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Ethyl carbamate (EC) is a known carcinogen, and therefore its intake is regulated internationally. The objectives of this study were to compare the EC recovery yields under different liquid-liquid extraction (LLE) conditions and to investigate the optimum conditions of the aqueous two-phase system (ATPS) for EC extraction. Our results showed that for the LLE method, addition of 15% NaCl improved the EC yield by 15%, and dichloromethane as the extraction solvent showed a slightly higher yield (about 5%) than chloroform. However, there was little difference in the yield when mixing was performed using an ultrasonic bath compared to a vortex mixer. Using response surface methodology with central composite design to analyze the ATPS results, optimal extraction was found to occur at 21.5°C for 2.8 h in the sample containing 70% alcohol and 15% phosphate, showing a recovery yield of 75.64%. This information can be applied to alcoholic beverages and other fermented food products to analyze EC with better extraction methods, depending on the types of food.

Ethyl carbamate (EC) has been identified as a possible human carcinogen belonging to Group 2A. EC is naturally formed during the fermentation and storage of alcoholic drinks and fermented foods. When ingested in large amounts, EC can cause various health problems, such as gastroenteric hemorrhage, vomiting, and cancer. In this study, optimization of EC formation from cyanate was examined using response surface methodology (RSM), a central composite design that includes variables such as alcohol concentration (10, 15, 20, 25, and 30%), pH (2.5, 3.0, 3.5, 4.0, and 4.5), storage temperature (5, 10, 15, 20, and 25°C), and storage duration (2, 4, 6, 8, and 10 days). EC content was determined using gas chromatography with flame ionization detection and the results were optimized using RSM. EC formation from cyanate degradation was found to increase with storage duration and temperature, acidity, and alcohol concentration. Cy-anate degradation was associated with the formation of EC. Approximately 83.1±0.1% of cyanate was degraded to 538±9 μM of EC. However, not all of the cyanate reacted with ethanol during fermentation to form EC. This study aimed to develop the ideal conditions for EC analysis to reduce EC production in alcoholic drinks and fermented foods.

Of the two major speciation modes of endemic plants on oceanic islands, cladogenesis and anagenesis, the latter has been recently emphasized as an effective mechanism for increasing plant diversity in isolated, ecologically homogeneous insular settings. As the only flowering cherry occurring on Ulleung Island in the East Sea (concurrently known as Sea of Japan), Prunus takesimensis Nakai has been presumed to be derived through anagenetic speciation on the island. Based on morphological similarities, P. sargentii Rehder distributed in adjacent continental areas and islands has been suggested as a purported continental progenitor. However, the overall genetic complexity and resultant non-monophyly of closely related flowering cherries have hindered the determination of their phylogenetic relationships as well as the establishment of concrete continental progenitors and insular derivative relationships. Based on extensive sampling of wild flowering cherries, including P. takesimensis and P. sargentii from Ulleung Island and its adjacent areas, the current study revealed the origin and evolution of P. takesimensis using multiple molecular markers. The results of phylogenetic reconstruction and population genetic structure analyses based on single nucleotide polymorphisms detected by multiplexed inter-simple sequence repeat genotyping by sequencing (MIG-seq) and complementary cpDNA haplotypes provided evidence for (1) the monophyly of P. takesimensis; (2) clear genetic differentiation between P. takesimensis (insular derivative) and P. sargentii (continental progenitor); (3) uncertain geographic origin of P. takesimensis, but highly likely via single colonization from the source population of P. sargentii in the Korean Peninsula; (4) no significant reduction in genetic diversity in anagenetically derived insular species, i.e., P. takesimensis, compared to its continental progenitor P. sargentii; (5) no strong population genetic structuring or geographical patterns in the insular derivative species; and (6) MIG-seq method as an effective tool to elucidate the complex evolutionary history of plant groups.

The complete mitogenome of Pseudotolithus typus (Perciformes: Sciaenidae) is analyzed by high-throughput sequencing. The 16,502 nucleotides of assembled mitogenome has 13 protein-coding gen...

Background Adverse events (AEs) not listed on drug labels have recently been reported in young girls vaccinated against HPV, but signal detection related to the human papillomavirus (HPV) vaccine has never been conducted in South Korea using the Korea Adverse Event Reporting System database of Korea Institute of Drug Safety & Risk Management at Ministry of Food and Drug Safety. Objective To analyze signals associated with HPV vaccines using the Korean spontaneous AEs reporting system and data-mining methods and compare the results to current vaccine label information in South Korea and the United States of America, United Kingdom, European Union, and Japan to detect signals not currently listed on the labels. Setting We evaluated the Korea Institute of Drug Safety & Risk Management database from January 2005 to December 2016. After pre-screening the data, the adjusted total numbers of HPV-related AE reports and AEs were 2566 and 4748 and those of all other vaccine-related AE reports and AEs were 21,878 and 120,688, respectively. Methods Three data mining algorithms (proportional reporting ratio, reporting odds ratio and information component) were used to assess AEs. A signal was defined when the criteria for all three indicators were satisfied. The detected signals were compared to the label information of HPV vaccines from South Korea, the United States of America, United Kingdom, European Union, and Japan. Main outcome measure Signals of AE after HPV vaccination, which met all three data mining indices. Results In this study, we found a total 97 signals of AE after HPV vaccination. Of these, 78 AEs were already present on the HPV vaccine labels of South Korea and the following 19 AEs were not listed: neuralgia, tremor, neuritis, depersonalization, axillary pain, personality disorder, increased salivation, peptic ulcer, circulatory failure, hypotension, peripheral ischemia, cerebral hemorrhage, micturition disorder, facial edema, ovarian cyst, weight increase, pain anxiety, oral edema, and back pain. Moreover, AE information on the current HPV vaccine labels of South Korea, the United States of America, United Kingdom, European Union, and Japan was inconsistent. When comparing the 19 AE signals that were not listed on the drug label in South Korea with the labels from the other countries, neuritis, axillary pain, cerebral hemorrhage, facial edema, pain anxiety, and back pain appreared on the U.S. Food and Drug Administration HPV vaccine labels but not on the United Kingdom labels, and hypotension was listed only on labels in the European Union and Japan. Conclusions South Korea should develop a system for proactively updating HPV labels. These results also suggest potential research directions such as vaccination label expansion, pharmacovigilance studies, and identification of causality in AEs associated with HPV vaccination.

Prunus takesimensis is an endemic flowering cherry on Ulleung Island, Korea. The complete chloroplast (cp) genome of P. takesimensis was generated by de novo assembly using whole-genome next-generation sequencing approach. The cp genome size was 157,948 bp in length consisting of four regions; large single copy region (85,959 bp), small single copy region (19,117 bp), and a pair of inverted repeat regions (26,436 bp). The genome contained a total of 128 genes, including 83 coding genes, 8 rRNA genes, and 37 tRNA genes. Phylogenetic analysis for 20 reported genomes within the family Rosaceae showed the monophyly of the genus Prunus including newly sequenced P. takesimensis.

The first complete chloroplast genome sequences of Korean endemic basswood in Ulleung Island, Tilia insularis, were reported in this study. The T. insularis plastome was 162,565 bp long, with the large single-copy (LSC) region of 91,100 bp, the small single-copy (SSC) region of 20,381 bp, and two inverted repeat (IR) regions of 25,542 bp. The plastome contained 131 genes, including 86 protein-coding, eight ribosomal RNA, and 37 transfer RNA genes. The overall GC content was 36.5%. Phylogenetic analysis of 14 representative plastomes within the family Malvaceae suggests that T. insularis is closely related to other congeneric species in subfamily Tilioideae.

The complete mitochondrial genome of pitted stingray, Bathytoshia brevicaudata (Myliobatiformes: Dasyatoidea) was investigated by next-generation sequencing. The analyzed mitochondrial genome was 17,640 nucleotides in length and had 59.2% for AT contents. This genome contains 2 ribosomal RNA genes, 13 protein-coding genes, 22 transfer RNA genes. and 1 putative control region. Five protein-coding genes (ATPase6, COII, ND2, ND3, ND4) including incomplete stop codons and four tRNAs have atypical codons. The phylogenetic inference including 13 species of the same family revealed a close relationship with Pteroplatytrygon violacea. This is the first mitochondrial genome report from genus Bathytoshia.

The complete mitochondrial genome of Pseudotolithus elongatus (Perciformes: Sciaenidae) is determined based on NGS technology. The assembled mitogenome is a 16,497 bp in length containing a typical set of the 13 protein-coding genes, 22 tRNAs, 2 rRNA genes, and the 1 putative control region. The overall base composition is A (27.8%), T (25.3%), G (16.1%), and C (30.8%) with an A-T content of 53.1%. The phylogenetic analysis of 36 mitogenomes from the GenBank indicated that P. elongatus is closely related to the Aplodinotus grunniens. This mitogenome information of the P. elongatus would be useful to understand evolutionary and phylogenetic analysis of the family Sciaenidae fishes.

Commercially available tunas and billfishes are generally processed as steaks, making it difficult to visually distinguish between the two. We developed and validated species-specific primers to prevent the adulteration of tunas by billfishes. Tunas and billfishes primers were designed on the cytochrome oxidase subunit I. Multiplex PCR bands obtained were 579 bp, 291 bp and 114 bp for tunas, billfishes and internal control. Sensitivity was determined to be 5 ng for tunas and billfishes. A total of 50 samples were monitored: 49 for tunas and 1 for billfish. As a result of the monitoring, the fake tunas did not show due to the agreement between product name and the raw material of the wrapping paper. Our results indicate that the species-specific primers developed in this study are suitable for differentiating tunas and billfishes. The newly developed multiplex PCR assay is a time and cost effective technique for determining the authenticity of tunas and billfishes.

Previous phylogenetic studies have suggested that Rubus takesimensis (Rosaceae), which is endemic to Ulleung Island, Korea, is closely related to R. crataegifolius, which is broadly distributed across East Asia. A recent phylogeographic study also suggested the possible polyphyletic origins of R. takesimensis from multiple source populations of its continental progenitor R. crataegifolius in China, Japan, Korea, and the Russian Far East. However, even though the progenitor-derivative relationship between R. crataegifolius and R. takesimensis has been established, little is known about the chloroplast genome (i.e., plastome) evolution of anagenetically derived species on oceanic islands and their continental progenitor species. In the present study, we characterized the complete plastome of R. takesimensis and compared it to those of R. crataegifolius and four other Rubus species. The R. takesimensis plastome was 155,760 base pairs (bp) long, a total of 46 bp longer than the plastome of R. crataegifolius (28 from LSC and 18 from SSC). No structural or content rearrangements were found between the species pairs. Four highly variable intergenic regions (rpl32/trnL, rps4/trnT, trnT/trnL, and psbZ/trnG) were identified between R. takesimensis and R. crataegifolius. Compared to the plastomes of other congeneric species (R. corchorifolius, R. fockeanus, and R. niveus), six highly variable intergenic regions (ndhC/psaC, rps16/trnQ, trnK/rps16, trnL/trnF, trnM/atpE, and trnQ/psbK) were also identified. A total of 116 simple sequence repeats (SSRs), including 48 mononucleotide, 64 dinucleotide, and four trinucleotide repeat motifs were characterized in R. takesimensis. The plastome resources generated by the present study will help to elucidate plastome evolution within the genus and to resolve phylogenetic relationships within highly complex and reticulated lineages. Phylogenetic analysis supported both the monophyly of Rubus and the sister relationship between R. crataegifolius and R. takesimensis.

The complete mitochondrial genome of Pseudotolithus elongatus (Perciformes: Sciaenidae) is determined based on NGS technology. The assembled mitogenome is a 16,497 bp in length containing a typical...

Country-of-origin violations have occurred in which some merchants have fraudulently sold cheap Japanese yellowtail (Seriola quinqueradiata) by presenting them as domestic Korean products. There are many methods for determining the origins of marine organisms, such as molecular genetic methods and isotope analysis. However, this study aimed to develop a method for determining the origins of aquatic products using metabolite analysis technology. Ten yellowtail each from Korea and Japan were analyzed by capillary electrophoresis–time of flight/mass spectrometry (CETOF/MS). Hierarchical cluster analysis (HCA) and principal component analysis (PCA) results showed highly differing aspects between the Korean and Japanese samples. In the tricarboxylic acid (TCA) cycle, citric, malic, oxaloglutaric, and fumaric acids exhibited significant differences between Korean and Japanese yellowtail. Sixteen of the twenty essential amino acids analyzed as metabolites also differed significantly. All amino acids were involved in protein digestion, absorption, and metabolism. All 16 amino acid contents were higher in Japanese yellowtail than in Korean yellowtail, except for glutamine. The fasting period was found to be the biggest factor contributing to the difference in amino acid contents, in addition to environmental factors (including feeding habits). These significant differences indicated that metabolomics could be used to determine geographical origin.

Halocynthia aurantium (Stolidobranchia: Pyuridae) is a species of tunicate of commercial value that is commonly found in the northern Pacific Ocean and in the Bering Sea. Here, we determined the complete mitogenome of sea peach H. aurantium using 150 PE high-throughput sequencing. The assembled mitogenome is 14,979 bp in length (overall A + T contents 56.2%), and contains 13 protein-coding genes, 21 transfer RNAs, two ribosomal RNAs. Phylogenetic analysis of the mitogenome sequence of H. aurantium fully resolved it in a clade with H. roretzi. These data and results will be useful for future studies on the evolution of the Halocynthia and the Pyuridae.

Two major modes of speciation, i.e., cladogenesis and anagenesis, have often been used to explain the generation of distinct plant diversity on oceanic islands. Anagenetic speciation is of particular interest to plant endemics on Ulleung Island, Korea because, of nearly 40 endemics, approximately 88% or even all endemic species are thought to be anagenetically derived. Despite its important role in Ulleung Island, the full scope of the anagenetic speciation and the genetic consequences of this speciation mode have been limited to a very few families (i.e., Apiaceae, Sapindaceae, and Ranunculaceae). Based on extensive sampling (a total of 322 individuals) and trnL-F cpDNA noncoding sequences, we conducted phylogenetic and haplotype network analyses for the species pair of Rubus crataegifolius (continental progenitor)-R. takesimensis (insular derivative). Rubus takesimensis on Ulleung Island is not a monophyletic group, suggesting at least two independent introductions from geographically and genetically divergent source populations. No significant reduction in cpDNA haplotype diversity and genetic differentiation in R. takesimensis are consistent with expectations from the anagenetically derived species. A further study based on comprehensive sampling and more variable molecular markers will shed light into the genetic consequences of anagenetic speciation in Rubus on Ulleung Island.

The complete mitochondrial genome of pitted stingray, Bathytoshia brevicaudata (Myliobatiformes: Dasyatoidea) was investigated by next-generation sequencing. The analyzed mitochondrial genome was 17,640 nucleotides in length and had 59.2% for AT contents. This genome contains 2 ribosomal RNA genes, 13 protein-coding genes, 22 transfer RNA genes. and 1 putative control region. Five protein-coding genes (ATPase6, COII, ND2, ND3, ND4) including incomplete stop codons and four tRNAs have atypical codons. The phylogenetic inference including 13 species of the same family revealed a close relationship with Pteroplatytrygon violacea. This is the first mitochondrial genome report from genus Bathytoshia.

The complete mitochondrial genome of smallscale blackfish, Girella melanichthys (Perciformes: Kyphosidae), was analyzed using MGISEQ-2000 platform. The assembled mitogenome had 16,518 nucleotides (...

Symplocarpus, a skunk cabbage genus, includes two sister groups, which are drastically different in life history traits and thermogenesis, as follows: The nonthermogenic summer flowering S. nipponicus and thermogenic early spring flowering S. renifolius. Although the molecular basis of thermogenesis and complete chloroplast genome (plastome) of thermogenic S. renifolius have been well characterized, very little is known for that of S. nipponicus. We sequenced the complete plastomes of S. nipponicus sampled from Japan and Korea and compared them with that of S. renifolius sampled from Korea. The nonthermogenic S. nipponicus plastomes from Japan and Korea had 158,322 and 158,508 base pairs, respectively, which were slightly shorter than the thermogenic plastome of S. renifolius. No structural or content rearrangements between the species pairs were found. Six highly variable noncoding regions (psbC/trnS, petA/psbJ, trnS/trnG, trnC/petN, ycf4/cemA, and rpl3/rpl22) were identified between S. nipponicus and S. renifolius and 14 hot-spot regions were also identified at the subfamily level. We found a similar total number of SSR (simple sequence repeat) motifs in two accessions of S. nipponicus sampled from Japan and Korea. Phylogenetic analysis supported the basal position of subfamily Orontioideae and the monophyly of genus Symplocarpus, and also revealed an unexpected evolutionary relationship between S. nipponicus and S. renifolius.

The woody Sonchus alliance consists primarily of woody species of the genus Sonchus (subgenus Dendrosonchus, family Asteraceae). Most members of the alliance are endemic to the oceanic archipelagos in the phytogeographic region of Macaronesia. They display extensive morphological, ecological, and anatomical diversity, likely caused by the diverse habitats on islands and rapid adaptive radiation. As a premier example of adaptive radiation and insular woodiness of species endemic to oceanic islands, the alliance has been the subject of intensive evolutionary studies. While phylogenetic studies suggested that it is monophyletic and its major lineages radiated rapidly early in the evolutionary history of this group, genetic mechanisms of speciation and genomic evolution within the alliance remain to be investigated. We first attempted to address chloroplast (cp) genome evolution by conducting comparative genomic analysis of three representative endemic species (Sonchus acaulis, Sonchus canariensis, and Sonchus webbii) from the Canary Islands. Despite extensive morphological, anatomical, and ecological differences among them, their cp genomes were highly conserved in gene order and content, ranging from 152,071 to 152,194 bp in total length. The number of repeat variations and six highly variable regions were identified as valuable molecular markers. Phylogenetic analysis of 32 species in the family Asteraceae revealed the phylogenetic position of the woody Sonchus alliance within the tribe Cichorieae and the sister relationship between the weedy Sonchus oleraceus and the alliance.

Four names by T. Nakai are validly established within Korean Rubus L. (Rosaceae). The invalid name “R. coreanus Miq. var. concolor Nakai” is newly described as R. coreanus var. concolor Nakai ex J. Y. Yang from Gyeongsangnam-do Province in southeastern Korea. The invalid name “R. phoenicolasius Maxim. var. albiflorus Nakai” is newly described as R. phoenicolasius var. albiflorus Nakai ex J. Y. Yang from Jellanam-do Province in southwestern Korea. The invalid name “R. tozawai Nakai” is corrected for its epithet and newly described as R. tozawae Nakai ex J. Y. Yang from southeastern Korea. The new variety R. tozawae var. longisepalus J. Y. Yang is described from Gyeongsangnam-do Province in southeastern Korea. Lectotypes are designated for R. coreanus, R. coreanus var. nakaianus H. Lev., and R. quelpaertensis H. Lev.

Background We investigated the effects of corticosteroids on the 90-day mortality outcomes in patients with pulmonary tuberculosis who were admitted to the intensive care unit (ICU) because of acute respiratory failure (ARF). Methods The medical records of 124 patients who had pulmonary tuberculosis with ARF and were admitted to the ICU at our tertiary referral center in South Korea between March 1989 and December 2014 were retrospectively analyzed. The 90-day mortality rate in this population was analyzed after adjustments with the inverse probability of treatment weighted (IPTW) method. Results The mean patient age was 62 years, and the 90-day mortality rate was 49.2% (61/124). Adjuvant steroids were used in 70 (56.5%) patients. The 90-day mortality rate was similar irrespective of corticosteroid use (48.6%, steroid group; 50.0%, nonsteroid group). The use of adjuvant steroids was not associated with the unadjusted 90-day mortality (odds ratio [OR], 0.94; 95% confidence interval [CI], .46-1.92; P = .875). In a comparison using an adjusted IPTW approach of the 90-day mortality between the 2 groups, we found that corticosteroid use was independently associated with reduced 90-day mortality (OR, 0.47; 95% CI, .22-.98; P = .049). Conclusions The study results showed that corticosteroids could reduce the 90-day mortality rate in critically ill pulmonary tuberculosis patients with ARF.

The first complete chloroplast genome sequence of Korean insular endemic to Ulleung-do Island, Zabelia insularis, was reported in this study. The plastome size was 158,100 bp in total length, with one large single copy (90,529 bp), one small single copy (17,235 bp), and two inverted repeat (IR) regions (IRa and IRb, each with 25,168 bp). The overall GC content was 38.3% and the genome contained 130 genes, including 83 protein-coding, 37 transfer RNA, and 8 ribosomal RNA genes. Phylogenetic analysis of 15 representative plastomes within the Caprifoliaceae suggests that Z. insularis is closely related to the species in the genus Patrinia.