Seaweeds and Corals from the Brazilian Coast: Review on Biotechnological Potential and Environmental Aspects.

Brazil has a megadiversity that includes marine species that are distributed along 800 km of shoreline. This biodiversity status holds promising biotechnological potential. Marine organisms are important sources of novel chemical species, with applications in the pharmaceutical, cosmetic, chemical, and nutraceutical fields. However, ecological pressures derived from anthropogenic actions, including the bioaccumulation of potentially toxic elements and microplastics, impact promising species. This review describes the current status of the biotechnological and environmental aspects of seaweeds and corals from the Brazilian coast, including publications from the last 5 years (from January 2018 to December 2022). The search was conducted in the main public databases (PubChem, PubMed, Science Direct, and Google Scholar) and in the Espacenet database (European Patent Office-EPO) and the Brazilian National Property Institute (INPI). Bioprospecting studies were reported for seventy-one seaweed species and fifteen corals, but few targeted the isolation of compounds. The antioxidant potential was the most investigated biological activity. Despite being potential sources of macro- and microelements, there is a literature gap regarding the presence of potentially toxic elements and other emergent contaminants, such as microplastics, in seaweeds and corals from the Brazilian coast.

Polysaccharides Produced by Microalgae

The class of polysaccharides is recognized to be of paramount importance in modern technology;the possible molecular chemodiversity of these biomaterials that can be found in microalgae can play an important role in industrial sectors such as food, pharmaceutical, cosmetic, nutraceutical, and aquaculture. Some species of microalgae are already commercially available and studies about their bioculturing are advanced, thus offering high-value products for commercial applications. In this chapter the results of a searching the literature from 2013 to 2019 has been conducted on the structural identification and characterization of polysaccharides from these microorganisms. This report has been restricted to species commercially available, which are well known and prone to possible utilization and will not cover any possible discovery about rare or new species. In addition, prompted by the recent sudden outbreak of COVID-19, some literature reports on antiviral potential of microalgae polysaccharides among the commercial species are underlined. The overall results of this analysis seem not encouraging about flourishing of new detailed knowledge of fine structural features of these polysaccharides. The situation is reflecting the historical one observed for the launch of polysaccharides in biotechnology since 1950s. Intensive studies on possible exploitation using crude or partially purified and hardly standardized biomass preexisted to more demanding applications with standardized preparations with possible applications in more demanding fields. Only an interdisciplinary effort can lead soon to research for new chemical knowledge on fine structural details that are necessary to increase possible extensions of applications of pure material. © Springer Nature Switzerland AG 2022.

Naphtho[2,1-b]furan derived triazole-pyrimidines as highly potential InhA and Cytochrome c peroxidase inhibitors: Synthesis, DFT calculations, drug-likeness profile, molecular docking and dynamic studies

Napthofuran and its fused heterocyclic derivatives evaluated with varied biological activity functional groups comprise an important class of compounds for new chemical entities. We here in reporting synthesis of new 3-(4-substituted phenyl)naphtho[1′,2′:4,5]furo[2,3-e][1,2,4]triazolo[4,3-c]pyrimidines 6(a-f). Structures of the newly synthesized compounds were confirmed by making use of spectroscopic techniques like IR, NMR and Mass. The DFT calculations were taken for the selected molecules using B3LYP hybrid functional with a 6–31+G (d, p) all-electron basis set using the Gaussian 09 package. The bioactivity predictions were evaluated for the synthesized compounds. The In vitro biological activities were reported for the all compounds 6(a-f). The compound 6a showed high activity of anti-TB and antioxidant activity with at MIC 1.6 μg/ml and at percentage of inhibition (72.54±0.21) at 10μg/ml respectively. The compound 6f (73.21±0.11) showed antioxidant activity better than standard drug BHA (71.32±0.13) at 10 μg/ml. Furthermore, the docking studies for the newly synthesized molecules were carried out by Auto dock software with proteins InhA (4TZK),Cytochrome c peroxidase (2 × 08) and protease (Mpro) of SARS-CoV-2 Omicron (PDB ID: 7TOB). All the compounds showed a strong binding affinity for the docked proteins. The outcome of docking results showed that compound 6ahad excellent binding energies -10.8, -9.4, and -9.0 kcal/mol with 4TZK, 2 × 08, and 7TOB respectively. Lastly, the protein stability, fluctuations of APO-Protein, protein-ligand complexes were investigated through Molecular Dynamics (MD) simulations studies using Desmond Maestro 11.3 and potential lead molecules were identified. © 2023

Natural antimicrobials: An introduction

From historical point of view, nature has always been a rich source of materials, and medicines also came from this vast and immeasurable resource. Ethnologically-based information still has great potential for future explanations of bioactivities of such medicines. Although epidemiological measures (vaccinations) and antimicrobial treatments curb infectious diseases, there is still an urgent need for well-defined molecules from nature. With the decline of de novo synthesis of new chemical entities, the main focus of nature-derived molecule research among the group of antimicrobials is clear definition of antimicrobial spectrum of activities, mechanism of action, stability, mutagenicity and genotoxicity. The possible road is also in silico studies of antimicrobial activities of natural molecules from natural products databases. Cleary displayed preclinical studies may lead to the in vivo studies which can prove the indication of such natural molecules. The main obstacles such as low bioavailability, short half-life and low PK/PD values will be a great challenge for future research. Considering the emerging new diseases, such as SARS-CoV-2 nowadays, and rising scientific awareness about testing known natural molecules, the area of natural antimicrobials is fast, prominent and still encouraging. © The Author(s), under exclusive license to Springer Nature Switzerland AG 2022. All rights reserved.

Potentials for health and therapeutic benefits of garlic essential oils: Recent findings and future prospects

Garlic (Allium sativum) has been known for its potent medicinal activities and its interesting culinary role since ancient times. With over 200 phytochemicals and flavoring compounds elucidated and many others yet to, garlic promises to improve human health and vitality. Just like other phytochemical classes, essential oils for garlic have been reported to show interesting medical activities delving across diverse antimicrobial, cardio-protective, anti-cancer, anti-Alzheimer, anti-diabetic, and immunomodulatory activities. Garlic essential oils contain mainly volatile and non-volatile allyl-sulphur-based compounds, which are a product of the stream decomposition of Allicin (a major component of garlic extract). Although a lot of work has been done on Allicin, there is little substantive work on the bio-availability and toxicities of its essential oil. This study, however, reviewed the methods that in recent times have been used to extract essential oils from garlic, recent studies on composition and therapeutic activities of Garlic essential oils, and a predictive overview of their bioavailability and toxicity. Finally, recommendations for future studies and other interesting prospects of garlic were also highlighted.Copyright © 2022

Quantitative structure analysis of some molecules in drugs used in the treatment of COVID-19 with topological indices

COVID-19 is a disease caused by the new coronavirus, which has been spreading rapidly all over the world. There is no exact drug yet for the treatment of COVID-19 disease, and its treatment is tried to be provided with existing drugs. However, new drug research is being carried out to treat this disease. Topological indices are numerical descriptors based on the molecular graph of the molecular structure. Topological indices are used in modeling to predict the physicochemical properties and biological activities of molecules in the quantitative structure-property relationship (QSPR), quantitative structure-activity relationship (QSAR) studies. In this study, remdesivir, chloroquine, hydroxychloroquine, theaflavin, thalidomide, arbidol, lopinavir, ritonavir drugs used in the treatment of COVID-19 patients are studied. The QSPR model is designed using some degree-based indices, Mostar-type indices, and distance-based topological indices to predict the various physicochemical properties of these drugs. The relationship analyses between the physicochemical properties and the topological indices in the QSPR model are done by using the curvilinear regression method.

On entropy measures of polycyclic hydroxychloroquine used for novel coronavirus (COVID-19) treatment

The molecular structure of hydroxychloroquine (HCQ) used in the treatment of malaria is recently suggested for emergency used in COVID-19. The chemical compound of HCQ is produced by chemical alteration of ethylene oxide from human products, such as waxy maize starch. The molecular graph is a graph comprising of atoms called vertices and the chemical bond between molecules is called edges. A topological index is a numerical representation of a chemical structure which correlates certain physico-chemical characteristics of underlying chemical compounds besides its numerical representation. To distinguish the creation of entropy-based measures from the structure of chemical graphs, several graph properties have been utilized. For computing the structural information of chemical graphs, the graph entropies have become the information-theoretic quantities. The graph entropy measure has attracted the research community due to its potential application in discrete mathematics, biology, and chemistry. In this paper, our contribution is to explore graph entropies for molecular structure of HCQ based on novel information function, which is the number of different degree vertices along with the number of edges between various degree vertices. More precisely, we have explored the degree-based topological characteristics of hydroxyethyl starch conjugated with hydroxychloroquine (HCQ-HEC). Also, we computed entropies of this structure by making a relation of degree-based topological indices with the help of information function. Moreover, we presented the numerical and graphical comparison of the computed results.

Recent Developments in Polyphenol Applications on Human Health: A Review with Current Knowledge.

Polyphenol has been used in treatment for some health disorders due to their diverse health promoting properties. These compounds can reduce the impacts of oxidation on the human body, prevent the organs and cell structure against deterioration and protect their functional integrity. The health promoting abilities are attributed to their high bioactivity imparting them high antioxidative, antihypertensive, immunomodulatory, antimicrobial, and antiviral activity, as well as anticancer properties. The application of polyphenols such as flavonoids, catechin, tannins, and phenolic acids in the food industry as bio-preservative substances for foods and beverages can exert a superb activity on the inhibition of oxidative stress via different types of mechanisms. In this review, the detailed classification of polyphenolic compunds and their important bioactivity with special focus on human health are addressed. Additionally, their ability to inhibit SARS-CoV-2 could be used as alternative therapy to treat COVID patients. Inclusions of polyphenolic compounds in various foods have demonstrated their ability to extend shelf life and they positive impacts on human health (antioxidative, antihypertensive, immunomodulatory, antimicrobial, anticancer). Additionally, their ability to inhibit the SARS-CoV-2 virus has been reported. Considering their natural occurrence and GRAS status they are highly recommended in food.

Screening of Asian Natural Materials to Promote beta-Endorphin Synthesis

Since the recent coronavirus disease 2019 pandemic and the lifestyle changes it necessitated, the demand for mental health treatment has skyrocketed, with long wait lists for both psychological and psychiatric care. Over-the-counter supplements and home remedies are increasingly sought. In this study, we screened natural materials and blended supplements from Asia that may improve the mood and mental health of humans by testing cell viability and expression of the proopiomelanocortin gene as a marker of beta-endorphin production in rat hypothalamus neuron cells. Among 23 tested samples, 3 samples produced significantly higher cell viability in R-HTH-507 cells than the control treatment. In a real-time-polymerase chain reaction (RT-PCR) experiment, 7 samples showed significant beta-endorphin synthesis activity. This is the first report that the Asian natural materials Areca catechu, Moringa oleifera, Lignosis rhinocerus, and Aegle marmelos promote beta-endorphin synthesis;further investigation will identify the active ingredients in the blended samples. These results suggested that these Asian natural materials have great potential to expand the range of treatments for mental health. Copyright © The Author(s) 2023.

COVID-19 Drug Discovery and Comparison Between Generative and Predictive Approach

The spread of the SARS-Cov-2 virus in the human race has caused 6.56M deaths worldwide as of Oct 2022 and has brought the economy to a standstill. It has also introduced several challenges worldwide. So, the need of finding a drug that would be able to dilute the symptoms of COVID-19 in the patients. The current methods for drug discovery via conventional methods are a tedious and time-consuming process. So here, the deep learning algorithms come to our rescue. Scientists and Doctors are diligently studying and analyzing the genome sequence of the virus and trying to understand the interaction between the coronavirus protease and a covalent inhibitor. Taking advantage of one such research work published by Shanghai Tech University, the research attempts in making research which is based on an approach to inhibit the protease of SARS-Cov-2(Or any virus) by a covalent inhibitor(also called Ligand). The research was done for some similar viruses to SARS-Cov-2, like SARS, MERS, and HIV. Protein target GI73745819 - SARS Protease, Protein target GI75593047 - HIV pol polyprotein, NS3 - Hep3 protease, and 3CL-Pro - Mers Protease. Bioactivities measured in these papers by medicinal chemists and biochemists are tracked by The National Center for Biotechnology Information (NCBI) which can be accessed by everyone. The goal of this research is to make efforts toward proposing a potentially highly active molecule against a target protein of the 2019 Novel Coronavirus. This research features training of the model in such a way that it predicts the binding power of the drug toward COVID-19 protease. Then compared and reported the inhibition score of ligand and protease to find out one of the best inhibitors. © 2022 IEEE.

DFT calculations, molecular docking, in vitro antimicrobial and antidiabetic studies of green synthesized Schiff bases: as Covid-19 inhibitor.

In this investigation, we synthesized Schiff bases 2-(2-methoxyphenoxy)-N-(4-methylbenzylidene)ethanamine, N-(4-methoxybenzylidene)-2-(2-methoxyphenoxy)ethanamine and 2-(2-methoxyphenoxy)-N-(4-nitrobenzylidene)ethanamine from 2-(2-methoxyphenoxy)ethanamine and various aromatic aldehydes by the environmentally friendly sonication method. The B3LYP method with a 6-311++G (d, p) basis set was used in the DFT calculation to obtain the optimized structure of the Schiff base MPEA-NIT. The compounds were tested in vitro for inhibition of bacterial growth (disc well method) and inhibition of α-amylase (starch-iodine method). The compounds tested showed inhibitory activities. In addition, they were subjected to PASS analysis, drug likeness, and bioactivity score predictions using online software. To confirm the experimental findings, molecular docking analyses of synthesized compounds on α-amylase (PDB ID: 1SMD), tRNA threonylcarbamoyladenosine (PDB ID: 5MVR), glycosyl transferase (PDB ID: 6D9T), and peptididoglycan D,D-transpeptidase (PDB ID: 6HZQ) were performed. The emergence of a new coronavirus epidemic necessitates the development of antiviral medications (SARS-CoV-2). Docking active site interactions were investigated to predict compounds' activity against COVID-19 by binding with the SARS-CoV-2 (PDB ID: 6Y84).Communicated by Ramaswamy H. Sarma.

MOLECULAR DOCKING AND BIOACTIVITY STUDIES OF COVALENT INHIBITORS TARGETING RDRP OF SARS-COV-2

The objective of the study was to examine the compounds which inhibit the enzyme RNA-Dependent RNA-Polymerase (RdRp) of SARS-CoV-2. In this study, we collected 120 similar compounds of Remdesivir, Favipiravir, Novobiocin, and Cortisone inhibitors from PubChem and docked them within the RdRp enzyme using Patchdock/ Firedock server. Seven compounds were screened based on binding affinity and binding mode analysis and further studied the covalent and hydrogen interaction networks using Ligplot+ software. Moreover, the pharmacore properties and bioactivity of the compounds were analyzed with molinspiration cheminformatics software. In this study, we identified the compounds 56832851, 134443512, and 5745 have more binding affinity and mostly covalent/H-bonding interactions occurred with side chain residues Asp161 (B)-Trp187 (B)-Thr367 (A)-Arg377 (A)-Asn387 (A)-Glu588 (A) of RdRp. Furthermore, these three compounds showed up drug-likeness and biologically active, though further in-vitro investigations are needed. © 2022, Rasayan Journal of Chemistry, c/o Dr. Pratima Sharma. All rights reserved.

Bioactivity classification of SARS-CoV-2 Proteinase using Machine Learning Approaches

Machine learning has seen a considerable increase in performance and interest in scientific research and industrial applications over the previous decade. The success of most current state-of-the-art methods can be linked to recent deep learning advancements. Deep learning has been demonstrated to outperform not only standard machine learning but also highly specialized tools designed by domain specialists when applied to many scientific fields involving the processing of non-tabular data, such as pictures or text. This article will cover ML-based research on SARS-Co V-2 Proteinase Biological Activity classification, with an emphasis on the most recent successes and research trends. SARS-CoV-2 (Severe Acute Respiratory Syndrome Coronavirus 2) produced a global pandemic of coronavirus illness (COVID-19), which prompted a rush to find treatment options. Despite the attempts, no vaccine or medicine for therapy has been approved. In this paper, we mentioned some previous articles that have resulted in successful bioactivity prediction. The discussion of the machine having to learn technology that has been used for bioactivity prediction in general and has the potential to lead the way for successful working with complex molecules in the future is also a focus of this review. The study finishes with a brief viewpoint on contemporary machine learning research advances, including student engagement and semi-supervised learning, which offer considerable potential for increasing bioactive discovery. © 2022 IEEE.

Pharmacophore-Based Virtual Screening of Potential SARS-CoV-2 Main Protease Inhibitors from Library of Natural Products

Background: The SARS-CoV-2 main protease (Mpro) is an attractive target for drug discovery. Method(s): A pharmacophore model was built using the three-dimensional (3D) pharmacophore generation algorithm HypoGen in Discovery Studio 2019. The best pharmacophore model was selected for validation using a test set of 24 compounds and was used as a 3D query for further screening of an in-house database of natural compounds. Lipinski's rule of five was used to assess the drug-like properties of the hit compounds. The filtered compounds were then subjected to bioactivity evaluations. The active compounds were docked into the active site of the SARS-CoV-2 Mpro crystal structure (PDB ID: 7D1M). Result(s): A suitable 3D pharmacophore model, Hypo1, was found to be the best model, consisting of four features (one hydrophobic feature, one hydrogen bond donor, and two hydrogen bond acceptors). Pharmacophore-based virtual screening with Hypo1 as the query to search an in-house database of 34 439 natural compounds resulted in 1502 hits. Among these, 255 compounds satisfied Lipinski's rule of five. The highest ranking 10 compounds were selected for further experimental testing, and one hit (W-7) illustrated inhibitory activity against SARS-CoV-2 Mpro with an IC50 value of 75 muM. Docking studies revealed that this hit compound retained the necessary interactions within the active site of SARS-CoV-2 Mpro. Conclusion The identified lead natural compound could provide a scaffold for the further development of SARS-CoV-2 Mpro inhibitors. Copyright © The Author(s) 2022.

Generative Recurrent Network For Design SARS-CoV-2 Main Protease Inhibitor

Deep learning was adopted in de novo drug design for its generative ability in generating novel molecules, by training on a small set of molecules with known biological activity towards the target, the model will be finetuned to generate similar molecules. We proposed a method similar to the process found in evolution algorithms from creating, evaluating, and selecting from a population for fine-tuning the generative model without the need for molecules with known biological activity and applied it to the SARS-CoV-2, the proposed method decreases the time required to search for SARS-CoV-2 main protease inhibitors by developing a predictive model for predicting the affinity score of the molecules which decreases the time needed for docking to a fraction of the original time, we achieved 97.6 % accuracy in predicting the affinity score of molecules thus speeding up the search for existing molecules and the fine-tuning of the generative model to design protease inhibitors for SARS-CoV-2. © 2022 University of Split, FESB.

Antiviral potential of frequently used plants in herbal formulations as immunity enhancers against SARS-CoV-2

A severe acute respiratory syndrome (SARS) is an extraordinary type of communicable infection that is caused by SARS-coronavirus. Since last two years, the entire world is fighting with this highly infectious disease and researchers are devoting all their labours to develop vaccines and few vaccines with remarkable efficacies have been developed. However, the great rate of mutations in SARS-CoV-2 annoying everyone. Though, the scientific communities are doing their best towards neutralizing the impact of infection yet the best way to combat this virus and future similar infections is to boost our immune system in a natural way. In this review, the prospective of widespread and easily available plants have been discussed as immunity enhancers to combat COVID-19 and other viruses.

Metabolites and Their Bioactivities from the Genus Cordyceps.

The Cordyceps genus is a group of ascomycete parasitic fungi, and all known species of this genus are endoparasites; they mainly feed on insects or arthropods and a few feed on other fungi. Fungi of this genus have evolved highly specific and complex mechanisms to escape their host's immune system and coordinate their life cycle coefficients with those of their hosts for survival and reproduction; this mechanism has led to the production of distinctive metabolites in response to the host's defenses. Herein, we review approximately 131 metabolites discovered in the genus Cordyceps (including mycelium, fruiting bodies and fungal complexes) in the past 15 years, which can be used as an important source for new drug research and development. We summarize chemical structures, bioactivity and the potential application of these natural metabolites. We have excluded some reports that originally belonged to Cordyceps, but whose taxonomic attribution is no longer the Cordyceps genus. This can and will serve as a resource for drug discovery.

Deterrent to COVID-19 infection - adopting a Srilankan university research study

This study provides a simple, widely available deterrence medication to minimize COVID-19 infection using by tea and coffee infusions. By mixing white with an equal amount of water, add a small amount of tea/coffee infusion. Dull brownish albumen-tannin complex, a soft precipitate is formed and sinks to the bottom. The infusion should reach the furthest points in the respiratory tract so that a maximum number of viral particles are trapped. It is necessary to hold the infusion rolling about for a little while, 20 seconds in the mouth before swallowing. Gargling with the infusion is better. Tannins in tea or coffee infusions will form complexes with the 4-5 types of viral surface proteins [spikes], rendering them ineffective. Protein-tannin astringent complexation is a fundamental chemical reaction and is bound to act, unlike specific antimetabolites or enzyme-mediated actions of antibiotics. In fact, tannins react to some extent with the cell lining of the mucous membranes of the mouth and stomach. Tannins also chelate iron [Fe] and other metal ions required for many of the metabolic reactions of micro-organisms [viruses?], depriving them of these nutrients and further retarding their propagation. Two gargles per day, 12 hours apart, are recommended to disable the virus and eventually kill it. The procedure disables free viruses before tissue invasion. Therefore, the earlier the gargle commences, the better. Suspected contacts should preferably have three daily eight-hourly gargles. Astringent activity is an added activity of tea and coffee, demonstrated in this study [using E. coli and Salmonella] to that of immune boosting action generally spoken about.

New evidence for aerosol transmission of SARS-CoV-2

Since the outbreak of COVID-19, the opinion that the aerosol plays a key role in the transmission of SARS-CoV-2 has been controversial. The COVID-19 pandemic has continued interpersonal transmission for more than two years, especially after the emergence of Delta and Omicron variants, making the situation of COVID-19 pandemic more severe. The transmission of SARS-COV-2 variants was significantly accelerated and the time of transmission between generations was significantly shortened. Therefore, it has been questioned to attribute the close-range infection to droplet transmission. The point that the aerosol can also has a close-range transmission and may play a dominant role is neglected under the influence of traditional transmission mode of respiratory infectious diseases. A large number of studies have shown that normal breath, talk and cough could release a large number of respiratory aerosol particles, and the virus particles were mainly tiny particles(=5.0 micro m). The biological activity and infectivity of the droplet nuclei have been questioned in the studies on their physicochemical properties. Animal models of ferrets and hamsters showed that SARS-COV-2 could transmit via aerosol. Therefore, the new evidence for the aerosol transmission of SARS-COV-2 was reviewed in the article so as to provide latest evidence-based evidence for prevention and control of COVID-19.

Structural, spectral, bioactivity, antioxidant and molecular docking (with SARS-CoV-2) analyses on a new synthesized thiosemicarbazide derivative

Spectroscopic characterization of the N'-(4-nitrophenylcarbonothioyl) nicotinohydrazide molecule has been studied using both experimental (X-ray diffraction and IR spectroscopy) and quantum mechanical methods. The tautomeric energetic analysis, structural optimization parameters (bond lengths and angles), vibrational wave numbers, UV-Vis. parameters, the highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) analyses and Molecular Electrostatic Potential (MEP) surface have been calculated by using DFT/B3LYP method with 6-311++G(2d,2p) level of theory to compare with the experimental results. The radical scavenging activity of the synthesized new compound has been evaluated using three different test methods. For this purpose, 2,2'-azino-bis-(3- ethylbenzothiazoline-6-sulfonate) (ABTS), N,N-dimethyl-p-phenylenediamine (DMPD) and 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity tests has been done. The pharmacokinetic, physicochemical, and toxicity properties have been defined by using drug-likeness and in silico ADMET studies. The interaction characterization with SARS-CoV-2 main protease (Mpro) of the title compound has been investigated via the help of a molecular docking study.