JPH1156344A - Production of mixed cultured product - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a culture filtrate in which algae are dissolved, having high content of CGF and having digested algae by subjecting microalgae and koji mold to mix culture under aerobic conditions. SOLUTION: Microalgae such as chlorella or Spirulina and koji mold such as Aspergillus oryjae are added to a medium to which as necessary, an alkali salt of lower fatty acid such as acetic acid, sugars, carbon source such as alcohol, nitrogen source such as nitrate, ammonium salt and a mineral such as phosphate, potassium salt, sodium salt, magnesium salt, calcium salt or iron salt are added and are subjected to mix culture under aerobic conditions to provide the objective culture filtrate in which algae are dissolved.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a mixed culture of algae and koji mold.

[0002]

2. Description of the Related Art At present, with the remarkable development of biotechnology, many useful substances such as various antibiotics and enzymes have been obtained by utilizing and culturing microorganisms.
However, most of the currently used methods of utilizing microorganisms only use substances obtained by pure culture of a single microorganism. Algae have hardly been used other than as a source of pigments such as chlorophyll and phycocyanin, in addition to using alga bodies as health foods. Algae are known from a wide variety of algae such as cyanobacteria, green algae, brown algae, red algae, diatoms, and flagellates that differ from single cells to multicells, and also differ in morphology and ecological In many cases, the growth rate is slow, and the cell wall is strong. Therefore, despite the fact that algae have a high ability to produce useful substances, their utilization is almost untapped.

[0003]

However, even if conventional methods are used to utilize the production capacity of algae with high useful substances, it takes a long time to grow the alga bodies, and the recovery of the alga bodies and the recovery of the alga bodies from the alga bodies are difficult. It requires a great deal of cost and time to extract useful substances. Algae were also used as S. cerevisiae. C. To use as P (microbial protein), only the algal cells must be cultured in clean water.

Further, microalgae are cultivated in large quantities, such as chlorella, but most microalgae, such as chlorella, except for spirulina, must be recovered by centrifugation, and the cost required for centrifugation is high. And the time is tremendous.

[0005] In order to utilize wastewater such as domestic wastewater and industrial wastewater, fermentation production of methane and the like by microorganisms is performed in some treatment facilities. Not popular. In addition, algae are cultured in sewage and the cells are transformed into S. algae. C. Although a method has been announced for use as P, it is hardly used as food or feed because it is cultured in sewage.

[0006]

SUMMARY OF THE INVENTION The present invention is directed to overcoming the above problems and relates to a method for producing a mixed culture in which algae are mixed and cultured with koji mold.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION Algae include, for example, green algae, cyanobacteria, alga, red algae, diatoms, and flagellates, and green algae are known to produce starch. Preferred examples of algae include chlorella, spirulina and the like.

As the koji mold, those used for brewing miso, soy sauce, sake and the like are preferable. For example, Aspergillus oryzae
e), the same awamori (A. awamori), the same nigger (A. niger), and the like.

[0009] Mixed culture of algae and Aspergillus can be performed by first culturing the algae and then inoculating the culture with the aspergillus and then inoculating the culture with the algae and Aspergillus from the beginning. Good.

Some algae can be cultured with autotrophs capable of performing photosynthesis, while others can be cultured with heterotrophs. Therefore, if necessary, a carbon source is added to the medium together with a nitrogen source and minerals. As the carbon source, for example, alkali salts of lower fatty acids such as acetic acid, saccharides, alcohols and the like are used. As a nitrogen source, for example, a nitrate or an ammonium salt is used, and as a mineral, a phosphate, a potassium salt, a sodium salt, a magnesium salt, a calcium salt, an iron salt, or the like is mixed and used.

The culture is carried out under aerobic conditions such as shaking culture and deep aeration culture.

When the algae and the koji mold are mixed and cultured, even if the algae are microalgae such as chlorella which are difficult to filter, the algae and the koji mold aggregate to form small spherules, which can be recovered by precipitation or flotation. And can be filtered off using gauze or other cloth.

On the other hand, when the mixed culture is further continued, the algae and the koji mold grow together at first, but the algae usually starts to dissolve after 3 to 4 days and eventually completely dissolves. If the koji mycelium is removed by filtration, a culture filtrate having a high CGF content can be obtained.

Since a mixed culture of an algae and a koji mold producing starch such as a green algae contains algae components and a saccharide produced from an enzyme of the koji mold, this can be subjected to alcohol fermentation. Fermentation is performed by inoculating a mixed culture with an alcohol-fermenting bacterium and culturing it under anaerobic conditions.
Examples of alcohol-fermenting bacteria include, for example, Saccharomyces cere.
viciae). Alcohol fermentation can be performed by a known method. As a nutrient source of algae, for example, sewage such as domestic wastewater can be used. Sewage is usually used as a nutrient source for cultivation after being subjected to a primary treatment such as an activated sludge method and a secondary treatment such as a spray filter method. Alcohol can be subjected to alcohol fermentation either by first culturing the algae alone and then inoculating the koji mold and then mixing and culturing the mixture, or by mixing and culturing the algae and the koji mold from the beginning. The mixed culture may be a culture in which algae are dissolved and koji mold remains. Thus, alcohol can be obtained from sewage and other waste by fermentation. In addition, the carbon dioxide gas generated thereby can be used as a carbon source in autotrophic algal culture.

[0015]

The present invention will be further described below with reference to examples and reference examples. Example (g) Medium composition: NaNO ₃ 2.0 MgSO ₄ .7H ₂ O 0.2 CaCl ₃ .2H ₂ O 0.05 FeSO ₄ .7H ₂ O 0.0025 K ₂ HPO ₄ 0.8 KH ₂ PO ₄ 0.2 Sodium acetate 10.0 The above components were dissolved in 1 liter of water, adjusted to pH 7.2 to 7.4, dispensed in 50 ml portions into a 500 ml Sakaguchi flask, and sterilized at 120 ° C. for 15 minutes. This was inoculated with Chlorella vulgaris Al-1 and miso seed koji Aspergillus oryzae or Aspergillus awamori.
), The chlorella and the koji grew together up to 3-4 days after the start of the culture, but thereafter the dissolution of the chlorella started rapidly, and the chlorella was completely dissolved after 5-6 days from the start of the culture. The culture was filtered to collect a white mycelium of koji and a slightly yellowish transparent culture filtrate. The CGF content of this culture was determined by a bioassay using lactic acid bacteria (
8-29074), and showed the same activity as the extract obtained by hot water extraction from Chlorella cells.

Reference Example 1 Chlorella bulgaris (Chlorella), a starch-producing chlorella, was added to a medium prepared in the same manner as in the Example.
vulgaris) Al-1 was inoculated with a loopful of chlorella taken from a preservation slope culture and shake-cultured at 30 ° C. for 4 days (130 reciprocations / minute). As a result, the growth of chlorella reached the upper limit. Add 50 ml of sterile culture solution, and add Aspergillus awamori for sake brewing.
gillus awamori), followed by shaking and culturing for 3 days. As a result, the chlorella cells were almost completely included in the koji hypha and formed a large number of aggregates having a diameter of about 5 mm. The alcohol yeast Saccharomyces cerevisiae
ciae) was inoculated and cultured at 30 ° C. for 4 days. As a result, production of carbon dioxide and alcohol was confirmed by an alcohol quantification method. The above yeast sucrose 15 g, asparagine _{0.3g, MgSO 4 · 7H 2 O} 0.2g, KH
₃ PO ₄ 0.5 g, yeast extract 0.1 g, water 100 ml
The medium was pre-cultured, and immediately before reaching the growth upper limit, the medium components were removed, and only the cells were used for inoculation.

Reference Example 2 Chlorella vulgaris Al-1 was cultured in the same manner as in the Example, and then Aspergillus awamori was inoculated and cultured with shaking for 3 days. The cells aggregated into small spheres and could be collected by filtration with gauze. In addition, Chlorella vulgaris E-25 having a soft cell wall is used as chlorella, and koji aspergillus soya for soy sauce is used as koji.
mixed culture using Soyae) and filtered with gauze to obtain dark green symbiotic cells. Further, Chlorella vulgaris E-25 was inoculated into the medium of the example, and at the same time Aspergillus awamori or Aspergillus soya, a seed koji for soy sauce, was added.
After shaking culture at 0 ° C. for 3 days, the same results as above were obtained. The dried product of the obtained cells is almost the same as the dried product of only Chlorella cells such as color tone and taste.

REFERENCE EXAMPLE 3 Chlorella vulgaris E was added to the medium described in the example, except that 20 g of glucose was used instead of sodium acetate.
-25 was inoculated with Aspergillus oryzae, mixed and cultured, and iron was added to the medium to test for resistance to iron.
As a control, a single culture of the above chlorella was used. The iron was added to the medium in the form of Na · Fe ethylenediaminetetraacetate. Table 1 shows the results.

[0019]

[Table 1] * The yield obtained by culturing in a medium without iron is 100.

As is clear from the above table, in the case of culturing with chlorella alone, the yield of cells was significantly reduced with an increase in the iron content of the medium, whereas in the case of mixed culture, it was 4,000 ppm. Even in a high-concentration iron-containing medium, the cell yield hardly decreased, and dark green cells were obtained.

[0021]

According to the present invention, a liquid culture having a high CGF content obtained by mixing and culturing algae with Aspergillus can be obtained.

Claims (2)

[Claims] 1. A method for producing a mixed culture, wherein a microalgae is mixed and cultured with koji mold under aerobic conditions to obtain a culture filtrate in which algae are dissolved. 2. The method according to claim 1, wherein the microalgae is chlorella.