KR20090018480A - Method for sterilization of silkworm powder - Google Patents

Abstract

A method for sterilizing the silkworm powder, the silkworm powder sterilized by the method, and a health food containing the silkworm powder are provided to improve the safety of sanitary. A method for sterilizing the silkworm powder comprises the steps of freeze-drying silkworm; and leaving the freeze-dried silkworm alone at a temperature and 80-120 deg.C and at a pressure of 1.2-1.5 atm for sterilization. Preferably the freeze-dried silkworm is pulverized into a silkworm powder for sterilization.

Description

Silkworm Sterilization Method {Method for Sterilization of Silkworm Powder}

The present invention relates to a method for sterilizing microorganisms by leaving lyophilized silkworm or silkworm powder at high temperature and high pressure, and to a method for producing hygienic safe silkworm or silkworm powder.

Medical records, including consent, report that silkworm pupa and silkworm cocoons are effective for diabetes. In addition, there has been a case of actually taking silkworms for the purpose of diabetic treatment, and research has been conducted on the method of pharmacological evaluation and formulation of silkworm powder.

To date, DNJ (1-deoxynojirimycin) is one of the most potent a-glucosidase inhibitors and is present in the highest proportion of water-soluble alkaloids in silkworms. Is considered as an indicator of hypoglycemic effects of health foods made with

Since the glycemic-boosting effect is expressed differently according to the manufacturing method of silkworm powder, the manufacturing method is very important.

In general, silkworms are one of the complete metamorphosis insects that have a lifelong process of waking up from eggs, making 4 cocoons, transforming them into silkworm pupa, then becoming moths, laying eggs, and dying in about 2 weeks. Physiological changes according to the growth stages of silkworm larvae are very large, and the difference in the level of substances including enzymes in the larvae before and after molting is known to be remarkable. It is very important to find out which stage of the growth stage of the silkworm larvae such a large change and which treatment to formulate silkworm powder.

Existing folk remedies use hot-air dried powders of silkworms at 5 days and 3 days or at the end of 5 years of age, which causes inactivation of various enzymes present in the silkworm body. Silkworms mainly contain mulberry leaf silkworm poultry, medium and small digestion fluid containing various enzymes, and blood. Among them, the medium-to-large liquid and the blood have a strong oxidizing power, and when contacted with air, they are easily oxidized and turn black and are inactivated. Therefore, the color of silkworm powder used in folk medicine is black powder.

As a result, anti-oxidation treatment is found to be the most important process for the formulation of silkworm powder, which is then freeze-dried while being stored in an cryogenic freezer.

According to Korean Patent No. 151,731, silkworms are treated with anti-oxidation and freeze-drying of silkworms to produce silkworm powder, which is an active ingredient of an anti-hyperglycemic agent. It is starting.

However, silkworm powder produced through hot air drying or lyophilization does not completely kill microorganisms such as Escherichia coli, so there is a problem in food safety when using silkworm powder as food. Therefore, in general, radiation is used for killing E. coli, but in this case, it remains a problem that it may have a harmful effect on the human body due to the residual radiation used.

  The present inventors have completed the present invention as a result of studying the sterilization method of microorganisms present in silkworm powder even without using radiation.

One object of the present invention is to provide a method for sterilizing silkworm or silkworm powder comprising the step of leaving the lyophilized silkworm or silkworm powder at high temperature and high pressure.

Another object of the present invention is to provide a health food comprising a silkworm or silkworm powder prepared by the above method.

In one aspect, the present invention

i) lyophilizing the biological silkworm;

ii) a method for sterilizing silkworms comprising the step of leaving the lyophilized silkworms at a temperature of 80 to 120 ° C. and 1.2 to 1.5 atmospheres.

As one specific embodiment, after the step i) relates to a method for sterilization of silkworms further comprising the step of grinding the silkworms into powder.

The silkworm of the present invention can be generally used silkworms of 4 to 5 years as silkworms collected from the production farm, but is not necessarily limited thereto.

The freeze-drying of the present invention is a method of rapidly freezing the moisture contained in silkworms and then subliming the moisture immediately under reduced pressure to dry it rapidly at an ultra low temperature of -30 to -80 ° C, and drying in a vacuum at the same temperature range. . Lyophilization should proceed for at least 25 hours, with 27-30 hours being most preferred.

After lyophilization, the silkworms may be ground to a powder using a grinder. The grinding method may use a variety of methods known in the art.

The lyophilized silkworm or silkworm powder is constant at a high pressure of 80 to 140 ° C, preferably 80 to 130 ° C, more preferably 80 to 120 ° C and 1.2 to 1.6 atm, preferably 1.2 to 1.5 atm. By leaving for at least 10 hours, preferably 10 minutes or more, more preferably 10 minutes to 2 hours, microorganisms such as Escherichia coli are killed to produce hygienically safe silkworms or silkworm powders.

The silkworm or silkworm powder sterilized and manufactured by the method of the present invention is hygienic and safe in the absence of E. coli compared to commercially available lyophilized or hot air dried silkworm powder (see Table 1), DNJ (1- Deoxynojirimycin) content is almost the same as lyophilized products, and superior to hot air dried products (see Table 2), so it can be manufactured in a safe state without compromising the efficacy of silkworms.

As another aspect, the present invention relates to a silkworm powder prepared by the above method and a health food comprising the same.

Silkworm powder having excellent hypoglycemic effect is hygienically safe as described above, so it can be used in various ways, such as drinks, food, etc. In particular, even if taken directly or diluted in water, there is no problem such as contamination by microorganisms. In addition, the silkworm powder of the present invention can be prepared in the form of tablets, capsules, granules, pills and the like can be applied as a health food.

The silkworm or silkworm powder prepared by the step of leaving the lyophilized silkworm or silkworm powder of the present invention in a high temperature and high pressure state is hygienic because there is no E. coli compared to commercially available lyophilized or hot-air dried silkworm powder It is safe, and is almost no difference from lyophilized product in DNJ (1-deoxynojirimycin) content, and can be useful when preparing silkworm powder because it is superior to hot air dried product.

In addition, silkworm powder prepared by the method of the present invention can be usefully used in the manufacture of various health foods and foods because of its excellent glycemic activity.

The following examples illustrate the present invention in more detail. These examples are only for illustrating the present invention, but the scope of the present invention is not limited to the following examples.

Example 1 Preparation of Silkworm Powder

The silkworms were harvested by laying the silkworms on the silkworm bed at 3 days and then frozen in an ultra-low temperature freezer (Sanyo, MDF-U2086S) at -40 ~ -45 ℃ and then powdered with a grinder (THOMAS, 3383L10). It was dried in a vacuum dryer (Bondiro, FD5508) at -60 ℃ for 27 to 30 hours. Sterilization for 40 minutes at 120 ℃, 1.5 atm in a high temperature, high pressure sterilizer (Sanyo, MLS-3780).

Example 2. Escherichia Coli Assay

1g weighed samples (freeze-dried sample, hot-air-dried sample, high-temperature, high-pressure sterilized sample) were put into a sterilized grinding container and ground. Distilled water was added thereto, mixed, and ground again. After standing for a while, 1 ml of supernatant was added to 100 ml of dilution water (a). 1 ml of diluted bacteria was added to 100 ml (b) and 9 ml (c) again. Inject 1 ml of the bacteria diluted with (a), (b) and (c) into a pertridish, and pour about 15 ml of sterilized broth (netrient agar, DFICO ™ Dehydrated Culture Media, BD-0001-17). After spreading well, it was left standing for a while. The inverted test vessel was inverted and incubated in a bacterial incubator for about 36 hours (incubator, Hanmi, E. coli Incubator, CI-1D-2). The number of colonies generated in the cultured medium was measured to determine the number of bacteria in the sample.

TABLE 1

No Processing condition E. coli detection ① Lyophilized Sample positivity ② Hot air dry sample positivity ③ High temperature, high pressure sterilization sample voice

Hot-air dried and lyophilized silkworm powder was positive in E. coli analysis test, but silkworm powder which had been sterilized by high temperature and high pressure sterilizer after lyophilization was negative in E. coli analysis test. Therefore, when using the high temperature, high pressure sterilization method of the present invention was confirmed that E. coli was killed.

Example 3. Experiment of Determining Content of DNJ (1-deoxynojirimycin)

A silkworm (freeze-dried sample, hot-air dried sample, high-temperature, high-pressure sterilized sample) was powdered, 0.1 g of which was taken, and then 10 ml of 0.5 N hydrochloric acid was added and stirred for 15 seconds. Supernatants were collected after centrifugation (21 days) at 21,690xg for 15 minutes (Hanil, Supra 21K). The supernatant was collected by repeating the extraction twice, and then diluted with 100 ml of water. 10 μl of the diluted solution was mixed with 10 μl of 0.4 M potassium borate buffer (Aldrich, pH 8.5) and 20 μl of 5 mM 9-flurenenylmethyl chloroformate (Fluka) acetonitrile and 20 at 20 ° C. After reacting for 10 minutes, 10 µl of excess 0.1 M glycine (Aldrich) was added to terminate the reaction. After addition of 950 μl of 0.1% aqueous acetic acid (Merck) solution, it was filtered through 0.2 μm injection filtration (Nalgene), and 10 μl was injected into HPLC. Column type used (Phenomenex Luna C18, 4.6 × 250㎜ ID 5㎛), solvent eluted with acetonitrile-0.1% acetic acid (1: 1, v / v), elution rate 1ml / min, detection FL3000 fluorescence A detector (exicitation 254 nm, emission 322 nm) and an analysis program used ChromQuest (Version 2.51), respectively.

TABLE 2

No Processing condition DNJ (1-deoxynojirimycin) content ① Lyophilized Sample 0.395% ② Lyophilized Sample 0.388% ③ Hot air dry sample 0.345% ④ High temperature, high pressure sterilization sample 0.373%

The change of DNJ (1-deoxynojirimycin) content of the second samples processed on the basis of DNJ (1-deoxynojirimycin) content (①, ② average value) of the lyophilized sample was about 11.9% of hot air drying and 4.7% of high-temperature / high pressure sterilizer. The decrease was shown.

Through this, the sterilization method of the present invention was found to be able to sterilize E. coli excellent while minimizing the reduction of DNJ (1-deoxynojirimycin) content.

The silkworm or silkworm powder prepared by the method of the present invention can be usefully used when producing silkworm powder because it is hygienic and safe because E. coli is not present compared to lyophilized or hot air dried silkworm powder commercially available.

In addition, silkworm powder prepared by the method of the present invention can be usefully used in the manufacture of various health foods and foods because of its excellent glycemic activity.

Claims (6)

i) lyophilizing the biological silkworm; And ii) sterilizing the silkworm comprising the step of leaving the lyophilized silkworm under a temperature of 80 to 120 ℃ and 1.2 to 1.5 atm. The method of claim 1, further comprising the step of pulverizing the silkworm after step i) to produce a silkworm powder. The method according to claim 1, wherein the lyophilization of step i) is frozen at a temperature of -40 ° C or lower and then dried in a vacuum state. The method of claim 1, wherein sterilizing the silkworm step ii) for 10 minutes to 2 hours. A sterile silkworm powder prepared by the method of any one of claims 1 to 4. Health food containing a silkworm powder of claim 5.