Box-Behnken Response Surface Design of Polysaccharide Extraction from Rhododendron arboreum and the Evaluation of Its Antioxidant Potential.

Ajaz Ahmad,Hamed A El-Serehy,Muneeb U Rehman,Parvaiz Ahmad,Tahir Maqbool Mir,Adil Farooq Wali,Fahad A Al-Misned,Saleh N Maodaa,Hossam M Aljawdah

doi:10.3390/molecules25173835

Abstract

In the present investigation, the ultrasound-assisted extraction (UAE) conditions and optimization of Rhododendron arboreum polysaccharide (RAP) yield were studied by a Box–Behnken response surface design and the evaluation of its antioxidant potential. Three parameters that affect the productivity of UAE, such as extraction temperature (50–90 °C), extraction time (10–30 min), and solid–liquid ratio (1–2 g/mL), were examined to optimize the yield of the polysaccharide percentage. The chromatographic analysis revealed that the composition of monosaccharides was found to be glucose, galactose, mannose, arabinose, and fucose. The data were fitted to polynomial response models, applying multiple regression analysis with a high coefficient of determination value (R2 = 0.999). The data exhibited that the extraction parameters have significant effects on the extraction yield of polysaccharide percentage. Derringer’s desirability prediction tool was attained under the optimal extraction conditions (extraction temperature 66.75 °C, extraction time 19.72 min, and liquid–solid ratio 1.66 mL/g) with a desirability value of 1 yielded the highest polysaccharide percentage (11.56%), which was confirmed through validation experiments. An average of 11.09 ± 1.65% of polysaccharide yield was obtained in optimized extraction conditions with a 95.43% validity. The in vitro antioxidant effect of polysaccharides of R. arboreum was studied. The results showed that the RAP extract exhibited a strong potential against free radical damage.

Highlights

Rhododendron arboreum (RA) is a small tree or evergreen shrub of the family Ericaceous
In the present investigation, we demonstrate the effect of the ultrasound-assisted extraction (UAE) of process variables, such as the extraction temperature, time, and solid–liquid ratio, on the percentage yield of Rhododendron arboreum polysaccharide (RAP) using Box–Behnken design (BBD), and its in vitro anti-oxidant potential
The chromatographic analysis revealed that the composition of monosaccharides was found to be glucose (RT 15.739 min), galactose (RT 16.587), mannose (RT 17.514), arabinose (RT 18.303), and fucose (RT 18.569) (Figure 1B)

Summary

Introduction

Rhododendron arboreum (RA) is a small tree or evergreen shrub of the family Ericaceous. R. arboreum young leaves cause intoxication if consumed in large quantities, as well as having medicinal uses, and can be applied on the forehead to ease a headache [6,7]. This plant is not listed for its harmful effects [8]; the likelihood of it harming humans is tremendously low. R. arboreum flowers with a sweet and sour taste are used in the preparation of squash, jams, jellies, and local brewing in hilly areas It can make a very popular and enjoyable cocktail, drank as a soothing appetizer once a day and can even be used to avoid sickness at high altitudes [6]. Plant-derived polysaccharides have received interest for their variety of medicinal properties, such as being antioxidant and antitumor; having immunological, antimicrobial, and anti-hyperlipidemic activity; and having almost no adverse effects on human health [10,11,12]

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Results

Conclusion