Protective Effect of Castanopsis sieboldii Extract against UVB-Induced Photodamage in Keratinocytes.

Ultraviolet B (UVB) rays disrupt the skin by causing photodamage via processes such as reactive oxygen species (ROS) production, endoplasmic reticulum (ER) stress, DNA damage, and/or collagen degradation. Castanopsis sieboldii is an evergreen tree native to the southern Korean peninsula. Although it is known to have antioxidant and anti-inflammatory effects, its protective effect against photodamage in keratinocytes has not been investigated. Thus, in the present study, we investigated the effect of 70% ethanol extract of C. sieboldii leaf (CSL3) on UVB-mediated skin injuries and elucidated the underlying molecular mechanisms. CSL3 treatment restored the cell viability decreased by UVB irradiation. Moreover, CSL3 significantly inhibited UVB- or tert-butyl hydroperoxide-mediated ROS generation in HaCaT cells. ER stress was inhibited, whereas autophagy was upregulated by CSL3 treatment against UVB irradiation. Additionally, CSL3 increased collagen accumulation and cell migration, which were decreased by UVB exposure. Notably, epigallocatechin gallate, the major component of CSL3, improved the cell viability decreased by UVB irradiation through regulation of ER stress and autophagy. Conclusively, CSL3 may represent a promising therapeutic candidate for the treatment of UVB-induced skin damage.

Bamboo Lignin Fractions with In Vitro Tyrosinase Inhibition Activity Downregulate Melanogenesis in B16F10 Cells via PKA/CREB Signaling Pathway.

Cosmetic ingredients originating from natural resources have garnered considerable attention, and the demand for whitening ingredients is increasing, particularly in Asian countries. Lignin is a natural phenolic biopolymer significantly effective as a natural sunscreen, as its ultraviolet protection efficacy ranges from 250 to 400 nm. However, using different types of lignin as cosmetic ingredients is difficult owing to the heterogeneity of lignin and the lack of in vitro and in vivo safety and efficacy data. Thus, steam-exploded lignin (SEL) was prepared from bamboo, fractionated via successive organic solvent extraction, and sequentially fractionated using ethyl acetate, methanol, and acetone to investigate its potential as a natural whitening material. Gel permeation chromatography showed that the molecular weight of acetone-soluble and acetone-insoluble SEL fractions were the lowest and the highest, respectively. Monomer structures of the four lignin fractions were elucidated using 1H, 13C, and 2D heteronuclear single quantum coherence nuclear magnetic resonance and pyrolysis gas chromatography/mass spectrometry. The antioxidant and tyrosinase inhibition activities of the four fractions were compared. The methanol-soluble SEL fraction (SEL-F2) showed the highest antioxidant activity (except 2,2-diphenyl-1-picrylhydrazyl scavenging activity), and the enzyme inhibition kinetics were confirmed. In this study, the expression pattern of the anti-melanogenic-related proteins by SEL-F2 was confirmed for the first time via the protein kinase A (PKA)/cAMP-response element-binding (CREB) protein signaling pathway in B16F10 melanoma cells. Thus, SEL may serve as a valuable cosmetic whitening ingredient.

Novel Quercetin Derivative of 3,7-Dioleylquercetin Shows Less Toxicity and Highly Potent Tyrosinase Inhibition Activity.

Quercetin is a well-known plant flavonol and antioxidant; however, there has been some debate regarding the efficacy and safety of native quercetin as a skin-whitening agent via tyrosinase inhibition. Several researchers have synthesized quercetin derivatives as low-toxicity antioxidants and whitening agents. However, no suitable quercetin derivatives have been reported to date. In this study, a novel quercetin derivative was synthesized by the SN2 reaction using quercetin and oleyl bromide. The relationship between the structures and activities of quercetin derivatives as anti-melanogenic agents was assessed using in vitro enzyme kinetics, molecular docking, and quenching studies; cell line experiments; and in vivo zebrafish model studies. Novel 3,7-dioleylquercetin (OQ) exhibited a low cytotoxic concentration level at >100 µg/mL (125 µM), which is five times less toxic than native quercetin. The inhibition mechanism showed that OQ is a competitive inhibitor, similar to native quercetin. Expression of tyrosinase, tyrosinase-related protein 1 (TRP-1) and tyrosinase-related protein 2 (TRP-2), and microphthalmia-associated transcription factor was inhibited in B16F10 melanoma cell lines. mRNA transcription levels of tyrosinase, TRP-1, and TRP-2 decreased in a dose-dependent manner. Melanin formation was confirmed in the zebrafish model using quercetin derivatives. Therefore, OQ might be a valuable asset for the development of novel skin-whitening agents.

Self-assembled Viral Nanoparticles as Targeted Anticancer Vehicles.

Viral nanoparticles (VNPs) comprise a variety of mammalian viruses, plant viruses, and bacteriophages, that have been adopted as building blocks and supra-molecular templates in nanotechnology. VNPs demonstrate the dynamic, monodisperse, polyvalent, and symmetrical architectures which represent examples of such biological templates. These programmable scaffolds have been exploited for genetic and chemical manipulation for displaying of targeted moieties together with encapsulation of various payloads for diagnosis or therapeutic intervention. The drug delivery system based on VNPs offer diverse advantages over synthetic nanoparticles, including biocompatibility, biodegradability, water solubility, and high uptake capability. Here we summarize the recent progress of VNPs especially as targeted anticancer vehicles from the encapsulation and surface modification mechanisms, involved viruses and VNPs, to their application potentials.

Antioxidative and Anti-Melanogenic Activities of Bamboo Stems (Phyllostachys nigra variety henosis) via PKA/CREB-Mediated MITF Downregulation in B16F10 Melanoma Cells.

Phyllostachys nigra var. henosis, a domestic bamboo species, has been attracting much attention; its bioactive compounds (especially in the leaf) show antioxidant, anti-inflammatory, and anti-obesity activities. Little information is available on the antioxidative and anti-melanogenetic activities of the bioactive compounds in bamboo stems. The anti-melanogenic and antioxidative activities of the EtOAc fraction (PN3) of a P. nigra stem extract were investigated in a cell-free system and in B16F10 melanoma cells. PN3 consisted of a mixture of flavonoids, such as catechin, chlorogenic acid, caffeic acid, and p-coumaric acid. The antioxidant activity (2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid (ABTS)), and hydroxyl radical scavenging) was evaluated, as well as the inhibition of reactive oxygen species (ROS) produced by the Fenton reaction. PN3 showed in vitro tyrosinase inhibition activity with the half maximal inbihitory concentration (IC50) values of 240 µg/mL, and in vivo cytotoxic concentration ranges > 100 µg/mL. The protein expression levels and mRNA transcription levels of TYR, TRP-1, and MITF were decreased in a dose-dependent manner by the treatment with PN3. PN3 interfered with the phosphorylation of intracellular protein kinase A (PKA)/cAMP response element-binding protein (CREB), demonstrating potent anti-melanogenic effects. PN3 could inhibit PKA/CREB and the subsequent degradation of microphthalmia-associated transcription factor (MITF), resulting in the suppression of melanogenic enzymes and melanin production, probably because of the presence of flavonoid compounds. These properties make it a candidate as an additive to whitening cosmetics.

Encapsulation and crystallization of Prussian blue nanoparticles by cowpea chlorotic mottle virus capsids.

Cowpea chlorotic mottle virus (CCMV) capsids were used to encapsulate Prussian blue (PB) particles based on electrostatic interaction. A negatively-charged metal complex, hexacyanoferrate (III), was entrapped inside the capsids through the disassembly/reassembly process under a pH change from 7.5 to 5.2. The loaded capsids reacted with a second Fe(II) to fabricate PB particles. The synthesis of PB in CCMV capsids was confirmed by a unique colour transition at 710 nm and by size-exclusion FPLC. Transmission electron microscopy images of PB-CCMV biohybrids presented discrete spherical particles with a relatively homogeneous size. Dynamic light scattering of PB-CCMV showed two peaks of 29.2 ± 1.7 nm corresponding to triangulation number T = 3 particles, and 17.5 ± 1.2 nm of pseudo T = 2 particles. The encapsulation and crystallization of PB in CCMV provided an efficient method for the self-organization of bimetallic nanoparticles.

Improved cell disruption of Pichia pastoris utilizing aminopropyl magnesium phyllosilicate (AMP) clay.

An efficient method for Pichia cell disruption that employs an aminopropyl magnesium phyllosilicate (AMP) clay-assisted glass beads mill is presented. AMP clay is functionalized nanocomposite resembling the talc parent structure Si8Mg6O20(OH)4 that has been proven to permeate the bacterial membrane and cause cell lysis. The recombinant capsid protein of cowpea chlorotic mottle virus (CCMV) expressed in Pichia pastoris GS115 was used as demonstration system for their ability of self-assembly into icosahedral virus-like particles (VLPs). The total protein concentration reached 4.24 mg/ml after 4 min treatment by glass beads mill combined with 0.2 % AMP clay, which was 11.2 % higher compared to glass beads mill only and the time was half shortened. The stability of purified CCMV VLPs illustrated AMP clay had no influence on virus assembly process. Considering the tiny amount added and simple approach of AMP clay, it could be a reliable method for yeast cell disruption.

Ethyl Gallate Isolated from Castanopsis cuspidata var. sieboldii Branches Inhibits Melanogenesis and Promotes Autophagy in B16F10 Cells.

The Castanopsis cuspidata var. sieboldii (CCS) plant grows predominantly in temperate regions of Asian countries, such as South Korea. Research on CCS has so far concentrated on the nutritional analysis, antioxidant activity, and anti-inflammation properties of its branches. However, the isolation of compounds and structural elucidation of effective single molecules remain unexplored, necessitating further exploration of CCS branches. Therefore, this study demonstrates the antioxidant and antimelanogenic activity of a single substance of ethyl gallate (EG) isolated from CCS branch extracts. Notably, the antimelanogenic (whitening) activity of EG extracted from CCS branches remains unexplored. Tyrosinase inhibition, kinetic enzyme assays, and molecular docking studies were conducted using mushroom tyrosinase in order to examine the antioxidant mechanism and antimelanin activity of EG in B16F10 melanoma cells. Nontoxic EG concentrations were found to be below 5 µg/mL. While EG significantly reduced the levels of whitening-associated proteins, p-CREB, and p-PKA, it dose-dependently inhibited the expression of TYR, TRP-1, TRP-2, and transcription factor (MITF). In addition, EG downregulated melanogenetic gene expression and activated autophagy signals. Therefore, EG extracted from CCS branches could serve as a novel functional cosmetic material with antimelanogenic and autophagy-enhancing activity.

Versatile applications of the culinary-medicinal mushroom Mycoleptodonoides aitchisonii (Berk.) Maas G. (Higher Basidiomycetes): a review.

Higher Basidiomycetes medicinal mushroom Mycoleptodonoides aitchisonii has become attractive as a natural health product because of its antihypertensive effects on human health. Moreover, the food industry is especially interested in the preparation of the nutritional tonic of this mushroom. Various studies on this mushroom have shown that it has antidiabetic, antihypertensive, and antioxidant effects. The aim of this review is to report the present findings from studies on this mushroom and to discuss its future prospects.

Mycofabrication of Mycelium-Based Leather from Brown-Rot Fungi.

Sustainable substitutes for leather can be made from mushroom mycelium, which is an environmentally friendly alternative to animal and synthetic leather. Mycelium-based leather is derived from Polyporales, in which lignocellulosic material is used as the substrate. The plasticizing and crosslinking of mycelial mats with various reagents might affect the leather properties and mycelial architecture. This study investigated the physicochemical and mechanical properties of mycelium-based leather (MBL) samples, including the hygroscopic nature, thermal stability, cell wall chemistry, density, micromorphology, tensile strength, elongation rate, and Young's modulus. Micromorphological observations confirmed the mycelial networks and their binding performance, verifying their efficacy as a substitute leather. The most significant effects were observed after treatment with 20% polyethylene glycol, which resulted in an increase in Young's modulus and tensile strength. Furthermore, the samples generally exhibited a high density (1.35, 1.46 g/cm3) and tensile strength (7.21 ± 0.93, 8.49 ± 0.90 MPa), resembling leather. The tear strength reached as low as 0.5-0.8 N/mm. However, the tensile and tear strength may be affected by leather processing and the tuning of mycelial growth. Nevertheless, high-density mycelia are shown to be suitable for the production of MBL, while mycofabrication and strain selection are sustainable for novel industrial applications of MBL.

Nomilin from Yuzu Seed Has In Vitro Antioxidant Activity and Downregulates Melanogenesis in B16F10 Melanoma Cells through the PKA/CREB Signaling Pathway.

Yuzu (Citrus junos) is a citrus plant native to Asian countries, including Korea, Japan, and China. Yuzu peel and seed contain abundant vitamin C, citric acid, and polyphenols. Although the antioxidative and antimelanogenic activities of other citrus fruits and yuzu extract have been reported, the tyrosinase inhibitory activity of the limonoid aglycone contained in yuzu seed extract is unknown. We separated yuzu seeds into the husk, shell, and meal and evaluated antioxidant activity of each. The limonoid glucoside fraction of the husk identified nomilin, a novel tyrosinase inhibitor. We performed tyrosinase inhibitory activity and noncompetitive inhibition assays and docking studies to determine nomilin binding sites. Furthermore, we evaluated the antioxidative mechanism and antimelanogenic activity of nomilin in B16F10 melanoma cells. The concentration of nomilin that did not show toxicity was <100 µg/mL. Nomilin suppressed protein expression of TYR, TRP-1, TRP-2, and microphthalmia-associated transcription factor (MITF) in a concentration-dependent manner. Nomilin significantly reduced the levels of p-CREB and p-PKA at the protein level and decreased the levels of skin-whitening-related factors MITF, tyrosinase, TRP-1, and TRP-2 at the mRNA level in a concentration-dependent manner. Thus, nomilin from yuzu seed husk can be used as a skin-whitening agent in cosmetics.

Properties and potential applications of the culinary-medicinal cauliflower mushroom, Sparassis crispa Wulf.:Fr. (Aphyllophoromycetideae): a review.

Sparassis crispa is a culinary-medicinal mushroom that has recently become popular in Korea, China, Japan, Germany, and the USA. S. crispa is a good source of food and nutraceuticals, or dietary supplements, due to its rich flavor compounds and beta-glucan content. This review is a comprehensive summary of its distribution, growth, management, general constituents, functional ingredients, as well as its current and potential medicinal and other applications.

Anterior Approaches for Two-Level Cervical Degenerative Disease: A Comparative Study of at least 6-Year Follow-Up.

OBJECTIVE: To compare the clinical and radiogrincaphic results of a hybrid surgery (HS) and cervical artificial disc replacement (ADR) for contiguous two-level cervical spondylosis. METHODS: A total of 56 patients with contiguous two-level degenerative cervical spondylosis who underwent cervical HS and ADR via an anterior approach and completed at least 6 years of follow-up were included in this study. Patients were divided into two groups: group I, comprising 22 patients who underwent ADR, and group II, comprising 34 patients who underwent HS combined ADR and anterior cervical discectomy and fusion using a cage. Clinical outcomes were evaluated based on the visual analog scale (VAS) scores for arm pain, neck disability index (NDI), and modified MacNab criteria. Radiological parameters were assessed by measuring the bone fusion status, cervical range of motion (ROM C2-C7), heterotopic ossification (HO), adjacent segment disease (ASD) incidence, and fused segment height (FSH). RESULTS: The VAS scores and NDI significantly improved in both groups, without significant differences between the groups. The incidences of HO, ROM C2-C7, and FSH were similar between groups, without significant differences. New osteophyte formation and osteophyte enlargement at adjacent segments were more frequently found in the HS group; however, the difference was not significant. CONCLUSION: Clinical results of this study showed that the clinical efficacy and radiological changes in HS were similar to those of ADR. HS can be an alternative procedure for the treatment of two-level cervical spondylosis.

Delayed Onset Acute Subdural Hematoma after Burr Hole Drainage in a Patient with Chronic Subdural Hematoma and Liver Cirrhosis.

Although acute intracranial bleeding after burr hole drainage for chronic subdural hematoma (SDH) is rare, it could still occur and is associated with a poor clinical outcome. Although rare, most of them occur immediately or within a few days after drainage, especially in patients who are on antiplatelet drugs or anticoagulants. We report an unusual case of delayed-onset acute SDH that developed 14 days after burr hole drainage of chronic SDH in a 54-year-old man with liver cirrhosis and thrombocytopenia. The possible pathophysiological mechanisms of this rare entity are discussed, and the relevant literature is reviewed.

Construction of a T-vector using an esterase reporter for direct cloning of PCR products.

We constructed an efficient T vector pTQEST216T that employed an engineered esterase as an indicator for direct cloning of PCR products. After ligation of the XcmI-digested vector with PCR products, this cloning system could easily discriminate positive clones due to insertional inactivation of the esterase reporter. Additionally, PCR products were cloned into this vector efficiently without the gel purification steps, due to the well-designed multi-cloning site that was in-frame fused at the circularly permutated gap of the reporter.

Extracts of Moringa oleifera leaves from different cultivation regions show both antioxidant and antiobesity activities.

Moringa oleifera is rich in nutrients, such as protein, vitamins, and phytochemicals, and has been used as a traditional remedy. In this study, extracts of M. oleifera leaves from South Korea and Cambodia were evaluated for their antioxidant and antiobesity activities and for food and natural medicine use. The extracts were made using water and ethanol with leaves from South Korea and Cambodia, and then, the ethanol extracts were further fractionated with ethyl acetate. The antioxidant and antiobesity activities of fractionated ethanol extracts were higher than those of water extracts. Although the expression of C/EBPα in 3T3-L1 cell differentiation did not have a concentration-dependent inhibitory effect on the M. oleifera leaf extracts, the expression of PPARγ, FAS, and ACC was inhibited in a concentration-dependent manner with the M. oleifera leaf extracts. This study shows that M. oleifera leaves from South Korea and Cambodia may be an effective candidate for antiobesity prevention. PRACTICAL APPLICATIONS: Antioxidants and antiobesity factors are important for metabolic syndrome including obesity. Recently, natural antiobesity medication containing polyphenol ingredients has been developed to replace synthetic antiobesity medication, which has various side effects. This study evaluates the antioxidant and antiobesity activities of Moringa oleifera leaves from different cultivation regions. The leaves grow rapidly and leaf extracts contain a large amount of nutrients and phytochemicals, which enables commercial production of the leaves as natural antiobesity medications including functional foods and nutraceuticals.

Alginate-Derived Elicitors Enhance ß-Glucan Content and Antioxidant Activities in Culinary and Medicinal Mushroom, Sparassis latifolia.

This study aimed to investigate the elicitation effects of alginate oligosaccharides extracted from brown algae (Sargassum species) on ß-glucan production in cauliflower mushroom (Sparassis latifolia). Sodium alginate was refined from Sargassum fulvellum, S. fusiforme, and S. horneri, and characterized by proton nuclear magnetic resonance spectroscopy (1H NMR), resulting mannuronic acid to guluronic acid (M/G) rationes from 0.64 to 1.38. Three oligosaccharide fractions, ethanol fraction (EF), solid fraction (SF), and liquid fraction (LF), were prepared by acid hydrolysis and analyzed by Fourier transform infrared (FT-IR) spectra and high-performance anion-exchange chromatography with a pulsed amperometric detector (HPAEC-PAD). The samples of S. fusiforme resulted in the highest hydrolysate in SF and the lowest in LF, which was consistent with its highest M/G ratio. The SF of S. fusiforme and LF of S. horneri were chosen for elicitation on S. latifolia, yielding the highest ß-glucan contents of 56.01 ± 3.45% and 59.74 ± 4.49% in the stalk, respectively. Total polyphenol content (TPC) and antioxidant activities (2,2'-Azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) radical scavenging and Superoxide dismutase (SOD)-like activity) of aqueous extracts of S. latifolia were greatly stimulated by alginate elicitation. These results demonstrate that alginate oligosaccharides extracted from brown algae may be useful as an elicitor to enhance the nutritional value of mushrooms.

Antiallergic Effect of Hizikia fusiformis in an Ovalbumin-Induced Allergic Rhinitis Mouse Model.

OBJECTIVES: The extract of Hizikia fusiformis is known to exhibit anticancer, antiatopic and antioxidant activities. We aimed to investigate the extract of H. fusiformis on allergic rhinitis inflammation in a mouse model. METHODS: The 4-week-old BALB/c mice were randomly assigned into four groups: group A, control group (n=9); group B, allergic rhinitis group (n=10); group C (n=10) received 300 mg/kg of H. fusiformis during nasal challenging period; group D (n=10) received 600 mg/kg of H. fusiformis during general sensitization period and 300 mg/kg of H. fusiformis during nasal challenging period. Allergic inflammation was made with ovalbumin (OVA) and alum then challenged intranasally with OVA. H. fusiformis was intraperitoneally administered 3 hours before the OVA administration. Allergic symptom score and the levels of immunoglobulin G1 (IgG1), IgG2a, OVA-specific IgE antibodies, levels of cytokines in the nasal mucosa and in spleen cell culture supernatant, such as tumor necrosis factor alpha (TNF-α), interleukin 4 (IL-4), IL-5, IL-13, and IL-10 were assessed. The percentage of regulatory T cell was analyzed by flow cytometry. Eosinophilic infiltration and goblet cell hyperplasia were also evaluated. RESULTS: H. fusiformis administered groups C and D showed significant inhibitory effects on nasal symptoms, IL-13 mRNA expression and eosinophil infiltration/goblet cell hyperplasia in the nasal tissue; OVA-specific IgE production in serum (P<0.05). In group D, H. fusiformis treatment downregulated IL-4, IL-5, IL-13, TNF-α, and IL-10 cytokine expression in splenocyte culture as well as significantly decreased IgG2a, IgG1 levels in serum compared with group B (P<0.05). However, the expressions of IL-5, interferon-γ and forkhead box P3 mRNA did not change in groups C and D. CONCLUSION: H. fusiformis could induce antiallergic inflammation by suppressing the T-helper type 2 cytokine production (IL-13) locally and systemically, OVA-specific IgE formation, goblet cell hyperplasia, and eosinophilic infiltration in a mouse model of allergic rhinitis. Thus, H. fusiformis could be considered as a potential therapeutic agent in treating allergic rhinitis.

Bamboo Stems (Phyllostachys nigra variety henosis) Containing Polyphenol Mixtures Activate Nrf2 and Attenuate Phenylhydrazine-Induced Oxidative Stress and Liver Injury.

This study was designed to investigate the hepatoprotective effect of bamboo stems using in vitro and in vivo experimental liver damage models. Ethyl acetate fraction of 80% ethanol extract of Phyllostachys nigra stem (PN3) containing polyphenols had a higher NQO1-ARE reporter gene activity as monitored by the activity of the NF-E2-related factor (Nrf2) antioxidant pathway in cells in comparison to extracts from other species and under other conditions. The Nrf2 was translocated from the cytosol to the nucleus in response to PN3, followed by induction of the Nrf2 target gene expression, including HO-1, GCL, and NQO-1 in HepG2 cells. Phosphorylation of Nrf2 in HepG2 cells was enhanced in PN3, which was mediated by PKCδ, ERK, and p38 MAPK. Consequently, PN3 inhibited arachidonic acid (AA) + iron-induced reactive oxygen species generation and glutathione depletion, and, thus, highlighted their role in cytotoxicity. Treatment with major polyphenols of PN3, including catechin, chlorogenic acid, caffeic acid, and p-coumaric acid, also improved AA + iron-mediated oxidative stress and, thus, improved cell viability. Treatment with phenylhydrazine in mice, i.e., the iron overload liver injury model, increased plasma alanine aminotransferase and aspartate aminotransferase levels and changed histological features in mice-a response that was almost completely blocked by PN3 administration. Moreover, PN3 extract mitigated phenylhydrazine-induced oxidative stress and inflammatory responses. Conclusively, PN3 can exert a hepatoprotective effect against iron overload-induced acute liver damage due to its antioxidant properties.

Screening of promoters from metagenomic DNA and their use for the construction of expression vectors.

This study was focused on the screening of valuable genetic resources, such as promoters from metagenome, and describes a promoter trapping system with a bidirectional probe concept, which can select promoters or operons from various biological resources including metagenomic DNA. A pair of reporters, GFP and DsRed, facing the opposite direction without promoters, is an effective system that can function regardless of the direction of inserted promoters. The feasibility of this system was tested for the isolation of constitutively expressed promoters in E. coli from a soil metagenome, resulting in a potential pool of various promoters for practical application. The analyses of structural organization of the trapped genes demonstrated that constitutively expressible promoters in E. coli were broadly distributed within the metagenome, and suggested that some promoters were useful for the construction of expression vectors. Based on these observations, three constitutive promoters were employed in the expression vector system and their potentials for practical application were evaluated in terms of expression level, protein solubility, and effects on host growth.