chitin. It provides a method for producing a water absorbent, the absorbent is enhanced, including the step of preparing a polymer;

In the method for preparing an absorbent having enhanced absorption and antibacterial activity according to an embodiment of the present invention, the red algae powder and the water-soluble chitin obtained in step 5) have a weight ratio of 1 to 10: 1 to 10, preferably 4 to 6: It may be mixed in a weight ratio of 1, but is not limited thereto.

According to one embodiment of the present invention, the method for preparing the absorbent having enhanced absorption and antibacterial activity is most preferably,

1) adding 6 parts by weight of water with respect to 1 part by weight of red algae, the first extraction for 4 hours at pH 6.5 and 100 rpm at 80 ~ 85 ℃;

2) extracting the red algae primary extract obtained in step 1) for 2 hours at a temperature of 70 ° C. for 12 hours;

3) separating and purifying the red algae secondary extract obtained in step 2) and then sterilizing;

4) gelling the red algae secondary extract sterilized in step 3) at room temperature;

5) lyophilizing and grinding the gelled red alga secondary extract in step 4) to prepare a powder of 100 mesh; And

6) The red algae powder obtained in step 5) and the water-soluble chitin were mixed at a weight ratio of 5: 1, and then water was added to polymerize the mixture at a temperature of 60 ° C. at pH 6.5 and 300 rpm to obtain the red algae extract and the water-soluble chitin. Preparing a polymer; may include, but is not limited thereto.

In addition, the aroma herbal oil may be additionally added when the red algae powder and the water-soluble chitin are mixed in the step 6), but are not limited thereto.

Hereinafter, the embodiment of the present invention will be described in detail. However, the following examples are merely to illustrate the invention, but the content of the present invention is not limited to the following examples.

Production Example  1. Red algae absorbent

The extraction stirrer was equipped with a stirring motor capable of rotating the stirring impeller to be stirred at 100 to 1500 rpm, and a temperature controller and a supply pipe were installed to control the temperature at 20 to 100 ° C. pH 6.0-7.0 was maintained and installed to be automatically added according to the pH sensor. Red algae exhibited activity at neutral pH 6.0-7.0 because of their degrading properties in neutral. The amount of purified water was automatically adjusted by attaching a level sensor, a temperature TIC sensor, and a concentration bric meter (%).

Red algae used in the present invention is an Irish moss ( Chondrus) crispus , Irish moss) Hypnea m usciformis and round silk leaves ( Iridaea cordata ) were used, and 100 kg of the mixture of the rounded silk leaves and round silk leaves in a 49: 1 weight ratio was extracted from 1 ton. Into a stirrer and 600L of purified water as an extraction solvent, the extraction reaction temperature was 80 ~ 85 ℃, pH was maintained 6.5, and the first extraction for 4 hours to circulate up and down simultaneously with stirring at 100 rpm. Thereafter, the obtained first red algae extract was circulated up and down without stirring, and slowly extracted for 12 hours while maintaining at 70 ° C., and the extraction reaction solution was subjected to an ultrafiltration membrane separation and purification device to remove impurities. Purified red algae extract (hereinafter referred to as 'red algae absorber') was purified. The red algae absorbent was sterilized at 100 ° C. for 30 minutes to prevent decay and remove E. coli.

The sterilized red algae absorbents of about 700L were placed in 140 trays of 570 cm x 630 cm x 30 cm in height, each 5 kg and left to gel at room temperature (15-25 ° C). The red algae absorbent which was completely gelled after 6 hours was rapidly frozen at -40 ° C for 12 hours and vacuum-dried at -70 ° C for 24 hours using an industrial lyophilizer. Thereafter, the lyophilized red algae powder crystals were pulverized using a pin mill grinder, and then powder red algae absorbent (100 mesh) particles were obtained by using a twist screen (ø1,500). .

Production Example  2. Preparation of Water Soluble Chitin Solution

N-acetylpolyglucosamine (N-acetylpolyglucosamine), a water-soluble chitin, was purchased from KOSA (Korea), and polyvinylpyrrolidone (PVP) was 1.3 × 10 ^4. It was purchased from Aldrich, USA as having a molecular weight (M _w ) of ˜1.46 × 10 ⁵ .

Water Soluble Chitin Solution A water-soluble chitin solution was prepared by dissolving N-acetylpolyglucosamine in purified water (pH 6.0-7.0). And polyvinylpyrrolidone (PVP) was dissolved in purified water at 30 ℃ and stirred for 1 hour to prepare a 10% (v / v) polyvinylpyrrolidone solution. Thereafter, the prepared 30ml water-soluble chitin solution and 100ml polyvinylpyrrolidone solution were mixed in a stirrer, adjusted to pH 6.0-7.0, and the temperature in the stirrer was heated to 60 ° C., whereby a transparent liquid phase was formed. 50 ml of distilled water was added to the clear liquid solution to make a stable solution at 30 ° C., and then nitrogen gas was introduced into the stirrer and mixed under agitation at 30 ° C. for 2 hours in a nitrogen gas state, followed by a reaction temperature of 50 ° C. The mixture was stirred at 12,000 rpm for about 6 hours until the mixed solution of water-soluble chitin and polyvinylpyrrolidone stabilized with each other. When the emulsion particles of the two solutions were stabilized, the temperature in the stirrer was increased to 70 ° C. and the stirring speed was increased. Condensation reaction was carried out while controlling the pH to 6.0-7.0 by minimizing foam formation for 3 hours while maintaining at 180 rpm. 'Water soluble chitin') was prepared and used in Preparation Example 4 below.

When mixing polyvinylpyrrolidone and water-soluble chitin, polyvinylpyrrolidone solution is produced even at room temperature because of very good compatibility. Polyvinylpyrrolidone has -NH and -COOH groups as a part of the pyrrolidone ring is ring-opened, and it has -COOH group at the end of the chain and has anionic property. do. Since water-soluble chitin, a cationic polymer, and anionic ring-opened polyvinylpyrrolidone are electrostatically bound to have high compatibility and binding properties, water-soluble chitin is not hardened when added to polyvinylpyrrolidone. It can be confirmed that it is maintained as.

Production Example  3. Aromatic Herb Solution Preparation

The raw materials of aromatic herbs include solutions such as cypress (hinokithiol), phytoncide (cypress, pine and pine), eucalyptus, lavender, rosemary, rose, jasmine, and aloe. 90 ml of 10% polyvinylpyrrolidone solution was added to a reactor equipped with a cooler, a pH sensor, an acid solution and an alkaline solution inlet tube, and 10 ml of each aromatic herb solution to be obtained was added to the stirrer to adjust the pH to 5.5 to 6.0. The emulsion was obtained while stirring at 1,200 rpm for 30 minutes while adjusting to.

However, in the present invention, the aromatic herbal capsule oil was used by adding or excluding according to the taste of the consumer. Aromatic herbal capsule oils are available in a variety of varieties, including cypress (hinokithiol), phytoncide (cypress, pine, pine), eucalyptus, lavender, rosemary, rose, jasmine and aloe.

Production Example  4. Preparation of Red Algae Extract and Water-Soluble Chitin

The red algae extract powder and the water-soluble chitin prepared according to Preparation Examples 1 and 2 were mixed at a weight ratio of 5: 1, and then water was added to the mixture to be stirred at a temperature of 60 ° C. at 6.5 and 200 rpm. Subsequently, a new polymer absorbent is formed by a polymerization in which a red algae absorbent powder and a water-soluble chitin are further added, stirred and repeatedly combined to form a polymer.

Production Example  5. Absorbent Dyeing

In order to dye the polymer of the prepared red algae extract and the water-soluble chitin, dyeing was performed under the conditions shown in Table 1 below. Specifically, the liquid type dyeing machine is sealed in a housing, and the dye inlet / outlet connected to the inlet / outlet and the salt bath / wash bath and the flushing water inlet / outlet can be opened and closed to continuously perform dyeing and washing in the same dyeing machine. In addition, a liquid dyeing machine which can simultaneously process a large amount of fibers (cotton fabric) and a nonwoven fabric with a small manpower, and can obtain a uniform salt, enables high quality and industrialization of natural dyeing (Table 1).

Absorbent Dye Cotton or nonwoven Natural dyeing fibers (cotton fabrics) or non-woven fabrics for sanitary napkins,
Plain weave 120g / m ² , width 60 inches, length 100yd Prepared Solution 25 kg (3 times diluted with water) Deposition temperature 70 ℃ Deposition time One hour 30 minutes (60 minutes of dyeing, water washing 30 minutes)

Example  1. Check absorption

Water absorption capacity was measured for each particle (100 mesh) of the red algae extract obtained in Preparation Example 1, the red algae extract obtained in Preparation Example 4, and the polymer of water-soluble chitin. Tea bag test was used to determine the absorbency of the water by referring to the certified absorbency test method (KS P ISO 17190-5). In the tea bag test, 0.1 g of red algae absorbent particles were put into a tea bag and soaked in 100 ml of water for each hour (10 seconds to 30 minutes), and after a predetermined time, the tea bag was removed from the water and weighed. Tea bags containing no red algae absorber particles were weighed according to the test method, and the amount of water (absorbent capacity) absorbed by the red algae absorber particles for a predetermined time (10 seconds to 30 minutes) was calculated as follows.

Absorption Capacity (g / g) = (Wt-(Ww + Wd)) / Wd

The amount of water absorbed by the red algae absorber particles (g) = Wt-(Ww + Wd)

Wt: Weight of tea bag containing red algae absorbent particles after water immersion for a certain time (10 seconds to 30 minutes)

Ww: Weight of tea bag without red algae absorbent particles after soaking in water for a certain time (10 seconds to 30 minutes).

Wd: Weight of red algae absorbent particles used in the experiment

As a result, as shown in Table 2 below, the polymer particles of the red algae extract powder and the water-soluble chitin of the present invention had a water-absorbing capacity of 1,335 to a maximum of 4,256 g, whereas the red algae extract powder alone particles had an absorption capacity of 843 to 1,520 g. In addition, it was confirmed that not only the absorbing ability of the red algae extract powder and the water-soluble chitin polymer of the present invention was remarkably excellent, but also that the absorbing capacity of commercially available absorbents was improved.

Absorption capacity measurement result division Absorption time 10 sec 30 seconds 1 min 10 minutes 30 minutes Absorption capacity (g) Polymer Absorbents of Red Algae Extracts and Water Soluble Chitin 1,335 g 1664 g 2,359 g 3,293 g 4,256 g Red algae extract absorbent 843 g 962 g 1,210g 1,354 g 1,520 g Commercial absorbent 1,324 g 1,648 g 2250 g 3,001 g 3,628 g

Example  2. Color fastness  Confirm

Wash fastness (KS K 0430-2001, A-1, 40 ± 2 ° C.), friction fastness (by KS K 0430-2001, A-1, 40 ± 2 ° C) by the test method according to the Korean Industrial Standard for cotton and nonwoven fabrics to which the red algae extract and the water-soluble chitin polymer were coated. KS K 0650-2001), daylight fastness (KS K 0700-1990, fade meter, BLUE SCALE) and sweat fastness (KS K 0715-2002) were measured, as shown in the following Table 3 to Table 6 Color fastness is cotton 4-5 grade, non-woven fabric 3-4 grade, friction fastness is dry grade 4-5 grade, wet state 3-4 grade, daylight fastness grade 4 and sweat fastness is both cotton cloth and nonwoven grade 4-5 grade. It was confirmed that the red algae extract of the present invention and the polymer of the water-soluble chitin is dyed cotton and non-woven fabric almost no discoloration.

Color fastness division Color fastness
(Test method: KS K 0430-2001, A-1, 40 ± 2 ° C) Fading Grade 4 pollution Cotton fabric 4-5 class Non-woven 3-4 grade

Friction fastness division Friction fastness
(Test Method: KS K 0650-2001) Dry state 4-5 class Wet state 3-4 grade

Daylight fastness division Daylight fastness
(Test method: KS K 0700-1990, fade meter, BLUE SCALE) 20 Standard Fade Time Level 4 or higher

Sweat fastness division Sweat fastness
(Test Method: KS K 0715-2002) Acid fading 4-5 class pollution Cotton fabric 4-5 class Non-woven 4-5 class Alkaline fading 4-5 class pollution Cotton fabric 4-5 class Non-woven 4-5 class

Example  3. Antibacterial activity

Antimicrobial activity against harmful microorganisms was determined by the KS K 0693: 2016 test method of the National Institute of Standards and Technology for the polymer of the red algae extract and the water-soluble chitin of the present invention (Table 7). As a result, the polymer of the red algae extract and the water-soluble chitin of the present invention are Staphylococcus aureus , Escherichia coli), Candida albicans (Candida albicans) and, while showing excellent antibacterial activity more than 97% of the luge labor (Pseudomonas aeruginosa) in Pseudomonas, in the case of a red algae extract powder or water-soluble chitin alone, or no antimicrobial activity for E. coli, Candida and Pseudomonas, except for S. aureus of 10% It showed less than antibacterial activity (Table 8 to Table 10).

Harmful microorganisms Harmful microorganisms Symptom Staphylococcus aureus ATCC 6538 Atopy, itching Esherichia coli ATCC 25922 Cystitis Induction Candida albicans ATCC 10231 Allergy, vaginitis Pseudomonas aeruginos a ATCC 15442 Cystitis, skin disease

Example  4. Blocking harmful substances

12 kinds of VOCs (Volatile Oragnic) through GC-MS analysis with reference to EPA (Environmental Protection Agency) 5021 method for the nonwoven fabric dyeing the prepared red algae extract and the water-soluble chitin polymer absorbent Compounds) were detected. As a result, it was confirmed that all 12 species were not detected as disclosed in Tables 11 and 12 below.

Example  5. Consumer Test Survey

After dyeing the polymer of the red algae extract and the water-soluble chitin of the present invention on a nonwoven fabric, diapers and women's sanitary napkin linings were prepared. Linings, such as diapers and women's sanitary napkins, should be free of skin irritation, feel good, deliver moisture quickly to the absorbent core, and have good dryness.

As a result of preparing and using diaper and women's sanitary napkin lining using the polymer of the red algae extract and the water-soluble chitin of the present invention, it was surveyed that the quick absorbency and skin feel were excellent and there was no irritation to the skin. Even when worn longer than sanitary napkins, it was confirmed that the skin had less soreness and less skin irritation (Table 13).

In addition, the skin protection of the sanitary napkin and the absorbency of the physiological secretion of the polymer of the red algae extract and the water-soluble chitin were evaluated. In order to make the same condition as women's menstrual discharge, 10ml of fresh pig blood was added to measure the time when all the pig blood was permeated from the surface of the absorbent. Both suction and permeability were better than sanitary napkin. Skin protection was determined to be excellent if the wearer of the present invention is continuously worn for 24 hours and there is no damage or itching due to a bad part of the wearer when the skin is damaged. Table 14).

Consumer Survey of Sanitary Napkin Dyeing Red Algae Extract Powder of the Present Invention and Polymer of Water Soluble Chitin division Skin texture Convenience degree Fit Very good 90% 75% 80% good 10% 25% 20% no effect 0% 0% 0%

division Of the present invention
diaper city
diaper Of the present invention
sanitary pad city
sanitary pad Absorbency
(Pig blood intake time) 7 sec 12 seconds 7 sec 11 seconds Skin protection Great itch Great itch

Claims (10)

It has antimicrobial activity against Staphylococcus aureus , Escherichia coli , Candida albicans and Pseudomonas aeruginosa , and its water absorption is 10 seconds to 30 minutes. Absorbent comprising a polymer of red algae extract and N-acetylpolyglucosamine, characterized in that 1.58 to 2.8 times higher than red algae extract in minutes. The absorbent of claim 1, wherein the red algae is Hypnea m usciformis or Iridaea cordata . delete delete The method of claim 1, wherein the absorbent is ethylbenzene, chloroform, methylene chloride, tetrachloroethene, benzene, toluene, styrene, Does not contain trichloroethene, o-xylene, p-xylene / m-xylene, xylene and hexane Absorbent, characterized in that not. delete A hygiene product comprising the absorbent of any one of claims 1, 2 and 5. The hygiene article according to claim 7, wherein the hygiene article is any one selected from the group consisting of a diaper, a sanitary napkin, an incontinence pad, a left pad, a hemorrhoid pad, a wet tissue, and a mask. 1) adding 2 to 10 parts by volume of water based on 1 part by weight of red algae and performing primary extraction at 70 to 95 ° C. for 2 to 8 hours at pH 6 to 7 and 70 to 130 rpm;
2) extracting the red algae primary extract obtained in step 1) for 2 to 9 hours at a temperature of 60 to 75 ° C .;
3) separating and purifying the red algae secondary extract obtained in step 2) and then sterilizing;
4) gelling the red algae secondary extract sterilized in step 3) at room temperature;
5) lyophilizing and grinding the gelled red algae secondary extract in step 4) to prepare a powder of 50-200 mesh; And
6) After the red algae powder obtained in step 5) and N-acetylpolyglucosamine are mixed, water is added to polymerize at pH 6-7 and 100-400 rpm at a temperature of 50-70 ° C. to extract red algae and Preparing a polymer of N-acetylpolyglucosamine; to Staphylococcus aureus , Escherichia coli , Candida albicans , and Pseudomonas aeruginosa It has an antimicrobial activity against water, and the water absorption capacity of the red algae extract and the polymer of N-acetylpolyglucosamine, characterized in that 1.58 ~ 2.8 times higher than the red algae extract when the absorption time is 10 seconds to 30 minutes. According to claim 9, Staphylococcus aureus , Escherichia coli , characterized in that the addition of the aromatic herbal oil at the time of mixing red algae powder and N-acetylpolyglucosamine in step 6) Red algae, which has antimicrobial activity against Candida albicans and Pseudomonas aeruginosa , and has a water absorption of 1.58 to 2.8 times higher than the red algae extract when the absorption time is 10 seconds to 30 minutes. A process for preparing an absorbent comprising an extract and a polymer of N-acetylpolyglucosamine.

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