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This study investigated the potential of a novel fabricated black phosphorus (BP) nanoparticle electrode as an alternative to noble metal-based catalysts for application in electrolysis. The BP electrode was compared with other conventional catalysts (boron-doped diamond (BDD) and a dimensional stable electrode (DSA)) under different electrolyte conditions for the generation of specific oxidants (e.g., OH

Flow-electrode capacitive deionization (FCDI) is a new electrochemical-based desalination technology that addresses the limitations of preceding CDI processes through the use of a stationary carbon electrode and ion-exchange membrane. As with conventional CDI configurations, non-Faradaic reactions (i.e., ion electrosorption) of the electric double layer model is the principal ion separation mechanism of FCDI. This technology also offers the unique ability for continuous ion/salt separation by circumventing constraints with electrode saturation. This paper reviews recent advances in FCDI, discusses the feasibility and applicability of this technique, and suggests potential niche applications for saline water/wastewater treatment and resource recovery. Additionally, it also critically discusses factors that deteriorate FCDI performance, operating conditions, process energy efficiency, and optimization of the electrode, electrolyte, and cell design. The insights from this review will shed light on directions for future FCDI research and inform the implementation of FCDI technology.

Escherichia coli has been a primary host for the prokaryotic production of antibody fragments (Fabs) and has contributed to several successes in the pharmaceutical industry. Nevertheless, the requirement of disulfide bonds often results in low-yield fermentation and a lack of cost-effectiveness. Despite the improved production of functional Fabs by fermentation below 30 °C, the limited cellular growth needs further work. To address these issues, we investigated the effect of nitrogen supply on the cellular growth and the Fab productivity. We used the anti-human VEGF-A Fab as a model that exhibited poor expression at 37 °C regardless of the amount of nitrogen supplied during fermentation. In stark contrast, the expression yield of soluble Fab with a gross nitrogen supply of 6.91 g/L of broth throughout the fermentation at 25 °C was 332 mg/L. Furthermore, and increased nitrogen supply of 10.9 g/L significantly improved the yield of active form by 59.7% and the cellular growth rate by 39.3%. These results indicate that overdosing of a nitrogen source at low temperature is critical to Fab productivity in E. coli.

l-Methionine has been used in various industrial applications such as the production of feed and food additives and has been used as a raw material for medical supplies and drugs. It functions not only as an essential amino acid but also as a physiological effector, for example, by inhibiting fat accumulation and enhancing immune response. Producing methionine from fermentation is beneficial in that microorganisms can produce l-methionine selectively using eco-sustainable processes. Nevertheless, the fermentative method has not been used on an industrial scale because it is not competitive economically compared with chemical synthesis methods. Presented are efforts to develop suitable strains, engineered enzymes, and alternative process of producing l-methionine that overcomes problems of conventional fermentation methods. One of the alternative processes is a two-step process in which the l-methionine precursor is produced by fermentation and then converted to l-methionine by enzymes. Directed efforts toward strain development and enhanced enzyme engineering will advance industrial production of l-methionine based on fermentation.

To acquaint correct information about the fertilizability and analyze S-allele based genetic diversity among Korean apples, we investigated self-incompatibility genotypes by PCR and cross-pollination tests in field. As a consequence, S-genotypes of Korean apples were distributed within narrow genetic diversity as S1S3 for ‘Hongro’ and ‘Saenara’; S1S9 for ‘Gamhong’ and ‘Manbok’; S3S5 for ‘Seokwang’; S3S9 for ‘Sunhong’, ‘Seohong’, ‘Chukwang’, and ‘Hwahong’. Coupled with cross-pollination experiments in field, our results provide support for the view that apples are fully compatible when both of their S-loci differ and semi-compatible when they carry one different and one identical S-locus. Furthermore, the results of this study indicate that S-alleles have to be extended to various genotypes for Korean apple breeding.

A new cultivar ‘Yeohong’ was originated from an artificial cross between ‘Jonathan’ and ‘Fuji’ carried out at National Institute of Horticultural & Herbal Science in 1993. The cultivar was preliminarily selected among the elite siblings for its high fruit quality in 2002. After regional adaptability test at five districts for subsequent four years as ‘Wonkyo Ga-31’, it was finally selected in 2007. ‘Yeohong’ is characterized by the following. Optimum harvest time is late September. Shape of mature fruit at 278 g on mean weight is oblate a light red skin on a greenish yellow ground and yellowish white flesh. The fruit contains favorable total soluble solids at 14.3 °Brix and titratable acidity at 0.4%, which results in a gustatory harmony between sugars and acids. Safe storage period for the fruit is 3 weeks at room temperature. It is not resistant to Bitter rot. ‘Yeohong’ also reveals a physiological cross compatibility with leading cultivars such as ‘Hongro’ and ‘Tsugaru’, but a physiological cross incompatibility with ‘Fuji’. It has weak growth habit.

The conventional method to identify pear tree cultivars is to evaluate the morphological characteristics of the trunk, leaves, flowers, and fruit. However, it is difficult to distinguish between the closely related pear cultivars using only morphological traits, particularly if the cultivars to be compared share the same pedigree. Thus, we developed more reliable DNA markers to identify 39 pear cultivars bred in Korea and Japan. In total, 147 random amplified polymorphic DNA (RAPD) markers were developed from 40 different random primers. The resulting 51 RAPD fragments were selected, and their sequences were determined to convert them into sequence-characterized amplified region (SCAR) markers. As a result, 19 of 51 RAPD fragments were successfully converted to SCAR markers. A single polymorphic band of the same size as the RAPD fragments or smaller DNA fragments were amplified depending on primer combinations in the 17 SCAR markers, and co-dominant polymorphisms were observed using two of the SCAR markers (named PK10_514 and PK15_616). A combination of eight SCAR markers (P561_331, P561_372, PH02_405, PH15_ 452, PT16_472, PK10_514, P270_593, and PK15_616) provided sufficient polymorphisms to identify 25 Korean pear cultivars among the 39 pear cultivars tested. A combination of nine SCAR markers (P561_331, P561_372, PH02_ 405, PH15_452, PT16_472, PT14_578, P270_593, PK10_514, and PK15_616) could be used to sufficiently distinguish among the 39 pear cultivars examined in this study. These newly developed markers will be useful as a fast and reliable tool to identify Korean pear cultivars.

To prevent self-fertilization, apple has a gametophytic self-incompatibility mechanism, part of a widespread intraspecific system, that is controlled by a multi-allelic locus. This attribute has been exploited in breeding programs for new cultivars. Likewise, many apple orchards depend on artificial pollination. Therefore, molecular analysis and early identification of the self-incompatibility (S) genotype could greatly improve breeding schemes and pollen donors selection. Here, we PCR-amplified the S-RNase PCR fragments from a total of 14 cultivars and parents, using new primers (ASPF3+ASPR3) common to 23 S-alleles in apple. The S-genotypes were determined for the following: ‘Hongro’ (S1S3), ‘Gamhong’ (S1S9), ‘Saenara’ (S1S3), ‘Chukwang’ (S3S9), ‘Hwahong’ (S3S9), ‘Seokwang’ (S3S3), ‘Hwarang’ (S1S9), ‘Sunhong’ (S3S9), ‘S.E.B.’ (S1S19), ‘S.G.D.’ (S2S3), and ‘Mollie’s Delicious’ (S3S7). We also confirmed the characteristics of the S-genotypes for eight Korean apple cultivars by PCR-Southern blot analysis, using seven S-RNases as probes.

The pear cultivar ‘Osa-Nijisseiki’ (S2Ssm 4; sm = stylar-part mutant) has been used as a parent to breed self-compatible cultivars that produce excellent fruits. However, determination of the self-compatibility of ‘Osa-Nijisseiki’ offspring requires a lot of time, 6 years or more, by conventional cross breeding. We have designed a rapid reliable method for the identification of self-compatible varieties of ‘Osa-Nijisseiki’ offspring based on the polymerase chain reaction (PCR) and restriction fragment length polymorphism (RFLP) with S-allele specific restriction endonucleases. By using this method, 8 self-compatible varieties were selected among 16 selections resulting from a cross between the self-compatible cultivar ‘Osa-Nijisseiki’ (S2Ssm 4) and the self-incompatible cultivars ‘Niitaka’ (S3S9), ‘Whasan’ (S3S5), ‘Chuwhangbae’ (S4S6). The S-genotypes of 16 ‘Osa-Nijisseiki’ offsprings were also determined.

We isolated four cDNAs encoding different isoforms of NAD–SDH from Malus x domestica cv. Fuji. The derived amino acid sequences of MdSDH1 , MdSDH2 , MdSDH3 , and MdSDH4 have considerable homology with NAD–SDHs from human, rat, and sheep. MdSDH1 is almost identical with the previously reported apple NAD – SDH . MdSDH2 , MdSDH3 , and MdSDH4 are clearly distinguished from MdSDH1 based on the primary structure, showing 69–71% identity with MdSDH1 and 90–92% identity with each other. The expression of MdSDH2 , MdSDH3 , and MdSDH4 is restricted to sink tissues including young leaves, stems, roots, and maturing fruits, implying their relationship with the sink activity of apple tissues. Unlike the others, MdSDH1 is highly expressed in source leaves as well as young leaves, indicating that the expression of MdSDH1 is not restricted to sink tissues. During the fruit development, four SDH genes are highly expressed at the late stage, suggesting that they play an important role in the period of fruit maturation rather than in the early stage of fruit development. MdSDH2 and MdSDH3 fusion proteins expressed in Escherichia coli cells exhibit NAD–SDH activity in both direction, but not NADP-SDH activity. The present study indicates that MdSDH1 , MdSDH2 , MdSDH3 , and MdSDH4 encode the novel isoforms of NAD-dependent sorbitol dehydrogenase categorized to two independent phylogenetic groups.

The gene, vapK, encoding an extracellular alkaline protease, VapK, in Vibrio metschnikovii strain RH530 was cloned and expressed in Escherichia coli. The nucleotide sequence of the vapK revealed a single open reading frame of 1266 bp encoding 422 amino acids. The biochemical characteristics of the expressed protease were indistinguishable from those of VapK from the wild type strain. The recombinant VapK showed resistant activity to surfactants such as sodium α-olefin sulfonate, polyoxyethylene oxide, SDS and urea. The surfactant, sodium alkylbenzenesulfonate, strongly inhibited the activity of re-VapK. However in the presence of POE or Na2SO4, its activity was completely restored. By N-terminal sequencing of VapK, the cleavage site for the mature protease could be identified. The cleavage site was Ala140 and the calculated molecular mass of the mature enzyme was 29 609 Da, corresponding to the purified VapK. The active sites and putative calcium binding sites of recombinant VapK (re-VapK) were highly conserved when compared to subtilisin Carlsberg.

A fruit-specific and pathogenesis-related 5/thaumatin-like (PR5/TL), 31-kDa protein was isolated by 2D-PAGE from fully-grown apples (Malus domestica cv. Fuji) and named Mdtl1 (Malus domestica thaumatin-like protein 1). Using the N-terminal sequence of the protein, the full-length cDNA encoding Mdtll was isolated. The cDNA clone (Mdtl1) consists of 944 bp with an open reading frame (ORF) of 744 bp encoding a protein of 247 amino acids. The deduced amino acid sequence of Mdtl1 shows high similarity to the sequences of PR5/TL proteins. Mdtl1 is a slightly acidic protein with a putative signal peptide and a putative N-glycosylation site, and lacks a C-terminal extension. This suggests that Mdtl1 is an apoplastic glycoprotein. Results of northern blotting indicated that expressions of Mdtl1 are developmentally regulated. Southern blot analysis showed that Mdtl1 may be present as a single copy, and there exist other genes closely related to Mdtl1 in the apple genome.

‘Seohong’ is an early-maturing cultivar with high levels of antioxidant phytochemicals and a much longer shelf life than ‘Gala’. The fruit has a greenish yellow ground color and a medium red blush over the whole fruit. It is medium to large-sized and has an excellent appearance and outstanding flavor. The flesh is extremely juicy and sweet and retains crispness and juiciness for 2 weeks at room temperature. It ripens 1 week later than ‘Tsugaru’ and is harvested in late August in Korea. The tree is moderately vigorous, spreading, semispur type with productive and regular bearing. It is not subject to alternate bearing when proper thinning is performed but has some preharvest drop. A plant patent was granted in 2007, and the cultivar will be marketed under the trade name ‘Seohong’ to emphasize its early maturing and red color.