Software sensors for biomass concentration estimation in filamentous microorganism cultivation process

In this study, the potential of two software sensors for on-line estimation of biomass concentration during cultivation of filamentous microorganisms is examined. The first sensor is based on common bioreactor off-gas analyses, and uses the assumption of the biomass concentration linear dependence on the square root of cumulative O-2, consumption. Parameters of the semi-empirical data-driven software sensor based on off-gas analysis were calculated from experimental cultivation data using linear regression. The second sensor is based on biocalorimetry, i.e., the on-line calculation of metabolic heat flux from general enthalpy balance of the bioreactor. The software sensor based on biocalorimetry thus essentially represents a model-driven approach, making use of a fundamental process model based on the enthalpy balance around the bioreactor. This approach has been combined with the experimental identification of the specific biomass heat production, which represents the main process-specific parameter of the software sensor based on biocalorimetry. For this sensor, the accuracy requirements on the process variable on-line measurements were also analysed. The experimental data from the pilot-scale antibiotics Nystatin production by a bacterium Streptomyces noursei were used to calculate the specific bioprocess heat production value using linear regression. The achieved results enabled us to propose a new on-line indicator calculated as the ratio of the outputs of both sensors, which can serve as a timely warning of the risk of undesired nutritional conditions of a culture characterized as underfeeding.Technology Agency of the Czech Republic [TA03010165

Monitoring of Biopolymer Production Process Using Soft Sensors Based on Off-Gas Composition Analysis and Capacitance Measurement

This paper focuses on the design of soft sensors for on-line monitoring of the biotechnological process of biopolymer production, in which biopolymers are accumulated in bacteria as an intracellular energy storage material. The proposed soft sensors for on-line estimation of the biopolymer concentration represent an interesting alternative to the traditional off-line analytical techniques of limited applicability for real-time process control. Due to the complexity of biochemical reactions, which make it difficult to create reasonably complex first-principle mathematical models, a data-driven approach to the design of soft sensors has been chosen in the presented study. Thus, regression methods were used in this design, including multivariate statistical methods (PLS, PCR). This approach enabled the creation of soft sensors using historical process data from fed-batch cultivations of the Pseudomonas putida KT2442 strain used for the production of medium-chain-length polyhydroxyalkanoates (mcl-PHAs). Specifically, data from on-line measurements of off-gas composition analysis and culture medium capacitance were used as input to the soft sensors. The resulting soft sensors allow not only on-line estimation of the biopolymer concentration, but also the concentration of the cell biomass of the production bacterial culture. For most of these soft sensors, the estimation error did not exceed 5% of the measurement range. In addition, soft sensors based on capacitance measurement were able to accurately detect the end of the production phase. This study thus offers an innovative and practically relevant contribution to the field of monitoring of bioprocesses used for the production of medium-chain-length biopolymers

Vznik mobilního lehkého polního dělostřelectva během třicetileté války

This paper gives an overview of the emergence and development of mobile light fi eld artillery in selected European countries during the fi rst half of the Thirty Years’ War. In the fi nal part of the paper, the importance of the collection of four fi eld bronze cannons from the period of the Thirty Years’ War at the Opočno Castle in East Bohemia is also discussed

Assessing aerobic biodegradability of plastics in aqueous environment by GC-analyzing composition of equilibrium gaseous phase

Byl zpracován matematický model acidobazické rovnováhy CO2 v systému plyn - kapalina umožňující stanovit množství produkovaného CO2 chromatografickou analýzou plynné fáze. Za vytipovaných podmínek byla sledována biologická rozložitelnost modelových vzorků, průběh biorozkladu byl sledován podle produkce CO2 stanovované GC analýzou plynné fáze a standardním "titračním" postupem. Jedná se o "zastupitelné" postupy sledování průběhu aerobního biologického rozkladu látek ve vodním prostředí.A mathematical model of acid-basic CO2 equilibrium in a gas - liquid system was worked out, enabling to determine quantity of produced CO2 through chromatographic analysis of gaseous phase. Under appropriate test conditions, biodegradability of model samples was explored. Course of biodegradation was studied through produced CO2 determined by analyzing gaseous phase through GC on the one hand, and through customary "titration" procedure on the other. The procedures in question are "substituting" procedures for observing course of aerobic biodegradation of substances in an aqueous environment

Assessing aerobic biodegradability in aqueous environment by analyzing composition of equilibrium gaseous phase

Cílem práce bylo posouzení možnosti využití plynově chromatografické analýzy plynné fáze pro hodnocení aerobní biologické rozložitelnosti látek ve dvoufázovém systému plyn-kapalina. Příspěvek je rozdělen do dvou částí: v první části je diskutována acidobazická rovnováha CO2 v reálných podmínkách biologických testů; druhá část příspěvku pak zahrnuje experimentální ověření teoretických závěrů bilance CO2.The objective of this study was to verify potential use of chromatographic analysis of gaseous phase composition in an enclosed two-phase gas-liquid system to study course of biodegradation. This contribution is divided into the two parts: in the first part acidobasic equilibrium states of CO2 in a real biological system is discussed; the second part of this contribution includes experimental verification of the theoretical conclusions

Decelerating weight loss of harvested strawberries by applying edible coatings based on starch-protein hydrolysate of amaranth flour

Cílem práce bylo sledování kvalitativních změn sklizených jahod opatřených ochranným jedlým polymerním povlakem. Povlaky byly vytvořeny máčením jahod do škrobo-proteinového hydrolysátu amarantové mouky o koncentraci 50 % (w/w). Testoval se vliv přídavku změkčovadla ? glycerinu (10 a 30 %) a síťovadla ? dialdehydu škrobu (1 a 4 %) na bariérové vlastnosti povlaků. Tenký ochranný film byl na jahodách vytvořen po 5 min sušení v sušárně; testovaly se teploty 23, 30 a 40 oC. Jahody byly skladovány při teplotách 7?1,5 oC (relativní vlhkost 40?3 %) a 23?1,5 oC (relativní vlhkost 48?2 %). Sledoval se hmotnostní úbytek jahod. Výsledky ukázaly, že ochranný polymerní povlak vytvořený z 50 % roztoku hydrolysátu amarantové mouky s přídavkem 30 % glycerinu má optimální bariérové vlastnosti pro vodní páry. U jahod ošetřených tímto povlakem byly zaznamenány nejnižší hmotnostní ztráty způsobené odpařováním vlhkosti při obou skladovacích teplotách.The work studied weight losses of harvested strawberries provided with protective edible coating. Coatings were produced by dipping strawberries in 50 % (w/w) starch-protein hydrolysate of amaranth flour. Tests investigated influence of added glycerol (10 or 30 %) and dialdehyde starch (1 or 4 %) on barrier properties. A protective film was produced on the strawberries after drying 5 min at 23, 30 or 40 oC. Strawberries were stored at 7?1.5 oC or 23?1.5 oC. The lowest losses in mass caused by humidity evaporating were provided by a protective coating produced with 30 % added glycerol at both storage temperatures.Ministry of Education of The Czech Republic under MSM [7088352102

Digital image analysis for morphological state characterization of a culture of filamentous microorganisms in production of antibiotics

The paper deals with the application of specific methods of digital image analysis for the monitoring of morphological changes in cultures of filamentous microorganisms. First, a sequence of digital image preprocessing and processing steps is proposed for the treatment of microscopic images of a filamentous culture. The preprocessing step include band pass filtering by the Difference of Gaussians filter featuring a novel approach to the task of parameters tuning, as well as the optimization of image porosity and image objects separation quality. In the processing step, the resulting enhanced images are subject to morphological state characterization using a set of several standard and modified morphological parameters. Descriptions of morphological states of different complexity are then discussed varying from the standard set of mean values of parameters to the set of parameters in their full histogram of value frequencies (distribution) form. For such complex descriptions also new fashions of graphical representation of results without loss of information are compared. The potential of the proposed full description of morphological behavior of the culture is demonstrated using a set of microscopic images taken during an industrial antibiotics production cultivation using a microorganism belonging into the Streptomyces genus. Finally, the cluster analysis is proposed for further automatic quantitative classification and interpretation of complex description of metabolic states.Technology Agency of the Czech Republi

Processing of Keratin Waste of Meat Industry

Chicken feathers were processed through hydrolysis in two stages and breakdown efficiency was monitored by factor tests. In the first stage, feathers were incubated in an environment of 0.1 % or 0.3 % aqueous solution of KOH (ratio 1:50) for 24 h at 70 degrees C. After adapting pH level to 9, action by proteolytic enzyme polarzyme 12 T (1-5 %, w/w) at temperature 30-50 degrees C broke down the feathers in 4-8 h into keratin hydrolyzate. Hydrolysis of feathers in environment of 0.1 % KOH is quite low (max. 20%). In an environment of 0.3 % KOH the hydrolysis efficiency is more than four-fold. At upper limits of factors under study (8 h hydrolysis at 50 degrees C with 5 % addition of enzyme) 88.7 % feathers were degraded. Test results confirmed that applying proteolytic enzyme polarzyme 12 T achieved efficiency of chicken feather degradation similar to formerly used enzyme Savinase Ultra 16 L

Solubility of edible films from amaranth flour enzymatic hydrolysate modified with dialdehyde starch

Cílem práce byla příprava biodegradabilních a jedlých filmů ze škrobo-proteinového hydrolysátu amarantové mouky a studium vlivu chemické a fysikální modifikace na rozpustnost filmů. Filmy byly připraveny litím z 25 % (w/w) roztoku hydrolysátu s přídavkem 20 % glycerinu a s různými přídavky dialdehydu škrobu (0, 1a 5 %). Po tepelné exposici filmů při 65 a 95 °C (doba 6 a 48 hodin) byly provedeny zkoušky rozpustnosti filmů ve vodě při 6 a 37 oC. Bylo zjištěno, že chemickou a fysikální modifikací filmů lze výrazně měnit jejich rozpustnost ve vodě. Výsledky zkoušek rozpustnosti filmů mohou posloužit při praktickém využití škrobo-proteinového hydrolysátu amarantové mouky k výrobě biodegradabilních obalových materiálů (filmy, fólie, mikrokapsule) v potravinářství, ve farmacii, v kosmetice či v zemědělství.The objective of the work was to prepare biodegradable and edible films based on amaranth flour starch-protein hydrolysate and evaluate the effect of chemical and physical modifications on solubility properties of films. Films were prepared by casting a 14 % (w/w) water solution of hydrolysate containing 20 % (per hydrolysate dry matter) glycerol and 0, 1 or 5 % (per hydrolysate dry matter) additions of dialdehyde starch. After thermal exposure of films at 65 or 95 oC (for 6 or 48 hours) film solubility tests were performed in water at 6 or 37 oC. It was found that chemical modification (added dialdehyde starch) and physical modification (thermal exposure) of films allows to markedly altering their water solubility. Results of water solubility tests can serve to practically utilising starch-protein hydrolysate of amaranth flour for producing biodegradable packaging materials (foils, coatings) to be employed in the food industry, cosmetics or agriculture