• 한국식품영양학회지
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• 제10권2호
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• pp.193-200
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• 1997

키토산을 첨가한 저식염 기능성 고추장을 제조하여 숙성 기간별로 이화학적 성분 변화 및 미생물 변화를 조사하였다. 속성 기간 중 회분, 조지방, 조단백질은 젖산 및 키토산의 농도에 따라 별 차이를 보이지 않았으나 수분 함량은 전체적으로 증가하였고, 특히 6% 식염첨가구에서 가장 높은 4.23% 증가를 나타내었다. pH와 적정산도는 키토산 농도에 따라 유의성 있는 변화는 없었다. 알코올 농도는 숙성기간 중 계속 증가하여 4주째에는 0.35~2.19%까지 증가하였으나, 환원당은 숙성 2주까지 증가하여 26.1~27.3%에 이른 후 다시 감소하였고 키토산 농도가 높을수록 알코올 생성과 환원당 감소는 억제하는 것으로 나타났다. 키토산의 첨가가 $\alpha$-amylase의 활성은 약간 저해하였으나, $\beta$-amylase, 산성 protease, 중성 protease의 활성에는 큰 영향을 미치지 않았다. 산성 protease의 경우 9% 식염첨가구에 비하여 6% 식염첨가구 및 6% 식염+젖산, 키토산 첨가구의 효소 활성이 높게 나타났다. 아미노태 질소는 키토산 농도에 관계없이 6% 식염 첨가구들이 9% 식염첨가구에 비하여 전체적으로 높았으며, 암모니아태 질소는 키토산 농도가 높을수록 억제하는 것으로 나타났고, 특히 6% 식염 첨가구의 경우 숙성 4주째에는 170.2mg%까지 증가하였다. 세균수는 숙성 초기 급격히 감소한 후 1주 이후부터는 일정 수준을 유지하였고, 효모수는 숙성 2주까지 증가하다가 감소하는 경향이었다. 키토산 농도가 증가할수록 세균 및 효모의 수도 약간 감소하였다. 이상의 결과에서 키토산 첨가의 최적 농도는 0.25%이었다.

• Asian-Australasian Journal of Animal Sciences
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• 제32권1호
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• pp.72-81
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• 2019

Objective: To determine the effect of gut pH and rumen microbial fermentation on glycerol encapsulated in alginate and alginate-chitosan polymers. Methods: Glycerol was encapsulated at 2.5%, 5%, 7.5%, or 10% (w/w) with sodium alginate (A) and alginate-chitosan (AC) polymers. Surface morphology and chemical modifications of the beads were evaluated using scanning electron microscopy and Fourier transform infrared (FTIR) spectra. Encapsulation efficiency was determined at the 5% glycerol inclusion level in two experiments. In experiment 1, 0.5 g of alginate-glycerol (AG) and alginate-chitosan glycerol (ACG) beads were incubated for 2 h at $39^{\circ}C$ in pH 2 buffer followed by 24 h in pH 8 buffer to simulate gastric and intestinal conditions, respectively. In experiment 2, 0.5 g of AG and ACG beads were incubated in pH 6 buffer at $39^{\circ}C$ for 8 h to simulate rumen conditions. All incubations were replicated four times. Free glycerol content was determined using a spectrophotometer and used to assess loading capacity and encapsulation efficiency. An in vitro experiment with mixed cultures of rumen microbes was conducted to determine effect of encapsulation on microbial fermentation. Data were analyzed according to a complete block design using the MIXED procedure of SAS (SAS Institute, Cary, NC, USA). Results: For AG and ACG, loading capacity and efficiency were 64.7%, 74.7%, 70.3%, and 78.1%, respectively. Based on the FTIR spectra and scanning electron microscopy, ACG treatment demonstrated more intense and stronger ionic bonds. At pH 6, 36.1% and 29.7% of glycerol was released from AG and ACG, respectively. At pH 2 minimal glycerol was released but pH 8 resulted in 95.7% and 93.9% of glycerol released from AG and ACG, respectively. In vitro microbial data show reduced (p<0.05) fermentation of encapsulated glycerol after 24 h of incubation. Conclusion: The AC polymer provided greater protection in acidic pH with a gradual release of intact glycerol when exposed to an alkaline pH.

• 환경위생공학
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• 제20권2호
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• pp.47-55
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• 2005

The World Health Organization(WHO, 1998) and the United States Environmental Protection Agency (USEPA, 1992) recommended $2{\mu}\;guranium/{\ell}$ in drinking water as a guideline. The Korea Institute for Environmental Research recently reported that the radioactive pollution in ground water was almost negligible In Korea$(1999\~2002)$. Cs were cast into beads(2mm in wet form) and treated with hexamethylene diisocyanate for stability in acidic aqueous solution through cross-linking of the beads surfaces. The removal study was carried out in a static batch system and a flow system. In the static system, a certain amount of sample water was confined in a vessel and beads(dry weight 0.5g) were packed into it in order to adsorb uranium for a certain period of time. Afterwards the remaining uranium in water vessel was determined by inductively coupled plasma mass spectrometry. The effective pH range was 4 to 8. The smaller the size of beads, the better the removal efficiency. Furthemore, the lower the flow rates, the higher the removal efficiency. The results showed that chitosan beads can be effectively used for the removal of uranium contained in water.

• 한국의류학회지
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• 제22권8호
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• pp.1011-1019
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• 1998

The natural dyestuff(squid ink) was manufactured from squid ink by boiling in 0.1% NaOH solution and powdering in freeze dryer. Cotton, wool, silk and nylon fabrics were dyed under several conditions using the manufactured squid ink to investigate the dyeability and color fastness. Dyeing was operated in acidic dyebath of pH 4 because the squid ink is anionic. Dyeabilities on wool, silk and nylon fabrics were good, especially silk fabrics were dyed deeper than others because of being amine group. But dyeability on cotton fabrics was low and developed with chitosan treatment. All the dyed fabrics showed excellent in color fastness to crocking and laundering. Also light fastness of them were excellent except nylon. The light fastness of dyed-nylon fabrics was as poor as grade 1, but they could be improved to grade 4 by aftertreatment with gallicacid. Useing the natural dyestuff-squid ink powder, we could execute whenever we want to dye fabrics in the adequate concentration. Dyeabilities were developed according to repeating times of dyeing and the increased dye concentration. We could recycle the wasting sources.

• 대한약학회:학술대회논문집
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• 대한약학회 2003년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2-2
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• pp.229.2-230
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• 2003

Extracellular matrix(ECM) is composed of the ground materials(proteoglycan) and nano size diameter fibrous proteins(ex. collagens) that together form a composite-like structure. In this study, fibrous scaffold with biomimetic architecture based on collagen nanofibers interpenetrated in PLGA/chitosan microfibrous matrix. Chitosan was selected for its structure similarity to glycosaminoglycan and neutralizing capacity for PLGA acidic metabolite. Collagen nanofiber were prepared by electrospinning. (omitted)

• 한국토양비료학회지
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• 제45권5호
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• pp.760-763
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• 2012

친환경 포도재배를 위하여 농가에서 용이하게 구입 및 제조가 가능한 유기농자재의 효과를 조사한 결과 본 연구에 사용한 농자재의 pH는 4.6이하였고, 아미노산액은 상대적으로 높은 비료성분을 함유하였다. 포도수확기 토양의 pH는 시험초기 (농자재 처리 전)와 비교할 때 감소하였고, EC와 유기물함량은 증가하였으며, 유효인산은 대조구 (관행처리)를 제외하고 증가하였다. 치환성 K는 은행잎추출액 처리구와 대조구, 치환성 Ca는 무처리구와 아미노산용액 처리구에서 감소하였고, 치환성 Mg는 모든 농자재 처리구에서 감소하였다. 포도 잎의 질소 (N) 함량은 chitosan과 아미노산액 처리구, P는 chitosan, 목초액 및 아미노산액 처리구, K는 chitosan과 아미노산액 처리구, Ca은 chitosan 처리구, Mg 함량은 아미노산액 처리구에서 가장 높았다. 포도 수량은 목초액 처리구와 대조구에서 $1,581{\sim}1,583kg\;10^{-1}$로 가장 많았고, 당도는 무처리구를 제외하고 같은 수준을 보였다.

• 한국식품영양과학회지
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• 제31권6호
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• pp.977-985
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• 2002

고추장의 품질향상을 위해 다시마와 키토산의 농도를 달리하여 첨가하고 2$0^{\circ}C$에서 24주간 숙성시키면서 효소활성도와 미생물상, 이화학적 튿성을 비교하였다. 고추장의 $\alpha$와$\beta$-amylase는 각각 다시마 2%. 키토산 01.%첨가구에서 조금 높은 활성을 보이나 산성 protease활성은 이들의 첨가농도가 증가하면 감소하였다. 효모수는 숙석 4~8주경에 $10^{5}$~$10^{6}$ CFU/g으로 증가하였고, 세균수는 키토산이나 다시마의 첨가로 감소하였다. 수분은 숙성 12주까지 서서히 증가하나 수분활성도는 감소하였고, 다시마 첨가구에서 낮았다. 점조성은 숙성 중기이후에 증가하였으며 다시마 첨가시 증가되었다. 고추장의 색도는 숙성 중 a값이 낮아졌고, 다시마 첨가량이 증가하면 a와 b값이 낮아졌다. $\Delta$E값은 고추장 숙성중 증가하나 다시마 첨가구에서 낮았다. 적정산도는 4주 이후에 감소되었으며, 키토산의 첨가농도가 높을수록 낮았다. 다시마와 키토산의 농도가 증가할수록 숙성 후기의 아미노태 질소는 많았고, 암모니아태 질소는 키토산 첨가구에서 낮았다. 환원당은 숙성 4~8주에 급격히 증가하였으며, 키토산 첨가량이 증가할수록 많았다. 알콜은 숙성 12~16주까지 증가되었으며, 다시마 첨가구에서 낮았다. 고추장의 맛과 색, 전반적인 기호도는 키토산 01.% 첨가시 좋았고, 다시마는 첨가량이 증가할수록 맛, 색, 향기 모두 낮은 판정을 받았다. 향기 모두 낮은 판정을 받았다.

• The Plant Pathology Journal
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• 제40권3호
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• pp.261-271
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• 2024

Sulfur is one of the inorganic elements used by plants to develop and produce phytoalexin to resist certain diseases. This study reported a method for preparing a material for plant disease resistance. Sulfur nanoparticles (SNPs) stabilized in the chitosan-Cu²⁺ (CS-Cu²⁺) complex were synthesized by hydrolysis of Na₂S₂O₃ in an acidic medium. The obtained SNPs/CS-Cu²⁺ complex consisting of 0.32% S, 4% CS, and 0.7% Cu (w/v), contained SNPs with an average size of ~28 nm as measured by transmission electron microscopy images. The X-ray diffraction pattern of the SNPs/CS-Cu²⁺ complex showed that SNPs had orthorhombic crystal structures. Interaction between SNPs and the CS-Cu²⁺ complex was also investigated by ultraviolet-visible. Results in vitro nematicidal effect of materials against Meloidogyne incognita showed that SNPs/CS-Cu²⁺ complex was more effective in killing second-stage juveniles (J2) nematodes and inhibiting egg hatching than that of CS and CS-Cu²⁺ complex. The values of LC₅₀ in killing J2 nematodes and EC₅₀ in inhibiting egg hatching of SNPs/CS-Cu²⁺ complex were 75 and 51 mg/l, respectively. These values were lower than those of CS and the CS-Cu²⁺ complex. The test results on the nematicidal effect against M. incognita on coffee pots showed that the SNPs/CS-Cu²⁺ complex was 100% effective at a concentration of 150 mg/l. Therefore, the SNPs/CS-Cu²⁺ complex could be considered as a biochemical material with potential for agricultural applications to control root-knot nematodes.

• Macromolecular Research
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• 제17권10호
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• pp.734-738
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• 2009

Biodegradable, pH-sensitive, glycol chitosan (GC) hydrogels were prepared using divinyl adipate (DVA) as a crosslinker and acetic acid as a catalyst. DVA has highly reactive double vinyl ester groups and GC contains a high density of hydroxyl groups, with two in every glucosamine unit. The transesterification reaction between vinyl esters and hydroxyl groups produced crosslinked GC hydrogels. The initial crosslinking reaction was monitored by measuring the viscosity of the reaction mixture. When DVA was added to the GC solution and heated to $50^{\circ}C$, the viscosity of the GC solution gradually increased, implying a crosslinking reaction and hydrogel formation. A new peak from the ester group was observed in the FTIR spectra of the GC hydrogels, confirming the crosslinking reaction. The synthesized GC hydrogel showed pH-dependent water absorbency, mainly due to the presence of amine groups ($-NH_2$) at the C-2 position of the glucosamine unit of GC. The water absorbency greatly increased at acidic pH and slightly decreased at alkaline pH. The GC hydrogel gradually degraded in $37^{\circ}C$ water due to hydrolysis of the ester bonds, which were intermolecular crosslinking sites. A red dye, 5-carboxyltetramethyl-rhodamine (CTMR), was entrapped in the GC hydrogels as a model compound. CTMR was released from GC hydrogels in two steps: an initial burst release mainly due to desorption and diffusion, and a second sustained release possibly due to gradual degradation.

• Journal of Pharmaceutical Investigation
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• 제25권1호
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• pp.19-29
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• 1995

The study was carried out to develop useful formulation for omeprazole(OMP) through OMP-ethylendiamine complex(OMPED), and the pharmaceutical properties of formula were tested to find out the difference in vivo behaviors of formulations between the free and complexed OMP. Oral and suppository dosage forms were also formulated and the dissolution profiles and pharmacokinetic parameters were measured to observe the difference in bioavailability between the free and complex form, and the correlation between dissolution rate and bioavailability was evaluated. The results are summarized as follows; In the case of formulation for oral administration, the release of OMP from enteric OMPED pellets was found satisfactory to the requirement standard and no decomposition of OMP in the pellets was found in acidic solution. Therefore the enteric OMPED pellets are anticipated to be a stable formulation. The release of OMP from OMPED tablet with chitosan as excipient and coated with cellulose acetate phthalate was found to be significantly retarded. The results of bioavailability test for OMP and OMPED tablets with lactose-excipient showed that the AUC value of OMP tablet was $116.89\;{\mu}g\;{\cdot}\;min/ml$, that of OMPED tablet was $161.10\;{\mu}g\;{\cdot}\;min/ml$, respectively. The reason why was thought that OMP decomposes more readily in body than OMPED, and the AUC of the tablet with chitosan-excipient and coated with cellulose acetate phthalate was most enhanced. In the case of bioavailability for suppositories with OMP, $OMP-{\beta}\;-cyclodextrin$ complex and OMPED, the AUC of OMPED suppository was most increased. From the above results, it is thought that the more stable and bioavailable oral or rectal dosage forms could be developed by using the OMPED as a potential OMP complex.