First report on the isolation of immunoglobulin M of guppy, Poecilia reticulata, for the production of polyclonal antibodies     

Siau-Hoi Lim  Hui-Ting Ho  Syed Musthaq S. Khader  Jimmy Kwang   《Aquaculture (Amsterdam, Netherlands)》2009,295(1-2):134-137

As guppies are one of the commercially important fish in freshwater ornamental aquaculture industry, it is important to gain an understanding of guppy immune response for infectious disease control. Till now, the number of study that examined the immune response of guppies is limited and effective tools for monitoring guppy antibody have not been reported. In this study, we successfully isolated guppy IgM using mannan-binding protein (MBP) affinity chromatography and produced specific polyclonal antibodies against guppy IgM heavy and light chains, that showed a molecular weight of approximately 74 and 23 kDa respectively. The produced polyclonal antibodies were used to develop an enzyme-linked immunosorbent assay (ELISA) and have demonstrated to be an effective tool for the detection and quantification of antigen-specific antibody of guppies immunized with Pseudomonas fluorescens. In conclusion, the produced anti-guppy IgM polyclonal antibodies should prove its future implications for immunology and epidemiology studies in guppies.  相似文献   

Pseudoalteromone A,a Ubiquinone Derivative from Marine Pseudoalteromonas spp., Suppresses Melanogenesis     

Su-Jin Lim  Dae-jin Min  Sohee Kim  Jihye Lee  Eun-Soo Lee  Hyuk Kim  Sung-Yoen Cho  Heung-Soo Beak  Chang-Seok Lee  Sang-Jip Nam  Jaeyoung Ko 《Marine drugs》2021,19(11)

An ubiquinone derivative, pseudoalteromone A (1), has been isolated from two marine-derived Pseudoalteromonas spp., APmarine002 and ROA-050, and its anti-melanogenesis activity was investigated. The anti-melanogenic capacity of pseudoalteromone A was demonstrated by assessing the intracellular and extracellular melanin content and cellular tyrosinase activity in the B16 cell line, Melan-a mouse melanocyte cell line, and MNT-1 human malignant melanoma cell line. Treatment with pseudoalteromone A (40 μg/mL) for 72 h reduced α-melanocyte-stimulating hormone (α-MSH)-induced intracellular melanin production by up to 44.68% in B16 cells and 38.24% in MNT-1 cells. Notably, pseudoalteromone A induced a concentration-dependent reduction in cellular tyrosinase activity in B16 cell, and Western blot analyses showed that this inhibitory activity was associated with a significant decrease in protein levels of tyrosinase and tyrosinase-related protein 1 (Tyrp-1), suggesting that pseudoalteromone A exerts its anti-melanogenesis activity through effects on melanogenic genes. We further evaluated the skin-whitening effect of pseudoalteromone A in the three-dimensional (3D) pigmented-epidermis model, MelanoDerm, and visualized the 3D distribution of melanin by two-photon excited fluorescence imaging in this human skin equivalent. Collectively, our findings suggest that pseudoalteromone A inhibits tyrosinase activity and expression and that this accounts for its anti-melanogenic effects in melanocytes.  相似文献   

Viscoelasticity of Cowpea Starch Gels     

So‐Yoon Won  WonSeok Choi  Hyesook S. Lim  Ki‐Yul Cho  Seung‐Taik Lim 《Cereal Chemistry》2000,77(3):309-314

The mechanical behavior of cowpea starch gels (10%, w/v) at small and large deformations were investigated in comparison with acorn, corn, and potato starches in storage at 4°C for seven days. The rapid viscograms of starch paste (7%, w/v) revealed that cowpea starch had a larger setback (1,135 cP) than other starches (465–830 cP), although peak viscosity (1,723 cP) and pasting temperature (76°C) were between those of corn and potato starches. Texture profile analysis of cowpea starch gel showed exceptionally higher values for hardness, gumminess, chewiness and initial modulus than other starch gels. Cowpea starch gel also exhibited higher G′ and smaller tan δ compared with other starch gels, regardless of the storage time. A creep test revealed that the cowpea starch gel could remain highly resistant to stress, showing the least deformation among the tested starch gels during storage up to seven days. The overall results disclosed that cowpea starch was capable of forming exceptionally strong and elastic gels with good storage stability.  相似文献   

Modification of Starch by Dry Heating with Ionic Gums     

S.‐T. Lim  J.‐A. Han  H. S. Lim  J. N. BeMiller 《Cereal Chemistry》2002,79(5):601-606

Waxy maize (native and hydroxypropylated [HP]) and potato starches were impregnated with ionic gums (sodium alginate, CMC, and xanthan, 1% based on starch solids) and heat‐treated in a dry state for 0, 2, or 4 hr at 130°C. Effects of the dry heating on paste viscosity (RVA) and clarity (light transmittance) were examined. Heat treatment with sodium alginate and CMC raised the paste viscosities of native and HP waxy maize starches, but decreased that of potato starch. Xanthan provided the most substantial changes in paste viscosity among the tested gums. It appeared to heavily restrict granule swelling of the waxy maize starches, but it increased swelling of potato starch granules. Dry heating raised the paste viscosity of all the starch‐gum mixtures tested, except the potato starchalginate mixture. The final viscosity at 50°C of a 7% paste was raised in all other starches by ≈500–1,000 cP by this treatment. The paste of waxy maize starch‐gum products became opaque and shorter textured by the heat treatment, regardless of the gum type, whereas potato starch‐gum products did not show any obvious change in paste clarity. Ionic gums could behave as cross‐linking agents as well as form graft copolymers through heatinduced ester formation. This simple heating process with ionic gums could be used as a modification method for starch.  相似文献   

Structural Changes of Debranched Corn Starch by Aqueous Heating and Stirring     

J.‐A. Han  J. N. BeMiller  B. Hamaker  S.‐T. Lim 《Cereal Chemistry》2003,80(3):323-328

Aqueous dispersions (2 mg/mL) of debranched corn starches of different amylose contents (waxy, normal, and high‐amylose) were subjected to extensive autoclaving and boiling‐stirring, and then the changes in starch chain profile were examined using medium‐pressure, aqueous, size‐exclusion column chromatography. As autoclaving time increased from 15 to 60 min, weight‐average chain length (CL_w) of waxy, normal, and high‐amylose corn starches determined using pullulan standards decreased from 46 to 41.2, from 122.1 to 96.3, and from 207.3 to 151.8, respectively. Number‐average chain length (CL_n) measured by the Nelson‐Somogyi method also decreased from 23.0 to 18.4, from 26.4 to 21.8, and from 66.5 to 41.5, respectively, indicating that thermal degradation of starch chains occurred. The CL_w/CL_n ratio for normal corn starch was higher than that for waxy corn starch, indicating an increase in polydispersity of the amylose fraction. Thermal degradation was also observed when the debranched starch was subjected to the boiling‐stirring treatment (0–96 hr). During 96 hr, the CL_w and relative proportion of B≥2 chains of amylopectin released by debranching waxy corn starch increased, whereas those of B1 chains decreased. This change may indicate physical aggregation of B1 chains. But branches from normal and high‐amylose corn starches showed increases in CL_w and the proportion of both B1 and B≥2 chains, along with substantial decreases in those of amylose chains. Therefore, thermal degradation of amylose was greater than that of amylopectin.  相似文献