• Journal of Microbiology and Biotechnology
• /
• v.16 no.12
• /
• pp.1904-1911
• /
• 2006

The cell-free extracts of 250 yeasts were screened for their in vitro anti-angiogenic activity, to develop a new cancer metastasis inhibitor. Saccharomyces cerevisiae K-7 was selected as the producer of the anti-angiogenic agent, because it had the highest anti-angiogenic activity. The anti-angiogenic agent was produced maximally from hydrolysates of Saccharomyces cerevisiae K-7, when the yeast was cultured in yeast extract-peptone-dextrose medium at 30$^{\circ}C$ for 24 h, and cell-free extracts were than digested with pepsin for 4 h at 37$^{\circ}C$. The anti-angiogenic agent was further purified by ultrafiltration, Sephadex G-25 gel permeation chromatography and reverse-phase HPLC, and the anti-angiogenic activity of the final purified preparation was 72.7% at 10 $\mu$M/egg. The purified anti-angiogenic agent was found to originate from the glyceraldehyde-3-phosphate dehydrogenase (GAPDH) molecule of Saccharomyces cerevisiae K-7, and its peptide sequence was Val-Ser-Trp-Tyr-Asp-Asn-Glu-Tyr-Gly-Tyr-Ser-Thr-Arg-Val-Val-Asp. In the MTT assay, the shape of the HT-l 080 cell was clearly changed to a circular type at 0.2 mM purified anti-angiogenic agent. This result indicated that the growth of the HT-I080 cell was significantly inhibited at 0.2 mM of the purified anti-angiogenic agent. The MMP activity of the treated HT-l080 cells was not affected, evidenced by the gelatin zymography, indicating that the anti-angiogenic mechanism of the purified anti-angiogenic agent is not mediated through MMP activity.

• Journal of Microbiology and Biotechnology
• /
• v.29 no.12
• /
• pp.1894-1903
• /
• 2019

The purpose of this study was to determine the probiotic properties of Lactobacillus brevis KCCM 12203P isolated from the Korean traditional food kimchi and to evaluate the antioxidative activity and immune-stimulating potential of its heat-killed cells to improve their bio-functional activities. Lactobacillus rhamnosus GG, which is a representative commercial probiotic, was used as a comparative sample. Regarding probiotic properties, L. brevis KCCM 12203P was resistant to 0.3% pepsin with a pH of 2.5 for 3 h and 0.3% oxgall solution for 24 h, having approximately a 99% survival rate. It also showed strong adhesion activity (6.84%) onto HT-29 cells and did not produce β-glucuronidase but produced high quantities of leucine arylamidase, valine arylamidase, β-galactosidase, and N-acetyl-β-glucosaminidase. For antioxidant activity, it appeared that viable cells had higher radical scavenging activity in the 2,2-diphenyl-1-picryl-hydrazyl (DPPH) assay, while in the 2-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid (ABTS) assay, heat-killed cells had higher antioxidant activity. Additionally, L. brevis KCCM 12203P showed higher lipid oxidation inhibition ability than L. rhamnosus GG; however, there was no significant difference (p < 0.05) between heat-killed cells and control cells. Furthermore, heat-killed L. brevis KCCM 12203P activated RAW 264.7 macrophage cells without cytotoxicity at a concentration lower than 10⁸ CFU/ml and promoted higher gene expression levels of inducible nitric oxide synthase, interleukin-1β, and interleukin-6 than L. rhamnosus GG. These results suggest that novel L. brevis KCCM 12203P could be used as a probiotic or applied to functional food processing and pharmaceutical fields for immunocompromised people.

• The Journal of Korean Medicine
• /
• v.27 no.2 s.66
• /
• pp.103-110
• /
• 2006

Objectives : This study was conducted to investigate the effects of ginseng saponins and commercial surfactants such as Triton X-100, sodium deoxycholate, and sodium dodecyl sulfate on the gastric enzyme-catalyzed hydrolysis. Methods : Saponins (a surface-active plant component) from fresh ginseng root were extracted to examine its effect on the gastric enzyme-catalyzed hydrolysis. Commercial surfactants such as Triton X-100, sodium deoxycholate, and sodium dodecyl sulfate were also employed in the hydrolysis system to compare their effects with that of the ginseng saponins. The effects of surfactants on the gastric enzyme-catalyzed hydrolysis were measured by using a spectrophotometer. A spectropolarimeter was used to examine the conformational change of enzymes and substrates by the addition of ginseng saponins into the system. Results : Both the tryptic and the peptic digestion of milk casein or eggalbumin were slightly improved with an increase in the amount of ginseng saponins in the system. Triton X-100 showed an effect similar to that of ginseng saponins, while sodium dodecyl sulfate and sodium deoxycholate diminished the hydrolysis. Circular dichroism spectra of enzymes and substrates was significantly changed by the addition of ginseng saponins into the system. Conclusions : These results show that ginseng saponins affect positively the gastric enzyme-catalyzed hydrolysis, and suggest that the digestion of substrates by gastric enzymes is affected by the change of enzyme conformation by ginseng saponins.

• Asian-Australasian Journal of Animal Sciences
• /
• v.21 no.10
• /
• pp.1522-1528
• /
• 2008

The objective of this study was to develop a model for simulating gastric digestion in the pig. The model was constructed to include the chemical and physical changes associated with gastric digestion such as enzyme release, digestion product removal and gastric emptying. Digesta was collected from the stomach cannula of pigs to establish system parameters and to document the ability of the model to simulate gastric digestion. The results showed that the average pH of gastric digesta increased significantly from 2.47 to 4.97 after feed consumption and then decreased 140 min postprandial. The model described the decrease in pH within the pigs' stomach as $pH_t=5.182e^{-0.0014t}$, where t represents the postprandial time in minutes. The cumulative distribution function of liquid digesta was $V_t=64.509e^{0.0109t}$. The average pepsin activity in the liquid digesta was 317Anson units/mL. There was significant gastric emptying 220 min after feed consumption. The cybernetic dynamic system of gastric digestion was set according to the above data in order to compare with in vivo changes. The time course of crude protein digestion predicted by the model was highly correlated with observed in vivo digestion (r = 0.97; p = 0.0001), Model prediction for protein digestion was higher than that observed for a traditional static in vitro method (r = 0.89; p = 0.0001).

• Microbiology and Biotechnology Letters
• /
• v.41 no.2
• /
• pp.249-252
• /
• 2013

The Bacillus KU801 strain, due to its potential in the field of probiotics for animal use, was isolated from chicken feces. Strain KU801 was identified as Bacillus amyloliquefaciens KU801 based on the results of 16S rRNA sequencing. Vegetative and spore cells of B. amyloliquefaciens KU801 were resistant to artificial gastric juice and artificial bile acid. B. amyloliquefaciens KU801 was found to inhibit the production of nitric oxide (NO) and increase the production of Interleukin-1 alpha (IL-1${\alpha}$). DNA damage induced by N-methyl-Ntion of ninitroso-guanidine (MNNG) was significantly inhibited, in a dose dependent manner, by preincubating MNNG together with B. amyloliquefaciens KU801. These results demonstrate the potential use of B. amyloliquefaciens KU801 as a feed additive.

• Journal of Pharmaceutical Investigation
• /
• v.23 no.3
• /
• pp.145-153
• /
• 1993

Retaining a drug in the stomach by some means is sometimes necessary to extend the G1 absorption time of the drug more than 6-8 hrs. Hydrogel has often been examined for its feasibility as a dosage form, so called platform, that could be retained in the stomach due to its excellent swelling properties in the gastric fluid. In this study, polyvinylpyrrolidone (PVP) hydrogel crosslinked by albumin or acrylated albumin was synthesized in a tablet form and evaluated for its possibility as the platform. The synthesis of the hydrogel was performed by $^{60}Co\;{\gamma}-ray$ irradiation of N-vinyl-2-pyrrolidone (monomer) in the presence of a crosslinking agent: aqueous solution of albumin or acrylated albumin. Synthetic conditions such as radiation dose, dose rate and concentration of crosslinking agent were varied in order to optimize the swelling and mechanical properties of the hydrogels. Degree of swelling of albumin-crosslinked PVP (Al-PVP) was highly dependent on radiation dose, dose rate and albumin concentration: it was decreased as they increased. On the other hand, that of acrylated albumin-crosslinked PVP (Acryl-PVP) was almost independent on them except dose rate: it was decreased as the radiation dose rate increased. The compressive strength of the two hydrogels was decreased as the dose rate increased. Digestion of both PVP in artificial gastric fluid containing pepsin was delayed by the ${\gamma}-ray$ irradiation. In conclusion, Al-PVP and Acry-PVP with diverse swelling and mechanical properties could be obtained by controlling synthetic conditions, mainly the irradiation dose rate.

• Fisheries and Aquatic Sciences
• /
• v.15 no.2
• /
• pp.137-143
• /
• 2012

The abalone Haliotis discus hannai, is one of the economically important species in the fisheries industry. Abalone intestines are one of the by-products of its processing. To investigate its bioactive potential, abalone intestine was digested using an in vitro gastrointestinal (GI) digestion system containing pepsin, trypsin, and ${\alpha}$-chymotrypsin. The abalone intestine G1 digests (AIGIDs) produced by the GI digestion system were fractionated into AIGID I (> 100 kDa), AIGID II (10-100 kDa), and AIGID III (1-10 kDa) using an ultrafiltration membrane system. Of the three digests, AIGID II and AIGID III exhibited inhibitory effects against matrix metalloproteinase-2 and -9 (MMP-2, MMP-9) in HT1080 human fibrosarcoma cells. Both fractions potently inhibited gelatine digestion by MMP-2 and MMP-9 treated with phorbol 12-myristate 13-acetate (PMA) and migration of HT1080 cells in dose dependently. Furthermore, AIGID II and III attenuated expression of p65, a component of nuclear transcription factor kappa B. These results indicate that of the abalone intestine digests inhibit MMP-2 and MMP-9. Thus, the AIGIDs or their active components may have preventive and therapeutic potential for diseases associated with MMP-2 and MMP-9 activation in fibrosarcoma cells.

• Journal of Microbiology and Biotechnology
• /
• v.26 no.3
• /
• pp.461-468
• /
• 2016

In recent years, various naturally occurring defence peptides such as plectasin have attracted considerable research interest because they could serve as alternatives to antibiotics. However, the production of plectasin from natural microorganisms is still not commercially feasible because of its low expression levels and weak stability. A tandemly arrayed plectasin gene (1,002 bp) from Pseudoplectania nigrella was generated using the isoschizomer construction method, and was inserted into the pPICZαA vector and expressed in Pichia pastoris. The selected P. pastoris strain yielded 143 μg/ml recombinant plectasin (Ple) under the control of the methanol-inducible alcohol oxidase 1 (AOX1) promoter. Ple was estimated by SDS-PAGE to be 41 kDa. In vitro studies have shown that Ple efficiently inhibited the growth of several gram-positive bacteria such as Streptococcus suis and Staphylococcus aureus. S. suis is the most sensitive bacterial species to Ple, with a minimum inhibitory concentration (MIC) of 4 μg/ml. Importantly, Ple exhibited resistance to pepsin but it was quite sensitive to trypsin and maintained antimicrobial activity over a wide pH range (pH 2.0 to 10.0). P. pastoris offers an attractive system for the cost-effective production of Ple. The antimicrobial activity of Ple suggested that it could be a potential alternative to antibiotics against S. suis and S. aureus infections.

• THE JOURNAL OF KOREAN ORIENTAL ONCOLOGY
• /
• v.4 no.1
• /
• pp.1-16
• /
• 1998

In order to investigate the effect of Bujaleejungtang, by means of oral medication to rats and mice, to isolated intestine and stomach, and the effect to pyloric ulcer, indomethacin-induced ulcer, secretion of gastric juice, and to transport ability of intestine content were studied as the action to G-I tract. The effect to normal rats and resperpine-treated rats were studied as the action to thermo-regulation. The results were as follows: 1. Bujaleejungtang showed the inhibitory effect on the smooth muscle contraction induced by acethylcholine chloride and barium chloride in the isolated mice ileum. 2. Bujaleejungtang showed inhibitory effect on the contraction induced by acetylcholine chloride and barium chloride in the rat fundus-strip. 3. Inhibitory effect of Bujaleejungtang on pyloric ulcer, indomethacin-induced gastric ulcer in rats was statistical recognized(p<0.05). 4. No inhibitory effect of Bujaleejungtang on gastric juice secretion in Shay rats was recognized. 5. Inhibitory effect of Bujaleejungtang on gastric free acidity and total acidity in Shay rats was recognized only when Bujaleejungtang was medicated in high thickness(2000mg/kg) (p<0.001). 6. Inhibitory effect of Bujaleejungtang on pepsin output in Shay rats was recognized only when Bujaleejungtang was medicated in high thickness(2000mg/kg)(p<0.001). 7. Inhibitory effect of Bujaleejungtang on barium sulfate transport in the small intestine of mice was recognized only when Bujaleejungtang was medicated in high thickness(2000mg/kg)(p<0.05). 8. Inhibitory effect of Bujaleejungtang on barium sulfate transport in the large intestine of mice was recognized(p<0.05). 9. Inhibitory effect of Bujaleejungtang on rectal temperature in normal rats was recognized. 10. Inhibitory effect of Bujaleejungtang on rectal temperature in reserpine-treated rats was recognized only when Bujaleejungtang was medicated in high thickness(2000mg/kg)(p<0.05).

• Polymer(Korea)
• /
• v.37 no.3
• /
• pp.262-268
• /
• 2013

pH-sensitive P(MAA-co-PEGMA) hydrogel particles were prepared and their feasibility as smart delivery carriers for cosmetic ingredients was evaluated. P(MAA-co-PEGMA) hydrogel particles having an average size of approx. $2{\mu}m$ were synthesized via dispersion photopolymerization. There was a drastic change in the swelling ratio of P(MAA-co-PEGMA) particles at a pH of around 5 due to the ionization of MAA in the hydrogel and as the amount of MAA in the hydrogel increased, the swelling ratio increased at a pH above 5. The P(MAA-co-PEGMA) hydrogel particles showed a pH-sensitive release behavior. Thus, at pH 4 almost none of the albumin permeated through the skin while at pH 6 relatively high skin permeability was obtained. The albumin loaded in the P(MAA-co-PEGMA) hydrogel particles was hardly degraded in the presence of pepsin and its stability was maintained.