Search

The method of E.V. Borutski was used for determining the production of chironomids, that is, the dynamics of the number and biomass of the larvae were analysed, their death, a calculation of emergence and the number of deposited egg layings was carried out. In addition to the method of Borutski, the authors also calculated the seasonal dynamics of the number of larvae of the younger age stages in the microbenthos. Translated from Russian into English

SUMMARY Enzymes are large proteins present in all living organisms (plants, animals, microorganisms). Enzymes play important roles in food and beverage industry and have already been recognized as valuable catalysts for o rganic transformations and production of fine chemicals and pharmaceuticals. Enzymatic methods have already replaced some conventional chemical processes. Biocatalytic route s in combination with chemical synthesis are finding increased use in the synthesis of novel polymeric materials. The discovery of new and improved enzymes and their use in various processes and products will create new market opportunities for enzymes and solve environmental problems. At present, the most commonly used enzymes in biotechnology are hydrolytic ones which catalyze the breakdown of larger biopolymers into smaller units. Such enzymes cataly ze hydrolytic reactions in a selective manner, not only regio- but also stereoselectively and have been used both for asymmetric synthesis and racemic resolutions. Pectinases (P) or pectinolytic enzymes catalyze the degradation of pectinic substances. The biotechnolo gical potential of pectinolytic enzymes from microorganisms has drawn a great deal of atten tion for use as biocatalysts in industrial processes, but also their main role in the extract ion and clarification of fruit juices is well established, pretreatment of pectic wastewater, cof fee and tea fermentation. Cellulases (C) catalyze the hydrolysis of the β-1, 4 linkages, acting as glucoside hydrolases. Cellulases are curently the third large st industrial enzymes, used mainly in cotton processing, but also in paper recycling, as deterge nt enzymes, in juice extraction and as animal feed aditives. However, cellulases will beco me the largest volume industrial enzyme, if ethanol, butanol, or some other fermentation pro duct of sugars, produced from biomass, becomes a major transportation fuel, as seems likel y. Hemicellulases (HC) catalyze the degradation of hemicelluloses, found in many fruits , with many applications in industrial processes. Hemicellulases are routinely used for th e improvement of animal feed, in the pulp and paper industry for biobleaching and biopulping, and for processing flour in the bakery. The most challenging application is the development of an economic process for the solubilization of lignocellulose material to serve as a carbon source for renewable energy. We review here the main applications of these enzymes in improving food/agriculture waste resource management (valorization of apple residues , sugarbeet, wood) and some preliminary results on the (UV-VIS, FTIR) spectroscopy investigation of P, C, HC activity and efficiency on apple skin substrate.

1. The choice of a paraffin-containing petroleum raw material for the production of feed protein is governed by the cost of the n-paraffins contained in the petroleum product and the costs involved in obtaining products of the required quality from these raw materials. 2. In the current five-year period, for the production of feed yeast, the starting material will consist of purified liquid waxes in the form of a light fraction with a boiling range of 280–320°C, obtained by distilling a wax fraction that has been recovered and purified in existing units. 3. The utilization of liquid waxes differing in degree of purity for the production of feed yeast will be profitable in all cases; however, as shown by preliminary calculations, it will be less favorable than the use of petroleum distillates if the cost of commercial waxes exceeds the cost of the n-paraffinic hydrocarbons in the petroleum distillates plus the costs for extractive treatment of the biomass grown on this material. 4. Petroleum distillates are promising raw material for the development of large-scale production of feed protein.

Direct and indirect methods of the assessment of growth rate (productivity) in hydrocarbon fermentation are briefly reviewed. The application of an indirect method, based on alkali consumption at constant pH, is discussed from the viewpoint of varying protein content in the biomass dry weight. An automatic control of substrate addition based on the indirect method is suggested.

The most common renewable fuel today is ethanol derived from corn grain (starch) and sugar cane (sucrose). It is expected that there will be limits to the supply of these raw materials in the near future as well as these are directly associated with food security. Therefore, lignocellulosic biomass is seen as an attractive alternative feedstock for the future supplies of bioethanol. Technologies are being developed that will allow cost-effective conversion of biomass into fuels and chemicals. About 491 GL of bioethanol might be produced from the wasted crops and their associated lignocellulosic raw materials, about 16 times higher than the current world ethanol production (31 GL). Key words: Bioethanol; Lignocellulosic material; Biofuel; Agricultural residue. DOI: 10.3126/sw.v6i6.2628 Scientific World, Vol. 6, No. 6, July 2008 19-23

Anaerobically pretreated sewage was treated by an aerobic bacterial disc unit. Owing to the plug-flow nature of the system, different microfloral populations developed on the different discs. The maximum weight of biomass obtained was 45 g m -2 of the wetted surface. Maximum COD removal was 0·49 g COD g -1 biomass day -1 . Practically all nitrogen was converted to nitrate; maximum nitrification rate was 0·138 g NO 3 –N g -1 biomass day -1 .

A micromanipulation technique was employed for the single cell isolation of microorganisms from 51 washed activated sludge and trickling filter zoogloeas. Only 203 of the isolated organisms were successfully recovered as viable cultures. Fifty-six isolates were nonzoogloeal and found both in branched and unbranced zoogloeas. The nonzoogloeal bacteria were generally biochemically active. Branched zoogloeas visibly formed a minor portion of the biomass of trickling filters and activated sludge whereas amorphous zoogloeas were present in large proportions. The biochemical diversity of bacteria present in amorphous zoogloeas may be an indication that these zoogloeas are important in wastewater treatment.

Continuous cultivation of the yeast Candida lipolytica on gas oil was studied from the viewpoint of biomass production and oil deparaffination. Optimum conditions wore found at the dilution rate D = 0.16–0.19 when biomass productivity 1.7 g/l/hr and yield coefficient. y = 0.92 were achieved. At deparaffination to the same freezing point, more than double the production of biomass and deparaffined oil during a given time unit was achieved in a continuous process than in batch cultivation. Consumption of substrate was followed in both cultivation processes and it was confirmed that individual n-alkanes of gas oil were degraded at various rates and yields. Results proved optimum cultivation conditions to depend on concentration and composition of the paraffinic fraction of gas oil used. To achieve these conditions the continuous process may be controlled by choice; of suitable dilution rate and concentration of gas oil.

Nyamplung shell is a biomass whose existence has not been optimally utilized. Biomass is a solid waste that can be used again as a source of fuel. Favorable characteristics of the biomass is an energy source that can be utilized in a sustainable manner because it is renewable. Biomass of Nyamplung shell can be processed become a form of solid fuel with a same specific dimension, it is resulting from compression of bulk materials, powders, and the relatively small size commonly referred to as charcoal briquettes. The aim of this research is to test the feasibility of nyamplung shell as a raw material for making briquettes on the households by conducting analysis of quality parameters briquette specimens including physical properties (water content, calor value, and density), briquette durability (persistence press), chemical (ash content, fixed carbon and volatile matter content) and the rate of burning charcoal briquette. The treatment in this aim is a mixture composition of raw materials (charcoal of Nyamplung shell) who were given the same amount of adhesive and compressed by compressing hydraulic briquette. The results showed that, charcoal briquettes made from the Calophyllum shell can be used as alternative energy, with a characteristic range of values from 3,39-3,83% moisture content, calor value ranges from 3.646,14-5.431,35 calories / gram, the range of density values 0,663-0,721 gram/cm3, the range of persistence press value 1,98-5,39 kg/cm2, the range of ash content value 19,89-24,51%, the range of fixed carbon value 33,09-40,86%, the range of volatile matter value 35,03-38,57%, and the range of rate of burning from 0,0574-0,0898 grams/second. The low value of moisture content can lead to higher heating value of charcoal briquettes. High/low levels of volatile could affect fast/slow rate of burning charcoal briquettes. Key words : nyamplung shell, biomass, charcoal briquette

(1) Potential uses of photosynthetie bacteria in the recycling of human wastes have been considered. It is concluded that systems using photosynthetic bacteria may have advantages over purely algal systems under conditions where total recycling is needed and energy is not abundant. (2) Two systems are proposed in which the metabolic potential of the photosynthetic bacteria might be realized. Both systems include an anaerobic recycling stage in which fermented wastes are converted to biomass by bacterial photosynthesis. In one system gaseous recycling is accomplished by a secondary algal reactor acting under aerobic conditions. In the other, oxygen is regenerated by electrolysis of water, and hydrogen and carbon dioxide are assimilated autotrophically under anaerobic conditions in the same bacterial photosynthesis reactor used for anaerobic recycling. (3) Advantages and disadvantages arising from the use of photosynthetic bacteria in recycling are discussed, and some potential model systems are proposed.

Batch anaerobic dry digestion promises further application in agriculture and for treatment of municipal solid waste, especially with smaller substrate throughputs. As in other anaerobic systems, bacteriological activity is inhibited by lack of moisture and in batch dry digestion liquid is sprinkled over the substrate to encourage biomass degradation and biogas production throughout the process. Laboratory-scale experiments were carried out to investigate individual methane generation from the recirculated liquid phase and from the stacked solid material. Results clearly indicate that methane formation within the recirculated liquid significantly adds to the total methane production of the process. Up to 21% of the total methane generation originated from the recirculated liquid. This suggests that methane generation from the liquid phase is not to be neglected and needs to be recuperated. The process water tank should be equipped with gas collection facilities. Experimental results further indicate that higher ratios of easily hydrolysable substrates increase the proportion of methane from the liquid phase while slowly hydrolysable material encourages biogas generation in the decomposing biomass bed itself. While the amount of easily hydrolysable biomass in the system and the ratio of methane produced in the liquid phase could be positively correlated, no correlation was possible between the volume of liquid in the process water tank and the methane proportion originating from the liquid phase.

A conical glass V-fermenter for plant cell suspension cultures is described. This V-fermenter has proved useful for the production of biomass and metabolic products. It also is ideally suited for the preparation and maintenance of actively growing cultures to be used as inocula for shake flasks and fermenters. An outline of the procedure for isolating and "conditioning" plant cell suspension cultures is presented.

Biomass and nutrient content of natural stands of northern hardwood regeneration were measured 4 years after clearcutting. Pin cherry and shrubs made up a significant proportion of the biomass in both unfertilized and fertilized stands. Yet these stands are well stocked with large numbers of desirable commercial species, especially paper and yellow birch. However, fertilizer greatly stimulated pin cherry to the detriment of the commercial species. Paper birch was the only commercial species to increase in average dry weight on the fertilized area.

Aquatic ecosystems have the ability to compensate for oscillations of the inputs (substrate concentration, dilution rate, temperature). The mechanisms of this buffering capacity are studied in this paper (see fig. 7). The inputs exert an influence on the biomass and the activity of the organisms (activity = specific rate of RNA-synthesis or specific P-removal rate [μ/mg biomass day]). The activity is regulated either directly by the inputs and/or indirectly by the biomass. The activity decreases with an increase of the biomass (see fig. 5 and 6). The product of biomass and activity determines the transient response (= effective performance) of the system which is better buffered than biomass or activity alone. Considering the theory developed in this paper the effect of shock loadings on the phosphate removal in preimpoundment basins of drinking water reservoirs is discussed.

This paper presents a review of current trends in research in the Soviet Union on the ecology of aquatic bacteria. The paper shows an increasing emphasis on in situ measurements of the rate or extent of conversion of carbon, nitrogen, sulfur, and iron from one form to another and on the bacteria responsible for these conversions. Theoretical considerations and results of several studies are summarized. These include measurement of bacterial biomass production and nitrogen fixation with isotopes, factors affecting decomposition of water humus in bog lakes, annual succession of iron bacteria in relation to the cycling of iron, nitrogen exchange between bottom sediment and benthic waters, the concept and calculation of nitrogen balance in a lake, and the bacteria responsible for the oxidation of sulfur. An attempt is made to incorporate this information into flow diagrams showing the dynamics of the cycling of the four elements discussed.