Because intact FMDV particles (146S) are often unstable in vitro, stabilizing foot-and-mouth disease virus (FMDV) antigens remains a key challenge in studying viral charateristics. Therefore, finding optimal condition to stabilize the FMDV is essential. In this study, we investigated formulations and potentials of several stabilizers such as appropriate buffer, excipients, and storage conditions to enhance the stability of 146S. Inactivated FMDV O-Jincheon (O-JC) was dissolved in various buffer formulations, and stored at 4℃ for two months to evaluate quantity of 146S at every 2-week interval. Among phosphate buffered saline (PBS), Tris buffered saline (TBS), HEPES buffered saline (HBS), and MOPS buffered saline (MBS), PBS showed more effective 146S stabilization that showed 1.3-1.6 fold higher 146S fraction than TBS, HBS, and MBS after storage for 2 weeks. However, constant dissociations of 146S were observed in all formulations at 8 weeks. Compared with other FMDVs, A22 Iraq and SAT-1, in PBS, O-JC proved to be the least stable in PBS. A variety of excipients including carbohydrate, sugar alcohol, cryo-protectant were tested for the capability in protecting O-JC from dissociation. By adding 4-8% sucrose, more than 60% of 146S fractions were maintained at 8 weeks, those were at least 1.8 fold higher than the PBS-only control. Addition of 1% β-cyclodextrin showed synergistic enhancement in O-JC stability. As the results of this study, it could be suggested that the PBS-based buffer together with 4-8% sucrose + 2% sorbitol or 2% sucrose + 2% sorbitol + 1% β-cyclodextrin could help the better stability of the O-JC in vaccine preparation.

Foot-and-mouth disease (FMD), which affects cloven-hoofed animals, is economically important because of its highly contagious nature. FMD virus (FMDV), the causative agent of FMD, involves seven serotypes (O, A, Asia1, C, and SAT 1-3). Serotype Asia1 is unique to the Asian territory and is subdivided into nine genetic groups (G-I-IX) based on nucleotide variations in the VP1 sequence. Asia1 Shamir, the most representative Asia1 vaccine, is not highly protective against the Asia1/MOG/05 (G-V) lineage found in North Korea in 2007. Therefore, we investigated whether a chimeric virus strain (Asia1/MOG/Shamir), in which the VP4, VP2, and VP3 sequences of Asia1/MOG/05 were combined with the VP1 sequence of Asia1 Shamir, can simultaneously protect against both viruses. We determined the optimal viral growth conditions for the commercial utilization of this chimeric virus strain. Of the three types of cell culture media, the Cellvento medium resulted in the highest amount of antigen in the samples. The chimeric strain was proliferated in a small bioreactor to produce a test vaccine, and its immunogenicity was evaluated in pigs. The virus neutralization (VN) titer against the Asia1 Shamir virus was > 1/100 after the second immunization with the chimeric vaccine in pigs. In addition, a single dose of the test vaccine resulted in a VN titer of > 1/100 against the Asia1/MOG/05 strain. Taken together, our chimeric vaccine strain provided sufficient protection against the Asia1/MOG/05 and Asia1 Shamir viruses, suggesting its potential as a novel vaccine for both these strains.

Foot-and-mouth disease (FMD) is a highly contagious vesicular disease that affects cloven-hoofed animals, causing substantial economic losses to the livestock industry. The causative FMD virus (FMDV) comprises four structural proteins (VP1, VP2, VP3, and VP4) and several non-structural proteins. Among the capsid proteins, VP4 is the most conserved, making it an attractive target as a diagnostic and vaccine antigen, regardless of FMDV serotype. In this study, we attempted to express the VP4 protein N-terminally fused to a glutathione S-transferase (GST) tag in Escherichia coli. Whereas VP0 and VP2 proteins were expressed in the soluble fraction, we failed to detect VP4, even in the insoluble fraction. To investigate the effect of VP4 C-terminal amino acid residues on protein expression, we constructed three VP4 mutants fused to GST, among which the mutant in which the C-terminal 15 amino acid residues had been deleted showed the highest level of protein expression. Furthermore, protein expression was observed even in the mutant in which three amino acid residues (DKK) had been fused to the C terminus. However, unlike the other two mutants, the wild-type VP4 mutant was poorly expressed, thereby indicating that the C-terminal amino acid residues could play a pivotal role in determining expression of the VP4 protein in E. coli.

In our previous study, active-single compound (ASC), inhibitor of melanogenesis in B16F10 melanoma cell, was identified from Ganoderma lucidum. Thus, the aim of this study is to analyze the change of the ASC contents in G. lucidum when lacquer tree (LT) was added in cultivation of G. lucidum. In HPLC analysis, significantly increased ASC peak was observed in G. lucidum extract supplemented with 15% (v/v) of LT. In addition, melanogenesis inhibitory effect of G. lucidum extract supplemented with 15% of LT significantly increased when compared to G. lucidum extract without LT supplementation. Furthermore, LT supplementation increased mycelial growth of G. lucidum in both solid and liquid cultivation. These results suggest that is useful as natural ingredient for increasing bioactivity including skin-whitening effect and mycelial growth of G. lucidum.

In our previous study, active-single compound (ASC), inhibitor of melanogenesis in B16F10 melanoma cell, was identified from Ganoderma lucidum. Thus, the aim of this study is to analyze the change of the ASC contents in G. lucidum when oriental raisin tree (ORT) was added in cultivation of G. lucidum. In HPLC analysis, significantly increased ASC peak was observed in G. lucidum extract supplemented with 15% (v/v) of ORT. In addition, melanogenesis inhibitory effect of G. lucidum extract supplemented with 15% of ORT significantly increased when compared to G. lucidum extract without ORT supplementation. Furthermore, ORT supplementation increased mycelial growth of G. lucidum in both solid and liquid cultivation. These results suggest that oriental raisin tree is useful as natural ingredient for increasing bioactivity including skin-whitening effect and mycelial growth of G. lucidum.

LB-Deck is one of the widely used member in interior part of girders as a permanent formwork in structures, but it is not easy to apply to the exterior part of girder due to the overturning and excessive deflection. Considering allowable deflection and safety of the exterior part, Precast Concrete Cantilever Deck (PCC-Deck) is proposed with normal LB-Deck in inner part and extended bars of LB-Deck in outer part. Both numerical analyses and experimental tests were compared to check the safety and allowable deflection for 6 types of PCC-Deck, and D-type (with 16 mm top bar, 6 mm lattice bar, 12 mm bottom bar) is suggested as an optimal structural reinforcement to the 28 kN of maximum load and 27.49 mm of final deflection. The load resisting ratio of D-type under working load of 10 kN was about 2.8 times and 77.5% of improvement was observed.