Showing papers in "World Journal of Microbiology & Biotechnology in 1990"
TL;DR: Saccharomyces cerevisiae andZymomonas mobilis were grown on pineapple waste and their alcohol production characteristics compared and their caractéristiques de leur production d'alcool were compared.
Abstract: Saccharomyces cerevisiae andZymomonas mobilis were grown on pineapple waste and their alcohol production characteristics compared. The pineapple waste consisted of 19% cellulose, 22% hemi-cellulose, 5% lignin and 53% cell soluble matters but concentration of soluble sugars, which included 5.2% sucrose, 3.1% glucose and 3.4% fructose, was relatively low and pretreatment of the substrate was needed. Pretreatment of pineapple waste with cellulase and hemi-cellulase and then fermantation withS. cerevisiae orZ. mobilis produced about 8% ethanol from pineapple waste in 48 h.
79 citations
TL;DR: The present work reviews the numerous nitrile compounds that have been isolated from plants and animals to emphasize the potential use of different microorganisms for the detoxification of food and foodstuff.
Abstract: The present work reviews the numerous nitrile compounds that have been isolated from plants and animals. Two kinds of potentially toxic molecules are widespread, namely the cyanogenic glycosides and cyanollpids. Many other aromatic and allphatic nitriles are synthesized to a lesser extent. Different studies on the synthesis and degradation of these cyanogenic compounds are also reviewed to emphasize the potential use of different microorganisms for the detoxification of food and foodstuff.
77 citations
TL;DR: Although the limited break-down of the endosperm cell walls of sorghum may reflect sub-optimal activities of β-glucanases, such as endo-β-1,3:1,4- glucanase, it is possible that the highly intractable nature of the cell walls and their high protein content may contribute to the low susceptibility of Sorghum endos permits to enzymic degradation during malting.
Abstract: The endosperm cell walls of barley are degraded extensively during malting whilst those of sorghum are not. Malting barley produced endo-β-1,3:1,4-glucanase, endo-β-1,3-glucanase and pentosanase in large quantities. In contrast, malting sorghum developed mainly endo-β-1,3-glucanase and pentosanase. Although the limited break-down of the endosperm cell walls of sorghum may reflect sub-optimal activities of β-glucanases, such as endo-β-1,3:1,4-glucanases, it is possible that the highly intractable nature of the cell walls and their high protein content (approx. 60%) may contribute to the low susceptibility of sorghum endosperm cell walls to enzymic degradation during malting.
72 citations
TL;DR: Yeast cells that are viable contain an enzyme that decolourises methylene blue, whereas dead cells do not: dead cells are stained blue and living cells are unstained.
Abstract: Yeast cells that are viable contain an enzyme that decolourises methylene blue, whereas dead cells do not. When cells from a yeast sample are suspended in the dye, it penetrates into all the cells, but is reduced only by the living cells. It is very simple, therefore, to distinguish between living and dead cells by examining them microscopically: dead cells are stained blue and living cells are unstained.
60 citations
TL;DR: 2,3-Butanediol was produced at 12g/l (27% w/w yield) from the reducing sugars in wood hydrolysate byKlebsiella pneumoniae NRRL B-199 without changing ethanol production.
Abstract: 2,3-Butanediol was produced at 12g/l (27% w/w yield) from the reducing sugars in wood hydrolysate byKlebsiella pneumoniae NRRL B-199. Ethanol was present at 4 g/l and acetoin at 0.4 g/l. Optimum conditions for a 48 h fermentation were pH 6.0, 30°C and 50 g reducing sugars/l. Adding 1% (w/v) malt extract to the medium-enhanced butanedlol production to 13.3 g/l (yield 29%) without changing ethanol production.
52 citations
TL;DR: The results suggest a possible economic value of cassava peel in the production of fungal biomass and feedstock and the valorisation potentielle économique of pelures de manloc dans theproduction of biomasse and de substrat longique.
Abstract: Cassava peel was readily degraded and utilized by a strain ofRhizopus growing in a solid-state fermentation. Growth was maximal at 45°C and was proportional to the degree of hydrolysis of the peel. The yield of biomass, as weight of dry mycellum from the reducing sugars of the peel, was 51%. After 72 h fermentation, the peel contained 76% moisture, 6% cellulose, 7% hemicellulose and 0.4% ash and the protein content had increased from 5.6% to 16%. These results suggest a possible economic value of cassava peel in the production of fungal biomass and feedstock.
50 citations
TL;DR: There was 8-fold increase in biogas production from the spent straw compared with the original when used either in 3∶1 (w/w) or 1∶ 1 (w-w) combination with cattle dung.
Abstract: Rice straw, used as a substrate for three successive crops of the fruiting bodies ofPleurotus florida having 22% protein, had less cellulose but more nitrogen and ash than the original straw.In vitro digestibility using bacterial cellulase released 4.3-fold more reducing sugars per g cellulose from spent straw than from plain straw. There was 8-fold increase in biogas production from the spent straw compared with the original when used either in 3∶1 (w/w) or 1∶1 (w/w) combination with cattle dung.
47 citations
TL;DR: L Laboratory and field biodegradation studies showed both quantitative and qualitative changes in the hydrocarbon content of crude oil due to microbial degradative activities and a faster rate of oil depletion from the Lagos lagoon during the rainy season.
Abstract: The physico-chemical parameters of water samples collected from three points in the Lagos lagoon were studied for 12 months. Safinity varied seasonally but the temperature pH, dissolved O2, conductivity, NO3− and HPO42− concentrations were relatively constant. There was a direct proportionality between the population density of hydro-carbon-utilizing bacteria and the oil content of water samples. Twelve hydrocarbon-utilizing bacteria were isolated by selective enrichment and characterized as species ofPseudomonas, Alcaligenes, Acinetobacter andBacilius. The organisms grew mainly on long-chain aliphatic hydrocarbons. Laboratory and field biodegradation studies showed both quantitative and qualitative changes in the hydrocarbon content of crude oil due to microbial degradative activities and a faster rate of oil depletion from the Lagos lagoon during the rainy season. The results obtained could offer a predictive model for estimating the rate of disappearance of petroleum hydrocarbons from the tropical estuarine environment.
39 citations
TL;DR: Sweet potato residue, a starchy agricultural waste, was used as a substrate to produce oxytetracycline by Streptomyces rimosus TM-55 in a solid-state fermentation, and reached its maximum value on the sixth day and remained constant to the twentieth day.
Abstract: Sweet potato residue, a starchy agricultural waste, was used as a substrate to produce oxytetracycline byStreptomyces rimosus TM-55 in a solid-state fermentation. Oxytetracycline was detected on the third day, reached its maximum value on the sixth day and remained constant to the twentieth day. Optimal conditions for oxytetracycline production were an initial pH of 5.5 to 6.5, supplemented with 20% (w/v) defatted roasted peanut meal, as the sole nitrogen source, 1.0% (w/v) CaCO3 and 2.0% (w/v) MgSO4·7H2O, being incubated at 26 to 35°C for 6 to 7 days. Oxytetracycline reached 12.1 mg/g substrate.
39 citations
TL;DR: Ten predominant lactic acid bacterial isolates from traditionally fermented milk and four isolate from an industrially fermented milk, Lacto, together with 14 reference strains of Lactobacillus and three ofLactococcus were examined for 32 characteristics.
Abstract: Ten predominant lactic acid bacterial isolates from traditionally fermented milk and four isolates from an industrially fermented milk, Lacto, together with 14 reference strains ofLactobacillus and three ofLactococcus were examined for 32 characteristics. Data were analysed using the simple matching coefficient and clustering was by unweighted pair group average linkage. All the isolated from traditionally fermented milk belonged to the genusLactobacillus. Seven isolates could be identified as belonging toL. helveticus, L. plantarum, L. delbrueckii subsp.lactis, L. casei subsp.casei andL. casel subsp.pseudoplantarum. Three of the isolates could only be identified as either betabacteria or streptobacteria. The four isolates from Lacto were identified asLactococcus lactis. However, they could not be identified to subspecies level.
39 citations
TL;DR: The effect of cellulosic substrates on the production of extra-cellular cellulases and their cellulolytic activity in Chaetomium globosum has been studied in shake flask cultures.
Abstract: The effect of cellulosic substrates on the production of extra-cellular cellulases and their cellulolytic activity inChaetomium globosum has been studied in shake flask cultures. Production of endoglucanase, exoglucanase and filter paper cellulase was highest with pure cellulose whereas β-glucosidase was maximally induced by wheat straw. A suitable pretreatment for wheat straw was peracetic acid followed by NaOH and that of bagasse with NaOH for saccharification.
TL;DR: The growth ofRhizopus oligosporus on a model solid substrate consisting of cassava starch and other nutrients embedded in a kappa-carrageenan matrix was followed microscoplcally and a descriptive model for the growth of Rhizopus ollgosporUS on the model substrate was proposed.
Abstract: The growth ofRhizopus oligosporus on a model solid substrate consisting of cassava starch and other nutrients embedded in a kappa-carrageenan matrix was followed microscoplcally. There were two distinct growth phases: (1) germination of spores and development of mycellum to form a loose network over the whole substrate surface; (2) increase in the density of the mycellum. Although some penetrative hyphae were produced, the biomass was malnly restricted to the surface. Consequently, starch utilization was greatest near the surface. Based on these observations a descriptive model for the growth ofRhizopus ollgosporus on the model substrate was proposed. The five steps are: (1) release of glucoamylase by the mycelium; (2) diffusion of the glucoamylase to the starch; (3) hydrolysis of the starch by the glucoamylase, releasing glucose; (4) diffusion of glucose; (5) absorption of glucose by the mycellum at the surface to produce new blomass.
TL;DR: Two strains ofRhizopus rhizopodiformis that produced lipases in broth culture were isolated and glycerol and lecithin stimulated lipase production further and Maltose was the best carbon source and peptone the best nitrogen source for the production of lipases.
Abstract: Two strains ofRhizopus rhizopodiformis that produced lipases in broth culture were isolated. Maximum lipase production (23 U/ml) was obtained after 72 h culture. Both the crude lipases were stable at 50°C for 30 min and at 45°C for 24 h. Maltose was the best carbon source and peptone the best nitrogen source for the production of lipases. Only glycerol and lecithin stimulated lipase production further.
TL;DR: Inoculated plants had greater plant height, leaf number, stem girth, biomass, phosphate and Zn2+ content, and higher amounts of mycorrhizal spores, per cent root colonization and external hyphae, as measured by per cent soil aggregation.
Abstract: Efficient vesicular arbuscular mycorrhizal (VAM) fungi were screened and selected for a slow-growing forest tree species,Tamarindus indica L., important in tropical forestry. Seedlings were inoculated with 13 different VAM fungi, obtained from various sources around the world. Inoculated plants had greater plant height, leaf number, stem girth, biomass, phosphate and Zn2+ content. They also had higher amounts of mycorrhizal spores, per cent root colonization and external hyphae, as measured by per cent soil aggregation.Tamarindus indica seedlings responded best to inoculation withGigaspora margarita (ICRISAT) followed byGlomus fasciculatum.
TL;DR: The shape and the protein profile on SDS polyacrylamide gel electrophoretograms suggested that the group of these five isolates is clearly distinct and differs widely from all the type strains, belonging to various genera.
Abstract: Diazotrophs, especially of genusAzospirillum were readily isolated from roots of many plants using semi-solid nitrogen free malate medium (NFM). These isolates formed fine, white sub-surface pellicle in nitrogen-free malate medium within 24h, which gradually moved to the surface, and exhibited high acetylene reduction rates. Using selected cultural and biochemical tests, most of the isolates were identified asAzospirillum brasilense. Four isolates from Kallar grass root surface and one isolate fromAtriplex root interior formed phenotypically a homogenous group. It shared many characteristics with the species of genusAzospirillum except shape. All the biochemical tests performed, categorized them withA. brasilense. However, the shape and the protein profile on SDS polyacrylamide gel electrophoretograms suggested that the group of these five isolates is clearly distinct and differs widely from all the type strains, belonging to various genera.
TL;DR: Twenty-fiveBacillus isolates comprising eight species fromdaddawa, daddawansoya, oglrl, okplhe andugba (all Nigerian fermented plant proteins) all produced glutamic acid in varying concentrations when grown in a basal medium.
Abstract: Twenty-fiveBacillus isolates comprising eight species fromdaddawa, daddawansoya, oglrl, okplhe andugba (all Nigerian fermented plant proteins) all produced glutamic acid in varying concentrations when grown in a basal medium. Glutamic acid release during the course of termentation indaddawa showed a corresponding release pattern by the fermentingBacillus subtilis isolate in the basal medium.
TL;DR: Production of exocellular β-mannan- and xylan-degrading enzymes by eight wood rotting fungi was studied and β-Mannanosidase was not detected in any culture filltrate.
Abstract: Production of exocellular β-mannan- and xylan-degrading enzymes by eight wood rotting fungi was studied. Although all organisms excreted β-mannanase, endoxyfanase and acetylxylan esterase, production ofl-α-arabinosidase and 4-O-methylglucuronidase was variable. β-Mannanosidase was not detected in any culture filltrate. Righest β-mannanase and endoxylanase activities were observed in cultures ofPolyporus versicolor andSchizophyllum commune grown in Avicel-supplemented media. While crude β-mannanases fromLinzites saepiria andS. commune exhibited equivalent affinities for gluco- and galactomannan substrates,P. versicolor β-mannanase preferred a glucomannan substrate and did not use galactomannan from guar sum as a substrate.
TL;DR: Adding glucose and NH4H2PO4 improved decolorization by the fungus (leaving 19% of original colour) and reduced the BOD5 and COD of the effluent after 48 h of incubation.
Abstract: Pulp and paper mill effluent was decolorized by growth ofAspergillus niger. Adding glucose (2.0 g/l) and NH4H2PO4 (1.0 g/l) improved decolorization by the fungus (leaving 19% of original colour) and reduced the BOD5 (43%) and the COD (41%) of the effluent after 48 h of incubation.
TL;DR: Klebsiella predominated amongst the 16 coliform species that were differentiated and resistance to ampicillin, tetracycline, and chloramphenicol was particularly high.
Abstract: The mean count of coliforms/ml in urban and hospital drains were 68.9×104 and 48.4×104, respectively.Klebsiella predominated amongst the 16 coliform species that were differentiated;Escherichia coli occurred with highest frequency. All the isolates were resistant to at least one antibiotic and resistance to ampicillin, tetracycline, and chloramphenicol was particularly high. Multiple antibiotic resistant strains were common in both environments—85% and 65% for hospital and urban sources, respectively. The difference in the frequency of resistant strains from the two sources was not significant. 20% of strains from the two sources were multiply resistant to six antibiotics. The role of untreated wastewater in the maintenance and dissemination of resistant coliforms and its public health significance are highlighted.
TL;DR: Amylase activity increased during the fermentation of fluted pumpkin seeds forogiri production with corresponding decreases in amounts of total carbohydrates and soluble sugars and protease also increased in activity during the termentation, giving higher amounts of free amino acids and a concomitant decrease in the total nitrogen of the seeds.
Abstract: Amylase activity increased during the fermentation of fluted pumpkin seeds forogiri production with corresponding decreases in amounts of total carbohydrates and soluble sugars. Sugars present were glucose, fructose, sucrose and an unidentified one. Protease also increased in activity during the termentation, giving higher amounts of free amino acids and a concomitant decrease in the total nitrogen of the seeds. Lipase activity was, however, minimal in the fermenting seeds.
TL;DR: Strains metabolizing toluene through anortho cleavage pathway were selected from the wild typemeta strain to obtain a fast-growing strain with doubling time reduced from 14 to 1.2 h and double-blocked and muconate-permeable mutants were also selected to reduce reversion frequency and to enhance muconic acid production.
Abstract: Pseudomonas sp strains, isolated from soil, utilized toluene as their sole carbon source through ameta cleavage pathway Strains metabolizing toluene through anortho cleavage pathway were selected from the wild typemeta strain Theortho pathway strains were subjected to chemostat selection to obtain a fast-growing strain with doubling time reduced from 14 to 12 h Benzoale and antibiotics enrichment selection procedures were utilized to select a blocked mutant The blocked mutant grew on acetate as its sole carbon source and oxidatively converted toluene tocis, cis-muconic acid Double-blocked and muconate-permeable mutants were also selected to reduce reversion frequency and to enhance muconic acid production In shake-flask experiments, muconic acid at 35 g/l was obtained after 2 days of fermentation In a 14 l fermenter, muconic acid was produced at 45 g/l in 4 days of controlled fed-batch fermentation The oxidative bioconversion process was also demonstrated in a 1500 l fermenter
TL;DR: Rhizobium meliloti-alfalfa (Medicago sativa) symbiosis was influenced by the rhizospheric application of naringenin which increased nodule number, nodule weight and nitrogenase activity.
Abstract: Rhizobium meliloti-alfalfa (Medicago sativa) symbiosis was influenced by the rhizospheric application of naringenin which increased nodule number, nodule weight (2-to 8-fold) and nitrogenase activity. Plant blomass and total nitrogen content also increased by 60 to 72%. The enhancing effects of naringenin were more pronounced if it was applied at the early vegetative stage of plant growth or at the time of sowing.
TL;DR: The mechanism of copper resistance, which is not yet clearly understood, though the copper resistance conferred by a plasmid pPT23D has been elucidated at the molecular level, is discussed.
Abstract: Naturally occurring, copper-resistant microorganisms are common in the environment. This review discusses the mechanism of copper resistance, which is not yet clearly understood, though the copper resistance conferred by a plasmid pPT23D has been elucidated at the molecular level. The different applications of copper-resistant microorganisms are described, including commerical bloleaching of copper ores. The construction of novel bioleaching strains through recombinant DNA technology may be possible. Biosorbents, the non-living microbial blomass, have been successfully used for metal recovery operations and are also reviewed.
TL;DR: Chemical pre-treatment enhanced saccharification of agricultural lignocellulosic residues using Aspergillus niger cellulase by between 16 and 38% and maximum saccharisation of alkali-treated bagasse was with 0.5% substrate over 48 h using 0.3 U enzyme/ml.
Abstract: Chemical pre-treatment enhanced saccharification of agricultural lignocellulosic residues usingAspergillus niger cellulase by between 16 and 38%. Maximum saccharification (76%) of alkali-treated bagasse was with 0.5% substrate over 48 h using 0.3 U enzyme/ml.
TL;DR: Two isolates, M1 and S128, were found which were highly toxic to both Aedes andCulex strains and were taxonomically classilled asBacllus thuringlensis H-14, standard of référence IPS-82.
Abstract: Screening for spore-forming bacteria to use against dipterous insects, namelyMusca domestica, Aedes aegypti andCulex pipiens from Egypt, led to two isolates, M1 and S128, being found which were highly toxic to bothAedes andCulex strains. They had calculated international Toxicity Units (ITU) valdes of 17,467 and 20,065 ITU/mg, respectively, as compared with 15,000 ITU/mg forBacillus thuringlensis H-14 IPS-82 Reference Standard. They were taxonomically classilled asBacllus thuringlensis H-14. Their sensitivity to a number ofBacillus phages is also described.
TL;DR: The amylolytic enzyme production byRhizopus oryzae NRRL 395 grown on different agricultural commodities was datermined to produce much higher enzyme activity from barley, corn, bats, and rice than from cassava.
Abstract: The amylolytic enzyme production byRhizopus oryzae NRRL 395 grown on different agricultural commodities was datermined. The mould produced much higher enzyme activity from barley, corn, bats, and rice than from cassava. The optimal temperature for enzyme production was 30°C. Neutralization with CaCO3 greatly enhanced the rate of enzyme production. Nitrogen supplementation of cassava resulted in higher enzyme yields.
TL;DR: Hydrolysis of three varieties of unmalted sorghum by endogenous amylases produced sufficient maltose and glucose for subsequent brewing of beer as well as optimal temperature and pH varied between the three varleties.
Abstract: Hydrolysis of three varieties of unmalted sorghum by endogenous amylases produced sufficient maltose and glucose for subsequent brewing of beer. The optimal temperature and pH of the sorghum amylase activities varied between the three varleties. β-Amylase was optimal when used at 60°C and pH 5 for two varieties but at 60°C and pH 6 for another. The optimal α-amylase activity was between about 72°C and 75°C for all the sorghum varieties. The activities of the amylases differed considerably between the species.
TL;DR: The influence of different organic and inorganic nitrogen source combinations and C∶N ratios was studied in connection with growth and protein production of Bacillus thuringiensis var.israelensis to find that organic nitrogen source could be partially replaced by (NH4)2SO4 with a significant increase in delta-endotoxin production.
Abstract: The influence of different organic and inorganic nitrogen source combinations and C∶N ratios was studied in connection with growth and protein production ofBacillus thuringiensis var.israelensis. Protein production was assumed to be proportional to delta-endotoxin production. Delta-endotoxin concentration increased when media were supplemented with (NH4)2SO4, but the delta-endotoxin: biomass dry weight ratio was unaffected by different C∶N ratios. Organic nitrogen source, yeast extract, could be partially replaced by (NH4)2SO4 with a significant increase in delta-endotoxin production.
TL;DR: Biodegradation of pure cellulose powder, bagasse and wheatstraw by five cellulolytic fungi, aspergillus niger, Chaetomium globosum, Scopulariopsis brevicaulis, Trichoderma koningii and Trichothecium roseum, was studied in solid culture conditions.
Abstract: Biodegradation of pure cellulose powder, bagasse and wheatstraw by five cellulolytic fungi,Aspergillus niger, Chaetomium globosum, Scopulariopsis brevicaulis, Trichoderma koningii andTrichothecium roseum, was studied in solid culture conditions. Minimum degradation was with pure cellulose. Bagasse and wheatstraw were the most suitable for growth and activity of cellulolytic fungi. All fungi contained cellulase activity.
TL;DR: During the fermentation of maize grains, the temperature and moisture increased and the pH decreased, with glutamic acid being the most abundant amino acid, but he protein content of the ‘masa’ increased during fermentation.
Abstract: Microorganisms associated with fermentation ofmasa wereLactobacillus plantarum, Pediococcus acidilactici, Lactobacillus fermentum andSaccharomyces cerevisiae. During the fermentation of maize grains, the temperature and moisture increased and the pH decreased. Most amino acids decreased in concentration during fermentation, with glutamic acid being the most abundant amino acid, but he protein content of the ‘masa’ increased during fermentation. The bacteria played the major role in the fermentation.