Novel Exopolysaccharide from Marine Bacillus subtilis with Broad Potential Biological Activities: Insights into Antioxidant, Anti-Inflammatory, Cytotoxicity, and Anti-Alzheimer Activity

In the presented study, Bacillus subtilis strain AG4 isolated from marine was identified based on morphological, physiological, phylogenetic characteristics and an examination of 16S rRNA sequences. Novel exopolysaccharide (EPSR4) was extracted and isolated from the Bacillus subtilis strain as a major fraction of exopolysaccharide (EPS). The analysis of structural characterization indicated that EPSR4 is a β-glycosidic sulphated heteropolysaccharide (48.2%) with a molecular weight (Mw) of 1.48 × 104 g/mole and has no uronic acid. Analysis of monosaccharide content revealed that EPSR4 consists of glucose, rhamnose and arabinose monosaccharide in a molar ratio of 5:1:3, respectively. Morphological analysis revealed that EPSR4 possess a high crystallinity degree with a significant degree of porosity, and its aggregation and conformation in the lipid phase might have a significant impact on the bioactivity of EPSR4. The biological activity of EPSR4 was screened and evaluated by investigating its antioxidant, cytotoxicity, anti-inflammatory, and anti-Alzheimer activities. The antioxidant activity results showed that EPSR4 has 97.6% scavenging activity toward DPPH free radicals at 1500 µg/mL, with an IC50 value of 300 µg/mL, and 64.8% at 1500 µg/mL toward hydrogen peroxide free radicals (IC50 = 1500 µg/mL, 30 min). Furthermore, EPSR4 exhibited considerable inhibitory activity towards the proliferation of T-24 (bladder carcinoma), A-549 (lung cancer) and HepG-2 (hepatocellular carcinoma) cancer cell lines with IC50 of 244 µg/mL, 148 µg/mL and 123 µg/mL, respectively. An evaluation of anti-inflammatory activity revealed that EPSR4 has potent lipoxygenase (LOX) inhibitory activity (IC50 of 54.3 µg/mL) and a considerable effect on membrane stabilization (IC50 = 112.2 ± 1.2 µg/mL), while it showed cyclooxygenase (COX2) inhibitory activity up to 125 µg/mL. Finally, EPSR4 showed considerable inhibitory activity towards acetylcholine esterase activity. Taken together, this study reveals that Bacillus subtilis strain AG4 could be considered as a potential natural source of novel EPS with potent biological activities that would be useful for the healthcare system.Faculty of Science, Suez Canal UniversityPrincess Nourah bint Abdulrahman UniversityTaif UniversityPeer Reviewe

Hybrid multicriteria fuzzy classification of network traffic patterns, anomalies, and protocols

© 2017, Springer-Verlag London Ltd., part of Springer Nature. Traffic classification in computer networks has very significant roles in network operation, management, and security. Examples include controlling the flow of information, allocating resources effectively, provisioning quality of service, detecting intrusions, and blocking malicious and unauthorized access. This problem has attracted a growing attention over years and a number of techniques have been proposed ranging from traditional port-based and payload inspection of TCP/IP packets to supervised, unsupervised, and semi-supervised machine learning paradigms. With the increasing complexity of network environments and support for emerging mobility services and applications, more robust and accurate techniques need to be investigated. In this paper, we propose a new supervised hybrid machine-learning approach for ubiquitous traffic classification based on multicriteria fuzzy decision trees with attribute selection. Moreover, our approach can handle well the imbalanced datasets and zero-day applications (i.e., those without previously known traffic patterns). Evaluating the proposed methodology on several benchmark real-world traffic datasets of different nature demonstrated its capability to effectively discriminate a variety of traffic patterns, anomalies, and protocols for unencrypted and encrypted traffic flows. Comparing with other methods, the performance of the proposed methodology showed remarkably better classification accuracy

Carrier-envelope phase stable, 5.4 μJ, broadband, mid-infrared pulse generation from a 1-ps, Yb:YAG thin-disk laser

We report on a simple scheme to generate broadband, μJ pulses centered at 2.1 μm with an intrinsic carrier-envelope phase (CEP) stability from the output of a Yb:YAG regenerative amplifier delivering 1-ps pulses with randomly varying CEP. To the best of our knowledge, the reported system has the highest optical-to-optical efficiency for converting 1-ps, 1 μm pulses to CEP stable, broadband, 2.1 μm pulses. The generated coherent light carries an energy of 5.4 μJ, at 5 kHz repetition rate, that can be scaled to higher energy or power by using a suitable front end, if required. The system is ideally suited for seeding broadband parametric amplifiers and multichannel synthesizers pumped by picosecond Yb-doped amplifiers, obviating the need for active timing synchronization. Alternatively, this scheme can be combined with high-power oscillators with tens of μJ energy to generate CEP stable, multioctave supercontinua, suitable for field-resolved and time-resolved spectroscopy

SjClust: A Framework for Incorporating Clustering into Set Similarity Join Algorithms

A critical task in data cleaning and integration is the identification of duplicate records representing the same real-world entity. Similarity join is largely used in order to detect pairs of similar records in combination with a subsequent clustering algorithm for grouping together records referring to the same entity. Unfortunately, the clustering algorithm is strictly used as a post-processing step, which slows down the overall performance, and final results are produced at the end of the whole process only. Inspired by this critical evidence, in this article we propose and experimentally evaluate SjClust, a framework to integrate similarity join and clustering into a single operation. The basic idea of our proposal consists in introducing a variety of cluster representations that are smoothly merged during the set similarity task carried out by the join algorithm. An optimization task is further applied on top of such framework. Experimental results derived from an extensive experimental campaign show that we outperform previous approaches by an order of magnitude in most settings

Binding Studies of Caffeic and p-Coumaric Acid with α-Amylase: Multispectroscopic and Computational Approaches Deciphering the Effect on Advanced Glycation End Products (AGEs)

Alpha-amylase (α-amylase) is a key player in the management of diabetes and its related complications. This study was intended to have an insight into the binding of caffeic acid and coumaric acid with α-amylase and analyze the effect of these compounds on the formation of advanced glycation end-products (AGEs). Fluorescence quenching studies suggested that both the compounds showed an appreciable binding affinity towards α-amylase. The evaluation of thermodynamic parameters (ΔH and ΔS) suggested that the α-amylase-caffeic/coumaric acid complex formation is driven by van der Waals force and hydrogen bonding, and thus complexation process is seemingly specific. Moreover, glycation and oxidation studies were also performed to explore the multitarget to manage diabetes complications. Caffeic and coumaric acid both inhibited fructosamine content and AGE fluorescence, suggesting their role in the inhibition of early and advanced glycation end-products (AGEs). However, the glycation inhibitory potential of caffeic acid was more in comparison to p-coumaric acid. This high antiglycative potential can be attributed to its additional –OH group and high antioxidant activity. There was a significant recovery of 84.5% in free thiol groups in the presence of caffeic acid, while coumaric attenuated the slow recovery of 29.4% of thiol groups. In vitro studies were further entrenched by in silico studies. Molecular docking studies revealed that caffeic acid formed six hydrogen bonds (Trp 59, Gln 63, Arg 195, Arg 195, Asp 197 and Asp 197) while coumaric acid formed four H-bonds with Trp 59, Gln 63, Arg 195 and Asp 300. Our studies highlighted the role of hydrogen bonding, and the ligands such as caffeic or coumaric acid could be exploited to design antidiabetic drugs

Elucidation of the Metabolite Profile of Yucca gigantea and Assessment of Its Cytotoxic, Antimicrobial, and Anti-Inflammatory Activities

The acute inflammation process is explained by numerous hypotheses, including oxidative stress, enzyme stimulation, and the generation of pro-inflammatory cytokines. The anti-inflammatory activity of Yucca gigantea methanol extract (YGME) against carrageenan-induced acute inflammation and possible underlying mechanisms was investigated. The phytochemical profile, cytotoxic, and antimicrobial activities were also explored. LC-MS/MS was utilized to investigate the chemical composition of YGME, and 29 compounds were tentatively identified. In addition, the isolation of luteolin-7-O-β-d-glucoside, apigenin-7-O-β-d-glucoside, and kaempferol-3-O-α-l-rhamnoside was performed for the first time from the studied plant. Inflammation was induced by subcutaneous injection of 100 μL of 1% carrageenan sodium. Rats were treated orally with YGME 100, 200 mg/kg, celecoxib (50 mg/kg), and saline, respectively, one hour before carrageenan injection. The average volume of paws edema and weight were measured at several time intervals. Levels of NO, GSH, TNF-α, PGE-2, serum IL-1β, IL-6 were measured. In additionally, COX-2 immunostaining and histopathological examination of paw tissue were performed. YGME displayed a potent anti-inflammatory influence by reducing paws edema, PGE-2, TNF-α, NO production, serum IL-6, IL-1β, and COX-2 immunostaining. Furthermore, it replenished the diminished paw GSH contents and improved the histopathological findings. The best cytotoxic effect of YGME was against human melanoma cell line (A365) and osteosarcoma cell line (MG-63). Moreover, the antimicrobial potential of the extract was evaluated against bacterial and fungal isolates. It showed potent activity against Gram-negative, Gram-positive, and fungal Candida albicans isolates. The promoting multiple effects of YGME could be beneficial in the treatment of different ailments based on its anti-inflammatory, antimicrobial, and cytotoxic effects

Promising Antiviral Activity of Agrimonia pilosa Phytochemicals against Severe Acute Respiratory Syndrome Coronavirus 2 Supported with In Vivo Mice Study

The global emergence of the COVID-19 pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has focused the entire world’s attention toward searching for a potential remedy for this disease. Thus, we investigated the antiviral activity of Agrimonia pilosa ethanol extract (APEE) against SARS-CoV-2 and it exhibited a potent antiviral activity with IC50 of 1.1 ± 0.03 µg/mL. Its mechanism of action was elucidated, and it exhibited a virucidal activity and an inhibition of viral adsorption. Moreover, it presented an immunomodulatory activity as it decreased the upregulation of gene expression of COX-2, iNOS, IL-6, TNF-α, and NF-κB in lipopolysaccharide (LPS)-induced peripheral blood mononuclear cells. A comprehensive analysis of the phytochemical fingerprint of APEE was conducted using LC-ESI-MS/MS technique for the first time. We detected 81 compounds and most of them belong to the flavonoid and coumarin classes. Interestingly, isoflavonoids, procyanidins, and anthocyanins were detected for the first time in A. pilosa. Moreover, the antioxidant activity was evidenced in DPPH (IC50 62.80 µg/mL) and ABTS (201.49 mg Trolox equivalents (TE)/mg) radical scavenging, FRAP (60.84 mg TE/mg), and ORAC (306.54 mg TE/g) assays. Furthermore, the protective effect of APEE was investigated in Lipopolysaccharides (LPS)-induced acute lung injury (ALI) in mice. Lung W/D ratio, serum IL-6, IL-18, IL-1β, HO-1, Caspase-1, caspase-3, TLR-4 expression, TAC, NO, MPO activity, and histopathological examination of lung tissues were assessed. APEE induced a marked downregulation in all inflammation, oxidative stress, apoptosis markers, and TLR-4 expression. In addition, it alleviated all histopathological abnormalities confirming the beneficial effects of APEE in ALI. Therefore, APEE could be a potential source for therapeutic compounds that could be investigated, in future preclinical and clinical trials, in the treatment of patients with COVID-19