Immobilisation of Clostridium spp. for production of solvents and organic acids

2014 ◽  
Vol 68 (1) ◽  
pp. 1-14 ◽  
Author(s):  
Igor Dolejš ◽  
Martin Rebroš ◽  
Michal Rosenberg

AbstractThis review summarises the high potential of immobilised cells systems for the fermentative production of compounds, mainly produced by representatives of the Clostridium genus. Microorganisms of Clostridium species are recognised as good producers of a wide range of chemicals in almost every sector of industry. The combination of this microorganism with its immobilisation opens up new possibilities and renders the fermentation process more sophisticated than in a free-cell system. This review provides a comprehensive summary of techniques used in immobilisation of Clostridium species with regard to specific products and types of fermentation. In addition, comparisons of particular types of immobilisation techniques used in fermentation processes are summarised by specific products.

2021 ◽  
Vol 22 (3) ◽  
pp. 1199
Author(s):  
Elena Karnaukhova ◽  
Catherine Owczarek ◽  
Peter Schmidt ◽  
Dominik J. Schaer ◽  
Paul W. Buehler

Plasma hemopexin (HPX) is the key antioxidant protein of the endogenous clearance pathway that limits the deleterious effects of heme released from hemoglobin and myoglobin (the term “heme” is used in this article to denote both the ferrous and ferric forms). During intra-vascular hemolysis, heme partitioning to protein and lipid increases as the plasma concentration of HPX declines. Therefore, the development of HPX as a replacement therapy during high heme stress could be a relevant intervention for hemolytic disorders. A logical approach to enhance HPX yield involves recombinant production strategies from human cell lines. The present study focuses on a biophysical assessment of heme binding to recombinant human HPX (rhHPX) produced in the Expi293FTM (HEK293) cell system. In this report, we examine rhHPX in comparison with plasma HPX using a systematic analysis of protein structural and functional characteristics related to heme binding. Analysis of rhHPX by UV/Vis absorption spectroscopy, circular dichroism (CD), size-exclusion chromatography (SEC)-HPLC, and catalase-like activity demonstrated a similarity to HPX fractionated from plasma. In particular, the titration of HPX apo-protein(s) with heme was performed for the first time using a wide range of heme concentrations to model HPX–heme interactions to approximate physiological conditions (from extremely low to more than two-fold heme molar excess over the protein). The CD titration data showed an induced bisignate CD Soret band pattern typical for plasma and rhHPX versions at low heme-to-protein molar ratios and demonstrated that further titration is dependent on the amount of protein-bound heme to the extent that the arising opposite CD couplet results in a complete inversion of the observed CD pattern. The data generated in this study suggest more than one binding site in both plasma and rhHPX. Furthermore, our study provides a useful analytical platform for the detailed characterization of HPX–heme interactions and potentially novel HPX fusion constructs.


Foods ◽  
2021 ◽  
Vol 10 (6) ◽  
pp. 1377
Author(s):  
Song-Hui Soung ◽  
Sunmin Lee ◽  
Seung-Hwa Lee ◽  
Hae-Jin Kim ◽  
Na-Rae Lee ◽  
...  

Numerous varieties of doenjang are manufactured by many food companies using different ingredients and fermentation processes, and thus, the qualities such as taste and flavor are very different. Therefore, in this study, we compared many products, specifically, 19 traditional doenjang (TD) and 17 industrial doenjang (ID). Subsequently, we performed non-targeted metabolite profiling, and multivariate statistical analysis to discover distinct metabolites in two types of doenjang. Amino acids, organic acids, isoflavone aglycones, non-DDMP (2,3-dihydro-2,5-dihydroxy-6-methyl-4H-pyran-4- one) soyasaponins, hydroxyisoflavones, and biogenic amines were relatively abundant in TD. On the contrary, contents of dipeptides, lysophospholipids, isoflavone glucosides and DDMP-conjugated soyasaponin, precursors of the above-mentioned metabolites, were comparatively higher in ID. We also observed relatively higher antioxidant, protease, and β-glucosidase activities in TD. Our results may provide valuable information on doenjang to consumers and manufacturers, which can be used while selecting and developing new products.


2021 ◽  
Vol 233 ◽  
pp. 02052
Author(s):  
Chun Zou ◽  
Yongquan Xu ◽  
Jianxin Chen ◽  
Ruyi Li ◽  
Fang Wang ◽  
...  

In this study, the fermentation process of black tea wine was optimized, and the changes in catechins, organic acids, and aroma components during fermentation were investigated. The optimal fermentation conditions for tea wine were determined as follows: the addition of 15% sucrose and 0.75% tea leaves, and a fermentation temperature of 25 ºC. Under the optimal conditions, the alcohol content and sensory evaluation score of tea wine were 8.9 %ABV and 88, respectively. The contents of catechins and organic acids in tea wine were 21.29 mg/L and 3.68 mg/mL, which were 1.32-fold and 10.51-fold higher than those of tea infusion, respectively. L-malic acid was the main organic acid in tea wine, which accounted for 56.3% of the total amount of organic acids. A total number of 34 and 33 kinds of aroma components were detected in tea wine and tea infusion, respectively. The main aroma components of tea wine were esters and alcohols, which accounted for 39.7% and 45.9% of the total amount of aroma components, respectively, while the main aroma components of tea infusion were esters and aldehydes, accounting for 34.6% and 33.2%, respectively.


2021 ◽  
Author(s):  
Jelena Mladenovic ◽  
◽  
Nebojsa Markovic ◽  
Ljiljana Boskovic-Rakocevic ◽  
Milena Đuric ◽  
...  

Sempervivum tectorum has a similar effect as aloe vera, which is known in the treatment of various skin diseases. This herb is considered one of the safest remedies for a wide range of skin diseases. Due to its anti-inflammatory and antiseptic properties, it also serves as an excellent first aid for burns, stings and bites, because it provides quick relief and calming. Freshly squeezed juice from the leaves of the houseplant is used in the treatment of nervous disorders, epilepsy and restless dreams. The leaves are edible and can be used as an addition to salads or stews. They are not particularly tasty, but as they are rich in water, they can be put in a juicer together with other fruits or vegetables and become a refreshing drink. It is used in folk herbal medicine and as a medicine. The aim of this study was to determine the moisture content, total extracted substances, extract density, vitamin C, organic acids and proteins in house extracts.


2021 ◽  
Vol 50 (9) ◽  
pp. 2675-2685
Author(s):  
Nur Diyana A. ◽  
Koh S.P. ◽  
Aziz N. ◽  
Hamid N.S.A. ◽  
Abdullah R. ◽  
...  

Mango leaves are known to possess many health benefits but the industry only focused on mango fruit production, resulting in abundant leaves being underutilized. In this study, we managed to transform mango leaves into a new fermented drink, which has a pleasant taste through the bio-fermentation process. Different maturity levels of mango leaves were selected; premature leaves (light brown, LBML), intermediate mature leaves (light green, LGML) and mature leaves (green, ML), which were subjected to a fermentation process using bacteria and yeast. Tannin content, organic acids profile and various enzymes functionality activities (e.g. inhibition of tyrosinase, elastase and acetylcholinesterase) studies were determined on fermented mango leaves drink. The reduction of tannins content in all fermented mango leaves resulted in a less astringent taste as a consequence of the microbial action to break down tannins. Acetic, oxalic, kojic and quinic acid are some of the organic acids detected in fermented mango leaves that contributed to its slightly acidic taste. In comparison to non-fermented mango leaves, all fermented samples, particularly LBML drink showed a significant improvement (P<0.05) in tyrosinase inhibition (87.96%). Fermented mango leaves also exhibited good inhibition activity towards elastase (>80%) and acetylcholinesterase (>90%). Further histopathology examination on various rat’s organs (kidney, liver, spleen, and stomach) showed no sign of inflammation symptoms. Through limit toxicological evaluation, the safety consumption rate (IC50 value) for fermented mango leaves was 1000 mL/50 kg of human bodyweight. The improvement functionality activities of fermented mango leaves with a higher inhibition rate against tyrosinase, elastase, and acetylcholinesterase indicate its great potential as a food remedy for anti-ageing treatment.


1993 ◽  
Vol 60 (4) ◽  
pp. 581-591 ◽  
Author(s):  
Nicla Zezza ◽  
Gabriella Pasini ◽  
Angiolella Lombardi ◽  
Annick Mercenier ◽  
Paolo Spettoli ◽  
...  

SummaryWe report the isolation and immobilization of a nisinogenic strain (NZ1) ofLactococcus lactissubsp.lactis, active on gas-forming lactate-fermenting clostridia responsible for late blowing of Asiago and Montasio cheeses. The bacteriocin (nisin) produced by strain NZ1 is pronase-sensitive and is released in culture media during the growth phase. Using the sensitive indicator strainLactobacillus delbrueckiisubsp.bulgaricusNCDO 1489, a rapid microtitre plate based assay was developed for quantitative determination of the bacteriocin produced by NZ1 cells, either free or immobilized in gel beads. Scanning electron microscopy of cells immobilized in calcium alginate coated beads and viable counts of the surrounding medium showed that no cell leakage occurred during a 24 h assay. The bacteriocin released from immobilized cells reached, after 5 and 24 h, concentrations comparable to that of the free cell system after 3–4 h incubation in culture media.


1983 ◽  
Vol 92 (1) ◽  
pp. 91-96 ◽  
Author(s):  
Yukiko Iino ◽  
Tomonori Takasaka ◽  
Etsuro Hoshino ◽  
Yutaka Kaneko ◽  
Sachiko Tomioka ◽  
...  

Organic acids in the contents of the cholesteatoma sac from 28 cases were studied by gas chromatographic technique. Five volatile fatty acids (acetate, propionate, isobutyrate, butyrate and isovalerate) and lactate were detected in large amounts, which may lower the pH of the cholesteatoma content. These acids were considered to be derived from products of anaerobic microorganisms. Therefore, the contents from 12 cases were cultured anaerobically in a glove box. Obligate microorganisms were identified in 92% of the cases and Peptococcus, Bacteroides, and Clostridium species were frequently isolated. In vitro, such obligate anaerobes produced various organic acids from the cholesteatoma content. Facultatives such as Staphylococcus aureus and Proteus mirabilis produced acetate in the content under aerobic and anaerobic conditions, whereas no organic acid was produced by Pseudomonas aeruginosa. Organic acids in the cholesteatoma content could be fermentative products made by the microorganisms, anaerobes and facultatives, which use the content as a substrate for acid production.


Polymers ◽  
2020 ◽  
Vol 12 (11) ◽  
pp. 2460
Author(s):  
Yingqi Mi ◽  
Wenqiang Tan ◽  
Jingjing Zhang ◽  
Zhanyong Guo

A novel and green method for the preparation of chitosan derivatives bearing organic acids was reported in this paper. In order to improve the antioxidant activity of chitosan, eight different hydroxypropyltrimethyl ammonium chitosan derivatives were successfully designed and synthesized via introducing of organic acids onto chitosan by mild and non-toxic ion exchange. The data of Fourier Transform Infrared (FTIR), 13C Nuclear Magnetic Resonance (NMR), 1H NMR, and elemental analysis for chitosan derivatives indicated the successful conjugation of organic acid salt with hydroxypropyltrimethyl ammonium chloride chitosan (HACC). Meanwhile, the antioxidant activity of the chitosan derivatives was evaluated in vitro. The results indicated that the chitosan derivatives possessed dramatic enhancements in DPPH-radical scavenging activity, superoxide-radical scavenging activity, hydroxyl radical scavenging ability, and reducing power. Furthermore, the cytotoxicity of the synthesized compounds was investigated in vitro on L929 cells and showed low cytotoxicity. Thus, the enhanced antioxidant property of all novel chitosan products might be a great advantage, while applied in a wide range of applications in the form of antioxidant in biomedical, food, and cosmetic industry.


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