Microbial transglutaminase (MTG) is an enzyme widely used in the food industry because it creates cross-links between proteins, enhancing the texture and stability of food products. Its unique properties make it a valuable tool for modifying the functional characteristics of proteins, significantly impacting the quality and innovation of food products. In this study, response surface methodology was employed to optimize the fermentation conditions for microbial transglutaminase production by the strain Streptoverticillium cinnamoneum KKP 1658. The effects of nitrogen dose, cultivation time, and initial pH on the activity of the produced transglutaminase were investigated. The significance of the examined factors was determined as follows: cultivation time > nitrogen dose > pH. The interaction between nitrogen dose and cultivation time was found to be crucial, having the second most significant impact on transglutaminase activity. Optimal conditions were identified as 48 h of cultivation with a 2% nitrogen source dose and an initial medium pH of approximately 6.0. Under these conditions, transglutaminase activity ranged from 4.5 to 5.5 U/mL. The results of this study demonstrated that response surface methodology is a promising approach for optimizing microbial transglutaminase production. Future applications of transglutaminase include the development of modern food products with improved texture and nutritional value, as well as its potential use in regenerative medicine for creating biomaterials and tissue scaffolds. This topic is particularly important and timely as it addresses the growing demand for innovative and sustainable solutions in the food and biomedical industries, contributing to an improved quality of life.
In screening biocontrol strains with broad-spectrum and high-efficiency herbicidal activities, a strain with strong pathogenicity, HY-021, was isolated from the leaves of Rumex acetosa, which was identified as Botrytis fabiopsis based on morphology and molecular biology. The herbicidal activities of the fermentation filtrate of strain HY-021 against nine weeds, including Chenopodium album L., Elsholtzia densa Benth., Malva verticillata L. var. Crispa, Polygonum lapathifolium L., Amaranthus retroflexus L., Avena fatua L., Thlaspi arvense L., Polygonum aviculare L., and Galium spurium L., were determined in vitro and in vivo. The results showed that the pathogenicity of strain HY-021 to the different weeds in vitro was as follows: E. densa > A. retroflexus > P. aviculare > P. lapathifolium > M. verticillata > T. arvense > G. spurium > A. fatua > C. album. Seven days after inoculation with the HY-021 strain, the incidences in nine weeds were in the range of 32.9-87.23%, and the disease index values of the nine weeds were 41.73-94.57%. The pathogenic effects from high to low were A. retroflexus > E. densa > A. fatua > G. spurium > C. album > M. verticillata > T. arvense > P. aviculare > P. lapathifolium. The crop safety test showed that the biocontrol strain HY-021 was safe to V. faba, P. sativum, H. vulgare, and T. aestivum, but had a slight effect on B. napus. Scanning electron microscopy showed that the mycelium of strain HY-021 invaded the tissue through the stomata of C. album leaves, parasitized and reproduced in the tissue, and gradually destroyed the tissue. The results of this study provide a basis for the development and utilization of new and efficient microbial source herbicides.
- MeSH
- Pest Control, Biological * methods MeSH
- Biological Control Agents * MeSH
- Botrytis * isolation & purification physiology genetics pathogenicity MeSH
- Herbicides metabolism pharmacology MeSH
- Weed Control * methods MeSH
- Plant Leaves microbiology MeSH
- Plant Diseases * microbiology prevention & control MeSH
- Plant Weeds * microbiology MeSH
- Publication type
- Journal Article MeSH
- Geographicals
- China MeSH
Yeasts are unicellular fungi that occur in a wide range of ecological niches, where they perform numerous functions. Furthermore, these microorganisms are used in industrial processes, food production, and bioremediation. Understanding the physiological and adaptive characteristics of yeasts is of great importance from ecological, biotechnological, and industrial perspectives. In this context, we evaluated the abilities to assimilate and ferment different carbon sources, to produce extracellular hydrolytic enzymes, and to tolerate salt stress, heavy metal stress, and UV-C radiation of two isolates of Eremothecium coryli, isolated from Momordica indica fruits. The two isolates were molecularly identified based on sequencing of the 18S-ITS1-5.8S-ITS2 region. Our isolates were able to assimilate nine carbon sources (dextrose, galactose, mannose, cellobiose, lactose, maltose, sucrose, melezitose, and pectin) and ferment three (glucose, maltose, and sucrose). The highest values of cellular dry weight were observed in the sugars maltose, sucrose, and melezitose. We observed the presence of hyphae and pseudohyphae in all assimilated carbon sources. The two isolates were also capable of producing amylase, catalase, pectinase, and proteases, with the highest values of enzymatic activity found in amylase. Furthermore, the two isolates were able to grow in media supplemented with copper, iron, manganese, nickel, and zinc and to tolerate saline stress in media supplemented with 5% NaCl. However, we observed a decrease in CFU at higher concentrations of these metals and NaCl. We also observed morphological changes in the presence of metals, which include changes in cell shape and cellular dimorphisms. The isolates were sensitive to UV-C radiation in the shortest exposure time (1 min). Our findings reinforce the importance of endophytic yeasts for biotechnological and industrial applications and also help to understand how these microorganisms respond to environmental variations caused by human activities.
- MeSH
- Endophytes * isolation & purification genetics metabolism physiology classification radiation effects MeSH
- Fermentation MeSH
- Phylogeny MeSH
- Stress, Physiological * MeSH
- Carbohydrate Metabolism * MeSH
- Fruit * microbiology MeSH
- Saccharomycetales * isolation & purification genetics physiology metabolism radiation effects classification MeSH
- Metals, Heavy toxicity MeSH
- Ultraviolet Rays MeSH
- Publication type
- Journal Article MeSH
Apple replant disease (ARD) is a significant factor restricting the healthy development of the apple industry. Biological control is an important and sustainable method for mitigating ARD. In this study, a strain of Paenibacillus polymyxa GRY-11 was isolated and screened from the rhizosphere soil of healthy apple trees in old apple orchards in Shandong Province, China, and the effects of strain GRY-11 on soil microbial community and ARD were studied. The result showed that P. polymyxa GRY-11 could effectively inhibit the growth of the main pathogenic fungi that caused ARD, and the inhibition rates of the strain against Fusarium moniliforme, Fusarium proliferatum, Fusarium solani, and Fusarium oxysporum were 80.00%, 71.60%, 75.00%, and 70.00%, respectively. In addition, the fermentation supernatant played an active role in suppressing the growth of pathogenic fungi. The results of the pot experiment showed that the bacterial fertilizer of the GRY-11 promoted the growth of Malus hupehensis seedlings, improved the activity of protective enzymes in plant roots, enhanced the soil enzyme content, and optimized the soil microbial environment. In general, the GRY-11 can be used as an effective microbial preparation to alleviate ARD. Our study offers novel perspectives for the prevention of ARD.
- MeSH
- Antibiosis MeSH
- Pest Control, Biological * MeSH
- Biological Control Agents * MeSH
- Fusarium growth & development MeSH
- Fungi growth & development MeSH
- Plant Roots microbiology MeSH
- Malus * microbiology growth & development MeSH
- Plant Diseases * microbiology prevention & control MeSH
- Paenibacillus polymyxa * isolation & purification physiology genetics classification MeSH
- Soil Microbiology MeSH
- Rhizosphere MeSH
- Publication type
- Journal Article MeSH
- Geographicals
- China MeSH
Feruloyl esterases (FAEs) are a crucial component of the hemicellulose-degrading enzyme family that facilitates the degradation of lignocellulose while releasing hydroxycinnamic acids such as ferulic acid with high added value. Currently, the low enzyme yield of FAEs is one of the primary factors limiting its application. Therefore, in this paper, we optimized the fermentation conditions for the expression of FAE BpFaeT132C-D143C with excellent thermal stability in Escherichia coli by experimental design. Firstly, we explored the effects of 11 factors such as medium type, isopropyl-β-D-thiogalactopyranoside (IPTG) concentration, and inoculum size on BpFaeT132C-D143C activity separately by the single factor design. Then, the significance of the effects of seven factors, such as post-induction temperature, shaker rotational speed, and inoculum size on BpFaeT132C-D143C activity, was analyzed by Plackett-Burman design. We identified the main factors affecting the fermentation conditions of E. coli expressing BpFaeT132C-D143C as post-induction temperature, pre-induction period, and post-induction period. Finally, we used the steepest ascent path design and response surface method to optimize the levels of these three factors further. Under the optimal conditions, the activity of BpFaeT132C-D143C was 3.58 U/ml, which was a significant 6.6-fold increase compared to the pre-optimization (0.47 U/ml), demonstrating the effectiveness of this optimization process. Moreover, BpFaeT132C-D143C activity was 1.52 U/ml in a 3-l fermenter under the abovementioned optimal conditions. It was determined that the expression of BpFaeT132C-D143C in E. coli was predominantly intracellular in the cytoplasm. This study lays the foundation for further research on BpFaeT132C-D143C in degrading agricultural waste transformation applications.
- MeSH
- Escherichia coli * genetics metabolism enzymology MeSH
- Fermentation * MeSH
- Isopropyl Thiogalactoside metabolism MeSH
- Carboxylic Ester Hydrolases * genetics metabolism chemistry biosynthesis MeSH
- Culture Media chemistry MeSH
- Coumaric Acids metabolism MeSH
- Lignin MeSH
- Recombinant Proteins genetics metabolism biosynthesis chemistry MeSH
- Enzyme Stability MeSH
- Temperature MeSH
- Publication type
- Journal Article MeSH
In this study, lactic acid bacteria (LAB) isolation from fermented foods and molecular identification using magnetic bead technology were performed. And then exopolysaccharide (EPS) production possibility was tested in agar medium, and the positive ones were selected for the next step. The bacteria that could produce higher carbohydrate level were grown in MRS medium fortified with whey and pumpkin waste. In our study, 19 different LAB species were identified from fermented products collected from different places in Hatay (Türkiye) province. In molecular identification, universal primer pairs, p806R/p8FPL, and PEU7/DG74 were used for PCR amplification. After that, PCR products purified using paramagnetic bead technology were sequenced by the Sanger sequencing method. The dominant species, 23.8% of the isolates, were identified as Lactiplantibacillus plantarum. As a technological property of LAB, exopolysaccharide production capability of forty-two LAB isolate was tested in agar medium, and after eleven isolates were selected as positive. Two LAB (Latilactobacillus curvatus SHA2-3B and Loigolactobacillus coryniformis SHA6-3B) had higher EPS production capability when they were grown in MRS broth fortified with pumpkin waste and whey. The highest EPS content (1750 mg/L glucose equivalent) was determined in Loigolactobacillus coryniformis SHA6-3B grown in MRS broth fortified with 10% pumpkin waste. Besides the produced EPS samples were validated with FTIR and SEM methods.
- MeSH
- Polysaccharides, Bacterial * biosynthesis metabolism MeSH
- Cucurbita microbiology MeSH
- Fermentation MeSH
- Fermented Foods * microbiology MeSH
- Phylogeny MeSH
- Culture Media chemistry MeSH
- Lactobacillales * isolation & purification classification genetics metabolism MeSH
- Waste Products * analysis MeSH
- Food Microbiology * MeSH
- RNA, Ribosomal, 16S genetics MeSH
- Whey MeSH
- Publication type
- Journal Article MeSH
Stenotrophomonas maltophilia, Achromobacter xylosoxidans, and Burkholderia cenocepacia are considered emerging pathogens classified as a public health problem due to extensive antimicrobial resistance. Therefore, the discovery of new therapeutic strategies has become crucial. This study aimed to evaluate the antimicrobial activity of gallic acid and methyl gallate against non-fermenting bacteria. The study included five clinical isolates of Stenotrophomonas maltophilia, Achromobacter xylosoxidans, and Burkholderia cenocepacia. The minimum inhibitory concentrations of gallic acid and methyl gallate were determined by the broth microdilution method. Growth curves, metabolic activity, and biofilm formation of each bacterial strain in the presence or absence of phenolic compounds were performed. Finally, the therapeutic efficacy of the compounds was evaluated using an in vivo model. Gallic acid and methyl gallate showed antibacterial activity against bacterial strains in a concentration range of 64 to 256 μg/mL, both compounds reduced bacterial growth and metabolic activity of the strains, even at subinhibitory concentrations. Only, methyl gallate exhibited activity to inhibit the formation of bacterial biofilms. Moreover, gallic acid and methyl gallate increased larval survival by up to 60% compared to 30% survival of untreated larvae in a bacterial infection model in Galleria mellonella. Our results highlight the potential of gallic acid and methyl gallate as therapeutic alternatives for infections by emerging non-fermentative bacteria.
Three types of solid waste are produced during beer fermentation: spent grain, hot trub, and residual yeast. While the first is used as livestock feed, the seconds has not yet found any real reapplication in the field of circular economy. The aim of this work is to study and characterize these two brewing wastes, i.e., hot trub and residual yeast, to evaluate their potential reuse in the agricultural field. Samples from top-fermented and bottom-fermented beers were chemically investigated. Initially, the safety was assessed via multi-detection analysis of 57 mycotoxins, and all samples were deemed safe. Subsequently, the chemical and elemental composition was examined via ICP-MS and microanalysis, along with phenolic compounds and antioxidant activity via HPLC and spectrophotometric determinations, to achieve a thorough characterization of these waste samples. The C/N ratio of residual yeast from top-fermented beer and hot trub of the bottom-fermented one were near the optimal one (10:1). This research marks an initial step towards repurposing brewery waste materials as fertilizers. The subsequent steps will involve the formulation and field trials.
- Publication type
- Journal Article MeSH
Allodiploid hybrid species, Aspergillus latus, belonging to section Nidulantes, is a hybrid of A. spinulosporus and an unknown species closely related to A. quadrilineatus and A. sublatus. This hybrid has often been misidentified as the species in section Nidulantes, such as A. nidulans, A. spinulosporus, A. sublatus, or other cryptic species. Aspergillus latus has not been reported in Japan as well as Asia so far. In this study, we screened 23 clinical strains identified as A. spinulosporus isolated in Japan from 2012 to 2023 and found seven A. latus strains. To characterize the A. latus strains, we conducted comprehensive phenotyping including morphological observation, whole genome sequences, and phylogenetic analysis based on calmodulin (CaM) gene. In addition, we conducted antifungal susceptibility testing for A. latus strains. As a result, the morphological characters of A. latus were more similar to those of A. spinulosporus compared to A. sublatus. However, the ascospore of A. latus differed from that of A. spinulosporus. Phylogenetic analysis revealed that different CaM alleles from the same isolate clustered separately with A. spinulosporus and A. sublatus, consistent with its hybrid origin. Furthermore, A. latus strains showed reduced susceptibility to caspofungin and amphotericin B compared to A. spinulosporus, while they were susceptible to azoles. Our results suggest that A. latus has been a causative pathogen of aspergillosis in Japan since 2013.
- MeSH
- Antifungal Agents pharmacology MeSH
- Aspergillus * genetics classification isolation & purification drug effects MeSH
- Aspergillosis * microbiology epidemiology MeSH
- Phylogeny MeSH
- Calmodulin genetics MeSH
- Humans MeSH
- Microbial Sensitivity Tests MeSH
- Whole Genome Sequencing MeSH
- Check Tag
- Humans MeSH
- Publication type
- Journal Article MeSH
- Geographicals
- Japan MeSH
Alergie na bílkoviny kravského mléka je nejčastější potravinovou alergií u malých dětí a s věkem u většiny z nich vyhasíná. Léčba zahrnuje eliminaci mléčné bílkoviny ze stravy, což může vést k zásadním nutričním deficitům a její znovuzavedení by nemělo být zbytečně odkládáno. Účinnou metodou pro postupné zavedení mléčné bílkoviny v domácím prostředí jsou potravinové žebříky. Technologické úpravy mléčných bílkovin, jako je tepelná úprava a fermentace, mohou snížit jejich alergenicitu a zřejmě také urychlit nástup tolerance. Původně byly zavedeny do praxe pro pacienty s mírnými až středně těžkými non IgE reakcemi, novější studie však dokládají jejich využití také u některých IgE mediovaných alergií. Účinnost a bezpečnost těchto žebříků jsou ověřeny výzkumem. Pro naše prostředí nebyl dosud žádný potravinový žebřík k dispozici. Český mléčný žebřík je první svého druhu, vychází z doporučených postupů iMAP (International Milk Allergy in Primary Care) a byl přeložen a adaptován na české podmínky. Nyní je pro odborníky k dispozici na webu České asociace nutričních terapeutů včetně doprovodných materiálů.
Allergy to cow‘s milk protein is the most common food allergy in young children, and it fades with age in most of them. Treatment involves eliminating milk protein from the diet, which can lead to major nutritional deficiencies, and reintroduction should not be delayed unnecessarily. Food ladders are an effective method for gradually introducing milk protein in the home environment. Technological treatments of milk proteins, such as heat treatment and fermentation, can reduce their allergenicity and probably also accelerate the onset of tolerance. They were originally introduced into practice for patients with mild to moderate non IgE reactions, but more recent studies have documented their use in some IgE mediated allergies as well. The efficacy and safety of these ladders have been validated by research. No food ladder has yet been available for our setting. The Czech milk ladder is the first of its kind, based on the recommended iMAP (International Milk Allergy in Primary Care) procedures and has been translated and adapted to Czech conditions. It is now available for professionals on the website of the Czech Association of Dietitians including accompanying materials.
