Production of a biosurfactant exhibiting excellent emulsification and surface active properties bySerratia marcescens

A biosurfactant exhibiting excellent emulsification activity and surface properties was isolated during growth ofSerratia marcescens on 2% (w/v) sucrose. Reduction in surface tension values and increase in the yield of biosurfactant during the late log phase of growth indicates that the biosurfactant is a secondary microbial metabolite. The biosurfactant formed stable emulsions with a wide variety of hydrocarbons. The isolated surface-active compound has a potential application in enhanced oil recovery and is stable over a wide range of temperatures (10-120‡C) and pH (2-12). This is the first report of effective and stable emulsion formation by a strain ofSerratia marcescens.     

Degradation of lignin and lignin related compounds by protoplasts isolated from Fomes annosus

Protoplasts from a lignolytic fungus Fomes annosus were prepared through enzymatic hydrolysis of mycelium utilizing Novozym, a wall lytic enzyme preparation. Isolated protoplasts and living mycelium were compared in their ability to degrade ¹⁴C-labelled lignin related phenols and dehydropolymers of labelled coniferyl alcohol (synthetic lignin). The amounts of ¹⁴CO₂ released from O¹⁴CH₃-groups, ¹⁴C-2-side chains and ¹⁴C-rings by protoplasts was in the same range as those for intact mycelium. The methoxyl groups of synthetic lignin were more rapidly metabolized by protoplasts than by mycelium. When calculated in dpm of released ¹⁴CO₂ per mg protein the decomposition of ¹⁴C-labelled synthetic lignin and lignin-related monomers in a hyphae-free system of protoplasts was considerable higher than that obtained by the intact mycelium. The presence of intact hyphae is thus not necessary for lignin degradation to occur.Non-common-abbreviations used DHP Dehydropolymer of coniferyl alcohol - LS lignosulfonates prepared from DHP     

Degradation of reactive dyes by ozonation and oxalic acid-assimilating bacteria isolated from soil

Ozonation and treatment of wastewaters with oxalic acid-assimilating bacterium was attempted for the complete degradation of reactive dyes. Oxalic acid-assimilating bacterium, Pandoraea sp. strain EBR-01, was newly isolated from soil under bamboo grove and was identified to be a member of the genus Pandoraea by physicochemical and biochemical tests including 16S rDNA sequence analysis. The bacterium was grown optimally at pH 7 and temperature of 30 degrees C under the laboratory conditions. Reactive Red 120 (RR120), Reactive Green 19 (RG19), Reactive Black 5 (RB5) and Remazol Brilliant Blue R (RBBR) were used in degradation experiments. At the initial reactive dye concentrations of 500 mg/l and the ozonation time of 80 min, it was confirmed that 75-90 mg/l oxalic acid was generated from reactive dyes by ozonation. Microbial treatment using EBR-01 greatly decreased the amount of oxalic acid in the mixture after 48 h, but it was not removed completely. TOC/TOC(0) of reactive dye solutions was also decreased to 80-90% and 20-40% by ozonation and microbial treatment using EBR-01, respectively. The study confirmed that consecutive treatments by ozone and microorganisms are efficient methods to mineralize reactive dyes.     

Degradation of parathion by Penicillium waksmani zaleski isolated from flooded acid sulphate soil

By enrichment culture technique, a fungus Penicillium waksmani Zaleski which can degrade parathion was isolated from an acid sulphate soil under flooded condition. The fungus tolerated parathion at concentrations as high as 1000 ppm. Initially, medium containing parathion supported less growth but at later stages the growth was equal to that of control treatment. Parathion was converted to aminoparathion by the fungus. The increase in the radioactivity in the aqueous phase of the culture filtrate after solvent extraction indicated the formation of certain polar metabolites.     

Human monoamine oxidase enzyme inhibition by coffee and beta-carbolines norharman and harman isolated from coffee

Monoamine oxidase (MAO) is a mitochondrial outer-membrane flavoenzyme involved in brain and peripheral oxidative catabolism of neurotransmitters and xenobiotic amines, including neurotoxic amines, and a well-known target for antidepressant and neuroprotective drugs. Recent epidemiological studies have consistently shown that coffee drinkers have an apparently lower incidence of Parkinson's disease (PD), suggesting that coffee might somehow act as a purported neuroprotectant. In this paper, "ready to drink" coffee brews exhibited inhibitory properties on recombinant human MAO A and B isozymes catalyzing the oxidative deamination of kynuramine, suggesting that coffee contains compounds acting as MAO inhibitors. MAO inhibition was reversible and competitive for MAO A and MAO B. Subsequently, the pyrido-indole (beta-carboline) alkaloids, norharman and harman, were identified and isolated from MAO-inhibiting coffee, and were good inhibitors on MAO A (harman and norharman) and MAO B (norharman) isozymes. beta-carbolines isolated from ready-to-drink coffee were competitive and reversible inhibitors and appeared up to 210 microg/L, confirming that coffee is the most important exogenous source of these alkaloids in addition to cigarette smoking. Inhibition of MAO enzymes by coffee and the presence of MAO inhibitors that are also neuroactive, such as beta-carbolines and eventually others, might play a role in the neuroactive actions including a purported neuroprotection associated with coffee consumption.     

Phycicoccus ochangensis sp. nov., isolated from soil of a potato cultivation field

Two novel, Gram-positive, motile, coccal bacteria, strains L1b-b9^T and B5a-b5, were isolated from a potato cultivation field in Ochang, Korea. These isolates grew at 10–45°C, pH 5.0–10.0, and in the presence of 8% (w/v) NaCl. The diagnostic diamino acid in the cell-wall peptidoglycan was meso-diaminopimelic acid. The major menaquinone was MK-8(H₄) and the main cellular fatty acids were iso-C_14:0, iso-C_15:0, and anteiso-C_15:0. Polar lipids in strain L1b-b9^T consisted of diphosphatidylglycerol, phosphatidylglycerol, phosphatidylinositol, and an unknown glyco-amino lipid. The G+C content of genomic DNA was 73.6 mol%. A phylogenetic analysis based on 16S rRNA gene sequences showed that strains L1b-b9^T and B5a-b5 shared 99.36% similarity and formed a robust clade with the type species of the genus Phycicoccus. Strain L1b-b9^T is related most closely to Phycicoccus cremeus V2M29^T (97.52% 16S rRNA gene sequence similarity). On the basis of phylogenetic characteristics, the name Phycicoccus ochangensis sp. nov. is proposed for strain LIb-b9^T (=KCTC 19694^T =JCM 17595^T).     

Phlebotomine sandflies and leishmaniasis risks in Colombian coffee plantations under two systems of cultivation

The phlebotomine sandfly fauna of traditional (shaded) and intensified (unshaded) coffee plantations in Colombia was sampled by a variety of methods and the species composition and density under the two systems compared. Twenty species of Lutzomyia sandflies (Diptera: Psychodidae: Phlebotominae) were collected, of which eight were found only in the 'Coffee Axis' ('Eje Cafetero') of the departments of Caldas, Risaralda and Quindio, six were exclusive to the department of Norte de Santander and six occurred in both regions. Four species were collected only in traditional plantations and two exclusively in intensified ones. At least 13 species occurred in both plantation types. Fifteen species are opportunistic man-biters and eight are suspected vectors of leishmaniasis caused by Le. braziliensis, Le. panamensis or Le. mexicana. Seven species were collected inside houses and may be involved in intradomiciliary transmission of Leishmania. The dominant species in Norte de Santander was Lu. spinicrassa, which made up 93.8% of all the sandflies collected in this department. This species was absent from the Eje Cafetero and a number of others among the 15 recorded there might be responsible for Leishmania transmission in this region, including Lu. trapidoi, Lu. yuilli, Lu. gomezi, L. hartmanni and Lu. ovallesi. Sandfly population densities were significantly higher in traditional plantations than in intensified ones. Residents of traditional plantations were able to describe sandflies in significantly more detail than those of intensified plantations, based on seven basic characteristics related to the appearance and biting behaviour of the insects.     

Metabolic and exercise endurance effects of coffee and caffeine ingestion

Caffeine (Caf) ingestion increases plasmaepinephrine (Epi) and exercise endurance; these results are frequentlytransferred to coffee (Cof) consumption. We examined theimpact of ingestion of the same dose of Caf in Cof or in water. Ninehealthy, fit, young adults performed five trials after ingesting(double blind) either a capsule (Caf or placebo) with water or Cof(decaffeinated Cof, decaffeinated with Caf added, or regularCof). In all three Caf trials, the Caf dose was 4.45 mg/kgbody wt and the volume of liquid was 7.15 ml/kg. After 1 h of rest, thesubject ran at 85% of maximal O₂consumption until voluntary exhaustion (~32 min in the placebo anddecaffeinated Cof tests). In the three Caf trials, the plasma Caf andparaxanthine concentrations were very similar. After 1 h of rest, theplasma Epi was increased (P < 0.05)by Caf ingestion, but the increase was greater(P < 0.05) with Caf capsules thanwith Cof. During the exercise there were no differences in Epi amongthe three Caf trials, and the Epi values were all greater(P < 0.05) than in the othertests. Endurance was only increased(P < 0.05) in the Caf capsule trial; there were no differences among the other four tests. One cannot extrapolate the effects of Caf to Cof; there must be a component(s) ofCof that moderates the actions of Caf.

     

Anaerobic filter treatment of wastewater from mushroom cultivation on coffee pulp

Wastewater from the pre-treatment of coffee pulp for mushroom cultivation was treated in an anaerobic filter reactor at laboratory scale. The digester was fed semicontinuously with 300 to 500 ml of fresh medium per day. Organic loading rates (OLR) applied ranged widely during the study, from 0.48 to 62.93 g chemical oxygen demand (COD)/1 d. Treating wastewater from the pasteurization of pulp, the highest strength studied, a COD removal efficiency of up to 87% was attained at a high OLR of 42.868 g COD/I d; while a high biogas production rate (BPR) of 2.89 I/I d was also achieved. However, the average organic matter removal efficiency was 53% at an OLR of 23.921 g COD/1 d, which indicates that process efficiency should be improved to achieve a good quality effluent. BPR averaged 1.72 1/1 d, which shows that with technical-scale reactors, high biogas production could be obtained for further use in the pasteurizing process itself (energy recycling).     

Degradation of polyisoprene rubber by newly isolated bacillus sp. AF-666 from soil

Various microorganisms were screened for their ability to degrade polyisoprene rubber (natural rubber latex gloves). Strain AF-666, newly isolated from a soil sample, was selected as the best strain having the ability to grow on polyisoprene containing plates. The strain identified as Bacillus sp. AF-666, was found to degrade polyisoprene rubber, both on basal agar plates (latex overlay) as well as in liquid medium. Qualitative analysis of degradation was done through scanning electron microscopy (SEM) and Fourier transform infrared (FTIR) spectroscopy. SEM showed changes in surface morphology, like appearance of pits and cracks, and marked difference in transmittance spectra of test and control due to changes in the functional groups, was detected through FTIR. CO₂ evolution as a result of rubber degradation, was calculated gravimetrically by Sturm Test. About 4.43 g/1 of CO₂ was produced in case of test, whereas, 1.57 g/1 in case of control. The viable number of cells (CFU/ml) was also higher in test than in control. Present study may provide an opportunity for further studies on the applications of biotechnological processes as a tool for rubber waste management.     

Degradation of chlorinated hydrocarbons by Clostridium sp. isolated from lindane-amended,flooded soil

Summary A Clostridium sp., isolated from flooded soil amended with lindane (γ-BHC), decomposed methoxychlor, γ-BHC and heptachlor in that order under anaerobic condition. During the bacterial degradation of ring-labelled C¹⁴-γ-BHC, there was a net loss of radioactivity from the reaction mixture. Release of C¹⁴O₂ during the degradation of C¹⁴-γ-BHC was negligible. Methane was not detected as an end product of γ-BHC breakdown. re]19720406     

Degradation of polyisoprene rubber by newly isolated Bacillus sp. AF-666 from soil

Various microorganisms were screened for their ability to degrade polyisoprene rubber (natural rubber latex gloves). Strain AF-666, newly isolated from a soil sample, was selected as the best strain having the ability to grow on polyisoprene containing plates. The strain identified as Bacillus sp. AF-666, was found to degrade polyisoprene rubber, both on basal agar plates (latex overlay) as well as in liquid medium. Qualitative analysis of degradation was done through scanning electron microscopy (SEM) and Fourier transform infrared (FTIR) spectroscopy SEM showed changes in surface morphology, like appearance of pits and cracks, and marked difference in transmittance spectra of test and control due to changes in the functional groups, was detected through FTIR. CO2 evolution as a result of rubber degradation, was calculated gravimetrically by Sturm Test. About 4.43 g/1 of CO2 was produced in case of test, whereas, 1.57 g/1 in case of control. The viable number of cells (CFU/ml) was also higher in test than in control. Present study may provide an opportunity for further studies on the applications of biotechnological processes as a tool for rubber waste management.     

Metal-free cultivation of Glomus sp. BEG 140 isolated from Mn-contaminated soil reduces tolerance to Mn

The ability of arbuscular mycorrhizal (AM) fungi of different origin and cultivation history to tolerate excessive levels of manganese (Mn) was studied using hydroponic sand culture. Maize plants were colonised with two lineages of Glomus sp. BEG 140 from Mn-contaminated soil kept for 2 years in metal-free substrate or in the original soil. For comparison, the plants were also inoculated with Glomus intraradices BEG 75 from uncontaminated soil or were left uncolonised. Manganese stress was simulated by irrigation with nutrient solutions containing Mn at high concentrations (0.1, 0.5 and 1 mM); control plants were supplied with 3.8 microM Mn. Whereas the growth of maize plants was not suppressed by Mn at the concentrations examined, the development of AM fungi was negatively influenced by the higher Mn concentrations, with significant differences between isolates and cultivation lineages. The isolate Glomus sp. from Mn-contaminated soil showed higher tolerance to Mn than G. intraradices from uncontaminated soil. Colonisation by G. intraradices was reduced by almost 90% when irrigated with 1 mM Mn, whereas colonisation by the Glomus sp. lineage kept in contaminated soil still reached high levels (65% of the colonisation level of the control plants). The lineage of Glomus sp. cultured in inert metal-free substrate tolerated excessive Mn levels to a lesser extent than the lineage kept long-term in the original contaminated soil, but withstood Mn at higher concentrations than the G. intraradices from uncontaminated soil.     

Role of caffeine and tannin in anti-toxigenic properties of coffee and tea

Aflatoxins B₁, B₂, G₁ and G₂ produced by Aspergillus parasiticus var. globosus IMI 120920 in detannin-caffeinated coffee and black tea were five times more concentrated than in normal tea and coffee. Extracts of normal coffee and tea powders significantly reduced aflatoxins production in liquid broth at 1 and 3 % concentrations, with tea extract. having a more pronounced effect than coffee extract Relevant anti-aflatoxigenic properties appear to be due to tannin and caffeine. These induced 95 % inhibition in aflatoxins at 0.3 % and 0.6 %, respectively. Roasting of contaminated coffee beans at 200 °C for 20 min is effective in the reduction of aflatoxins.     

Uptake of radiolabelled ochratoxin A from soil by coffee plants

[3H, 14C] Ochratoxin A, prepared biosynthetically, was applied in dilute NaHCO3 solution to the soil in which coffee plants had grown to four pairs of leaves. Three weeks later the compound, isolated from dilute NaHCO3 extract of leaves by immunoaffinity chromatography, was detected by scintillation counting as a 1-2 ppm component of leaf dry weight, greatly exceeding the trace (ppb) occurrence of ochratoxin A in some green coffees, which therefore might arise in the field directly from fungal activity in soil rather than from fungal infection of cherries or processed green coffee.     

Degradation of the phenoxy acid herbicide diclofop-methyl by Sphingomonas paucimobilis isolated from a Canadian prairie soil

Sphingomonas paucimobilis , isolated from a soil in Manitoba, Canada, was able to utilize diclofop-methyl, (R,S)-methyl-2-[4-(2,4-dichlorophenoxy)phenoxy]propionate, as the sole source of carbon and energy. An actively growing aerobic culture completely degraded 1.5 μg diclofop-methyl ml⁻¹ to diclofop acid within 54 h, at 25°C. A biphasic growth pattern indicated that this organism was capable of degrading diclofop acid to 4-(2,4-dichlorophenoxy)phenol and 2,4-dichlorophenol and/or phenol. The accumulation of 2,4-dichlorophenol in the growth medium, however, suggested that Sphingomonas paucimobilis was unable to utilize this compound as a source of carbon and energy. Received 26 April 1999/ Accepted in revised form 30 July 1999     

Hydrolysis of isolated coffee mannan and coffee extract by mannanases of Sclerotium rolfsii

Different mannanase preparations obtained from the filamentous fungus Sclerotium rolfsii were used for the hydrolysis of coffee mannan, thus reducing significantly the viscosity of coffee extracts. Mannan is the main polysaccharide component of these extracts and is responsible for their high viscosity, which negatively affects the technological processing of instant coffee. Coffee mannan was isolated from green defatted Arabica beans by delignification, acid wash and subsequent alkali extraction with a yield of 12.8%. Additionally, coffee extract polysaccharides were separated by alcohol precipitation and were found to form nearly half of the coffee extract dry weight. These isolated mannans as well as the mannan in the coffee extract were efficiently hydrolysed by the S. rolfsii mannanase, which resulted in significant viscosity reductions. Concurrently, the reducing sugar content increased continuously due to the release of various mannooligosaccharides including mannotetraose, mannotriose, and mannobiose. Both a partially purified, immobilised and a soluble, crude mannanase preparation were successfully employed for the degradation of coffee mannan.