Enhancing the recovery and concentration of polyphenols from camu-camu (Myrciaria dubia H.B.K. McVaugh) by aqueous two-phase flotation and scale-up process

Progress in the technology of solvent flotation

Solvent flotation primarily relies on the variations in the activity of substances to adsorb target compounds onto the surface of bubbles, thereby facilitating the process of separation and extraction. This technology has the advantages of high separation efficiency, gentle process, and simple operation, making it widely applicable across various fields. This article reviews relevant research from the past decade to analyze the factors influencing this technology. Additionally, it provides a comprehensive overview of its applications in detecting organic matter in environmental samples and extracting bioactive compounds from natural products, while also anticipating upcoming trends in its development.

Use of sisal industrial waste (Agave sisalana Perrine) in sustainable and multifunctional cosmetic products

OBJECTIVE

Sisal is a common stiff fibre produced around the world, corresponding to approximately 70% of the commercial production of all fibres of this type. The fibres are extracted from the leaves of Agave sisalana, from which approximately 4% of their weight is obtained, with the remaining 96% considered to be residues from the process of the sisal industry. The objective of this work was to obtain a polyphenol-enriched extract from the A. sisalana residue by ultrasonically assisted extraction, characterize it chemically, evaluate in vitro antioxidant activity, and develop safe and stable photoprotective formulations for future application in cosmetic preparations.

METHODS

Ultrasonic extraction of solid plant material was performed using 50% ethanol/water (v/v). The extract was chemically characterized by high-performance liquid chromatography equipment associated with classical molecular networking and evaluated for in vitro antioxidant activity by different methodologies. Ten formulations were prepared, varying the component concentrations and the shear time. The 1.0% sisal extract was incorporated into the most stable formulations, and preliminary and accelerated stability were evaluated. The emulsions were investigated for safety by assessment of primary accumulated dermal irritability and sensitization and a dermatological clinical study of phototoxicity and photosensitization. The photoprotective formulations containing or not containing the extract that were stable after 90 days had their in vivo sun protection factor (SPF), UVA protection factor, critical wavelength, and protection against visible and blue light determined.

RESULTS

Ultrasound extraction using 50% ethanol/water (EH 50) as an extractor vehicle showed the best yield. The extract exhibited a concentration of phenolic compounds (77.93 mg of equivalent to the standard gallic acid/g) and showed in vitro antioxidant activity. Emulsions without and with 1.0% sisal extract remained stable and safe. The addition of the extract to the photoprotective formulation statistically increased the SPF when compared to the formulation without the extract and offered protection against UVA radiation, critical wavelengths, and absorption of visible and blue light.

CONCLUSION

Based on the findings, the solid residue of A. sisalana may be indicated as a component of photoprotective and antioxidant cosmetic formulations.

Purification of linarin and hesperidin from Mentha haplocalyx by aqueous two-phase flotation coupled with preparative HPLC and evaluation of the neuroprotective effect of linarin

The volatile oil of Mentha haplocalyx is widely used in medicine, food, and cosmetics. However, a large amount of its residue after steam extraction of volatile oil is abandoned, resulting in a waste of resources. The method of aqueous two-phase flotation coupled with preparative high-performance liquid chromatography was established for the separation and purification of nonvolatile active compounds from Mentha haplocalyx for the first time. The parameters of the two-phase aqueous flotation were optimized. Under the optimal conditions including flotation solvent PEG 1000 aqueous solution (1:1, w/w), pH 5, (NH₄ )₂ SO₄ concentration of 350 g/L in aqueous phase, N₂ flow rate of 20 mL/min, and flotation time of 20 min, the flotation efficiency of linarin, hesperidin, and didymin was 82.24, 76.38, and 89.33%, respectively. The linarin and hesperidin with the high purities of 95.8 and 97.2%, respectively, were obtained by using preparative high performance liquid chromatography. The neuroprotective effect of linarin against H₂ O₂ -induced oxidative stress in rat hippocampal neurons was investigated. The experimental result indicated that linarin could alleviate H₂ O₂ -induced oxidative stress. The work indicated that the combination of aqueous two-phase flotation and preparative high performance liquid chromatography is a feasible and practical method for the purification of nonvolatile active substances from Mentha haplocalyx, which would provide a reference process for the comprehensive utilization of M. haplocalyx. Especially, linarin might be used as a good source of natural neuroprotectants.

Fermented yellow mombin juice using Lactobacillus acidophilus NRRL B-4495: Chemical composition, bioactive properties and survival in simulated gastrointestinal conditions

The purpose of the present study was to evaluate yellow mombin (Spondias mombin L.) juice as a vehicle for the Lactobacillus acidophilus NRRL B-4495 probiotic. The initial pH and fermentation temperature conditions were optimized by central composite rotational design. The beverage was evaluated for its chemical composition, bioactive properties, microbiological stability, survival in simulated gastrointestinal conditions and sensory analysis. The ideal conditions for probiotic juice production were an initial pH of 6.4 and 16 h of fermentation, with maximum viability of 12.9 ± 0.4 Log CFU/mL. The fermented juice showed a total phenolic concentration of 94.90 ± 7.12 GAE/mL and antioxidant activity, as measured by DPPH (0.31 ± 0.00 μmol TE/mL) and ABTS sequestration (2.59 ± 0.30 μmol TE/mL). Antibacterial activity could also be observed against S. aureus, E. coli and K. pneumoniae. The obtained formulation showed good microbiological stability when stored at 4ºC for 28 days. In addition, there was no significant change in viability after exposure to simulated gastrointestinal conditions. The sensory analysis showed that the probiotic beverage was not well accepted. However, the Just-About-Right (JAR) ideal scale test enabled identifying the specific attributes which need to be improved from the tasters’ point of view so that it is possible to improve product acceptance.