Optimization Of Liquid Fermentation Conditions For Ganoderma Lucidum And Vaccinium Spp And Analysis Of The Fermentation Product Activity

Ganoderma lucidum is rich in active substances and has the functions of scavenging free radicals,anti-oxidation,anti-aging,whitening and moisturizing,etc.At the present,the main utilized parts of Ganoderma lucidum are fruit bodies and spore powder.Wild fruiting bodies are scarce and the artificial cultivation period is too long,which make the fruiting bodies difficult to obtain and expensive in price.The utilization value of Ganoderma lucidum can be improved by liquid deep fermentation.In this study,we first used Ganoderma lucidum as the experimental material for optimization of liquid deep fermentation technologies,and then comparatively analyzed the biological activities of the fermentation products and fruiting body extracts.The results showed that the deep fermentation carried out on the malt-soaking culture medium at 30 ^oC for 6 days led to the best fermentation effects.The scavenging rates of DPPH free radicals,superoxide anions,hydroxyl radical and ABTS radicals of the fermentation broth were up to 94.05%,30.54%,54.43%and 82.55%,respectively;the broth has a reducing power of 0.63%and displayed a tyrosinase inhibition rate of 93.08%.When the active components in the fruiting bodies were extracted with ethanol under optimized conditions?80 ^oC,solid-liquid ratio 1:30?,the extract showed the highest scavenging rates of DPPH free radical?73.62%?,superoxide anions?7.44%?,hydroxyl radicals?45.43%?and ABTS radicals?68.23%?.Its reducing power was0.56%and tyrosinase inhibition rate was 76.65%.Comparatively,the antioxidant activity and tyrosinase inhibition rate of the deep fermentation broth prepared under the optimal conditions were 1.2-4.1times higher than those of the ethanol extract,and the total phenol,total sugar,and triterpene contents of the broth were also higher than those of the latter.The results of cytotoxicity test indicated that the IC₅₀ values of on cancer cells are lower than those on non-cancer cells,with a difference of at least 10 times,indicating that the cytotoxic effect of Ganoderma lucidum is highly specific.These results demonstrate that the deep fermentation can increase the utilization value of Ganoderma lucidum,and the resulting fermentation products have potential application in health food,pharmaceuticals and cosmetics.Blueberry?Vaccinium Spp?contains a variety of active ingredients and has multiple health functions such as anti-oxidation,delaying organism aging,enhancing memory and promoting sleep.Fresh blueberries have a short storage time,are not resistant to transportation,and have seasonal restrictions on production.In the second part of this study,blueberry juice was used as the fermentation raw material,and new blueberry products were prepared by deep fermentation in order to increase the utilization value of the blueberries.Acetic acid bacteria Shanghai brew 1.01,acetic acid bacteria SAS 1.41,lactic acid bacteria picp-2 and yeast ZLG-6 were used as the fermentation strains.The best combination of fermentation strains was determined through comparison of the fermentation effects of single strain and composite strains.The fermentation conditions for the best combination?picp-2+ZLG-6?were investigated and optimized,and the biological activities of the fermentation products were determined.The DPPH and superoxide anion clearance rates of the blueberry sample solution fermented by lactic acid bacteria picp-2 reached 98.40%and 41.38%,respectively.When the blueberry sample was single strain fermented by yeast ZLG-6,the resulting fermentation broth had a hydroxyl radical scavenging rate of 86.36%,ABTS scavenging rate90.32%.The fermentation effects of picp-2 and ZLG-6 were obviously better than those of acetic acid bacteria Shanghai brew 1.01 and acetic acid bacteria SAS 1.41.When we comparatively investigated the effects of different strain combinations on fermentation,we found that,compared with those of other strain combinations,the fermentation broth produced by the strain combination 6?picp-2+ZLG-6?had the best antioxidant capacity,the highest SOD content and total polyphenol content.The scavenging rates of DPPH free radicals,hydroxyl radical,superoxide anions and ABTS radicals of the broth reached 97.51%,85.68%,52.10%and 91.83%,respectively.The reducing power,SOD activity and total phenol content of the broth were 305.16 U/mL,305.16U/mL and 7.84 mg/mL,respectively.The optimal fermentation conditions of the strain combination 6 were:added skim milk content 1%,lactic acid bacteria picp-2 inoculation amount 1%,yeast ZLG-6 inoculation amount0.1%,fermentation temperature 20 ^oC,fermentation time 3-9 days.These results show that fermentation can increase the utilization value of blueberry;fermentation products not only can be applied in the development of blueberry drinks with high antioxidant capacity and unique flavor,but also can be used as antioxidant additives in health foods,medicines and cosmetics.