Tackling Ischemic Reperfusion Injury With the Aid of Stem Cells and Tissue Engineering

Ischemia is a severe condition in which blood supply, including oxygen (O), to organs and tissues is interrupted and reduced. This is usually due to a clog or blockage in the arteries that feed the affected organ. Reinstatement of blood flow is essential to salvage ischemic tissues, restoring O, and nutrient supply. However, reperfusion itself may lead to major adverse consequences. Ischemia-reperfusion injury is often prompted by the local and systemic inflammatory reaction, as well as oxidative stress, and contributes to organ and tissue damage. In addition, the duration and consecutive ischemia-reperfusion cycles are related to the severity of the damage and could lead to chronic wounds. Clinical pathophysiological conditions associated with reperfusion events, including stroke, myocardial infarction, wounds, lung, renal, liver, and intestinal damage or failure, are concomitant in due process with a disability, morbidity, and mortality. Consequently, preventive or palliative therapies for this injury are in demand. Tissue engineering offers a promising toolset to tackle ischemia-reperfusion injuries. It devises tissue-mimetics by using the following: (1) the unique therapeutic features of stem cells, i.e., self-renewal, differentiability, anti-inflammatory, and immunosuppressants effects; (2) growth factors to drive cell growth, and development; (3) functional biomaterials, to provide defined microarchitecture for cell-cell interactions; (4) bioprocess design tools to emulate the macroscopic environment that interacts with tissues. This strategy allows the production of cell therapeutics capable of addressing ischemia-reperfusion injury (IRI). In addition, it allows the development of physiological-tissue-mimetics to study this condition or to assess the effect of drugs. Thus, it provides a sound platform for a better understanding of the reperfusion condition. This review article presents a synopsis and discusses tissue engineering applications available to treat various types of ischemia-reperfusions, ultimately aiming to highlight possible therapies and to bring closer the gap between preclinical and clinical settings.

CURRICULUM RENEWAL FOR BETTER DESIGN-RELATED STUDENT OUTCOMES IN SECOND-YEAR CHEMICAL AND BIOLOGICAL ENGINEERING

The Department of Chemical and Biological Engineering at UBC is currently undergoing a majorcurriculum renewal with the aim of modernizing the two undergraduate programs it offers to better prepare students for increasingly diverse industries. Part of this initiative aims to introduce design earlier and integrate it throughout the programs. At the core of the new 2nd year curriculum are two new cornerstone courses: CHBE 220 and 221 – Fundamentals of Chemical and Biological Engineering I/II. CHBE 220 is taken in term 1 and replaces a previous classicallystructuredphysical chemistry course and an introductory seminar on process technology. It focuses on basicchemical process design and analysis, drawing from thermodynamics and kinetics as needed to support design topics. CHBE 221, offered in term 2, replaces a previous introductory cell biology course, and focuses on industrial microbiology and bioprocess design, drawing from cell and molecular biology and physical chemistry as needed to support design tasks. Both courses include substantial term-spanning design projects. This paper outlines the content and structure of bothcourses and their place in the updated curriculum. It describes the integrated design projects and other course deliverables. Recommendations for future iterations of the courses are also presented.

Bioreactor and Bioprocess Design Issues in Enzymatic Hydrolysis of Lignocellulosic Biomass

Saccharification of lignocellulosic biomass is a fundamental step in the biorefinery of second generation feedstock. The physicochemical and enzymatic processes for the depolymerization of biomass into simple sugars has been achieved through numerous studies in several disciplines. The present review discusses the development of technologies for enzymatic saccharification in industrial processes. The kinetics of cellulolytic enzymes involved in polysaccharide hydrolysis has been discussed as the starting point for the design of the most promising bioreactor configurations. The main process configurations—proposed so far—for biomass saccharification have been analyzed. Attention was paid to bioreactor configurations, operating modes and possible integrations of this operation within the biorefinery. The focus is on minimizing the effects of product inhibition on enzymes, maximizing yields and concentration of sugars in the hydrolysate, and reducing the impact of enzyme cost on the whole process. The last part of the review is focused on an emerging process based on the catalytic action of laccase applied to lignin depolymerization as an alternative to the consolidated physicochemical pretreatments. The laccases-based oxidative process has been discussed in terms of characteristics that can affect the development of a bioreactor unit where laccases or a laccase-mediator system can be used for biomass delignification.

Statistical Based Bioprocess Design for Improved Production of Amylase from Halophilic Bacillus sp. H7 Isolated from Marine Water

Amylase (EC 3.2.1.1) enzyme has gained tremendous demand in various industries, including wastewater treatment, bioremediation and nano-biotechnology. This compels the availability of enzyme in greater yields that can be achieved by employing potential amylase-producing cultures and statistical optimization. The use of Plackett–Burman design (PBD) that evaluates various medium components and having two-level factorial designs help to determine the factor and its level to increase the yield of product. In the present work, we are reporting the screening of amylase-producing marine bacterial strain identified as Bacillus sp. H7 by 16S rRNA. The use of two-stage statistical optimization, i.e., PBD and response surface methodology (RSM), using central composite design (CCD) further improved the production of amylase. A 1.31-fold increase in amylase production was evident using a 5.0 L laboratory-scale bioreactor. Statistical optimization gives the exact idea of variables that influence the production of enzymes, and hence, the statistical approach offers the best way to optimize the bioprocess. The high catalytic efficiency (kcat/Km) of amylase from Bacillus sp. H7 on soluble starch was estimated to be 13.73 mL/s/mg.

Butanol production from lignocellulosic sugars by Clostridium beijerinckii in microbioreactors

Background Butanol (n-butanol) has been gaining attention as a renewable energy carrier and an alternative biofuel with superior properties to the most widely used ethanol. We performed 48 anaerobic fermentations simultaneously with glucose and xylose as representative lignocellulosic sugars by Clostridium beijerinckii NCIMB 8052 in BioLector® microbioreactors to understand the effect of different sugar mixtures on fermentation and to demonstrate the applicability of the micro-cultivation system for high-throughput anaerobic cultivation studies. We then compared the results to those of similar cultures in serum flasks to provide insight into different setups and measurement methods. Results ANOVA results showed that the glucose-to-xylose ratio affects both growth and production due to Carbon Catabolite Repression. The study demonstrated successful use of BioLector® system for the first time for screening several media and sugar compositions under anaerobic conditions by using online monitoring of cell mass and pH in real-time and at unprecedented time-resolution. Fermentation products possibly interfered with dissolved oxygen (DO) measurements, which require a careful interpretation of DO monitoring results. Conclusions The statistical approach to evaluate the microbioreactor setup, and information obtained in this study will support further research in bioreactor and bioprocess design, which are very important aspects of industrial fermentations of lignocellulosic biomass.

Plant-Wide Systems Microbiology for the Wastewater Industry

The wastewater treatment sector embraces mixed-culture biotechnologies for sanitation, environmental protection, and resource recovery. Bioprocess design, monitoring and control thrive on microbial processes selected in complex microbial communities. Microbial ecology...

CURRICULUM RENEWAL FOR BETTER DESIGN-RELATED STUDENT OUTCOMES IN SECOND-YEAR CHEMICAL AND BIOLOGICAL ENGINEERING

The Department of Chemical and Biological Engineering at UBC is currently undergoing a major curriculum renewal with the aim of modernizing the two undergraduate programs it offers to better prepare students for increasingly diverse industries. Part of this initiative aims to introduce design earlier and integrate it throughout the programs. At the core of the new 2nd year curriculum are two new courses: CHBE 220 and 221 – Fundamentals of Chemical and Biological Engineering I/II. CHBE 220 is taken in term 1 and replaces a previous classically-structured physical chemistry course and an introductory seminar on process technology. It focuses on basic chemical process design and analysis, drawing from thermodynamics and kinetics as needed to support design topics. CHBE 221, offered in term 2, replaces the previous introductory cell biology course, and focuses on industrial microbiology and bioprocess design, drawing from cell and molecular biology and physical chemistry as needed to support design tasks. Both courses include substantial term-spanning design projects. This paper outlines the content and structure of both courses and their place in the updated curriculum. It describes the integrated design projects and other course deliverables. Recommendations for future iterations of the courses are also presented.

Butanol Production from Lignocellulosic Sugars by Clostridium beijerinckii in Microbioreactors

Background: Butanol ( n- butanol) has been gaining attention as a renewable energy carrier and an alternative biofuel with superior properties to the most widely used ethanol. We performed 48 anaerobic fermentations simultaneously with glucose and xylose as representative lignocellulosic sugars by Clostridium beijerinckii NCIMB 8052 in BioLector® microbioreactors to understand the effect of different sugar mixtures on fermentation and to demonstrate the applicability of the micro-cultivation system for high-throughput anaerobic cultivation studies. We then compared the results to those of similar cultures in serum flasks to provide insight into scalability.Results: ANOVA results showed that the glucose to xylose ratio affects both growth and production due to Carbon Catabolite Repression . The study showed that the BioLector® system is well suited for screening several media and sugar compositions under anaerobic conditions.Conclusions: The approach of, and information obtained in this study will support further research in bioreactor and bioprocess design and scale-up that are very important aspects of industrial fermentations of lignocellulosic biomass.