Acidification of lakes in Šumava (Bohemia) and in the High Tatra Mountains (Slovakia)

Acidification of lakes takes place when pH of rainwater is less than 4.5 and the catchments lie on sensitive geology. Both conditions are met for most lakes in Bohemia and Slovakia. Since 1978 we have studied mountain lakes in the Sumava and in the High Tatra Mountains. In Šumava the three lakes under study are of glacial origin. The catchments are small, with steep sides covered by spruce. The bedrocks are biotite-rich paragneiss, together with gneiss, quartzite and granite. In summer 1936 surface pH was 5.7–6.9 in the Lake Čertovo and 6.9–7.0 in the Lake Černé. Now the pH values are 4.3–4.8 in the two lakes and in the Lake Prášilské as well. Old reports on zooplankton are from the years 1871, 1892–96, 1935–37, 1947 and 1960. Since 1979 we have not found any planktonic Crustacea in the lakes Černé and Čertovo. Lake Prášilské is inhabited by Daphnia longispina and Cyclops abyssorum. In July 1989 the pH values were 4.4, 4.7 and 4.7, concentrations of labile monomeric Al were 0.83, 0.68 and 0.24 mg l^-1 in the lakes Čertovo, Černé and Prašilské, respectively. High levels of toxic Al compounds might be responsible for the extinction of planktonic Crustacea in the lakes Čertovo and Černé. All the three lakes are void of fish at present. In the High Tatra Mts. we examined more than 40 lakes above timberline in altitudes 1612–2145 m. They are all clearwater, naturally fishless lakes. The bedrock is granite. Owing to different levels of calcium the lakes are now in different stages of acidification. According to recent changes in the zooplankton they can be divided into three groups: (1) Species composition of planktonic Crustacea has not changed. (2) Planktonic Crustacea were present until 1973 but are absent now. (3) From the original species of Crustacea only Chydorus sphaericus is present. The three groups are well separated along the gradients of calcium, ANC and pH. They can be identified with the Henriksen's bicarbonate (our group 1), intermediate (our group 2) and acid (our group 3) lakes. We suppose that in the process of acidification the lakes of the group (2) have been shifted from oligotrophy to ultraoligotrophy.     

Regulation of biosynthesis of vermiculin and vermistatin inPenicillium vermiculatum

Biosynthesis of vermiculin (1) and vermistatin (2) inPenicillium vermiculatum can be controlled by the carbon and nitrogen sources. Glucose and sucrose affect the levels of the two metabolites; cornsteep liquor influences the quality the biosynthesis. The concentrations of Fe³⁺ and Cu²⁺ ions also affect the biosynthesis, the effect being dependent on the type of carbon source utilized. The compounds capable of electron transport generally stimulate the production of1 and2 but do not influence the biosynthesis qualitatively. Translated by Č. Novotny     

Platidiid brachiopods from the Middle Turonian of the Bohemian Cretaceous Basin (Czech Republic)

Small-sized platidiid brachiopods as yet unknown in the Bohemian Cretaceous Basin are described from the early Middle Turonian (Marginotruncana schneegansi Zone) nearshore deposits of the Zbyslav locality northeast of Čáslav. The studied specimens probably belong to the genusAemula Steinich, 1968, but cannot be precisely determined due to the poor preservation of internal characters. Most probably, they represent the stratigraphically earliest known populations of the family Platidiidae.     

Reduction of the nitrogen and carbon content in swine waste with algae and bacteria

Animal waste causes environmental problems like eutrophication of ground and surface water or the pollution of the atmosphere because of its high NH₄ ⁺ content. The aim of our study was to fix the nitrogen of swine waste as biomass. Therefore, an isolated alga, Chlorella sp., and bacteria naturally living in liquid manure were grown in batch cultures (containing diluted swine waste supplied with a nutrient solution) and continuous cultures (undiluted liquid manure) to achieve reduction of NH₄ ⁺ and total organic carbon (TOC) contents. For continuous cultivation, a photobioreactor of our own design was used. The batch cultivation of Chlorella sp. and bacteria in swine waste resulted in good growth of both groups of organisms and in a reduction of 25% NH₄ ⁺ and 80% TOC. In the continuous cultivation a steady state was not achieved owing to a change in the composition of the bacterial population. NH₄ ⁺ was totally removed, but NO₂ ⁻ (up to 100 mM) was transiently released. NO₃ ⁻ was not detected. These effects might be explained by the presence of heterotrophic nitrifiers, which are able to oxidize NH₄ ⁺ to NO₂ ⁻ and to reduce NO₂ ⁻ to gaseous compounds. Received: 21 January 1999 / Received revision: 9 March 1999 / Accepted: 14 March 1999     

Constitutive expression of extracellular peroxidase isoenzymes capable of oxidizing 4-hydroxystilbenes during the growth cycle of grapevine suspension cell cultures

The constitutive expression of peroxidase isoenzymes which are capable of oxidizing 4-hydroxystilbenes was studied during the growth cycle of suspension cell cultures from grapevine (Vitis vinifera L. cv. Monastrell) berries. the results showed that the growth of suspension cell cultures is accompanied by the constitutive expression of the peroxidase isoenzymes HSPrx 1 and HSPrx 2, previously characterised by their properties for oxidizing 4-hydroxystilbene, the expression of these isoenzymes being characteristic of Monastrell vines brought to a resistant state. However, although the differential catalytic properties of these grapevine isoenzymes are also shown by the horseradish peroxidase, no immunological relationships have been found between the peroxidases from either source. Communicated by I. MACHáČKOVá     

Continuous acetone-butanol-ethanol fermentation using SO2-ethanol-water spent liquor from spruce

SO₂–ethanol–water (SEW) spent liquor from spruce chips was successfully used for batch and continuous production of acetone, butanol and ethanol (ABE). Initially, batch experiments were performed using spent liquor to check the suitability for production of ABE. Maximum concentration of total ABE was found to be 8.79 g/l using 4-fold diluted SEW liquor supplemented with 35 g/l of glucose. The effect of dilution rate on solvent production, productivity and yield was studied in column reactor consisting of immobilized Clostridium acetobutylicum DSM 792 on wood pulp. Total solvent concentration of 12 g/l was obtained at a dilution rate of 0.21 h⁻¹. The maximum solvent productivity (4.86 g/l h) with yield of 0.27 g/g was obtained at dilution rate of 0.64 h⁻¹. Further, to increase the solvent yield, the unutilized sugars were subjected to batch fermentation.     

Mexican Arnica Anti–Inflammatory Action: Plant Age is Correlated with the Concentration of Anti–Inflammatory Sesquiterpenes in the Medicinal Plant <Emphasis Type="Italic">Heterotheca inuloides</Emphasis> Cass. (Asteraceae)<Superscript>1</Superscript>

Mexican Arnica Anti–Inflammatory Action: Plant Age Is Correlated with the Concentration of Anti–inflammatory Sesquiterpenes in the Medicinal Plant Heterotheca inuloides Cass. (Asteraceae). Mexican árnica (Heterotheca inuloides Cass.) is a widely used anti–inflammatory medicinal plant in Mexican folk medicine. Although it has been suggested that plant age, fertilization, and harvesting regime influence the concentration of secondary compounds affecting the therapeutic activity of the plant, the effect of these variables on the concentration of the Mexican árnica anti–inflammatory compounds was not known. We quantified anti–inflammatory sesquiterpenes (caryolan–1, 9β–diol, cadalen–15–oic acid, 7–hydroxycadalene, 4–hydroxy–2–isopropyl–4, 7–dimethyl–1[4H] naftalinone, 7–hydroxy–4αH–3, 4–dihydrocadalene, β–caryophyllene, and β–caryophyllene epoxide) in Mexican árnica plants subjected to fertilization and successive harvests of flowering stems, conditions that mimic the cultivation and harvesting for árnica in México. Fertilization and successive harvesting and their interaction had no significant effect on the concentration of anti–inflammatory compounds. However, the concentrations of these compounds were 60% higher in flowering stems from 15–month–old plants than in those from 4– or 8–month–old plants and was independent of the number of harvests and fertilization regime applied.     

Batch and repeated batch production of l(+)-lactic acid by Enterococcus faecalis RKY1 using wood hydrolyzate and corn steep liquor

Lactic acid production was investigated for batch and repeated batch cultures of Enterococcus faecalis RKY1, using wood hydrolyzate and corn steep liquor. When wood hydrolyzate (equivalent to 50 g l⁻¹ glucose) supplemented with 15–60 g l⁻¹ corn steep liquor was used as a raw material for fermentation, up to 48.6 g l⁻¹ of lactic acid was produced with, volumetric productivities ranging between 0.8 and 1.4 g l⁻¹ h⁻¹. When a medium containing wood hydrolyzate and 15 g l⁻¹ corn steep liquor was supplemented with 1.5 g l⁻¹ yeast extract, we observed 1.9-fold and 1.6-fold increases in lactic acid productivity and cell growth, respectively. In this case, the nitrogen source cost for producing 1 kg lactic acid can be reduced to 23% of that for fermentation from wood hydrolyzate using 15 g l⁻¹ yeast extract as a single nitrogen source. In addition, lactic acid productivity could be maximized by conducting a cell-recycle repeated batch culture of E. faecalis RKY1. The maximum productivity for this process was determined to be 4.0 g l⁻¹ h⁻¹.     

Effect of intense interval workouts on running economy using three recovery durations

The purposes of this study were to determine whether running economy (RE) is adversely affected following intense interval bouts of 10 × 400-m running, and whether there is an interaction effect between RE and recovery duration during the workouts. Twelve highly trained male endurance athletes [maximal oxygen consumption; V˙O_{2 max} =72.5 (4.3) ml·kg⁻¹·min⁻¹; mean (SD)] performed three interval running workouts of 10 × 400 m with a minimum of 4 days between runs. Recovery duration between the repetitions was randomly assigned at 60, 120 or 180 s. The velocity for each 400-m run was determined from a treadmill V˙O_{2 max} test. The average running velocity was 357.9 (9.0) m · min⁻¹. Following the workout, the rating of perceived exertion (RPE) increased significantly (P < 0.01) as recovery duration between the 400-m repetitions decreased (14.4, 16.1, and 17.7 at 180s, 120s, and 60 s recovery, respectively). Prior to and following each workout, RE was measured at speeds of 200 and 268 m · min⁻¹. Changes in RE from pre- to post-workout, as well as heart rate (HR) and respiratory exchange ratio (R) were similar for the three recovery conditions. When averaged across conditions, oxygen consumption (V˙O₂) increased significantly (P < 0.01) from pre- to post-test (from 38.5 to 40.5 ml · kg⁻¹ · min⁻¹ at 200 m · min⁻¹, and from 53.1 to 54.5 ml · kg⁻¹ · min⁻¹ at 268 m · min⁻¹, respectively). HR increased (from 124 to 138, and from 151 to 157 beats · min⁻¹ respectively) and R decreased (from 0.90 to 0.78, and from 0.93 to 0.89, respectively) at 200 and 268 m · min⁻¹, respectively (P < 0.01). This study showed that RE can be perturbed after a high-intensity interval workout and that the changes in V˙O₂, HR and R were independent of the recovery duration between the repetitions. Accepted: 23 June 1997     

Adrenocorticotropic Hormone and Cortisol Levels in Athletes and Sedentary Subjects at Rest and Exhaustion: Effects of Magnesium Supplementation

The effects of a 1-month exercise program and magnesium supplementation on the adrenocorticotropic hormone and cortisol levels were studied in young tae-kwon-do and sedentary subjects both at rest and exhaustion. The hormone levels were compared before and after supplementation with 10 mg of magnesium (as magnesium sulfate) per kilogram of body weight. Both exercise and magnesium supplements caused significant increases of the adrenocorticotropic hormone (p < 0.05). The cortisol levels were increased in training subjects receiving supplements (p < 0.05) but not so in subjects that either trained or received magnesium supplements in an independent manner. The cortisol levels measured in resting individuals were higher in the supplemented and non-supplemented athletes than those in sedentary subjects (p < 0.05). The results of this study show that exercise and/or magnesium supplementation causes a rise of the adrenocorticotropic hormone, whereas cortisol is increased only as a result of combined exhaustion and magnesium supplements.     

Magnesium Sulfate in Emergency Department Patients with Hypertension

To compare the effect of IV magnesium with other antihypertensives in emergency department (ED) patients with hypertension. ED patients with a systolic BP > 135 mmHg or diastolic BP > 85 were approached for entry into the study. Those granting consent were randomly placed into one of three treatment groups: (1) 1.5 gm IV MgSO₄ (n = 42), (2) a parenteral or oral antihypertensive agent (n = 41), (3) both IV MgSO₄ and an antihypertensive agent (n = 44). Systolic and diastolic blood pressures were measured at entry into the study and at 15, 30, 45, and 60 min after magnesium or other antihypertensive medications were given. The main outcome measure was blood pressure at 60 min, and results were compared using one-way analysis of variance with the post hoc Tukey HSD test. Compared to systolic and diastolic blood pressures at time 0, both were lower at 15, 30, 45, and 60 min in all groups (p < 0.05). No significant difference in systolic or diastolic BP at any time point was observed when response to treatment was compared between the three groups. Intravenous MgSO₄ is as effective as antihypertensives at lowering BP in emergency department patients.     

Critical factors in chitin production by fermentation of shrimp biowaste

Factors affecting Lactobacillus fermentation of shrimp waste for chitin and protein liquor production were determined. The objective of the fermentation is medium conditioning by Lactobacillus through production of proteases and lowering of the pH. The efficiency was tested by conducting fermentation of biowaste in 1-l beakers with or without pH adjustment using different acids. Addition of 5% glucose to the biowaste supported the growth of lactic acid bacteria and led to better fermentation. Among four acids tested to control pH at the start and during fermentation, acetic acid and citric acid proved to be the most effective. In biowaste fermented with 6.7% L. plantarum inoculum, 5% glucose, and pH 6.0 adjusted with acetic acid, 75% deproteination and 86% demineralization was achieved. Replacement of acetic acid by citric acid gave 88% deproteination and 90% demineralization. The fermentation carried out in the presence of acetic acid resulted in a protein fraction that smelled good and a clean chitin fraction. Received: 4 April 2000 / Received revision: 9 June 2000 / Accepted: 9 June 2000     

Cellulase production by six <Emphasis Type="Italic">Trichoderma</Emphasis> spp. fermented on medicinal plant processings

Capabilities of cellulase production, using delignified bioprocessings of medicinal and aromatic plants, viz. citronella (Cymbopogon winterianus) and Artemisia annua (known as marc of Artemisia) and garden waste (chiefly containing Cynodon dactylon), by the six species of Trichoderma were comparatively evaluated. Among the members of Trichoderma studied, T. citrinoviride was found to be the most efficient producer of cellulases along with a high level of β- glucosidase (produced 102.4 IU g⁻¹ on marc of Artemisia; 101.33 IU g⁻¹ on garden waste; 81.86 IU g⁻¹ on distillation waste of citronella and 94.77 IU g⁻¹ on pure cellulose). Although T. virens was noticed to be the minimal enzyme producer fungus, it interestingly could not produce complete cellulase enzyme complex on any test waste or pure cellulose, except on marc of Artemisia, where it produced all three enzymes of the complex. Immediate reduction in pH was also noticed during fermentation in the case of pure polymer (cellulose) by all tested fungi, while it was delayed with delignified agrowastes. The pH profile varied with the substrate used as well as with individual species of Trichoderma. On the other hand, no alteration in pH with any species of Trichoderma was noticed when grown on marc of A. annua, which might be due to the buffering capacity of this marc.     

Potential role of serum magnesium measurement as a biomarker of acute Falciparum malaria infection in adult patients

Serum magnesium concentration was measured in 80 adult patients (age range: 18–40 yr) presenting with acute, uncomplicated falciparum malaria infection and a control group of 20 age-matched, healthy individuals. The mean serum magnesium concentration in the patients was 1950.0 ±10.0 μg/dL. The control serum magnesium was 640.0±40.0 μg/dL. This represents an over threefold increase in serum magnesium levels above normal value, p<0.01. The key pathogenic event in acute falciparum malaria infection is the hemolysis of both infected and uninfected red blood cells. Therefore, the increased serum magnesium concentration might occur because of the hemolysis arising from erythrocytic merogony because red blood cells contain high amounts of magnesium. In conclusion, the increased serum magnesium has potential application as a biomarker of acute falciparum malaria infection in adults.     

Increased erythritol production in fed-batch cultures of Torula sp. by controlling glucose concentration

The effect of glucose concentration on erythritol production by Torula sp. was investigated. The maximum volumetric productivity of erythritol was obtained at an initial glucose concentration of 300 g l⁻¹ in batch culture. The volumetric productivity was maximal at a controlled glucose concentration of 225 g l⁻¹, reducing the lag time of the erythritol production. A fed-batch culture was established with an initial glucose concentration of 300 g l⁻¹ and with a controlled glucose concentration of 225 g l⁻¹ in medium containing phytic acid as a phosphate source. In this fed-batch culture, a final erythritol production of 192 g l⁻¹ was obtained from 400 g l⁻¹ glucose in 88 h. This corresponded to a volumetric productivity of 2.26 g l⁻¹ h⁻¹ and a 48% yield. Journal of Industrial Microbiology & Biotechnology (2001) 26, 248–252. Received 26 September 2000/ Accepted in revised form 16 January 2001     

Effect of activators and inhibitors on the activity of mitochondrial DNA polymerase

At a concentration of 0.5 to 3 mmol/L, ATP stimulates the activity of mitochondrial DNA polymerase ofNeurospora crassa under the optimum reaction conditions; at higher concentrations, an inhibitory effect is observed. 4-Chloromercuribenzoate (1 mmol/L), a thiol inhibitor, decreases the enzyme activity two-fold, while N-ethylmaleimide (2 mmol/L) has no effect. Ethidium bromide (up to 10 μmol/L) and heparin (up to 0.4 μg/mL) reduce the activity by 60%. ddTTP does not affect the DNA polymerase reaction. The bestin vitro template is the activated calf-thymus DNA. 2nd report of the series Mitochondrial DNA polymerase from the poky mutant ofNeurospora crassa; 1st report:Biológia (Bratislava) 45, 601–606 (1990). Translated by Č. Novotny     

Comparison of Hypoglycemic Activity of Trace Elements Absorbed in Fermented Mushroom of <Emphasis Type="Italic">Coprinus comatus</Emphasis>

The effect of fermented mushroom of Coprinus comatus rich in trace elements, including vanadium, chromium, zinc, magnesium, copper, iron, and nickel, on glycemic metabolism was studied in this paper. Alloxan-induced hyperglycemic mice were used in the study. The blood glucose, glycohemoglobin, and glycogen synthesis of the mice were analyzed, respectively. At the same time, the gluconeogenesis of the normal mice was also determined. After the mice were administered (ig) with C. comatus rich in vanadium (CCRV), the blood glucose and the glycohemoglobin of alloxan-induced hyperglycemic mice decreased (p < 0.05, p < 0.01), glycogen synthesis of alloxan-induced hyperglycemic mice elevated (p < 0.01), the gluconeogenesis of the normal mice was inhibited (p < 0.01), and the sugar tolerance of the normal mice was improved. However, the same result did not occur in other groups. Vanadium at lower doses in combination with C. comatus induced significant effect on glycemic metabolism in mice.     

Degradation of p-nitrophenol and pentachlorophenol mixtures by Sphingomonas sp. UG30 in soil perfusion bioreactors

The degradation of mixtures of pentachlorophenol (PCP) and p-nitrophenol (PNP) were evaluated in pure cultures of Sphingomonas sp. UG30, statically incubated soils (60% water-holding capacity) and soil perfusion bioreactors where encapsulated cells of UG30 were used as a soil inoculant. In pure-culture studies, conditions were optimized for mineralization of PCP and PNP mixtures at concentrations of 30 mg l⁻¹ each. Optimum in vitro mineralization of PCP and PNP mixtures by UG30 was facilitated using ammonium phosphate as a nitrogen source, while inhibition was observed with ammonium nitrate. The bioreactor system used columns containing soil treated with mixtures of 100, 225 or 500 mg kg⁻¹ of PCP and PNP. Rapid dissipation of both substrates was observed at the 100 mg kg⁻¹ level. Inoculation with UG30 enhanced PCP degradation at the 100 mg kg⁻¹ level in bioreactors but not in static soil microcosms. At higher PCP and PNP concentrations (225 mg kg⁻¹), occasional complete degradation of PNP was observed, and PCP degradation was about 80% compared to about 25% in statically incubated soils after 20 days at 22°C. There was no additional degradation of the PCP and PNP mixtures attributable to inoculation with encapsulated cells of UG30 in either soil system at concentrations of 225 or 500 mg kg⁻¹. Journal of Industrial Microbiology & Biotechnology (2000) 25, 93–99. Received 25 February 2000/ Accepted in revised form 07 June 2000     

Ethanol production from hardwood spent sulfite liquor using an adapted strain of Pichia stipitis

Conditions have been optimized for fermentation of pretreated hardwood spent sulfite liquor (HSSL) using an adapted strain of Pichia stipitis. The pretreatments, consisting of boiling and overliming with Ca(OH)₂ of HSSL, to partially remove inhibitors, and adaptation of the yeast strain to HSSL, were both critical for a successful fermentation. Ethanol concentration was increased from 6.7 to 20.2 g l⁻¹ using adapted P. stipitis (A) and pretreated HSSL. The maximum ethanol yield (Y _p/s) and productivity (Q _p) were 0.41 g g⁻¹ and 0.44 g l⁻¹ h⁻¹, respectively, at an oxygen transfer rate of 2.0 mmol O₂ l⁻¹ h⁻¹. The optimized results with this strain were compared to those of other xylose-fermenting yeasts and Saccharomyces cerevisiae (SSL-acclimatized) currently used at an industrial plant for the fermentation of spent sulfite liquor. Journal of Industrial Microbiology & Biotechnology (2001) 26, 145–150. Received 23 June 2000/ Accepted in revised form 21 October 2000