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Although metal‐organic framework (MOF)‐derived nanoporous C (NPC) materials offer several advantages for electrochemical sensor applications, surface functionalization and porosity tuning can affect sensor performance. This study presents the development of a skin patch for perspiration and electrocardiogram (ECG) monitoring, leveraging the unique properties of MOF‐on‐MOF‐derived surface‐functionalized hybrid nanoporous C (f‐HNPC) incorporated into laser‐scribed graphene (LSG). Hydroxyl (OH) group‐functionalized NPC, achieved through KOH activation, facilitates electron transport at the electrode–electrolyte interface. This enhances the electrochemical activity, thereby improving sensor sensitivity and expanding the detection range. The integration of f‐HNPC provides enhanced surface area and electrochemical properties, enabling sensitive and selective detection of sweat biomarkers, including glucose (103 µA mM−1 cm−2) and uric acid (184 µA mM−1 cm−2) along with an ultra‐wide glucose detection range (up to 41.5 mM). Moreover, the incorporation of LSG ensures excellent mechanical flexibility, facilitating conformal contact with the skin for reliable signal acquisition. The proposed skin patch demonstrates promising performance in real‐time perspiration analysis and ECG monitoring with a signal‐to‐noise ratio of 23.63 dB, along with high stability and long‐term durability. The synergistic combination of f‐HNPC and LSG shows great potential for developing advanced wearable biosensing platforms for personalized healthcare applications. [ABSTRACT FROM AUTHOR]

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In the late summer of 2015, severe leaf blight occurred on Miscanthus sinensis grown on natural riverside lands of the Han River in Seoul, South Korea. Symptoms included chlorosis and necrotic lesions on the leaves. Gram-negative, non-spore-forming, and rod-shaped Pseudomonas syringae were consistently recovered from the infected leaves. We provide ample evidence for P. syringae pv. syringae ( Pss) as the pathogen, based on the results of LOPAT, Biolog, API tests, MALDI-TOF MS, and multilocus sequence analysis. Symptoms after artificial inoculation were mild compared to symptoms following natural infection, whereas the control plants were asymptomatic. Bacteria re-isolated from leaves with mild symptoms were identical to the original strain, as determined by the rpoD gene sequence. This is the first report of Pss causing bacterial leaf blight on M. sinensis. [ABSTRACT FROM AUTHOR]

The demand for non‐invasive health monitoring with wearables poses challenges in developing sustainable, self‐powered systems, as current energy harvesters face issues like complex fabrication, low robustness, and insufficient power density for continuous biosensing. In this study, a wearable self‐powered biosensing platform combining a electromagnetic‐triboelectric hybrid generator (ETHG) with an advanced electrochemical sweat‐ion‐sensing patch is proposed. A Halbach magnet array within the electromagnetic generator (EMG) enhances magnetic flux concentration and power output, while advanced Nylon@polyallylamine and polyvinylidene fluoride@Co3O4 nanofiber films significantly boost the triboelectric generator's performance. Mechanical and theoretical modeling reveals an optimized power output of 328 mW for the EMG and 0.65 mW for the triboelectric component at 6 Hz. This hybrid approach not only enhances the power density but also simplifies the fabrication process and improves the charging performance and robustness of the system. To address potential drift in solid‐contact ion‐selective electrodes, nanoporous carbon ‐modified electrodes increase hydrophobicity, enhancing sensitivity for Na+ (56.1 mV dec−1), K+ (55.2 mV dec−1), and Ca2+ (30.8 mV dec−1), along with excellent performance in pH (69.7 mV dec−1) sensing. Integrating ETHG with a flexible microfluidics‐enabled patch enables real‐time on‐body sweat monitoring, with data wirelessly transmitted via Bluetooth, offering an efficient and robust platform for continuous health monitoring applications. [ABSTRACT FROM AUTHOR]

Winter squash (Cucurbita maxima) is rich in vitamins C and B6 and is also a source of beta-carotene, a provitamin A carotenoid. About 13,000 tons have been produced annually in South Korea over the past 10 years. In the summer of 2022, severe rot was observed in winter squash for sale at a wholesale market in Jinju, South Korea, with approximately 10% of the 500 squashes observed affected. White fungal hyphae and dark orange spore masses were observed on the surface of the decayed squash. To isolate the causal agents, symptomatic tissues (3 × 3 mm) between diseased and healthy tissues per squash from 3 diseased squashes were excised, disinfested with 1% sodium hypochlorite for 20 s and 70% ethanol for 10 s, washed twice in sterilized distilled water, dried on sterilized filter paper, transferred to water agar, and incubated at 25°C for 2 days. Agar blocks (3 mm 2 ) containing fungal colonies were transferred to potato dextrose agar (PDA) plates and incubated at 25°C until fungal colonies grew. Three isolates (GNU F137a‒c) with similar morphology were subcultured using the single-spore method. In PDA, the colonies looked like gray cotton when viewed from the front, were pale orange from the back, and numerous small black sclerotia-like grains could be observed on both sides. Setae were pale to medium brown, verrucose, 40-120 μm long, and 3-6 septated. Conidiophores were hyaline to pale brown, smooth-walled, septate, branched, and up to 45 μm long. Conidia were hyaline, smooth walled, aseptate, straight, cylindrical, the apex and base rounded, and 14-18 × 5-7 μm (n = 30). Appressoria were single, brown, aseptate, ellipsoidal to irregular in outline, with crenate margins, and 3.5-5 × 3-5 μm (n = 30). The morphological features of the fungal isolates matched descriptions of Colletotrichum species. To confirm the identity of the isolated fungus, genomic DNA of all three isolates was extracted using the Phire Plant Direct PCR Kit (Thermo Fisher Scientific, Baltics, UAB). The internal transcribed spacers (ITS) of the ribosomal RNA gene region, glyceraldehyde-3-phosphate dehydrogenase (GAPDH), chitin synthase 1 (CHS-1), histone H3 (HIS3), actin (ACT), and beta-tubulin (TUB2) genes were amplified and sequenced using the primer pairs ITS1/ITS4, GDF/GDR, CHS-79F/CHS-354R, CYLH3F/CYLH3R, ACT-512F/ACT-783R, and T1/T2, respectively. The sequences were deposited in GenBank (acc. nos., PP504320 and PP555649-PP555653). Concatenated sequences of the six genes obtained from isolates GNU F137a‒c and ex-types from each accepted taxon in previous studies were used to conduct a phylogenetic analysis using the maximum likelihood method in MEGA 11. The fungus isolated from winter squash was in the same clade as C. liaoningense. Therefore, the isolates were identified as C. liaoningense. For pathogenicity tests, three winter squash were wounded with a sterilized needle and inoculated with each isolate by injecting 100 μl conidial suspension (10 5 conidia/ml). Control squash were injected with sterilized distilled water. All treated squash were incubated at 25°C in the dark. The test was performed three times. All inoculated winter squash reproduced symptoms within 15 days, whereas the control squash were symptomless. The morphological characteristics and ITS sequence of the re-isolated strain matched those of the inoculated strain. To the best of our knowledge, this is the first report of fruit rot of winter squash in Korea and is even the first report on C. liaoningense in Korea. This disease is considered a post-harvest disease because no cases have yet been discovered in the field in Korea. This report will facilitate epidemiological research and the development of effective disease control strategies.

Carotenoids are widely used in functional foods, cosmetics, and health supplements, and their importance and scope of use are continuously expanding. Here, we characterized carotenoid biosynthetic genes of the plant-pathogenic bacterium Pantoea ananatis, which carries a carotenoid biosynthetic gene cluster (including crtE, X, Y, I, B, and Z) on a plasmid. Reverse transcription-polymerase chain reaction (RT-PCR) analysis revealed that the crtEXYIB gene cluster is transcribed as a single transcript and crtZ is independently transcribed in the opposite direction. Using splicing by overlap extension with polymerase chain reaction (SOE by PCR) based on asymmetric amplification, we reassembled crtE-B, crtE-B-I, and crtE-B-I-Y. High-performance liquid chromatography confirmed that Escherichia coli expressing the reassembled crtE-B, crtE-B-I, and crtE-B-I-Y operons produced phytoene, lycopene, and β-carotene, respectively. We found that the carotenoids conferred tolerance to UV radiation and toxoflavin. Pantoea ananatis shares rice environments with the toxoflavin producer Burkholderia glumae and is considered to be the first reported example of producing and using carotenoids to withstand toxoflavin. We confirmed that carotenoid production by P. ananatis depends on RpoS, which is positively regulated by Hfq/ArcZ and negatively regulated by ClpP, similar to an important regulatory network of E. coli (Hfq ArcZ →RpoS Ͱ ClpXP). We also demonstrated that Hfq-controlled quorum signaling de-represses EanR to activate RpoS, thereby initiating carotenoid production. Survival genes such as those responsible for the production of carotenoids of the plant-pathogenic P. ananatis must be expressed promptly to overcome stressful environments and compete with other microorganisms. This mechanism is likely maintained by a brake with excellent performance, such as EanR., (© 2020 The Authors. MicrobiologyOpen published by John Wiley & Sons Ltd.)

In June 2019, root mat disease was observed in hydroponically cultivated tomatoes in Jinju, South Korea, which occurred in at least 30% of the plants in the greenhouse. To isolate the causal bacteria, 10 g of infested tomato root mat sample was ground with 50 mL of sterile water. A 100-µL aliquot of the homogenate was serially diluted and spread on Mannitol-Glutamate (MG) medium amended with 0.1% yeast extract (MGY) and incubated at 28°C for 48 hours. Fifteen dominant colonies that formed on the MGY medium were purified and subjected to diagnostic polymerase chain reaction (PCR) based on the virD2-ipt gene loci. Because Ti-plasmid harbors both virD2 and ipt genes, Ri-plasmid-borne Agrobacterium species with only virD2 can be differentiated using virD2-ipt PCR. To amplify virD2, the primers 5'-ATG CCC GAT CGA GCT CAA GT-3' and 5'-TCG TCT GGC TGA CTT TCG TCA TAA-3' were used; for ipt amplification, the primers 5'-GAT CG(G/C) GTC CAA TG(C/T) TGT-3' and 5'-GAT ATC CAT CGA TC(T/C) CTT-3' were used. Amplification involved an initial 94°C for 1 min and then 40 cycles at 94°C, 50°C, and 72°C for 1 min at each temperature, with a final 5-min extension at 72°C. For three strains (GNIY2, J10, and J11), virD2 PCR products, but no ipt PCR products, were identified, indicating that three strains are Ri-plasmid-borne Agrobacterium species. A pathogenicity test was performed on 2-week-old tomato plants. Bacteria isolates (GNIY2, J10, and J11) cultured overnight in LB were made into a bacterial suspension (10 7 cfu/mL) in 50 mM phosphate buffer. Five tomato seedling roots were cut with sterilized scissors and soaked in each bacterial suspension for 1 hour. Phosphate buffer was used as a negative control. The inoculated tomato seedlings were transplanted in new pots and placed in a greenhouse with 25°C day and 20°C night temperature set points in natural light. After 9 weeks, all inoculated tomato plants produced overgrown roots, while the negative control plants had no symptoms. To satisfy Koch's postulates, re-isolation was performed from the diseased tomato and was the re-isolated bacteria were subject to partial 16S rDNA sequencing. Biovar tests performed as previously described revealed that all three isolates were biovar 1. A representative strain (GNIY2) was deposited in the Korean Agricultural Culture Collection (KACC 21759). To confirm the identity, four housekeeping genes of KACC 21759 were sequenced (16S rRNA, trpE, rpoB, and recA) and deposited in GenBank (accession nos. MT071560, MT444428, MT444429, and MT444430). Multilocus sequence analysis performed as previously described showed that the KACC 21759 strain was grouped in Agrobacterium genomospecies 4. This is the first report on mat root disease caused by Agrobacterium biovar 1 in hydroponic tomatoes in South Korea.