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Proteolytic activities of bacteria, yeasts and filamentous fungi isolated from coffee fruit (Coffea arabica L.)
Rodarte, Mirian Pereira;Dias, Disney Ribeiro;Vilela, Danielle Marques;Schwan, Rosane Freitas;
Acta Scientiarum. Agronomy , 2011, DOI: 10.4025/actasciagron.v33i3.6734
Abstract: one hundred forty-four microorganisms previously isolated from coffee fruit (coffea arabica) were grown on casein agar to evaluate their proteolytic activities. fifty percent of filamentous fungi, 52.5% of bacteria and 2.6% of yeasts were able to secrete proteases. positive isolates were further examined in liquid culture for their protease activities by hydrolysis of casein at different ph values (5.0, 7.0 and 9.0) at 30 o c. bacillus megaterium, b. subtilis, enterobacter agglomerans, kurthia sp, pseudomonas paucimobilis and tatumella ptyseos demonstrated the highest proteolytic activities at ph 9.0. one yeast isolate, citeromyces matritensis, had a proteolytic activity of 2.40 u at ph 5.0. aspergillus dimorphicus, a. ochraceus, fusarium moniliforme, f. solani, penicillium fellutanum and p. waksmanii showed the highest activities. of the bacterial isolates, the highest enzyme activities were observed in b. subtilis 333 (27.1 u), tatumella ptyseos (27.0 u) and b. megaterium 817 (26.2 u). of the filamentous fungi, aspergillus ochraceus (48.7 u), fusarium moniliforme 221 (37.5 u) and f. solani 359 (37.4 u) had the highest activities at ph 9.0.
Proteolytic activities of bacteria, yeasts and filamentous fungi isolated from coffee fruit (Coffea arabica L.) = Atividade proteolítica de bactérias, leveduras e fungos filamentosos presentes em gr os de café (Coffea arabica L.)
Mirian Pereira Rodarte,Disney Ribeiro Dias,Danielle Marques Vilela,Rosane Freitas Schwan
Acta Scientiarum : Agronomy , 2011,
Abstract: One hundred forty-four microorganisms previously isolated from coffee fruit (Coffea arabica) were grown on casein agar to evaluate their proteolytic activities. Fifty percent of filamentous fungi, 52.5% of bacteria and 2.6% of yeasts were able to secrete proteases. Positiveisolates were further examined in liquid culture for their protease activities by hydrolysis of casein at different pH values (5.0, 7.0 and 9.0) at 30 oC. Bacillus megaterium, B. subtilis, Enterobacteragglomerans, Kurthia sp, Pseudomonas paucimobilis and Tatumella ptyseos demonstrated the highest proteolytic activities at pH 9.0. One yeast isolate, Citeromyces matritensis, had a proteolytic activityof 2.40 U at pH 5.0. Aspergillus dimorphicus, A. ochraceus, Fusarium moniliforme, F. solani, Penicillium fellutanum and P. waksmanii showed the highest activities. Of the bacterial isolates, the highestenzyme activities were observed in B. subtilis 333 (27.1 U), Tatumella ptyseos (27.0 U) and B. megaterium 817 (26.2 U). Of the filamentous fungi, Aspergillus ochraceus (48.7 U), Fusarium moniliforme 221 (37.5 U) and F. solani 359 (37.4 U) had the highest activities at pH 9.0. Este trabalho teve por objetivos avaliar a capacidade de secre o de proteases extracelulares por 144 microrganismos, previamente isoladosde gr os de café (Coffea arabica) durante fermenta o por via seca, e determinar a atividade das enzimas produzidas. Os microrganismos foram cultivados em ágar-caseína para avalia o da produ o de enzimas proteolíticas. Dos 40 isolados de bactéria presentes na amostra, 52,5% apresentaram resultado positivo para o teste. Considerando os 66 isolados de fungos filamentosos, 50% foram capazes de secretar proteases, enquanto que dos 38 isolados de leveduras, apenas 2,6% conseguiram promover a hidrólise da caseína do meio. Os isolados que apresentaram capacidade de secre o de proteases foram, posteriormente, cultivados em meio líquido para a determina o da atividade enzimática em diferentes valores de pH (5,0, 7,0 e 9,0) a30 oC. Os isolados Aspergillus ochraceus (48,7 U), Fusarium moniliforme 221 (37,5 U) e F. solani 359 (37,4 U) apresentaram os melhores resultados de atividade enzimática, o que foi verificado empH 9,0. Também neste pH os isolados Bacillus subtilis 333 (27,1 U), Tatumella ptyseos (27,0 U) e B. megaterium 817 (26,2 U) apresentaram maior valor de atividade. A levedura Citeromyces matritensis apresentou atividade em pH 5,0 (2.40 U).
Caffeine content of Ethiopian Coffea arabica beans
Silvarolla, Maria Bernadete;Mazzafera, Paulo;Lima, Marinez Muraro Alves de;
Genetics and Molecular Biology , 2000, DOI: 10.1590/S1415-47572000000100036
Abstract: the coffee germplasm bank of the instituto agron?mico de campinas has many coffea arabica accessions from ethiopia, which is considered the primary center of genetic diversity in coffee plants. an evaluation of the caffeine content of beans from 99 progenies revealed intra- and inter-progeny variability. in 68 progenies from the kaffa region we found caffeine values in the range 0.46-2.82% (mean 1.18%), and in 22 progenies from illubabor region these values ranged from 0.42 to 2.90% (mean 1.10%). this variability could be exploited in a breeding program aimed at producing beans with low-caffeine content.
Caffeine content of Ethiopian Coffea arabica beans  [cached]
Silvarolla Maria Bernadete,Mazzafera Paulo,Lima Marinez Muraro Alves de
Genetics and Molecular Biology , 2000,
Abstract: The coffee germplasm bank of the Instituto Agron mico de Campinas has many Coffea arabica accessions from Ethiopia, which is considered the primary center of genetic diversity in coffee plants. An evaluation of the caffeine content of beans from 99 progenies revealed intra- and inter-progeny variability. In 68 progenies from the Kaffa region we found caffeine values in the range 0.46-2.82% (mean 1.18%), and in 22 progenies from Illubabor region these values ranged from 0.42 to 2.90% (mean 1.10%). This variability could be exploited in a breeding program aimed at producing beans with low-caffeine content.
Inibi o in vitro de fungos toxigênicos por Pichia sp. e Debaryomyces sp. isoladas de frutos de café (Coffea arabica) = In vitro inhibition of toxigenic filamentous fungi by Pichia sp. and Debaryomyces sp. isolates from coffee (Coffea arabica) fruits
Darlê Martins Barros Ramos,Cristina Ferreira Silva,Luís Roberto Batista,Rosane Freitas Schwan
Acta Scientiarum : Agronomy , 2010,
Abstract: O café é um produto nacional com grande express o para a economia brasileira. O uso excessivo de fungicidas tem levado a pesquisas sobre formas alternativas como o controle biológico. Objetivou-se avaliar o potencial antag nico de leveduras em co-cultivo com fungos filamentosos. Isolados das espécies Debaryomyces hansenii (UFLACF 889 e UFLACF 847) e Pichia anomala (UFLACF 710 e UFLACF 951) foram inoculados (103 a 106 células mL-1) com três espécies de fungos filamentosos, Aspergillus ochraceus, A. parasiticus e Penicillium roqueforti (103 a 106 esporos mL-1). A avalia o do crescimento micelial e a contagem de esporos foram realizadas durante 21 dias. Observou-se que o isolado UFLACF 889 apresentou, em média, maior efeito inibitório na produ o de esporos de A. ochraceus (inibi o de 82%) e P. roqueforti (74%). O isolado UFLACF 710 inibiu a produ o deesporos, em média, 60 e 75,6% de A. ochraceus e P. roqueforti, respectivamente. A. parasiticus foi o fungo mais resistente à inibi o pelas leveduras. O crescimento micelial n o foi inibido pela presen a da levedura em co-cultivo. Portanto, pode-se concluir que leveduras em cultivo pareado com fungos filamentosos s o capazes de inibir a produ o de esporos e, potencialmente, diminuir a dissemina o destes fungos no processamento de café. Coffee is a national product with great importance for the Brazilian economy. The excessive use of pesticides led to research for alternative forms, such as biological control. The objective of this work was to assess the potential antagonistic effect of yeast in dualculture with filamentous fungi. Isolates of Debaryomyces hansenii (UFLACF 889 and UFLACF 847) and Pichia anomala (UFLACF 710 and UFLACF 951) species were inoculated (103 to 106 células mL-1) with three species of filamentous fungi, Aspergillus ochraceus, A. parasiticus and Penicillium roqueforti (103 to 106 spores mL-1). The assessmentof mycelial growth and counting of spores was done for 21 days. It was observed that the isolated UFLA CF 889 attained, on average, the greatest inhibitory effect on the spore production of A. ochraceus (inhibition of 82%) and P. roqueforti (74%). The isolated UFLA CF 710 inhibited the spore production, on average, 60 and 75.6% of A. ochraceus and P. roqueforti, respectively. The fungus A. parasiticus was the most resistant to inhibition by yeasts. The mycelial growth was not inhibited by the presence of yeast in dual-culture. It could be concluded that yeast in dual-cultiure with filamentous fungi were able to inhibit the production of spores and potentially reduce the spread of
High-Throughput Metabolic Profiling of Diverse Green Coffea arabica Beans Identified Tryptophan as a Universal Discrimination Factor for Immature Beans  [PDF]
Daiki Setoyama, Keiko Iwasa, Harumichi Seta, Hiroaki Shimizu, Yoshinori Fujimura, Daisuke Miura, Hiroyuki Wariishi, Chifumi Nagai, Koichi Nakahara
PLOS ONE , 2013, DOI: 10.1371/journal.pone.0070098
Abstract: The maturity of green coffee beans is the most influential determinant of the quality and flavor of the resultant coffee beverage. However, the chemical compounds that can be used to discriminate the maturity of the beans remain uncharacterized. We herein analyzed four distinct stages of maturity (immature, semi-mature, mature and overripe) of nine different varieties of green Coffea arabica beans hand-harvested from a single experimental field in Hawaii. After developing a high-throughput experimental system for sample preparation and liquid chromatography-mass spectrometry (LC-MS) measurement, we applied metabolic profiling, integrated with chemometric techniques, to explore the relationship between the metabolome and maturity of the sample in a non-biased way. For the multivariate statistical analyses, a partial least square (PLS) regression model was successfully created, which allowed us to accurately predict the maturity of the beans based on the metabolomic information. As a result, tryptophan was identified to be the best contributor to the regression model; the relative MS intensity of tryptophan was higher in immature beans than in those after the semi-mature stages in all arabica varieties investigated, demonstrating a universal discrimination factor for diverse arabica beans. Therefore, typtophan, either alone or together with other metabolites, may be utilized for traders as an assessment standard when purchasing qualified trading green arabica bean products. Furthermore, our results suggest that the tryptophan metabolism may be tightly linked to the development of coffee cherries and/or beans.
Equine poisoning by coffee husk (Coffea arabica L.)
Diego Jose Z Delfiol, Jose P Oliveira-Filho, Fernanda L Casalecchi, Thatiane Kievitsbosch, Carlos A Hussni, Franklin Riet-Correa, Jo?o P Araujo-Jr, Alexandre S Borges
BMC Veterinary Research , 2012, DOI: 10.1186/1746-6148-8-4
Abstract: Six horses fed coast cross hay ad libitum were given access to coffee husks and excitability, restlessness, involuntary muscle tremors, chewing movements and constant tremors of the lips and tongue, excessive sweating and increased respiration and heart rates were the most evident clinical signs. Caffeine levels were measured in the plasma and urine of these horses on two occasions: immediately before the coffee husks were made available to the animals (T0) and at the time of the clinical presentation of intoxication, 56 h after the animals started to consume the husks (T56). The concentrations of caffeine in the plasma (p < 0.001) and urine (p < 0.001) of these animals were significantly greater at T56 than at T0.It was concluded that consumption of coffee husks was toxic to horses due to the high levels of caffeine present in their composition. Therefore, coffee husks pose a risk when used as bedding or as feed for horses.Brazil is the largest coffee producer in the world, and coffee grain processing generates a large amount of waste, given that close to 60% of the crude weight of the bean corresponds to the husk. The coffee (Coffea arabica) husk is rich in organic compounds and contains substances such as tannins, polyphenols and caffeine; the latter is often found in higher concentrations in the husk than in the bean [1]. Several studies have addressed reuse of the husks, especially as organic fertilizers, in tea production, caffeine extraction and the feeding of ruminants and pigs [2-6].Caffeine (C8H10N4O2) is a methylxanthine, which the most important effect is adenosine receptor antagonism [7]. Adenosine reduces spontaneous neuronal firing in multiple brain areas, and its presynaptic action inhibits neuronal release of acetylcholine, norepinephrine, dopamine, serotonin and gamma-aminobutyric acid; it produces sedation and has an anticonvulsant effect [8]. When caffeine binds to adenosine receptors, it prevents the inhibitory effects of adenosine [8], thereby
α-Amylase inhibitor-1 gene from Phaseolus vulgaris expressed in Coffea arabica plants inhibits α-amylases from the coffee berry borer pest
Aulus EAD Barbosa, érika VS Albuquerque, Maria CM Silva, Djair SL Souza, Osmundo B Oliveira-Neto, Arnubio Valencia, Thales L Rocha, Maria F Grossi-de-Sa
BMC Biotechnology , 2010, DOI: 10.1186/1472-6750-10-44
Abstract: We transformed C. arabica with the α-amylase inhibitor-1 gene (α-AI1) from the common bean, Phaseolus vulgaris, under control of the seed-specific phytohemagglutinin promoter (PHA-L). The presence of the α-AI1 gene in six regenerated transgenic T1 coffee plants was identified by PCR and Southern blotting. Immunoblotting and ELISA experiments using antibodies against α-AI1 inhibitor showed a maximum α-AI1 concentration of 0.29% in crude seed extracts. Inhibitory in vitro assays of the α-AI1 protein against H. hampei α-amylases in transgenic seed extracts showed up to 88% inhibition of enzyme activity.This is the first report showing the production of transgenic coffee plants with the biotechnological potential to control the coffee berry borer, the most important insect-pest of crop coffee.Coffee is one of the most valuable primary products in world trade, and its cultivation, processing, transportation and marketing provide employment for around 25 million people worldwide [1]. Furthermore, this culture is crucial to the economies of many developing countries, and its international trade reaches up to US$70 billion per year [2]. World coffee production is around 7 million metric tons, and Brazil is the leading producer [3].Coffea arabica is the main cultivated coffee species (70%) worldwide [4], and its production is commonly affected by different insect-pests. Among these pests, the most damaging is the coffee berry borer (CBB), Hypothenemus hampei (Ferrari, 1867) (Coleoptera: Curculionidae). CBB attacks and feeds on coffee berries, decreasing the quality and the flavour of the grain coffee and causing world-wide monetary losses of around US$500 million annually [5]. A major part of the insect life cycle is spent inside the coffee beans, making control very difficult [6]. Current methods used to control CBB are based on cultural, biological and predominantly chemical approaches. The use of the insecticide ENDOSULFAN is very widespread; however, CBB with high levels
Coffee (coffea arabica) pollination with africanized honeybees in venezuela
Manrique,Antonio José; Thimann,Rafael Ernesto;
Interciencia , 2002,
Abstract: in order to evaluate the pollination potential of africanized honeybees, 10 hives were placed between rows of a coffee (coffea arabica l.) plantation at "el laurel" experimental station, of the central university of venezuela, miranda state, venezuela. secondary branches were selected randomly from 60 adult plants. yields from uncovered (t1) and mesh covered (t2) branches, as well as from uncovered branches located 1km away from the hives (t3) were compared. number of flowers blooming per branch, mature grains per branch and weight of the wet/dry grains harvested were recorded. the numbers of mature grains relative to flowers showed differences (p<0.05) with percentages of 91.6 (t1), 82.6 (t2) and 86.9 (t3). differences (p<0.05) were found in wet weight (g/grain) with values of 2.05 (t1), 1.71 (t2) and 1.83 (t3). highly significant differences (p<0.01) were found for dry weight (g/grain) with values of 0.45 (t1), 0.37 (t2) and 0.41 (t3). the results suggest that the use of honeybees as coffee plant pollinators increases the percentage of mature grains/ branches; thus increasing yields.
Estimación temprana del potencial de rendimiento en café (Coffea arabica L.) Var. Bramón I Early estimation of potential yield in coffee (Coffea arabica L.) var. Bramón I
José Bustamante,Anabel Casanova,Román Numa,Carmen Monterrey
Bioagro , 2004,
Abstract: El mejoramiento genético del cafeto a través de estrategias tradicionales es un proceso lento debido a un período juvenil largo. También involucra altos presupuestos porque se requiere de la evaluación de un gran número de líneas y la selección de las más promisorias para lograr nuevas variedades estables en el tiempo. Con el presente estudio se pretende desarrollar un índice eficiente basado en el propuesto por Walyaro y Van Der Vossen, con el fin de seleccionar en edades tempranas de desarrollo plantas deseables con alto potencial de rendimiento. Se seleccionaron plantas individuales de 20 líneas de Coffea arabica, var. Bramón I, las cuales fueron estudiadas durante seis a os. Al segundo a o de edad se determinó el diámetro de la base del tallo y durante los cuatro últimos se evaluó la producción de café cereza por planta, estimándose en café oro por hectárea. Los resultados mostraron una correlación entre el diámetro de la base del tallo y la producción del segundo y tercer a o. Por tal motivo, estos parámetros pueden ser usados para predecir el potencial de rendimiento de líneas de café. Se desarrolló la siguiente ecuación que incluye el diámetro de la base del tallo y la producción del segundo y tercer a o: Y = 0,20 + 0,44 P2,3 + 0,60 (R2 = 0,91**). Este índice tuvo alta relación con la producción promedio de cuatro a os y puede permitir la selección de progenies promisorias cuando se pretende realizar una selección de alta intensidad en café. Genetic improvement in coffee by conventional breeding strategies is a slow process because of the long pre bearing period and also requires high budgets as it involves the evaluation of a large number of generations for obtaining stable varieties. Hence, the present study is aimed at developing an efficient selection index in coffee to select the desirable plants with consistent yield potential, in the early stages of plant life. Individual plants of 20 breeding lines of Coffea arabica var. Bramón I were selected, and at the second year of age the stem diameter at base was determined. Initial production of these plants was recorded for four consecutive years and evaluated the production of cherry beans per plant and estimated the yield of green coffee per hectare. The results showed that there was a correlation between the diameter of the stem base and clean coffee yield and hence this parameter could be indirectly used for predicting the yield potential of a line. An equation was formulated by including the diameter of the stem base and the production of second and third year (Y = 0.20 + 0.44 P2,3 + 0.60
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