Antioxidant and toxicity activity of aqueous extracts from various parts of breadfruit and breadnut

Two related underutilized plants from breadfruit (Artocarpus altilis) and breadnut (Artocarpus camansi) were explored for their antioxidant and toxicity potential. Maceration with water was employed for the sake of safety and easiness. Various parts of both plants, namely leaves, fruit peel, anthocarp, and breadnut achene, were investigated. The antioxidant assays employed in this study were total phenolic and flavonoid content, total antioxidant capacity, DPPH scavenging activity, power-reducing assay, and linoleic acid peroxidation inhibition. The acute toxicity potential of the extracts was assessed using inhibition of Vibrio harveyi bioluminescence. The EC50 value determined from the toxicity assessment (>2.4 mg/mL) was higher than the concentrations of all extracts used in the various assays of antioxidant property. From all aqueous extracts, the best results in terms of highest antioxidant activity and relatively lowest toxicity were obtained for breadnut leaves, breadnut achene, and breadfruit leaves

Evaluation of the antioxidant and antibacterial activity of breadnut (Artocarpus camansi Blanco) leaf extracts

Breadnut (Artocarpus camansi) was once acted as a staple food. Exploration of phytochemistry potential of this now underutilized plant was done. Total ethanol, ethyl acetate, and hexane extracts from leaves were examined for phenolic and flavonoid content, an antioxidant capacity that was related to DPPH scavenging activity, antibacterial activities using well diffusion assay, and minimum inhibitory concentration (MIC) of the best subjective extracts utilizing tetrazolium assay. There were significant differences between the results of the three crude extracts that were evaluated. The ethanol extracts showed the highest total phenolic and flavonoid content, which were 47.46 mg GAE/g dried extract and 79.094 mg CE/g dried extract, correspondingly. The ethanol extract exhibited the lowest IC50 values (73.16 mg/L) which related to the ability to scavenge DPPH. Antibacterial activity of each extract tested against Staphylococcus aureus and Escherichia coli revealed that ethanol extract gave the highest inhibition diameter significantly. The MIC values of ethanol extract ranged from 25 to 50 mg/mL. There was a strong correlation between the phenolic and flavonoid content with antioxidant and antimicrobial activity. These results revealed that the solvent’s polarity determined the phenolic and flavonoid content significantly, hence affecting antimicrobial and antioxidant activity

Identification of DNA G–quadruplex Forming Sequence in Shrimp White Spot Syndrome Virus (WSSV)

White spot syndrome virus (WSSV) is considered one of the most infectious and lethal viruses that affect shrimp. Bioinformatic studies revealed several G–quadruplex forming sequences at the open reading frame region. Moreover, the sequences are widely conserved through all deposited WSSV sequences. Introductory structural studies on two sequences, namely WSSV131 and WSSV172, are proposed to form a quadruplex. While WSSV172 forms a mixture of quadruplex topologies, WSSV131 is suggested to form a parallel topology, as indicated by the NMR spectra and circular dichroism (CD) ellipticity pattern. CD spectra also suggested that the major parallel species of the WSSV131 sequence are found to be stable above 60 °C. Ultimately, these results may open a new strategy for WSSV treatment by targeting the quadruplex confirmation with a quadruplex binding ligand

Structural Aspects of Split G-Quadruplexes in Quadruplex-Duplex Hybrid Systems

G-quadruplexes are secondary structures of nucleic acids increasingly employed for biological and also technological applications. Being of particular interest, a structural motif called quadruplex-duplex (QD) hybrid comprises both a G-quadruplex and duplex domain. Here, we attempted to engineer a bimolecular quadruplex-duplex hybrid through dual recognition of a receptor by a target strand with the simultaneous formation of both G-quadruplex and duplex structures. Three different constructs were designed for the G-quadruplex receptor, featuring either one, two, or three vacant sites. Addition of the target strand filled the vacancies when simultaneously hybridizing with flanking sequences to form a duplex as shown by NMR studies. Formed QD hybrid constructs either constitute an 11 : 1, 10 : 2, or 9 : 3 split G-quadruplex system. The 10 : 2 QD construct folds into a non-canonical V-loop topology. Remarkably, the latter also accommodates 5’-overhang residues of the target strand although suggested to impose a steric penalty. Formation of the duplex domain is demonstrated to be critical for the successful formation of the intact G-quadruplex domain. With the formation of a unique QD junction for detection, the constructs may constitute valuable tools for single strand capturing strategies

The genetic basis of high-carbohydrate and high-monosodium glutamate diet related to the increase of likelihood of type 2 diabetes mellitus: a review

Diabetes is one of the most common metabolic diseases. Aside from the genetic factor, previous studies stated that other factors such as environment, lifestyle, and paternal-maternal condition play critical roles in diabetes through DNA methylation in specific areas of the genome. One of diabetic cases is caused by insulin resistance and changing the homeostasis of blood glucose control so glucose concentration stood beyond normal rate (hyperglycemia). High fat diet has been frequently studied and linked to triggering diabetes. However, most Asians consume rice (or food with high carbohydrate) and food with monosodium glutamate (MSG). This habit could lead to pathophysiology of type 2 diabetes mellitus (T2D). Previous studies showed that high-carbohydrate or high-MSG diet could change gene expression or modify protein activity in body metabolism. This imbalanced metabolism can lead to pleiotropic effects of diabetes mellitus. In this study, the authors have attempted to relate various changes in genes expression or protein activity to the high-carbohydrate and high-MSG-induced diabetes. The authors have also tried to relate several genes that contribute to pathophysiology of T2D and proposed several ideas of genes as markers and target for curing people with T2D. These are done by investigating altered activities of various genes that cause or are caused by diabetes. These genes are selected based on their roles in pathophysiology of T2D

Aberrant PDK4 Promoter Methylation Preceding Hyperglycemia in a Mouse Model

Diabetic prevalence is at speedy increase globally. Previous studies stated that other than genetics, factors such as environment, lifestyle, and paternal-maternal condition play critical roles in diabetes through DNA methylation in specific areas of the genome. The purpose of this study is to investigate the methylation pattern of the PDK4 promoter in streptozotocin-induced diabetic mice until the 12th week of the observation. The methylation pattern in the blood samples was analyzed periodically, while the pattern in the muscle sample was only analyzed at the end of the experiment using the blood of the sacrificed animals. Three methylated CpG site 1, CpG site 6, and CpG site 7 were analyzed and quantified based on the band density using bisulfite treatment and methylation-specific polymerase chain reaction (PCR). The hyperglycemia period was developed at the 9th week of the experiment. However, there was a significant increase of methylation, specifically on CpG site 6 started from week 6 to week 12. This peculiar methylation on CpG site 6 of PDK4 promoter in the blood sample before the hyperglycemic period might serve as a potential biomarker for early detection of diabetes in the patients. No significant difference was found between the methylation level of streptozotocin (STZ)–treated mice and of the control group in the muscle sample

Valorization of Peel-Based Agro-Waste Flour for Food Products: A Systematic Review on Proximate Composition and Functional Properties

With the steadily growing world population, effective methods are needed to alleviate food shortages. One possible strategy could be to utilize agro-waste materials that accumulate in large quantities at every stage of the economic chain during harvesting, food production, and consumption. Peel-based agro-waste consists of promising materials that can be utilized to potentially substitute commonly used raw materials in products traditionally made from wheat, tapioca, and rice flours. In this systematic review, we aim at establishing prospective proximate components as basic nutrients and their valorization potential as substitutes in traditional flour products (bread, biscuits, etc.). Generally, the peel contains high levels of fiber and relatively low digestible carbohydrates, providing a healthier food ingredient. In terms of protein, it should be pointed out that seeds such as wheat utilize insoluble gluten as their major storage protein, while proteins in peel were found in quite high percentage although they were not yet well characterized. However, the general effect of using peel to substitute wheat in food products are the reduction of dough elasticity, increased hardness of the end-products, faster water absorption rate of the products, and in some cases, bitter taste and darker colors. The latter two could have been contributed by the secondary metabolites such as phenolic compounds. On the other hand, substitution of peel into food products can have valuable health benefits, e.g., retention of antioxidant activity due to the phenolic compounds or simply adding fiber. In this review, literature on the composition of promising agro-waste raw materials is being discussed in the relationship with physical properties and appearance of potential end-products. Antinutritional compounds and pretreatment processes are also being considered. It is hoped that a critical discussion will lead to a better understanding and higher acceptance of the incorporation of peel into food products

Structural and thermodynamic studies of G-quadruplexes with unique structural motifs and their recognition by small molecules

This dissertation explores and tries to unravel the fundamental basis of G-quadruplex end-folding as well as G-quadruplex interactions with small molecules by thermodynamic and structural approaches. Selective targeting of G-quadruplexes with ligands remains elusive, either because the ligand has considerable binding affinity for other DNA structures or because it fails to discriminate between different G-quadruplex topologies. Unique structural motifs on the G-quadruplex may enhance or inhibit ligand binding to the G-quadruplex. For such aspects, it is necessary to understand the effect of G-quadruplex motifs or elements on the end-folding in order to better tune certain G-quadruplex topologies as model systems. Importantly for targeting G-quadruplex with ligands, motifs called Quadruplex-duplex (QD) junctions and interfaces are shown to be a binding hotspot for various G-quadruplex ligands containing an intercalator motif. Binding affinity and selectivity of the ligands are discussed with the support of the NMR structures

High-affinity binding at quadruplex–duplex junctions: rather the rule than the exception

Quadruplex-duplex (Q–D) junctions constitute unique structural motifs in genomic sequences. Through comprehensive calorimetric as well as high-resolution NMR structural studies, Q–D junctions with a hairpin-type snapback loop coaxially stacked onto an outer G-tetrad were identified to be most effective binding sites for various polycyclic quadruplex ligands. The Q–D interface is readily recognized by intercalation of the ligand aromatic core structure between G-tetrad and the neighboring base pair. Based on the thermodynamic and structural data, guidelines for the design of ligands with enhanced selectivity towards a Q–D interface emerge. Whereas intercalation at Q–D junctions mostly outcompete stacking at the quadruplex free outer tetrad or intercalation between duplex base pairs to varying degrees, ligand side chains considerably contribute to the selectivity for a Q–D target over other binding sites. In contrast to common perceptions, an appended side chain that additionally interacts within the duplex minor groove may confer only poor selectivity. Rather, the Q–D selectivity is suggested to benefit from an extension of the side chain towards the exposed part of the G-tetrad at the junction. The presented results will support the design of selective high-affinity binding ligands for targeting Q–D interfaces in medicinal but also technological applications

Solar Based Photocatalytic Decolorization of Four Commercial Reactive Dyes Utilizing Bound TiO₂-Fe₃O₄ Nanocomposite

Dye effluent is one of the most prominent source of water contamination. This study investigated the solar based photocatalytic decolorization of four commercial reactive dyes, which are Reactive Turquoise Blue G 133, Reactive Yellow M4g, Reactive Bordeaux B, and Reactive Red M8b using immobilized TiO2-Fe3O4 on three kind of binders as the support, specifically cyanoacrylate glue, oil-based paint, and white Portland cement on PVC plate. TiO2-Fe3O4 was synthesized using sol-gel method and placed in muffle furnace at 773 K. The composite of TiO2-Fe3O4 was characterized using SEM-EDX and XRD. White cement emerged as the best binder in term of the color removal efficiency of all four dyes compared to other binders, which were more than 90% color removal after 3 h of solar irradiation. Moreover, there was significant enhancement on color removal using immobilized photocatalyst on white cement compared to mobile photocatalyst. The kinetic of the decolorization performance followed the pseudo-first-order reaction. The apparent reaction rate constant was found to decrease along with the increase of the dye concentration. The photodecolorization kinetics fitted the Langmuir-Hinshelwood model. These protocols and results can be applied into textile industrial primary wastewater treatment using solar as a sustainable light and energy source