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In recent years, the rapid development of genetically modified (GM) technology has raised concerns about the safety of GM crops and foods for human health and the ecological environment. Gene flow from GM crops to other crops, especially in the Brassicaceae family, might pose a threat to the environment due to their weediness. Hence, finding reliable, quick, and low-cost methods to detect and monitor the presence of GM crops and crop products is important. In this study, we used visible near-infrared (Vis-NIR) spectroscopy for the effective discrimination of GM and non-GM Brassica napus, B. rapa, and F1 hybrids (B. rapa X GM B. napus). Initially, Vis-NIR spectra were collected from the plants, and the spectra were preprocessed. A combination of different preprocessing methods (four methods) and various modeling approaches (eight methods) was used for effective discrimination. Among the different combinations, the Savitzky-Golay and Support Vector Machine combination was found to be an optimal model in the discrimination of GM, non-GM, and hybrid plants with the highest accuracy rate (100%). The use of a Convolutional Neural Network with Normalization resulted in 98.9%. The same higher accuracy was found in the use of Gradient Boosted Trees and Fast Large Margin approaches. Later, phenolic acid concentration among the different plants was assessed using GC-MS analysis. Partial least squares regression analysis of Vis-NIR spectra and biochemical characteristics showed significant correlations in their respective changes. The results showed that handheld Vis-NIR spectroscopy combined with chemometric analyses could be used for the effective discrimination of GM and non-GM B. napus, B. rapa, and F1 hybrids. Biochemical composition analysis can also be combined with the Vis-NIR spectra for efficient discrimination.

The occurrence of exotic weeds and their influx into farmlands due to climate change poses many problems. Therefore, it is necessary to generate a prediction model for the occurrence pattern of these exotic weeds based on scientific evidence and devise prevention measures. The photosynthetic apparatus is known as the most temperaturesensitive component of a plant cell and its initial response to temperature stress is to inhibit the activation of photosystem II. This study investigated the potential of OJIP transients in assessing temperature stress in exotic weeds. The four exotic weeds currently flowing into Korean farmlands include Amaranthus spinosus, Conyza bonariensis, Crassocephalum crepidioides, and Amaranthus viridis. These weeds were treated at 5°C, 10°C, 15°C, 20°C, 25°C, 30°C, 35°C, and 40°C and the OJIP curves and JIP parameters were measured and analyzed. The results showed that heat and chilling stress affected the photosystem II (PSII) electron transport of A. spinosus, whereas C. crepidioides and A. viridis were more affected by high-temperature stress than by low-temperature stress. Lastly, C. bonariensis showed resistance to both high and low-temperature stress. The results of this study suggest that OJIP transients and JIP parameters can be used to analyze damage to the photosynthetic apparatus by temperature stress and that they can serve as sensitive indicators for the occurrence pattern of exotic weeds.

Near-infrared spectroscopy (NIRS) has become a more popular approach for quantitative and qualitative analysis of feeds, foods and medicine in conjunction with an arsenal of chemometric tools. This was the foundation for the increased importance of NIRS in other fields, like genetics and transgenic monitoring. A considerable number of studies have utilized NIRS for the effective identification and discrimination of plants and foods, especially for the identification of genetically modified crops. Few previous reviews have elaborated on the applications of NIRS in agriculture and food, but there is no comprehensive review that compares the use of NIRS in the detection of genetically modified organisms (GMOs). This is particularly important because, in comparison to previous technologies such as PCR and ELISA, NIRS offers several advantages, such as speed (eliminating time-consuming procedures), non-destructive/non-invasive analysis, and is inexpensive in terms of cost and maintenance. More importantly, this technique has the potential to measure multiple quality components in GMOs with reliable accuracy. In this review, we brief about the fundamentals and versatile applications of NIRS for the effective identification of GMOs in the agricultural and food systems.

Isoflavones are ecophysiologically active secondary metabolites derived from the phenylpropanoid pathway. They were mostly found in leguminous plants, especially in the pea family. Isoflavones play a key role in plant–environment interactions and act as phytoalexins also having an array of health benefits to the humans. According to epidemiological studies, a high intake of isoflavones-rich diets linked to a lower risk of hormone-related cancers, osteoporosis, menopausal symptoms, and cardiovascular diseases. These characteristics lead to the significant advancement in the studies on genetic and metabolic engineering of isoflavones in plants. As a result, a number of structural and regulatory genes involved in isoflavone biosynthesis in plants have been identified and characterized. Subsequently, they were engineered in various crop plants for the increased production of isoflavones. Furthermore, with the advent of high-throughput technologies, the regulation of isoflavone biosynthesis gains attention to increase or decrease the level of isoflavones in the crop plants. In the review, we begin with the role of isoflavones in plants, environment, and its benefits in human health. Besides, the main theme is to discuss the updated research progress in metabolic engineering of isoflavones in other plants species and regulation of production of isoflavones in soybeans.

Bacterial communities in rhizosphere and root nodules have significant contributions to the growth and productivity of the soybean (Glycine max (L.) Merr.). In this report, we analyzed the physiological properties and dynamics of bacterial community structure in rhizosphere and root nodules at different growth stages using BioLog EcoPlate and high-throughput sequencing technology, respectively. The BioLog assay found that the metabolic capability of rhizosphere is in increasing trend in the growth of soybeans as compared to the bulk soil. As a result of the Illumina sequencing analysis, the microbial community structure of rhizosphere and root nodules was found to be influenced by the variety and growth stage of the soybean. At the phylum level, Actinobacteria were the most abundant in rhizosphere at all growth stages, followed by Alphaproteobacteria and Acidobacteria, and the phylum Bacteroidetes showed the greatest change. But, in the root nodules Alphaproteobacteria were dominant. The results of the OTU analysis exhibited the dominance of Bradyrhizobium during the entire stage of growth, but the ratio of non-rhizobial bacteria showed an increasing trend as the soybean growth progressed. These findings revealed that bacterial community in the rhizosphere and root nodules changed according to both the variety and growth stages of soybean in the field.

Background: Tacrolimus (TAC) is a main therapy for liver transplantation (LT) patients, but it has side effects such as chronic nephrotoxicity that progressively aggravate renal function. The purpose of this study was to retrospectively compare the renal function be tween a TAC group and a combination of everolimus and reduced TAC (EVR-TAC) group after deceased donor liver transplantation (DDLT). Methods: The study comprised 131 patients who underwent DDLT between January 2013 and April 2018 at our institution. They received TAC or EVR-TAC after DDLT. Everoli mus (EVR) was introduced between 1 and 6 months after DDLT. Results: Thirty-six of 131 patients (27.5%) received EVR-TAC. The incidence of chronic kidney disease (CKD; estimated glomerular filtration rate

Two kinds of anticaking agents (dextrin, polydextrose) were combined with kiwifruit paste at 5% w/w ratio and freeze-dried to prepare a powdered material. The physiochemical characteristics of kiwifruit powders with anticaking agents were compared with those without anticaking agents as the control. The yield was higher in the powders with anticaking agents than the control. Moisture content, acidity, and total phenolics were lower in the powders with anticaking agents than the control. The contents of vitamin C was higher in the powders with anticaking agents than the control, but was no significant difference with different anticaking agent types. There were no significant differences in free sugar content (fructose, glucose, total sugar) and organic acid content (oxalic acid, lactic acid, total) depending on the anticaking agent types. Hunter’s L-value was significantly high in the order of the samples with dextrin, the control, and polydextrose, while a-value showed an opposite tendency. Browning index, water solubility, and swelling power didn't show any significant difference. However, the hygroscopicities with elapsed time were lower in the powders with anticaking agents than the control. Therefore, the kiwifruit powder combined with dextrin or polydextrose as an anticaking agent at 5% w/w ratio could be used as a food biomaterial with a good quality in moisture, vitamim C, color value, browning index, water solubility, and hygroscopicity.

Nematicidal and hatching inhibition activities (HIA) of the methanol extracts from Dryobalanops aromatica (DA) and Mentha haplocalyx var. piperascens (MH), their constituents, and emulsified concentrate and granule formulations containing the methanol extracts as active ingredients, were compared with those of commercial nematicides, cadusafos and fosthiazate, against Meloidogyne incognita second-stage juveniles (J2) and eggs using well plate, container and pot assays. In a well plate assay with J2, DA applied at 500, 250 and 125 ppm resulted in 100, 95 and 55% mortality, respectively, while MH showed 80% mortality even at the lower concentration of 63 ppm. MH gave stronger HIA than DA at 1000 and 500 ppm. In addition, α-pinene, camphor, borneol and p-menthole, which are the main components of DA and MH extracts, showed strong nematicidal properties and HIA. In particular, the nematicidal activity of p-menthole among them was the highest and its HIA was also stronger than that of cadusafos and fosthiazate. In a container test using emulsifiable concentrate (EC) and granule (G) formulations containing 50 and 30% DA and MH, respectively, EC of D. aromatica showed a stronger LC50 value (0.203 μl (g soil)−1) than G formulation (0.935 mg (g soil)−1). However, their effects were fewer than MH formulations. The lethality of EC and G formulations containing MH was comparable to that of fosthiazate soluble concentrate and granule formulations. In another test using pots containing soils naturally infected by M. incognita, these plant formulations significantly inhibited the nematode-population density judging from the number of galls that formed on tested tomato roots after 8 weeks. These results suggest that DA and MH methanol extracts, as well as their constituents, might be useful as management agents against M. incognita.

To produce genistein in rice, the isoflavone synthase (IFS) genes, SpdIFS1 and SpdIFS2 were cloned from the Korean soybean cultivar, Sinpaldalkong II as it has a higher genistein content than other soybean varieties. SpdIFS1 and SpdIFS2 show a 99.6% and 98.2% identity at the nucleotide level and 99.4% and 97.9% identity at the amino acid level, respectively, with IFS1 and IFS2 from soybean (GenBank accession Nos. AF195798 and AF195819). Plant expression vectors were constructed harboring SpdIFS1 or SpdIFS2 under the control of a rice globulin promoter that directs seed specific expression, and used to transform two rice varieties, Heugnam, a black rice, and Nakdong, a normal rice cultivar without anthocyanin pigment. Because naringenin, the substrate of SpdIFS1 and SpdIFS2, is on the anthocyanin biosynthesis pathway, the relative production rate of genistein was compared between SpdIFS-expressing transgenic Heugnam and Nakdong. Southern blot analysis of eight of the resulting transgenic rice plants revealed that the T0 plants had one to three copies of the SpdIFS1 or SpdIFS2 gene. The highest level of genistein content found in rice seeds was 103 μg/g. These levels were about 30-fold higher in our transgenic rice lines than the genistein aglycon content of a non-leguminous IFS-expressing transgenic tobacco petal, equaling about 12% of total genistein content of Sinpaldalkong II. There were no significant differences found between the genistein content in Heugnam and Nakdong transgenic rice plants.

The effect of two surfaces (amorphous silica and silica sand) on the reduction of chromium(VI) by zero-valent iron (Fe(0)) was investigated using batch reactors. The amendment of both surfaces significantly increased the rate and extent of Cr(VI) removal. The rate enhancement by amended surfaces is presumed to result from scavenging of Fe(0)-Cr(VI) reaction products by the provided surfaces, which minimized surface deactivation of Fe(0). The rate enhancing effect was greater for silica compared to sand, and the difference is attributed to silica's higher surface area, greater affinity for reaction products and pH buffering effect. For a given mass of Fe(0), the reactivity and longevity of Fe(0) to treat Cr(VI) increased with increasing dose of silica. Elemental analyses of the reacted iron and silica revealed that chromium removed from the solution was associated with both surfaces, with its mass distribution being approximately 1:1 per mass of iron and silica. The overall result suggests reductive precipitation was a predominant Cr(VI) removal pathway, which involves initial reduction of Cr(VI) to Cr(III), followed by formation of Cr(III)/Fe(III) hydroxides precipitates.