Bioconversion,health benefits,and application of ginseng and red ginseng in dairy products

Ginseng and red ginseng are popular as functional foods in Asian countries such as Korea, Japan, and China. They possess various pharmacologic effects, including antioxidant, anti-inflammatory, anti-cancer, anti-obesity, and anti-viral activities. Ginsenosides are a class of pharmacologically active components in ginseng and red ginseng. Major ginsenosides are converted to minor ginsenosides, which have better bioavailability and cellular uptake, by microorganisms and enzymes. Studies have shown that ginseng and red ginseng can affect the physicochemical and sensory properties, ginsenosides content, and functional properties of dairy products. In addition, lactic acid bacteria in dairy products can convert into minor ginsenosides and ginseng and red ginseng improve functionality of products. This review will discuss the characteristics of ginseng and red ginseng, and their bioconversion, functionality, and application in dairy products.     

Anti‐inflammatory and cytotoxic effects of ginseng extract bioconverted by Leuconostoc mesenteroides KCCM 12010P isolated from kimchi

A bioconversion technique using microorganisms has been applied to ginseng to increase content of bioactive ginsenoside and biofunctionality such as anticancer, anti‐obesity and antioxidant activities. The objective of this study was to screen lactic acid bacteria for bioconversion of ginsenosides and to evaluate anti‐inflammatory and cytotoxic effects of bioconverted ginseng extract. Strains isolated from kimchi were screened for their β‐glucosidase activities using esculin agar. Selected strain was identified based on 16S rRNA sequencing and carbohydrate fermentation. During ginseng fermentation, viable cell number and pH were determined. Bioconverted ginsenosides were analysed by HPLC. Anti‐inflammatory effects were evaluated using RAW 264.7 cells, and cytotoxic effects were determined by MTT assay. Among 166 isolates screened, Leuconostoc mesenteroides was selected for ginseng bioconversion, as it showed a higher β‐glucosidase activity and viable cell number than any of the other tested strains. After fermentation for 2 days, viable cell number was 8.8 log CFU mL^?1 and final pH was 4.8. Ginsenoside Rb₂ was bioconverted into ginsenoside Rg₃ (Rb₂ → Rd → Rg₃) by L. mesenteroides. The nitric oxide contents of 2‐day‐fermented extract decreased by as much as 25%, compared to a non‐fermented extract. The cell viabilities of HepG2, HT‐29, HeLa and LoVo treated with fermented ginseng extract also decreased by 49.7%, 20.2%, 21.0% and 8.7%, respectively, compared to those of control cells treated with non‐fermented extract. Ginseng extract bioconverted by L. mesenteroides showed anti‐inflammatory and anticancer effects. Therefore, bioconverted ginseng extract might have applications in the pharmaceutical and/or functional food industry.     

Use of Lactobacillus rossiae DC05 for bioconversion of the major ginsenosides Rb1 and Re into the pharmacologically active ginsenosides C-K and Rg2

Rb1 and Re are the major ginsenosides in protopanaxadiol and protopanaxatriol with contents of 38.89 and 13.34%, respectively. β-Glucosidase-producing food grade Lactobacillus rossiae DC05 was isolated from kimchi using esculin-MRS agar and an enzyme of L. rossiae DC05 was used for bioconversion of the major ginsenosides Rb1 and Re. Strain DC05 showed strong activity in converting ginsenosides Rb1 and Re into the minor ginsenosides compound-K and Rg2, respectively. Within 4 days, 100% of ginsenoside Rb1 was decomposed and converted into C-K, while 85% of Re was decomposed and converted into Rg2 after 6 days of incubation. The biosynthesis rate of ginsenoside C-K was 72.88%, and the biosynthesis rate of Rg2 was 53.94%. Strain DC05 hydrolyzed ginsenosides Rb1 and Re along the pathway Rb1→Rd→F2→CK and the pathway Re→Rg2, respectively. The optimum temperature and pH of the enzyme were 30°C and 7.0, respectively.     

Effect of crude microbial enzyme pretreatment on the liberation of biological compounds and antioxidant activity of red ginseng extract

To improve the quality of red ginseng extract, the effects of crude microbial enzyme pretreatment on the liberation of biological compounds and the antioxidant activity of the extract were studied. The total ginsenoside contents in red ginseng extract pretreated with and without crude microbial enzyme were 199 and 186μg/mL, respectively. More specifically, ginsenosides with the protopanaxadiol type of aglycone moieties showed significant increases (about 10%), while the protopanaxatriol type ginsenosides were hardly changed. Ginsenosides are thermally unstable, as they may degrade during thermal extraction above 70°C, and protopanaxatriol type ginsenosides are more susceptible than protopanaxadiol type. The contents of soluble solid, reducing sugars, polyphenolic compounds, and recovery of the enzymatic-pretreated group were increased 17, 51, 10, and 17%, respectively, compared with control. Additionally, the enzymatic-pretreated red ginseng extract showed significantly higher antioxidant activity and free radical scavenging ability than control.     

人参皂苷抗肿瘤活性与机制研究进展

人参是一种重要的食药同源植物,具有抗肿瘤、抗炎、抗疲劳及提高免疫力等多种生理功能。人参皂苷是人参中最重要的活性成分,体内及体外实验证实人参皂苷具有显著的抗肿瘤活性,其中人参皂苷Rg3已经用于肿瘤患者辅助治疗的单体药物。研究表明人参皂苷的抗肿瘤活性是通过不同途径实现的,包括抑制肿瘤细胞增殖、诱导肿瘤细胞凋亡、抑制肿瘤细胞侵袭和转移、阻断肿瘤血管生成、增强机体免疫系统、抗氧化应激以及与化疗药物协同作用等。本文针对人参皂苷抗肿瘤作用途径进行综述,为人参抗肿瘤功能性食品的开发提供理论基础。     

β-Glycosidase-assisted bioconversion of ginsenosides in purified crude saponin and extracts from red ginseng (Panax ginseng C. A. Meyer)

Major ginsenosides in ginseng (Panax ginseng) and its products are highly glycosylated, hence poorly absorbed in the gastrointestinal tract. β-Glycosidase-assisted deglycosylation of pure ginsenosides was peformed to study bioconversion mechanisms. Ginsenoside standard compounds, crude saponin, and red ginseng extracts were incubated with β-glycosidase (0.05% w/v, 55°C). β-Glycosidase has a broad specificity for β-glycosidic bonds, hydrolyzing the β-(1→6), α-(1→6), and α-(1→2) glycosidic linkages. The final metabolite of protopanaxadiol ginsenosides was Rg3 while the metabolite of protopanaxatriol ginsenosides was Rh1. β-Glycosidase treatment of red ginseng extracts resulted in a decrease in the amounts of Rb1, Rc, Re, and Rg2 after 24 h, whereas levels of the less glycosylated Rd, Rb1, Rg, Rg3, Rg1, and Rh1 forms increased. When crude saponin was incubated with β-glycosidase for 24 h, levels of Rb1, Rc, Re, and Rg1 decreased while levels of Rd, Rg3, and Rh1 increased as deglycosylated ginsenosides.     

Improved production of ginsenosides in suspension cultures of ginseng by medium replenishment strategy

The objective of this study was to improve the accumulation of ginsenosides by the adventitious root cultures of ginseng, which are important secondary metabolites with pharmaceutical applications. The adventitious roots were cultured in bioreactors for 50 d using 1.5-strength Murashige and Skoog (MS) medium supplemented with 10 mg/l indole acetic acid and 75 g/l sucrose. Kinetic studies of the nutrient composition of the spent medium revealed the gradual depletion of various inorganic nutrients and sugars. Cultures were supplied with fresh nutrient medium (medium exchange or replenishment with 0.75- and 1.0-strength MS medium) after 10 and 20 d of culture initiation to fulfill the nutritional requirements of adventitious roots. Medium replenishment strategy (with 1.0-strength MS medium after 20 d of culture) significantly improved the growth of adventitious roots and the biosynthesis of ginsenosides by the adventitious roots. This work is useful for the large-scale cultivation of adventitious roots for the production of ginsenosides.     

Transformation of ginsenoside-rich fraction isolated from ginseng (<Emphasis Type="Italic">Panax ginseng</Emphasis>) leaves induces compound K

To develop the new physiologically active materials from ginseng (Panax ginseng C.A. Meyer) leaves, the ginsenoside-rich fraction (GL-1) was isolated and transformed into highly absorbable metabolites in the gastrointestinal (GI) tract. To transform the ginsenosides in GL-1 into deglycosylated ginsenosides, GL-1 was treated with organic acids (0.1 and 1% lactic and acetic acid solutions) and fermented with isolated strains (P1-P4, and M3) from red ginseng extract for 7 days. The treatment of 0.1% lactic acid of GL-1 induced the highest transforms of partially-deglycosylated ginsenosides such as Mc, F2, and Rg3 (intermediate metabolites). On the other hand, Compound K (Compd K, final metabolite) contents in GL-1 ferments with strain M3 showed about 6-time higher than that of control (not fermented). Consequently, the strain M3 was finally selected for the mass production of Compd K with well-absorbable property in GI tract and physiological activity.     

Physiological activities of ginsenoside-rich fraction isolated from Panax ginseng leaves

In order to develop the new physiologically active materials from the leaves of Panax ginseng C.A. Meyer, the ginsenoside-rich fraction (GL-1) was isolated from ginseng leaves and physiological activities were examined. GL-1 contained crude saponin (ginsenosides, 58.00%) and component ginsenoside analysis using high performance liquid chromatography (HPLC) showed that the major ginsenosides of GL-1 were Re, Rg1, Rc, and F2 and their contents were 34.42, 20.73, 18.42, and 8.60%, respectively. ABTS and DPPH radical scavenging activities of GL-1 were 75.14 and 39.28% at 10,000 μg/mL, respectively. Superoxide anion radical scavenging activity was 70.94% at 1,000 μg/mL. GL-1 also expressed the considerable anti-complementary activity in dose-dependent manner. Results obtained by crossed immunoelectrophoresis using anti-human C3 and anti-complementary activity in the absence of Ca⁺⁺ ion suggested that complement activation by GL-1 from ginseng leaves occur via both alternative and classical pathways.     

超高效液相色谱-四极杆静电场轨道阱高分辨质谱法测定米炒人参炮制前后皂苷成分及其裂解规律的研究

目的 建立超高效液相色谱-四极杆静电场轨道阱高分辨质谱法（ultra performance liquid chromatography-quadrupole-orbitrap-mass spectrometry, UPLC-Q-Orbitrap-MS）检测分析方法。方法 采用Supelco C18色谱柱,以乙腈-0.1%甲酸水溶液梯度洗脱,应用电喷雾离子源（ESI electro-spray ionization）,负离子全扫描模式采集一、二级质谱数据,扫描范围为150~2000 m/z。结合质谱数据库及相关文献信息,运用X Calibur2.2软件对米炒人参中皂苷类成分进行鉴定。以6种人参皂苷Re、Rg1、Rb1、Rc、Rb2、Rb3进行模拟炮制,确定皂苷类成分裂解产物,明确皂苷成分的裂解规律。结果 从人参中检测出14个成分,鉴定出13种人参皂苷成分;米炒人参中检测出23个成分,鉴定出20种人参皂苷成分。通过比较人参米炒前后的皂苷类成分,发现米炒人参中存在人参中未检测到的8种稀有人参皂苷20(S)-Rg2、20(S)-Rh1、20(R)-Rh1、F2、20(S)-Rg3、20(R)-Rg3、20(S)-Rs3、20(R)-Rs3。模拟炮制结果表明,人参皂苷Re脱去C-20糖基,转化为稀有人参皂苷20(S)-Rg2;人参皂苷Rg1脱去C-20位糖基,转化为稀有人参皂苷20(S)-Rh1、20(R)-Rh1;人参皂苷Rb1、Rb2、Rb3、Rc脱去C-20或C-3位糖基,转化为稀有人参皂苷20(S)-Rg3、20(R)-Rg3或F2。结论 人参经米炒后,稀有人参皂苷成分增加,产生的稀有皂苷为原型皂苷发生苷键裂解而获得,模拟炮制可作为其裂解规律研究的有效方法。     

Enhancement of low molecular weight ginsenosides from low-quality ginseng through ultra-high-pressure and fermentation processes

This study aimed to analyze the conversion pattern of high to low molecular weight ginsenosides in low-quality ginseng during lactic acid fermentation associated with an ultra-high-pressure process. It was found that the relative quantities of various low molecular weight ginsenosides were increased by 20 min of pressure treatment at 500 MPa following fermentation with Bifidobacterium longum. Specifically, after ultra-high-pressure extraction, the triol-type, low molecular weight Rg2 was the most abundant ginsenoside, at 1.213 mg/g. However, when low-quality ginseng was fermented, the concentrations of diol-type, low molecular weight ginsenosides (e.g., Compound-K (CK), Rh2, and Rg3) largely increased to 1.52, 1.241, and 0.947 mg/g, respectively. These data indicate that high molecular weight ginsenosides in ginseng could be broken down by two different hydrolysis mechanisms. In the fermentation process, the β-1,2 and β-1,4 glycosidic bonds in high molecular weight ginsenosides such as Re, Rc, and Rb1 were hydrolyzed to diol-type, low molecular weight ginsenosides by the β-glucosidase enzyme of the lactic acid bacterium. Meanwhile, the physical energy of the ultra-high-pressure process specifically hydrolyzed relatively weak bonds of the sugars in high molecular weight ginsenosides such as Re to form the low molecular weight ginsenoside Rg2. Rg2, Rg3, Rh2, and CK increased to 2.043, 1.742, 1.834, and 2.415 mg/g, respectively, possibly due to a synergistic effect of combining both processes. Therefore, low molecular weight ginsenosides with higher biological activities than high molecular weight ginsenosides can be selectively obtained from low-quality ginseng using both fermentation and ultra-high-pressure processes.     

Change of ginsenoside composition in red ginseng processed with citric acid

The purpose of this research was to investigate the composition of ginsenosides and to identify the chemical structures of ginsenosides generated from red ginseng by citric acid pre-treatment (RGC). The amount and the composition of ginsenosides in red ginseng (RG) and RGC were determined by high performance liquid chromatography (HPLC) analysis. The content of Rg₃, a well-known bioactive ginsenoside in RGC increased significantly (p<0.05) over 2 fold (0.411 mg/g) when compared with RG (0.186 mg/g). Moreover, the structures of 5 novel ginsenosides in RGC were investigated by liquid chromatography/mass spectrometry (LC/MS/MS) analysis. Three peaks were completely fragmentized from their mother ions to aglycones and suggested to be less polar ginsenosides Rk₃/Rh₄, Rk₁, and Rg₅. This study suggested that by processing red ginseng with citric acid it is possible to enhance the yield of both ginsenoside Rg₃ and less polar ginsenosides.     

人参酶解物中的皂苷成分及其对髓源抑制性细胞的作用研究

本文建立了同时测定人参酶解物中12种人参皂苷的高效液相色谱检测方法,探索人参提取物及酶解物主要皂苷成分差异,并以酶解前后的人参提取物作为对象,探讨其对髓源抑制性细胞(Myeloid derived suppressed cell,MDSC)的影响。人参提取物和酶解物的总皂苷含量差异不明显,而酶解物中12种人参皂苷和稀有皂苷含量(Rh1、F1、F2、Rg3、CK和Rh2)均显著高于人参提取物;稀有皂苷含量增加了4.48倍,尤其是酶解后转化生成了大量的F2和少量的F1、CK和Rh2等稀有皂苷。人参提取物及酶解物均能显著抑制MSC2细胞增殖和降低结肠癌荷瘤小鼠脾脏中的MDSC细胞比例。其中人参酶解物效果更佳,相对人参提取物,对MSC2细胞增殖抑制率提高30.00%和MDSC细胞比例降低40.50%。人参酶解物含有丰富的稀有皂苷,具有更高的生物活性,能够有效改善肿瘤微环境,从而加强了抗肿瘤能力。     

Inhibitory effect of ginsenosides from ginseng leaves and flowers on the LPS-stimulated IL-12 production in bone marrow-derived dendritic cells

Ginseng leaves and flowers have been known to be rich in various ginsenosides. The aim of present study is to screen the effect of 34 ginsenosides from ginseng leaves and flowers on interlukin (IL)-12 production in bone marrow-derived dendritic cells induced by lipopolysaccharide (LPS). Noticeably, floralginsenoside Kc (5), floralginsenoside J (26), and ginsenoside I (33) exhibited particularly inhibitory effect on LPS-induced IL-12 production with IC₅₀ values of 16.3, 25.8, and 6.7 μM, respectively. In addition, floralginsenoside Kc (5) suppressed significantly LPS-stimulated IL-6 and tumor necrosis factor-α (TNF-α) production. These results warrant further studies concerning potential of saponin extracts of Panax ginseng leaves and flowers for medicinal foods.     

人参皂苷活性对冠心病作用的研究进展

人参是在我国应用历史悠久的医食两用养生珍品,具有提高机体免疫力、缓解疲劳、抗衰老等作用。本文主要综述了人参主要的活性成分,人参皂苷的分类及毒性,人参活性成分与炎症反应、氧化应激、细胞凋亡、细胞自噬、线粒体损伤、钙超载的关系,以及人参皂苷在抗动脉粥样硬化、抗心律失常、抗心肌缺血、抑制心室重构方面的作用,以期为利用人参活性成分研发提供理论依据。     

Cytotoxicity of the white ginseng extract and red ginseng extract treated with partially purified β-glucosidase from Aspergillus usamii KCTC 6954

Red ginseng extract (RGE) and white ginseng extract (WGE) were treated with partially purified β-glucosidase to increase a production of minor ginsenosides. The enzyme produced from Aspergillus usamii KCTC 6954 was precipitated with (NH₄)₂SO₄. Ginseng extracts were treated with a crude extract possessing β-glucosidase activity (1,089.2 μM/mL·min) at 60°C for 72 h. The results of HPLC showed that enzyme-treated RGE and enzymetreated WGE have increased amounts of minor ginsenosides compared to each controls implying that the ginsenoside Rb₁ in WGE and RGE is converted enzymatically to Rd, F₂, Rg₃, and compound K. In cytotoxicity study, 2.5 mg/mL of RGE, 1.25 mg/mL of ERGE, and 5 mg/mL of WGE and EWGE were effective against the HepG2, AGS, and DLD-1, but HeLa and SK-MES-1 were not affected at any concentration. The results suggested that cytotoxicity of ginseng extracts treated with β-glucosidase were greater than that of each control against cancer cells.     

超临界CO2 反相微乳萃取人参皂甙的研究

利用萃取罐体积为1 L 的超临界CO2 萃取设备,采用琥珀酸二(2- 乙基己基)酯磺酸钠(AOT)/ 乙醇/ 水/ 超临界CO2 反相微乳对人参皂甙的萃取进行了研究。结果表明：最优萃取参数为萃取温度55℃,萃取时间3h,加水量 36ml/100g 人参,萃取压力 30MPa 和 AOT 添加量0.06mol/100g 人参,此时人参皂甙的得率为0.757%;E=0.870 ×(1 － e-0.618t)为超临界CO2 反相微乳萃取人参皂甙的具体动力学模型方程;超临界CO2 反相微乳萃取与超临界CO2 萃取人参皂甙相比是一种相对有效的萃取技术。     

人参皂苷生物转化及固体发酵工艺研究进展

研究表明,人参皂苷在体外可以转化成多种稀有皂苷,它们是在生物体内发挥药理活性的关键物质。微生物转化法及固体发酵技术是工业化生产稀有人参皂苷的基础。文中针对皂苷生物转化研究概况进行综述,探讨了固体发酵工艺条件,并对目前人参皂苷生物转化研究中存在的问题及今后的主要发展方向进行了展望。