Effects of Enzyme Treatment on the Physicochemical Properties of Non-glutinous Rice Flour and Effects of Malt Extract Treatment on Retrogradation Extension of Non-glutinous Rice Flour

Kim, Mi-Kyung,Yoon, Ki-Hong,Lee, Gyu-Hee The Korean Society for Applied Biological Chemistr 2010 Applied Biological Chemistry (Appl Biol Chem) Vol.53 No.6

To improve flour quality and extend retrogradation time in processed foods made with non-glutinous rice flour, flour was hydrolyzed using malt extract, which has high amylase activity. The hydrolyzed non-glutinous rice flour (HNGRF) was prepared by response surface methodology (RSM) to optimize the experimental design. The factors for RSM were concentration of malt extract (CME) and enzyme reaction time (ERT). The pasting properties of HNGRF were analyzed using a rapid visco-analyzer (RVA). The optimized conditions were analyzed via setback values in RVA. Enzyme activity of the malt extract used to prepare HNGRF was $34{\pm}1.2$ unit/mL. Setback values, which predict starch retro-gradation, were minimized by treating with 14.22% CME and a 4.21 h ERT. In conclusion, malt extract treatment can improve flour quality and extend retrogradation time in processed foods made with non-glutinous rice flour when optimized conditions of 13-15% CME and 4-5 h ERT are applied.

Addition of thiamine dilaurylsulfate to reduce the intensity of hydrostatic pressure treatment for microbial safety of Korean Jogaejeot-muchim (salted-fermented-seasoned short-neck clam)

Lee, Eun-Jung,Kim, Joo-Sung,Kim, Yun-Ji The Korean Society for Applied Biological Chemistr 2015 Applied Biological Chemistry (Appl Biol Chem) Vol.58 No.6

This study investigated hydrostatic pressure (HP) treatment with the addition of thiamine dilaurylsulfate (TDS) for the microbial safety of the final product (salted-fermented-seasoned short-neck clam) during Jogaejeot-muchim manufacturing process. HP treatment (100-600 MPa) was performed at each step (raw, salted-fermented, and salted-fermented-seasoned short-neck clam) of the Jogaejeot-muchim manufacturing process. The reduction effect on Staphylococcus aureus in the salted-fermented-seasoned short-neck clam step was 1.2 log after 400 MPa treatment, and it was lower than those of raw and salted-fermented short-neck clam steps (4.3 and 4.9 log, respectively) after 400 MPa treatment. To improve the microbial safety of the salted-fermented-seasoned short-neck clam step, TDS (1 g/kg) was added, and 1 log reduction was obtained. In the salted-fermented-seasoned short-neck clam step, HP treatment with TDS addition showed a synergistic effect, and the HP intensity for a 2 log reduction was reduced from 500 to 100 MPa treatment with TDS addition, and a 4 log reduction was achieved by the 300 MPa treatment with addition of TDS. This study concluded that the TDS addition contributed to reducing the intensity of HP treatment required for 99 % inactivation of S. aureus, and that combined treatment (300 MPa treatment with TDS) can be used to provide microbial safety assurance in Korean Jogaejeot-muchim.

Occurrence of Issatchenkia orientalis Exhibiting Inhibitory Effects against Soybean Lipoxygenase in Korean nuruk

Anwar, Yasir,Baek, Seong-Yeol,Yeo, Soo-Hwan,Park, Heui-Dong The Korean Society for Applied Biological Chemistr 2013 Applied Biological Chemistry (Appl Biol Chem) Vol.56 No.2

Three yeast strains (designated SHA, SHC, and SHD) exhibiting strong inhibitory effects against soybean lipoxygenase were isolated from Korean nuruk and identified as Issatchenkia orientalis. Total 80 yeast isolates from two major Korean nuruk samples were analyzed by polymerase chain reaction-restriction fragment length polymorphism and phylogenetic analysis. The most abundant yeast was identified as Pichia anomala, comprising 47 out of 80 strains, followed by 15 strains of I. orientalis. All 15 I. orientalis strains showed significant inhibitory effects against soybean lipoxygenase, higher than that of Saccahromyces boulardii used as a positive control.

Biological Effects of Various Solvent Fractions Derived from Jeju Island Red Sea Cucumber (Stichopus japonicus)

Park, Soo-Yeong,Lim, Hee-Kyoung,Lee, Seog-Jae,Kimcho, So-Mi,Park, Sang-Gyu,Cho, Moon-Jae The Korean Society for Applied Biological Chemistr 2011 Applied Biological Chemistry (Appl Biol Chem) Vol.54 No.5

Red variants of S. japonicus show unique ecological characteristics and are indigenous to Jeju Island in South Korea. Various biological activities of red sea cucumber extracts (RSCEs) were evaluated. In comparison with positive controls, anti-oxidant activity of RSCEs was very low. In HL-60 and HT-29 cells, chloroform and ethyl acetate (EtOAc) fractions showed higher than 80 and 60% growth inhibition, respectively. Nuclear condensation and increased pro-apoptotic signaling revealed that RSCEs triggered apoptosis. EtOAc fractions also showed strong anti-inflammatory effects at sub-lethal concentrations in lipolysaccharide-stimulated RAW264.7 cells and suppressed more than 90% of nitric oxide (NO) and prostaglandin 2 productions at 50 ${\mu}g$/mL by inhibiting inducible NO synthase and cydooxygenase-2. Water-soluble fractions showed good antibacterial effects against Staphylococcus aureus and Staphylococcus epidermidis.

Translocation of chlorpyrifos residue from soil to Korean cabbage

Hwang, Kyu-Won,Moon, Joon-Kwan The Korean Society for Applied Biological Chemistr 2018 Applied Biological Chemistry (Appl Biol Chem) Vol.61 No.2

The loss of residual chlorpyrifos in soil and the amount translocated to Korean cabbage were investigated in this study. Field trials with Korean cabbage were carried out in two greenhouses located in Yongin (Field 1) and Gwangju (Field 2). Soil and Korean cabbage samples were collected on different days following the treatment of soil with chlorpyrifos at two different rates. The initial amounts of residue in soil were 1.15 and 3.58 mg/kg, and these decreased to 0.22 and 0.49 mg/kg at 36 days after treatment (DAT) in Field 1. These values were 20.9 and 59.3 mg/kg, decreasing to 3.03 and 5.24 mg/kg at 43 DAT in Field 2, respectively. In Field 1, the half-life of chlorpyrifos was approximately 15.0 and 10.2 days in soil treated with 0.12 and $0.24g\;a.i./m^2$, respectively. In Field 2, the half-life of chlorpyrifos was approximately 27.7 and 9.6 days following application of 0.36 and $0.72g\;a.i./m^2$, respectively. When compared with the initial concentration in soil, the absorption ratio of chlorpyrifos residue to Korean cabbage was 0.93-6.01 and 0.57-2.61%, respectively. Therefore, safe management guidelines for chlorpyrifos in soil used to cultivate Korean cabbage may be suggested as 3.3 mg/kg regarding the maximum residue limit of chlorpyrifos on Korean cabbage (0.2 mg/kg).

Diversity and community analysis of fermenting bacteria isolated from eight major Korean fermented foods using arbitrary-primed PCR and 16S rRNA gene sequencing

Lee, Se-Hui,Ahn, Min-Ju,Hong, Ji-Sang,Lee, Ju-Hoon The Korean Society for Applied Biological Chemistr 2015 Applied Biological Chemistry (Appl Biol Chem) Vol.58 No.3

Korean fermented foods are known to be beneficial for human health. Bacterial community studies have been conducted to figure out what roles the bacteria used to ferment these foods play in food fermentation. The metagenomic approach identifies both culturable and unculturable bacterial compositions, but this technique is limited in its ability to accurately determine the bacterial species from short 16S rRNA PCR products. In this study, we revisited the culture-dependent method using a relatively large number of bacterial isolates in an attempt to overcome the problem of bacterial identification, accepting that the unculturable bacterial population in each fermented food would be undetectable. Eight Korean fermented foods including kimchi, jeotgal, and meju were collected, and 1589 fermenting bacterial strains were randomly isolated. Bacteria were grouped by banding pattern using arbitrary-primed (AP) PCR prior to bacterial identification and sorted into 219 groups; 351 strains were not grouped because there was no identical AP-PCR band pattern. 16S rRNA sequence analysis identified the bacterial compositions of the fermented foods. As dominant genera, Lactobacillus and Leuconostoc strains were detected in four kimchi samples, Staphylococcus in three jeotgal samples, and Enterococcus and Bacillus in the meju sample. Interestingly, S. Equorum was most dominant in saeu-jeotgal, indicating that it is halophilic and may enhance the fermentation flavor. Further comparative analysis of this study with previous metagenomic results revealed that bacterial communities in fermented foods are highly similar at the genus level but often differ at the species level. This bacterial community study is useful for understanding the roles and functional properties of fermenting bacteria in the fermentation process of Korean fermented foods.

Combined Application of Trichogramma ostriniae and Bacillus thuringiensis for Eco-friendly Control of Plutella xylostella

Hwang, In-Cheon,Park, Chan,Kang, Dong-Kyun,Jin, Na-Young,Jung, Sun-Young,Seo, Mi-Ja,Kim, Jang-Eok,Youn, Young-Nam,Yu, Yong-Man The Korean Society for Applied Biological Chemistr 2010 Applied Biological Chemistry (Appl Biol Chem) Vol.53 No.3

Plutella xylostella (Linnaeus) (Lepidoptera: Plutellidae), is one of the most destructive insect pests of cruciferous crops. This study is to determine the effect of a combined treatment of Bacillus thuringiensis (Berliner) and Trichogramma ostriniae (Peng and Chen) (Hymenoptera: Trichogrammatidae) applied for an eco-friendly control of Diamondback moth, P. xylostella. Results of the investigation of the resistance ratio of four field populations of P. xylostella to B. thuringiensis shows that Hoengseong populations were highly resistance to the 17.1-fold of B. thuringiensis subsp. aizawai and to the 36.0-fold of B. thuringiensis subsp. kurstaki. B. thuringiensis was proven to give no detrimental effects on adult survival and eggs parasitism of the wasp based on contact toxicity test. Survival rates of P. xylostella were 31.67% and 14.17% on single treatment of T. ostriniae and B. thuringiensis, respectively. But, survival rate of P. xylostella was 1.07% on a combined treatment of egg parasitoid and B. thuringiensis. The combined treatment of both biological control agents significantly decreased the crops damage rate, though none of the biological control agents alone showed any significant control efficacy.

Review of Codex Alimentarius and Comparison between the US and Korean Food Classifications for Pesticide Residues of the US and Korea

Im, Moo-Hyeog The Korean Society for Applied Biological Chemistr 2013 Applied Biological Chemistry (Appl Biol Chem) Vol.56 No.6

All countries worldwide are experiencing difficulties in setting maximum residue limits (MRLs) for pesticide residues in food commodities due to prohibitive costs, labor, and other expenses. The Codex Alimentarius (Codex) is actively engaged in revising the classification of food commodities that are grown in small areas; however, setting MRLs for all agricultural commodities has not been effective. Modified food classifications for groups of agricultural commodities were established for setting MRLs of pesticides for each food commodity. Codex accepted various countries' opinions that the old food classification of commodities can no longer be applied to the present food classifications; therefore, from 2009, Codex started to revise their food classifications. To set pesticide MRLs for agricultural products grown in small fields, groups of agricultural commodities were subdivided, and new food classifications were used. The food classification revised by Codex made it easy to set up group MRLs. After the Codex food classification was revised, jujube and persimmon, which were previously classified as tropical fruits, were grouped as pome fruits and stone fruits based on the opinion of the Korea Food & Drug Administration (KFDA). In addition, KFDA submitted more comments on the classification of various vegetables. As a result, Korean vegetables were included in the food classification by Codex. The current Codex food classifications in Korea still have not adopted a group-specific subdivision system that is already used in Codex and the US internationally harmonized food classification revisions by Codex might resolve the difficulty of setting up pesticide MRLs for agricultural commodities such as vegetables in Korea. Consequently, food classifications in Korea, which are in harmony with the Codex food classification, will be of great help in setting the group MRLs for the minor crops of Korea.

Food, cosmetic and biological applications of characterized DOPA-melanin from Vibrio alginolyticus strain BTKKS3

Kurian, Noble K.,Bhat, Sarita G. The Korean Society for Applied Biological Chemistr 2018 Applied Biological Chemistry (Appl Biol Chem) Vol.61 No.2

Melanins are one of the most common pigments produced in nature and distributed throughout the biological kingdom. Vibrio alginolyticus strain BTKKS3 produced DOPA-melanin was used in the study. BTKKS3 melanin inhibited biofilm formation by pathogenic bacteria and effectively decreased the activity of four inflammatory enzymes tested viz. cyclooxygenase, lipoxygenase, myeloperoxidase and nitric oxide synthase. Melanin proved to be less cytotoxic to mouse fibroblast cells with an $IC_{50}$ value of $134.98{\mu}g/mL$. The sun protection factor value of commercial sunscreens was enhanced by 3.42 units by DOPA-melanin.

Roasting Process Enhances Antioxidative Effect of Cinnamon (Cinnamomi Cortex) via Increase in Cinnamaldehyde Content

Yang, Eun-Ju,Kim, Sang-In,Hur, Jong-Moon,Song, Kyung-Sik The Korean Society for Applied Biological Chemistr 2009 Applied Biological Chemistry (Appl Biol Chem) Vol.52 No.5

Regarding chemical and biological activity changes in oriental drugs after food processing such as roasting, fermentation, and extrusion, fifty commonly-used medicinal plants were investigated. As a result, cinnamon (Cinnamomi Cortex) showed remarkably different HPLC profiles and ca 40% of increased antioxidative effect after being roasted. An increased peak was isolated by a reverse phase silica gel chromatography and identified as cinnamaldehyde by means of instrumental analysis including $^1H$ and $^{13}C$ NMR and MS. The enhanced antioxidative effect might originate from the increased content of cinnamaldehyde since this compound is one of the most well known natural antioxidants. The cinnamaldehyde content in cinnamon reached its maximum level after being roasted for 10 min at $120{\pm}2^{\circ}C$ ($108.42{\pm}0.26$ mg/g extract, ca 137 times of increase over untreated control). Although there were no significant changes in in vitro biological activity such as anti-dementia, anti-hypertension or cytotoxicity, before and after the roasting process, the results suggested that simple heat treatment might improve the value of the above oriental drugs since cinnamaldehyde has been shown to possess various biological properties such as antibiotic, antioxidative, anti-diabetic, anti-influenza, and apoptosis-inducing properties.