• Korean Journal of Microbiology
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• v.42 no.3
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• pp.235-237
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• 2006

When fruit bodies of Coprinellus congregatus were matured, they were autolysed to form black ink. During the developmental changes, cell walls of basidia were degraded. Laccase formed melanin which was the typical black pigment of fungi, and chitinase hydrolyzed the chitin which was a component of fungal cell wall. When laccase and chitinase genes were used as the probe for the Northern analysis to confirm their expression during the fruit body development, both gene expressions were increased as the mushroom was getting matured.

• Journal of the Korean Society of Food Science and Nutrition
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• v.41 no.12
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• pp.1677-1685
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• 2012

The autolysate and hydrolysate of a common squid liver, Todarodes pacificus, were prepared. Autolysis (liver ratio, pH, temperature) and Protamex-treated hydrolysis (pH, temperature, ratio of protease to liver) conditions were optimized by response surface methodology using central composite design for under 1 hr of hydrolysis time. The desirability profile indicated that maximum DH could be achieved at a squid liver of 93.5%, pH 6.4, and $47^{\circ}C$ in autolysis, while that of Protamex-treated hydrolysis did at a Protamex-to-squid liver level of 0.33%, pH 6.0, and $55^{\circ}C$. Three amino acids, proline, cysteine, and methionine, were not detected in the total amino acid composition of the Protamex-treated hydrolysate, while they were detected in the free amino acid composition. Cadmium was $8.32{\pm}0.03$ mg/100 g-powder for raw, $3.56{\pm}0.02$ mg/100 g-powder for the autolysate, and $13.26{\pm}0.04$ mg/100 g powder for the Protamex-treated hydrolysate. The major molecular weight ranged from 1.0 to 1.5 kDa for the autolysate and from 210 to 470 Da for the Protamex-treated hydrolysate. Food functionalities of the autolysate, such as surface hydrolphobicity, emulsion activity index, emulsion stability, water, and fat adsorption, were similar to the Protamex-treated hydrolysate. Both the autolysate and Protamex-hydrolysate showed high inhibitory activities on the angiotensin-I converting enzyme. Cell toxicity against the HepG2 cell line was not detected in the autolysate or the Protamex-treated hydrolysate by 200 ${\mu}g/mL$.

• Korean Journal of Food Science and Technology
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• v.31 no.2
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• pp.475-481
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• 1999

Yeast extracts were prepared using either autolysis or enzymatic digestion methods for industrial application of the Saccharomyces cerevisiae B24 strain developed previously to have high RNA content. Extraction ratio of yeast extract from yeast cell reached 65% when autolysis of yeast slurry having 10% solid content was induced at $50^{\circ}C$ and pH 5.0 by agitating with 100 rpm. However, neither 5'-IMP nor 5'-GMP was detected from the autolyzate. In another attempt to prepare a yeast extract S. cerevisiae B24 culture was treated at $90^{\circ}C$ and then treated by various enzymes including ${\beta}-1,3-glucanase$, phosphodiesterase (nuclease P1), adenylic deaminase, and a protease. The yeast extract prepared by the enzymatic digestion method contained 3.2g of 5'-IMP and 5'-GMP/100g dry yeast extract.

• Journal of Nutrition and Health
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• v.41 no.1
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• pp.13-21
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• 2008

To determine whether indol-3-carbinol (BC, $C_9H_9NO$), an autolysis product of a glucosinolate and a glucobrassicin in vegetables, regulated tight junction proteins (TJ) and suppressed cell invasion in colon cancer cells, this experiment was performed. Our results indicate that I3C inhibit cell growth of HT-29 cells in a dose (0, 50, $100{\mu}M$) and time (0, 24 and 48h) dependent manner. Using the wound healing and matrigel invasion study, respectively, BC inhibits the cell motility and invasion of the ovarian cancer cell line. The TEER values were increased in HT-29 cells grown in transwells treated with BC, reversely, paracellular permeability was decreased in those of condition. Claudin-1, claudin-5, ZO-1 and occuldin have been shown to be positively expressed in HT-29 coloncancer cells. I3C occurs concurrently with a significant decrease in the levels of those of proteins in HT-29 cells. But E-cadherin level in the HT-29 was increased by I3C. The reduction of claudin-1 and claudin-5 protein levels occurred post-transcriptionaly since their mRNA levels are no difference by I3C. Therefore, our results suggest that I3C may be expected to inhibit cancer metastasis and invasion by tighten the cell junction and restoring tight junction in colon cancer cell line, HT-29.

• Food Science and Preservation
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• v.8 no.2
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• pp.206-212
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• 2001

Water extract of green tea(GTW) and 70% ethanol extract of green tea(GTE) were prepared for the test of antibacterial activity. The sensitivity of Staphylococcus aureus and Salmonella typhimurium to the green tea extracts in various pH of culture broth was tested. Tryptic soy broth(TSB) containing 0∼2%(w/v) of green tea extracts was adjusted to pH 5.0∼7.0 and inoculated with 10$\^$5/∼10$\^$6/ cells/ml of each bacteria. The plate counting method and clear zone test were used to determine inhibitory effect of green tea extracts. Green tea extracts completely inhibited the growth of S. aureus at 0.5% level and bactercidal at 0.5∼1.0% level of GTW and GTE at pH 5.0∼7.0. Green tea extracts were bactercidal to S. typhimurium at 1.5∼2.0% level of GTW and 1.0∼2.0% level of GTE at pH 7.0. Sal. typhimurium was more resistant than S. aureus. in same concentration of green tea extracts at same pH. The resistance of S. aureus and Sal. typhimurium was increased with decreasing pH of culture broth. The morphology of S. aureus cells treated with green tea extracts showed damage of cell wall and cytoplasmic membrane. Severely damaged cells of S. aureus lost electron dense material and cytoplasm. Green tea extracts stimulated autolysis and cell death of S. aureus. This result suggests that green tea extracts can be used as an effective natural antibacterial agent in food.

• Korean Journal of Food Science and Technology
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• v.25 no.1
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• pp.78-82
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• 1993

This study was carried out to develop a new processing method for the production of yeast autolyzate (YA) by which the yield and the quality could be improved, compared to the conventional method. The result indicated that 85.3% of yeast cell walls treated with glucanase and protease was ruptured by homogenizing at 10,000 psi. Alkali treatment, however, was not effective in disintegrating yeast cell walls. Optimum conditions for autolysis of ruptured yeast cells, obtained with help of response surface methodology (RSM), were pH 7.0, $30^{\circ}C$, ethanol 4% and salt 3%. YA produced by the developed method had significantly higher yield and better sensory quality than that produced by the conventional method.

• Journal of Nutrition and Health
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• v.41 no.3
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• pp.224-231
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• 2008

We examined the effect of indole-3-carbinol (I3C, $C_9H_9NO$), an autolysis product of a glucosinolate and a glucobrassicin in vegetables, on MMP-2, -9 activities and TIMP-l and -2 inductions via microtubule-associated protein kinase (MAPK) signaling pathway in prostate cancer cell line, PC3 cells. Our results indicated that I3C inhibited cell growth of PC3 cells in dose (0,50, 100 ,${\mu}M$) and time (0,24,48 and 72 h) dependent manners. Using gelatin zymography for MMP activity, we demonstrated that I3C significantly decrease MMP-2 and -9 activities in PC3 cells. We also observed that I3C decreased the proteins and mRNA levels of MMP-2 and -9 in PC3 cells as well. Inversely, expressions of TIMP-l and -2 protein and mRNA in PC3 cells were increased by I3C in a dose dependent manner. In another experiment, we showed that I3C inhibited PC3 cells invasiveness by using marigel invasion assay and we also found that I3C suppressed MMP transcriptional activity by MAPK signaling pathways. Taken together, our results suggest that I3C may contribute to the potential beneficial food component to prevent the cancer metastasis in prostate cancer cells. (KoreanJNutr2008; 41(3): 224~23I)

• Korean Journal of Food Science and Technology
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• v.20 no.5
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• pp.650-658
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• 1988

The mobilization of proteins in the cotyledons of germinating soybean seeds (Glycine mar [L.] Merr.) and seedlings was studied by using light microscopy and transmission electron microscopy. The cotyledon tissues of soybean. were packed with protein bodies(diameter $0.1-15{\mu}m$) where storage protein of soybean is deposited. Degradation of protein bodies started in the epidermis and vascular tissues. After swelling of the protein bodies, autolysis of storage proteins began while the external membrane remained unbroken. Hydrolysis of proteins could be internal or peripheral and fusion might begin before complete protein degradation. Possible instances of vacuolar fusion were encountered in some cells. In all cases, the result of degradation was the same; the central vacuole of the cell. At the late stages of seedling growth, breakdown of tonoplast was observed in some cells.

• KSBB Journal
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• v.10 no.5
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• pp.533-539
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• 1995

An autolytic system based on a thermally inducible phage lambda, λHL1, has been applied for the recovery of poly(3-hydroxybutyrate) [PHB] from a recombinant Escherichia coli XL1-Blue, harbouring a plasmid (pSYL105) containing the Alcaligenes eutrophus PHB biosynthesis genes. The lytic capability ofλHL1 was evaluated in flask culture for both lysogens, XL1-Blue (λHL1) and XL1-Blue (λHL1, pSYL105). When the optical density of culture at 600nm(OD600) reached 0.2, cell lysis was induced by increasing the temperature from $30^{\circ}C$ to $42^{\circ}C$. Most cells of XL1-Blue ($\lambda$HL1) were lysed by the autolytic system in an hour after the thermal induction, while the lytic efficiency was slightly lower for XLl-Blue (λHL1, pSYL105). The existence of pSYL105 in cells seemed to inhibit, to some extent, the lytic capability of λHL1 even at low PHB content. The lylic efficiency remarkably decreased as the induction was delayed to allow PHB accumulation. When a chemical induction using 2% (v/v) chloroform was introduced after an hours of thermal induction, we could obtain a good lytic efficiency.

• Korean Journal of Food Science and Technology
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• v.10 no.2
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• pp.136-142
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• 1978

The young cells of Clostridiunm saccaroperbutylacetonicum were rapidly autolysed by exposing them to the hypertonic solution of sucrose(0.3-0.6M) without any other supplement to decompose the rigid cell wall. The cells were converted into the spherical cells by lysis. The spherical cells had following properties: (1) they were absent in the cell wall and osmotically fragile. (2) they were stabilized in the existence of 0.4M sucrose and 5mM $MgSO_4$ (3) they were resistant against adsorption of phage particles. (4) they allowed infection of the isolated phage DNA and produced progeny phage particles. (5) they were able to biosynthesize their macromolecules for a few hours according to a balanced manner of biosynthesis. (6) they were able to produce the bacteriocin particles by mitomycin C treatment. (7) they were unable to multiply. These results were all in the level of typical properties of bacterial protoplasts. It was apparent that the spherical cells formed by lysis occcurring by treatment with hypertonic sucrose were protoplasts.