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  • 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.
41

Antitumor properties of kefir : possible bioactive component(s) and mechanism(s)

Chen, Chujian, 1966- January 2005 (has links)
No description available.
42

Avaliação da atividade de neutrófilos em ratos Wistar (Rattus norvegicus) tratados com quefir / Evaluation of the activity of neutrophils in Wistar rats (Rattus norvegicus) treated kefir

Zolini, Guilherme Pimenta de Padua 14 September 2006 (has links)
Made available in DSpace on 2016-05-02T13:55:25Z (GMT). No. of bitstreams: 1 Dissertacao Guilherme Zolini1.pdf: 7663 bytes, checksum: 2f28c5d53aef01e6521ccd46bac0339d (MD5) Previous issue date: 2006-09-14 / This work was carried out in the Microorganism Fisiology Biology and Phytopharmacy laboratories of the José do Rosário Vellano University (UNIFENAS) The aim of the study was to evaluate some aspects related to the immunitary activity of neutrophils in rats treated with kefir a probiotic made from various microorganisms The tests were conducted to determine the level of cytokine TNF-alpha cell recruiting cellular metabolism neutrophils oxygen consumption hydrogen peroxide formation by neutrophils screening for myeloperoxidase positive neutrophils and assay of redox titration The tested groups consisted of albino male Wistar rats the test group received 1,0 ml of kefir solution the negative control received 1,0 ml of saline solution (NaCl 0,9 %) and the positive control received 100 mg/kg of tocopherol (Vit E) except for those on TNF-alpha and cell recruiting in which the positive control received 0,5 mg/kg of dexamethasone by 7 days gavage except for redox assay where the groups did not consist of animals The results were analyzed by means +- SEM using comparison test of Student Newman Keuls (SNK) except for respirometry assay for which t Student test was used Significant differences were found in kefir and negative control groups in cell recruiting assays (P<0,05) hydrogen peroxide formation stimulated by forbol ester (P<0,05) and identification of myeloperoxidase (P<0,01) given that both previously mentioned had the same index shown by the positive control For the cell recruiting assay the kefir the positive control and the negative control groups presented 12,0 +- 1,0 x 106, 7,3 +- 1,4 x 106 and 17,2 +- 1,9 x 106 neutrophils/mL respectively On the other hand in the hydrogen peroxide formation stimulated by forbol ester the kefir and the positive control groups presented averages of 1,46 +- 0,16 e 1,50 +- 0,22 femtomol/cell respectively showing no difference The negative control at 2,14 +- 0,18 femtomol/cell was considered statistically different from the kefir group In the assay for myeloperoxidase identification kefir and positive control groups were considered identical with indexes of 54,8 +- 3,0 % 47,3 +- 5,7 % respectively different from the negative control group with index of 74,0 +- 1,9 % positive MPO The other assays did not show significant effects In conclusion the ingestion of kefir was capable of diminishing cell recruiting inhibiting H2O2 production and suggests the reduction of the activity of MPO in the neutrophils / Este trabalho foi realizado nos laboratórios de Fitofármacos e Biologia e Fisiologia de Microrganismos da Universidade José do Rosário Vellano (UNIFENAS) com objetivo de avaliar alguns aspectos relacionados à atividade imunitária de neutrófilos em ratos tratados com que fir um probiótico composto por vários microrganismos Os ensaios foram realizados para se determinar o nível da citocina TNF-alpha recrutamento celular metabolismo celular consumo de oxigênio pelos neutrófilos formação de peróxido de hidrogênio pelos neutrófilos pesquisa de neutrófilos mieloperoxidase positivos e ensaio de titulação redox Os grupos foram formados por ratos Wistar albinos machos onde o grupo teste recebeu 1,0 mL de solução de quefir controle negativo 1,0 mL de solução salina (NaCl 0,9%) e controle positivo recebeu tocoferol (vit E) na dose de 100 mg/kg; nos ensaios de dosagem de TNF-alpha e recrutamento celular, contudo o controle positivo recebeu dexametasona na dose de 0,5 mg/kg por gavagem durante 7 dias exceto em ensaio redox onde grupos não foram formados por animais Os dados obtidos foram analisados por médias +- EPM seguindo teste de comparação de Student Newman Keuls (SNK) exceto para ensaio de respirometria que foi feito teste t de Student Foram encontradas diferenças significativas entre os grupos quefir e controle negativo nos ensaios de recrutamento celular (P<0,05) formação de peróxido de hidrogênio estimulado com ester de forbol (P<0,05) e identificação da mieloperoxidase (P<0,01) observando que ambos anteriormente citados apresentaram índices iguais ao controle positivo Para o ensaio de recrutamento celular os grupos quefir controle positivo e controle negativo apresentaram 12,0 +- 1,0 x 106 7,3 +- 1,4 x 106 e 17,2 +- 1,9 x 106 neutrófilos/mL respectivamente Já no ensaio de formação de peróxido de hidrogênio estimulado com ester de forbol os grupos quefir e controle positivo apresentaram médias de 1,46 +- 0,16 e 1,50 +- 0,22 femtomol/cel respectivamente não evidenciando diferença o controle negativo apresentou valor de 2,14 +- 0,18 femtomol/cel sendo considerado estatisticamente diferente ao grupo quefir No ensaio de identificação da mieloperoxidase o grupo quefir e controle positivo foram considerados iguais com índices de 54,8 +- 3,0 % e 47,3 +- 5,7 % respectivamente e diferentes do grupo controle negativo com índice de 74,0 +- 1,9 % MPO positivo Os demais ensaios não apresentaram efeitos significativos Concluiu-se que a ingestão do quefir foi capaz de diminuir o recrutamento de neutrófilos inibir a produção de H2O2 e sugere a diminuição da atividade de MPO nos neutrófilos
43

Pieno ir kefyro mikrobiologinių rodiklių analizė / Milk and kefir microbiological analysis

Adamavičiūtė, Deimantė 16 March 2006 (has links)
The aim of this work is to research milk and kefir microbiological indicators according to microbiological risk factors in the milk processing company A. Work tasks: to analyze drinking milk, ultra high temperature pasteurized milk and kefir descriptions and factors of the risk in technological process schemes; microbiological factors of the risk control schemes; samples of these products microbiological indicators according to company’s self-control plan. Conclusion: The main microbiological risk factors in drinking milk is total bacterial count, coliform bacteria, Salmonella; in the kefir – coliform bacteria, yeasts and moulds. Principals control points in drinking milk, ultra high temperature pasteurized milk and kefir technological schemes are: reception of the raw cow’s milk; freezing of the raw cow’s milk, storage and keeping; pasteurization of milk and freezing, pasteurized milk compound storage and keeping; milk warming, deaeration, homogenization, sterilization and refreshing (only for ultra high temperature pasteurized milk); repeated thermal treatment, cooling up to inoculation temperature (only for kefir); inoculation and incubation (only for kefir); storage. In the company’s A self-control plan preview principal control points microbiological risk factors are controlled by keeping a check of heating and freezing stages temperature and duration, monitoring of microbiological parameters are made not less than 4 times per year. Coliform bacteria and total bacteria... [to full text]
44

Production of kepi grains using pure cultures as starters

Cronje, Marise Christine 03 1900 (has links)
Thesis (MSc Food Sc )--Stellenbosch University, 2003. / ENGLISH ABSTRACT: Kepi is a refreshing, fermented dairy beverage that differs from other fermented milk products in that it is produced with a mixed microbial community which is confined to discrete grains. These grains can be recovered as a solid matrix at the end of the fermentation and then be reutilised as a starter to ferment the next batch of milk. The grain microbial community consists of a symbiotic association of yeasts and lactic acid bacteria, but the overall composition of the grains has not been completely elucidated. The microbes in the grains are embedded in a protein-polysaccharide Kefiran matrix, which appears essential for grain formation. The mechanism of grain formation is still not fully understood and it thus remains undecided which organism is really responsible for the production of this proteinpolysaccharide matrix. The aim of this study was to isolate, characterise and identify the microbes present in Kefiran from mass cultured South African grains and then to evaluate grain formation with these purified cultures isolated from Kefiran strings using a mass cultivation process. Sixteen strains of lactic acid bacteria and one yeast strain were isolated from Kefiran strings produced during the mass cultivation of South African Kepi grains. API technology, numerical clustering and DNA sequence comparisons were used to identify the purified isolates. The isolates were grouped into seven clusters by numerical clustering and clustering distance from selected reference and marker strains. The heterofermentative lactobacilli were identified as Lactobacillus parakefiri and Lb. kefiri and the homofermentative strains as Lb. delbrueckii ssp. bulgaricus, Lb. gallina rum, Lb. acidophilus and Lb. bavaricus. One isolate was found to be a member of the genus Lactobacillus, but was not positively identified to species level. Cultures isolated from Kefiran were evaluated for ability to grain formation by adding 1 x 109 cfu.ml:' bacteria and 1 x 108 cfu.ml' yeast to double pasteurised, full cream milk during the mass cultivation process. It was found that the control and all the cultures in double pasteurised milk showed grain accumulation indicating that other microbes were present in pasteurised and double pasteurised milk which had an influence on the grain forming ability. The cultures isolated from pasteurised and double pasteurised milk included members of the species Pediococcus, Acinetobacter, Lactococcus laetis ssp. lactis, Candida lipolytica, C. guilliermondii, Chryseobacterium meningosepticum, Pseudomonas putida and four isolates of the Bacillus cereus group. It was found that these rod-shaped "milk isolates" resulted in grain accumulation when inoculated into UHT milk and it was concluded that the "milk isolates" did contribute to grain formation. These isolates were then combined with the Kefiran cultures and this resulted in grains very similar to the traditional Kepi grains. These grains were made from Lb. gallinarum in double pasteurised milk as well with a combination of Lb. gallinarum, Lb. acidophilus, Lb. kefiri, Lb. delbrueckii ssp. bulgaricus, Candida lambica and Pseudomonas putida in URT milk. The grains were firm, elastic and did not dissolve in water but kept their structure and were retained when sieved. An acceptable Kepi beverage was produced from these grains. From these typically traditional grain characteristics it was concluded that, even though the microbial compositions were probably not the same, the general appearance was similar to traditional grains and that it is thus possible to produce grains from pure single strain Kefiran cultures and "milk isolates". Furthermore, it was possible to produce a Kepilike beverage from these grains, which included similar characteristics as the traditional Kepi beverage. / AFRIKAANSE OPSOMMING: Kepi is "n verfrissende, gefermenteerde suiweldrankie wat van ander gefermenteerde produkte verskil in die opsig dat dit vervaardig word deur Kepi korrels in melk te inkubeer. Die Kepi korrels kan aan die einde van die fermentasie herwin word en weer gebruik word om die volgende lot melk te fermenteer. Die korrels bestaan uit "n simbiotiese samestelling van giste en melksuurbakterieë, maar die presiese samestelling van die korrels is steeds onbekend. Die mikro-organismes is vasgevang in "n proteïen-polisakkaried Kefiran matriks en die Kefiran word as essensieel beskou vir korrelvorming. Die meganisme van korrelvorming bly steeds onbekend en daar is nog nie tot "n gevolgtrekking gekom oor watter organisme die Kefiran produseerder is nie. Die doel van die studie was om die mikro-organismes in Kefiran te isoleer en te identifiseer deur Suid-Afrikaanse Kepi korrels te massa kweek. Hierdie mikroorganismes was dan verder geëvalueer ten opsigte van korrel vorming. Sestien melksuurbakterieë isolate en een gis isolaat is geïsoleer vanuit die Kefiran. API tegnologie, numeriese groepering en DNA volgorde vergelykings was gebruik om die isolate te identifiseer. Die isolate is in sewe groepe verdeel volgens numeriese groepering. Die afstand van verwysings en merker organismes is ook in ag geneem. Die heterofermentatiewe organismes is geïdentifiseer as Lactobacillus parakefiri en Lb. kefiri en die heterofermentatiewe organismes as Lb. delbrueckii ssp. bulgaricus, Lb. gallina rum, Lb. acidophilus en Lb. bavaricus. Een isolaat kon nie geïdentifiseer word tot op spesie vlak nie, maar is verwant aan die genus Lactobacillus. Hierdie geïsoleerde Kefiran kulture is geëvalueer ten op sigte van korrelvorming, deur 1 x 109 kve.ml' van die bakterieë en 1 x 108 kve.ml' van die gis by dubbel gepasteuriseerde volroom melk te voeg tydens die massakwekings proses. Die kontrole wat geen bygevoegde kulture bevat nie, sowel as die wat wel bygevoegde kulture bevat, het korrel vorming getoon. Laasgenoemde toon dat daar organismes teenwoordig is in gepasteuriseerde en dubbel gepasteuriseerde melk wat "n rol kan speel tydens korrelvorming. Die kulture wat geïsoleer is vanuit gepasteuriseerde en dubbel gepasteuriseerde melk, sluit in: Pediococcus, Acinetobacter, Lactococcus laetis ssp. lactis, Candida lipolytica, C. guilliennondii, Chryseobacterium menigosepticum, Pseudomonas putida en vier isolate van die Bacillus cereus groep. Hierdie organismes wat uit melk geïsoleer is, het korrelvorming getoon in UHT melk en die gevolgtrekking kan gemaak word dat die "melk organismes" wel "n rol speel tydens korrel vorming. Hierdie "melk isolate" in kombinasie met die Kefiran kulture het korrels tot gevolg gehad wat baie dieselfde was as tradisionele Kepi korrels. Laasgenoemde korrels is gemaak deur Lb. gallina rum in dubbel gepasteuriseerde melk, sowel as deur "n kombinasie van Lb. gallina rum, Lb. acidophilus, Lb. kefiri, Lb. delbrueckii ssp. bulgaricus, Candida lambica en Pseudomonas putida in UHT melk. Die korrels was stewig, elasties, het nie opgelos in water nie en het hulle struktuur behou wanneer gesif. Wanneer hierdie tipiese tradisionele korrels se eienskappe in ag geneem word, kan die gevolgtrekking gemaak word dat alhoewel die mikrobiese samestelling van die korrels nie dieselfde is as die tradisionele korrel nie, is die algemene voorkoms en eienskappe dieselfde en dat dit wel moontlik is om korrels te produseer deur isolate geïsoleer vanuit Kefiran en melk. Verder was dit moontlik om "n drankie te vervaardig met die korrels wat baie dieselfde is as tradisionele Kepi.
45

Produção do quefir com polpa de graviola (Annona muricata) e avaliação das características microbiológicas, fisico-químicas e de sua aceitabilidade

Contim, Luciana Silva Rocha 16 February 2007 (has links)
Submitted by Geyciane Santos (geyciane_thamires@hotmail.com) on 2015-09-04T10:30:51Z No. of bitstreams: 1 Dissertação - Luciana Silva Rocha Contim.pdf: 1273564 bytes, checksum: 087c9d4ee173aa13004dc6a712e6b6ee (MD5) / Approved for entry into archive by Divisão de Documentação/BC Biblioteca Central (ddbc@ufam.edu.br) on 2015-10-02T19:22:51Z (GMT) No. of bitstreams: 1 Dissertação - Luciana Silva Rocha Contim.pdf: 1273564 bytes, checksum: 087c9d4ee173aa13004dc6a712e6b6ee (MD5) / Approved for entry into archive by Divisão de Documentação/BC Biblioteca Central (ddbc@ufam.edu.br) on 2015-10-02T19:27:34Z (GMT) No. of bitstreams: 1 Dissertação - Luciana Silva Rocha Contim.pdf: 1273564 bytes, checksum: 087c9d4ee173aa13004dc6a712e6b6ee (MD5) / Made available in DSpace on 2015-10-02T19:27:34Z (GMT). No. of bitstreams: 1 Dissertação - Luciana Silva Rocha Contim.pdf: 1273564 bytes, checksum: 087c9d4ee173aa13004dc6a712e6b6ee (MD5) Previous issue date: 2007-02-16 / FAPEAM - Fundação de Amparo à Pesquisa do Estado do Amazonas / Kefir is a product of milk fermentation with kefir grains and cultures prepared from grains. In these grains (polysaccharide matrix), lactic bacteria and yeasts live in symbiosis and they perform alcoholic and lactic fermentation. Kefir is an old beverage originated from Caucasians Mountains. Many studies have investigated its nutritional and biotherapeutic benefits. Among its functional qualities it can be cited: relieve all intestinal disorders, antibacterial and antitumoral action, hypocholesterolemic action and others. Graviola is a well known and accepted fruit in the Amazon region. It has been produced almost through the year, which becomes easily available. Because of its qualities and searching utilization of amazon fruits, a kefir beverage was produced with graviola pulp. Its microbiological and physic-chemical characteristics were evaluated during the period of refrigerator, as well as its acceptability. Kefir was produced with 5% of grains as starter-cultures and the fermentation was divided in two stages: the first one at 25oC for 24 hours and the second one at 7oC for 24 hours. Two types of beverages were produced: a natural kefir (control) and a kefir with adde 15% of graviola pulp and 12% of sugar. These beverages were placed on glass jars with metal lid, previously sterilized and kept by refrigeration storage in commercial refrigerators at about 7oC temperature. The microbiological and physic-chemical analyses were carried out at 0, 7, 14, 21 and 28 days of storage. The acceptability test was made at 0 time of storage. The main groups of microorganisms presented in kefir were Lactobacillus, Lactococcus, yeast and acetic bacteria quantified in specific broth. The total number of microorganisms was similar for all groups, around 109 cfu/g. After 28 days of storage it was reduced to 107 cfu/g. It was verified that the addition of graviola pulp and sugar in natural kefir did not influence the behavior of its microbiota. Lactic bacterias were isolated from kefir grains and 9 bacteria were characterized as Lactococcus lactis subps. lactis. The pH did not vary significantly during 21 days of storage. The pH increased significantly with 28 days of storage under refrigeration. The acidity (% of acid lactic) increased gradually during the storage period. However, there was not significant interaction among the acidity values on natural kefir and kefir with graviola pulp. The sensorial analyzes of kefir with graviola pulp showed score acceptability from good to excellent. / Quefir é um produto obtido através da fermentação do leite com os grãos de quefir e de culturas preparadas a partir dos grãos. Nestes grãos, (matriz polissacarídica), bactérias láticas e leveduras vivem em simbiose e promovem dupla fermentação: lática e alcoólica. Apesar de pouco conhecida, o quefir é uma bebida bem antiga, originada das montanhas caucasianas. Muitos estudos têm investigado seu valor nutricional e bioterapêutico. Entre as suas qualidades funcionais podem ser citados: alívio de desordens intestinais, ação antibacteriana e anticarcinogênica, ação hipocolesterolêmica entre outras. A graviola é uma fruta bem aceita e conhecida na região amazônica sendo produzida em quase todo ano, facilitando com isto sua obtenção. Tendo em vista as qualidades do quefir e buscando o aproveitamento de frutos da região amazônica, foi produzida uma bebida de quefir com polpa de graviola e suas características microbiológicas, físico-químicas foram avaliadas durante o período de estocagem sob refrigeração assim como a sua aceitabilidade. O quefir foi produzido com 5% de grãos como inóculo e a fermentação foi dividida em duas etapas; a primeira a 25oC por 24 horas e a segunda a 7oC por 24 horas. Foram produzidos dois tipos de bebidas: quefir natural (controle) e o quefir com 15% de polpa de graviola e 12% de açúcar. As bebidas foram armazenadas, em recipientes de vidro com tampa rosqueáveis previamente esterilizados, sob refrigeração em geladeiras comerciais com temperatura aproximada de 7oC e as análises físico-quimicas e microbiológicas foram realizadas nos tempos 0, 7, 14, 21 e 28 dias de estocagem. O teste de aceitabilidade foi realizado no tempo zero de estocagem. Os principais grupos de microrganismos presentes no quefir: Lactobacillus, Lactococcus, leveduras e bactérias acéticas foram quantificados em meios de cultura específicos e o número observado foi similar para todos os grupos, em torno de 109 ufc/g e ao final de 28 dias de estocagem decaíram para cerca de 107 ufc/g. Verificou-se que a adição de polpa de fruta e açúcar ao quefir natural não influenciou no comportamento de sua microbiota analisada. Bactérias láticas foram isoladas dos grãos de quefir sendo os 9 isolados caracterizados como Lactococcus lactis subp. lactis. Os valores de pH não variaram significativamente durante 21 dias de estocagem, aumentado significativamente somente com 28 dias de estocagem sob refrigeração. A acidez (% de ácido lático) aumentou progressivamente durante o tempo de armazenagem não havendo, no entanto interação significativa entre os valores de acidez observados para o quefir natural e o quefir com polpa de graviola. Analise sensorial do quefir com polpa de graviola revelou uma aceitabilidade muito boa a excelente.

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