Construction of full-length infectious clones of turnip mosaic virus isolates infecting Perilla frutescens and genetic analysis of recently emerged strains in Korea.

Perilla is an annual herb with a unique aroma and taste that has been cultivated in Korea for hundreds of years. It has been widely cultivated in many Asian and European countries as a food and medicinal crop. Recently, several viruses have been reported to cause diseases in perilla in Korea, including turnip mosaic virus (TuMV), which is known as a brassica pathogen due to its significant damage to brassica crops. In this study, we determined the complete genome sequences of two new TuMV isolates originating from perilla in Korea. Full-length infectious cDNA clones of these two isolates were constructed, and their infectivity was tested by agroinfiltration of Nicotiana benthamiana and sap inoculation of Chinese cabbage and radish plants. In addition, we analyzed the phylogenetic relationship of six new Korean TuMV isolates to members of the four major groups. We also used RDP4 software to conduct recombination analysis of recent isolates from Korea, which provided new insight into the evolutionary relationships of Korean isolates of TuMV.

The N-Terminal Region of Cucumber Mosaic Virus 2a Protein Is Involved in the Systemic Infection in Brassica juncea.

Brassica juncea belongs to the Brassicaceae family and is used as both an oilseed and vegetable crop. As only a few studies have reported on the cucumber mosaic virus (CMV) in B. juncea, we conducted this study to provide a basic understanding of the B. juncea and CMV interactions. B. juncea-infecting CMV (CMV-Co6) and non-infecting CMV (CMV-Rs1) were used. To identify the determinants of systemic infection in B. juncea, we first constructed infectious clones of CMV-Co6 and CMV-Rs1 and used them as pseudo-recombinants. RNA2 of CMV was identified as an important determinant in B. juncea because B. juncea were systemically infected with RNA2-containing pseudo-recombinants; CMV-Co6, R/6/R, and R/6/6 were systemically infected B. juncea. Subsequently, the amino acids of the 2a and 2b proteins were compared, and a chimeric clone was constructed. The chimeric virus R/6Rns/R6cp, containing the C-terminal region of the 2a protein of CMV-Rs1, still infects B. juncea. It is the 2a protein that determines the systemic CMV infection in B. juncea, suggesting that conserved 160G and 214A may play a role in systemic CMV infection in B. juncea.

Natural curing agents as nitrite alternatives and their effects on the physicochemical, microbiological properties and sensory evaluation of sausages during storage.

This study investigated the effects of different curing agents on the physicochemical properties, microbiological properties and sensory evaluation of sausages formulated with and without nitrite over 4 weeks of cold storage. Seven batches were prepared: control, sodium nitrite 0.01%; celery powder 0.8% (T1); fruit extract powder 0.6% (T2); purple sweet potato powder 0.45% (T3); fruit and vegetable extract powders 0.5% (T4); gardenia red 0.04% (T5); paprika and blueberry powder 0.07% (T6). T1 produced significantly lighter, redder and yellower sausages compared to control and had a higher color intensity (C*) and hue (h). The residual nitrite ion concentration was the highest in the control and declined most rapidly in control, T1, and T2 during storage. The pH, thiobarbituric acid reactive substances (TBARS), volatile basic nitrogen (VBN) content, and total microbe counts were the same for T1 and the control. T1 received comparable sensory attributes as the control. These results suggest that celery powder effectively protects sausages from quality deterioration during storage.

The Effects of Natural Antioxidants on Protein Oxidation, Lipid Oxidation, Color, and Sensory Attributes of Beef Patties during Cold Storage at 4℃.

This study aimed to investigate the use of golden thread extract (GTE), clove extract (CE), and commercially available nitrite for retarding lipid and protein oxidation and for maintaining color stability and sensory attributes in beef patties stored at 4℃. GTE, CE, and nitrite treatment samples were found to be efficient in retarding lipid oxidation as all three treatments resulted in low thiobarbituric acid reactive substance (TBARS) content (p<0.05). By using GTE, CE, and nitrite into beef patties, protein oxidation was not developed. Incorporation of GTE and CE into beef patties maintained color stability by protecting against the decrease of L*, a*, b*, chroma, and hue angle values and exhibited significant influence on sensory characteristics, including color and odor of beef patties (p<0.05). Compared to commercially available nitrite, GTE and CE were more effective as antioxidants for inhibiting lipid oxidation, and preserving color stability of fresh beef patties. The study indicated that GTE and CE could be utilized efficiently to extend the shelf life of beef patties.

The complete chloroplast genomes of three Korean Echinochloa crus-galli accessions.

The complete chloroplast (cp) genomes of three Echinochloa crus-galli accessions (KR822684, KR822685, and KR822686) are reported in this work. The cp genome size is similar in three accessions, ranging from 139 846 bp to 139 860 bp. All three genomes have two inverted repeats (IR) of 22 748 bp per each IR with a large single copy (LSC) region of 81 833-81 844 bp and a small single copy (SSC) region of 12 517-12 520 bp. The total of 131 genes was identified in individual accession. Phylogenetic analysis revealed three Korean Echinochloa accessions belonged to E. crus-galli, and diverged less than 0.1 million years ago (Mya).