Correction: Icariin and icaritin recover UVB-induced photoaging by stimulating Nrf2/ARE and reducing AP-1 and NF-κB signaling pathways: a comparative study on UVB-irradiated human keratinocytes.

Correction for 'Icariin and icaritin recover UVB-induced photoaging by stimulating Nrf2/ARE and reducing AP-1 and NF-κB signaling pathways: a comparative study on UVB-irradiated human keratinocytes' by Eunson Hwang et al., Photochem. Photobiol. Sci., 2018, 17, 1396-1408.

Icariin and icaritin recover UVB-induced photoaging by stimulating Nrf2/ARE and reducing AP-1 and NF-κB signaling pathways: a comparative study on UVB-irradiated human keratinocytes.

Icariin (ICA) and icaritin (ICT) exhibit many pharmacological functions including anti-osteoporosis, anti-cardiovascular, and anti-cancer activities; however, there are few comprehensive studies that track the detailed effects on UVB-induced photoaging. The recovery effects of ICA and ICT were investigated in UVB-irradiated human keratinocytes (HaCaTs). The results indicated that ICT and ICA showed strong radical scavenging activity, and the reactive oxygen species (ROS) scavenging activity of ICT was superior. UVB-induced matrix metalloproteinase-1 (MMP-1) expression was blocked by ICA via the inhibition of mitogen-activated protein kinase/activator protein 1 (MAPK/AP-1), which directly reduced extracellular matrix (ECM) degradation. ICT activated nuclear factor erythroid 2 related factor 2 (Nrf2) to improve the anti-oxidative stress capacity and suppress nuclear factor-κB (NF-κB) activation, decreasing vascular endothelial growth factor (VEGF) protein, and inflammatory cytokines induced ECM degrading enzyme secretion. Moreover, ICT was more advantageous to improve transforming growth factor beta 1 (TGF-ß1) and procollagen type I expression than ICA, promoting the synthesis of collagen. Therefore, ICA and ICT have potential to treat UVB-induced oxidative stress, inflammation and photoaging, and will be posited as a novel strategy to alleviate photodamage.

Terrabacter ginsengisoli sp. nov., isolated from ginseng cultivating soil.

A Gram-positive, strictly aerobic, nonmotile, yellowish, coccus-rod-shaped bacterium (designated Gsoil 653T) isolated from ginseng cultivating soil was characterized using a polyphasic approach to clarify its taxonomic position. The strain Gsoil 653T exhibited optimal growth at pH 7.0 on R2A agar medium at 30°C. Phylogenetic analysis based on 16S rRNA gene sequence similarities, indicated that Gsoil 653T belongs to the genus Terrabacter of the family Humibacillus, and was closely related to Terrabacter tumescens DSM 20308T (98.9%), Terrabacter carboxydivorans PY2T (98.9%), Terrabacter terrigena ON10T (98.8%), Terrabacter terrae PPLBT (98.6%), and Terrabacter lapilli LR-26T (98.6%). The DNA G + C content was 70.5 mol%. The major quinone was MK-8(H4). The primary polar lipids were phosphatidylglycerol, diphosphatidylglycerol, phosphatidyl-ethanolamine. The predominant fatty acids were iso-C15:0, iso-C16:0, iso-C14:0, and anteiso-C15:0, as in the case of genus Terrabacter, thereby supporting the categorization of strain Gsoil 653T. However, the DNA-DNA relatedness between Gsoil 653T and closely related strains of Terrabacter species was low at less than 31%. Moreover, strain Gsoil 653T could be both genotypically and phenotypically distinguished from the recognized species of the genus Terrabacter. This isolate, therefore, represents a novel species, for which the name Terrabacter ginsengisoli sp. nov. is proposed with the type strain Gsoil 653T (= KACC 19444T = LMG 30325T).

Baekduia soli gen. nov., sp. nov., a novel bacterium isolated from the soil of Baekdu Mountain and proposal of a novel family name, Baekduiaceae fam. nov.

A taxonomic study was conducted on BR7-21T, a bacterial strain isolated from the soil of a ginseng field in Baekdu Mountain. Comparative studies of the 16S rRNA gene sequence showed that the isolate was most closely related to Conexibacter woesei DSM 14684T, Solirubrobacter pauli ATCC BAA-492T, Patulibacter minatonensis JCM 12834T, with 93.8%, 92.4%, and 91.5% sequence similarity, respectively; each genus represented a family in the order Solirubrobacterales. Strain BR7-21T was Gram-reaction positive, non-spore forming, aerobic, non-motile, and short rod-shaped. It grew well on half-strength R2A medium. The G + C content of the genomic DNA was 73.9%. It contained meso-diaminopimelic acid in the cell wall and the major menaquinones were MK-7(H4) and MK-8(H4). The major fatty acids were summarized as (C16:1ω7c/iso-C15:0 2-OH), iso-C16:0, and C17:0 cyclo. On the basis of polyphasic evidence, it was proposed that strain BR7-21T should be placed in a new genus and species, for which the name Baekduia soli gen. nov., sp. nov. was proposed with the type strain BR7-21T (= KCTC 22257T = LMG 24797T). The family Baekduiaceae fam. nov. is proposed to encompass the genus Baekduia gen. nov.

Mucilaginibacter panaciglaebae sp. nov., isolated from soil of a ginseng field.

A Gram-reaction-negative, strictly aerobic, non-motile and rod-shaped bacterium, designated strain BXN5-31T, was isolated from soil of a ginseng field, and its taxonomic position was investigated using a polyphasic approach. Strain BXN5-31T grew at 18-37 °C and at pH 6.0-8.0 on R2A medium. Based on 16S rRNA gene sequence similarity, strain BXN5-31T was shown to belong to the genus Mucilaginibacter and was closely related to Mucilaginibactersoyangensis HME6664T, Mucilaginibacterximonensis XM-003T and Mucilaginibacterpuniceus WS71T. The DNA G+C content was 43.6 %. The predominant respiratory quinone was menaquinone 7 (MK-7) and the major fatty acids were iso-C15 : 0, iso-C17 : 0 3-OH and summed feature 3 (comprising C16 : 1ω6c and/or C16 : 1ω7c). The major polar lipids were phosphatidylglycerol, diphosphatidylglycerol and phosphatidylethanolamine. The DNA-DNA hybridization values between strain BXN5-31T and three reference strains (M. soyangensis HME6664T, M. ximonensis XM-003T and M. puniceus WS71T) were 9.4±1.9, 8.2±1.3 and 5.7±0.7 %, respectively. The DNA G+C content and chemotaxonomic data supported the affiliation of strain BXN5-31T to the genus Mucilaginibacter. Moreover, the physiological and biochemical results and low level of DNA-DNA relatedness allowed the phenotypic and genotypic differentiation of strain BXN5-31T from recognized species of the genus Mucilaginibacter. The isolate therefore represents a novel species, for which the name Mucilaginibacter panaciglaebae sp. nov. is proposed. The type strain is BXN5-31T (=KACC 14957T=JCM 17085T).

Gram-Scale Production of Ginsenoside F1 Using a Recombinant Bacterial ß-Glucosidase.

Naturally occurring ginsenoside F1 (20-O-ß-D-glucopyranosyl-20(S)-protopanaxatriol) is rare. Here, we produced gram-scale quantities of ginsenoside F1 from a crude protopanaxatriol saponin mixture comprised mainly of Re and Rg1 through enzyme-mediated biotransformation using recombinant ß-glucosidase (BgpA) cloned from a soil bacterium, Terrabacter ginsenosidimutans Gsoil 3082T. In a systematic step-by-step process, the concentrations of substrate, enzyme, and NaCl were determined for maximal production of F1. At an optimized NaCl concentration of 200 mM, the protopanaxatriol saponin mixture (25 mg/ml) was incubated with recombinant BgpA (20 mg/ml) for 3 days in a 2.4 L reaction. Following octadecylsilyl silica gel column chromatography, 9.6 g of F1 was obtained from 60 g of substrate mixture at 95% purity, as assessed by chromatography. These results represent the first report of gramscale F1 production via recombinant enzyme-mediated biotransformation.

Preparation of minor ginsenosides C-Mc, C-Y, F2, and C-K from American ginseng PPD-ginsenoside using special ginsenosidase type-I from Aspergillus niger g.848.

BACKGROUND: Minor ginsenosides, those having low content in ginseng, have higher pharmacological activities. To obtain minor ginsenosides, the biotransformation of American ginseng protopanaxadiol (PPD)-ginsenoside was studied using special ginsenosidase type-I from Aspergillus niger g.848. METHODS: DEAE (diethylaminoethyl)-cellulose and polyacrylamide gel electrophoresis were used in enzyme purification, thin-layer chromatography and high performance liquid chromatography (HPLC) were used in enzyme hydrolysis and kinetics; crude enzyme was used in minor ginsenoside preparation from PPD-ginsenoside; the products were separated with silica-gel-column, and recognized by HPLC and NMR (Nuclear Magnetic Resonance). RESULTS: The enzyme molecular weight was 75 kDa; the enzyme firstly hydrolyzed the C-20 position 20-O-ß-D-Glc of ginsenoside Rb1, then the C-3 position 3-O-ß-D-Glc with the pathway Rb1→Rd→F2→C-K. However, the enzyme firstly hydrolyzed C-3 position 3-O-ß-D-Glc of ginsenoside Rb2 and Rc, finally hydrolyzed 20-O-L-Ara with the pathway Rb2→C-O→C-Y→C-K, and Rc→C-Mc1→C-Mc→C-K. According to enzyme kinetics, K m and V max of Michaelis-Menten equation, the enzyme reaction velocities on ginsenosides were Rb1 > Rb2 > Rc > Rd. However, the pure enzyme yield was only 3.1%, so crude enzyme was used for minor ginsenoside preparation. When the crude enzyme was reacted in 3% American ginseng PPD-ginsenoside (containing Rb1, Rb2, Rc, and Rd) at 45°C and pH 5.0 for 18 h, the main products were minor ginsenosides C-Mc, C-Y, F2, and C-K; average molar yields were 43.7% for C-Mc from Rc, 42.4% for C-Y from Rb2, and 69.5% for F2 and C-K from Rb1 and Rd. CONCLUSION: Four monomer minor ginsenosides were successfully produced (at low-cost) from the PPD-ginsenosides using crude enzyme.

Identification and characterization of a ginsenoside-transforming ß-glucosidase from Pseudonocardia sp. Gsoil 1536 and its application for enhanced production of minor ginsenoside Rg2(S).

The ginsenoside Rg2(S), which is one of the pharmaceutical components of ginseng, is known to have neuroprotective, anti-inflammation, and anti-diabetic effects. However, the usage of ginsenoside Rg2(S) is restricted owing to the small amounts found in white and red ginseng. To enhance the production of ginsenoside Rg2(S) as a 100 gram unit with high specificity, yield, and purity, an enzymatic bioconversion method was developed to adopt the recombinant glycoside hydrolase (BglPC28), which is a ginsenoside-transforming recombinant ß-glucosidase from Pseudonocardia sp. strain Gsoil 1536. The gene, termed bglPC28, encoding ß-glucosidase (BglPC28) belonging to the glycoside hydrolase family 3 was cloned. bglPC28 consists of 2,232 bp (743 amino acid residues) with a predicted molecular mass of 78,975 Da. This enzyme was overexpressed in Escherichia coli BL21(DE3) using a GST-fused pGEX 4T-1 vector system. The optimum conditions of the recombinant BglPC28 were pH 7.0 and 37 °C. BglPC28 can effectively transform the ginsenoside Re to Rg2(S); the Km values of PNPG and Re were 6.36 ± 1.10 and 1.42 ± 0.13 mM, respectively, and the Vmax values were 40.0 ± 2.55 and 5.62 ± 0.21 µmol min-1 mg-1 of protein, respectively. A scaled-up biotransformation reaction was performed in a 10 L jar fermenter at pH 7.0 and 30°C for 12 hours with a concentration of 20 mg/ml of ginsenoside Re from American ginseng roots. Finally, 113 g of Rg2(S) was produced from 150 g of Re with 84.0 ± 1.1% chromatographic purity. These results suggest that this enzymatic method could be usefully exploited in the preparation of ginsenoside Rg2(S) in the cosmetics, functional food, and pharmaceutical industries.

Kinetics of a cloned special ginsenosidase hydrolyzing 3-O-glucoside of multi-protopanaxadiol-type ginsenosides, named ginsenosidase type III.

In this paper, the kinetics of a cloned special glucosidase, named ginsenosidase type III hydrolyzing 3-O-glucoside of multi-protopanaxadiol (PPD)-type ginsenosides, were investigated. The gene (bgpA) encoding this enzyme was cloned from a Terrabacter ginsenosidimutans strain and then expressed in E. coli cells. Ginsenosidase type III was able to hydrolyze 3-O-glucoside of multi-PPD-type ginsenosides. For instance, it was able to hydrolyze the 3-O-ß-D-(1-->2)-glucopyranosyl of Rb1 to gypenoside XVII, and then to further hydrolyze the 3-O-ß-D-glucopyranosyl of gypenoside XVII to gypenoside LXXV. Similarly, the enzyme could hydrolyze the glucopyranosyls linked to the 3-O- position of Rb2, Rc, Rd, Rb3, and Rg3. With a larger enzyme reaction Km value, there was a slower enzyme reaction speed; and the larger the enzyme reaction Vmax value, the faster the enzyme reaction speed was. The Km values from small to large were 3.85 mM for Rc, 4.08 mM for Rb1, 8.85 mM for Rb3, 9.09 mM for Rb2, 9.70 mM for Rg3(S), 11.4 mM for Rd and 12.9 mM for F2; and Vmax value from large to small was 23.2 mM/h for Rc, 16.6 mM/h for Rb1, 14.6 mM/h for Rb3, 14.3 mM/h for Rb2, 1.81mM/h for Rg3(S), 1.40 mM/h for Rd, and 0.41 mM/h for F2. According to the Vmax and Km values of the ginsenosidase type III, the hydrolysis speed of these substrates by the enzyme was Rc>Rb1>Rb3>Rb2>Rg3(S)>Rd>F2 in order.

A novel ginsenosidase from an Aspergillus strain hydrolyzing 6-O-multi-glycosides of protopanaxatriol-type ginsenosides, named ginsenosidase type IV.

Herein, a novel ginsenosidase, named ginsenosidase type IV, hydrolyzing 6-O-multi-glycosides of protopanaxatrioltype ginsenosides (PPT), such as Re, R1, Rf, and Rg2, was isolated from the Aspergillus sp. 39g strain, purified, and characterized. Ginsenosidase type IV was able to hydrolyze the 6-O-alpha-L-(1-->2)-rhamnoside of Re and the 6-O-beta-D- (1-->2)-xyloside of R1 into ginsenoside Rg1. Subsequently, it could hydrolyze the 6-O-beta-D-glucoside of Rg1 into F1. Similarly, it was able to hydrolyze the 6-O-alpha-L-(1-->2)- rhamnoside of Rg2 and the 6-O-beta-D-(1-->2)-glucoside of Rf into Rh1, and then further hydrolyze Rh1 into its aglycone. However, ginsenosidase type IV could not hydrolyze the 3-O- or 20-O-glycosides of protopanaxadioltype ginsenosides (PPD), such as Rb1, Rb2, Rb3, Rc, and Rd. These exhibited properties are significantly different from those of glycosidases described in Enzyme Nomenclature by the NC-IUBMB. The optimal temperature and pH for ginsenosidase type IV were 40°C and 6.0, respectively. The activity of ginsenosidase type IV was slightly improved by the Mg(2+) ion, and inhibited by Cu(2+) and Fe(2+) ions. The molecular mass of the enzyme, based on SDS-PAGE, was noted as being approximately 56 kDa.

Hymenobacter daecheongensis sp. nov., isolated from stream sediment.

A Gram-negative, strictly aerobic, non-spore-forming, rod-shaped, red-pink bacterium, designated strain Dae14(T), was isolated from stream sediment collected near Daecheong Dam, South Korea, and its taxonomic position was investigated by using a polyphasic approach. Phylogenetic analysis of 16S rRNA gene sequences showed that strain Dae14(T) belonged to the genus Hymenobacter. Sequence similarities between strain Dae14(T) and the type strains of Hymenobacter species with validly published names ranged from 91.3 to 94.3 %. The predominant cellular fatty acids of strain Dae14(T) were iso-C(15 : 0), C(16 : 1)omega5c, summed feature 5 (iso-C(17 : 1) I and/or anteiso-C(17 : 1) B) and iso-C(16 : 0). The DNA G+C content was 62.2 mol%. Results of phylogenetic, chemotaxonomic and phenotypic characterization indicated that strain Dae14(T) can be distinguished from all known Hymenobacter species and represents a novel species, for which the name Hymenobacter daecheongensis sp. nov. is proposed, with Dae14(T) (=KCTC 22258(T)=LMG 24498(T)) as the type strain.

Emticicia ginsengisoli sp. nov., a species of the family 'Flexibacteraceae' isolated from soil of a ginseng field.

A taxonomic study was carried out on Gsoil 085T, a bacterial strain isolated from a soil sample from a ginseng field in Pocheon Province (South Korea). Comparative 16S rRNA gene sequence studies showed a clear affiliation of this bacterium to the family 'Flexibacteraceae' and indicated that the closest relative was Emticicia oligotrophica GPTSA100-15T (94.6 % sequence similarity). Lower sequence similarities (<83.0 %) were found with respect to all other recognized species of the family 'Flexibacteraceae'. Strain Gsoil 085T was found to be Gram-negative, strictly aerobic, non-motile and rod-shaped. It grew well on half-strength R2A medium but did not utilize a broad range of carbon sources. The G+C content of the genomic DNA was 40.5 mol%. The major fatty acids were summed feature 4 (iso-C15 : 0 2-OH and/or C16 : 1omega7c, 45.4 %), iso-C15 : 0 (13.9 %), C16 : 1omega5c (8.6 %) and C16 : 0 (8.2 %). On the basis of evidence from the polyphasic study, strain Gsoil 085T represents a novel species of the genus Emticicia, for which the name Emticicia ginsengisoli sp. nov. is proposed. The type strain is Gsoil 085T (=KCTC 12588T =LMG 23396T).

Kaistia granuli sp. nov., isolated from anaerobic granules in an upflow anaerobic sludge blanket reactor.

A Gram-negative, chemo-organotrophic, non-motile, non-spore-forming, rod-shaped bacterium (designated strain Ko04(T)) was isolated from anaerobic granules in an upflow anaerobic sludge blanket reactor, and was investigated using a polyphasic taxonomic approach. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain Ko04(T) belongs to the order Rhizobiales in the Alphaproteobacteria. Comparative 16S rRNA gene sequence analysis showed that strain Ko04(T) was most closely related to Kaistia adipata (97.5 %) and that sequence similarities with other species of Rhizobiales with validly published names were less than 92.5 %. The predominant ubiquinone was Q-10 and the major fatty acids were C(18 : 1)omega7c/omega9t/omega12t, C(19 : 0 )cyclo omega8c and C(18 : 0). The G+C content of the genomic DNA of strain Ko04(T) was 67.8 mol%. The level of DNA-DNA relatedness with K. adipata Chj404(T) was 15 %. The results of the genotypic analyses in combination with chemotaxonomic and physiological data demonstrated that strain Ko04(T) represents a novel species within the genus Kaistia, for which the name Kaistia granuli sp. nov. is proposed. The type strain is Ko04(T) (=KCTC 12575(T)=LMG 23410(T)).