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Akter, R.

Publications and source records attributed to Akter, R..

5 recordsLinked to original sources

Phytochemical and Therapeutic Evaluation of Ficus nervosa Leaves: Impact on Oxidative Stress, Analgesic, Diarrhea, and Blood Clotting in a Mice Model

BackgroundFicus nervosa (FN) leaves have been traditionally used in ethnomedicine for the treatment of various ailments, this study aimed to investigate the cold methanol extract of FN for its antioxidant, analgesic, antidiarrheal, and thrombolytic properties, along with preliminary phytochemical screening to identify key bioactive compounds and acute toxicity test to assess the safety profile of the extract. MethodsIn this study, we conducted an initial investigation to identify the major phytochemical groups present in the leaves of Ficus nervosa. Using conventional phytochemical screening methods on cold methanol extracts, we consistently identified phenols and flavonoids as the predominant bioactive compounds. Following this phytochemical characterization, we assessed the biological activities of the extracts across multiple models. The antioxidant capacity and free radical-scavenging ability of the leaves extracts were evaluated using the DPPH (2,2-Diphenyl-1-picrylhydrazyl) assay. Analgesic efficacy was assessed through acetic acid-induced writhing and electrically induced heat nociception tests. Antidiarrheal effects were examined using castor oil-induced diarrhea and an enteropooling assay in mice. To determine thrombolytic activity, we conducted a human blood clot lysis assay, while preclinical toxicity testing was conducted to evaluate the safety profile of the extracts. Statistical analysis was performed using one-way ANOVA with Duncans Multiple Range Test (DMRT) to validate the significance of the results. ResultsThe study of Antioxidant Potential, the ESFs (ethyl soluble fraction) antioxidant capacity, measured at 409.91 {+/-} 0.59 mg of ascorbic acid equivalent (AAE)/g in the phosphomolybdenum assay, signifies a strong free radical scavenging activity. This level of antioxidant action, alongside a potent free radical neutralizing concentration (IC of 9.99 {+/-} 0.41 g/mL), suggests that the ESF could effectively counteract oxidative stress. Analgesic activity at 500 mg/kg, FN extract produced a 68.05% suppression of writhing in mice, which was statistically significant (p<0.001) compared to standard morphines (74.05%) inhibition. The extract also significantly prolonged reaction latency to thermal-induced pain in hotplate model. The antidiarrheal activity showed 52.09% and 59.0% suppression of defecation, compared to standard loperamides 73.1%, with statistically significant p-values (p<0.04 and p<0.01). These effects, combined with the notable decrease in intestinal fluid accumulation and defecation frequency in enteropooling assays, indicate that FN extract might interact with intestinal motility or fluid secretion pathways, providing antidiarrheal benefits. Additionally, the chloroform-soluble fraction of FN exhibited moderate thrombolytic activity, achieving 39.79% clot lysis compared to streptokinase (69.52%). Although this thrombolytic potential is moderate, it indicates that the fraction contains compounds with some fibrinolytic properties, which could be useful as adjunctive agents in preventing thrombosis. ConclusionOverall, the cold methanol extract of FN leaves demonstrates the therapeutic potential in preclinical settings. Future research is warranted to isolate the specific bioactive compounds and explain their mechanisms of action to further support the development of new treatments and contributing to modern medicinal practices based on this plant leaves.

plant biology↗

Isolation, Characterization, and Identification of Nitrogen Fixing Bacteria from Rhizosphere of Sonneratia apetala Collected from Sundarbans

Nitrogen is a crucial element for plant growth, driving vibrant greenery, photosynthesis, and overall vitality. This research focused on isolating, characterizing, and identifying nitrogen-fixing bacteria from the rhizosphere of Sonneratia apetala in the Sundarbans, Khulna, Bangladesh, with the goal of assessing their potential as biofertilizers. Despite the Sundarbans rich microbial diversity, less than 5-10% of species have been identified due to challenges in culturing, which has limited exploration of their applications. In this study, nitrogen-fixing bacteria were isolated using nitrogen-free media, including yeast extract mannitol agar(YEMA) and Burks media, followed by an ammonification test to select ammonia-producing bacteria. This process yielded ten nitrogen-fixing bacterial isolates capable of producing indole-3-acetic acid (IAA). Various biochemical tests, including oxidase, catalase, methyl red, indole, urease, citrate, triple sugar iron, and starch hydrolysis, were conducted. The isolates, designated AK1 to AK10, were identified as Rossellomorea sp., Clostridium sp., Achromobacter sp., Pseudomonas sp., Gluconacetobacter sp., Scytonema sp., Pseudomonas sp., Nesterenkonia sp., Gluconacetobacter sp., and Bacillus sp., respectively. Additionally, isolates AK1, AK3, AK4, and AK10 were confirmed through 16S rRNA sequencing. A pot test further revealed that isolate AK-1 significantly stimulated the growth and development of maize seedlings. Future studies are needed to examine the impact of these bacterial isolates on crop yield and seed quality, to better determine their suitability as biofertilizers.

microbiology↗

Assembly and performance of a cholera RDT prototype that detects both Vibrio cholerae and associated bacteriophage as a proxy for pathogen detection

IntroductionCholera rapid diagnostic tests (RDTs) are vulnerable to virulent bacteriophage predation. We hypothesized that an enhanced cholera RDT that detects the common virulent bacteriophage ICP1 might serve as a proxy for pathogen detection. We previously developed a monoclonal antibody (mAb) to the ICP1 major capsid protein. Our objective herein was to design and assemble a first-of-its-kind RDT that detects both a bacterial pathogen (Vibrio cholerae) and associated virulent bacteriophage (ICP1). MethodCandidate mAbs were expanded to increase design options and evaluated by immunological assays (ELISA; western blot). A subset of mAbs were selected for gold conjugation and printing on the RDT. The limit of detection (LOD) of prototype RDTs were determined in diarrheal stools with the addition of ICP1. ResultsThree mAb candidates were developed and evaluated for the capsid decoration protein (ORF123) and tail fiber protein (ORF93), and the prior mAb for the major capsid protein (ORF122). A single mAb sandwich RDT prototype for ORF122 was able to detect ICP1; RDTs with mAbs to ORF123 and ORF93 failed to detect ICP1 in single or dual sandwich configurations. Biologically meaningful LODs for ICP1 were achieved only after boiling the stool with ICP1; analysis by electron microscopy suggested increased epitope availability after boiling. ConclusionIn this study, we demonstrate a proof of concept for a functional RDT that can detect both the primary pathogen and a common virulent bacteriophage as a proxy for pathogen detection. Further optimization is required before scaled production and implementation.

immunology↗

In-vivo evaluation of the anti-diarrheal effect of Lactococcus lactis subspecies lactis and Lactococcus piscium isolated from yogurt.

Lactobacillus and Lactococcus species found in the yogurt of different sources are most widely assayed and used all over the world as a probiotic agent. This study aimed to isolate and identify novel probiotic agents with therapeutic value against diarrhea. Initially, the probiotic properties of the isolated lactic acid bacteria from the yogurt samples of the Chittagong division, Bangladesh, were evaluated. All probiotic candidates inhibited the growth of selected pathogens, including Escheriachia coli, Serratia sp. Salmonella paratyphi, Streptococcus Group-B, Staphylococcus aureus, Haemophillus influenzae, Bacillus subtillis, and Klebsiella pneumoniae. Lactococcus lactis subsp lactis were found most useful in inhibiting all the selected pathogens. When the probiotics were applied against castor oil-induced diarrhea in the rat model, Lactococcus lactis subspecies lactis and Lactococcus piscium were found significantly effective relative to the controls indicating their potentiality as an alternative therapeutic against diarrhea. HighlightsO_LILactococcus lactis subspecies lactis and Lactococcus piscium has shown potentiality to be a therapeutic agent against castor-oil induced diarrhea in an animal model. C_LIO_LILactococcus lactis subspecies lactis and Lactococcus piscium inhibited the growth of specified pathogens. C_LI

microbiology↗

Conglomeration of highly antigenic nucleoproteins to inaugurate a heterosubtypic next generation vaccine candidate against Arenaviridae family

AbstractArenaviral infections often resulting in lethal Hemorrhagic Fevers (HF) affect primarily African and South American regions. To date, there is no FDA-approved licensed vaccine against arenaviruses and treatments have been limited to supportive therapies. Hence, the study was employed to design a highly immunogenic heterosubtypic vaccine candidate against Arenaviridae family. The whole proteomes of Lassa virus (LASV), Lymphocytic Chorio Meningitis Virus (LCMV), Lujo virus and Guanarito virus were retrieved from NCBI database and assessed to determine the most antigenic viral proteins. Only the conserved sequences were used for T cell and B cell epitope prediction to ensure protective response against a wide range of viral strains. For each virus, nucleoproteins were identified as most antigenic which generated a plethora of antigenic epitopes. The proposed epitopes were highly conserved (up to 100%) and showed high cumulative population coverage. Moreover, results revealed that among the top epitopes, T cell epitope GWPYIGSRS were conserved in Argentine mammarenavirus (Junin virus) and Brazilian mammarenavirus (Sabia virus), while B cell epitope NLLYKICLSG were conserved in Bolivian mammarenavirus (Machupo virus) and Brazilian mammarenavirus (Sabia virus), indicating the possibility of final vaccine constructs to confer broad range immunity in the host. A total 3 constructs were designed by the combination of top epitopes from each protein along with suitable adjuvant and linkers. Different physicochemical properties revealed the superiority of construct V1 in terms of safety and efficacy. Docking analysis of the refined vaccine structure with different MHC molecules and human immune receptors were also biologically significant. The vaccine receptor complex (V1-TLR3) showed minimal deformability at molecular level. Moreover, construct V1 was compatible for insertion into pET28a(+) vector and heterologous cloning in E. coli srain K12. However, the results were based on different sequence analysis and various immune databases. Further wet lab based studies using model animals are highly recommended for the experimental validation of the designed vaccine candidates.

bioinformatics↗