Secondary Metabolite and Antioxidant Activity of Endophytic Fungi Isolated from Syzygium aqueum Leaves Stalk

Medicinal plants are a promising host for endophytic fungi to produce secondary metabolites relevant for food and health. In this study, we evaluate antioxidant activity to determine the species of endophytic fungi isolated from Syzygium aqueum. Endophytic fungi were isolated from leaf stalks through surface sterilization. The fungi’s isolate was identified with morphology and molecular analysis (ITS-rDNA). The pure fungi strain was cultivated on PDB media for 4 weeks, and metabolites were extracted using ethyl acetate. The crude extract of endophytic fungi was examined for its antioxidant activity using 2,2-diphenyl-1-picrylhydrazyl (DPPH). The pure compound was isolated using the chromatography method, and its structure was determined using spectroscopy analysis involving NMR 1D and 2D. In total, four obtained endophytic fungi were isolated from leaf stalks. The fungi with good antioxidant activity (IC50 59.2 µg/mL) were identified as Beltrania rhombica. The characteristics of the pure compound are white-yellowish powder with IC50 44.2 µg/mL. Based on spectroscopy analysis, the pure compound was identified as 3-(hydroxyl(3,4,5-trihydroxylphenyl)methyl)-3,4-dihydro-2H-pyran-4,5,6-triol.

Aspergillus flavus originated pure compound as a potential antibacterial

Problem Background Penicillin was the first and most famous fungal secondary metabolite used as broad spectrum antibiotic that revolutionarised pharmaceutical research and also saved millions of lives. The over optimistic belief in 1967 that sufficient antibiotics had been discovered to defeat infectious diseases was quickly crashed with the appearance of multidrug resistant (MDR) bacteria in 1990s. This has posed a serious threat to mankind. Although scientists are making efforts to synthesize and discover new antibiotics there are not enough new drugs in pharmaceutical pipeline to beat the pace at which MDR bacteria are emerging. In view of this there is an urgent and serious medical need for new bioactive compounds to be discovered to treat infections caused by MDR pathogens. The present study is aimed to investigate the antibacterial potential of Aspergillus flavus originated compounds that may act as drug leads to treat future infections. Methodology Among the 6 isolated fungal strains from the rhizosphere of Mentha piperetta, one was processed for isolation of secondary metabolites on the basis of preliminary antibacterial testing. Observation of morphological and microscopic features helped in identification of the fungal strain as Aspergillus flavus. Potato Dextrose Agar (PDA) medium was used for fungal growth while Czapec Yeast Broth (CYB) medium was used for production of fungal metabolites. Column chromatography technique was utilized for purification of compound from crude fungal extract and the mass of the compound was determined using Liquid Chromatography Mass Spectrometry (LCMS) method. Structure elucidation of the pure compound was performed using 500 Varian Nuclear Magnetic Resonance (NMR) machine. Docking was performed using Glide SP algorithm. Agar well diffusion method was used to determine the invitro antibacterial potential of the compound against two MDR bacterial strains i.e. Staphylococcus aureus and Proteus vulgaris. For this a total of 4 dose concentrations i.e. (100, 250, 500, 1000 μg mL− 1) of the compound were prepared and applied to bacterial strains on Mueller Hinton agar using tetracycline as control. Results The chemical name of the purified compound from A. flavus was determined as (2E)-3-[(3S, 4R)-8-hydroxy-3, 4-dimethyl-1-oxo-3, 4-dihydro-1H-2- benzopyran-7-yl] prop-2-enoic acid with the formula C14H14O5 and exact mass of 262.08. The in-Silico analysis showed that this compound has the potential to inhibit the binding pocket of S. aureus TyrRS (1JII) with docking score of − 8.67 Kcal mole− 1. The results obtained from invitro experiments were encouraging as at 1000 μg mL− 1 the compound showed 58.8% inhibition against S. aureus and 28% inhibition against P. vulgaris. Conclusions The pure compound with formula C14H14O5 and exact mass of 262 exhibited antibacterial potential both insilico and invitro against both Gram negative and Gram positive bacteria. The compound was more active against S. aureus in comparison to P. vulgaris. From the obtained results it is concluded that this compound can be used as potent antibacterial candidate but further studies will be needed prior to its use as antibiotic.

Pyranoanthocyanins Interfering with the Quorum Sensing of Pseudomonas aeruginosa and Staphylococcus aureus

Bacterial quorum sensing (QS) is a cell-cell communication system that regulates several bacterial mechanisms, including the production of virulence factors and biofilm formation. Thus, targeting microbial QS is seen as a plausible alternative strategy to antibiotics, with potentiality to combat multidrug-resistant pathogens. Many phytochemicals with QS interference activity are currently being explored. Herein, an extract and a compound of bioinspired origin were tested for their ability to inhibit biofilm formation and interfere with the expression of QS-related genes in Pseudomonas aeruginosa and Staphylococcus aureus. The extract, a carboxypyranoanthocyanins red wine extract (carboxypyrano-ant extract), and the pure compound, carboxypyranocyanidin-3-O-glucoside (carboxypyCy-3-glc), did not cause a visible effect on the biofilm formation of the P. aeruginosa biofilms; however, both significantly affected the formation of biofilms by the S. aureus strains, as attested by the crystal violet assay and fluorescence microscopy. Both the extract and the pure compound significantly interfered with the expression of several QS-related genes in the P. aeruginosa and S. aureus biofilms, as per reverse transcription-quantitative polymerase chain reaction (RT-qPCR) results. Indeed, it was possible to conclude that these molecules interfere with QS at distinct stages and in a strain-specific manner. An extract with anti-QS properties could be advantageous because it is easily obtained and could have broad, antimicrobial therapeutic applications if included in topical formulations.

Antimycobacterial cycloartane derivatives from the roots of Trichilia welwistchii C. DC (Meliaceae)

Chemical investigation of the roots of Trichilia welwitschii yielded a cycloartane type terpenoid 28,29-bis-norcycloart-24-en-3β,4α,6α-triol (1), isolated as pure compound for the first time, three coumarins and three sterols. New cycloartane derivatives (1a) and (1b+1c) were obtained by hemi-synthetic reaction of compound 1. The structures of 1a–c were established by spectroscopic methods including 1D and 2D-NMR analysis, HR-EIMS, chemical transformations and by comparison of these data with those of related compounds. Evaluated for their antimycobacterial potential, compound 1 and 1b+1c were determined to show significant activities against Mycobacterium tuberculosis MIC values of 6.25 μg mL−1 while compound 1a displayed weak activity showing MIC > 100 μg mL−1. Compounds 2–4 displayed moderate activity with MIC values range from 12.5 to 50 μg mL−1.

Isolation, Characterization and Antibacterial Activity of ECDY Steroid from Roots of Polycarpaea corymbosa LAM

A new phytoecdysteroid (2- deoxy 20 hydroxy 22 cinnamoyl ecdysone 3, 25 diacetate) was isolated from the roots of Polycarpaea corymbosa Lam (family: caryophyllaceae).The powdered roots were extracted with petroleum ether ( 60-80? C), benzene, ethyl acetate and ethyl alcohol in soxhlet apparatus by simultaneous extraction. The highest yield of benzene extract was chosen for the isolation of ecdysteroid. The white solid pure compound was isolated and tested by TLC and respond positively for Liebermann - burchard reaction. Their structure has been established by UV, IR, 1H, 13C-NMR DEPT -90, DEPT -135 and EI- MS experiments. All the extracts and isolated compound were screened for anti-bacterial activity against B.subtilis, P.vulgaris, E.coli, P.aeruginosa by Kirbybauer method.

In Vitro and In Vivo Anti-Inflammatory Activity of Tetrastigma Sulcatum Leaf Extract, Pure Compound and Its Derivatives

The severity and perseverance of the inflammation have been demonstrated in many health conditions. The limitations of existing medications, propose the need for newer alternative anti-inflammatory medications. In our earlier studies, we demonstrated the topical anti-inflammatory potential of crude ethanolic extract of Tetrastigma sulcatum leaves and its fractions. In the present study, we further explored anti-inflammatory activity of T. sulcatum extract, fractions, pure compound and its derivatives using in vitro and in vivo bioassay techniques. We attempted to isolate a pure compound from leaf extract and was identified as Friedelan-3β-ol (CI) and its derivatives Friedelinol acetate (C II) and Friedelinol methyl ether (C III) were synthesized. Treatment with crude extract and its fractions demonstrated a significant reduction in the mRNA expression levels of pro-inflammatory cytokines (IL-1β, IL-6, TNF-α) and nitric oxide (NO) production in LPS-stimulated inflammation in RAW 264.7 cells. Likewise, compounds CI, CII and CIII showed a similar pattern of significant inhibition of proinflammatory cytokines and NO production. In vivo study in Carrageenan induced paw-inflammatory mice model demonstrated reduced paw oedema and proinflammatory cytokines levels in a dose-dependent manner upon treatment of extract, its fractions, pure compound (CI), and their derivatives (CII and CIII.). The docking study showed all the compounds (CI, CII and CIII) share common residues with Dexamethasone. TNF- α exhibited the most interacting residues with the compounds. The present study confirmed the T. sulcatum ’s anti-inflammatory activity, suggesting Friedelan-3β-ol as an active component in a crude extract.

ANTIVIRAL ACTIVITY OF EXTRACT AND PURIFIED COMPOUND FROM RED MACROALGAE ASPARAGOPSIS TAXIFORMIS AGAINST H5N1 VIRUS

Aim and objective: The discovery and development of new natural antiviral compounds which exhibit various antiviral activities are required. The aim of this investigation is to assess the potential use of the red seaweed Asparagopsis taxiformis as a new source of anti H5N1 agent. Methods: The seaweed was collected from Marsa Matrouh, Mediterranean Sea, Egypt during spring season, the effects of successive extracts and the pure compounds from the investigated alga on H5N1 virus were performed using plaque reduction assay. In addition, the mechanism of action of promising extract on the virus adsorption and replication was determined. Chromatographic and spectroscopic analyses were used for the identification of chemical structure of active compound(s) isolated from the studied seaweed. Results: The obtained results showed that petroleum ether and water algal extracts exhibited high antiviral activity (>99.9%) and the mode of action of extracts was not correlated with virus replication but with its adsorption process.The isolated pure compound was identified as 6-methyl-Δ22-stigmasterol-2, 3 di acetate and its antiviral activity (for H5N1)was tested. Pure compound showed antiviral activity reached 56% at 100 µg/ml. Conclusion: The obtained results suggests that crude extracts and isolated active compound from A. taxiformis has the capacity to protect people against pandemic H5N1preventing virus adsorption to the human host cells. Recommendation for testing the extracts and pure compounds from the studied seaweed as potential inhibitor of COVID-19. Peer Review History: Received 16 March 2021; Revised 29 March; Accepted 21 April, Available online 15 May 2021 UJPR follows the most transparent and toughest ‘Advanced OPEN peer review’ system. The identity of the authors and, reviewers will be known to each other. This transparent process will help to eradicate any possible malicious/purposeful interference by any person (publishing staff, reviewer, editor, author, etc) during peer review. As a result of this unique system, all reviewers will get their due recognition and respect, once their names are published in the papers. We expect that, by publishing peer review reports with published papers, will be helpful to many authors for drafting their article according to the specifications. Auhors will remove any error of their article and they will improve their article(s) according to the previous reports displayed with published article(s). The main purpose of it is ‘to improve the quality of a candidate manuscript’. Our reviewers check the ‘strength and weakness of a manuscript honestly’. There will increase in the perfection, and transparency. Received file: Reviewer's Comments: Average Peer review marks at initial stage: 6.5/10 Average Peer review marks at publication stage: 8.0/10 Reviewer(s) detail: Prof. Dr. Hassan A.H. Al-Shamahy, Sana'a University, Yemen, [email protected] Dr. Wadhah Hassan Ali Edrees, Hajja University, Yemen, [email protected] Similar Articles: ANTIDIABETIC AND ANTIHYPERLIPIDEMIC ACTIVITY OF DRACAENA CINNABARI BALF. RESIN ETHANOLIC EXTRACT OF SOQATRA ISLAND IN EXPERIMENTAL ANIMALS ANTIHYPERGLYCEMIC AND ANTI-OXIDANT POTENTIAL OF ETHANOL EXTRACT OF VITEX THYRSIFLORA LEAVES ON DIABETIC RATS

Effectiveness of isolated compound from Aloe barbadensis Miller and its formulated ointment against bacteria and fungi

Ethnomedicinally, the family Liliaceae is prominent in controlling skin, wound and fungal infections. A carboxylic fatty acid derivative has been isolated from Aloe vera leaves and its structure was elucidated on the basis of NMR and FT-IR analysis. The compound was formulated as ointment with the aid of polymer based delivery agent. The ointment and the uncontaminated fatty acid have been scrutinized aimed at their anti-infectious potential. Individually, the pure compound and the formulated ointment exhibited growth inhibitory activity against Pseudomonas aeruginosa, Escherichia coli, Staphylococcus aureus, Klebsiella pneumoniae, Candida albicans and Talaromyces flavus. Minimum inhibitory concentration (MIC) values were found to be appreciably low, ranging between 0.30 and 2.50 mg/ml. The formulated ointment displayed highly significant inhibitory activities against all six pathogens compared to the unformulated compound. The MIC values of the ointment ranged between 0.08 and 1.25 mg/g. The in vitro antibiotic activity studies discovered that, both the pure compound and the formulated ointment showed potency against the selected multi-resistant microorganisms tested in the current work. These findings suggest that the isolated carboxylic acid derivative may be beneficial in the discovery of antibiotics highly potent against drug-resistant pathogens. Furthermore, it may add to the improvement of preservatives in the food industry. Lastly, it could be considered as new source of natural antibiotics in the pharmaceutical industry.

Synthesis of urease inhibitory 2, 4-bis (4-cyanobenzyl)glycoluril using sandmeyer reaction and density functional theory investigation

Aims: The aim of present research was to synthesize glycoluril derivative 2,4-Bis(4-cyanobenzyl)glycoluril through convergent scheme. Background: For this purpose Sandmeyer reaction procedure was employed for the synthesis of said compound. The structure of the pure compound was confirmed by using different spectroscopic techniques such as 1H-NMR, 13C-NMR and (HR-MS) Mass spectrometry. Objective: Convergent synthesis of 2,4-BIS (4-CYANOBENZYL)GLYCOLURIL USING SANDMEYER REACTION and urease inhibition study. Methods: The structure of the pure compound was confirmed by using different spectroscopic techniques such as 1H-NMR, 13C-NMR and (HR-MS) Mass spectrometry. The electronic properties of newly synthesized compound and thiourea were determined by using density functional theory. Results: Furthermore compound was evaluated against urease enzyme and was found to be potent inhibitors with IC50 value of 11.5 ± 1.50 µM when compared with standard inhibitor thiourea (IC50 = 21.0 ± 1.90 µM). Compound may serve as lead compound for the synthesis of new cyano based bambusuril in future with enhanced biological properties. Conclusion: We have synthesized a new glycoluril derivative 2,4-Bis(4-cyanobenzyl)glycoluril by the sandmeyer reaction. It has obtained in the form of light yellowish powder in good yield (96%). Glycoluril based macrocycles have been used in various fields. Starting from the 2,4-Bis(4-nitrobenzyl)glycoluril (already reported compound) which has undergone reduction (CH3OH,Pt/C) , diazotization (NaNO2/HCl), cyanation (CuCl/KCN) respectively in order to synthesize the desired new glycoluril derivative. The obtained product will be used as a building block for the synthesis of the cyano based bambusuril marcocycle in future. The yield of the obtained product has been monitored by using different amount of cyanating reagent but the best results shown by the use of 4 mmol of CuCl/KCN. KCN with CuCl assisted the conversion of diazo group into cyano group with enhanced yield when used in excess amount. It act as a catalyst. Solubility characteristic of 2,4-Bis(4-cyanobenzyl)glycoluril has determined also in different organic solvents. 1H NMR technique proved to be very helpful for the structure determination of our desired product. Benzylic protons give signals at 7.5 ppm and 7.8 ppm respectively. The downfield peaks confirm about the presence of CN group near the benzylic protons. Methine protons show signal at 5.2 ppm which ensures about the basic skeleton of glycoluril. Ureidyl protons also confirm the synthesis of the heterocyclic 2,4-Bis(4-cyanobenzyl)glycoluril compound. The negative and positive electrostatic potential sites, molecular descriptors, and charge density distribution of frontier molecular orbitals are revealing that 4a with promising sites for electrophilic and nucleophilic attacks would result to enhance the urease inhbition which is in good agreement with the experimental data.

History of penicillin

The history of penicillin was shaped by the contributions of numerous scientists. The ultimate result was the discovery of the mould Penicillium's antibacterial activity and the subsequent development of penicillins, the most widely used antibiotics. Following an accidental discovery of the mould, later identified as Penicillium rubens, as the source of the antibacterial principle (1928) and the production of a pure compound (1942), penicillin became the first naturally derived antibiotic. There is anecdotal evidence of ancient societies using moulds to treat infections and of awareness that various moulds inhibited bacterial growth. However, it is not clear if Penicillium species were the species traditionally used or if the antimicrobial substances produced were penicillin. In 1928, Alexander Fleming was the first to discover the antibacterial substance secreted by the Penicillium mould and concentrate the active substance involved, giving it the name penicillin. His success in treating Harry Lambert's streptococcal meningitis, an infection until then fatal, proved to be a critical moment in the medical use of penicillin. Many later scientists were involved in the stabilisation and mass production of penicillin and in the search for more productive strains of Penicillium. Among the most important were Ernst Chain and Howard Florey, who shared with Fleming the 1945 Nobel Prize in Physiology or Medicine.