• 제목/요약/키워드: Bioassays

Search Result 174, Processing Time 0.036 seconds

Potential Feeding Value of Deoiled Rice Bran by Japanese Quails. 1. The Metabolisable Energy Content

  • Bhanja, S.K.;Verma, S.V.S.
    • Asian-Australasian Journal of Animal Sciences
    • /
    • v.14 no.5
    • /
    • pp.680-683
    • /
    • 2001
  • The apparent metabolisable energy (AME) and N-corrected ME (AMEn) of deoiled rice bran (DORB) were determined with adult quails at 6 and 10- week of age. The DORB obtained from two types of extraction process, Batch (DORB-B) and the Continuous (DORB-C), was each included in a practical type of the reference diet at 20 or 40% level. The analysed crude protein, ether extract, total ash, calcium, phosphorus, glucose and starch content of DORB-B and DORB-C were found at 19.0, 0.79, 17.05, 0.11, 1.92, 2.3, 11.22, and 15.02, 1.56, 13.0, 0.40, 2.76, 2.16, 19.0, respectively. The level of inclusion of DORB in diet appeared to exert a significant effect on the AME and AMEn values. When bioassayed at 20% inclusion level the DORB was found to have a significantly (p<0.01) lower value than that obtained at 40% inclusion level. However, no significant effect of age of quails on the AME values of DORB was evident. The ME bioassays with quails gave significantly (p<0.01) higher AME values for DORB-C than DORB-B thereby indicating that the continuous system of solvent extraction of rice bran is superior to the batch system from this point of view. The AME value of DORB predicted from its chemical composition also revealed that the DORB-C contained approximately 15% more energy than that in DORB-B.

Hydrogen Cyanide Produced by Pseudomonas chlororaphis O6 Exhibits Nematicidal Activity against Meloidogyne hapla

  • Kang, Beom Ryong;Anderson, Anne J.;Kim, Young Cheol
    • The Plant Pathology Journal
    • /
    • v.34 no.1
    • /
    • pp.35-43
    • /
    • 2018
  • Root-knot nematodes (Meloidogyne spp.) are parasites that attack many field crops and orchard trees, and affect both the quantity and quality of the products. A root-colonizing bacterium, Pseudomonas chlororaphis O6, possesses beneficial traits including strong nematicidal activity. To determine the molecular mechanisms involved in the nematicidal activity of P. chlororaphis O6, we constructed two mutants; one lacking hydrogen cyanide production, and a second lacking an insecticidal toxin, FitD. Root drenching with wild-type P. chlororaphis O6 cells caused juvenile mortality in vitro and in planta. Efficacy was not altered in the fitD mutant compared to the wild-type but was reduced in both bioassays for the mutant lacking hydrogen cyanide production. The reduced number of galls on tomato plants caused by the wild-type strain was comparable to that of a standard chemical nematicide. These findings suggest that hydrogen cyanide-producing root colonizers, such as P. chlororaphis O6, could be formulated as "green" nematicides that are compatible with many crops and offer agricultural sustainability.

Molecular Identification of Four Different α-amylase Inhibitors from Baru (Dipteryx alata) Seeds with Activity Toward Insect Enzymes

  • Bonavides, Krishna B.;Pelegrini, Patricia B.;Laumann, Raul A.;Grossi-De-Sa, Maria F.;Bloch, Carlos Jr.;Melo, Jorge A.T.;Quirino, Betania F.;Noronha, Eliane F.;Franco, Octavio L.
    • BMB Reports
    • /
    • v.40 no.4
    • /
    • pp.494-500
    • /
    • 2007
  • The endophytic bruchid pest Callosobruchus maculatus causes severe damage to storage cowpea seeds, leading to economical losses. For this reason the use of $\alpha$-amylase inhibitors to interfere with the pest digestion process has been an interesting alternative to control bruchids. With this aim, $\alpha$-amylase inhibitors from baru seeds (Dipteryx alata) were isolated by affinity chromatographic procedures, causing enhanced inhibition of C. maculatus and Anthonomus grandis $\alpha$-amylases. To attempt further purification, this fraction was applied onto a reversed-phase HPLC column, generating four peaks with remarkable inhibition toward C. maculatus $\alpha$-amylases. SDS-PAGE and MALDI-ToF analysis identified major proteins of approximately 5.0, 11.0, 20.0 and 55 kDa that showed $\alpha$-amylase inhibition. Results of in vivo bioassays using artificial seeds containing 1.0% (w/w) of baru crude extract revealed 40% cowpea weevil larvae mortality. These results provide evidence that several $\alpha$-amylase inhibitors classes, with biotechnological potential, can be isolated from a single plant species.

Fungicide Sensitivity among Isolates of Colletotrichum truncatum and Fusarium incarnatum-equiseti Species Complex Infecting Bell Pepper in Trinidad

  • Ramdial, Hema;Abreu, Kathryn De;Rampersad, Sephra N.
    • The Plant Pathology Journal
    • /
    • v.33 no.2
    • /
    • pp.118-124
    • /
    • 2017
  • Bell pepper is an economically important crop worldwide; however, production is restricted by a number of fungal diseases that cause significant yield loss. Chemical control is the most common approach adopted by growers to manage a number of these diseases. Monitoring for the development to resistance to fungicides in pathogenic fungal populations is central to devising integrated pest management strategies. Two fungal species, Fusarium incarnatum-equiseti species complex (FIESC) and Colletotrichum truncatum are important pathogens of bell pepper in Trinidad. This study was carried out to determine the sensitivity of 71 isolates belonging to these two fungal species to fungicides with different modes of action based on in vitro bioassays. There was no significant difference in log effective concentration required to achieve 50% colony growth inhibition ($LogEC_{50}$) values when field location and fungicide were considered for each species separately based on ANOVA analyses. However, the $LogEC_{50}$ value for the Aranguez-Antracol locationfungicide combination was almost twice the value for the Maloney/Macoya-Antracol location-fungicide combination regardless of fungal species. $LogEC_{50}$ values for Benomyl fungicide was also higher for C. truncatum isolates than for FIESC isolates and for any other fungicide. Cropping practices in these locations may explain the fungicide sensitivity data obtained.

Morphological, Phylogenetic and Biological Characteristics of Ectropis obliqua Single-Nucleocapsid Nucleopolyhedrovirus

  • Ma Xiu-cui;Xu Hai-Jun;Tang Mei-Jun;Xiao Qiang;Hong Jian;Zhang Chuan-Xi
    • Journal of Microbiology
    • /
    • v.44 no.1
    • /
    • pp.77-82
    • /
    • 2006
  • The tea looper caterpillar, Ectropis obliqua, is one of the major pests of tea bushes. E. obliqua single-nucleocapsid nucleopolyhedrovirus (EcobSNPV) has been used as a commercial pesticide for biocontrol of this insect. However only limited genetic analysis for this important virus has been done up to now. EcobSNPV was characterized in this study. Electron microscopy analysis of the occlusion body showed polyhedra of 0.7 to $1.7\;{\mu}m$ in diameter containing a single nucleocapsid per envelope of the virion. A 15.5 kb genomic fragment containing EcoRI-L, EcoRI-N and HindIII-F fragments, was sequenced. Analysis of the sequence revealed that the fragment contained eleven potential open reading frames (ORFs): lef-1, egt, 38.7k, rrl, polyhedrin, orfl629, pk-1, hoar and homologues to Spodoptera exigua multicapsid NPV (SeMNPV) ORFs 15, 28, and 29. Gene arrangement and phylogeny analysis suggest that EcobSNPV is closely related to the previously described Group II NPV. Bioassays on lethal concentration $(LC_{50}\;and\;LC_{90})$ and lethal time $(LT_{50}\;and\;LT({90})$ were conducted to test the susceptibility of E. obliqua larvae to the virus.

Constituents of the Fruits of Rumex japonicus with Inhibitory Activity on Aldose Reductase

  • Kim, Jong-Min;Jang, Dae-Sik;Lee, Yun-Mi;Lee, Ga-Young;Kim, Jin-Sook
    • Journal of Applied Biological Chemistry
    • /
    • v.51 no.1
    • /
    • pp.13-16
    • /
    • 2008
  • Five anthraquinones, emodin (1), ${\omega}$-hydroxyemodin (2), chrysophanol-8-O-${\beta}$-D-glucoside (3), emodin-8-O-${\beta}$-D-glucoside (4), and physcion-8-O-${\beta}$-D-glucoside (5), and five flavonoids, kaempferol-3-O-${\beta}$-D-glucoside (6), quercetin (7), quercitrin (8), isoquercitrin (9), and (+)-catechin (10), were isolated from the EtOAc-soluble extract of the fruits of Rumex japonicus. The structures of 1-10 were identified by spectroscopic methods including NMR studies. This is the first report on the isolation of compounds 3-5 from this plant. The isolates were subjected to in vitro bioassays to evaluate their inhibitory activities on the rat lens aldose reductase (RLAR), among which two anthraquinones (1 and 4), and five flavonols (5-9) showed significant activities on RLAR.

Bioassays of Polycyclic Aromatic Hydrocarbons in ZR-75-1 Human Breast Cancer Cells

  • Min, Kyung-N.;Sheen, Yhun-Y.
    • Environmental Mutagens and Carcinogens
    • /
    • v.23 no.1
    • /
    • pp.35-40
    • /
    • 2003
  • Polycyclic aromatic hydrocarbons (PAH) are frequently detected in food, water, soil, and sediment and are widespread environmental pollutants formed by the incomplete combustion of fossil fuels, woods and other organic matter. PAHs are considered to be probable human carcinogens. The mechanism of action of PAHs has been studied extensively, however it is not clear how PAHs turn on CYP1A1 in human breast cancer. Our laboratory have been studied the effect of PAHs in the human breast cancer cell MCF7. In this study, we examined the ZR-75-1 human breast cancer cells as a new system to evaluate bioactivity of PAHs. ZR-75-1 human breast cancer cell line responses to estrogen and progesteron. We have been able to estbilish long term culture system of this cells then used for the study to observe the effect of PAHs. We demonstrate that PAHs induced the CYP1A1 promoter and 7-ethoxyresolufin O-deethylase (EROD) activity in a concentration-dependant manner. RT-PCR analysis indicated that PAHs significantly up-regulate the level of CYP1A1 mRNA. Some of PAHs showed stronger stimulatory effect on CYP1 gene expression than TCDD. Apparently, ZR-75-1 cells have Aryl hydrocarbon receptors, therefore it would be good experimental tool to study the cross-talk between PAHs and steroid actions.

  • PDF

Sequestration and Bioavailability of Organopollutants in Soil;Their Implication to the Risk Assessment

  • Chung, Nam-Hyun;Lee, Il-Seok;Song, Hee-Sang;Bang, Won-Gi
    • Korean Journal of Environmental Agriculture
    • /
    • v.19 no.5
    • /
    • pp.442-449
    • /
    • 2000
  • The bioremediation is an economic technology to remove the organopollutants from soil. It is often found that the remediation could not remove the compounds below the levels determined by vigorous extractions as required by regulatory agencies. The reason for the reduced bioavailability with increasing time of aging has been accredited to the sequestration of the compounds in remote sites within or between soil particles. Then, the aging could be defined as the time-dependent sequestration. Partitioning and entrapment have been suggested as mechanism for aging. The rate and extent of the sequestration varies among dissimilar soils. The bioavailability of aged pollutants in soil could be measured by bioassays, mild solvent extraction, and soild-phase extractions. The sequestration could be affected by many factors including various soil properties, wetting and drying cycle, and the presence of cosolutes and NAPLs etc. The bioavailability and sequestration should be considered to determine the environmentally acceptable endpoint.

  • PDF

Effects of Cadmium, Copper, Chromium, Nickel, Silver, and Zinc on the Embryonic Development of the Sea Urchin, Strongylocentrotus intermedius (북쪽말똥성게 (Strongylocentrotus intermedius) 배아 (embryo)를 이용한 중금속에 대한 민감도 비교)

  • Ryu, Tae-Kwon;Hwang, In-Young;Lee, Taek-Kyun;Yoon, Jun-Heon;Lee, Chang-Hoon
    • Environmental Analysis Health and Toxicology
    • /
    • v.25 no.1
    • /
    • pp.19-26
    • /
    • 2010
  • Discharged materials from the point or non-point source are released into the sea, and as the results, marine environment is directly affected. We must estimate the impacts of contaminants to marine pollution rapidly and accurately. Therefore, it is needed on early warning system for appreciating marine environmental impacts, and required a bioassay to evaluate abnormal changes. A bioassay test was developed to examine the effects of heavy metal contaminants on the early life stages of the marine annimals. We have studied the effects of metals on early development of a sea urchin species, Strongylocentrotus intermedius. S. intermedius embryos were tested with six metals (Cu, Ag, Zn, Cd, Cr, Ni) and showed the highest sensitivity to Cu as well as the lowest sensitivity to Cd. The order of biological impact for metals was Cu>Ag>Ni>Zn>Cr>Cd. In accordance with the results, sea urchins embryos can provide biological criteria for seawater quality assessment. The sensitivity of developmental bioassay whith S. intermedius is at intermediate level among marine organisms commonly used in aquatic bioassays. And this sea urchin can be routinely employed as a test organism for ecotoxicity assays.

Effect of five PAHs (2-methylnaphthalene, fluorene, dibenzothiophene, phenanthrene, and pyrene) on the embryonic development in the mussel, Mytilus galloprovincialis (지중해담치, Mytilus galloprovincialis의 배 발생에 미치는 다환방향족탄화수소류 (2-methylnaphthalene, fluorene, dibenzothiophene, phenanthrene, pyrene) 의 영향)

  • Sung, Chan-Gyoung;Park, Pan-Soo;Lee, Jong-Hyeon;Lee, Chang-Hoon
    • The Korean Journal of Malacology
    • /
    • v.30 no.3
    • /
    • pp.177-187
    • /
    • 2014
  • Mussels have been commonly used in bioassay for quality assessments of environment. Moreover, several standard protocols for the developmental bioassay of bivalves have been proposed. In this study, the EC50 of polycyclic aromatic hydrocarbons (PAHs) was determined using mussel, Mytilus galloprovincialis embryonic developmental bioassay. To determine the sensitivity of M. galloprovincialis, their fertilized eggs were exposed to five PAHs (2-metylnaphthalene, fluorene, dibenzothiophene, phenanthrene, pyrene). The EC50 of 2-metylnaphthalene, fluorene, dibenzothiophene, phenanthrene, and pyrene were 232, 273, 67.9, 43.2, and $33.1{\mu}g/L$, respectively. The overall sensitivity of M. galloprovincialis in the present developmental bioassay was similar to or more sensitive than that of other marine organisms commonly used in aquatic bioassays. The results of this study could be provide with fundamental data of setting standard for protection of marine life and or can use prediction the aquatic toxicity of PAHs.