• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 3
  • 3
  • 1
  • Tagged with
  • 8
  • 3
  • 3
  • 3
  • 3
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Aspectos bioecológicos de Angiopolybia pallens (Lepeletier, 1836) (Hymenoptera-Vespidae) /

Cruz, Jucelho Dantas da. January 2006 (has links)
Orientador: Edilberto Gianotti / Banca: Fabio Prezoto / Banca: Gilberto Marcos de Mendonça Santos / Banca: Sulene Noriko Shima / Banca: Nivar Gobbi / Resumo: O presente trabalho foi realizado buscando o conhecimento de aspectos da biologia e ecologia de Angiopolybia pallens, uma importante espécie das matas úmidas brasileiras. Considerada uma espécie de alta freqüência em ambientes de Mata Atlântica do estado da Bahia, os dados coletados nos municípios de Vera Cruz-BA (12º 58’ S; 38º 36’ W Gr) e Ilhéus-BA (14º 47’ S and 39º 03’ W Gr) nos revelaram que: 1) essa vespa apresenta preferência por nidificar em folhas largas de arbustos e árvores de baixo porte (ninhos entre 0,30 e 3m do solo) localizadas em ambientes de meia sombra (clareiras e cultivos sombreados); 2) possui baixa autonomia de vôo, voando pequenas distâncias, com raio de ação efetivo de aproximadamente 24 metros e uma área de forrageamento de aproximadamente 1.800m2; 3) apresenta uma intensa atividade no início (6:00h às 7:00h) e fim do dia (17:30h às 18:00h) (ritmo circadiano bimodal); 4) tem baixo índice de eficiência na coleta de recursos, com uma equivalência entre os ítens coletados (néctar, presa e polpa); 5) reage negativamente à elevação da temperatura e luminosidade e positivamente ao incremento da umidade relativa do ar; 6) suas larvas possuem 3 ínstares e taxa de crescimento médio de 1,64; 7) suas colônias são poligínicas, sendo que, as vespas apresentam padrões de desenvolvimento ovariano variando de filamentoso a muito desenvolvido; 8) a casta das rainhas se diferencia significativamente da casta das operárias principalmente na fase de estabelecimento e 9) as castas das colônias em fase de estabelecimento são morfometricamente menores, quando comparadas com as de outras colônias com ciclo de desenvolvimento mais avançado / Abstract: The present work was carried out seeking to know aspects of the biology and ecology of Angiopolybia pallens, an important species of Brazilian rain forests. Regarded as a very frequent species in the environments of Atlantic Forest in the state of Bahia, the data collected in the cities of Vera Cruz, BA (12º 58’ S; 38º 36’ W Gr) and Ilhéus, BA (14º 47’ S and 39º 03’ W Gr) showed that: 1) this wasp prefers to nest on wide leaves of shrubs and short trees (nests between 0.30 and 3m from the ground) located in half-shaded environments (clearings and shaded cultures); 2) they have low flight autonomy and take flight for short distances, with an effective radius of action of about 24 meters and a foraging area of approximately 1,800m2; they exhibit intense activity at the beginning (from 6 to 7 a.m.) and the end of the day (from 5:30 to 6 p.m.) (bimodal circadian rhythm); they have a low efficiency rate in resource collecting, with equivalence among the items collected (nectar, prey and pulp); they react negatively to temperature or luminosity rising, and positively to increases in air relative humidity; 6) their larvae have three instars and an average growth rate of 1.64; 7) their colonies are polygynous, and the wasps show patterns of ovarian development ranging from filamentous to very well developed; 8) the queen caste differs significantly from the worker caste mainly in the establishment stage and 9) the castes of the colonies in the establishment stage are morphometrically smaller, if compared to the ones of other colonies with more advanced development cycles / Doutor
2

Mapeamento por hibridização in situ dos genes Lys Hsp70 e Hsp83 nos cromossomos meióticos do gafanhoto Schistocerca pallens (ACRIDIDAE)

Vasconcelos Oliveira Silva, Sandra January 2004 (has links)
Made available in DSpace on 2014-06-12T18:07:00Z (GMT). No. of bitstreams: 2 arquivo6328_1.pdf: 594892 bytes, checksum: ad966bc75b78fa320dbe40edeebed97e (MD5) license.txt: 1748 bytes, checksum: 8a4605be74aa9ea9d79846c1fba20a33 (MD5) Previous issue date: 2004 / Algumas espécies de gafanhotos são pragas milenares de áreas cultivadas em diversas regiões do mundo, provocando grandes prejuízos econômicos e ecológicos em períodos de explosão populacional. No Brasil, as espécies mais ameaçadoras, que causam danos significativos às lavouras e pastagens, são Rhammatocerus schistocercoides, Stiphra robusta e Schistocerca pallens, nenhuma das quais foi geneticamente bem caracterizada, apesar da grande importância prática. Neste trabalho foi iniciada a caracterização genética de S. pallens, através da localização por hibridização in situ dos genes Lys, Hsp70 e Hsp83 em cromossomos meióticos. Aproximadamente 700 núcleos foram analisados para os três genes e o percentual médio de marcação foi de 68,49%. Após análise de 108 núcleos marcados, com uma freqüência de 94,44% o gene Lys foi mapeado no cromossomo G1. O gene Hsp70 foi mapeado no cromossomo G2, onde foram observadas 89,94% das marcações do total de 199 núcleos marcados. Para o loco Hsp83 foram contados 163 núcleos marcados, dos quais 97,54% das marcações foram localizadas em um cromossomo médio identificado como M7. Para todos os genes hibridizados outras marcações foram observadas, mas todas em freqüências inferiores a 30%. Estes são os primeiros genes mapeados em S. pallens, sendo também os primeiros genes de cópia única mapeados na família Acrididae. Além de servir como novos marcadores para individualização cromossômica, os dados da localização destes genes poderão ser úteis como marcas físicas para um eventual programa de seqüenciamento genômico da espécie
3

Mechanisms regulating the thermal acclimation of dark respiration in snow tussock and ryegrass : a thesis submitted in partial fulfilment of the requirements for the degree of Master of Science in Biochemistry /

Clifford, Veronica R. January 2007 (has links)
Thesis (M. Sc.)--University of Canterbury, 2007. / Typescript (photocopy). Includes bibliographical references (leaves 107-118). Also available via the World Wide Web.
4

Aspectos bioecológicos de Angiopolybia pallens (Lepeletier, 1836) (Hymenoptera-Vespidae)

Cruz, Jucelho Dantas da [UNESP] 28 September 2006 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:35:44Z (GMT). No. of bitstreams: 0 Previous issue date: 2006-09-28Bitstream added on 2014-06-13T19:25:17Z : No. of bitstreams: 1 cruz_jd_dr_rcla.pdf: 3172449 bytes, checksum: 93adff1236d1e39f4809993c3217111e (MD5) / Universidade Estadual Paulista (UNESP) / O presente trabalho foi realizado buscando o conhecimento de aspectos da biologia e ecologia de Angiopolybia pallens, uma importante espécie das matas úmidas brasileiras. Considerada uma espécie de alta freqüência em ambientes de Mata Atlântica do estado da Bahia, os dados coletados nos municípios de Vera Cruz-BA (12º 58 S; 38º 36 W Gr) e Ilhéus-BA (14º 47 S and 39º 03 W Gr) nos revelaram que: 1) essa vespa apresenta preferência por nidificar em folhas largas de arbustos e árvores de baixo porte (ninhos entre 0,30 e 3m do solo) localizadas em ambientes de meia sombra (clareiras e cultivos sombreados); 2) possui baixa autonomia de vôo, voando pequenas distâncias, com raio de ação efetivo de aproximadamente 24 metros e uma área de forrageamento de aproximadamente 1.800m2; 3) apresenta uma intensa atividade no início (6:00h às 7:00h) e fim do dia (17:30h às 18:00h) (ritmo circadiano bimodal); 4) tem baixo índice de eficiência na coleta de recursos, com uma equivalência entre os ítens coletados (néctar, presa e polpa); 5) reage negativamente à elevação da temperatura e luminosidade e positivamente ao incremento da umidade relativa do ar; 6) suas larvas possuem 3 ínstares e taxa de crescimento médio de 1,64; 7) suas colônias são poligínicas, sendo que, as vespas apresentam padrões de desenvolvimento ovariano variando de filamentoso a muito desenvolvido; 8) a casta das rainhas se diferencia significativamente da casta das operárias principalmente na fase de estabelecimento e 9) as castas das colônias em fase de estabelecimento são morfometricamente menores, quando comparadas com as de outras colônias com ciclo de desenvolvimento mais avançado. / The present work was carried out seeking to know aspects of the biology and ecology of Angiopolybia pallens, an important species of Brazilian rain forests. Regarded as a very frequent species in the environments of Atlantic Forest in the state of Bahia, the data collected in the cities of Vera Cruz, BA (12º 58 S; 38º 36 W Gr) and Ilhéus, BA (14º 47 S and 39º 03 W Gr) showed that: 1) this wasp prefers to nest on wide leaves of shrubs and short trees (nests between 0.30 and 3m from the ground) located in half-shaded environments (clearings and shaded cultures); 2) they have low flight autonomy and take flight for short distances, with an effective radius of action of about 24 meters and a foraging area of approximately 1,800m2; they exhibit intense activity at the beginning (from 6 to 7 a.m.) and the end of the day (from 5:30 to 6 p.m.) (bimodal circadian rhythm); they have a low efficiency rate in resource collecting, with equivalence among the items collected (nectar, prey and pulp); they react negatively to temperature or luminosity rising, and positively to increases in air relative humidity; 6) their larvae have three instars and an average growth rate of 1.64; 7) their colonies are polygynous, and the wasps show patterns of ovarian development ranging from filamentous to very well developed; 8) the queen caste differs significantly from the worker caste mainly in the establishment stage and 9) the castes of the colonies in the establishment stage are morphometrically smaller, if compared to the ones of other colonies with more advanced development cycles.
5

Mechanisms regulating the thermal acclimation of dark respiration in snow tussock and ryegrass

Clifford, Veronica Rose January 2007 (has links)
The aim of this research was to identify the mechanisms that underpin changes in respiratory capacity during acclimation to temperature. Dark respiration, enzyme activities and leaf ultrastructure were measured from ryegrass (Lolium perenne) in controlled environmental chambers and two species of native grass (Chionochloa rubra & C. pallens) growing at different altitudinal ranges on Mount Hutt, Canterbury, New Zealand. The overall hypothesis was that the changes in both mitochondrial numbers and enzyme activity underpin the greater respiratory capacity observed in response to decreasing temperatures. Gas exchange measurements were carried out to measure rates of dark respiration (Rd) in leaves of both ryegrass and tussocks. Respiratory homeostasis (full acclimation) was achieved in ryegrass leaves but only partial acclimation in both species of tussock plants. Dark respiration rates for warm-grown ryegrass were greatly reduced compared to cool-grown grasses. Rd was lower for C. rubra growing at the base of the mountain (450m) compared to plants at a higher altitude (1060m). The dark respiration rates were also lower for C. pallens growing at 1070m than at 1600m. When comparing Rd between high and low altitude plants, it was significantly lower in low altitude plants at 450m than at 1600m. Oxygen consumption was measured in intact leaves and roots, crude mitochondria and isolated mitochondria from ryegrass to investigate whether a change in respiratory capacity was involved with changes in Rd. Mitochondrial respiratory capacity was slightly reduced in warm leaves and roots (not significantly). The respiratory capacity results from isolated mitochondria for C. rubra (at 450m and 1060m) and C. pallens (at 1070m and 1600m) were consistent with the hypothesis that plants from warm sites have lower respiratory capacity in comparison to plants from cool sites. Based on these results and those of previous studies, it was concluded that respiratory flux for any given temperature is not simply determined by maximal capacities of the respiratory apparatus but rather a combination of the availability of substrate supply, the demand for respiratory products (i.e. ATP) and/or the maximal capacity of respiratory enzymes. Utilizing transmission electron micrographs, it was found that mitochondria were significantly less abundant in warm-grown than cool-grown ryegrass mesophyll cells. Mitochondria dimensions increased slightly between the cool and warm treatment. At lower altitudes (C. rubra), there was a significant decrease in mitochondria numbers with decreasing elevation. At higher altitudes (C. pallens), there was no noticeable change in mitochondria numbers between 1070m and 1600m. It was concluded that mitochondrial abundance for the controlled and field experiments, and mitochondrial sizes in the field, were associated with changes in Rd. The maximal activities of fumarase and succinate dehydrogenase (SDH) in isolated mitochondria from leaves of ryegrass and tussock were measured spectrophotometrically. The results in the controlled experiment indicate that enzymes other than fumarase and SDH could be responsible for the increased respiratory capacity observed in cold acclimated leaves of ryegrass. However, fumarase maximal activity was significantly reduced in C. rubra at low altitude compared with C. pallens growing at high altitude - this suggests that it may be involved in the differences in respiratory capacity and Rd between the two sites. Succinate dehydrogenase did not differ significantly in response to altitude. The large difference between the two field sites for fumarase activity is comparable to the large difference in Rd and reduction in mitochondrial abundance and dimensions seen between the two sites. This supports the overall hypothesis that cool-grown plants keep up with energy demands at low temperatures by increasing enzyme concentrations/capacity. The results of this study are supportive of the hypothesis that growth in low altitudes and warm conditions will result in the reduction of Rd as a consequence of: (1) temperature sensitivity of the respiratory apparatus, resulting in the reduction of the respiratory capacities of mitochondria; (2) a reduction in mitochondria size and numbers; and as a consequence of this (3) a reduction in the activities of mitochondrial enzymes. However, these responses are species specific and vary according to the range of temperatures experienced by plants in the field and controlled environments.
6

Mechanisms regulating the thermal acclimation of dark respiration in snow tussock and ryegrass

Clifford, Veronica Rose January 2007 (has links)
The aim of this research was to identify the mechanisms that underpin changes in respiratory capacity during acclimation to temperature. Dark respiration, enzyme activities and leaf ultrastructure were measured from ryegrass (Lolium perenne) in controlled environmental chambers and two species of native grass (Chionochloa rubra & C. pallens) growing at different altitudinal ranges on Mount Hutt, Canterbury, New Zealand. The overall hypothesis was that the changes in both mitochondrial numbers and enzyme activity underpin the greater respiratory capacity observed in response to decreasing temperatures. Gas exchange measurements were carried out to measure rates of dark respiration (Rd) in leaves of both ryegrass and tussocks. Respiratory homeostasis (full acclimation) was achieved in ryegrass leaves but only partial acclimation in both species of tussock plants. Dark respiration rates for warm-grown ryegrass were greatly reduced compared to cool-grown grasses. Rd was lower for C. rubra growing at the base of the mountain (450m) compared to plants at a higher altitude (1060m). The dark respiration rates were also lower for C. pallens growing at 1070m than at 1600m. When comparing Rd between high and low altitude plants, it was significantly lower in low altitude plants at 450m than at 1600m. Oxygen consumption was measured in intact leaves and roots, crude mitochondria and isolated mitochondria from ryegrass to investigate whether a change in respiratory capacity was involved with changes in Rd. Mitochondrial respiratory capacity was slightly reduced in warm leaves and roots (not significantly). The respiratory capacity results from isolated mitochondria for C. rubra (at 450m and 1060m) and C. pallens (at 1070m and 1600m) were consistent with the hypothesis that plants from warm sites have lower respiratory capacity in comparison to plants from cool sites. Based on these results and those of previous studies, it was concluded that respiratory flux for any given temperature is not simply determined by maximal capacities of the respiratory apparatus but rather a combination of the availability of substrate supply, the demand for respiratory products (i.e. ATP) and/or the maximal capacity of respiratory enzymes. Utilizing transmission electron micrographs, it was found that mitochondria were significantly less abundant in warm-grown than cool-grown ryegrass mesophyll cells. Mitochondria dimensions increased slightly between the cool and warm treatment. At lower altitudes (C. rubra), there was a significant decrease in mitochondria numbers with decreasing elevation. At higher altitudes (C. pallens), there was no noticeable change in mitochondria numbers between 1070m and 1600m. It was concluded that mitochondrial abundance for the controlled and field experiments, and mitochondrial sizes in the field, were associated with changes in Rd. The maximal activities of fumarase and succinate dehydrogenase (SDH) in isolated mitochondria from leaves of ryegrass and tussock were measured spectrophotometrically. The results in the controlled experiment indicate that enzymes other than fumarase and SDH could be responsible for the increased respiratory capacity observed in cold acclimated leaves of ryegrass. However, fumarase maximal activity was significantly reduced in C. rubra at low altitude compared with C. pallens growing at high altitude - this suggests that it may be involved in the differences in respiratory capacity and Rd between the two sites. Succinate dehydrogenase did not differ significantly in response to altitude. The large difference between the two field sites for fumarase activity is comparable to the large difference in Rd and reduction in mitochondrial abundance and dimensions seen between the two sites. This supports the overall hypothesis that cool-grown plants keep up with energy demands at low temperatures by increasing enzyme concentrations/capacity. The results of this study are supportive of the hypothesis that growth in low altitudes and warm conditions will result in the reduction of Rd as a consequence of: (1) temperature sensitivity of the respiratory apparatus, resulting in the reduction of the respiratory capacities of mitochondria; (2) a reduction in mitochondria size and numbers; and as a consequence of this (3) a reduction in the activities of mitochondrial enzymes. However, these responses are species specific and vary according to the range of temperatures experienced by plants in the field and controlled environments.
7

The ecology of the reptiles and amphibians in the Burkea africana - Eragrostis pallens savanna of the Nylsvley Nature Reserve

Jacobsen, Niels Henning Guenther 03 November 2008 (has links)
Please read the abstract in the section, 00front, of this document / Dissertation (MSc)--University of Pretoria, 2008. / Zoology and Entomology / unrestricted
8

Sekundarni biomolekuli u vrstama Allium sect. Codonoprasum Rchb. – biološke aktivnosti, fitohemijski i hemotaksonomski aspekti / Secondary metabolites from selected species of genus Allium sect. Codonoprasum Rchb. – biological activities, phytochemical and chemotaxonomic aspects

Simin Nataša 30 January 2015 (has links)
<p>U ovoj doktorskoj disertaciji ispitan je hemijski sastav i biolo&scaron;ke aktivnosti<br />ekstrakata deset&nbsp; samoniklih&nbsp; taksona roda&nbsp; <em>Allium</em>&nbsp; sect.&nbsp;<em> Codonoprasum:&nbsp; A. carinatum</em>&nbsp;subsp. <em>pulchellum,&nbsp; A. carinatum&nbsp;</em> subsp. <em>carinatum,&nbsp; A. fuscum&nbsp;</em> var. <em>gracile,&nbsp; A. fuscum&nbsp;</em> var.&nbsp;<em>fuscum,&nbsp; A. flavum</em> subsp. <em>flavum,&nbsp; A. melanantherum,&nbsp; A. paniculatum&nbsp;</em> subsp.&nbsp;<em> marginatum,&nbsp;A. pallens</em>&nbsp; subsp. <em>tenuiflorum,&nbsp; A. oleraceum&nbsp; </em>i&nbsp;<em> A. rhodopeum</em>, sakupljenih na&nbsp; 27 lokaliteta&nbsp;u Srbiji. Cilj rada bio je da se dobiju podaci o sadržaju biolo&scaron;ki aktivnih jedinjenja u&nbsp;ovim, do sada veoma malo ispitanim vrstama roda&nbsp; <em>Allium</em>, i utvrdi njihova potencijalna&nbsp;lekovita vrednost.</p><p>Analiza hemijskog sastava obuhvatila je: analizu volatilnih komponenti svežih&nbsp;<br />lukovica primenom headspace GC-MS tehnike, kvalitativnu analizu metanolnih &nbsp;<br />ekstrakata primenom tečnohromatografskih metoda (LC-DAD-MS i LC-MS-MS), &nbsp;<br />kvantitativnu analizu odabranih fenolnih jedinjenja LC-MS-MS tehnikom,&nbsp; određivanje&nbsp;sadržaja ukupnih&nbsp; monomernih&nbsp; antocijana&nbsp; i određivanje aktivnosti aliinaze. Ispitivanja&nbsp;biolo&scaron;kih aktivnosti ekstrakata obuhvatila su: određivanje antioksidantne,&nbsp;antiinflamatorne, antimikrobne, antimutagene i genotoksične aktivnosti, kao i ispitivanje&nbsp;uticaja na rast zdravih i tumorskih ćelija i sposobnosti indukcije ćelijske smrti.&nbsp;</p><p>Sumiranjem dobijenih rezultata može se zaključiti da ispitivani predstavnici roda&nbsp;<br /><em>Allium&nbsp;</em> sect.&nbsp; <em>Codonoprasum&nbsp;</em> predstavljaju bogate izvore biolo&scaron;ki aktivnih jedinjenja sa&nbsp;&scaron;irokim spektrom biolo&scaron;kih aktivnosti. Sa hemotaksonomskog aspekta značajno je da se&nbsp;dimetil-disulfid&nbsp; izdvaja kao&nbsp; najdominantnija&nbsp; i često jedina&nbsp; isparljiva komponenta, da&nbsp;ekstrakti većine vrsta&nbsp; sadrže veliku količinu flavonoida (prvenstveno derivata&nbsp;kvercetina), da se vrste&nbsp;<em> A. pallens&nbsp;</em> i&nbsp; <em>A. oleraceum</em>&nbsp; izdvajaju od ostalih po tome &scaron;to ne&nbsp;sadrže rutin&nbsp; a sadrže&nbsp; hiperozid,&nbsp; da je vrsta&nbsp;<em> A. rhodopeum</em>&nbsp; siroma&scaron;na fenolnim&nbsp;jedinjenjima i da su sve vrste, osim vrste&nbsp; <em>A.&nbsp; flavum</em>, bogate antocijanima. Aktivnost&nbsp;aliinaze je visoka u svim ispitivanim vrstama. Većina ispitivanih ekstrakata, izuzev&nbsp;ekstrakata vrsta&nbsp; <em>A. carinatum&nbsp;</em>i <em>A. melanantherum</em>, pokazala je izraženu antioksidantnu&nbsp;aktivnost, dok su ekstrakti vrsta <em>A. flavum</em>, <em>A. rhodopeum</em>, <em>A. oleraceum </em>i <em>A. paniculatum&nbsp;</em>snažni antiinflamatorni agensi. Ekstrakti ispitivanih predstavnika sect.&nbsp;<em> Codonoprasum&nbsp;</em>nisu pokazali antimikrobnu i antimutagenu aktivnost. Takođe, ovi ekstrakti nisu ispoljili&nbsp;genotoksični efekat na ćelije zdravog tkiva (izuzev slabog genotoksičnog efekta ekstrakta&nbsp;nadzemnih delova&nbsp;<em> A. flavum</em>), &scaron;to ukazuje na bezbednost upotrebe vrsta sect.&nbsp;<em>Codonoprasum&nbsp;</em> kao hrane ili u obliku lekova. Ekstrakti celih biljaka&nbsp;<em>A. paniculatum</em> i <em>A.&nbsp;rhodopeum</em>, kao i ekstrakt nadzemnih delova &nbsp;<em>A. melanantherum</em>&nbsp; pokazali su snažnu&nbsp;antiproliferativnu aktivnost sa povoljnim ne-tumor/tumor koeficijentima i indukovali&nbsp;apoptozu u tumorskim ćelijama, iz čega se može zaključiti da imaju visok potencijal&nbsp;primene u antitumorskoj terapiji.&nbsp;</p> / <p>In the present doctoral thesis the chemical composition and biological activities&nbsp; of&nbsp;<br />10 wild growing taxa of genus&nbsp; <em>Allium</em>&nbsp; sect. <em>Codonoprasum</em>&nbsp; (<em>A. carinatum&nbsp;</em> subsp.&nbsp;<br /><em>pulchellum,&nbsp; A. carinatum&nbsp;</em> subsp.&nbsp; <em>carinatum,&nbsp; A. fuscum&nbsp;</em> var.&nbsp; <em>gracile,&nbsp; A. fuscum</em>&nbsp; var.&nbsp;<br /><em>fuscum,&nbsp; A. flavum&nbsp;</em> subsp.&nbsp; <em>flavum,&nbsp; A. melanantherum,&nbsp; A. oleraceum,&nbsp; A. paniculatum</em><br />subsp. <em>marginatum, A. pallens</em> subsp. <em>tenuiflorum</em> and <em>A. rhodopeum</em>) were investigated.&nbsp;The samples were&nbsp; collected from 27 locations in Serbia. The aim of the study was to&nbsp;obtain data on the content of biologically active compounds in extracts of &nbsp;these&nbsp;unexplored species of the genus Allium and to determine their potential medicinal value.</p><p>Phytochemical caracterisation included: headspace GC-MS analysis of fresh bulb&nbsp;<br />volatiles, LC-DAD-MS and LC-MS-MS qualitative analysis of methanol extracts, LC-MS-MS quantitative analysis of 44 selected phenolic compounds in methanol extracts,&nbsp;determination of total monomeric anthocyanins content and alliinase activity. In order to&nbsp;assess the biological potential of methanol extracts, the antioxidant, anti-inflammatory,&nbsp;antimicrobial, antimutagenic, genotoxic and antiproliferative activities of &nbsp;the extracts&nbsp;were studied.</p><p>Summing up all the results obtained, it can be concluded that species of genus&nbsp;<em>Allium&nbsp;</em> sect.&nbsp; <em>Codonoprasum&nbsp;</em> are rich sources of biologically active compounds with a&nbsp;broad spectrum of biological activities. Dimethyl disulfide is the most dominant and&nbsp;often the only volatile component of most species, which is significant from&nbsp;chemotaxonomic point of view. The methanol extracts of investigated species contain&nbsp;high levels of flavonoids (primarily quercetin derivatives). Specificity of&nbsp; <em>A. pallens</em>&nbsp; and&nbsp;<em>A. &nbsp;oleraceum</em>&nbsp; extracts is that they do not contain rutin, but contain hyperoside, while&nbsp;small quantity of phenolic compounds&nbsp; is characteristic for&nbsp; <em>A. rhodopeum</em>&nbsp; extract. All&nbsp;investigated species, except of <em>A. flavum</em>, are rich in anthocyanins. Alliinase activity was&nbsp;high in&nbsp; all examined species. Most of the extracts, except&nbsp; <em>A. carinatum</em>&nbsp; and&nbsp; <em>A.&nbsp;melanantherum</em>&nbsp; extracts, express considerable antioxidant activity, &nbsp;while extracts of&nbsp;<em> A.&nbsp;flavum</em>,&nbsp; <em>A. rhodopeum</em>,&nbsp; <em>A. paniculatum</em>&nbsp; and&nbsp; <em>A. oleraceum&nbsp;</em> are potent anti-inflammatory&nbsp;agents. The investigated&nbsp; <em>Allium</em>&nbsp; extracts did not show antimicrobial and antimutagenic&nbsp;activity. Also, the extracts did not express genotoxic effect on healthy tissue cells&nbsp;(except the weak genotoxic effects of aerial parts extract of&nbsp; <em>A. flavum</em>), indicating that&nbsp;the use&nbsp; of these species as a food or as a drug is safe. Whole plant extracts of&nbsp; <em>A.&nbsp;paniculatum</em>&nbsp; and&nbsp;<em> A. rhodopeum</em>, as well as aerial parts extract of&nbsp;<em> A. melanantherum</em>&nbsp;showed strong antiproliferative activity (with a favorable &nbsp;non-tumor/tumor ratios) and&nbsp;induced apoptosis in tumor cells, suggesting that these plants have a high potential for&nbsp;application in antitumor therapy.</p>

Page generated in 0.0634 seconds