In Vitro Antioxidant and In Silico Evaluation of the Anti-ß-Lactamase Potential of the Extracts of Cylindrospermum alatosporum NR125682 and Loriellopsis cavenicola NR117881.

Cyanobacteria in recent times have been touted to be a suitable source for the discovery of novel compounds, including antioxidants and antibiotics, due to their large arsenal of metabolites. This study presents the in vitro antioxidant and in silico evaluation of Cylindrospermum alatosporum NR125682 and Loriellopsis cavenicola NR117881, isolated from freshwater ponds around the campus of the University of Zululand, South Africa. The isolates were confirmed using 16S rRNA. Various crude extracts of the isolated microbes were prepared through sequential extraction using hexane, dichloromethane, and 70% ethanol. The chemical constituents of the crude extracts were elucidated by FTIR and GC-MS spectroscopy. The antioxidant potential of the extracts was determined by the free radical (DPPH, ABTS, •OH, and Fe2+) systems. Molecular docking of the major constituents of the extracts against ß-lactamase was also evaluated. GC-MS analysis indicated the dominating presence of n-alkanes. The extracts exhibited varying degrees of antioxidant activity (scavenging of free radicals; an IC50 range of 8-10 µg/mL was obtained for ABTS). A good binding affinity (-6.6, -6.3 Kcal/mol) of some the organic chemicals (diglycerol tetranitrate, and 2,2-dimethyl-5-(3-methyl-2-oxiranyl)cyclohexanone) was obtained following molecular docking. The evaluated antioxidant activities, coupled with the obtained docking score, potentiates the antimicrobial activity of the extracts.

Isolation and Characterization of Potential Lignin Peroxidase-Producing Bacteria from Compost Samples at Richards Bay (South Africa).

Lignin recalcitrance is a key issue in producing value-added products from lignocellulose biomass. In situ biodegradable lignin-modifying enzymes-producing bacteria are considered a suitable solution to lignin biodegradation problems, but exploitation of ligninolytic bacteria is still limited to date. Hence, this study aimed to isolate and characterize potential lignin peroxidase ligninolytic bacteria from decomposing soil, sawdust, and cow dung at Richard Bay, South Africa. The samples were collected and cultured in the lignin-enriched medium. Pure isolated colonies were characterized through 16S rRNA gene sequencing. The ability of the isolates to grow and utilize aromatic monomers (veratryl and guaiacol alcohol) and decolorize lignin-like dyes (Azure B, Congo Red, Remazol Brilliant Blue R) was evaluated. Of the twenty-six (26) bacteria isolates 10 isolates, including Pseudomonas spp. (88%), Enterobacter spp. (8%), and Escherichia coli (4%) were identified as true lignin peroxidase producers. Pseudomonas aeruginosa (CP031449.2) and E. coli (LR025096.1) exhibited the highest ligninolytic activities. These isolates could potentially be exploited in the industry and wastewater treatment as effective lignin degrading agents.

In vitro antiviral, antioxidant and in vivo antipyretic activity of three South Africa medicinal plants crude extracts / Actividad antiviral, antioxidante y antipirética in vivo de tres extractos crudos de plantas medicinales de Sudáfrica

This study investigated anti-viral, antioxidant activity and anti-pyretic of crude extract from Artemisia afra, Artemisia absinthium and Pittiosporum viridflorum leaves. The crude extracts were prepared by maceration using aqueous, methanol and dichloromethane respectively. Antiviral studies were evaluated with influenza virus using Fluorescence based - Neuraminidase inhibitors. Antioxidant activities determined with DPPH, Nitric oxide, hydroxyl and super oxide anion radicals' Anti-pyretic activities were evaluated using rats with yeast induced pyrexia. Total phenol, flavonoids, and pro-anthocyanin contents of the plants samples were evaluated using standard protocols. The crude extracts exhibited neuraminidase inhibitory activity against the influenza virus at different thresholds. Artemisia absinthiumaqueous extract showed the best activity against A/Sydney/5/97. Whereas Artemisia afra methanol crude extract displayed highest antioxidant potential against the tested antioxidant parameters. All the crude extracts significantly reversed yeast induced pyrexia in rats, similar to paracetamol. Thus, they could serve as natural remedy for respiratory diseases such as Influenza.

Este estudio investigó la actividad antiviral, antioxidante y antipirética del extracto crudo de hojas de Artemisia afra, Artemisia absinthium y Pittiosporum viridflorum. Los extractos crudos se prepararon mediante maceración utilizando metanol acuoso y diclorometano respectivamente. Los estudios antivirales se evaluaron con el virus de la influenza utilizando inhibidores de neuraminidasa basados en fluorescencia. Actividades antioxidantes determinadas con DPPH, radicales aniónicos de óxido nítrico, hidroxilo y superóxido. Las actividades antipiréticas se evaluaron utilizando ratas con pirexia inducida por levaduras. El contenido total de fenol, flavonoides y proantocianina de las muestras de plantas se evaluó utilizando protocolos estándar. Los extractos crudos mostraron actividad inhibidora de neuraminidasa contra el virus de la influenza en diferentes umbrales. El extracto acuoso de Artemisia absinthium mostró la mejor actividad contra A/Sydney/5/97. Mientras que el extracto crudo de Artemisia aframetanol mostró el mayor potencial antioxidante contra los parámetros antioxidantes probados. Todos los extractos crudos revirtieron significativamente la pirexia inducida por levaduras en ratas, similar al paracetamol. Por tanto, podrían servir como remedio natural para enfermedades respiratorias como la Influenza.

In vitro and in vivo antioxidant potentials of the methanolic crude extract from Inula glomerata Oliv. & Hiern (Asteraceae) and Salacia kraussii (Harv) Harv (Celastraceae) / Potenciales antioxidantes in vitro e in vivo del extracto crudo metanólico de Inula glomerata Oliv. & Hiern. (Asteraceae) y Salacia kraussii (Harv) Harv (Celastraceae)

Reactive oxygen species are implicated in multiple pathological conditions including erectile dysfunction. This study evaluated the in vitro and in vivo antioxidant potential of the methanolic extracts of Inula glomerata and Salacia kraussii. The plant materials were pulverized and extracted with methanol. The phytochemical analysis, ability of the crude extracts to scavenge free radicals (ABTS, DPPH, NO.) in vitroas well as the total phenolic and flavonoid contents was investigated. In vivo, antioxidant potentials of the crude extracts (50/250 mg/kg body weight) were determined in an erectile dysfunction rat model. The phytochemical analysis revealed that both plants contain flavonoids, tannins, terpenoids, and alkaloids. The crude extracts at varying degree of efficiency, scavenged ABTS and DPPH radicals. The crude extracts at low concentrations (50 mg/kg b.w) significantly (p<0.05) diminished the level of malondialdehyde, augmented catalase activities and elevated glutathione levels. However, SOD activities were significantly boosted in a dose-dependent manner by the crude extracts. Therefore, I. glomerataand S. kraussiipossess antioxidant properties, hence, can serve as a therapeutic modality in the treatment of oxidative stress-induced erectile dysfunction.

Las especies reactivas de oxígeno están implicadas en múltiples condiciones patológicas, incluyendo la disfunción eréctil. Este estudio evaluó el potencial antioxidante in vitro e in vivo de extractos metanólicos de Inula glomeratay Salacia kraussii. Los materiales vegetales fueron pulverizados y extraídos con metanol. A estos extractos crudos se les llevó a cabo el análisis fitoquímico junto con el contenido total de fenólicos y flavonoides, así como se les investigó la capacidad in vitro para atrapar radicales (ABTS, DPPH, NO.). Los potenciales antioxidantes in vivo de los extractos crudos (50/250 mg/kg de peso corporal) se determinaron en un modelo en ratas con disfunción eréctil. El análisis fitoquímico reveló que ambas plantas contuvieron flavonoides, taninos, terpenoides y alcaloides. Los extractos crudos con un grado variable de eficiencia, atraparon a los radicales ABTS y DPPH. Los extractos crudos a bajas concentraciones (50 mg/kg p.c) significativamente (p<0.05) disminuyeron el nivel de malondialdehído, aumentaron las actividades de catalasa y elevaron los niveles de glutatión. Sin embargo, las actividades de SOD por los extractos crudos fueron significativamente dosis-dependientes. Así, los extractos de I. glomeratay S. kraussii mostraron propiedades antioxidantes, y por lo tanto, podrían servir como una alternativa terapéutica en el tratamiento de disfunción eréctil inducida por estrés oxidativo.

Synthesis of substituted N-(2'-nitrophenyl)pyrrolidine-2-carboxamides towards the design of proline-rich antimicrobial peptide mimics to eliminate bacterial resistance to antibiotics.

The treatment of diseases is under threat due to the increasing resistance of disease-causing bacteria to antibiotics. Likewise, free radical-induced oxidative stress has been implicated in several human disease conditions, such as cancer, stroke and diabetes. In the search for amino acid analogues with antibacterial and antioxidant properties as possible mimics of antimicrobial peptides, substituted N-(2'-nitrophenyl)pyrrolidine-2-carboxamides 4a-4k and N-(2'-nitrophenyl)piperidine-2-carboxamides 4l-4n have been synthesized via a two-step, one-pot amidation of the corresponding acids, using thionyl chloride with different amines in dichloromethane. The carboxamides were characterized by infrared and nuclear magnetic resonance spectroscopy, mass spectrometry and elemental analysis. Carboxamides 4a-4n were assayed against five Gram-positive and five Gram-negative bacterial strains using the broth micro-dilution procedure and compared to standard antibiotic drugs (streptomycin and nalidixic acid). 4b showed the highest antibacterial activity with a minimum inhibitory concentration (MIC) value of 15.6 µg/mL against Staphylococcus aureus. Pertinently, 4b and 4k are promising candidates for narrow-spectrum (Gram-positive) and broad-spectrum antibiotics, respectively. The antioxidant properties of the carboxamides were also evaluated using the 1,1-diphenyl-2-picryl hydrazyl (DPPH) radical and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) radical cation. 4a and 4k recorded the lowest IC50 values of 1.22 × 10-3 mg/mL (with DPPH) and 1.45 × 10-4 mg/mL (with ABTS), respectively. Notably, 4k recorded about 2.5 times better antioxidant capacity than the positive controls - ascorbic acid and butylated hydroxyanisole. These results bode well for N-aryl carboxamides as good mimics and substitutes for antimicrobial peptides towards mitigating bacterial resistance to antibiotics as well as ameliorating oxidative stress-related diseases.

A Lanosteryl Triterpene from Protorhus longifolia Improves Glucose Tolerance and Pancreatic Beta Cell Ultrastructure in Type 2 Diabetic Rats.

Type 2 diabetes remains one of the leading causes of death worldwide. Persistent hyperglycemia within a diabetic state is implicated in the generation of oxidative stress and aggravated inflammation that is responsible for accelerated modification of pancreatic beta cell structure. Here we investigated whether a lanosteryl triterpene, methyl-3ß-hydroxylanosta-9,24-dien-21-oate (RA-3), isolated from Protorhus longifolia can improve glucose tolerance and pancreatic beta cell ultrastructure by reducing oxidative stress and inflammation in high fat diet and streptozotocin-induced type 2 diabetes in rats. In addition to impaired glucose tolerance, the untreated diabetic rats showed increased fasting plasma glucose and C-peptide levels. These untreated diabetic rats further demonstrated raised cholesterol, interleukin-6 (IL-6), and lipid peroxidation levels as well as a destroyed beta cell ultrastructure. Treatment with RA-3 was as effective as metformin in improving glucose tolerance and antioxidant effect in the diabetic rats. Interestingly, RA-3 displayed a slightly more enhanced effect than metformin in reducing elevated IL-6 levels and in improving beta cell ultrastructure. Although the involved molecular mechanisms remain to be established, RA-3 demonstrates a strong potential to improve pancreatic beta cell ultrastructure by attenuating impaired glucose tolerance, reducing oxidative stress and inflammation.

Comparative study on proximate, functional, mineral, and antinutrient composition of fermented, defatted, and protein isolate of Parkia biglobosa seed.

The use of plant-derived foods in the prevention, treatment, and management of metabolic diseases especially diabetes has gained prominence; this has been associated with their physicochemical properties. This study was conducted to compare the proximate, functional, mineral, and antinutrient composition of the fermented seeds, the defatted seeds, and the protein isolate from Parkia biglobosa seeds. The results showed that the fermented, defatted, and protein isolate varied in composition within the parameters studied. The proximate analysis revealed that the protein isolate had the highest ash (6.0%) and protein (59.4%) as well as the lowest fat (5.7%) and moisture (5.1%) content when compared to the fermented and defatted samples. In like manner, the functional properties of the protein isolate were relatively better than those of the fermented and defatted samples, with oil absorption capacity of 4.2% and emulsion capacity of 82%. The magnesium and zinc content of the protein isolate were significantly higher when compared with the fermented and defatted samples, while a negligible amount of antinutrient was present in all the samples, with the protein isolate having the lowest quantity. The overall data suggest that the protein isolate had better proximate, mineral, functional, and antinutrient properties when compared to the fermented and defatted samples. Therefore, the synergistic effect of all these components present in the protein isolate from P. biglobosa seed in association with its low carbohydrate and high protein/ash contents could play a vital role in the management of diabetes and its associated complications.