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Wound healing effects of biogenic gold nanoparticles synthesized using red wine extracts
No full textGold nanoparticles (AuNPs) were synthesized using three red wine extracts (RW-Es); by varying temperature, pH, concentrations of RW-Es and gold salt. The RW-AuNPs were characterized by UV–vis, transmission electron microscopy (TEM), dynamic light scattering (DLS), and the Fourier Transform Infra-red Spectroscopy (FT–IR). Their stability was evaluated in water, foetal bovine serum (FBS), phosphate-buffered saline (PBS), and Dulbecco’s Modified Eagle Medium (DMEM) by UV–Vis. The effect of the RW-Es and RW-AuNPs on KMST-6 cell cell viability was evaluated by MTT assay; and their wound healing effects were monitored by scratch assay. RW-AuNPs synthesis was observed by colour change, and confirmed by UV–Vis spectrum, with an absorption peak around 550 nm. The hydrodynamic sizes of the RW-AuNPs ranged between 10 and 100 nm. Polyphenols, carboxylic acids, and amino acids are some of functional groups in the RW-Es that were involved in the reduction of RW-AuNPs. The RW-AuNPs were stable in test solutions and showed no cytotoxicity to the KMST-6 cells up to 72 h. AuNPs synthesized from Pinotage and Cabernet Sauvignon enhanced proliferation of KMST-6 cells and showed potential as wound healing agents. Further studies are required to investigate the molecular mechanisms involved in the potential wound-healing effect of the RW-AuNPs
Implications of ecological drivers on roan antelope populations in Mokala National Park, South Africa
No full textClimate change has massive global impacts and affects a wide range of species. Threatened species such as the roan antelope (Hippotragus equinus) are particularly vulnerable to these changes because of their ecological requirements. Attempts to address concerns about the roan’s vulnerability have not been well documented in South African protected areas. This study identifies the landscape use and distribution of the roan as well as habitat and forage suitability changes to help inform management decisions for the conservation of roan. We used fine- and broad-scale data from Mokala National Park, South Africa that includes roan occurrence data, vegetation condition indices, vegetation (structure and plant species composition), elevation and temperature differences, and precipitation strata to construct a suitability framework using the Maximum Entropy (Maxent) and Random Forest statistical package. In Mokala National Park, roan occurred in the Schmidtia pappophoroides–Vachellia erioloba sparse woodland, Senegalia mellifera–Vachellia erioloba closed woodland, Senegalia mellifera–Vachellia tortilis open shrubland, Vachellia erioloba–V. tortilis closed woodland and Rhigozum obovatum–Senegalia mellifera open shrubland. The veld (vegetation) condition index (VCI) improved from 2019 (VCI 60%), with the proportion of palatable grass species (Schmidtia pappophoroides and Eragrostis lehmanniana) also increasing. This study identified four key climatic conditions affecting roan distribution, namely annual mean daily temperature range, temperature seasonality, minimum temperatures of the coldest month, and precipitation of the wettest month. These results suggest that the conservation of roan antelope should consider these key variables that affect their survival in preferred habitats and foraging areas in anticipation of changing ecological conditions
Nutritional, biochemical, and functional properties of pearl millet and moringa oleifera leaf powder composite meal powders
No full textThis study sought to improve pearl millet’s nutritional, functional, and biochemical properties through malting and fermentation. Moringa oleifera leaf powder (MLP) was used as a fortificant. Mixture design was used to find optimal proportions for each component that yielded a high protein and or low saturated fat content. Twelve mixtures with varying ratios of fermented and malted pearl millet flour ranging between 30–65% and MLP between 5–15% were generated through I-Optimal mixture design. The mixtures were wet-cooked, freeze-dried, and analysed for protein and fat content. The data obtained were fitted to a linear mixture model, and the search for the optimum was conducted using Numerical Optimisation for maximising protein and minimising saturated fat. The linear model was suitable for explaining total protein and saturated fat variation with r2 of 0.50 and 0.51, respectively. Increasing MLP increased protein content. Two final formulations, Optimisation Solution 1 (OS1) and Optimisation Solution 2 (OS2), were generated through the optimisation process. Pearl millet’s protein content increased by up to 22%, while saturated fat decreased by up to 13%; ash content increased by 75%. Polyphenol content and oxygen radical absorbance capacity increased by 80% and 25%, respectively. Final and peak viscosity were reduced by 90% and 95%, respectively
One-pot synthesis optimization of thiol-capped SnS and SnS/ZnS QDs for photocatalytic degradation of Rhodamine 6G
No full textInterest in SnS-based quantum dots (QDs) has increased due to their low toxicity, widespread natural availability, and superior electro-optical characteristics suitable for photodegradation applications. Herein, we report the synthesis of SnS-based QDs using thiourea and tin (II)chloride as salt precursors. The study explored the impact of various synthetic parameters such as pH, capping ligand, Sn:S ratio, reaction solvent, and ZnS shell on the optical characteristics of the synthesized QDs. The optimal QDs properties were observed at pH = 3 and Sn:S ratio = 1:1. Transmission electron microscopy analysis showed spherical nanoparticles, while the Fourier Transform Infrared spectroscopy revealed QDs with thiol capping. Time-dependent studies revealed that when the QDs were synthesized using propylene glycol, the ultraviolet-visibile (UV–vis) spectrum exhibited an increase in absorbance over time and improved stability compared to aqueous synthesized QDs. SnS/ZnS QDs capped with 3-mercaptopropanoic acid exhibited improved photoluminscence (PL) emissions, stability, and aqueous dispersion compared to glutathione and l-Cysteine as thiol-capping agents. The photocatalytic activity of SnS/ZnS QDs was assessed against Rhodamine 6G and increased to 65 % when passivated with ZnS compared to 31 % for the core SnS QDs. With the given findings, this study supports the stability and effectiveness of the SnS/ZnS QDs as a viable dye degradant
The protective role of resveratrol against high glucose-induced oxidative stress and apoptosis in HepG2 cells
No full textHigh glucose concentrations result in oxidative stress, leading to damage of cellular constituents like DNA, proteins, and lipids, ultimately resulting in apoptosis. Resveratrol, a polyphenol phytoalexin, has been studied for its potential therapeutic effects on diabetes. This study investigated the influence of high glucose (HG) on HepG2 cells and assessed resveratrol's effect on high-glucose-induced oxidative stress and apoptosis. HepG2 cells were cultured for 48 and 72 h with high glucose (40 mM), low resveratrol (25 μM), high resveratrol (50 μM), high glucose + low resveratrol, and high glucose + high resveratrol. After exposure, oxidative and apoptosis-related gene expression was evaluated using quantitative polymerase chain reaction (qPCR), and lactate dehydrogenase (LDH) release was measured using the supernatant. In HepG2 cells cultured with high glucose, all antioxidant enzymes (SOD, superoxide dismutase; GPx1, glutathione peroxidase 1; CAT, catalase; Nrf2, nuclear factor erythroid 2–related factor 2; and NQO1, NAD(P)H quinone oxidoreductase 1) were significantly reduced; however, when HepG2 cells were cultured with resveratrol (25 and 50 μM) and high glucose, the expression levels of all antioxidant enzymes were increased. The anti-apoptotic gene (B-cell lymphoma 2; Bcl2) and the DNA repair gene (Oxoguanine glycosylase-1, OGG1) were significantly decreased following high glucose exposure to HepG2 cells. Surprisingly, the expression levels of Bcl2 and OGG1 were notably elevated after resveratrol treatment. Furthermore, high glucose levels increased the LHD release in HepG2 cells, whereas resveratrol treatment reduced the LDH release. Our results demonstrate that resveratrol provides protection against oxidative stress and apoptosis induced by high glucose in HepG2 cells. Hence, resveratrol shows potential as an effective approach to address the impaired antioxidant response resulting from elevated glucose levels commonly observed in diabetes and metabolic disorders
Phytonanotherapy for the treatment of metabolic dysfunction-associated steatotic liver disease
No full textMetabolic dysfunction-associated steatotic liver disease (MASLD), previously known as nonalcoholic fatty liver disease, is a steatotic liver disease associated with metabolic syndrome (MetS), especially obesity, hypertension, diabetes, hyperlipidemia, and hypertriglyceridemia. MASLD in 43–44% of patients can progress to metabolic dysfunction-associated steatohepatitis (MASH), and 7–30% of these cases will progress to liver scarring (cirrhosis). To date, the mechanism of MASLD and its progression is not completely understood and there were no therapeutic strategies specifically tailored for MASLD/MASH until March 2024. The conventional antiobesity and antidiabetic pharmacological approaches used to reduce the progression of MASLD demonstrated favorable peripheral outcomes but insignificant effects on liver histology. Alternatively, phyto-synthesized metal-based nanoparticles (MNPs) are now being explored in the treatment of various liver diseases due to their unique bioactivities and reduced bystander effects. Although phytonanotherapy has not been explored in the clinical treatment of MASLD/MASH, MNPs such as gold NPs (AuNPs) and silver NPs (AgNPs) have been reported to improve metabolic processes by reducing blood glucose levels, body fat, and inflammation. Therefore, these actions suggest that MNPs can potentially be used in the treatment of MASLD/MASH and related metabolic diseases. Further studies are warranted to investigate the feasibility and efficacy of phytonanomedicine before clinical application
Carbon dioxide hydrate inhibition by tetramethylammonium chloride + glycerol deep eutectic solvent
No full textGas hydrate formation is undesirable in flow assurance
processes, as their formation can lead to the clogging of pipelines. Additives
can be added to oil and gas streams to act as thermodynamic or kinetic
inhibitors. Most currently utilized additives are either toxic or environ mentally unfriendly. In a quest for more environmentally friendly
alternatives, deep eutectic solvents (DES) were investigated in this study.
Hydrate dissociation conditions for systems comprising water + carbon
dioxide + tetramethylammonium chloride/glycerol were measured using the isochoric pressure search method. Temperatures
ranging from 275 to 284 K and pressure ranging from 2 to 4 MPa were considered with deep eutectic solvent compositions from 10
to 20 wt %. The objective of this study was to analyze the efficiency of deep eutectic solvents as carbon dioxide gas hydrate
inhibitors. The experimental data reported in this study indicated inhibitory effect,, depending on the concentration of the deep
eutectic solvents used in this study. Experimental results are discussed in terms of the effect of the DES composition on the phase
behavior under hydrate forming conditions. Data reported in this study can be used to develop thermodynamic models for DES
containing systems, as well as to better understand the effect of the structure of deep eutectic solvents on gas hydrate formation
Green synthesis of gold nanoparticles using liquiritin and other phenolics from glycyrrhiza glabra and their anti-inflammatory activity
No full textPhenolic compounds are the main phytochemical constituents of many higher plants. They play an important role in synthesizing metal nanoparticles using green technology due to their ability to reduce metal salts and stabilize them through physical interaction/conjugation to the metal surface. Six pure phenolic compounds were isolated from licorice (Glycyrrhiza glabra) and employed in synthesizing gold nanoparticles (AuNPs). The isolated compounds were identified as liquiritin (1), isoliquiritin (2), neoisoliquiritin (3), isoliquiritin apioside (4), liquiritin apioside (5), and glabridin (6). The synthesized AuNPs were characterized using UV, zeta sizer, HRTEM, and IR and tested for their stability in different biological media. The phenolic isolates and their corresponding synthesized NP conjugates were tested for their potential in vitro cytotoxicity. The anti-inflammatory effects were investigated in both normal and inflammation-induced settings, where inflammatory biomarkers were stimulated using lipopolysaccharides (LPSs) in the RAW 264.7 macrophage cell line. LPS, functioning as a mitogen, promotes cell growth by reducing apoptosis, potentially contributing to observed outcomes. Results indicated that all six pure phenolic isolates inhibited cell proliferation. The AuNP conjugates of all the phenolic isolates, except liquiritin apioside (5), inhibited cell viability. LPS initiates inflammatory markers by binding to cell receptors and setting off a cascade of events leading to inflammation. All the pure phenolic isolates, except isoliquiritin, neoisoliquiritin, and isoliquiritin apioside inhibited the inflammatory activity of RAW cells in vitro
Impact of chronic consumption of herbal rooibos on cardiovascular function in adults with cardiovascular risk
No full textThe prevalence of cardiovascular disease (CVD) has increased in South Africa, emphasizing the importance of prevention strategies. This study used echocardiography to investigate the impact of Rooibos on cardiovascular function in those at risk of CVD. This research aims to contribute to understanding its effects on reducing cardiovascular risk factors. The study design involved a 12-week randomized, parallel, double-blinded, placebo-controlled dietary intervention trial using capsules containing standardized water-soluble extracts of green and traditional fermented Rooibos alongside a placebo control. Echocardiography was incorporated as a diagnostic imaging tool to assess cardiac function in the participant cohort. Aorta (AO) dimensions showed no significant change in any intervention group. Left atrium (LA) reduced in size from 3.832 ± 0.071 cm to 3.675 ± 0.067 cm (P = 0.01). There was no significant change in LA/AO ratio in any intervention group. Interventricular septum diameter in the placebo group decreased from 1.334 ± 0.030 cm to 1.250 ± 0.025 cm (P = 0.002), with no significance in fermented Rooibos, while green Rooibos resulted in a decrease from 1.282 ± 0.036 cm to 1.186 ± 0.029 cm (P = 0.002). Left ventricle posterior wall (LVPW) showed no significant changes in any of the intervention group. The left ventricle mass in the placebo and green Rooibos groups demonstrated no significance changes, while fermented Rooibos caused a decrease from 204.102 ± 7.102 g to 191.394 ± 6.707 g (P = 0.015). The phytochemical bioactive components, such as the polyphenolic antioxidants present in green and fermented Rooibos, improved cardiovascular function. This study confirms the effectiveness of echocardiography as imaging tool for assessing cardiac function in this particular population. Regular Rooibos consumption may offer promising therapeutic benefits for preventing and managing CVD risk
Expression, purification, and characterisation of recombinant alginate lyase (Flammeovirga AL2) for the bioconversion of alginate into alginate oligosaccharides
No full textAlginate, a polysaccharide found in brown seaweeds, has regularly gained attention for its potential use as a source of bioactive compounds. However, it is structurally complex with a high molecular weight, limiting its application. Alginate oligosaccharides (AOS) are small, soluble fragments, making them more bioavailable. Alginate hydrolysis by enzymes is the preferred method for AOS production. Commercially available alginate lyases are limited, expensive, and sometimes exhibit unsatisfactory activity, making the search for novel alginate lyases with improved activity indispensable. The aims of this study were to codon-optimise, synthesise, express, purify, and characterise a recombinant alginate lyase, AL2, from Flammeovirga sp. strain MY04 and to compare it to a commercial alginate lyase. Expression was successfully performed using Escherichia coli ArcticExpress (DE3) RP cells, and the protein was purified through affinity chromatography. The recombinant enzyme was characterised by pH optimum studies, and temperature optimum and stability experiments. The optimal reaction conditions for AL2 were pH 9.0 and 37 °C, while for the commercial enzyme, the optimal conditions were pH 8.0 and 37 °C. At optimal reaction conditions, the specific activity of AL2 was 151.6 ± 12.8 µmol h−1 mg−1 protein and 96.9 ± 13.1 µmol h−1 mg−1 protein for the commercial alginate lyase. Moreover, AL2 displayed impressive activity in breaking down alginate into AOS. Hence, AL2 shows potential for use as an industrial enzyme for the hydrolysis of alginate into alginate oligosaccharides. Additional studies should be carried out to further characterise this enzyme, improve its purity, and optimise its activity