Effect of Different Mutagens on Some Mineral, Phytochemical and Proximate Composition of Two Red Pepper Varieties

Aim: This research was designed to evaluate the effects of different levels of three mutagens on two pepper varieties with a vision of choosing mutants with high values in biochemical contents that may possibly be valuable in breeding improved varieties of the plant. Methods: Seeds of pepper were exposed to varying doses of gamma rays 60Co (50, 100, 150, and 200Gy), X-ray doses (40, 60, 80, and 100KV) and sodium azide (0.01, 0.02, 0.03 and 0.04%). The treated seeds and the controls were grown in the Botanic Garden of the University of Nigeria, Nsukka using a Completely Randomized Design. Results: The result showed that vitamin C and β-carotene ranged from 5.89 – 26.88 and 2.62 – 11.35 mg/100 g, Fe and Ca (14.70 and 13.78 mg/100 g) were highest in Shombo at 100Gy. Values ranging from 0.36-2.00 and 3.96 – 18.82 mg/100 g were recorded for flavonoid and alkaloid content across all treatment combinations. The result also revealed that at 100Kv and 150Gy, ash content increased in both varieties. The highest protein concentration of 9.57% was recorded at 100Kv of X-ray in Shombo and 6.96% at 150Gy of gamma irradiation in Tatase variety. Principal component analysis explained extracted five principal axis which accounted for the variability of 72.54%. Conclusion: This study reveals that biochemical content in pepper could be improved with exposure to mutagens especially gamma irradiation.

Improvement of clavulanic acid production in Streptomyces clavuligerus F613-1 by using a claR-neo reporter strategy

Background: Streptomyces clavuligerus was the producer of clavulanic acid, claR, a pathway-specific transcriptional regulator in S. clavuligerus, positively regulates clavulanic acid biosynthesis. In this study, the promoter-less kanamycin resistance gene neo was fused with claR to obtain strain NEO from S. clavuligerus F613-1. The claR-neo fusion strain NEO was mutated using physical and chemical mutagens and then screened under high concentrations of kanamycin for high-yield producers of clavulanic acid. Results: The reporter gene neo was fused downstream of claR and used as an indicator for expression levels of claR in strain NEO. After three rounds of continuous treatment and screening, the high-yield clavulanic acid-producing strain M3-19 was obtained. In the shaking flask model, the clavulanic acid titer of M3-19 reached 4.33 g/L, which is an increase of 33% over the titer of 3.26 g/L for the starting strains S. clavuligerus F613-1 and NEO. Conclusions: Our results indicate that neo can be effectively used as a reporter for the expression of late-stage biosynthetic genes when screening for high-yield strains and that this approach has strong potential for improving Streptomyces strains of industrial value.

Cuantificación de los hidrocarburos aromáticos policíclicos (hap) en el material particulado pm 2. 5 de una zona residencial de pamplona, Colombia / Quantification ff polycyclic aromatic hydrocarbons (pahs) in particulate matter pm 2. 5 in a residential area of pamplona, Colombia

Los contaminantes del aire han sido, y siguen siendo, los principales factores que contribuyen a enfermedades pulmonares obstructivas crónicas (EPOC), enfermedades cardiovasculares (ECV), asma y cáncer. El ozono, los óxidos de azufre, monóxido de carbono, óxidos de nitrógeno y el material particulado constituyen los contaminantes del aire. En este estudio se realizó la cuantificación de hidrocarburos aromáticos policíclicos (HAP) presentes en muestras de material particulado fracción respirable PM2.5 del aire de la ciudad de Pamplona (Norte de Santander, Colombia). Inicialmente la materia orgánica presente en el material particulado PM2.5 se extrajo por ultrasonido, seguido de la concentración por rotaevaporación, obteniéndose el extracto global, parte del cual se sometió a un proceso de fraccionamiento en una columna de silicagel. Finalmente se obtienen cuatro fracciones. La cuantificación de los HAP presentes en el material particulado PM2.5, el extracto global y las cuatro fracciones se realizó en un cromatógrafo de gases Agilent 6890 plus con detector FID. Entre los HAP identificados se encuentran: naftaleno, fluoreno, fenantreno, benzo(a)antraceno, pireno, dibenzo(a,h)antraceno e indeno(1,2,3,cd)pireno, estos HAP son compuestos tóxicos, mutágenos y carcinógenos para los animales y los seres humanos según la agencia internacional de investigación del cáncer (IARC).

Air pollutants have been. and still are. the main factor that contribute to chronic obstructive pulmonary disease (COPD), cardiovascular disease (CVD), asthma and cancer. Ozone, sulfur oxides, carbon monoxide, nitrogen oxides and particulate matter are air pollutants. Quantification of polycyclic aromatic hydrocarbons (PAHs) present in samples of particulate matter breathable fraction PM2.5 air of the city of Pamplona (Norte de Santander, Colombia) was performed in this study. Initially, organic material present in the particulate material PM2.5 was extracted through ultrasound, followed by concentration through a rotary evaporator, obtaining the overall extract, part of which was subjected to a division process in a silica gel column, Finally four fractions were obtained. Quantification of PAHs present in the PM2.5 particulate material, global extract and the four fractions was carried out in an Agilent 6890 gas chromatograph plus with FID detector. Among the HAPs identified the following are included: naphthalene, fluorene, phenanthrene, benzo(a)anthracene, pyrene, dibenzo(a,h)anthracene and indene(1,2,3,cd-pyrene). These PAHs are toxic compounds, mutagenic and carcinogenic for animals and humans according to the International Agency for Research on Cancer (IARC).

Interacciones genotóxicas de mutágenos en mezclas binarias mediante ensayo cometa alcalino en linfocitos humanos / Interaction of mutagens in binary mixtures using the alkaline comet assay in human lymphocytes

Introducción. Los mutágenos contenidos en mezclas complejas presentan interacciones de sinergismo, aditivas o antagónicas. Se han desarrollado enfoques experimentales que permitan dilucidar el responsable de las interacciones en la mezcla. Objetivo. Desarrollar un diseño experimental para comprender los procesos que se llevan a cabo entre los compuestos presentes en las mezclas complejas. Materiales y métodos. Se expusieron linfocitos humanos a mezclas binarias de mutágenos B[a]P, DMBA, Trp-P-1 y MX durante una hora, con activación metabólica y sin ella. La viabilidad se evaluó con azul de tripano y, la genotoxicidad, con cometa alcalino. Resultados. Ningún hidrocarburo tuvo efecto con furanona. Con S9 y sin él, se observó que se presentaban interacciones tóxicas entre hidrocarburos. Se observó sinergismo sin S9 entre B[a]P y Trp-P-1 y, con actividad metabólica, entre DMBA y Trp-P-1. Sin S9 se observó interacción antagónica entre Trp-P-1 y DMBA y, con S9, entre Trp-P-1 y MX y entre MX y DMBA. Se observó un incremento dependiente de la dosis en la longitud de la cola. Hubo daño genotóxico medio y aumento de las células dañadas. Para todas las mezclas se pudo determinar la concentración mínima en la que se observaban efectos adversos y solo para algunas se determinó la concentración máxima en la cual no se observaron efectos adversos. Conclusión. Se hace un aporte para comprender los procesos que ocurren cuando en una mezcla hay presentes, al menos, dos mutágenos y se valida un modelo de análisis que permite dilucidar el compuesto que tiene efecto sobre otro. También, se demostró que según el tipo de compuestos en la mezcla, se tendrá o no un umbral de riesgo.

Introduction. Mutagens contained in complex mixtures can present synergistic interactions, either additive or antagonistic. Therefore, development of experimental approaches is necessary to elucidate which is the responsible agent for the effect in the mixtures. Objective. An experimental design was developed that allowed an understanding of the processes between the compounds of complex mixtures. Materials and methods. Human lymphocytes were exposed to binary mixtures of the mutagens B[a]P, DMBA, Trp-P-1 and MX for 1 hour with or without S9. Viability was assessed with trypan blue dye and the genotoxicity by the comet assay. Results. All of the hydrocarbon showed an effect with furanone. With and without S9, the most toxic interactions were observed between hydrocarbons. Synergistic interaction was observed without S9 between B [a] P and Trp-P-1 and between DMBA and Trp-P-1 with metabolic activity. Without S9 antagonistic interaction was observed only between Trp-P-1+DMBA, and with S9 between Trp-P-1+MX and MX+DMBA. It observed an increase dose dependent in tail length. Half the cultures showed genotoxic damage and increased cell damage. For each mixture, minimum concentrations were determined at which adverse effects are observed; for some only the maximum concentration was determined at which no adverse effects are observed. Conclusion. The processes between mutagens present in a mixture have become better understood, and the results validated an analytical model that determined which component had an effect on another. The results also showed that the type of compounds in the mixture determined whether or not a risk threshold was present.

Daño celular en una población infantil potencialmente expuesta a pesticidas / Cell Damage in a Pediatric Population Potentially Exposed to Pesticides

Los pesticidas pueden producir efectos agudos o crónicos en la salud humana. Muchos de ellos pueden provocar daño en el material genético. Esta modificación en la información genética se ha relacionado con un alto riesgo de padecer cáncer. El objetivo del presente trabajo es indagar el daño en el material genético de una población infantil expuesta potencialmente a pesticidas en el ambiente. El diseño metodológico fue de tipo observacional y transversal. Participaron en el estudio 48 niños expuestos potencialmente a pesticidas y 46 niños no expuestos. Se obtuvo muestra de la mucosa bucal para determinar daño en el material genético a través de la frecuencia de micronúcleos (MN). Se encontró en el grupo expuesto potencialmente a pesticidas un promedio mayor de micronúcleos (5,1±2,9 vs 1,8±2,0; p<0,0001), un promedio mayor de células binucleadas, (3,5±2,7 vs 1,4±1,4; p<0,0001), mayor frecuencia de cariorrexis (18,2±18,4 vs 5,8±18,4; p<0,004) y picnosis (24,8± 18,0 vs 17,1±8,3; p<0,03). El 40% (19/47) de los niños expuestos potencialmente a pesticidas tuvieron un tiempo de exposición de 6 años. Esta investigación aporta evidencias de daño genético en la población expuesta potencialmente a pesticidas en el ambiente Palabras claves: Genotoxicidad- pesticidas -niños-medio ambiente.

Pesticides can cause acute or chronic effects on human health. Many pesticides can cause damage to genetic material. These changes in genetic information have been associated with an increased risk of cancer. The objective of this study is to investigate damage to genetic material in a population of children potentially exposed to pesticides in the environment. The study design was observational and cross sectional. We studied 48 children potentially exposed to pesticides and 46 unexposed children. Samples of the oral mucosa were obtained to determine damage to genetic material using micronucleus frequency (MN).Higher average micronucleus counts were found in the group potentially exposed to pesticides (5.1±2.9 vs. 1.8±2.0, p <0.0001), along with a higher average of binucleate cells (3.5±2.7 vs. 1.4±1.4 p <0.0001), higher frequency of karyorrhexis (18.2±18.4 vs. 5.8± 18.4, p <0.004) and pyknosis (24.8±18.0 vs. 17.1±8.3; p <0.03).Of the children potentially exposed to pesticides, 40% (19/47) had an exposure time of 6 years. This study provides evidence of genetic damage in the population potentially exposed to pesticides in the environment.

Daño celular en una población infantil potencialmente expuesta a pesticidas / Cell damage in a pediatric population potentially exposed to pesticides

Los pesticidas pueden producir efectos agudos o crónicos en la salud humana. Muchos de ellos pueden provocar daño en el material genético. Esta modificación en la información genética se ha relacionado con un alto riesgo de padecer cáncer. El objetivo del presente trabajo es indagar el daño en el material genético de una población infantil expuesta potencialmente a pesticidas en el ambiente. El diseño metodológico fue de tipo observacional y transversal. Participaron en el estudio 48 niños expuestos potencialmente a pesticidas y 46 niños no expuestos. Se obtuvo muestra de la mucosa bucal para determinar daño en el material genético a través de la frecuencia de micronúcleos (MN). Se encontró en el grupo expuesto potencialmente a pesticidas un promedio mayor de micronúcleos (5,1±2,9 vs 1,8±2,0; p<0,0001), un promedio mayor de células binucleadas, (3,5±2,7 vs 1,4±1,4; p<0,0001), mayor frecuencia de cariorrexis (18,2±18,4 vs 5,8±18,4; p<0,004) y picnosis (24,8± 18,0 vs 17,1±8,3; p<0,03). El 40% (19/47) de los niños expuestos potencialmente a pesticidas tuvieron un tiempo de exposición de 6 años. Esta investigación aporta evidencias de daño genético en la población expuesta potencialmente a pesticidas en el ambiente.

Pesticides can cause acute or chronic effects on human health. Many pesticides can cause damage to genetic material. These changes in genetic information have been associated with an increased risk of cancer. The objective of this study is to investigate damage to genetic material in a population of children potentially exposed to pesticides in the environment. The study design was observational and cross sectional. We studied 48 children potentially exposed to pesticides and 46 unexposed children. Samples of the oral mucosa were obtained to determine damage to genetic material using micronucleus frequency (MN).Higher average micronucleus counts were found in the group potentially exposed to pesticides (5.1±2.9 vs. 1.8±2.0, p <0.0001), along with a higher average of binucleate cells (3.5±2.7 vs. 1.4±1.4 p <0.0001), higher frequency of karyorrhexis (18.2±18.4 vs. 5.8± 18.4, p <0.004) and pyknosis (24.8±18.0 vs. 17.1±8.3; p <0.03).Of the children potentially exposed to pesticides, 40% (19/47) had an exposure time of 6 years. This study provides evidence of genetic damage in the population potentially exposed to pesticides in the environment.

A comparison of the effects of physical and chemical mutagens in sesame (Sesamum indicum L.)

Three sesame genotypes (Rama, SI 1666 and IC 21706) were treated with physical (γ-rays: 200 Gy, 400 Gy or 600 Gy) or chemical (ethyl methane sulphonate, EMS: 0.5 percent, 1.0 percent, 1.5 percent or 2.0 percent) mutagens and their mutagenic effectiveness and efficiency were estimated in the M2 generation. The M3 generation was used to identify the most effective mutagen and dose for induction of mutations. The average effectiveness of EMS was much higher than γ-rays. The lowest dose of γ-rays (200 Gy) and the lowest concentration of EMS (0.5 percent) showed the highest mutagenic efficiency in all genotypes. Analysis of the M3 generation data based on parameters such as the variance ratio and the difference in residual variances derived from the model of Montalván and Ando indicated that 0.5 percent concentration of EMS was the most effective treatment for inducing mutations.

Qualidade fisiológica de sementes de arroz submetidas à radiação gama / Physiological quality rice seed submitted to gamma radiation

O objetivo deste trabalho foi avaliar os efeitos da radiação gama (Co60) na qualidade fisiológica de sementes de arroz. O estudo foi realizado em três ensaios. No primeiro ensaio, sementes de arroz foram irradiadas com doses de 0; 1; 2,5 e 5Gy e, para o segundo e o terceiro ensaio, as sementes foram submetidas a envelhecimento acelerado, antes da irradiação. No segundo ensaio, as sementes foram dividas em úmidas e secas após envelhecimento acelerado e, então, foram irradiadas nas doses 0; 1; 2,5 e 5Gy. No terceiro ensaio, as sementes foram secas após o envelhecimento acelerado e irradiadas com doses de 0, 10, 25 e 50Gy. Para avaliação dos efeitos fisiológicos da radiação gama, foram realizados teste de germinação - TG, índice de velocidade de germinação - IVG e crescimento de plantas (comprimento de parte aérea e sistema radicular e massa seca total), em todos os ensaios. Foram determinadas as atividades enzimáticas da fosfatase ácida e alfa amilase nas sementes secas, no segundo ensaio. Os resultados obtidos nos ensaios indicam que as doses de radiação gama estudadas não afetam a qualidade fisiológica das sementes de arroz.

The objective of this research was to evaluate the effects of the gamma radiation (Co60) on the physiological quality of rice seeds. The research was carried out through three tests; in the first test rice seeds were irradiated at dosages of 0; 1; 2.5 and 5Gy, while for the second and third tests the seeds were subjected to accelerated aging before being irradiated. For the second test the seeds were divided into wet and dry and both groups subjected to accelerated aging previous to irradiation at dosages of 0; 1; 2.5 and 5Gy. For the third test the seeds were dried after being subjected to accelerated aging, and then irradiated at dosages of 0, 10, 25 and 50Gy. To assess the physiological effects of the gamma radiation, all seeds were tested for germination and their germination speed index recorded. Seedling growth was graded through the measurement of the lengths of the first leaf and seminal root system and total seedling dry weight, across all tests. The enzymatic activity of acid phosphatase and alpha-amylase was measured on dry seeds from the second test. The results from all tests indicate that the applied gamma radiation dosages did not cause any changes to the physiological quality of rice seeds.

Efecto genotóxico y mutagénico de contaminantes atmosféricos / Genotoxic and mutagenic effect of atmospheric pollutants

Cada día, con los avances de la industria, las zonas urbanas incrementan la concentración y número de contaminantes, por ende, se exceden los valores permisibles (100 mg/m3) y se altera la sensibilidad de los organismos y se crean las condiciones para desarrollar mutaciones y cáncer. Históricamente, la exposición del hombre a una gran variedad de mezclas complejas se ha asociado con el aumento del riesgo para generar mutaciones y cáncer. La contribución sobre el riesgo para la salud, que ejerce la contaminación atmosférica, presenta dificultades en la identificación de los componentes tóxicos de las mezclas complejas y el poco conocimiento acerca del comportamiento de las sustancias genotóxicas encontradas en ellas.

Everyday, with industrial development, urban zones increase the amounts and concentrations of pollutants , frequently rising beyond their permissible values (100mg/m3) and modifying the organisms’ sensitivity and their possibility of developing mutations and cancer. Historically, human exposures to a variety of complex mixtures have been associated with an increased risk for cancer. Risk assessment in health of complex environmental samples suffers from difficulty in identifying toxic components, inadequacy of available toxicity data, and a paucity of knowledge about the behavior of genotoxic substances in complex mixtures.

Antagonism of Chinese medicine herbals on chromsome breakage induced by Bleomycin / 吉林大学学报(医学版)

Objective To study the antagonsim of Chinese medicine herbals on the chromsome breakage induced by Bleomycin(BLM),which was composed of ginseng,cortex acanthopanasia radices(CAR),pachyna cocos Fr.and angelica at certain concentration.Methods The mutagen sensitivety test was used to detect the effect of BLM on chromatid breaks per cell from peripheral blood lymphocytes of 20 healthy subjects.And the infuence of Chinese medical herbals on the stability of chromsome was studied.50 cells per sample were observed under microscope and then the average b/c value(chromatid breaks per cell) of every group was calculated.The all b/c values were analyzed by statistical method.Results There was obvious difference of the b/c value between BLM group and negative group(P

Study on mutation in V_(79) cells and transformation in NIH/3T3 cells induced by the extract 261-B_2-3 of Alternaria alternata / 中国病理生理杂志

The extract 261-B_2-3 of Alternaria alternata isolated from the corn in Linxian county which is an area with high incidence of esophageal cancer induced 6-thioguanine-resistant mutants in V_(79) cells and transformation in NIH/3T3 cells. There is mutation activity in presence or absence of rat-liver-microsome prepar-ations. Treated with a range of eoncentration(32ug/ml, 64ug/ml, 128ug/ml) of the extract, high rate of transformation different from the rate treated by solvent control, is found.The results show that this extract contains direct mutagen. The high infestationincidence of Alternaria alternata in the corn of Linxian county might play an important role in the causation ofesophageal cancer in this area.

Study on unscheduled DNA synthesis of Alternaria alternata 261-B2-3 in human amnionic cells in vitro / 中国病理生理杂志

Tne Unscheduled DNA syntheris (UDS) was induced in cultured human amnionic cell line FL in vitro by exposure to 261-B2-3, an extract of Alternaria alternata separated from crops in Linxian county which is a high risk area of esophageal cancer in China. In the absence of S-9M, 261-B2-3 was capable of inducing UDS in target cells and the ratio of UDS elicited by the extract (the range of concentration being 10~(-6) to 10~(-3) mg/ml) was significatly different from the ratio by solvent control (P0.05) with S-9M. The results demonstrated that 261-B2-3 has stronger mutagenicity without S-9M and it's mutagenicity is rising with increasing concentrations in a certain range. On the contrary, 261-B2-3 has no or only a weak mutagenicity with S-9M. It is suggested that there arc direct mutagens in this extract. It is possible that Alternaria alternata contaminated the crops play an important role in the high incidence of esophageal cancer in Linxian county.

EFFECTS OF INTERFERON ON MITOMYCIN-INDUCED SISTER CHROMATID EXCHANGES AND ON ULTRAVIOLET-LIGHT-INDUCED UNSCHEDULED DNA SYNE THESIS / 第二军医大学学报

We studied the effects of interferon(IFN) on sister chromatid exchanges(SCE) induced by mitomycin(MMC) and/or on unscheduled DNA synthesis(UDS ) induced by ultraviolet light(UV) in peripheral lymphocytes taken from 4 normal individuals and 3 patients with xeroderma pigmentosum(XP) in whom the existence of congenital DNA excision repair defect had been verified.The lymphocytes from 2 normal individuals and 3 patients with XP were treated with IFN 8 hours before MMC was added SCE frequencies in IFN groups were lower than those in the controls. Statistical computation showed that all differences were highiy significant(P0.05).