Ultrasound-assisted extracted dietary fibre from culinary banana bract as matrices for anthocyanin: its preparation, characterization and storage stability

Assessment of oral toxicity and safety profile of cyanidin: acute and subacute studies on anthocyanin

Aim: Purified anthocyanins lack a detailed safety profile, prompting the need for comprehensive oral toxicity research. Materials & methods: Sprague-Dawley rats aged 8 weeks received 300 mg/kg cyanidin orally for 14 days in acute toxicity (OECD 423). In the subacute study (OECD 407), adult SD rats were administered 7.5, 15 and 30 mg/kg/day cyanidin orally for 28 days. Results: Acute toxicity indicated an LD50 exceeding 300 mg/kg/day without adverse effects. Subacute toxicity at 7.5-30 mg/kg/day showed well-tolerated responses in both genders. No significant alterations in organ weights, hematological parameters, liver/kidney functions or adverse histopathological findings were observed. Conclusion: Oral cyanidin administration demonstrated high safety and tolerance in rats, establishing a NOAEL at 30 mg/kg/day, affirming cyanidin's safety for oral use.

Cyanidin Ameliorates Bisphenol A-Induced Alzheimer's Disease Pathology by Restoring Wnt/β-Catenin Signaling Cascade: an In Vitro Study

Alzheimer's disease (AD) is a progressive neurodegenerative disorder causing memory loss and cognitive decline, linked to amyloid-beta (Aβ) plaques and hyperphosphorylated tau protein accumulation in the brain. Environmental pollutant bisphenol A (BPA) has been implicated in AD pathology due to its neurotoxic effects. This study aims to evaluate cyanidin from flower bracts of Musa acuminata Colla (red variety; AAA group) for its neuroprotective properties against BPA-induced AD pathology. The extraction of cyanidin was optimized using 70% ethanol in acidified water, showing promising anti-acetylcholinesterase activity. Cyanidin was effectively purified from the resultant extract and characterized using spectroscopic techniques. Two gradient doses of cyanidin (90 and 10 µg/ml) were determined based on cell viability assay. The role of cyanidin in promoting nerve growth and differentiation was assessed in PC12 cells for up to 72 h. A discernible and statistically significant difference was assessed in neurite extension at both doses at 72 h, followed by pre-treatment with cyanidin. BPA stimulation significantly increased the p-tau expression compared to the control (p < 0.0001). Pre-treatment with cyanidin reduced the tau expression; however, a significant difference was observed compared to control cells (p = 0.0003). Cyanidin significantly enhanced the mRNA expression of Wnt3a (p < 0.0001), β-catenin (p = 0.0004), and NeuroD1 (p = 0.0289), and decreased the expression of WIF1(p = 0.0040) and DKK1 (p < 0.0001), which are Wnt antagonist when compared to cells stimulated with BPA. Conclusively, our finding suggests that cyanidin could agonize nerve growth factor and promote neuronal differentiation, reduce tau-hyperphosphorylation by restoring the Wnt/β-catenin signaling cascade, and thereby render its neuroprotective potential against BPA-induced AD pathology.

Natural Sources of Food Colorants as Potential Substitutes for Artificial Additives

In recent years, the demand of healthier food products and products made with natural ingredients has increased overwhelmingly, led by the awareness of human beings of the influence of food on their health, as well as by the evidence of side effects generated by different ingredients such as some additives. This is the case for several artificial colorants, especially azo colorants, which have been related to the development of allergic reactions, attention deficit and hyperactivity disorder. All the above has focused the attention of researchers on obtaining colorants from natural sources that do not present a risk for consumption and, on the contrary, show biological activity. The most representative compounds that present colorant capacity found in nature are anthocyanins, anthraquinones, betalains, carotenoids and chlorophylls. Therefore, the present review summarizes research published in the last 15 years (2008-2023) in different databases (PubMed, Scopus, Web of Science and ScienceDirect) encompassing various natural sources of these colorant compounds, referring to their obtention, identification, some of the efforts made for improvements in their stability and their incorporation in different food matrices. In this way, this review evidences the promising path of development of natural colorants for the replacement of their artificial counterparts.

Development of biodegradable active films based on longan seed starch incorporated with banana flower bract anthocyanin extracts and applications in food freshness indication

The recovery of food by-products is of great significance. Food by-products contain diverse materials showing promise for the development of food packaging or edible coatings. In the present study, the effects of banana flower bract anthocyanin extracts (BFBAEs) on properties of longan seed starch (LSS) films were investigated for the first time. The prepared BFBAEs presented great compatibility with LSS matrix without changing the film chemical structures. The LSS films containing BFBAEs presented improved UV light barrier capacities, increased water vapor permeability, and lowered thermal stability compared to the pure LSS films. Additionally, the introduction of BFBAEs significantly reduced tensile strength and increased elongation at break of LSS films. There is growing demands for the fabrication of intelligent films for the visible monitoring of food freshness. BFBAEs imparted great antioxidant activities and pH-sensitive and ammonia-sensitive discoloration capacities on LSS films. LSS/BFBAEs III films were employed to detect food (beef and shrimp) freshness, and distinguishable color variations could be observed as the food freshness reduced. The LSS-based films were almost completely degraded after 30 days. Two types of by-products were combined to develop novel biodegradable active films, which showed promise for the discernible detection of the freshness of perishable foods.

Effect of combination of ultrasonic treatment and anti-solvent methods as a high-efficiency method of nanoparticle production on the tragacanth gum properties

Gum tragacanth nanoparticles were prepared using a combination of intense ultrasound energy and anti-solvent precipitation methods in this research. Results showed that smaller particles were produced by increasing sonication time. As well, increasing the sonication power led to smaller particles, however, increased aggregation. Accordingly, tragacanth solutions with 0.5 and 1% (w/v) concentrations were prepared and mixed with ethanol (ratio 1:10 v/v) after ultrasound treatment with two different drop-wise and direct methods to investigate the effect of anti-solvent addition method on the precipitation of tragacanth particles. The nanoparticle images showed that the concentration of the 0.5% tragacanth solution and the direct mixing method was suitable for particle production with desirable size (72 ± 10 nm) and uniformity. FTIR, XRD, and STA studies showed that the tragacanth chemical composition did not change, and only its particle size decreased. Investigation of wettability showed a contact angle of 88.9 ± 1.7 degrees for nanoparticles providing partial wetting of the particles at the interface. Investigation of the solution viscosities of 0.5% tragacanth gum and tragacanth nanoparticles showed that the viscosity of the nanoparticles solution was significantly lower than that of the tragacanth (p < 0.05) indicating the intense effect of ultrasonication on this property. It can be concluded that the high viscosity of tragacanth gum is not due to its chemical composition but is due to its complex structure.