Food Science and Biotechnology
Korean Society of Food Science and Technology (KOSFOST)
- Monthly
- /
- 1226-7708(pISSN)
- /
- 2092-6456(eISSN)
Domain
- Agriculture, Fishery and Food > Science of Food and Crops
- Agriculture, Fishery and Food > Food Science
Aim & Scope
The Food Science and Biotechnology (Food Sci. Biotechnol.; FSB) was launched in 1992 as the Food Biotechnology and changed to the present name in 1998. It is an international peer-reviewed journal published monthly by the Korean Society of Food Science and Technology (KoSFoST). The FSB journal covers; Food chemistry/food component analysis Food microbiology and biotechnology Food processing and engineering Food hygiene and toxicology Biological activity and nutrition in foods Sensory and consumer science s Consumer perception and sensory evaluation on processed foods are accepted only when they are relevant to the laboratory research work. As a general rule, manuscripts dealing with analysis and efficacy of extracts from natural resources prior to the processing or without any related food processing may not be considered within the scope of the journal. The FSB journal does not deal with only local interest and a lack of significant scientific merit. The main scope of our journal is seeking for human health and wellness through constructive works and new findings in food science and biotechnology field.
http://www.fsnb.or.kr/submission/ KSCI KCI SCOPUS SCI SCIEVolume 16 Issue 1
-
Garlic (Allium sativum L.) contains a specific sulfur compound, the S-allyl derivative of L-cysteine sulfoxide, and has long been known for its antimicrobial activity against various microorganisms, including bacteria, fungi, and protozoa. The principal antimicrobial compound of garlic is S-allyl-L-propenethiosulfinate (allicin) which is generated by an enzyme, alliinase (L-cysteine sulfoxide lyase), from S-allyl-L-cysteine sulfoxide (alliin). This compound exists exclusively in Allium as a major non-protein sulfur-containing amino acid. S-Allyl-L-propenethiosulfinate belongs to the chemical group of thiosulfinates and is a highly potent antimicrobial. The potency of garlic extract is reduced during storage since thiosulfinates are unstable and are degraded to other compounds some of which do not have antimicrobial activity. Diallyl polysulfides and ajoene are sulfur compounds derived from allicin that do possess antimicrobial activity. It was recently found that garlic becomes antimicrobial on heating at cooking temperatures, and that the compound responsible for this is allyl alcohol, which is generated from alliin by thermal degradation.
-
The main purpose of flavor research using conventional extraction methods, such as solvent extraction, distillation, and dynamic headspace, is to effectively extract, identify, and quantify flavor volatiles present in food matrices. In recent flavor research, the importance of understanding flavor release during mastication is increasing, because only volatiles available in the headspace contribute to the perception of food 'flavors'. Odor potency differs among flavor volatiles, and the physicochemical characteristics of flavor volatiles affect their release behavior and interaction with various food matrices. In this review, a general overview of flavor release and flavor-food interactions within frozen dessert systems is given with emphasis on chemical, physiological, and perceptual aspects. Chemical and sensory analysis methods competent for investigating such flavor-food interactions are illustrated. Statistical analysis techniques recommended for data acquired from such experiments are also discussed.
-
The objective of this study was to develop and assess the performance of an aseptic system for liquid milk contained in plastic bottles, from a small-scale production standpoint. Commercial sterility tests conducted on the bottled milk were utilized in our assessments of the system, via the identification and monitoring of the principal points of the process. Four 150 L batches of milk with pH values of approximately 6.7 were heat-processed at between 137 and
$143^{\circ}C$ for 10 see in a plate heat exchanger, and then aseptically transferred to 500 mL high-density polyethylene (HOPE) bottles, in an ISO class 7 clean room. The aseptic condition of the bottles was achieved via 10 see of rinsing with a mixture containing 0.5% peracetic acid and 0.8% hydrogen peroxide at$30^{\circ}C$ , followed by another rinse with sterile water. Of the 4 batches processed, 2 were determined to exhibit commercial sterility, on the basis of the physical-chemical and microbiological criteria adopted. It was concluded that some adjustment of the processing line was required in order to achieve full commercial sterility for all processes. The aseptic system developed and assessed in this study was demonstrated to have great potential for the processing and transferring of milk into plastic bottles, from a small-scale production standpoint. -
A linear correlation was found by stepwise multiple regression analysis between the sensory score of barley bran sauce aroma and the absolute gas chromatogram (GC) data transformed with square root. In spite of highly significant relationship between the quantity of the peak and the sensory score, it is difficult to estimate the aroma quality of barley bran sauce samples on the basis of only one peak. Peak 29 (methyl 9,12,15-octadecatrienoate) contributed most to the aroma of barley bran sauce. This was followed by 27 (methyl 9,12-octadecadienoate), 28 (ethyl 9,12-octadecadienoate), 12 (phenyl acetaldehyde), and 9 (methyl furfural) in terms of absolute value. When it was calculated using absolute value transformed by square root, peak 28 (ethyl 9,12-octadecadienoate) made the highest contribution to the aroma of barley bran sauce of among the peaks. It was followed by 31 (9,12-octadecadienoic acid), 27 (methyl 9,12-octadecadienoate), 12 (phenyl acetaldehyde), and 29 (methyl 9,12,15-octadecatrienoate).
-
Lee, Jin-Hwan;Baek, In-Youl;Kang, Nam-Suk;Ko, Jong-Min;Kim, Hyun-Tae;Jung, Chan-Sik;Park, Keum-Yong;Ahn, Young-Sup;Suh, Duck-Yong;Ha, Tae-Joung 29
Five phenolic compounds 1-5 were isolated for the first time from the exudate of geminating peanut (Arachis hypogaea). The structures were fully characterized by analysis of physical and spectral data. All isolated compounds were tested for antioxidant activities using 1,1-diphenyl-2-picrylhydrazyl (DPPH), 2,2-azino-bis-(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS), and hydroxyl radical. Compounds 2, 3, and 5 exhibited a strong scavenging effect on DPPH (2:$IC_{50}\;=\;10.4\;{\um}M$ , 3:$IC_{50}\;=\;45.2\;{\mu}M$ , 5:$IC_{50}\;=\;5.0\;{\mu}M$ ), and ABTS (2:$IC_{50}\;=\;9.6\;{\mu}M$ , 3:$IC_{50}\;=\;5.5\;{\mu}M$ , 5:$IC_{50}\;=\;3.3\;{\mu}M$ ) radical activity, whereas these compounds had weak hydroxyl radical scavenging activity ($IC_{50}\;>\;200\;{\mu}M$ ). The total phenolic contents of the extracts using n-hexane, EtOAc, and n-BuOH were found to be 96.4-964.3 mg gallic acid equivalent per g dry material (GAE/g) and n-BuOH fraction showed the highest total phenolic content (964.3 mg GAE/g). These studies suggest that the exudate of geminating peanut may possess possible health related benefits to humans. -
Junior, Mario Roberto Marostica;Mota, Natasha Onoyama;Baudet, Nathalie;Pastore, Glaucia Maria 37
The biotransformation of monoterpenic agro-industrial wastes (turpentine oil and essential orange oil) was studied. More than 40 fungal strains were isolated from Brazilian tropical fruits and eucalyptus trees and screened for biotransformation of the waste substrates. Solid phase microextraction was used to monitor the presence of volatile compounds in the headspaces of sporulated surface cultures. The selected strains were submitted to submerged liquid culture. The biotransformation of R-(+)-limonene and${\alpha},\;{\beta}-$ pinenes from the oils resulted in${\alpha}-terpineol$ and perillyl alcohol, and verbenol and verbenone, respectively, as the main products. The selected strains were also placed in contact with${\alpha}-$ and${\beta}-$ pinenes standards. It was confirmed that verbenol, verbenone, and${\alpha}-terpineol$ were biotransformation products from the terpenes. A concentration of 90 mg/L of verbenone was achieved by Penicillium sp. 2360 after 3 days of biotransformation. -
Collagen-induced arthritis (CIA) is a model for some types of human autoimmune rheumatoid arthritis (RA). In this study, we examined whether ethanol extract of potato (Solanum tuberosum) is efficacious against CIA in mice. Potato extracts (100 and 200 mg/kg) were orally administered to DBA/1J mice once daily for 49 day after initial immunization with type II collagen. Clinical assessment of disease and measurement of paw edema were conducted throughout the study. The production of CIA-related rheumatoid factor, anti-type II collagen antibody, and cytokines were examined in DBA/1J mice. Serum levels of AST, ALT, creatinine, and lipids were measured, and antioxidant enzyme activity in the spleen was also determined. The arthritis score and paw edema were markedly suppressed in the groups treated with potato extract. Levels of rheumatoid factor, anti-type II collagen antibody, interleukin (IL)-1, IL-6, LDL-cholesterol, and malondialdehyde in sera were also reduced by potato extract treatment. The activities of glutathione peroxidase and glutathione reductase were increased in the spleens of CIA mice treated with potato extract. These findings suggest that potato extract has suppressive effects on type II collagen-induced arthritis, an animal model for human RA.
-
The effects of hydrostatic pressure (HP) treatment on the physicochemical, morphological, and textural properties of bovine semitendinosus (ST) muscle were assessed. Based on SDS-PAGE, the decrease in HP-treated ST muscle protein solubility in 0.1 M KCl buffer (pH 7.0) was attributable to a reduction in the levels of sarcoplasmic protein, and the protein solubility decrease observed in 0.6 M KCl buffer (PH 7.0) was attributable to a reduction in the levels of myosin heavy-chain and actin. Scanning electron microscope (SEM) observations showed that muscle fibers became finer and more compact with increasing pressures. The shear force and hardness of ST muscle pressurized to 300 MPa decreased significantly (p<0.05), however samples pressurized at 100 and 500 MPa exhibited a significant increase in both attributes relative to the control sample (p<0.05).
-
The antioxidant activities of water, ethanol, methanol, and chloroform extracts of Ulmus davidiana were evaluated using various antioxidant assays: DPPH (1,1-diphenyl-2-pricrylhydrazyl) free radical scavenging; hydroxyl radical scavenging; lipid peroxidation scavenging; and reducing power assays. All extracts, except the chloroform extract, demonstrated strong antioxidant activity in all assays. The chloroform extract had the highest hydroxyl radical scavenging activity, and its activity was equivalent to
$\alpha$ -tocopherol at a concentration of 0.5 mg/mL. Additionally, the antidiabetic activity of their extracts was also evaluated using a rat intestinal$\alpha$ -glucosidase inhibition assay. Among all extracts investigated, the methanol extract had the highest$\alpha$ -glucosidase inhibitory activity, although its activity was less than acarbose at$0.5\;{\mu}g/mL$ . This result suggested that U. davidiana extracts may have antidiabetic activity. Total phenolic compounds and flavonoids were also measured. Phenolic compounds such as tannic acid, p-coumatric acid, and kaempferol were detected by high-performance liquid chromatography (HPLC). These results suggest that U. davidiana extracts may be useful as a potential source of antioxidant and antidiabetic materials. -
Four different biopolyester films, two aliphatic polyesters including polylactides (PLA) and poly(3-hydroxy-butyrate-co-3-hydroxyvalerate (PHBV), and two aliphatic-aromatic copolyesters including Ecoplex and Biomax, were prepared using by thermo-compression, and their tensile and water barrier properties were determined. Among the films tested, PLA film was the most transparent (T: 95.8%), strongest, and stiffest (TS, 40.98 MPa; E, 1916 MPa), however it was rather brittle. In contrast, Ecoplex film was translucent while being the most flexible and resilient (EB, 766.8%). Biomax film was semitransparent and was the most brittle film tested (EB, 0.03%). All biopolyester films were water resistant exhibiting very low water solubility (WS) values ranging from 0.0.3 to 0.36%. PHBV film showed the lowest water vapor permeability (WVP) value (
$1.26{\times}10^{-11}\;g{\cdot}m/m^2{\cdot}sec{\cdot}Pa$ ) followed by Biomax, PLA, and Ecoflex films, respectively. The water vapor barrier properties of each film were approximately 100 times higher than those of carbohydrate or protein-based films, but about 100 times lower than those of commodity polyolefin films such as low-density polyethylene (LDPE) or polypropylene (PP). -
Mackerel (Scomber japonicus) often causes severe allergic reactions in sensitive people. Food containing undeclared mackerel may pose a risk to such people. The major allergenic protein in fish such as mackerel, codfish, and Alaska pollack has been found to be parvalbumin. In this study, we developed a polymerase chain reaction (PCR) method to detect mackerel DNA using primers corresponding to the parvalbumin gene. We cloned and sequenced 1.5 kb of parvalbumin gene by PCR using mackerel genomic DNA as a template. Nucleotide sequence analysis of genomic parvalbumin gene, composed of 4 exons and 3 introns, allowed the selection of two pairs of oligonucleotide primers specific for mackerel. These primers successfully enabled PCR amplification of specific regions of genomic parvalbumin DNA from mackerel, but no amplification from 8 other fish samples, surimi, and 6 boiled fish pastes. The sensitivity of this method was sufficient to detect 5 ng of purified mackerel DNA mixed with 50 ng of surimi DNA. This rapid and specific method for the detection of allergenic mackerel would be beneficial in reducing food allergy caused by the ingestion of hidden allergen in processed food.
-
The antioxidant properties of twelve phenolic compounds, including matairesinol 4'-O-
$\beta$ -D-glucoside, 8'-hydroxyarctigenin 4'-O-$\beta$ -D-glucoside, matairesinol, 8'-hydroxyarctigenin, N-feruloylserotonin 5-O-$\beta$ -D-glucoside, N-(p-coumaroyl)-serotonin-5-O-$\beta$ -D-glucoside, N-feruloylserotonin, N-(p-coumaroyl)serotonin, luteolin 7-O-$\beta$ -D-glucoside, luteolin, acacetin 7-O-$\beta$ -glucuronide, and acacetin, isolated from defatted safflower (Carthamus tinctorius L.) seeds were evaluated with regard to the DPPH, superoxide and hydroxyl radicals. Additionally, levels of phenolic compounds were determined by HPLC in two cultivars of safflower seeds. Among them, four serotonin derivatives showed potent DPPH ($IC_{50}=10.83-21.75\;{\mu}M$ ) and hydroxyl ($IC_{50}=75.93-374.63\;{\mu}M$ ) radical scavenging activities, and their activities were significantly stronger than that of${\alpha}-tocopherol$ . Four flavonoids ($IC_{50}=170.65-275.83\;{\mu}M$ ) and four lignans ($IC_{50}=114.22-406.10\;{\mu}M$ ) exhibited significant superoxide and hydroxyl radical scavenging activities, respectively, whereas these compounds contained less activity toward the DPPH and hydroxyl radicals than serotonin derivatives. The levels of serotonin derivatives, lignans and flavonoids in safflower seeds of two cultivars ranged from 49.30 to 260.40, 3.72 to 158.90, and 11.72 to 214.97 mg% (dry base), respectively. Of the two cultivars, 'Cheongsu' had somewthat higher concentrations of phenolic compounds than 'Uisan'. These results suggest that phenolic compounds in safflower seeds may playa role as protective phytochemical antioxidants against reactive oxygen-mediated pathological diseases. -
Park, So-Young;Joo, Seong-Soo;Won, Tae-Joon;Chung, Jin-Woong;Lee, Sung-Hee;Oh, Sun-Woo;Lee, Do-Ik;Hwang, Kwang-Woo 78
Since germanium has been shown to be beneficial for the treatment of diseases such as cancer and rheumatic arthritis, we developed an adapted process of bio-germanium preparation using inorganic germanium. In the present study we determined the optimal conditions for culturing yeast Saccharomyces cerevisiae (KCTC-1199), and the best concentrations of inorganic germanium for the adaptation process. The resulting method was successful at producing high quantities of germanium yeasts. The following are the culture conditions that obtained the highest level of productivity: an inorganic germanium concentration of 3,000-5,000 ppm, a pH of 6.5, a temperature of$35^{\circ}C$ , and 20 hr of incubation time. In addition to this high-yield quantity study, we observed the acute oral toxicity of mice treated with Geranti Bio-Ge$Yeast^{(R)}$ . We found no changes in body weight, or in the mortality between the control groups and the bio-germanium yeast group. There were also no digestive problems such as diarrhea that occurred in either group. -
Kim, Tae-Jin;Sung, Chang-Hyun;Kim, Young-Jin;Jung, Byung-Moon;Kim, Eung-Ryool;Choi, Won-Sun;Jung, Hoo-Kil;Chun, Ho-Nam;Kim, Woo-Jung;Yoo, Sang-Ho 83
In our study, lactic acid bacteria (LAB)-fermented whey solutions were applied in the soybean soaking process to minimize bacterial contamination and to enrich the biologically functional components of isoflavone and$\gamma$ -aminobutyric acid (GABA). Among the 11 LAB tested, Bifidobacteria infantis and a mixed culture (Lactobacillus acidophilus, Bifidobacteria lactis, and Streptococcus thermophilus; ABT-3) displaying the greatest$\beta$ -glucosidase activity were selected to produce improved biologically functional soybean preparations. In the soybean soaking processing (without water spraying), the LAB-cultured 10% whey solution was used to soak and to ferment the soybeans and the fermented soybeans were finally dried by heat-blowing at$55^{\circ}C$ . The processing conditions used in this study demonstrated that the final soybean product had a reduced contamination by aerobic and coliform bacteria, compared to raw soybeans, likely due to the decrease in pH during LAB fermentation. The aglycone content of the isoflavone increased up to 44.6 mg per 100 g of dried soybean by the processing method, or approximately 8-9 times as much as their initial content. The GABA contents in the processed samples increased as the processing time of soaking-fermentation proceeded as well. The soybean sample that fermented by ABT-3 culture for 24 hr showed the greatest increase in GABA content (23.95 to 97.79 mg/100 g), probably as a result of the activity of glutamate decarboxylases (GAD) released from the soybean or produced by LAB during the soaking process. -
The antioxidant activities of water (
$H_2O$ ) and ethanol (EtOH) extracts from hamcho (Salicornia herbacea L.) juice and cake prepared by enzymatic treatments were evaluated by in vitro assays against DPPH, superoxide, and hydroxyl radicals. Among the$H_2O$ and EtOH extracts from five different carbohydrases treated, the EtOH extract from viscozyme-treated hamcho cake had higher yield and phenolic content, and exhibited the strongest radical scavenging activity against DPPH ($IC_{50}=186.91\;{\mu}g/mL$ ), superoxide ($IC_{50}=87.54\;{\mu}g/mL$ ), and hydroxyl radicals ($IC_{50}=367.07\;{\mu}g/mL$ ). Antioxidant assay-guided fractionation and purification of the EtOH extract led to isolation and identification of five phenolic compounds, procatechuic, ferulic and caffeic acids, quercetin, and isorhamnetin. Most of these phenolic compounds exhibited considerable DPPH, superoxide, and hydroxyl radical scavenging activities, and in particular, caffeic and ferulic acids had stronger superoxide and hydroxyl radical scavenging activities than the well-known antioxidant radical scavenger, (+)-catechin (p<0.05). Quercetin and isorhamnetin were the primary compounds responsible for the strong antioxidant activity in the EtOH extract of the viscozyme-treated hamcho cake. Meanwhile, these five phenolic compounds were detected in the EtOH extract of the viscozyme-treated hamcho cake at the following levels (dry base of hamcho); procatechuic acid (1.54 mg%), caffeic acid (6.87 mg%), ferulic acid (8.45 mg%), quercetin (12.63 mg%), and isorhamnetin (6.65 mg%). However, three of these phenolic compounds (procatechuic, caffeic acid, and ferulic acids) were detectable in the$H_2O$ extract of viscozyme-treated hamcho juice. These results suggest that the EtOH extract of viscozyme-treated hamcho cake may be a potential source of natural antioxidants. -
The purpose of this study was to develop a simple detection method, possibly at the species-level, that allows for large-scale screening of bifidobacteria. Human fecal samples were plated on MRS-raffinose agar containing cysteine and neomycin sulfate, serving as selective pressure for bifidobacteria, and 0.003%(w/v) bromocresol green. All of the test strains grew well on this medium at
$37{\pm}1^{\circ}C$ , forming white colonies surrounded by yellow halos, which presented a sharp contrast against the green background. In this disc assay, the required incubation time to develop a yellowish zone varied with the species of Bifidobacterium that was tested, allowing for differential counts and easy identification at the species-level: 10-14 hr for B. bifidum, 20-22 hr for B. catenulatum and B. infantis. and 24-25 hr for B. longum and B. breve. No apparent color was observed for B. angulatum and B. adolescentis 28 hr after inoculation. To evaluate the results of pH indicator-based identification, individual isolates were subjected to a colony-PCR experiment with genus-specific primers. The amplified products from the isolates were in good accordance with those from the reference strains at a level of 95% agreement. These results suggest that the present method could be conveniently applied to cell counts, as well as to the preliminary identification of bifidobacteria from a variety of sample types including human feces, dairy products, and commercial probiotic supplements. -
A multiplex polymerase chain reaction (PCR) method was developed to simultaneously detect three varieties of genetically modified (GM) canola. The construct-specific primers were used to distinguish the following three varieties of GM canola; GT73, MS8xRF3, and T45, using multiplex PCR. The FatA (fatty acyl-ACP thioesterase) gene was used as an endogenous canola reference gene in the PCR detection. The primer pair Canendo-FIR containing a 105 bp amplicon was used to amplify the FatA gene and no amplified product was observed in any of the 15 different plants used as templates. The GT73-KHUF1/R1 primer recognized the 3'-flanking region of GT73, resulting in an amplicon of 125 bp. The Barstar-F1/MS8xRF3-R primer recognized the junction region of bars tar and the NOS terminator introduced into MS8xRF3, resulting in a 162 bp amplicon, and the T45-F2/R2 primer recognized the junction region of PAT and the 35S terminator introduced into T45, resulting in an amplicon of 186 bp. This multiplex PCR allowed for the detection of construct-specific targets in a genomic DNA mixture of up to 1% GM canola containing GT73, MS8xRF3, and T45.
-
In this study we investigated the volatile compounds that are generated in sesame and contribute to its characteristic flavor. Different reaction systems were used to examine how certain amino acids influenced flavor profiles, and also to evaluate the effects of sugar types on the distribution of those volatile compounds. The volatiles that were generated in each reaction system were selectively isolated and analyzed by gas chromatography and gas chromatography-mass spectrometry, respectively. Among the 20 identified compounds, nitrogen-containing alkylpyrazines were found to be the predominant volatiles. The alkylpyrazine amounts varied across the different model systems, with the total yield being highest in the arginine reaction mixture, followed by the alanine, serine, and lysine mixtures. In general, fructose generated the most extensive amount of volatiles compared to glucose and sucrose. However, the yield of specific flavor compounds varied according to the type of sugar used. Finally, the results clearly showed that a reaction temperature of
$135^{\circ}C$ and a reaction time of 20 min generated the highest amount of volatile compounds. -
Wee, Ji-Hyang;Moon, Jae-Hak;Eun, Jong-Bang;Chung, Jin-Ho;Kim, Young-Gook;Park, Keun-Hyung 116
Four compounds with antioxidant activity were isolated from the MeOH extract of peanut shells (pod) and identified as 5,7-dihydroxychromone (1), eriodictyol (2), 3',4',7-trihydroxyflavanone (3), and luteolin (4) by electron impact-mass spectrometry (EI-MS) and nuclear magnetic resonance (NMR) analyses. The relationship between antioxidant activity and chemical structure of the isolated compounds with their analogues [(-)-epicatechin, quercetin, taxifolin] was examined by measuring 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical-scavenging activity and using the 2-deoxy-D-ribose degradation system. The order of antioxidant activity on the basis of DPPH radical-scavenging was quercetin = (-)-epicatechin (6.0 molecules) > taxifolin (4,5 molecules) > 4 (luteolin; 4.0 molecules) > 2 (eriodictyol; 2.5 molecules) > 3 (3',4',7-trihydroxy-flavanone; 2.0 molecules) > 1 (5,7-dihydroxychromone; 0.5 molecules). On the other hand, using the 2-deoxy-D-ribose degradation system, the order of antioxidant activity was quercetin > 4 >> (-)-epicatechin${\geq}\;2\;{\geq}$ taxifolin > 3 > 1. These compounds from peanut shells may provide defensive measures against oxidative stress and insects in the soil. -
The quality of Yukbo strawberry (Fragaria ananassa Duch.) fruit declines rapidly after harvest. Therefore, we examined the effects of nitric oxide (NO) on its respiration rate, quality, and shelf life. Strawberries were fumigated for 5 hr at 0, 50, 100, 200, or
$500\;{\mu}L/L$ NO atmosphers, followed by a hold at$18^{\circ}C$ in air. Treatment with NO delayed the onset of ethylene production ad reduced respiration, which at$18^{\circ}C$ resulted I a maintained quality and prolonged shelf life. The NO-treated strawberries were also firmer and had a lower incidence of disease than the untreated fruit. The effect of NO on fruit quality was dose-dependent. Strawberries that were treated with low and high concentrations of 50 and$500\;{\mu}L/L$ No, respectively, had severe disease incidence and were of poor quality. Treating with NO at a concentration of$200\;{\mu}L/L$ appeared to slow down the ripening and senescence of fruit stored at$18^{\circ}C$ . Calyx browning, respiration, and rot development progressed more quickly in strawberries treated with$500\;{\mu}L/L$ NO compared to those treated with$200\;{\mu}L/L$ No. -
[
${\alpha},\;{\alpha}$ ]-Trehalose was efficiently modified by a transgalactosylation reaction of Escherichia coli${\beta}-galactosidase$ using lactose as a donor to yield two galactosyl trehalose trisaccharides. The reaction products of trehalose by the enzyme were observed by thin layer chromatography (TLC) and high performance anion exchange chromatography (HPAEC) and were purified by BioGel P2 gel permeation chromatography and recycling preparative HPLC. Liquid chromatography-mass spectrometry (LC-MS) and^{13}C$ nuclear magnetic resonance (NMR) analyses revealed that the structures of the main products were$6^2-{\beta}-D-galactosyl$ trehalose (1) and$4^2-{\beta}-D-galactosyl$ trehalose (2). A reaction of 30%(w/v) trehalose and 15%(w/v) lactose at pH 7.5 and$45^{\circ}C$ resulted in a total yield of approximately 27-30% based on the amount of trehalose used. The galactosyl trehalose products were not hydrolyzed by trehalose. In addition the mixture of transfer products (9:1 ratio of 1 to 2) showed higher thermal stability than glucose, lactose, and maltose, but less than trehalose, against heat treatment over$100^{\circ}C$ at pH 4 and 7. It also exhibited better thermal stability than sucrose at pH 4 alone. -
The Strain TFM-7, Which has an antitumor effect, was isolated from Kefir and identified based on analysis using the API 50 CHL kit and 265 rDNA sequencing. Strain TFM-7 was confirmed to belong to the genus Kluyveromyces. Analysis of the 265 rDNA nucleotide sequences found strain TFM-7 to be related to Kluyveromyces marxianus. NRRL Y-828IT. K. marxianus. TFM-7 was cultured with potato dektrose broth medium at
$27^{\circ}C$ for 72 hr, and its inhibition effects on the proliferation of seven tumor cell lines and a normal cell line were assessed using the MTT assay. The antitumor effects and growth characteristics of K. marxianus TFM-7 were investigated during a culture period of 7 days. By the$3^{rd}\;day$ , K. marxianus TFM-7 showed a dry cell weight 2.39 g/L, a pH of 4.39, an ethanol content of 0.89%, and an inhibition effect on the proliferation of seven tumor cell lines above 50%, except for A-549 tumor cell line. K. marxianus TFM-7 was the most effective at inhibiting the growth of Hep-2 cell line among all tumor cell lines tested. Growth inhibition of a normal cell line, NIH/3T3, was less than 35%, suggesting a decreased level of cytotoxicity toward normal cells. These results indicate that K. marxianus TFM-7 may have used as a yeast strain with antitumor activity. -
Byun, Myung-Woo;Lee, Na-Young;Jo, Cheo-Run;Lee, Eun-Young;Kim, Hee-Jeong;Shin, Dong-Hwa 138
The aim of this study was to investigate the effect of irradiation treatment on the inactivation of pathogens in ready-to-use cooked carrot. The pathogens tested were Salmonella typhimurium, Escherichia coli, Staphylococcus aureus, and Listeria inocua. Following the inoculation of these organisms into cooked carrot (about$10^6-10^8\;CFU/g$ ), the growth of each was inhibited due to irradiation for 24 hr of storage at$20^{\circ}C$ . S. typhimurium and E. coli inoculated into cooked carrot were not detected following irradiation with 3 kGy. S. aureus and L. inocua inoculated into the cooked carrot decreased by 5 logs (CFU/g) following 2 kGy irradiation. The range of$D_{10}$ values was from 0.30-0.50. The Hunter color,$L^*-,\;a^*-$ , and$b^*-values$ , and the hardness of the cooked carrot were not effected by irradiation treatment. The sensory score of irradiated cooked carrot was not statistically different from that of non-irradiated samples (p>0.05). These results indicate that low dose irradiation can enhance the microbial safety and extend the shelf-life of ready-to-eat foods such as cooked carrot. -
The levels of citrinin and monacolin K in ten commercial Korean Monascus fermentation products were determined. The products contained citrinin at levels ranging from 0.64 to
$112.27\;{\mu}/kg$ , with only 2 exceeding the limit of$50\;{\mu}g/kg$ set by the Korea Food and Drug Administration (KFDA). The levels of monacolin K ranged from 0.87 to 1,030 mg/kg, however 6 products contained monacolin K at levels lower than 500 mg/kg, the level required by KFDA to be claimed as a functional food. Therefore, many commercial Korean Monascus fermentation products should be considered safe, however many need to be improved before being considered as functional dietary supplements. -
Dynamic rheological properties of hot pepper-soybean paste (HPSP) mixed with xanthan gum were evaluated at different gum concentrations (0.3, 0.6, and 0.9%) and fermentation times (12 and 24 week). Magnitudes of storage (G') and loss moduli (G") in the HPSP-xanthan gum mixture systems increased with an increase in frequency (
$\omega$ ), while complex viscosity (${\eta}^*$ ) decreased. G' values were higher than the G" values over most of the frequency range (0.63-63 rad/sec), and were frequency-dependent. The dynamic moduli (G', G", and${\eta}^*$ ) of the HPSP-xathan mixtures were lower than those of the control (0% gum). The differences between the dynamic moduli values at 12-week and 24-week fermentation decreased with increasing gum concentration, showing that xanthan gum can be used to stabilize and improve the viscoelastic rheological properties of HPSP. The G' value of the HPSP-xathan mixtures increased with an increase in gum concentration from 0.3 to 0.9%, whereas the G" decreased. The ability of xanthan gum to increase the elastic properties in the HPSP-xanthan mixture systems seemed to be the result of the incompatibility phenomena existing between xanthan gum and glutinous rice starch. -
Hydrocarbons have been successfully used as a chemical marker in order to identify irradiated from non-irradiated foods. The method for determining hydrocarbons consists of extraction of fats, followed by separation of hydrocarbons by florisil column chromatography, and then identification of hydrocarbons by GC/MS. Currently, solvent extraction method for fats has certain limitations with regard to extraction time and solvent consumption. Commercial hams and sausage were irradiated at 0 and 5 kGy, and the efficiency of microwave-assisted extraction (MAE) and conventional solvent extraction (CSE) methods on the extraction of radiation-induced hydrocarbons from the meat products was compared. Significant levels of hydrocarbons, mainly composed of 1,7-hexadecadien, 1,7,10-hexadecatriene, and 6,9-heptadecadiene, were detected in the extracts from irradiated hams and sausages by both CSE and MAE methods. Both methods were acceptable in extracting hydrocarbons from samples, but MAE method required apparently reduced amounts of solvent from 150 (CSE) to 50 mL and reduced extraction time from 23 (CSE) to 5 min.
-
Adsorption isotherms for chaga mushroom powder as influenced by particle size were investigated using a gravimetric technique. Samples were equilibrated in desiccators containing sulfuric acid solutions of known water activity (0.11-0.93), then placed in temperature-controlled chambers for approximately ten days. Equilibrium moisture content (EMC) of chaga mushroom powder increased with water activity in all samples. EMC was slightly greater in the samples comprised of smaller particle size, however there was no marked difference in appearance between the three samples. The chaga mushroom powder exhibited Type II behavior. When the BET model was used to determine mean monolayer values, 0.077, 0.077, and 0.070
$H_2O/dry$ solid was observed for <250, 250-425, and$425-850\;{\mu}m$ sized samples, respectively, however mean monolayer values were 0.121, 0.111, and 0.101$H_2O/dry$ solid, respectively, when the GAB model was used. The experimental EMC values were related to the computed values from Henderson's model. The coefficient of determination and standard error for the linear regression were 0.997 and 0.003, respectively. -
Optimization of the fermentation medium for phenylethyl alcohol (PEA) production by Pichia anomala SKM-T was performed. The carbon source (glucose), nitrogen source (L-phenylalanine), and initial pH value were independent variables of the optimized medium. The central composite rotatable design was used for the experimental design and the analysis of the results. The optimum medium composition for the maximal production (621.27 mg/L) of PEA was found to be an initial pH of 5.03, and concentrations of L-phenylalanine at 6.53 and glucose at 6.11 g/L (w/v). This experimental finding is in close agreement with the model prediction (702.79 mg/L; desirability 0.884) with an 11.6% difference.
-
The cytotoxic effects of partially purified substances from Bacillus polylfermenticus SCD toward a variety tumor cell lines were studied. Cytotoxic activity was determined with regard to the A549 (human lung carcinoma), AGS (human stomach adenocarcinoma), DLD-1 (human colon adenocarcinoma), HEC-1-B (human uterus adenocarcinoma), SW-156 (human kidney carcinoma), and NIH/3T3 (murine normal fibroblast) cell lines using the MTT assay. Cytotoxic substances were partially purified through Diaion HP-20 columns and extracted with methanol or other organic solvents (n-hexane, chloroform, ethylacetate, and butanol). B. polyfermenticus SCD supernatant showed up to 60% inhibition of cell viability fer all five human cancer cell lines tested. When treated with 10 mg/mL of n-hexane, chloroform, ethylacetate, and butanol extract, HEC-1-B cells showed a 25,62,35, and 63% rate of inhibition respectively, and AGS cells showed a 72, 61, 44, and 67% rate of inhibition, respectively. At a concentration of 10 mg/mL, 100% methanol Diaion HP-20 extracts showed inhibition rates of 97.0% toward A-549 cells, 98.1% toward AGS cells, 81.6% toward DLD-1 cells, 83.5% toward HEC-1-B cells, and 92.7% toward SW-156 cells. These results indicate that partially purified fractions from B. polyfermenticus SCD have the potential to inhibit not only colon cancer cells, but also lung, stomach uterus, and kidney cancer cells. Further studies are needed to characterize the cytotoxic substances released in B. polyfermenticus SCD cultures.
-
(-)-Epigallocatechin-3-gallate (EGCG), a mai or tea catechin has been shown to have many interesting biological activities. In the present study, we studied the effects of green tea catechins, EGCG metabolites, and black tea theaflavins on accumulation of EGCG in HT-29 human colon cells. Intracellular levels of [
$^3H$ ]-EGCG were not changed significantly in the presence of other tea catechins including (-)-epicatechin, (-)-epigallocatechin, and (-)-epicatechin-3-gallate. EGCG methyl metabolites and EGCG 4"-glucuronide did not affect cellular levels of [$^3H$ ]-EGCG. Black tea theaflavins and theasinensin A (TsA), an EGCG oxidative dimer, however, significantly decreased cellular accumulation of EGCG in HT-29 cells by 31-56%. This decrease was more pronounced when cells were incubated in the presence of theaflavin-3',3"-digallate (TFdiG) or TsA. When EGCG was added separately from TFdiG or TsA, the accumulation of EGCG in HT-29 cells was also significantly decreased regardless of when TFdiG or TsA was added during the uptake study (p<0.01). The results suggest that theaflavins and TsA may interrupt EGCG absorption through the gastrointestinal epithelium.