Biorefinery Zeitz of the Südzucker Group – Status Quo and Future Perspectives

Due to the long history of the Südzucker Group in sugar production, the company owns key know-how in processing biomass. In the last decades, the product portfolio was extended from sugar to various products such as ethanol, starch, proteins, or glucose syrups. This article presents Zeitz as the largest production site of the Südzucker Group today. The historical development is described and the synergies between the different units from which the location benefits today as a highly integrated site. Recent R&D activities are presented, and existing technologies are discussed as future perspectives to further develop Zeitz.     

Fermentative Production of L‐Lysine‐L‐lactate with Fractionated Press Juices from the Green Biorefinery

Lactic acid (LA) is a platform chemical for a future bio‐based economy. Aminium lactates act as intermediates for the production of lactic acid sequence products like lactide. It could be demonstrated that, after separation of proteins from alfalfa press juice, the supernatant can be used as fermentation media for the production of the aminium lactate, L‐lysine‐L‐lactate.     

Effektive Stofftrennung in Gas‐ und Flüssigphase durch selektive Adsorption

Adsorption is a versatile tool for the separation of low abundant molecules from complex mixtures. The affinity and selectivity of the adsorbents are crucial parameters for the efficiency of the separation process. This work provides an overview of the basic adsorption mechanisms and illustrates their relevance for technical applications based on own experimental data in bioprocess, environmental and safety engineering. Distinctive features between the adsorption from the gas and fluid phase, respectively, the differences between small molecules and interacting biomacromolecules are presented.     

Effect of pH on Aerobic Granulation and Treatment Performance in Sequencing Batch Reactors

Two sequencing batch reactors were operated to investigate the effect of influent alkalinity and reactor pH on aerobic granulation. In the first reactor R1 with high influent alkalinity the pH was adjusted in the neutral range, and in the second reactor R2 with low alkalinity the pH was held within the acidic range. The R1‐dominating species were bacteria and the appearance time of granules was three weeks after reactor start‐up. On the other hand, the acidic environment of R2 provided favorable conditions for fungal growth, and rapid granule formation occurred within the first week of operation. The varying microbial structure of granules resulted in different reactor performance in terms of evolution time and morphology of granules, suspended solids in the reactors, settling ability of granules, effluent quality of treated wastewater, and physical strength of the granules.     

Parallel Biomolecular Computation: Models and Simulations

This paper is concerned with the development of techniques for massively parallel computation at the molecular scale, which we refer to as molecular parallelism. While this may at first appear to be purely science fiction, Adleman [Ad1] has already employed molecular parallelism in the solution of the Hamiltonian path problem, and successfully tested his techniques in a lab experiment on DNA for a small graph. Lipton [L] showed that finding the satisfying inputs to a Boolean expression of size n can be done in O(n) lab steps using DNA of length O(n log n) base pairs. This recent work by Adleman and Lipton in molecular parallelism considered only the solution of NP search problems, and provided no way of quickly executing lengthy computations by purely molecular means; the number of lab steps depended linearly on the size of the simulated expression. See [Re3] for further recent work on molecular parallelism and see [Re4] for an extensive survey of molecular parallelism. Our goal is to execute lengthy computations quickly by the use of molecular parallelism. We wish to execute these biomolecular computations using short DNA strands by more or less conventional biotechnology engineering techniques within a small number of lab steps. This paper describes techniques for achieving this goal, in the context of well defined abstract models of biomolecular computation. Although our results are of theoretical consequence only, due to the large amount of molecular parallelism (i.e., large test tube volume) required , we believe that our theoretical models and results may be a basis for more practical later work, just as was done in the area of parallel computing. We propose two abstract models of biomolecular computation. The first, the Parallel Associative Memory (PAM) model, is a very high-level model which includes a Parallel Associative Matching (PA-Match) operation, that appears to improve the power of molecular parallelism beyond the operations previously considered by Lipton [L]. We give some simulations of conventional sequential and parallel computational models by our PAM model. Each of the simulations use strings of length O(s) over an alphabet of size O(s) (which correspond to DNA of length O(s log s) base pairs). Using O(s log s) PAM operations that are not PA-Match (or O(s) operations assuming a ligation operation) and t PA-Match operations, we can: 1. simulate a nondeterministic Turing Machine computation with space bound s and time bound 2 ^O(s) , with t = O(s) , 2. simulate a CREW PRAM with time bound D, with M memory cells, and processor bound P, where here s = O( log (PM)) and t = O(D+s), 3. find the satisfying inputs to a Boolean circuit constructible in s space with n inputs, unbounded fan-out, and depth D, where here t = O(D+s). We also propose a Recombinant DNA (RDNA) model which is a low-level model that allows operations that are abstractions of very well understood recombinant DNA operations and provides a representation, which we call the complex , for the relevant structural properties of DNA. The PA-Match operation for lengthy strings of length s cannot be feasibly implemented by recombinant DNA techniques directly by a single step of complementary pairing in DNA; nevertheless we show this Matching operation can be simulated in the RDNA model with O(s) slowdown by multiple steps of complementary pairing of substrings of length 2 (corresponding to logarithmic length DNA subsequences). Each of the other operations of the PAM model can be executed in our RDNA model, without slowdown. We further show that, with a further O(s)/ log (1/ε) slowdown, the simulations can be done correctly with probability 1/2 even if certain recombinant DNA operations (e.g., Separation) can error with a probability ε. We also observe efficient simulations can be done by PRAMs and thus Turing Machines of our molecular models. Received December 30, 1995; revised December 30, 1996, and January 22, 1998.     

Alternative DNA amplification methods to PCR and their application in GMO detection: a review

Nucleic acids, especially DNA, are targets of qualitative and quantitative diagnostics for genetically modified organisms (GMO) in seeds, food- and feedstuff. The amplification of the nucleic acid is an essential step for further analyses of the target sequence. The PCR has been the method of choice for DNA amplification in most laboratories, and its real-time version (qPCR) also enables quantitative analysis of target contents. Despite its numerous advantages, PCR technology has some limitations such as the lack of true multiplexing properties. To alleviate the drawbacks linked to PCR technology, alternative nucleic acid amplification methods with promising characteristics are being developed fast. These methods, their advantages, and the inconveniences, which are not yet resolved are summarized in the paper. Special focus is given to the possibilities of using these alternative methods for GMO detection in future, when expansion of GMOs both in diversity and frequencies will make current GMO detection systems difficult to operate.     

Characterization of Feed Properties for Conceptual Process Design Involving Complex Mixtures

The market for products made by biotechnology is diverse and has significantly grown in recent years. Despite this growing demand, the first proposal of product purification processes for these complex mixtures remains purely experimentally based and is not methodically targeted. The present work represents an initial study to demonstrate the benefits of a systematic approach. The study focuses on the adaptation of established methods for process development to these so‐called complex mixtures. It also assesses the suitability of these methods for complex mixtures, given the current state of research. Based on the described adaption, the most efficient method for the conceptual process development is identified and is subsequently developed. The resulting methodology consists of model‐based cost accounting with a miniaturized experimental determination of model parameters, accompanied by a comprehensive error analysis. The developed approaches are successfully validated by using a protein mixture.     

生物工程与油脂工业

本文综合论述了国外近十年来生物工程在油脂加工的应用和前景，这对我国油脂生物精炼、酶促水解、生物脂交换以及生物合成特殊脂肪酸油脂，发酵法生产甘油等研究工作具有一定指导意义。     

Fostering SME's co-development of innovative projects in biotech clusters: Extending the sets of enablers for the knowledge creation process

We explore the linkage of specific sets of enablers for the knowledge-creation process (KCP) mobilized in innovative projects co-developed by biotech SMEs and the role of industrial clusters in easing the access to enablers. Two French and one Brazilian high-tech SMEs belonging to two biotechnological clusters were investigated. Deductive and inductive approaches were applied in a complementary manner. Findings revealed a larger set of enablers at the company's level than predicted in the literature. We identified two sets of KCP enablers at the cluster's level, classified as open access and restricted access, which are used for different purposes and simultaneously. These dynamics enabled the studied SMEs to improve their co-developed innovative projects in a more effective way. Data also revealed that the enablers that benefit SMEs are more likely provided by the cluster organisations.     

沼气生物脱硫技术监控系统

以往沼气脱硫大多采用物理、化学法,这种方法存在能耗高、处理费用昂贵等不足,为此提出了沼气生物脱硫技术监控系统.系统采用西门子S7-300系列PLC,实现数据记录、调节、参数修改和实时控制;同时,通过VPN技术与企业生产管理实现远程实时监控.多个项目的现场实践应用表明,该系统现场设备运行稳定、维护调试方便,为目前逐步推广的生物沼气脱硫技术提供了借鉴.