Toxicological Evaluation, Ultrasound‐Assisted Phytochemicals, Antioxidant, GC – MS , FTIR , and In Vivo Analysis of Hibiscus rosa‐sinensis Flowers

ABSTRACT The application of medicinal plants in the healthcare system is a centuries‐old practice, which is proving beneficial to communities. Hibiscus rosa‐sinensis , a flowering plant in the family Malvaceae, is used for both ornamental and medicinal purposes. The current research study evaluates ultrasound‐assisted extraction (UAE) of phytochemicals, antioxidant profiling, and safety of Hibiscus rosa‐sinensis powder and methanolic extracts in an animal model. Antioxidant samples were prepared in a ratio of 1:20, with the results showing the highest 2,2‐diphenyl‐1‐picrylhydrazyl (DPPH) and 2,2′‐azinobis (3‐ethylbenzothiazoline‐6‐sulfonic acid) (ABTS) activity in the methanol extract at 86.45% and 91.12%. Functional groups were examined using a Bruker Alpha FTIR spectrometer, and the analysis revealed the presence of O–H, –COOH, C≡N, C=O, and C–H functional groups. Gas Chromatography–Mass Spectrometry (GC–MS) profiling was done using a GC/MSD thermal desorption system, and results showed major compounds with the highest percentage are 1,2‐Cyclohexanedicarboxylic acid, bis (2‐ethylhexyl) ester 2‐3‐Chlorophenoxy propionamide (25.29%), and 1,2‐Cyclohexanedicarboxylic acid, bis (2‐ethylhexyl) ester, 2‐3‐Chlorophenoxy propionamide (17.77%), respectively. For the sub‐acute toxicity study, 25 male Sprague Dawley rats were distributed in five groups and supplemented with the following doses of flower powder and extracts (Control: Placebo, Hibiscus rosa‐sinensis powder diet 1 (HRPD1): 500 mg/kg BW powder, HRPD2: 1000 mg/kg BW powder, Hibiscus rosa‐sinensis extract diet 1 (HRED1): 100 mg/kg BW extract, and HRED2: 200 mg/kg extract) for 28 days. The safety evaluation showed no adverse impact and toxic signs in animals, as the values of hematological and biochemical parameters remained in normal ranges, with no hepato‐renal changes noticed in histopathological examination. In a nutshell, Hibiscus rosa‐sinensis exhibited significant bioactive compounds and functional groups, paving the way for its application in pharmaceuticals and nutraceuticals. Moreover, the powder and extracts proved safe at this dose; however, further preclinical trials are required at a high dose to validate their safety and efficacy in clinical trials.