In Vitro Antifungal Activity of Micafungin and Caspofungin Against Dermatophytes Isolated from China

Aims

The aims of this study are to investigate the in vitro activities of micafungin and caspofungin that are two new echinocandin antifungal drugs against clinically isolated dermatophytes in China and to define MEC (minimal effective concentration) as the reading endpoints of this study in accordance with (Clinical and laboratory Standards Institute) CLSI M38-A2 reference.

Methods

Minimal effective concentrations (MECs) of micafungin and caspofungin for 82 dermatophyte strains were determined according to CLSI (formerly NCCLS) M38-A2 broth microdilution methods.

Results

(1) The MEC_90s of micafungin for Trichophyton violaceum and Trichophyton tonsurans were 0.25 μg/mL, and for Microsporum canis and Trichophyton verrucosum were 0.06 μg/mL. The MEC_90s for Trichophyton rubrum, Trichophyton mentagrophytes, Microsporum gypseum and Epidermophyton floccosum were 0.03 μg/mL. (2) The MEC_90s of caspofungin for T. rubrum, T. violaceum and T. tonsurans were 1 μg/mL, and for T. mentagrophytes, M. canis, M. gypseum, E. floccosum and T. verrucosum were 0.5 μg/mL. (3) Compared with caspofungin, micafungin demonstrated lower MEC value to dermatophytes (P < 0.05).

Conclusions

Micafungin has stronger in vitro antifungal activity than caspofungin.     

In vitro activity of micafungin against biofilms of <Emphasis Type="Italic">Candida albicans</Emphasis>, <Emphasis Type="Italic">Candida glabrata</Emphasis>, and <Emphasis Type="Italic">Candida parapsilosis</Emphasis> at different stages of maturation

Candida spp. is able to form a biofilm, which is considered resistant to the majority of antifungals used in medicine. The aim of this study was to evaluate the in vitro activity of micafungin against Candida spp. biofilms at different stages of their maturation (2, 6, and 24 h). We assessed the inhibitory effect of micafungin against 78 clinical isolates of Candida spp., growing as planktonic or sessile cells, by widely recommended broth microdilution method. The in vitro effect on sessile cells viability was evaluated by colorimetric reduction assay. All examined strains were susceptible or intermediate to micafungin when growing as planktonic cells. At the early stages of biofilm maturation, from 11 (39.3%) to 20 (100%), tested strains, depending on the species, exhibited sessile minimal inhibitory concentrations (SMICs) of micafungin at ≤ 2 mg/L. For 24-h-old Candida spp. biofilms, from 3 (10.7%) to 20 (100%) of the tested strains displayed SMICs of micafungin at ≤ 2 mg/L. Our findings confirm that micafungin exhibits high potential anti-Candida-biofilm activity. However, this effect does not comprise all Candida species and strains. All strains were susceptible or intermediate to micafungin when growing as planktonic cells, but for biofilms, micafungin displays species- and strain-specific activity. Paradoxical growth of C. albicans and C. parapsilosis was observed. Antifungal susceptibility testing of Candida spp. biofilms would be the best solution, but to date, no reference method is available. The strongest antibiofilm activity of micafungin is observed at early stages of biofilm formation. Possibly, micafungin could be considered as an effective agent for prevention of biofilm-associated candidiasis, especially catheter-related candidaemia.     

Food plant density,patch isolation and vegetation height determine occurrence in a Swedish metapopulation of the marsh fritillary <Emphasis Type="Italic">Euphydryas aurinia</Emphasis> (Rottemburg, 1775) (Lepidoptera,Nymphalidae)

The occurrence pattern of the marsh fritillary was studied within a patch network on the Baltic island Öland, Sweden. Presence/absence was established for potentially suitable habitat patches (n = 158) on calcareous moist grassland and analyzed in a multiple logistic regression model where patch area, patch isolation and nine habitat quality variables were included as explanatory variables. Larval food plant density was positively, and patch isolation negatively, correlated to the presence of Euphydryas aurinia. Area did not contribute to the explanation of the occurrence pattern. Significant interactions between larval food plant density times patch isolation, and larval food plant density times vegetation height, show that with low food plant density the butterfly primarily occurs in patches with a vegetation height of 4–10 cm, within a distance of 250 m from nearest occupied patch. In patches with a high food plant density the butterfly occurs in patches where the vegetation height is higher, 4–16 cm, and the distance to nearest occupied patch can be longer, up to 1.4 km. This study supports earlier findings in other regions, suggesting that a network of adjacent patches with a high food plant density and a vegetation height within the preferred threshold, despite their size, is an apparent conservation goal.     

Sex ratios and population persistence in the rare shrub Lindera subcoriacea Wofford

Biased sex ratios can have conservation consequences for dioecious plant species with small population sizes because of an increased risk of single sex populations. Biased sex ratios have been observed in two of the three species of Lindera (Lauraceae) in the eastern United States, but have not been documented for Lindera subcoriacea, a rare shrub of the southeastern USA. We inventoried 78 of 118 populations in North Carolina over a 3 year period, documenting the location, community type, and sex, of 299 individuals. In addition, we measured the stem height and diameter for 245 individuals. We examined population persistence relative to historical population size estimates. Average population size was 7.9 individuals and 72 % of visited populations were extant. There was a significant positive correlation between historical estimates of population size and persistence. Lindera subcoriacea consistently had male-biased (58 %) sex ratios across all population sizes and vegetation communities. Males and females had similar stem heights (mean 200.4 vs. 187.8 cm, respectively) and diameters (1.3 vs. 1.2 cm, respectively) across years and were not spatially segregated within populations. It is unclear at what stage biased sex ratios arise in L. subcoriacea, but results suggest that the causes operate across vegetation communities and population sizes. The weak bias exhibited in L. subcoriacea sex ratios has limited implications for the species’ conservation except where spatially isolated populations are unisexual. Given the vulnerability of small L. subcoriacea populations to extirpation, they should be high priority targets for management.     

Comparison of Killing Activity of Micafungin Against Six <Emphasis Type="Italic">Candida</Emphasis> Species Isolated from Peritoneal and Pleural Cavities in RPMI-1640, 10 and 30% Serum

Currently echinocandins are recommended in Candida peritonitis and pleuritis. We determined micafungin killing rates (k values) at therapeutic concentrations (0.25–2 mg/L) in RPMI-1640 with and without 10 and 30% serum mimicking in vivo conditions against six Candida species isolated from peritoneal and pleural fluid. In RPMI-1640, micafungin was fungicidal against C. glabrata, C. krusei and C. kefyr within 2.27?±?10.68, 2.69?±?10.29 and 3.10?±?4.41 h, respectively, while was fungistatic against C. albicans, C. tropicalis and C. parapsilosis. In 10% serum, ≥?0.25, ≥?0.5, ≥?0.5 and ≥?1 mg/L micafungin produced positive k values (killing) for all C. albicans, C. glabrata, C. kefyr and C. krusei, respectively. In 30% serum, 2 mg/L micafungin produced killing against all C. albicans, C. glabrata and C. kefyr isolates, but was ineffective against C. krusei, C. parapsilosis and 2 of 3 C. tropicalis. Micafungin exposure should be increased against non-albicans species to eradicate fungi from peritoneal and pleural cavities.     

Variability of polar scurvygrass Cochlearia groenlandica individual traits along a seabird influenced gradient across Spitsbergen tundra

In the resource-limited Arctic environment, vegetation developing near seabird colonies is exceptionally luxuriant. Nevertheless, there are very few detailed quantitative studies of any specific plant species responses to ornithogenic manuring. Therefore, we studied variability of polar scurvygrass Cochlearia groe nlandica individual biomass and leaf width along a seabird influenced gradient determining environmental conditions for vegetation in south-west Spitsbergen. We found seabird colony effect being a paramount factor responsible for augmented growth of C. groenlandica. The species predominated close to the colony and reached the highest mean values of individual biomass (1.4 g) and leaf width (26.6 mm) 10 m below the colony. Its abundance and size declined towards the coast. Both C. groenlandica individual traits significantly decreased with distance from the colony, soil water and organic matter content and increased with guano deposition, soil δ ¹⁵N, conductivity, acidity and nitrate, phosphate and potassium ion content. Our study supports the hypothesis that seabirds have fundamental importance for vegetation growth in poor Arctic environment. Highly plastic species such as C. groenlandica may be a useful instrument in detecting habitat condition changes, for instance resulting from climate change.     

Production of laccase from Trametes versicolor by solid-state fermentation using olive leaves as a phenolic substrate

The aim of the present study was to investigate whether olive leaves were feasible as a substrate for laccase production by the white-rot fungus Trametes versicolor FPRL 28A INI under solid-state fermentation conditions. Different experiments were conducted to select the variables that allow obtaining high levels of laccase activity. In particular, the effects of the initial moisture content, substrate particle size, supplementation with inorganic and organic nitrogen sources were evaluated. Highest laccase activity (276.62 ± 25.67 U/g dry substrate) was achieved with 80 % initial moisture content and 1.4–1.6 mm particle size of the substrate supplemented with yeast extract (1 % (w/w) nitrogen). Such a high activity was obtained without any addition of inducers.     

The role of floods in the lives of fish-eating birds: predator loss or benefit?

Floods accompanied by high flow and high water turbidity are usually believed to cause problems to fish-eating birds and mammals searching visually for their prey. In the present study the diets of breeding kingfishers were studied during the normal river situation and during a long-lasting flood event with respect to diet composition, size of fish prey and food diversity index. During the normal situation (flow 1.75 m³ s^?1, Secchi disc depth 0.5–1 m), the diet of a kingfisher was dominated by benthic fish species (52.9% by numbers, 63.9% by weight), the average size of fish taken was 6.5 cm L _T and 3.0 g and the food diversity index reached its lowest value (1.57). In contrast, during the long-lasting flood event (flow 5–28 m³ s^?1, Secchi disc depth 0.03–0.4 m) the diet of the kingfisher was dominated by sub-surface fish species (72.4% by numbers, 76.1% by weight) and both the average size of fish taken (7.4 cm L _T and 3.7 g) and the food diversity index (1.83) increased significantly. The birds provided their nestlings with lower numbers of fish of larger sizes, which resulted in very similar weights of the young birds prior to fledging when the flood and normal situations were compared. This study provides evidence that in different foraging conditions the kingfishers adopt different foraging strategies to maintain their high breeding success.     

Above- and belowground dynamics of plant community succession following abandonment of farmland on the Loess Plateau, China

Aboveground and belowground changes during vegetation restoration and vegetation successions need to be characterized in relation to their individual responses to changes in soil resources. We examined above- and belowground vegetation characteristics, soil moisture, and nutrient status at the end of the growing season in 2006 in plots with vegetation succession ages of 2, 4, 6, and 8 years (two replicates each) that had been established on abandoned cropland, where potatoes had been grown for 3 years, using hoe and plow cultivation, immediately prior to vegetation clearance and subsequent natural plant colonization. A plant community comprising pioneer species [e.g., Artemisia capillaries, (subshrub)] was characterized by low levels of species richness (7.5?±?1.4 species m^?2), plant density (35.7?±?4.2 stems m^?2), fine root length density (940.1?±?90.1 m m^?2), and root area density (2.3?±?0.3 m² m^?2) that increased rapidly with time. Aboveground and belowground characteristics of both A. capillaries and the later successional species, Stipa bungeana (C3 perennial grass), increased in the first 6 years, but in the following 2 years A. capillaries declined while S. bungeana thrived. Thus, the fine root length density of A. capillaries, 812.4 m m^?2 after 2 years, changed by a factor of 1.7, 2.0, and 0.4 in the 4th, 6th, and 8th years, whereas that of S. bungeana changed from 278.4 m m^?2, after 4 years, and by 1.7 and 23.3 times in the 6th and 8th years, respectively. Secondary vegetation succession resulted in reduced soil moisture contents. Soil available P and N mainly influenced aboveground characteristics, while soil moisture mainly influenced belowground characteristics. However, soil moisture had no significant affect on S. bungeana belowground characteristics at the population level in this semiarid region.     

The endangered damselfly <Emphasis Type="Italic">Coenagrion ornatum</Emphasis> in post-mining streams: population size,habitat requirements and restoration

The damselfly Coenagrion ornatum represents a threatened species of lowland headwater streams. Although the species is threatened in Western and Central Europe, it is known at a system of post-mining drainage ditches in the Radovesicka spoil heap (northwestern Bohemia, Czech Republic). This study aimed to estimate its population size in this post-mining stream system, and to explore habitat preferences of both its larvae and adults with respect to various environmental factors. The adults were captured-recaptured along 5.2 km of the ditches in June 2012; larvae were sampled in 64 study sites (i.e., 27-meter-long sections of the same ditches) in April 2012. The adult population size was estimated via log-linear models with the robust design on 4544 individuals (1560?±?391 females and 2983?±?298 males). Larvae were present in a third of the sections. GLMs revealed that both larvae and adults required emergent vegetation with a high proportion of Eleocharis spp. plants. The adults preferred the slow-flowing and shallow streams with 2-meter-high banksides covered by intermediately tall vegetation (~40 cm), whereas the larval abundance was supported by a high in-stream vegetation heterogeneity and a patchy cover of rocks on the streambeds. These results indicate that the post-mining streams could represent a valuable secondary habitat for the complete life cycle of this relatively large population of the endangered headwater specialist. Therefore, we recommend consideration of the conservation potential of such ditches during post-mining sites restoration and their subsequent management.     

High genetic structure of the Cozumel Harvest mice,a critically endangered island endemic: conservation implications

We assessed the genetic structure and diversity of Reithrodontomys spectabilis, a critically endangered, endemic rodent from Cozumel Island, México. A total of 90 individuals were trapped from September 2001 to January 2005. Microsatellite data analysis revealed high genetic diversity values: a total of 113 alleles (average 12.5 per locus), H _o  = 0.78, H _e  = 0.80. These high values can be related to Cozumel’s size (478 km²) and extensive native vegetation cover, factors that could be promoting a suitable population size, high heterozygosity and the persistence of rare alleles in the species, as well as some long-term movement of individuals between sampling localities. A strong genetic structure was also observed, with at least four genetic groups, associated with a pattern of isolation by distance. We found a strong allelic and genetic differentiation shown between localities, with negligible recent gene flow and low inbreeding coefficients. The species life history and ecological characteristics—being nocturnal, semi-terrestrial, a good tree climber, having lunar phobia and significant edge effect—are likely affecting its genetic structure and differentiation. The high genetic diversity and population structure award R. spectabilis a significant conservation value. Our results can serve as a basis for future research and conservation of the species, particularly considering the problems the island is facing from habitat perturbation, urbanization and introduction of exotic species. In view of the structure and genetic variability observed, it is essential to establish and reinforce protected areas and management programs for the conservation of the endemic and endangered Cozumel Harvest mice.     

Effect of vegetation data collection strategies on estimates of relevant source area of pollen (RSAP) and relative pollen productivity estimates (relative PPE) for non-arboreal taxa

Thirteen surface moss samples were collected for pollen analysis from an area of heathland in western Norway. Vegetation composition at different distances around the sampling locations was measured using three different survey methods; rooted frequency within a sub-divided 1 m × 1 m quadrat, visual estimates of cover within a 1 m × 1 m quadrat and a modified form of the ‘circle-walking method’. Extended R-value analysis was used to explore the pollen–vegetation relationships for five main taxa, Calluna vulgaris, Vaccinium-type, Cyperaceae, Poaceae and Potentilla-type. The estimates of relevant source area of pollen obtained were similar regardless of the vegetation survey method. Values obtained were always under 4 m. However, estimates of relative pollen productivity and the background pollen component (proportion of pollen coming from vegetation growing beyond the relevant source area of pollen) differ markedly depending on the method of vegetation survey chosen. This has important implications for the quantitative reconstruction of past vegetation cover.     

Effect of water table on greenhouse gas emissions from peatland mesocosms

Peatland landscapes typically exhibit large variations in greenhouse gas (GHG) emissions due to microtopographic and vegetation heterogeneity. As many peatland budgets are extrapolated from small-scale chamber measurements it is important to both quantify and understand the processes underlying this spatial variability. Here we carried out a mesocosm study which allowed a comparison to be made between different microtopographic features and vegetation communities, in response to conditions of both static and changing water table. Three mesocosm types (hummocks?+?Juncus effusus, hummocks?+?Eriophorum vaginatum, and hollows dominated by moss) were subjected to two water table treatments (0–5 cm and 30–35 cm depth). Measurements were made of soil-atmosphere GHG exchange, GHG concentration within the peat profile and soil water solute concentrations. After 14 weeks the high water table group was drained and the low water table group flooded. Measurement intensity was then increased to examine the immediate response to change in water table position. Mean CO₂, CH₄ and N₂O exchange across all chambers was 39.8 μg m^?2 s^?1, 54.7 μg m^?2 h^?1 and ?2.9 μg m^?2 h^?1, respectively. Hence the GHG budget was dominated in this case by CO₂ exchange. CO₂ and N₂O emissions were highest in the low water table treatment group; CH₄ emissions were highest in the saturated mesocosms. We observed a strong interaction between mesocosm type and water table for CH₄ emissions. In contrast to many previous studies, we found that the presence of aerenchyma-containing vegetation reduced CH₄ emissions. A significant pulse in both CH₄ and N₂O emissions occurred within 1–2 days of switching the water table treatments. This pulsing could potentially lead to significant underestimation of landscape annual GHG budgets when widely spaced chamber measurements are upscaled.     

Tidal and seasonal effects on survival rates of the endangered California clapper rail: does invasive Spartina facilitate greater survival in a dynamic environment?

Invasive species frequently degrade habitats, disturb ecosystem processes, and can increase the likelihood of extinction of imperiled populations. However, novel or enhanced functions provided by invading species may reduce the impact of processes that limit populations. It is important to recognize how invasive species benefit endangered species to determine overall effects on sensitive ecosystems. For example, since the 1990s, hybrid Spartina (Spartina foliosa × alterniflora) has expanded throughout South San Francisco Bay, USA, supplanting native vegetation and invading mudflats. The endangered California clapper rail (Rallus longirostris obsoletus) uses the tall, dense hybrid Spartina for cover and nesting, but the effects of hybrid Spartina on clapper rail survival was unknown. We estimated survival rates of 108 radio-marked California clapper rails in South San Francisco Bay from January 2007 to March 2010, a period of extensive hybrid Spartina eradication, with Kaplan–Meier product limit estimators. Clapper rail survival patterns were consistent with hybrid Spartina providing increased refuge cover from predators during tidal extremes which flood native vegetation, particularly during the winter when the vegetation senesces. Model averaged annual survival rates within hybrid Spartina dominated marshes before eradication (? = 0.466) were greater than the same marshes posttreatment (? = 0.275) and a marsh dominated by native vegetation (? = 0.272). However, models with and without marsh treatment as explanatory factor for survival rates had nearly equivalent support in the observed data, lending ambiguity as to whether hybrid Spartina facilitated greater survival rates than native marshland. Conservation actions to aid in recovery of this endangered species should recognize the importance of available of high tide refugia, particularly in light of invasive species eradication programs and projections of future sea-level rise.     

Seed size and recruitment limitation influence seedling establishment in three tallgrass prairie species

A seed size–seed number tradeoff predicts that large numbers of seeds have an establishment advantage under low levels of competition, while large seed size is advantageous under asymmetric competition. Testing these predictions in the context of tallgrass prairie restoration should increase predictability of outcomes of species composition—restoration technique combinations. I conducted field and greenhouse experiments comparing seedling establishment among three tallgrass prairie species with different seed mass-seed number combinations, but with similar mass of seeds sown. Species were prairie dock [Silphium terebinthinaceum, mass = 33.2 + 2.1 mg ( \(\overline{x}\)  + SE, n = 100)], wild quinine (Parthenium integrifolium, mass = 3.1 + 0.3 mg), and smooth blue aster (Symphyotrichum laeve var. laeve, mass = 0.53 + 0.02 mg). Seeds were sown into mowed or tilled plots with shade and mulch treatments in an old field in northeastern Illinois USA, and seeds were sown into containers with or without vegetative cover in a greenhouse. In mowed plots, species with larger numbers of seeds sown had higher seedling densities. In tilled plots, seedling densities of the large-seeded Silphium were reduced less by shade than the small-seeded Parthenium. Symphyotrichum, however, did not respond to treatments as expected based on its seed size. High relative growth rate possibly increased Symphyotrichum seedling establishment in competitive environments. Results of this study demonstrated recruitment limitation when seedlings established into existing vegetation, and suggest that species composition resulting from specific seeding rates during prairie restoration may be more predictable when species are interseeded into existing vegetation, than when seeds are sown into tilled fields.     

The capacity for paracellular absorption in the insectivorous bat Tadarida brasiliensis

Water-soluble nutrients are absorbed by the small intestine via transcellular and paracellular processes. The capacity for paracellular absorption seems greater in fliers than in nonfliers, although that conclusion rests mainly on a comparison of flying birds and nonflying mammals because only two frugivorous bat species have been studied. Furthermore, the bats studied so far were relatively large (>85 g, compared with most bat species which are <20 g) and were not insectivores (like about 70 % of bat species). We studied the small (11 g) insectivorous bat Tadarida brasiliensis and tested the prediction that the capacity for paracellular absorption would be as high as in the other bat and avian species studied so far, well above that in terrestrial, nonflying mammals. Using standard pharmacokinetic technique, we measured the extent of absorption (fractional absorption = f) of inert carbohydrate probes: L-arabinose (MM = 150.13) absorbed exclusively by paracellular route and 3OMD-glucose (MM = 194) absorbed both paracellularly and transcellularly. As predicted, the capacity of paracellular absorption in this insectivorous bat was high (L-arabinose f = 1.03 ± 0.14) as in other frugivorous bats and small birds. Absorption of 3OMD-glucose was also complete (f = 1.09 ± 0.17), but >80 % was accounted for by paracellular absorption. We conclude that passive paracellular absorption of molecules of the size of amino acids and glucose is extensive in this bat and, generally in bats, significantly higher than that in nonflying mammals, although the exact extent can be somewhat lower or higher depending on molecule size, polarity and charge.     

Comparative Pathogenicity of <Emphasis Type="Italic">Lomentospora prolificans</Emphasis> (<Emphasis Type="Italic">Scedosporium prolificans</Emphasis>) Isolates from Mexican Patients

We identified 11 Lomentospora prolificans isolates recovered from Mexican patients using phenotypic and molecular characteristics. The identification of isolates was assessed by internal transcribed spacer (ITS rDNA) sequencing. In vitro susceptibility to amphotericin B, fluconazole, voriconazole, posaconazole, caspofungin, anidulafungin and micafungin was determined according to Clinical and Laboratory Standards Institute (CLSI) procedures. Three isolates (07-2239, 11-2242 and 04-2673) were used to induce systemic infection in immunocompetent ICR mice. Survival and tissue burden studies were used as markers of pathogenicity. All of the strains were resistant to every antifungal tested with MIC’s for AmB (8–>8 µg/ml), VRC (16–>16 µg/ml), PSC (16–>16 µg/ml), FLC (64–>64 µg/ml) and echinocandins with MICs ≥8 µg/ml. One hundred, ninety and sixty percent of the infected mice with the strains 07-2239, 11-2242 and 04-2673 died during the study, respectively. Regarding tissue burden, the highest fungal load of the infected mice was detected in brain followed by spleen and kidney, regardless of the strain.     

Runoff and erosion from volcanic soils affected by fire: the case of Austrocedrus chilensis forests in Patagonia, Argentina

Aims

We characterized the runoff and erosion from a volcanic soil in an Austrocedrus chilensis forest affected by a wildfire, and we evaluated the effects of a mitigation treatment.

Methods

Rainfall simulations were performed in the unburned and burned forest, with and without vegetation cover, and under a mitigation treatment.

Results

After the wildfire, the mean infiltration rate decreased from 100 mm?h^?1 in unburned soils to 51 and 64 mm?h^?1 in the burned with and without litter and vegetation cover, respectively. The fast establishment of bryophytes accelerated the recovery of soil stability. Sediment production was negligible in the control plots (4.4 g?m^?2); meanwhile in the burned plots, it was 118.7 g?m^?2 and increased to 1026.1 g?m^?2 in the burned and bare plots. Total C and N losses in the control plots were negligible, while in the burned and bare plots the organic C and total N removed were 98.25 and 1.64 g?m², respectively. The effect of mitigation treatment was efficient in reducing the runoff, but it did not affect the sediment production.

Conclusions

These fertile volcanic soils promoted the recovery of vegetation in a short time after the wildfire, diminishing the risk of erosion.     

Effect of caffeine concentration on biomass production, caffeine degradation, and morphology of Aspergillus tamarii

The aim of the present study was to evaluate the effect of the initial caffeine concentration (1–8 g/L) on growth and caffeine consumption by Aspergillus tamarii as well as pellet morphology, in submerged fermentation. Caffeine was used as sole nitrogen source. At 1 g/L of initial caffeine concentration, caffeine degradation was not affected, resulting in a production of 8.7 g/L of biomass. The highest biomass production (12.4–14.8 g/L) was observed within a range of 2 to 4 g/L of initial caffeine concentration. At these initial caffeine concentrations, after 96 h of fermentation, 41–51 % of the initial caffeine was degraded. Using an initial caffeine concentration of 2–3 g/L, the highest specific growth rate was observed (μ?=?0.069 1/h). Biomass production decreased at 8 g/L of initial caffeine concentration. A. tamarii formed mainly pellets at all concentrations tested. The size of the pellet decreased at a caffeine concentration of 8 g/L.     

Variation in annual pollen accumulation rates of Fagus along a N–S transect in Europe based on pollen traps

Annual pollen-accumulation rates (PAR) of Fagus (beech) obtained within the framework of the Pollen Monitoring Programme (PMP) were analyzed in pollen traps along a N–S transect from the Baltic Sea to the Black Sea in different European vegetation units. The study regions are situated in the lowlands of northern Poland, the uplands of SE Poland, the Czech Krkono?e Mts, the Czech ?umava Mts, the Swiss Jura Mts, the Swiss Alps, the Bulgarian Rila Mts and the Bulgarian Strandzha Mts. Most time series are 10 or 11 years long, some are 5–16 years long. Inter-annual fluctuations in Fagus PAR were analyzed and compared with seed mast years. Years with high Fagus PAR and others with low Fagus PAR occurred most frequently in parallel within each region and often in two neighbouring regions. 2006 was exceptional as it had a very high Fagus sylvatica pollen deposition in all study regions and it was also a mast year. In Bulgaria, the trend in the 5 years of Fagus orientalis PAR in the Strandzha Mts differed from that of F. sylvatica PAR in the Rila Mts. Aiming at establishing the relationship between average Fagus PAR and tree cover, differences in Fagus PAR (averaged per pollen trap) were related in each region to the proportion of beech trees in the vegetation within 2 km of the pollen traps, the distance to the nearest pollinating Fagus tree, regional or local presence of beech forests, the degree of landscape openness, and the size of forest opening in which a trap is situated. Average Fagus PAR was found to track the regional abundance of beech trees in the vegetation, not the distance of the nearest Fagus tree. Regional occurrence of beech-dominated forests was reflected by a Fagus PAR of ca. 1,400 grains cm^?2 year^?1, local abundance very close to pollen traps by ca. 2,400 grains, small patches of forest with admixture of Fagus by ca. 170–220 grains, and scarcity or absence of Fagus by ca. 40 grains or less.