Evaluation of Growth Yield of Spirulina maxima in Photobioreactors

The paper deals with the evaluation of the parameters for the cultivation of Spirulina maxima in two reactors (large-laboratory scale (LL) and semi-technical scale (ST)), whose illuminated areas in respect of the illuminated volume are different, and with the operating costs. We evaluated the growth yield coefficients for Spirulina maxima cultures. In the LL, the following factors were identified: YO2/X – 65.5; YX/CO2 – 0.0806; YX/P2O5 – 0.0082, while in the ST: YO2/X – 583; YX/CO2 – 0.017; YX/P2O5 – 0.0023. Although the reactor in the ST was equipped with many devices that should have improved the efficiency of cultivation, the obtained result was lower compared to the culture conducted in the LL. It was proved that it was possible to perform the cultivation of Spirulina maxima under temperate climate conditions in simply constructed, low cost reactors

Anaerobic Digestion: I. A Common Process Ensuring Energy Flow and the Circulation of Matter in Ecosystems. II. A Tool for the Production of Gaseous Biofuels

Anaerobic digestion, a process that ultimately generates methane and carbon dioxide, is common in natural anoxic ecosystems where concentrations of electron acceptors such as nitrate, the oxidized forms of metals and sulphate are low. It also occurs in landfill sites and wastewater treatment plants. The general scheme of anaerobic digestion is well known and comprises four major steps: (i) hydrolysis of complex organic polymers to monomers; (ii) acidogenesis that results in the formation of hydrogen and carbon dioxide as well as non-gaseous fermentation products that are further oxidized to hydrogen, carbon dioxide and acetate in (iii) acetogenesis based on syntrophic metabolism and (iv) methanogenesis. Approaches to the analysis of methane-yielding microbial communities and data acquisition are described. There is currently great interest in the development of new technologies for the production of biogas (primarily methane) from anaerobic digestion as a source of renewable energy. This includes the modernization of landfill sites and wastewater treatment plants and the construction of biogas plants. Moreover, research effort is being devoted to the idea of separating hydrolysis and acidogenesis from acetogenesis and methanogenesis under controlled conditions to favour biohydrogen and biomethane production, respectively. These two stages occur under different conditions and are carried out in separate bioreactors

19 Radioterapia ziarnicy złośliwej u dzieci w materiale I Zakładu Teleradioterapii Centrum

W latach 1986–1998 w I Zakładzie Radioterapii Centrum Onkologii w Warszawie leczono 97 dzieci z rozpoznaniem ziarnicy złośliwej, w wieku od 2 do 18 lat. Ponad połowa pacjentów (58%) była powyżej 10 roku życia. Obserwowano znaczną przewagę chłopców M.:F = 1,77. Przeważali pacjenci w I i w II stopniu zaawansowania klinicznego (63%) i bez objawów ogólnych (62%). W rozpoznaniu histopatologicznym najczęstsza była postać NS (50%) i MC (31%).Wszystkie dzieci otrzymały leczenie chemiczne przed napromienianiem. U 71 zastosowano program B-POPA, u 18 COPP/OPPA, u pozostałych 9 inne schematy leczenia. Pacjenci byli napromieniani na teren pierwotnie zajętych okolic węzłowych, promieniami telekobaltu-60. Stosowano dawki od 20 do 36 Gy, przeważnie 25 Gy (u 65%).Obecnie żyje 91 pacjentów, zmarło jedno dziecko, 5 stracono z obserwacji. Osiemdziesięciu pacjentówzyje żyje bez nawrotu choroby. U żadnego z pozostających w obserwacji dzieci nie stwierdzono póżnych powikłań po napromienianiu

An examination of maximum legal application rates of dairy processing and associated STRUBIAS fertilising products in agriculture

peer-reviewedThe dairy industry produces vast quantities of dairy processing sludge (DPS), which can be processed further to develop second generation products such as struvite, biochars and ashes (collectively known as STRUBIAS). These bio-based fertilizers have heterogeneous nutrient and metal contents, resulting in a range of possible application rates. To avoid nutrient losses to water or bioaccumulation of metals in soil or crops, it is important that rates applied to land are safe and adhere to the maximum legal application rates similar to inorganic fertilizers. This study collected and analysed nutrient and metal content of all major DPS (n = 84) and DPS-derived STRUBIAS products (n = 10), and created an application calculator in MS Excel™ to provide guidance on maximum legal application rates for ryegrass and spring wheat across plant available phosphorus (P) deficient soil to P-excess soil. The sample analysis showed that raw DPS and DPS-derived STRUBIAS have high P contents ranging from 10.1 to 122 g kg− 1. Nitrogen (N) in DPS was high, whereas N concentration decreased in thermo-chemical STRUBIAS products (chars and ash) due to the high temperatures used in their formation. The heavy metal content of DPS and DPS-derived STRUBIAS was significantly lower than the EU imposed limits. Using the calculator, application rates of DPS and DPS-derived STRUBIAS materials (dry weight) ranged from 0 to 4.0 tonnes ha− 1 y− 1 for ryegrass and 0–4.5 tonnes ha− 1 y− 1 for spring wheat. The estimated heavy metal ingestion to soil annually by the application of the DPS and DPS-derived STRUBIAS products was lower than the EU guideline on soil metal accumulation. The calculator is adaptable for any bio-based fertilizer, soil and crop type, and future work should continue to characterise and incorporate new DPS and DPS-derived STRUBIAS products into the database presented in this paper. In addition, safe application rates pertaining to other regulated pollutants or emerging contaminants that may be identified in these products should be included. The fertilizer replacement value of these products, taken from long-term field studies, should be factored into application rates

Lignite biodegradation under conditions of acidic molasses fermentation

Lignite is difficult to degrade, thus stimulation of the autochthonous lignite microflora and introduction of additional microorganisms are required for lignite decomposition. Here, a packed bed reactor, filled with lignite samples from the Konin region (central Poland) was supplied continuously with M9 medium, supplemented with molasses (a by-product from the sugar industry), for 124 days to stimulate the autochthonous lignite microflora. Acidic fermentation of molasses was observed in the bioreactor. The simultaneous decomposition of lignite occurred under this acidic molasses fermentation condition. Our results show decay of free (non-bound) organic compounds during anaerobic lignite biodegradation. The concentrations of n-alkanes, n-alkanols, n-alkanoic acids, diterpenoids, triterpenoids and steroids present in non-biodegraded samples decreased significantly (some compounds to zero) during biodegradation. Interestingly, other compound classes like phenols, ketones and certain organic compounds increased. We interpret this phenomenon as a gradual decomposition of polymers, lignin and cellulose, present in the lignite. These changes resulted from microbial activity since they were not observed in pure solutions of short-chain fatty acids. The 16SrRNA profiling of the microbial community selected in the bioreactor revealed that the dominant bacteria belonged to the Firmicutes, Actinobacteria, Proteobacteria and Bacteroidetes, furthermore representatives of 16 other phyla were also found. All the known taxa of lignocellulolytic bacteria were represented in the microbial community. Synergistic relations between bacteria fermenting molasses and bacteria degrading lignite are assumed. The results confirm lignin degradation in acidic medium by bacteria under anaerobic conditions

Methane-yielding microbial communities processing lactate-rich substrates : a piece of the anaerobic digestion puzzle

Background: Anaerobic digestion, whose final products are methane and carbon dioxide, ensures energy flow and circulation of matter in ecosystems. This naturally occurring process is used for the production of renewable energy from biomass. Lactate, a common product of acidic fermentation, is a key intermediate in anaerobic digestion of biomass in the environment and biogas plants. Effective utilization of lactate has been observed in many experimen‑tal approaches used to study anaerobic digestion. Interestingly, anaerobic lactate oxidation and lactate oxidizers as a physiological group in methane‑yielding microbial communities have not received enough attention in the context of the acetogenic step of anaerobic digestion. This study focuses on metabolic transformation of lactate during the acetogenic and methanogenic steps of anaerobic digestion in methane‑yielding bioreactors.Results: Methane‑yielding microbial communities instead of pure cultures of acetate producers were used to process artificial lactate‑rich media to methane and carbon dioxide in up‑flow anaerobic sludge blanket reactors. The media imitated the mixture of acidic products found in anaerobic environments/digesters where lactate fermentation dominates in acidogenesis. Effective utilization of lactate and biogas production was observed. 16S rRNA profiling was used to examine the selected methane‑yielding communities. Among Archaea present in the bioreactors, the order Methanosarcinales predominated. The acetoclastic pathway of methane formation was further confirmed by analysis of the stable carbon isotope composition of methane and carbon dioxide. The domain Bacteria was represented by Bacteroidetes, Firmicutes, Proteobacteria, Synergistetes, Actinobacteria, Spirochaetes, Tenericutes, Caldithrix, Verrucomicro-bia, Thermotogae, Chloroflexi, Nitrospirae, and Cyanobacteria. Available genome sequences of species and/or genera identified in the microbial communities were searched for genes encoding the lactate‑oxidizing metabolic machinery homologous to those of Acetobacterium woodii and Desulfovibrio vulgaris. Furthermore, genes for enzymes of the reductive acetyl‑CoA pathway were present in the microbial communities.Conclusions: The results indicate that lactate is oxidized mainly to acetate during the acetogenic step of AD and this comprises the acetotrophic pathway of methanogenesis. The genes for lactate utilization under anaerobic conditions are widespread in the domain Bacteria. Lactate oxidation to the substrates for methanogens is the most energetically attractive process in comparison to butyrate, propionate, or ethanol oxidation