阅读说明：本技术 一种超富硒盐生杜氏藻制品及其制备方法和应用 (Super selenium-rich dunaliella salina product and preparation method and application thereof ) 是由 胡章立 郑怡鸿 祝华昌 李泽 姜发军 于 2021-07-08 设计创作，主要内容包括：本发明公开了一种超富硒盐生杜氏藻制品及其制备方法和应用,其中,一种超富硒盐生杜氏藻粉的制备方法,包括培育：将盐生杜氏藻在培养基中培养；无机硒的添加：在培养基中加入无机硒；成品获取：在无机硒加入后继续培养至少3天,收集并干燥即可。本发明可以采用盐生杜氏藻将无机硒转化为有机硒,制备过程简单易行；并且可以使盐生杜氏藻中有机硒的含量达到1000mg/kg以上,其中有机硒含量为总硒含量的80-99％,达到超富硒的标准；同时,制备得到的超富硒盐生杜氏藻制品可在常温状态下加入到食品、保健品和药品中,通过人体和动物的消化系统吸收利用。(The invention discloses a super selenium-enriched dunaliella salina product and a preparation method and application thereof, wherein the preparation method of the super selenium-enriched dunaliella salina powder comprises the following steps: culturing Dunaliella salina in a culture medium; adding inorganic selenium: adding inorganic selenium into the culture medium; obtaining a finished product: culturing for at least 3 days after adding inorganic selenium, collecting and drying. The invention can adopt Dunaliella salina to convert inorganic selenium into organic selenium, and the preparation process is simple and easy to implement; the content of organic selenium in the dunaliella salina can reach more than 1000mg/kg, wherein the content of the organic selenium is 80-99% of the total selenium content and reaches the standard of super selenium enrichment; meanwhile, the prepared super selenium-enriched dunaliella salina product can be added into food, health care products and medicines at normal temperature and absorbed and utilized by the digestive systems of human bodies and animals.)

1. An application of Dunaliella salina in converting inorganic selenium into organic selenium is provided.

2. A preparation method of super selenium-rich Dunaliella salina powder is characterized by comprising the following steps:

culturing: culturing Dunaliella salina in a culture medium;

adding inorganic selenium: adding inorganic selenium into the culture medium;

obtaining a finished product: culturing for at least 3 days after adding inorganic selenium, collecting and drying.

3. The method of claim 2, wherein the dunaliella salina is cultured in the medium for at least 6 days before adding inorganic selenium to the medium.

4. The method according to claim 3, wherein the total culture time of the Dunaliella salina in the culture medium is 9-15 days.

5. The process of claim 4, wherein the dunaliella salina is incubated in the medium for 9 days before the addition of inorganic selenium; the total cultivation time of Dunaliella salina in the culture medium is 15 days.

6. The process according to any one of claims 2 to 5, wherein the inorganic selenium is selenite or/and selenate, preferably sodium selenite;

the inoculation amount of the dunaliella salina is 5-10 multiplied by 10⁵cell/mL; the final concentration of sodium selenite in the culture medium is 8-64 mg/L.

7. The method according to claim 6, wherein the final concentration of sodium selenite in the culture medium is 8-16 mg/L.

8. The method according to any one of claims 2 to 7, wherein the medium consists of:

H₃BO₃：9.28mg/L，CoCl₂·6H₂O：0.05mg/L，ZnCl₂：0.11mg/L，MnCl₂·4H₂O：1.98mg/L，Na₂MoO₄：0.49mg/L，NaVO₃：0.24mg/L，CuCl₂·6H₂O：0.05mg/L，MgSO₄·7H₂O：1.23g/L，KCl：0.2g/L，CaCl₂·2H₂O：0.044g/L，KNO₃：0.2～0.8g/L，KH₂PO：0.014g/L，FeCl₃·6H₂O：0.0005g/L，Na₂EDTA：0.074g/L，NaHCO₃：2～4g/L，NaCl：58.44～116.88g/L。

9. a Dunaliella salina product, which is characterized by comprising the super selenium-enriched Dunaliella salina powder prepared by the preparation method of any one of claims 2 to 8.

10. The use of a dunaliella salina product according to claim 9 in a food, health product or pharmaceutical product.

Technical Field

The invention relates to the field of microalgae, in particular to a super selenium-enriched dunaliella salina product and a preparation method and application thereof.

Background

Selenium exists in the living body mainly in the form of organic selenium, and exerts its effect by selenase. Some lower organisms, including microalgae and bacteria, as well as mammals, birds and fish, selenium is an essential micronutrient and selenocysteine (SeCys) is a part of the selenoprotein active site as the active group. Selenium is a component of over 30 kinds of human selenases, which participate in many important metabolic pathways including thyroid hormone metabolism, immune defense system, antioxidant defense and reproductive function, and in important biological functions such as anticancer, biomembrane protection, anti-aging, free radical scavenging, and immunity enhancement. The world health organization recommends that the daily selenium requirement for adults is about 40 mug, and people usually supplement selenium by some medicines or selenium-rich foods, however most medicines are inorganic selenium, are difficult to absorb and have higher toxicity than organic selenium in foods.

In the prior art, green microalgae preferentially bind selenium in selenite and selenate to selenoprotein and seleno-amino acids, particularly selenomethionine (SeMet) and selenocysteine (SeCys). At present, algae strains for enriching selenium by using microalgae comprise chlamydomonas reinhardtii, haematococcus pluvialis, chlorella vulgaris, scenedesmus tetracaudatus and the like, the enrichment amount of the algae is 140-500 mg/kg dry weight, but the selenium-containing critical standard of 1000-15000 mg/kg of super selenium-enriched plants is not reached.

Dunaliella salina belongs to Chlorophyta (Chlorophyta), Chlorophyceae (Chlorophyceae), Volvocales (Volvocales), Dunaliella salina (Dunaliella), can grow in 0.05-5.5 mol/L sodium chloride (NaCl) environment, and can accumulate abundant glycerol in cells. In addition, the dunaliella salina is rich in carotenoid, the content of common wild type is usually 3-5%, and the content can reach 10% after breeding and optimizing culture conditions, and the content is the highest in known organisms. There is no disclosure in the prior art that dunaliella salina can be used to bind the selenium element in selenite and selenate to selenoprotein and seleno-amino acids to form organic selenium.

Disclosure of Invention

Therefore, the invention aims to provide a super selenium-enriched dunaliella salina product and a preparation method and application thereof, inorganic selenium can be converted into organic selenium by using the dunaliella salina, the content of the organic selenium in the dunaliella salina can reach more than 1000mg/kg, wherein the content of the organic selenium is 80-99% of the total selenium content, and the standard of super selenium enrichment is achieved; the prepared super selenium-enriched dunaliella salina product can be added into food, health products and medicines at normal temperature and absorbed and utilized by the digestive systems of human bodies and animals.

An application of Dunaliella salina in converting inorganic selenium into organic selenium is provided.

A method for preparing super selenium-rich Dunaliella salina powder comprises:

culturing: culturing Dunaliella salina in a culture medium;

adding inorganic selenium: adding inorganic selenium into the culture medium; the inorganic selenium can be added before the dunaliella salina is inoculated, or in the process of cultivating the dunaliella salina;

obtaining a finished product: culturing for at least 3 days after adding inorganic selenium, collecting and drying.

After the Dunaliella salina is cultured in the culture medium for at least 6 days, inorganic selenium is added into the culture medium.

The total culture time of the dunaliella salina in the culture medium is 9-15 days.

Before the addition of inorganic selenium, the culture time of the dunaliella salina in the culture medium is 9 days; the total cultivation time of Dunaliella salina in the culture medium is 15 days.

The inorganic selenium is selenite or/and selenate, preferably sodium selenite;

the inoculation amount of the Dunaliella salina is 5-10 multiplied by 10⁵cell/mL; the final concentration of sodium selenite in the culture medium is 8-64 mg/L.

The final concentration of sodium selenite in the culture medium is 8-16 mg/L.

The culture medium comprises the following components:

H₃BO₃：9.28mg/L，CoCl₂·6H₂O：0.05mg/L，ZnCl₂：0.11mg/L，MnCl₂·4H₂O：1.98mg/L，Na₂MoO₄：0.49mg/L，NaVO₃：0.24mg/L，CuCl₂·6H₂O：0.05mg/L，MgSO₄·7H₂O：1.23g/L，KCl：0.2g/L，CaCl₂·2H₂O：0.044g/L，KNO₃：0.2～0.8g/L，KH₂PO：0.014g/L，FeCl₃·6H₂O：0.0005g/L，Na₂EDTA：0.074g/L，NaHCO₃：2～4g/L，NaCl：58.44～116.88g/L。

a Dunaliella salina product contains the super selenium-rich Dunaliella salina powder prepared by the preparation method.

An application of Dunaliella salina product in food, health product or medicine is provided.

The technical scheme of the invention has the following advantages:

1. the invention provides an application of dunaliella salina in conversion of inorganic selenium into organic selenium, wherein the dunaliella salina can be used for converting the inorganic selenium into the organic selenium, and the dunaliella salina can also accumulate beta-carotene.

2. The invention provides a preparation method of super selenium-rich dunaliella salina powder, which is used for producing a super selenium-rich dunaliella salina product by efficiently enriching selenium in the dunaliella salina, so that the content of total selenide in the dunaliella salina can reach 10-15000 mg/kg, wherein the content of organic selenium is 80-99%; meanwhile, the organic selenium content can reach over 1000mg/kg through the optimization of the culture conditions, the critical standard of the super selenium enrichment is met, and the preparation process is simple and easy to implement.

3. The invention provides a dunaliella salina product, which comprises super selenium-rich dunaliella salina powder simultaneously containing organic selenium and beta-carotene; the organic selenium and the beta-carotene have synergistic effect, so that the dunaliella salina has super oxidation resistance, and the dunaliella salina can be protected by taking the dunaliella salina as a carrier; therefore, the dunaliella salina product can be added into other products at normal temperature and absorbed and utilized by the digestive systems of human bodies and animals.

4. The invention provides an application of a dunaliella salina product in food, health care products or medicines; the dunaliella salina product simultaneously contains beta-carrot and organic selenium, cis-isomer of beta-carotene can not be chemically synthesized, and the cis-isomer is proved to have stronger effects on cardiovascular disease resistance and oxidation resistance than trans-isomer; the organic selenium and the beta-carotene in the dunaliella salina are effective components in a plurality of foods, health care products and medicines, so the method for producing the super selenium-enriched dunaliella salina product by utilizing the high-efficiency selenium enrichment of the dunaliella salina has important application value in the preparation of the foods, the health care products and the medicines, and can be effectively applied to the foods, the health care products or the medicines.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, and it is obvious that the drawings in the following description are some embodiments of the present invention, and other drawings can be obtained by those skilled in the art without creative efforts.

FIG. 1 is a graph showing the growth of Dunaliella salina in example 1 of the present invention;

FIG. 2 is a graph showing the growth of Dunaliella salina in example 2 of the present invention;

FIG. 3 is a graph showing the growth of Dunaliella salina in example 3 of the present invention;

FIG. 4 is a graph showing the maximum photosynthesis efficiency of Dunaliella salina in example 1 of the present invention;

FIG. 5 is a graph showing the actual photosynthesis efficiency of Dunaliella salina in example 1 of the present invention;

FIG. 6 is a graph showing the maximum photosynthesis efficiency of Dunaliella salina in example 2 of the present invention;

FIG. 7 is a graph showing the actual photosynthesis efficiency of Dunaliella salina in example 2 of the present invention;

FIG. 8 is a graph showing the maximum photosynthesis efficiency of Dunaliella salina in example 3 of the present invention;

FIG. 9 is a graph showing the actual photosynthesis efficiency of Dunaliella salina in example 3 of the present invention;

FIG. 10 is a bar graph of the enrichment of total selenium in Dunaliella salina in example 1 of the present invention;

FIG. 11 is a bar graph of the enrichment of total selenium in Dunaliella salina in example 2 of the present invention;

FIG. 12 is a bar graph of the enrichment of organoselenium and total selenium in Dunaliella salina of the present invention in example 3.

Detailed Description

The Dunaliella salina used in the following examples of the present invention was obtained from the aquatic institute of Chinese academy of sciences, and was characterized by strong tolerance to inorganic selenium, high selenoprotein and carotenoid content, and rapid growth of Dunaliella salina FCHB-435.

Example 1

A method for preparing super selenium-rich Dunaliella salina powder comprises:

a) culturing Dunaliella salina in culture medium at 25 + -0.5 deg.C under light intensity of 50 μmol · m^-2s^-1Inoculation amount of 5X 10⁵cell/mL; the growth of the dunaliella salina is divided into an inoculation stage, a vegetative growth stage and a selenium conversion stage.

The culture medium comprises the following components: h₃BO₃：9.28mg/L，CoCl₂·6H₂O：0.05mg/L，ZnCl₂：0.11mg/L，MnCl₂·4H₂O：1.98mg/L，Na₂MoO₄：0.49mg/L，NaVO₃：0.24mg/L，CuCl₂·6H₂O：0.05mg/L，MgSO₄·7H₂O：1.23g/L，KCl：0.2g/L，CaCl₂·2H₂O：0.044g/L，KNO₃：0.5g/L，KH₂PO：0.014g/L，FeCl₃·6H₂O：0.0005g/L，Na₂EDTA：0.074g/L，NaHCO₃: 2.1g/L, NaCl: 87.7 g/L. The culture medium is added with NaHCO₃The former pH was 7.5.

The volume of each culture medium is set to be 150mL, and sodium selenite can be added into the culture medium to control the concentration of the sodium selenite in the whole system to be 0.01-8mg/L, or the sodium selenite is not added. In this example, sodium selenite was not added.

b) Selecting 4 culture media, and adding sodium selenite into the 4 culture media on the first day of culture to ensure that the final concentrations of the sodium selenite in the culture system are respectively 8mg/L, 16mg/L, 32mg/L and 64 mg/L; the final concentration refers to the concentration of untransformed sodium selenite in the culture system.

c) The culture was carried out for a total of 21 days, shaking each day in the morning and afternoon.

d) Collecting the cultured super selenium-rich Dunaliella salina, and freeze-drying to obtain super selenium-rich Dunaliella salina powder.

Example 2

A method for preparing super selenium-rich Dunaliella salina powder comprises:

a) culturing Dunaliella salina in culture medium at 25 + -0.5 deg.C under light intensity of 50 μmol · m^-2s^-1Inoculation amount of 5X 10⁵cell/mL; the growth of the dunaliella salina is divided into an inoculation stage, a vegetative growth stage and a selenium conversion stage.

The culture medium comprises the following components: h₃BO₃：9.28mg/L，CoCl₂·6H₂O：0.05mg/L，ZnCl₂：0.11mg/L，MnCl₂·4H₂O：1.98mg/L，Na₂MoO₄：0.49mg/L，NaVO₃：0.24mg/L，CuCl₂·6H₂O：0.05mg/L，MgSO₄·7H₂O：1.23g/L，KCl：0.2g/L，CaCl₂·2H₂O：0.044g/L，KNO₃：0.5g/L，KH₂PO：0.014g/L，FeCl₃·6H₂O：0.0005g/L，Na₂EDTA：0.074g/L，NaHCO₃: 2.1g/L, NaCl: 87.7 g/L. The culture medium is added with NaHCO₃The former pH was 7.5.

The volume of each culture medium is set to be 150mL, and sodium selenite can be added into the culture medium to control the concentration of the sodium selenite in the whole system to be 0.01-8mg/L, or the sodium selenite is not added. In this example, sodium selenite was not added.

b) Selecting 4 culture media, adding selenium for three times, and adding sodium selenite to the 4 culture media respectively on 3 rd, 6 th and 9 th days of culture to make the final concentration of sodium selenite in the culture system respectively 8mg/L, 16mg/L, 32mg/L and 64 mg/L; the final concentration refers to the concentration of untransformed sodium selenite in the culture system.

c) The culture was carried out for a total of 21 days, shaking each day in the morning and afternoon.

d) Collecting the cultured super selenium-rich Dunaliella salina, and freeze-drying to obtain super selenium-rich Dunaliella salina powder.

Example 3

A method for preparing super selenium-rich Dunaliella salina powder comprises:

a) culturing Dunaliella salina in culture medium at 25 + -0.5 deg.C under light intensity of 50 μmol · m^-2s^-1Inoculation amount of 5X 10⁵cell/mL; the growth of the dunaliella salina is divided into an inoculation stage, a vegetative growth stage and a selenium conversion stage.

The culture medium comprises the following components: h₃BO₃：9.28mg/L，CoCl₂·6H₂O：0.05mg/L，ZnCl₂：0.11mg/L，MnCl₂·4H₂O：1.98mg/L，Na₂MoO₄：0.49mg/L，NaVO₃：0.24mg/L，CuCl₂·6H₂O：0.05mg/L，MgSO₄·7H₂O：1.23g/L，KCl：0.2g/L，CaCl₂·2H₂O：0.044g/L，KNO₃：0.5g/L，KH₂PO：0.014g/L，FeCl₃·6H₂O：0.0005g/L，Na₂EDTA：0.074g/L，NaHCO₃: 2.1g/L, NaCl: 87.7 g/L. The culture medium is added with NaHCO₃The former pH was 7.5.

The volume of each culture medium is set to be 150mL, and sodium selenite can be added into the culture medium to control the concentration of the sodium selenite in the whole system to be 0.01-8mg/L, or the sodium selenite is not added. In this example, sodium selenite was not added.

b) Selecting 4 culture media, and adding selenium at logarithmic phase (day 9), namely adding sodium selenite to the 4 culture media at logarithmic phase respectively to make the final concentration of sodium selenite in the culture system respectively 8mg/L, 16mg/L, 32mg/L and 64 mg/L; the final concentration refers to the concentration of untransformed sodium selenite in the culture system.

c) The culture was carried out for a total of 21 days, shaking each day in the morning and afternoon.

d) Collecting the cultured super selenium-rich Dunaliella salina, and freeze-drying to obtain super selenium-rich Dunaliella salina powder.

Example 4

A method for preparing super selenium-rich Dunaliella salina powder comprises:

a) culturing Dunaliella salina in culture medium at 25 + -0.5 deg.C under light intensity of 40 μmol · m^-2s^-1Inoculation amount of 5X 10⁵cell/mL。

The culture medium comprises the following components: h₃BO₃：9.28mg/L，CoCl₂·6H₂O：0.05mg/L，ZnCl₂：0.11mg/L，MnCl₂·4H₂O：1.98mg/L，Na₂MoO₄：0.49mg/L，NaVO₃：0.24mg/L，CuCl₂·6H₂O：0.05mg/L，MgSO₄·7H₂O：1.23g/L，KCl：0.2g/L，CaCl₂·2H₂O：0.044g/L，KNO₃：0.8g/L，KH₂PO：0.014g/L，FeCl₃·6H₂O：0.0005g/L，Na₂EDTA：0.074g/L，NaHCO₃: 3.1g/L, NaCl: 60.7 g/L. The culture medium is added with NaHCO₃The former pH was 7.0.

The volume of the medium was set to 150 mL.

b) Selenium was added at logarithmic phase (day 9) to give a final concentration of 16mg/L sodium selenite in the culture system.

c) The culture was carried out for a total of 21 days, shaking each day in the morning and afternoon.

d) Collecting the cultured super selenium-rich Dunaliella salina, and freeze-drying to obtain super selenium-rich Dunaliella salina powder.

Example 5

A method for preparing super selenium-rich Dunaliella salina powder comprises:

a) culturing Dunaliella salina in culture medium at 25 + -0.5 deg.C under light intensity of 60 μmol · m^-2s^-1The inoculation amount is 10 multiplied by 10⁵cell/mL。

The culture medium comprises the following components: h₃BO₃：9.28mg/L，CoCl₂·6H₂O：0.05mg/L，ZnCl₂：0.11mg/L，MnCl₂·4H₂O：1.98mg/L，Na₂MoO₄：0.49mg/L，NaVO₃：0.24mg/L，CuCl₂·6H₂O：0.05mg/L，MgSO₄·7H₂O：1.23g/L，KCl：0.2g/L，CaCl₂·2H₂O：0.044g/L，KNO₃：0.2g/L，KH₂PO：0.014g/L，FeCl₃·6H₂O：0.0005g/L，Na₂EDTA：0.074g/L，NaHCO₃: 3.8g/L, NaCl: 110.7 g/L. The culture medium is added with NaHCO₃The former pH was 8.0.

The volume of the medium was set to 150 mL.

b) Selenium was added at logarithmic phase (day 9) to give a final concentration of 16mg/L sodium selenite in the culture system.

c) The culture was carried out for a total of 21 days, shaking each day in the morning and afternoon.

d) Collecting the cultured super selenium-rich Dunaliella salina, and freeze-drying to obtain super selenium-rich Dunaliella salina powder.

Example 6

A Dunaliella salina product used in food comprises: the selenium-enriched Dunaliella salina powder prepared in the embodiment is crushed according to the requirement of food preparation, the crushed powder is added into bread and noodles or milk powder and coffee, the mixture is uniformly mixed, and the selenium-enriched food can be prepared according to a conventional method.

Example 7

The application of Dunaliella salina product in health products comprises: the preparation method comprises the steps of preparing the super selenium-enriched Dunaliella salina powder in the embodiment, carrying out nano-crushing according to the manufacturing requirement of the health care product, and adding the crushed powder into tablet auxiliary materials such as cellulose, for example: adopting algae powder: the auxiliary material is prepared into tablets or capsules according to the proportion of 1:3, and then the health-care product of the high-selenoprotein dunaliella salina is obtained.

Example 8

A Dunaliella salina product used in medicine comprises: the super selenium-enriched Dunaliella salina powder prepared in the embodiment is used, the content of beta-carotene and selenoprotein is detected by using high pressure liquid chromatography and hydride atomic fluorescence spectrometry, and the algae powder can be directly used for preparing medicines or can be mixed with other components to prepare medicines. Or extracting effective components such as selenoprotein and astaxanthin in algae powder, and making into medicine containing high selenoprotein Dunaliella salina, such as anticancer medicine and antiviral medicine.

Experimental example 1

The cells of Dunaliella salina prepared in examples 1-3 were counted and growth curves were plotted, and the results are shown in FIGS. 1-3.

The maximum photosynthesis efficiency and the actual photosynthesis efficiency of the dunaliella salina cells prepared in examples 1 to 3 were measured at the same time, and efficiency curves were drawn, and the results are shown in fig. 4 to 9.

As can be seen from fig. 1 to 3: the cell number of the algae is basically consistent with that of a control group without selenium when the concentration of the sodium selenite is 8-64mg/L and 9 days before culture, which shows that the sodium selenite has no influence on the growth of the dunaliella salina in the early growth stage and the concentration of 8-64 mg/L; after 9 days, when the concentration of sodium selenite is increased to 16mg/L, the number of the Dunaliella salina cells is reduced, the cell growth is inhibited, the inhibition effect is enhanced along with the increase of the selenium concentration, and when the concentration of sodium selenite is increased to 64mg/L, the maximum concentration of the algal cells is reduced to 10⁷Individual cells/mL or less.

As can be seen from fig. 4 to 9: as can be seen from the photosynthetic efficiency, 16mg/L of sodium selenite treatment showed a decrease after 15 days of culture. It can be concluded that when the final concentration of sodium selenite in the culture system is 16mg/L, the optimal balance can be obtained between obtaining more organic selenium and finally obtaining more Duchenne cells.

Experimental example 2

Samples of the sodium selenite treated algal cells of example 1-example 5 were collected by centrifugation at different concentrations, vacuum freeze-dried for 24h, and 0.0100g of the samples were weighed and added with 10mL ddH₂In O, heating to room temperature by using a temperature-controllable electric heating furnaceBoiling for 10 min; after cooling, the flask was transferred to a 10mL volumetric flask for constant volume. Shaking, filtering, collecting filtrate 7mL, adding 10mL cyclohexane for extraction, transferring the water phase into a 15mL centrifuge tube, and measuring inorganic selenium content by ICP-MS.

Weighing 0.0100g, placing into a digestion tank, adding 3mL of 95% concentrated nitric acid and 1mL of 20% hydrogen peroxide solution (ratio is 3:1), digesting in a microwave digestion instrument, pouring the digested sample into a beaker, keeping boiling to remove excessive concentrated nitric acid, ddH₂O is metered to 10mL, and the total selenium content is determined by ICP-MS.

The content of organic selenium is total selenium content-inorganic selenium content.

The detection results are shown in FIGS. 10 to 12; as can be seen from fig. 10 to 12: when the final concentration of sodium selenite in the culture system is 8-64mg/L, the enrichment amount of organic selenium and total selenium in the algae increases along with the increase of selenium concentration; but according to physiological and biochemical data, the dunaliella salina can be less affected under the condition of enriching more selenium under the condition of culturing in 16mg/L sodium selenite; therefore, when the final concentration of sodium selenite in the culture system is 16mg/L, the content of the organic selenium component in the algae cells reaches 1262.67 mug/g, and the content of the organic selenium reaches 1112.07 mug/g, so that the best effect is achieved. In addition, when the final concentration of the sodium selenite is 16mg/L, the content of the organic selenium component obtained in the examples 4 and 5 is not greatly different from that of the organic selenium component obtained in the example 3 when the final concentration is 16mg/L, and the content is respectively as follows: 1087.78 mug/g and 1214.41 mug/g, which can reach over 1000 mug/g.

It should be understood that the above examples are only for clarity of illustration and are not intended to limit the embodiments. Other variations and modifications will be apparent to persons skilled in the art in light of the above description. And are neither required nor exhaustive of all embodiments. And obvious variations or modifications therefrom are within the scope of the invention.