Multifunctional Gold Nanozyme-Engineered Amphotericin B for Enhanced Antifungal Infection Therapy.

Chronic wounds of significant severity and acute injuries are highly vulnerable to fungal infections, drastically impeding the expected wound healing trajectory. The clinical use of antifungal therapeutic drug is hampered by poor solubility, high toxicity and adverse reactions, thereby necessitating the urgent development of novel antifungal therapy strategy. Herein, this study proposes a new strategy to enhance the bioactivity of small-molecule antifungal drugs based on multifunctional metal nanozyme engineering, using amphotericin B (AmB) as an example. AmB-decorated gold nanoparticles (AmB@AuNPs) are synthesized by a facile one-pot reaction strategy, and the AmB@AuNPs exhibit superior peroxidase (POD)-like enzyme activity, with maximal reaction rates (Vmax ) 3.4 times higher than that of AuNPs for the catalytic reaction of H2 O2 . Importantly, the enzyme-like activity of AuNPs significantly enhanced the antifungal properties of AmB, and the minimum inhibitory concentrations of AmB@AuNPs against Candida albicans (C. albicans) and Saccharomyces cerevisiae (S. cerevisiae) W303 are reduced by 1.6-fold and 50-fold, respectively, as compared with AmB alone. Concurrent in vivo studies conducted on fungal-infected wounds in mice underscored the fundamentally superior antifungal ability and biosafety of AmB@AuNPs. The proposed strategy of engineering antifungal drugs with nanozymes has great potential for enhanced therapy of fungal infections and related diseases.

Overview of mechanisms of Fe-based catalysts for the selective catalytic reduction of NOx with NH3 at low temperature.

With the increasingly stringent control of NOx emissions, NH3-SCR, one of the most effective de-NOx technologies for removing NOx, has been widely employed to eliminate NOx from automobile exhaust and industrial production. Researchers have favored iron-based catalysts for their low cost, high activity, and excellent de-NOx performance. This paper takes a new perspective to review the research progress of iron-based catalysts. The influence of the chemical form of single iron-based catalysts on their performance was investigated. In the section on composite iron-based catalysts, detailed reviews were conducted on the effects of synergistic interactions between iron and other elements on catalytic performance. Regarding loaded iron-based catalysts, the catalytic performance of iron-based catalysts on different carriers was systematically examined. In the section on iron-based catalysts with novel structures, the effects of the morphology and crystallinity of nanomaterials on catalytic performance were analyzed. Additionally, the reaction mechanism and poisoning mechanism of iron-based catalysts were elucidated. In conclusion, the paper delved into the prospects and future directions of iron-based catalysts, aiming to provide ideas for the development of iron-based catalysts with better application prospects. The comprehensive review underscores the significance of iron-based catalysts in the realm of de-NOx technologies, shedding light on their diverse forms and applications. The hope is that this paper will serve as a valuable resource, guiding future endeavors in the development of advanced iron-based catalysts.

Therapeutic effect of iturin A on Candida albicans oral infection and its pathogenic factors.

Candida albicans is responsible for conditions ranging from superficial infections such as oral or vaginal candidiasis to potentially fatal systemic infections. It produces pathogenic factors contributing to its virulence. Iturin A, a lipopeptide derived from Bacillus sp., exhibits a significant inhibitory effect against C. albicans. However, its exact mechanism in mitigating the pathogenic factors of C. albicans remains to be elucidated. This study aimed to explore the influence of iturin A on several pathogenic attributes of C. albicans, including hypha formation, cell membrane permeability, cell adhesion, biofilm formation, and therapeutic efficacy in an oral C. albicans infection model in mice. The minimal inhibitory concentration of iturin A against C. albicans was determined to be 25 µg/mL in both YEPD and RPMI-1640 media. Iturin A effectively inhibited C. albicans hyphal formation, decreased cell viability within biofilms, enhanced cell membrane permeability, and disrupted cell adhesion in vitro. Nonetheless, iturin A did not significantly affect the phospholipase activity or hydrophobicity of C. albicans. A comparative study with nystatin demonstrated the superior therapeutic efficacy of iturin A in a mouse model of oral C. albicans infection, significantly decreasing C. albicans count and inhibiting both fungal hypha formation and tongue surface adhesion. High-dose iturin A treatment (25 µg/mL) in mice had no significant effects on blood indices, tongue condition, or body weight, indicating the potential for iturin A in managing oral infections. This study confirmed the therapeutic potential of iturin A and provided valuable insights for developing effective antifungal therapies targeting C. albicans pathogenic factors.

Human dendritic cell subsets in the glioblastoma-associated microenvironment.

Glioblastoma (GBM) is the most aggressive type of glioma (Grade IV). The presence of cytotoxic T lymphocyte (CTLs) has been associated with improved outcomes in patients with GBM, and it is believed that the activation of CTLs by dendritic cells may play a critical role in controlling the growth of GBM. DCs are professional antigen-presenting cells (APC) that orchestrate innate and adaptive anti-GBM immunity. DCs can subsequently differentiate into plasmacytoid DCs (pDC), conventional DC1 (cDC1), conventional (cDC2), and monocyte-derived DCs (moDC) depending on environmental exposure. The different subsets of DCs exhibit varying functional capabilities in antigen presentation and T cell activation in producing an antitumor response. In this review, we focus on recent studies describing the phenotypic and functional characteristics of DC subsets in humans and their respective antitumor immunity and immunotolerance roles in the GBM-associated microenvironment. The critical components of crosstalk between DC subsets that contribute significantly to GBM-specific immune responses are also highlighted in this review with reference to the latest literature. Since DCs could be prime targets for therapeutic intervention, it is worth summarizing the relevance of DC subsets with respect to GBM-associated immunologic tolerance and their therapeutic potential.

A review of regeneration mechanism and methods for reducing soot emissions from diesel particulate filter in diesel engine.

With the global emphasis on environmental protection and the proposal of the climate goal of "carbon neutrality," countries around the world are calling for reductions in carbon dioxide, nitrogen oxide, and particulate matter pollution. These pollutants have severe impacts on human lives and should be effectively controlled. Engine exhaust is the most serious pollution source, and diesel engine is an important contributor to particulate matter. Diesel particulate filter (DPF) technology has proven to be an effective technology for soot control at the present and in the future. Firstly, the exacerbating effect of particulate matter on human infectious disease viruses is discussed. Then, the latest developments in the influence of key factors on DPF performance are reviewed at different observation scales (wall, channel, and entire filter). In addition, current soot catalytic oxidant schemes are presented in the review, and the significance of catalyst activity and soot oxidation kinetic models are highlighted. Finally, the areas that need further research are determined, which has important guiding significance for future research. Current catalytic technologies are focused on stable materials with high mobility of oxidizing substances and low cost. The challenge of DPF optimization design is to accurately calculate the balance between soot and ash load, DPF regeneration control strategy, and exhaust heat management strategy.

Modifications of Ganoderma lucidum spores into digestive-tissue highly adherent porous carriers with selective affinity to hydrophilic or hydrophobic drugs.

Ganoderma lucidum spores (GLSs) have been suggested to provide optimal structures for transporting orally bioavailable drugs. However, the double-layer wall and cavities of GLSs are naturally closed. This study aimed to modify GLSs into porous carriers by opening the layers and internal cavity with iturin A (IA) followed by potassium hydroxide (KOH) or hydrochloric acid (HCl). The (IA + KOH)- and (IA + HCl)-treated GLS carriers exhibited a high loading rate of 301.50 ± 2.33 and 268.18 ± 7.72 mg/g for the hydrophilic methylene blue (MB) and hydrophobic rifampicin (RF), respectively. The mechanisms underlying the modification involved the enhancement of the specific surface area with IA and the exposure of hydrophilic groups or hydrophobic groups of the GLSs with KOH or HCl. The sustained 48-h molecule-release profiles of the MB- and RF-loaded GLS carriers were best fitted using a first-order kinetics model in simulated gastric (or intestinal) fluid compared with other models. In mice, the designed GLS carriers had high adhesion capacities onto the mucosa of the digestive tract and long retention times (120 h), and even promoted the secretion of mucus and expression of several key intestinal barrier proteins. This study provided a new method to modify GLSs into oral carriers with selective drug affinity, high loading capacity, sustained drug release, and high adhesion to the digestive tract.

Hyperglycosylated N-Linked Site 339 of gp120 Appears to Be Unique and May Contribute to CRF01_AE Transmission Among Men Who Have Sex with Men in China and Thailand.

Human immunodeficiency virus (HIV)-1 CRF01_AE is one of the most important genotypes in China, especially in the population of men who have sex with men (MSM). It has become the most prevalent strain among them. Describing the variant characterization of CRF01_AE will help to reveal the reason behind its predominance in MSM. In this study, the complete DNA sequences (CDSs) for gp120 from the envelope protein (env) gene of CRF01_AE in China and Thailand were retrieved from the Los Alamos HIV database. The CDSs for gp120 were divided into three subgroups according to the risk factors for HIV-1 transmission in a variety of populations, such as intravenous drug users (IDU), heterosexual contacts (HC), and MSM. The N-linked CDS glycosylation sites for gp120 in CRF01_AE were analyzed. The results showed a unique hyperglycosylation site N-339 (refer to Hxb2) in the gp120 of CRF01_AE in MSM compared with the IDU and HC groups from China. The result was the same in the MSM group from Thailand, which suggests that the hyperglycosylation site N-339 may explain the widespread CRF01_AE genotype in MSM.

Energy metabolic mechanisms for high altitude sickness: Downregulation of glycolysis and upregulation of the lactic acid/amino acid-pyruvate-TCA pathways and fatty acid oxidation.

Hypobaric hypoxia is often associated with the plateau environment and can lead to altitude sickness or death. The underlying cause is a lack of oxygen, which limits energy metabolism and leads to a compensatory stress response. Although glycolysis is commonly accepted as the primary energy source during clinical hypoxia, our preliminary experiments suggest that hypobaric hypoxia may depress glycolysis. To provide a more comprehensive understanding of energy metabolism under short-term hypobaric hypoxia, we exposed mice to a simulated altitude of 5000 m for 6 or 12 h. After the exposure, we collected blood and liver tissues to quantify the substrates, enzymes, and metabolites involved in glycolysis, lactic acid metabolism, the tricarboxylic acid cycle (TCA), and fatty acid ß-oxidation. We also performed transcriptome and enzymatic activity analyses of the liver. Our results show that 6 h of hypoxic exposure significantly increased blood glucose, decreased lactic acid and triglyceride concentrations, and altered liver enzyme activities of mice exposed to hypoxia. The key enzymes in the glycolytic, TCA, and fatty acid ß-oxidation pathways were primarily affected. Specifically, the activities of key glycolytic enzymes, such as glucokinase, decreased significantly, while the activities of enzymes in the TCA cycle, such as isocitrate dehydrogenase, increased significantly. Lactate dehydrogenase, pyruvate carboxylase, and alanine aminotransferase were upregulated. These changes were partially restored when the exposure time was extended to 12 h, except for further downregulation of phosphofructokinase and glucokinase. This study demonstrates that acute high altitude hypoxia upregulated the lactic acid/amino acid-pyruvate-TCA pathways and fatty acid oxidation, but downregulated glycolysis in the liver of mice. The results obtained in this study provide a theoretical framework for understanding the mechanisms underlying the pathogenesis of high-altitude sickness in humans. Additionally, these findings have potential implications for the development of prevention and treatment strategies for altitude sickness.

High homocysteine is associated with idiopathic normal pressure hydrocephalus in deep perforating arteriopathy: a cross-sectional study.

BACKGROUND AND OBJECTIVE: The pathogenesis and pathophysiology of idiopathic normal pressure hydrocephalus (iNPH) remain unclear. Homocysteine may reduce the compliance of intracranial arteries and damage the endothelial function of the blood-brain barrier (BBB), which may be the underlying mechanism of iNPH. The overlap cases between deep perforating arteriopathy (DPA) and iNPH were not rare for the shared risk factors. We aimed to investigate the relationship between serum homocysteine and iNPH in DPA. METHODS: A total of 41 DPA patients with iNPH and 49 DPA patients without iNPH were included. Demographic characteristics, vascular risk factors, laboratory results, and neuroimaging data were collected. Multivariable logistic regression analysis was performed to investigate the relationship between serum homocysteine and iNPH in DPA patients. RESULTS: Patients with iNPH had significantly higher homocysteine levels than those without iNPH (median, 16.34 mmol/L versus 14.28 mmol/L; P = 0.002). There was no significant difference in CSVD burden scores between patients with iNPH and patients without iNPH. Univariate logistic regression analysis demonstrated that patients with homocysteine levels in the Tertile3 were more likely to have iNPH than those in the Tertile1 (OR, 4.929; 95% CI, 1.612-15.071; P = 0.005). The association remained significant after multivariable adjustment for potential confounders, including age, male, hypertension, diabetes mellitus, atherosclerotic cardiovascular disease (ASCVD) or hypercholesterolemia, and eGFR level. CONCLUSION: Our study indicated that high serum homocysteine levels were independently associated with iNPH in DPA. However, further research is needed to determine the predictive value of homocysteine and to confirm the underlying mechanism between homocysteine and iNPH.

Preventive and therapeutic effects of an exopolysaccharide produced by Lacticaseibacillus rhamnosus on alcoholic gastric ulcers.

Crude exopolysaccharides produced by Lacticaseibacillus rhamnosus SHA113 were previously found to exhibit anti-alcoholic gastric ulcer activity in mice, but their major active fraction, structural characteristics, and underlying mechanisms remain unknown. Here, LRSE1 was identified as the active exopolysaccharide fraction produced by L. rhamnosus SHA113 responsible for the above effects. Purified LRSE1 had a molecular weight of 4.9 × 104 Da and was comprised of L-fucose, D-mannose, D-glucuronic acid, d-glucose, D-galactose, and L-arabinose in the molar ratio of 2.4:6.5:1.2:1.00:0.3:0.6, respectively. The oral administration of LRSE1 resulted in a significant protective and therapeutic effect on alcoholic gastric ulcers in mice. These effects were identified to involve a reduction in reactive oxygen species, apoptosis, and the inflammatory response, increases in antioxidant enzyme activities, and increases in the phylum Firmicutes and decreases in the genera Enterococcus, Enterobacter, and Bacteroides in the gastric mucosa of mice. In vitro experiments showed that the administration of LRSE1 both inhibited apoptosis in GEC-1 cells via the TRPV1-P65-Bcl-2 pathway and inhibited the inflammatory response in RAW264.7 cells via the TRPV1-PI3K pathway. For the first time, we have identified the active exopolysaccharide fraction produced by Lacticaseibacillus that protects against alcoholic gastric ulcers and determined that its effect involves TRPV1-mediated pathways.

A novel probability integral method segmental modified model for subsidence prediction applicable to thick loose layer mining areas.

In response to the problem that the actual extent of coal mining impacts on the surface in thick loose layer mines significantly exceeds the theoretical predictions, based on the literature study, the form of influence of thick loose layer on the predicted parameters of the probability integral method is summarized and analyzed; taking into account the influence of the subsidence coefficient, the sine modification formula of the major influence radius and the logistic modification formula of the subsidence coefficient are established, respectively, and based on the characteristics of the major influence radius, a new subsidence basin demarcation point is proposed and a novel probability integral method segmental parameter modified prediction model is constructed. The simulated experiment and real data experiment results prove that the constructed probability integral method segmented parameter modified model can both reduce the convergence of surface subsidence basin edge better and take into account the predicted accuracy inside the subsidence basin. The research achievements provide scientific data support for disaster warning, pollution management, ecological restoration, and coordination between coal mining and surface city construction in thick loose layer mining areas.

Microgravity and immune cells.

The microgravity environment experienced during spaceflight severely impaired immune system, making astronauts vulnerable to various diseases that seriously threaten the health of astronauts. Immune cells are exceptionally sensitive to changes in gravity and the microgravity environment can affect multiple aspects of immune cells through different mechanisms. Previous reports have mainly summarized the role of microgravity in the classification of innate and adaptive immune cells, lacking an overall grasp of the laws that microgravity effects on immune cells at different stages of their entire developmental process, such as differentiation, activation, metabolism, as well as function, which are discussed and concluded in this review. The possible molecular mechanisms are also analysed to provide a clear understanding of the specific role of microgravity in the whole development process of immune cells. Furthermore, the existing methods by which to reverse the damage of immune cells caused by microgravity, such as the use of polysaccharides, flavonoids, other natural immune cell activators etc. to target cell proliferation, apoptosis and impaired function are summarized. This review will provide not only new directions and ideas for the study of immune cell function in the microgravity environment, but also an important theoretical basis for the development of immunosuppression prevention and treatment drugs for spaceflight.

Early clinical efficacy of pegylated interferon treatment in patients with different phases of chronic HBV infection: A real-world analysis.

Although there are therapeutic advantages for hepatitis B virus (HBV) withpegylated interferon alpha (peg-IFNα) treatment compared with nucleos(t)ide analog (NAs) therapy, the effect difference in infected population at different phases has not been well established. We studied the clinical efficacy of peg-IFNα in two populations with HBV infection, including inactive HBsAg carrier (IHC) and chronic hepatitis B (CHB). A total of 328 HBV-infected patients were included in this real-world analysis. Patients were divided into two groups according to the infected stages. Peg-IFNα monotherapy or combination therapy with NAs were used in IHCs, and peg-IFNα added-on NAs therapy was applied to patients with CHB. The primary efficacy endpoint was HBsAg loss at Week 24. Results: The Kaplan-Meier cumulative rates of HBsAg loss were 39.50% (n = 47/119) in IHC group and 28.71% (n = 60/209) in CHB group at Week 24 (p < .05). After Propensity Score Matching (PSM), the HBsAg loss rates were 36.84% (n = 35/95) and 32.63% (n = 31/95), respectively (p > .05). Patients with baseline HBsAg level < 100 IU/ml achieved higher rates of HBsAg clearance in IHC and CHB group (before PSM: 47.44% vs. 42.86%, after PSM: 49.12% vs. 45.83%, all p values > .05). Baseline HBsAg level and its level decline from baseline to Week 12 can be as the predictors for HBsAg loss at Week 24 in both groups. Hence, the efficacy of HBsAg clearance was broadly similar between IHCs and NA-treated CHB patients during the early peg-IFNα therapy. A significant downward trend of HBsAg level was observed in both groups during peg-IFNα therapy.

Potential role of selenium in alleviating obesity-related iron dyshomeostasis.

Obesity is a serious health problem in modern life and increases the risk of many comorbidities including iron dyshomeostasis. In contrast to malnourished anemia, obesity-related iron dyshomeostasis is mainly caused by excessive fat accumulation, inflammation, and disordered gut microbiota. In obesity, iron dyshomeostasis also induces disorders associated with gut microbiota, neurodegenerative injury, oxidative damage, and fat accumulation in the liver. Selenium deficiency is often accompanied by obesity or iron deficiency, and selenium supplementation has been shown to alleviate obesity and overcome iron deficiency. Selenium inhibits fat accumulation and exhibits anti-inflammatory activity. It regulates gut microbiota, prevents neurodegenerative injury, alleviates oxidative damage to the body, and ameliorates hepatic fat accumulation. These effects theoretically meet the requirements for the inhibition of factors underlying obesity-related iron dyshomeostasis. Selenium supplementation may have a potential role in the alleviation of obesity-related iron dyshomeostasis. This review verifies this hypothesis in theory. All the currently reported causes and results of obesity-related iron dyshomeostasis are reviewed comprehensively, together with the effects of selenium. The challenges and strategies of selenium supplementation are also discussed. The findings demonstrate the possibility of selenium-containing drugs or functional foods in alleviating obesity-related iron dyshomeostasis.

Safety of AS04-HPV-16/18 vaccine in Chinese women aged 26 years and older and long-term protective effect in women vaccinated at age 18-25 years: A 10-year follow-up study.

INTRODUCTION: The pivotal efficacy study assessed efficacy and safety of GSK's AS04-HPV-16/18 vaccine in Chinese women aged 18-25 years up to 6 years. The present extension study, performed 4 years later, offered AS04-HPV-16/18 vaccination to placebo recipients. Vaccine safety and its long-term protective effect were assessed at Year 10. METHODS: All 6051 women who received AS04-HPV-16/18 or the placebo during the initial study (NCT00779766) were invited to phase III/IV, open-label, partially controlled extension Year 10 study (NCT03629886). Placebo recipients were offered three-dose AS04-HPV-16/18 vaccination and followed up over 12 months to assess the safety. Cervical samples from all women were examined. Vaccine efficacy (VE) against incident infections and cytological lesions associated with HPV-16/18 and other oncogenic types was assessed as exploratory objective. RESULTS: Among 3537 women (out of 6051) enrolled in the extension study, 1791 women (mean age 32.7 years; standard deviation 1.8 years) received AS04-HPV-16/18 and reported no serious adverse events, potential immune-mediated diseases, or adverse pregnancy outcomes related to vaccination. Among 6051 women, VE against incident HPV-16, -18, and -16/18 infections up to Year 10 was 82.8% (95% confidence interval: 72.5-89.7), 79.8% (64.5-89.2), and 80.8% (72.4-87.0), respectively. VE against HPV-16/18 ASC-US+, CIN1+, and CIN2+ was 92.7% (82.2-97.7), 94.8% (67.4-99.9), and 90.5% (34.6-99.8), respectively. CONCLUSION: AS04-HPV-16/18 vaccine showed an acceptable safety profile in Chinese women vaccinated at age 26 years or above, and a long-term protection similar to other efficacy trials worldwide.

Simulated Microgravity Accelerates Alloy Corrosion by Aspergillus sp. via the Enhanced Production of Organic Acids.

Metal corrosion caused by Aspergillus sp. was shown to be significantly enhanced on a space station, but its mechanism is still unknown. To simulate this on earth, the corrosion capability of A. carbonarius on five metal sheets was investigated under simulated microgravity. Also, the effect of metal ions on growth and organic acid production was determined. Results showed that A. carbonarius could corrode all five types of metal, including Ti alloy, aluminum alloy, iron, and aluminum and copper sheet, and the corrosion was intensified under simulated microgravity. Energy dispersive X-ray spectrometry (EDS) analysis showed that metal ions enriched on A. carbonarius spores, especially iron, aluminum ions, and copper ions, indicating that A. carbonarius can use these metal ions. In particular, the content of oxalic acid was significantly increased after A. carbonarius cocultured with five metal materials under simulated microgravity. Al3+, Fe3+, and Cu2+ at the concentration of 0.3 mg/mL and Mg2+ at 0.8 mg/mL significantly promoted the growth and oxalic acid and citric acid production of A. carbonarius and A. niger under normal gravity and simulated microgravity. Comparing the impact of metal ions and metal sheets on the production of organic acids, it can be inferred that oxalic acid may dominate in the corrosion process of A. carbonarius. In summary, molds promoted metal corrosion by producing organic acids, and the released metal ions will further promote the growth of mold and the accumulation of organic acids. This may be an important reason for the intensification of mold corrosion under microgravity. IMPORTANCE The space station and other long-term manned spacecrafts will experience the risk of microbial corrosion, especially mold, which will be harmful to the platform system and astronauts. Aspergillus sp. has been widely reported to produce organic acids that corrode and destroy materials, and the ability of these crafts to fly through space can be significantly affected. Research on the mechanism that causes enhanced corrosion ability of fungi in space stations is important to control their growth. Our research focuses on the interaction between mold and metals. In particular, it is found that metal ions promote mold growth and produce organic acids, thus accelerating mold corrosion of metals. Our results provide a new perspective for the control of fungal corrosion under simulated microgravity.

The clinical effect of WeChat-based MUST education model on patients with chronic heart failure.

OBJECTIVE: To explore the effect of WeChat-based MUST nursing intervention on self-care ability and quality of life in patients with chronic heart failure. METHOD: Convenient sampling was used to select CHF patients who received treatment in XX Hospital from January 1, 2020, to December 30, 2020, as the study subjects and was divided into the experimental group (n = 60) and the control group (n = 60) according to the random number table. The experimental group used the WeChat-based MUST nursing intervention, and the control group used the routine education and follow-up model. Cardiac function parameters, self-care ability, and other indicators were compared between the two groups before and after nursing. The clinical effect of two groups was evaluated. RESULTS: After the nursing intervention, LVEF levels were increased to different extents and NT-proBNP was decreased to different extents in both groups. LVEF level in the experimental group was higher than that in the control group, and the NT-proBNP level in the experimental group was lower than that in the control group. After the nursing intervention, the self-care ability and quality of life of the two groups were increased to varying degrees. Self-care ability was higher in the experimental group than in the control group, and quality of life was higher in the experimental group than in the control group. CONCLUSION: The WeChat-based MUST nursing intervention model in patients with chronic heart failure, compared with the conventional cardiology nursing model, can effectively improve the self-care ability of patients, improve the knowledge level and quality of life of patients with heart failure, and reduce the readmission rate.

Development of a microecologic product from Lactobacillus rhamnosus based on silica.

BACKGROUND: Probiotics are primarily made into microecologic products for use in the food and feed industries. The freeze-drying technique is widely used in their preparation to maintain their high level of bioactivity. This causes high costs in terms of the energy and time needed. In this study, we developed a method to produce a highly active microecologic product from Lactobacillus rhamnosus using heating and silica. RESULTS: A microecologic product was made successfully from L. rhamnosus using the whole bacterial culture broth, without waste, and using food-grade silica (4.5 mL g-1 ) to absorb water before drying at 37 °C for 8 h. The activity of L. rhamnosus cells was increased significantly by adding water extracts of green tea to the culture medium. The viable amount of L. rhamnosus in the obtained microecologic product was 9.80 × 1010 cfu g-1 with a survival rate of 224.67% in simulated gastric juice for 3 h and 68.2% in simulated intestinal juice for 3 h. The microecologic product treated an intestinal infection by multi-drug-resistant Staphylococcus aureus in mice very efficiently. CONCLUSION: The study developed an economic, eco-friendly, and efficient method for preparing highly active microecologic agents using heating and without waste. © 2022 Society of Chemical Industry.