Method for preparing novel processed ginseng or an extract thereof, the usually minute ginsenoside content of which is increased

1. A method for preparing a processed ginseng or processed ginseng extract having increased contents of ginsenosides Rg3 and Rh2, the method comprising the steps of:

(a) inoculating an Aspergillus niger strain into a medium composed of ginseng and wheat bran;

(b) culturing the strain of step (a) to produce a cultured material;

(c) purifying the cultured material of step (b) by ultrafiltration to produce a purified material using a membrane having a cutoff molecular weight of 100 KDa;

(d) separating an enzyme from the purified material of step (c), wherein the enzyme comprises β-glucosidase and α-rhamnosidase;

(e) adding the enzyme of step (d) to ginseng, red ginseng or a ginseng or red ginseng extract to obtain a mixture;

(f) fermenting the mixture of step (e) to produce a fermented material;

(g) separating the fermented material of step (f) to obtain a supernatant;

(h) concentrating the supernatant of step (g) to produce a concentrate;

(i) reacting the concentrate of step (h) with at least one organic acid selected from the group consisting of acetic acid, lactic acid, citric acid, malic acid and tartaric acid to produce a reaction product; and

(j) neutralizing, filtering, purifying, concentrating and drying the reaction product of step (i).

2. The method of claim 1 , wherein inoculation of the medium with Aspergillus niger in step (a) is performed, wherein the number of spores in an Aspergillus niger spore suspension is 5×10 5 spores per g of the medium and initial water content of the medium is maintained at 50-80%.

3. The method of claim 1 , wherein the β-glucosidase and α-rhamnosidase are present at a ratio (g/g) of 3:1 to 8:1.

4. The method of claim 1 , wherein the addition of the enzyme in step (e) is performed by adding the enzyme of step (d) in an amount of 5-20% based on the weight of the ginseng, the red ginseng or the ginseng or red ginseng extract.

5. The method of claim 1 , wherein the organic acid in step (i) is added to a 10% solution of the concentrate of step (h) in purified water in an amount of 1-50 wt % based on the weight of the concentrate solution, and the reaction in step (i) is carried out at a temperature of 40˜80° C. for 2-18 hours.

6. The method of claim 1 , wherein the fermentation in step (f) is carried out at a temperature of 25˜60° C. for 6-24 hours.