Pradip Babanrao Dhamole

The enduring problem of kidney stone disease continues to afflict humans worldwide, with its recurrence being the most worrisome factor. Among the variety of stone-forming compounds, uric acid has received less attention despite being a significant contributor to the development of kidney stones. Throughout history, natural plant derivatives have served as a low-cost alternative for treating kidney stones. Ocimum tenuiflorum L. (Tulsi) is an indigenous medicinal plant primarily found in the Indian subcontinent and has gained recognition for its efficacy in managing various ailments, particularly kidney stones. The current investigation delves into the inhibitory capability of tulsi extract on in vitro uric acid crystallization. The addition of tulsi extract to synthetic urine resulted in a delay in the induction of uric acid crystallization and a decrease in the uric acid crystal size in a concentration dependent manner. At pH 5, a 19 fold increase in the induction time and a 3 fold decrease in the crystal size were observed when the concentration of tulsi extract was increased from 27.5 to 110 µg/mL. The current study effectively illustrates the inhibitory potential of tulsi extract in curbing uric acid crystallization.

Present work investigates kinetics, thermodynamics and solubilization isotherm of cloud point extraction of lycopene (CPEL) using non-ionic surfactant L62. The kinetics of CPEL has been found to follow pseudo second order with a regression coefficient of 0.99. The experimental data have been fitted to Langmuir adsorption isotherm (R2 = 0.97) and Freundlich adsorption isotherm (R2 = 0.96). Surfactant concentration required to extract a given amount of lycopene predicted using Langmuir isotherm is comparable with experimental results (R2 = 0.96). Thermodynamic parameters obtained for CPEL are: ΔH°= 86.22 kJ/mol and ΔS° = 0.290 kJ/mol K. ΔG° is negative for the investigated temperature range (65-85 °C). Lycopene stability data in coacervate phase suggests that the rate of lycopene degradation is best described by a second order kinetic model. Thus, the storage medium found to have influence on lycopene degradation/isomerisation in the surfactant phase.

The extraction of lutein from marigold petals using a surfactant-based aqueous two-phase system is reported. In this work, the effectiveness of the hydrophilic-lipophilic balance of surfactants on extraction performance for the extraction of lutein from marigold petal powder was demonstrated using aqueous solutions of a wide range of non-ionic surfactants. The response surface methodology was applied to obtain optimised conditions for maximum extraction of lutein. At the optimised conditions (Temperature = 37.5 °C, S/L = 0.00375, and surfactant amount = 1.5% (v/v)), 12.12 ± 0.16 mg/g of lutein was obtained. Furthermore, the surface morphology of marigold petal powder (MPP) was analysed using SEM micrographs. Significant changes in surface morphology were observed which suggested better access of surfactant solution to the targeted biomolecule implanted in the matrix. Finally, the antioxidant activity of the obtained lutein extract was analysed using 2,2-diphenyl-1-picrylhydrazyl (DPPH). Results suggest that the antioxidant activity of the lutein extract obtained by the surfactant-based system is more than that of the lutein extract obtained by organic solvents. The aforementioned results suggest that the lutein can be extracted using a surfactant-based aqueous two-phase system (ATPS).

This paper reports the extraction of soluble dietary fibre (SDF) and seed oil, from tomato peel and seed respectively. SDF was extracted using the alkaline extraction method, while the oil was extracted by a surfactant-assisted aqueous extraction method (SAAE). The alkaline extraction method reported for papaya peels is optimised in the present work for tomato peels. Maximum SDF yield of 17.2 g/ 100 g of defatted peel was achieved with the following extraction conditions: NaOH 1% (w/w); temperature 50°C; solid/liquid (L/S) 50:1 and time 60 min. Extracted SDF showed a low molar mass of 1.27×10⁶ Da which is desirable as it helps in the formation of a gel. For SAAE, surfactants were screened from a range of surfactants (L61, L62, L64, Tween 80, and Triton X-100). Out of these, L62, at 1% (v/v) concentration showed 70% (w/w) extraction yield in a single-stage extraction with a L/S ratio of 25:1. SDF and oil yield obtained from these methods were higher than previously reported extraction techniques. Thus, both the alkaline extraction and SAAE were found to be better methods for SDF and seed oil extraction respectively. GRAPHICAL ABSTRACT

This study reports the sugaring-out extraction of erythromycin from fermentation broth using acetonitrile (ACN) as solvent and glucose as a mass separating agent. Different process parameters—glucose concentration, temperature, ACN/water ratio and pH—were optimized to achieve maximum extraction of erythromycin. 88% (w/w) of erythromycin was extracted from the model system with following optimized conditions: glucose 156.3 g/L; temperature 4 °C; ACN/water ratio 1 and pH 8.3. Further, the effect of typical fermentation media components (starch, soybean flour, CaCO₃, NaCl and (NH₄)₂SO₄) on sugaring out extraction of erythromycin was also investigated. Starch, soybean flour and CaCO₃ were observed to affect erythromycin extraction only at higher concentration. Removal of suspended solids from simulated as well as real broth prior to extraction enhanced the extraction efficiency (from 72% to 87%). Sugaring out extraction of erythromycin was found to be more effective than salting out extraction. Also, higher partition coefficient was achieved in the present work than other reported methods using carbohydrates as mass separating agent. Further, it was found that the antimicrobial activity of erythromycin was preserved during sugaring out extraction of erythromycin.