ABSTRACT Cassava is a known source of linamarin, but difficulties associated with its isolation have prevented it from being exploited as a source. A batch adsorption process using activated carbon at the appropriate contact time proved successful in its isolation with ultrafiltration playing a pivotal role in the purification process. Result revealed that optimum purification was obtained with increasing amount of crude cassava extract (CCE) purified. 60g of CCE took 32 mins, 80 g, 34 mins while 100 g took 36 mins of contact time, where 1.7 g, 2.0 g and 2.5 g of purified product were obtained, respectively. The purification process in batch mode was also carried out at different temperatures ranging from 25 to 65oC. Results showed that purification increases with increase in temperature. In a bid to ascertain the moles of linamarin adsorbed per pore volume of activated carbon used, the composite isotherm was found to represent the measured adsorption data quite well. The adsorption of linamarin was used to study the goodness of fit criteria (R2) for the entire process. Results showed that R2 value was best with decreasing amount of CCE purified (R2=1 for 60 g) at the temperature of 45oC. Compound elucidation of purified product by Picrate paper test, IR and 1HNMR confirmed the structure of linamarin. Cytotoxic effects of linamarin on MCF-7, HT-29, and HL-60 cells were determined using the 3 - (4, 5 – dimethylthiazol-2-yl) – 2, 5 – diphenyltetrazolium bromide (MTT) assay. Cytotoxic effects were significantly increased in the presence of linamarase, which catalysed the hydrolysis of linamarin to hydrogen cyanide. A 10–fold decrease in the IC50 values obtained for linamarin or crude extract in the presence of linamarase was determined for HL-60 cells. This study thus describes a method for the isolation and purification of linamarin from cassava, as well as the potential of this compound as an anticancer agent.

1. Colorimetric Assay for Cyanide and Cyanogenic Glycoside Using Polysorbate 40-Stabilized Gold Nanoparticles. This study described a simple and homogeneous method for the selective and sensitive detection of cyanide and endogenous biological cyanide using polysorbate 40-stabilized gold nanoparticles (PS 40-AuNPs). Neutral PS 40 molecules enable citrate-capped AuNPs to stabilize in a high-salinity solution. The addition of cyanide to a solution of PS 40-AuNPs resulted in the formation of AuCN(s) on the NP surface and Au(CN)2¡V in an aqueous solution. The removal of PS 40 molecules from the NP surface rendered the AuNPs unstable in a high-salinity solution, leading to NP aggregation. The formation of AuCN(s) and Au(CN)2¡V was demonstrated by means of surface-assisted laser desorption/ionization time of flight mass spectrometry and inductively coupled plasma mass spectroscopy, respectively. PS 40-AuNPs were capable of selectively detecting cyanide at concentrations as low as 500 nM. Additionally, the minimum detectable concentration of linamarin (cyanogenic glycoside) was measured to be 1 uM using PS 40-AuNPs. This probe was successfully applied to the determination of cyanide in tap water, the monitor of cyanide removal during food processing, and the quantification of linamarin in cassava root. 2. Colorimetric detoxification and monitored cyanogenic glycoside in plants/fruit using polysorbate 40-stabilized gold nanoparticles. Developing rapid, highly sensitive, and selective detection/inhibition of cyanide/cyanogenic glycoside from plants and foods is extremely essential for human life safety. Here we report a strategy for the colormetric visualization of cyanogenic glycoside using polysorbate 40 stabilized gold nanoparticle (PS 40-AuNPs). Two cyanogenic glycosides (amygdalin and linamarin) were chosen to determine the efficiency of acid hydrolysis. According to US Department and Health and Human Services standard cyanide antidote kit, sodium thiosulfate and hydroxocobalamin (vitamin B12a) seems to be an appropriate antidote for treatment cyanide poisoning victims. The addition of thiosulfate/vitamin B12a to a solution of cyanide/cyanogenic glycosides resulted in the formation of thiocyanate/vitamin B12 in an aqueous solution, which couldn¡¦t etch PS 40-AuNPs and inhibit the aggregation of PS 40-AuNPs in a high-salt solution. The inhibition/detoxification efficiency (IC50) of thiosulfate and vitamin B12a were studied for treatment of cyanide and hydrolyzed cyanogenic glycoside. This probe was also used to monitor the removal of cyanide, estimated the concentration of cyanide and detoxification of cyanide by thiosulfate in plants/fruit sample.

Made available in DSpace on 2014-06-11T19:24:41Z (GMT). No. of bitstreams: 0 Previous issue date: 2001-07Bitstream added on 2014-06-13T19:31:26Z : No. of bitstreams: 1 pantaroto_s_me_botfca.pdf: 713863 bytes, checksum: b770073600a204323c2ead910c060f71 (MD5) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Durante o processamento de raízes de mandioca para a produção de farinha e fécula, são geradas grandes quantidades de resíduos, dentre os quais destacam-se a manipueira como água proveniente da prensa da massa de mandioca ralada para a produção de farinha ou água residual de fecularia, neste caso a manipueira diluída com água de extração. A linamarina é um b-glicosídeo de acetona cianidrina e etil-metil-cetona cianidrina, presente em todas as células da planta de mandioca. A clivagem deste glicosídeo, em decorrência da lise das paredes celulares da planta, dá início à cianogênese, ou seja, a produção de ácido cianídrico. A linamarina é solúvel em água, sendo carreada juntamente com os efluentes líquidos, gerando problemas tanto ambientais quanto econômicos, no que se refere à disposição final e aproveitamento dos mesmos como sub-produtos do processamento de mandioca. Na literatura há relatos sobre a habilidade de microrganismos a metabolizar a linamarina, como única fonte de carbono e energia. O presente estudo teve por objetivo o isolamento, seleção e identificação de microrganismos aeróbios, provenientes de amostras de manipueira e solo aos arredores de lagoas destinadas à decantação destes efluentes, avaliando-os quanto ao metabolismo de linamarina in vitro, visando o emprego das linhagens selecionadas em estudos futuros de biorremediação dos resíduos. Das amostras foram isoladas 118 culturas, das quais 66 caracterizaram-se como morfotipos bacterianos e 52 como leveduras. Dentre estes microrganismos, 31 morfotipos, sendo 26 bactérias e 5 por leveduras, escolhidos aleatoriamente, foram avaliados em meio mínimo contendo linamarina como única fonte de carbono e energia...( Resumo completo, clicar acesso eletrônico abaixo). / During the processing of cassava roots to produce flour and starch, residues are generated, where stand out the liquid effluents. The linamarin is a ß-glucoside of aceton cyanidrin and ethyl-methyl-ceton cyanidrin, it is present in all cassava plant. The cyanoglucoside broke begins the cyanogenese, thus producing cyanidric acid. The linamarin is soluble in water, and it is carried with the liquid effluents, and it generates ambiental and economics problems. The literature describe some microorganisms ability to metabolite linamarin. The present work aims the isolament, the selection and the identification of aerobies microorganisms from cassava liquid effluents and from adjacent soils samples of stabilization lagoons. Microbial cultures isolated have been available for linamarin in vitro metabolism. 118 strains are isolated, that 66 was characterized as bacteria and 52 as yeasts. 31 morfotypes were selected, choosed by chance, in minimum medium (MM), with linamarin as only carbon and energy source. Eight strains were selected ( seven bacterias and one yeast). The bacterias were identified by phylogenetic analyses, as three strains of Serratia marcescens, two strains of Bacillus, one strain of Acinetobacter johnnsonii, and one microbial culture of Proteobacteria group. The last one was not yet identified by literature. The yeast have been characterized by conventional taxonomy as Rhodotorulla glutinis...(Complete abstract, click electronic address below).

Orientador: Marney Pascoli Cereda / Resumo: Durante o processamento de raízes de mandioca para a produção de farinha e fécula, são geradas grandes quantidades de resíduos, dentre os quais destacam-se a manipueira como água proveniente da prensa da massa de mandioca ralada para a produção de farinha ou água residual de fecularia, neste caso a manipueira diluída com água de extração. A linamarina é um b-glicosídeo de acetona cianidrina e etil-metil-cetona cianidrina, presente em todas as células da planta de mandioca. A clivagem deste glicosídeo, em decorrência da lise das paredes celulares da planta, dá início à cianogênese, ou seja, a produção de ácido cianídrico. A linamarina é solúvel em água, sendo carreada juntamente com os efluentes líquidos, gerando problemas tanto ambientais quanto econômicos, no que se refere à disposição final e aproveitamento dos mesmos como sub-produtos do processamento de mandioca. Na literatura há relatos sobre a habilidade de microrganismos a metabolizar a linamarina, como única fonte de carbono e energia. O presente estudo teve por objetivo o isolamento, seleção e identificação de microrganismos aeróbios, provenientes de amostras de manipueira e solo aos arredores de lagoas destinadas à decantação destes efluentes, avaliando-os quanto ao metabolismo de linamarina "in vitro", visando o emprego das linhagens selecionadas em estudos futuros de biorremediação dos resíduos. Das amostras foram isoladas 118 culturas, das quais 66 caracterizaram-se como morfotipos bacterianos e 52 como leveduras. Dentre estes microrganismos, 31 morfotipos, sendo 26 bactérias e 5 por leveduras, escolhidos aleatoriamente, foram avaliados em meio mínimo contendo linamarina como única fonte de carbono e energia...( Resumo completo, clicar acesso eletrônico abaixo). / Abstract: During the processing of cassava roots to produce flour and starch, residues are generated, where stand out the liquid effluents. The linamarin is a ß-glucoside of aceton cyanidrin and ethyl-methyl-ceton cyanidrin, it is present in all cassava plant. The cyanoglucoside broke begins the cyanogenese, thus producing cyanidric acid. The linamarin is soluble in water, and it is carried with the liquid effluents, and it generates ambiental and economics problems. The literature describe some microorganisms ability to metabolite linamarin. The present work aims the isolament, the selection and the identification of aerobies microorganisms from cassava liquid effluents and from adjacent soils samples of stabilization lagoons. Microbial cultures isolated have been available for linamarin "in vitro" metabolism. 118 strains are isolated, that 66 was characterized as bacteria and 52 as yeasts. 31 morfotypes were selected, choosed by chance, in minimum medium (MM), with linamarin as only carbon and energy source. Eight strains were selected ( seven bacterias and one yeast). The bacterias were identified by phylogenetic analyses, as three strains of Serratia marcescens, two strains of Bacillus, one strain of Acinetobacter johnnsonii, and one microbial culture of Proteobacteria group. The last one was not yet identified by literature. The yeast have been characterized by conventional taxonomy as Rhodotorulla glutinis...(Complete abstract, click electronic address below). / Mestre

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