Bacterium Streptococcus Research Articles

Modulation of Performance, Plasma Constituents, Small Intestinal Morphology, and Cecum Microbiota in Growing Geese by Dietary Citric Acid Supplementation.

To investigate the efficiency and optimum inclusion level of CA in growing geese diets on performance, plasma constituents, and intestinal health, 240 healthy female geese at the age of 28d were randomly allotted six treatment diets incorporated with 0, 0.8, 1.6, 2.4, 3.2, and 4% CA. Each treatment group consisted of five replicates and eight birds per replicate. The findings demonstrated that 3.2% CA supplementation resulted in improved growth performance (ADG, ADFI, and FBW) (p = 0.001), and geese who received CA also showed lower body fat contents (p < 0.05) than the control group. Moreover, geese from the 2.4% and 3.2% CA group had the highest plasma glutathione peroxidase and insulin-like growth factor 1 levels compared to the other groups (p < 0.05). A microbial diversity analysis of the cecum conducted by 16S rDNA sequencing revealed that 3.2% CA supplementation showed a significantly higher abundance of beneficial bacteria (Muribaculaceae, CHKCI001, Erysipelotricha-ceae_UCG_003, and UCG_009) (p < 0.05) and a lower abundance of harmful bacteria (Atopobiaceae, Streptococcus, Acinetobacter, Pseudomonas, and Alistipes) (p < 0.10). Collectively, our results revealed that dietary supplementation with 3.2% CA had several benefits on the performance and physiological health of growing geese by promoting nutrients metabolism, improving antioxidant capacity, and modulating cecum microbiota.

Probing effects of site-specific aspartic acid isomerization on structure and stability of GB1 through chemical protein synthesis.

Chemical modifications of long-lived proteins, such as isomerization and epimerization, have been evoked as prime triggers for protein-damage related diseases. Deamidation of Asn residues, which results in formation of a mixture of l- and d-Asp and isoAsp via an intermediate aspartyl succinimide, can result in the disruption of cellular proteostasis and toxic protein depositions. In contrast to extensive data on the biological prevalence and functional implications of aspartyl succinimide formation, much less is known about the impact of the resulting altered backbone composition on properties of individual proteins at a molecular level. Here, we report the total chemical synthesis, biophysical characterization, and NMR structural analysis of a series of variants of the B1 domain of protein G from Streptococcal bacteria (GB1) in which all possible Asp isomers as well as an aspartyl succinimide were individually incorporated at a defined position in a solvent-exposed loop. Subtle local structural effects were observed; however, these were accompanied by notable differences in thermodynamic folded stability. Surprisingly, the noncanonical backbone connectivity of d-isoAsp led to a variant that exhibited enhanced stability relative to the natural protein.

Microbial responses and changes in metabolic products in bovine uteri infected with Staphylococcus aureus

There is mounting evidence that the uterine microbiota has an important role in the pathogenesis of endometritis, with invasion of pathogenic bacteria being a main cause of uterine microbial imbalance. However, mechanisms of uterine microbiota resistance to pathogen invasion remain unclear. In this study, an intrauterine infusion of Staphylococcus aureus was used as a bovine endometritis model; it significantly increased abundance of pathogenic bacteria (Streptococcus, Helccoccus, Fusobacterium, and Escherichia-Shigella) and significantly decreased abundance of probiotics (Allstipes, Bacteroides, Phascolarctobacterium, Romboutsia, and Prevotella). In addition, the metabolite aloe-emodin was positively correlated with Prevotella and based on combined analyses of omics and probiotics, the presence of its metabolite aloe-emodin in the uterus at least partially resisted Staphylococcus aureus invasion. Therefore, Aloe-emodin has potential for regulating microbial structure and preventing endometritis.

Prebiotic proanthocyanidins inhibit bile reflux-induced esophageal adenocarcinoma through reshaping the gut microbiome and esophageal metabolome.

The gut and local esophageal microbiome progressively shift from healthy commensal bacteria to inflammation-linked pathogenic bacteria in patients with gastroesophageal reflux disease, Barrett's esophagus, and esophageal adenocarcinoma (EAC). However, mechanisms by which microbial communities and metabolites contribute to reflux-driven EAC remain incompletely understood and challenging to target. Herein, we utilized a rat reflux-induced EAC model to investigate targeting the gut microbiome-esophageal metabolome axis with cranberry proanthocyanidins (C-PAC) to inhibit EAC progression. Sprague-Dawley rats, with or without reflux induction, received water or C-PAC ad libitum (700 μg/rat/day) for 25 or 40 weeks. C-PAC exerted prebiotic activity abrogating reflux-induced dysbiosis and mitigating bile acid metabolism and transport, culminating in significant inhibition of EAC through TLR/NF-κB/TP53 signaling cascades. At the species level, C-PAC mitigated reflux-induced pathogenic bacteria (Streptococcus parasanguinis, Escherichia coli, and Proteus mirabilis). C-PAC specifically reversed reflux-induced bacterial, inflammatory, and immune-implicated proteins and genes, including Ccl4, Cd14, Crp, Cxcl1, Il6, Il1b, Lbp, Lcn2, Myd88, Nfkb1, Tlr2, and Tlr4, aligning with changes in human EAC progression, as confirmed through public databases. C-PAC is a safe, promising dietary constituent that may be utilized alone or potentially as an adjuvant to current therapies to prevent EAC progression through ameliorating reflux-induced dysbiosis, inflammation, and cellular damage.

Inhibitory potential of turmeric extract (Curcuma domestica Val.) toward the growth of Streptococcus gordonii bacteria

Introduction: Dental caries is a disease caused by damage to the hard tissue of the teeth by the metabolic activity of bacteria, one of which is the cariogenic bacteria Streptococcus gordonii. Turmeric is one of the most popular spices in Asia with good antibacterial capabilities. Turmeric content such as curcumin can inhibit bacterial growth. Objective: To determine the potential inhibitory power of turmeric extract on the growth of Streptococcus gordonii. Method: The research is carried out using in vitro laboratory experimental analytical research with a posttest only control group design. The research determined the effect of turmeric extract concentrations of 50%, 12.5%, 3.125%, 0.78% against Streptococcus gordonii bacteria on agar media. Statistical data analysis is carried out to determine whether there was a significant effect of turmeric extract on the inhibition of the growth of Streptococcus gordonii bacteria in each treatment. Results: There was a significant influence on the test results between groups of turmeric extract concentration on the inhibitory power of Streptococcus gordonii bacteria. Conclusion: Turmeric extract can inhibit the growth of Streptococcus gordonii. Higher concentration of turmeric rhizome extract which can inhibit the growth of Streptococcus gordonii bacteria more effectively.

Diabetic Foot Ulcer on Coronavirus Patient

BACKGROUND: Corona virus (COVID 19) is an infection caused by a severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The manifestation is from mild symptoms to severe symptoms such as respiratory failure and death. The severity of symptoms that arises in COVID-19 patients is influenced by the comorbidities they have. One of the comorbidities is diabetes. Increasing blood viscosity and severe inflammation occur in the body of COVID-19 patients. Meanwhile, problems such as coagulation factors, body blood flow, disorders of the nerves, lowering the immune response also occur in diabetic patients and etc. One of the complications of diabetes that often occurs is diabetic foot ulcers. The wound will be aggravated by a bacterial infection, such as hemolytic Streptococcus. Delay in diabetic ulcer treatment increases the incidence of amputation, sepsis and death. One of the therapies for diabetic foot ulcer is negative pressure wound therapy (NPWT). NPWT has a higher total cure rate, shorter healing time, and fewer amputations. If the wound is large, it can be continued with Split-Thickness skin graft (STSGs). CASE REPORT: A-54-year-old male patient, moderately confirmed COVID 19 with diabetes Mellitus comorbidty and diabetic foot ulcer. Around the wound there was a black tissue the base of which were muscles and tendons. The tissue culture examination found hemolytic streptococcus bacteria. Diabetic ulcers are given antibiotic therapy, NPWT and STSG. After the patient had been discharged from the hospital and then examined by the surgical clinic, the wound was closed completely. CONCLUSION: Diabetes is also a comorbid COVID-19 infection. Patients who are infected with COVID-19 and have uncontrolled blood sugar will prolong the treatment period for diabetic foot ulcers and can improve amputation therapy. Negative-Pressure Wound Therapy (NPWT) is a tool that is often and effective used for wound management.

P193 Fatigued patients with Inflammatory Bowel Disease exhibit distinct systemic antibody epitope repertoires

Abstract Background Patients with inflammatory bowel diseases (IBD) frequently experience fatigue, affecting up to 80% of those with active disease and approximately 50% with quiescent disease. The exact cause of IBD-associated fatigue is often unknown, making clinical management very challenging. In this study we aimed to explore whether patients with quiescent IBD reporting fatigue exhibit specific systemic antibody responses, which could provide insight into immune reactivities underlying fatigue. Methods Systemic antibody epitope repertoires were profiled in 327 patients with IBD (156 Crohn’s disease [CD]; 171 ulcerative colitis [UC]) leveraging phage-display immunoprecipitation sequencing (PhIP-Seq) against 344,000 rationally selected peptide antigens. Fatigue severity was assessed on a 10-point Likert scale, ranging from 1 (no fatigue) to 10 (highest fatigue severity). Quiescent IBD was defined as clinical (Harvey-Bradshaw Index [HBI] &amp;lt;5 or Simple Clinical Colitis Activity Index [SCCAI] &amp;lt;2.5) and biochemical remission (C-reactive protein [CRP] &amp;lt;5 mg/L) at time of sampling. Multivariable logistic regression analyses, allowing adjustment for potential confounding factors e.g. age, sex, and smoking, were performed to identify associations between fatigue and systemic antibody responses. Results A total of 105 different antibody-bound peptides were associated with fatigue (nominal P-value&amp;lt;0.05), albeit none passed adjustment for multiple comparisons. Among these antibodies, 50 (47.6%) were found to be less frequent in highly fatigued patients (fourth quartile, Q4), while 55 (52.4%) were identified as more frequent in highly fatigued patients compared to those with low fatigue scores (first quartile, Q1). Among highly fatigued patients, antibody responses were primarily directed towards viral antigens, notably several antigens from Epstein-Barr virus (EBV), as well as bacterial antigens, including functional proteins from Streptococcus and Staphylococcus species. Fatigued patients with CD exhibited elevated systemic antibody responses against allergens, Staphylococcus, Pseudomonas aeruginosa, and Shigella spp. Fatigued patients with UC showed higher frequencies of antibody responses against herpes simplex virus (HSV), influenza viruses, and few responses against allergens and Streptococcus bacteria. These results remained materially unchanged when repeating analyses in patients with quiescent IBD. Conclusion This study may suggest a potential role of viral antigens, particularly EBV, in the pathophysiology of fatigue in patients with IBD. However, larger confirmatory studies are needed to validate these findings. PhIP-Seq may represent a valuable strategy to approach the investigation of immune responses underlying complex symptoms such as fatigue.

Dental composite biodeterioration in the presence of oral Streptococci and extracellular metabolic products

ObjectiveSecondary caries is a primary cause of early restoration failure. While primary dental caries has been extensively researched, our knowledge about the impact of secondary caries on dental restorations is relatively limited. In this study, we examined how different clinically relevant microbially-influenced environments impact the degradation of nano-filled (FIL) and micro-hybrid (AEL) dental composites. MethodsMaterial strength of two commercial dental composites was measured following incubation in aqueous media containing: i) cariogenic (Streptococcus mutans) and non-cariogenic bacteria (Streptococcus sanguinis) grown on sucrose or glucose, ii) abiotic mixtures of artificial saliva and sucrose and glucose fermentation products (volatile fatty acids and ethanol) in proportions known to be produced by these microorganisms, and iii) abiotic mixtures of artificial saliva and esterase, a common oral extracellular enzyme. ResultsNano-filled FIL composite strength decreased in all three types of incubations, while micro-hybrid AEL composite strength only decreased significantly in biotic incubations. The strength of both composites was statistically significantly decreased in all biotic incubations containing both cariogenic and non-cariogenic bacteria beyond that induced by either abiotic mixtures of fermentation products or esterase alone. Finally, there were no statistically significant differences in composite strength decrease among the tested biotic conditions. ConclusionsThe results show that conditions created during the growth of both cariogenic and non-cariogenic oral Streptococci substantially reduce commercial composite strength, and this effect warrants further study to identify the mechanism(s). Clinical SignificanceDental biofilms of oral Streptococci bacteria significantly affect the mechanical strength of dental restorations.

Homogeneity Gut microbiome Characteristics in Autoimmune Epithelitis: Primary Biliary Cholangitis and Primary Sjögren’s Syndrome.

Background : Accumulating studies had revealed that dysbiosis of the gut microbiome was involved in the occurrence and development of Primary biliary cholangitis (PBC) and Primary Sjögren’s syndrome (pSS). Aims : To examine the similarities and differences in gut microbiome as well as the relationship with pathogenesis in PBC and pSS. Methods : High throughput sequencing was conducted to analyze the 16S rDNA V3-V4 region of fecal microbial samples from 109 subjects including PBC (n=38), pSS (n=41) and healthy controls (HC, n=30) from the Affiliated Hospital of Qingdao University. The composition, diversity and markers of gut microbiome were compared between PBC, pSS and HC. Inter-group comparisons were conducted using analysis

Host-Guest Mechanism via Induced Fit Fullerene Complexation in Porphin Receptor to Probe Salivary Alpha-Amylase in Dental Caries for Clinical Applications.

Salivary α-amylase is the most abundant protein of human saliva that potentially binds to streptococcus and other bacteria via specific surface-exposed α-amylase-binding proteins and plays a significant role in caries development. The detection of α-amylase in saliva can be used as a bioindicator of caries development. Herein, a facile strategy has been applied, tailoring the photochemical properties of 5,10,15,20-tetrakis(4-hydroxyphenyl)-21H,23H-porphine (TPPOH) and the fullerene C60 complex. The fluorescence emission of TPPOH is quenched by starch-coated fullerene C60 via charge-transfer effects, as determined by UV absorption and fluorescence spectroscopic studies. The starch-coated C60 has been thoroughly characterized via Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), optical microscopy, thermal gravimetric analysis (TGA), static water contact angle measurements, and zeta potential measurements. The analytical response of the assay showed a linear fluorescent response in α-amylase concentrations ranging from 0.001-0.1 Units/mL, with an LOD of 0.001 Units/mL. The applicability of the method was tested using artificial saliva with quantitative recoveries in the range 95-100%. The practicability of the procedure was verified by inspecting saliva samples of real clinical samples covering all age groups. We believe that the proposed method can serve as an alternative analytical method for caries detection and risk assessment that would also minimize the cost of professional preventive measures and treatments.

Nine New Antibacterial Diterpenes and Steroids from the South China Sea Soft Coral Lobophytum catalai Tixier-Durivault.

Five new cembrane-type diterpenes, lobocalines A-E (1-5), and four new steroids, lobocaloids A-D (9-12), along with six known related compounds (6-8 and 13-15) were isolated from the Yalong Bay soft coral Lobophytum catalai Tixier-Durivault. The structures of the new compounds were elucidated by extensive spectroscopic analysis, NMR calculation with DP4+ analysis, time-dependent density functional theory-electronic circular dichroism (TDDFT-ECD) calculations, X-ray diffraction analyses and comparison with the reported spectroscopic data of known compounds. Further, with the aid of X-ray diffraction analysis, the structure of lobocrasol B (15) was firmly revised as 15a. In in vitro bioassays, compound 2 showed moderate antibacterial activities against fish pathogenic bacteria Streptococcus parauberis KSP28 and Phoyobacterium damselae FP2244 with minimum inhibitory concentration (MIC) values of 8.7 and 17.3 µg/mL, respectively. All the steroids exhibited antibacterial activities against the S. parauberis KSP28 with MIC values ranging from 12.3 to 53.6 µg/mL. Compounds 2, 7 and 14 have remarkable inhibitory effects on the hemolysin production of Staphylococcus aureus, while compounds 8-12 have medium inhibitory effects on the pyocyanin production in Pseudomonas aeruginosa.

Sensitivity of some types of Gr+ and Gr- bacteria to some types of commercial soaps

The use of soap is one of the most important means of ionic cleansing and getting rid of some types of bacteria that may be harmful and present on the skin, especially after using the toilet, as part of them may remain on the surface of the skin, causing some pathological injuries, and the ability of soap to remove or eliminate these germs varies according to the soap type and the period of its use in washing, the study aimed to determine the ability of some types of liquid soap to eliminate different types of Gram-positive and gram-negative bacteria. The plate method was used to find out the sensitivity of each of the types of bacteria(Klebsiella, E.coli Staph aureus, Pseudomonas, Streptococcus,) towards types of liquid soaps produced by international companies, including Bivy, Dettol, ActiveX, Lifebuoy, Oud, using the tablet method, and it was determined The minimum inhibitory concentration for each type of liquid soap (depending on the bacterial species used). Klebsiella E.coli showed high sensitivity to Dettol soap, while Pseudomonas and Staph aureus bacteria showed high sensitivity to Bivy soap. Streptococcus bacteria appeared to be highly sensitive to Lifebuoy soap, and the sensitivity of bacterial species to the rest of the soaps varied between medium and weak.

Antibacterial Effect of Starfruit Extract (Averrhoa blimbi L.) against Streptococcus mutans

Dental caries is caused by gram-positive bacteria Streptococcus mutans, which is part of the normal flora of the mouth. Herbal medicines have powerful antibacterial compounds that can be used to limit the growth of germs that cause infections. The aim of the research was to determine whether starfruit extract (Averrhoa blimbi L.) has antibacterial properties against Streptococcus mutans. This type of research uses a posttest only control group design in the laboratory. Streptococcus mutans in pure culture were used as the research sample. This study had two control groups, one with four repetitions of DMSO as a negative control and one with a positive control (0.2% chlorhexidine), and four treatment groups with starfruit extract concentrations (20%, 40%, 60%, and 80 %). The disc diffusion method was used to test the antibacterial effect. One-way ANOVA and post hoc LSD statistical tests were then used to test the results. The results showed that, for Streptococus mutans bacteria, the mean and standard deviation of the diameter of the inhibition zone of starfruit extract at concentrations of 20%, 40%, 60%, and 80% were 12.03 ± 0.33 mm, 16.70 ± 0, 48 mm, 19.98 ± 0.13 mm, 22.25 ± 0.26 mm, and 19.25 ± 0.91 mm in the positive control, but no zone of inhibition was observed in the negative control. The width of the inhibition zone in starfruit extract (Averrahoa blimbi L.) at doses of 20%, 40%, 60%, 80%, positive control, and negative control was significantly different, according to the results of the one-way ANOVA test (p=0.000; p≤ 0.05). Antibacterial efficacy against Streptococcus mutans varied significantly (p≤0.05) among all star fruit extract groups and positive and negative controls, based on LSD post hoc test findings. Based on the research results, it can be said that star fruit extract at the most effective concentration, namely 80%, has antibacterial properties against Streptococcus mutans.

Microbes on the "peachy spots" of ancient Kaihua paper: microbial community and functional analysis.

Kaihua paper is a type of precious hand-made paper in China that has been used throughout Chinese history. Due to its extraordinary whiteness and fine texture, it was adopted by the imperial palace in the reign of Emperor Kang Xi and Yong Zheng of the Qing Dynasty of China in the 17th and 18th century. It is stained by a special type of yellowish-brown spot after years of storage, which is called a "peachy spot." The formation of such spots remains unclear, although complicated physicochemical processes or microbial activities might be involved. We performed nondestructive sampling and high-throughput sequencing on peachy spot surfaces, unstained areas, and air samples in the stack room to analysis the the bacterial and fungal communities, and performed prediction of functional genes of the bacterial communities. The results showed that peachy spot formation was mainly related to bacterial communities rather than fungal communities. Significantly more potential acid- producing, acidophilic or cellulase-producing bacteria, such as, Streptococcus, Staphylococcus, and Lysinibacillus, and pigment-producing bacteria, such as Methylobacterium and Rubrobacter, were identified in the peachy spot samples. Prediction of the functional genes of the bacterial community also suggested the production of acidic substance pigments. These findings provide new insights into the pigment formation mechanism in ancient paper and open an opportunity to develop new strategies to preserve the ancient paper documents.

Effects of sodium selenite, cysteamine, bacterially synthesized Se-NPs, and cysteamine loaded on Se-NPs on ram sperm cryopreservation

During the cryopreservation of sperm, the production of highly reactive oxygen species (ROS) can reduce their viability and fertility. However, the addition of antioxidants can help reduce the harmful effects of ROS. One such antioxidant is selenium, which is a co-factor of the glutathione peroxidase enzyme that is effective in scavenging ROS. Cysteamine can also take part in the structure of this enzyme. The use of nanoparticles can be less toxic to cells than their salt form. To this end, researchers synthesized Se-NPs using the streptococcus bacteria and loaded cysteamine onto the synthesized Se-NPs. The biosynthesis of Se-NPs and cysteamine loaded on Se-NPs was confirmed by UV–visible spectroscopy, X-ray diffraction (EDX), Fourier transforms infrared (FTIR) spectroscopy, and Field Emission Scanning Electron Microscope (FE-SEM). For cryopreservation, ram semen samples were diluted, and different concentrations (0, 1, 5, 25, and 125 µg/mL) of cysteamine, Se-NPs, cysteamine loaded on Se-NPs, and sodium selenite were added. An extender containing no supplement was considered as control group. After cooling the semen samples, they were frozen and stored in liquid nitrogen for evaluation. The samples were thawed and analyzed for mobility, viability, membrane and DNA integrity, and sperm abnormalities, as well as malondialdehyde level (MDA) and superoxide dismutase (SOD). The data was processed using SPSS, and a significance level of p < 0.05 was considered. The results of this experiment showed that adding 1 μg/mL of cysteamine loaded on Se-NPs to the diluent significantly increased the motility, viability, and membrane integrity and SOD of spermatozoa compared to the other treatment groups and control group, and reduced the abnormality, apoptosis, and MDA level of spermatozoa in comparison with the other treatment groups and control group (p < 0.05). In conclusion, the addition of cysteamine loaded on Se-NPs was found to improve the quality of ram sperm after cryopreservation.

In silico approaches for predicting natural compounds with therapeutic potential and vaccine candidates against Streptococcus equi

Equine strangles is a prevalent disease that affects the upper respiratory in horses and is caused by the Gram-positive bacterium Streptococcus equi. In addition to strangles, other clinical conditions are caused by the two S. equi subspecies, equi and zooepidemicus, which present relevant zoonotic potential. Treatment of infections caused by S. equi has become challenging due to the worldwide spreading of infected horses and the unavailability of effective therapeutics and vaccines. Penicillin treatment is often recommended, but multidrug resistance issues arised. We explored the whole genome sequence of 18 S. equi isolates to identify candidate proteins to be targeted by natural drug-like compounds or explored as immunogens. We considered only proteins shared among the sequenced strains of subspecies equi and zooepidemicus, absent in the equine host and predicted to be essential and involved in virulence. Of these, 4 proteins with cytoplasmic subcellular location were selected for molecular docking with a library of 5008 compounds, while 6 proteins were proposed as prominent immunogens against S. equi due to their probabilities of behaving as adhesins. The molecular docking analyses revealed the best ten ligands for each of the 4 drug target candidates, and they were ranked according to their binding affinities and the number of hydrogen bonds for complex stability. Finally, the natural 5-ring compound C25H20F3N5O3 excelled in molecular dynamics simulations for the increased stability in the interaction with UDP-N-acetylenolpyruvoylglucosamine reductase (MurB). This research paves the way to developing new therapeutics to minimize the impacts caused by S. equi infections. Communicated by Ramaswamy H. Sarma

In vitro evaluation of the application of an optimized xylanase cocktail for improved monogastric feed digestibility.

Xylanases from glycoside hydrolase (GH) families 10 and 11 are common feed additives for broiler chicken diets due to their catalytic activity on the nonstarch polysaccharide xylan. This study investigated the potential of an optimized binary GH10 and GH11 xylanase cocktail to mitigate the antinutritional effects of xylan on the digestibility of locally sourced chicken feed. Immunofluorescence visualization of the activity of the xylanase cocktail on xylan in the yellow corn of the feed showed a substantial collapse in the morphology of cell walls. Secondly, the reduction in the viscosity of the digesta of the feed by the cocktail showed an effective degradation of the soluble fraction of xylan. Analysis of the xylan degradation products from broiler feeds by the xylanase cocktail showed that xylotriose and xylopentaose were the major xylooligosaccharides (XOS) produced. In vitro evaluation of the prebiotic potential of these XOS showed that they improved the growth of the beneficial bacteria Streptococcus thermophilus and Lactobacillus bulgaricus. The antibacterial activity of broths from XOS-supplemented probiotic cultures showed a suppressive effect on the growth of the extraintestinal infectious bacterium Klebsiella pneumoniae. Supplementing the xylanase cocktail in cereal animal feeds attenuated xylan's antinutritional effects by reducing digesta viscosity and releasing entrapped nutrients. Furthermore, the production of prebiotic XOS promoted the growth of beneficial bacteria while inhibiting the growth of pathogens. Based on these effects of the xylanase cocktail on the feed, improved growth performance and better feed conversion can potentially be achieved during poultry rearing.

Critical evaluation of silver nanoparticles synthesized at room temperature/microwave irradiation: A green approach

Biological routes of nanoparticle synthesis, especially the use of plant-based extracts, have shown great potential for the production of silver nanoparticles (Ag NPs). Ag NPs synthesized in this way is a simple one-step method that is economical and environmentally friendly. With the increasing need to develop new and effective antibacterial agents, a novel and stable Ag NPs is synthesized using aqueous seed extract of Strychnos potatorum (SP). Ag NPs obtained at room temperature (S1) and under optimal microwave irradiation (S2) were compared in the present work. The as-synthesized Ag NPs are characterized by Ultraviolet-Visible (UV-Vis) spectroscopy, X-Ray Diffraction (XRD), Fourier Transform Infrared (FT-IR) spectroscopy, Field Emission Scanning Electron Microscopy (FESEM) and Transmission Electron Microscopy (TEM). UV-Vis spectra showed Surface Plasmon Resonance (SPR) peaks at 430nm (S1) and 438nm (S2) associated with the formation of Ag NPs. XRD patterns indicate the crystallinity of Ag NPs, with an average crystallite size of approximately 23nm (S1) and 15nm (S2). FT-IR study revealed potential biomolecules to form Ag NPs. FESEM and TEM analysis revealed the spherical shape of Ag NPs. An average particle size of approximately 31nm (S1) and 19nm (S2) was revealed from TEM analysis. To the best of our understanding, this study is novel as Ag NPs synthesized from SP using a microwave oven are described in detail for the first time. The study also demonstrated the potential of Ag NPs for antibacterial effect against Gram-positive bacteria (Streptococcus pneumoniae, Staphylococcus aureus) and Gram-negative bacteria (Klebsiella pneumoniae, Vibrio vulnificus). Our findings show that at a specific concentration, small NPs are more efficient in inhibiting bacterial activity. This research indicates that Ag NPs synthesized from SP exhibit strong antibacterial activity for the treatment of bacterial infection.

Lacticaseibacillus casei- and Bifidobacterium breve-fermented red pitaya promotes beneficial microbial proliferation in the colon.

Red pitaya has been demonstrated to strongly inhibit α-glucosidase activity; however, the impact of red pitaya fermentation by probiotic bacteria on α-glucosidase inhibition remains unclear. In this study, six strains of lactic acid bacteria (Lactiplantibacillus plantarum, Lacticaseibacillus rhamnosus, Lactobacillus bulgaricus, Lacticaseibacillus casei, Lactobacillus acidophilus and Streptococcus thermophilus) and one strain of Bifidobacterium breve were utilized for the fermentation of red pitaya pulp. The α-glucosidase and α-amylase inhibition rates of red pitaya pulp were significantly greater after fermentation by Bifidobacterium breve and Lacticaseibacillus casei than by the other abovementioned strains. The LC group exhibited an α-glucosidase inhibition rate of 99%, with an α-amylase inhibition rate of 89.91%. In contrast, the BB group exhibited an α-glucosidase inhibition rate of 95.28%, accompanied by an α-amylase inhibition rate of 95.28%. Moreover, red pitaya pulp fermented with Bifidobacterium breve and Lacticaseibacillus casei produced a notable quantity of oligosaccharides, which was more than three times greater than that in the other groups. Furthermore, 16S rRNA high-throughput sequencing analysis was conducted to assess alterations in the composition of the gut microbiota. This revealed an increase in the abundance of Lactobacillus and Faecalibacterium in the pulp fermented by Bifidobacterium breve and Lacticaseibacillus casei, whereas the abundance of Sutterella decreased. Further analysis at the species level revealed that Bifidobacterium longum, Faecalibacterium prausnitzii, and Lactobacillus zeae were the dominant strains present during colonic fermentation. These results indicate a beneficial health trend associated with probiotic bacterial fermentation of red pitaya pulp, which is highly important for the development of functional products.

Antibacterial effect of resveratrol extract compared to chlorhexidine mouthwash against primary cariogenic pathogen, Streptococcus mutans.

Modern dental caries prevention methods have focused on using herbal products that ideally inhibit the critical cariogenic bacteria (Streptococcus mutans). The present study compared antibacterial efficacy of the resveratrol herbal extract and 0.12% chlorhexidine (CHX) against Streptococcus mutans (S. mutans). In this in vitro study the pure powder of resveratrol (Bulksupplement) was dissolved in dimethyl sulfoxide as its solvent to produce a 1000-µg/mL concentration of resveratrol solution, which was later used at different dilutions. The antibacterial effects of resveratrol solution and 0.12% CHX mouthrinse on the standard strain of S. mutans were determined using a minimum inhibitory concentration (MIC) test in a tube, minimum bactericidal concentration (MBC) test in a solid medium, and a well diffusion test to measure the zone of inhibition. The data were analyzed using Kruskal-Wallis, Bonferroni, and Man-Whitney tests (α=0.05). The MIC and MBC of resveratrol was 250 µg/mL. In addition, this extract exhibited a diameter of 6.67 mm for the inhibition zone at only the 1000-µg/mL concentration. The MIC of CHX was 15.6 µg/mL, and its MBC was 31.25 µg/mL. The highest growth inhibition zone of CHX was 16.67 mm. Resveratrol extract exhibited a dose-dependent antibacterial (bacteriostatic and bactericidal) activity against S. mutans. Although it was not as effective as CHX, it might be a suitable alternative to prevent dental caries. Key words:Antibacterial agents, Chlorhexidine digluconate, mouthwashe, resveratrol, streptococcus mutans.