A Comprehensive Overview of Hibiscus rosa-sinensis L.: Its Ethnobotanical Uses, Phytochemistry, Therapeutic Uses, Pharmacological Activities, and Toxicology.

Hibiscus rosa-sinensis (H. rosa-sinensis) has been largely used in traditional medicine. This study aims to review the pharmacological and phytochemical properties of Hibiscus rosa-sinensis L and also summarize the pharmacological, photochemical, and toxicological characteristics of H. rosa-sinensis. The current review focuses on the distribution, chemical content, and main uses of H. rosa-sinensis. Various scientific databases, including ScienceDirect, Scopus, PubMed, Google Scholar, etc., were used. Correct plant names were verified from plantlist.org. The results were interpreted, analyzed, and documented based on bibliographic information. This plant has been frequently used in conventional medicine due to its high concentration of phytochemicals. All its parts contain numerous chemical compounds, such as flavonoids, tannins, terpenoids, anthocyanins, saponins, cyclopeptide alkaloids, and vitamins. More interestingly, the roots of this plant contain glycosides, tannins, phytosterols, fixed oils, fats, flavonoids, saponins, gums, and mucilages. The leaves contain alkaloids, glycosides, reducing sugars, fat, resin, and sterols. The stem contains other chemical compounds, such as ß-sitosterol, teraxeryl acetate, cyclic sterculic, and malvalic acids. Finally, the flowers contain riboflavin, thiamine, apigenidine, oxalic acid, citric acid, quercetin, niacin, pelargonidine, and ascorbic acid. This species has a wide variety of pharmacological applications, such as antimicrobial, antioxidant, antidiabetic, anti-inflammatory, antihypertensive, antifertility, antifungal, anticancer, hair growth-promoting, antihyperlipidemic, reproductive, neurobehavioral, antidepressant, and antipyretic activities. Finally, toxicological studies have shown that higher doses of extracts from the plant are safe.

Comparative taxonomical, biological and pharmacological potential of healthy and geminivirus infected leaves of Hibiscus rosa-sinensis L.: First report.

In the present research project, the first report on comparative analysis of the taxonomical, biological and pharmacological potential of healthy and geminivirus infected Hibiscus rosa sinensis (L.) leaves of the family Malvaceae was done by using different micro and macroscopic techniques. First of all, leaves were characterized for Cotton leaf curl Multan virus (CLCuMuV) and its associated betasatellite (Cotton leaf curl Multan Betasatellite; CLCuMB). Different morphological parameters like shape and size of stem, leaves, seeds and roots, presence and absence of ligule, distance between nodes and internodes and type of inflorescence etc. were analyzed. CLCuMuV infected H. rosa-sinensis revealed systematic symptoms of infection like chlorosis of leaves, stunted growth, decrease in size of roots, shoots and distortion etc. Anatomical investigation was performed under light ad scanning electron microscope. Different anatomical features like length and shape of guard cells, subsidiary cells, presence or absence of stomata, secretory ducts and trichomes were examined. In both plant samples anomocytic types of stomata and elongated, non-glandular and pointed tip trichomes were present, but the size (especially length and width) of trichomes and other cells like epidermal, subsidiary, and guard cells were highest in virus infected plants likened to healthy one. In the antibacterial activity, the maximum antibacterial potentail was seen in methanolic extract of K. pneumonea while antifungal activity was shown by methanolic extract of A. solani. Plants interact with different biological entities according to environmental conditions continuously and evolved. These types of interactions induce changes positively and negatively on plant metabolism and metabolites production. Many plant viruses also attacked various host plants consequently alter their secondary metabolism. To overcome such virus infected plants produces many important and different types of secondary plant metabolites as a defense response. Subsequent analysis of this n-hexane plant extract using Gas chromatography mass spectroscopy technique revealed that Hibiscus eluted contained 10 main compounds in Healthy sample and 13 compounds in infected one. Presence of essential secondary metabolites were also analyzed by FTIR analysis. The present study provides a comprehensive and novel review on taxonomy (morphology, anatomy) and antimicrobial potential of both healthy and geminivirus infected H. rosa-sinensis.

Application of green synthesised copper iodide particles on cotton fabric-protective face mask material against COVID-19 pandemic.

Microorganisms cause variety of diseases that constitutes a severe threat to mankind. Due to the upsurge of many infectious diseases, there is a high requirement and demand for the development of safety products finished with antimicrobial properties. The study involves the antimicrobial activity of natural cotton coated with copper iodide capped with Hibiscus rosa-sinensis L. flower extract (CuI-FE) which is rich in anthocyanin, cyanidin-3-sophoroside by ultrasonication method. The coated and uncoated cotton fabric was characterised through XRD, SEM, AFM, tensile strength and UV-Visible spectroscopic techniques. XRD confirmed the formation of CuI particles, SEM showed that CuI-FE was prismatic in shape. The average size of CuI-FE particles was found to be 552.45 nm. Anti-bacterial studies showed copper iodide particles to be a potent antimicrobial agent. AFM images confirmed the rupture of bacterial cell walls in the presence of prismatic CuI-FE. In-vitro cytotoxicity investigation of CuI-FE was performed against cancer and spleen cell lines to evaluate the cell viability. Cytotoxicity analysis revealed the IC50 value of 233.93 µg/mL in the presence of CuI-FE. Molecular docking study was also carried out to understand the interaction of CuI-FE with COVID-19 main protease. This paper has given an insight on the usage of CuI-FE coated on the cotton fabric that has proved to have strong inhibition against the nano ranged bacterial, cancerous cell line and a strong interaction with the COVID-19 protease. Such eco-friendly material will provide a safe environment even after the disposable of medical waste from the infectious diseases like influenza and current pandemic like COVID-19.

Effects of 4-CPPU on in vitro multiplication and sustainable generation of Hibiscus rosa-sinensis L. 'White Butterfly'.

There are more than nine thousand cultivars of Hibiscus rosa-sinensis L., with a series of flowers with shapes, colors and new cultivars continues as generated through both traditional and modern breeding techniques. In this study, advanced biotech methods of in vitro culture have been used to identify a technique for the efficient mass multiplication of H. rosa-sinensis 'White Butterfly', using phenyl urea, N-(2-Chloro-4-pyridyl)-N'-phenylurea (4-CPPU). For the first time, the effects of 4-CPPU for stimulating axillary shoot proliferation and multiple shoot regenerations from nodal explants were evaluated, and the optimal nutrient media deduced. From the diverse concentrations as 0.1, 0.5, 2.5, 5.0 & 10.0 µM of 4-CPPU, the highest frequency of shoots was recorded at 2.5 µM supplied in Murashige and Skoog (MS, pH-5.8) medium. After eight-weeks of culture, on an average of 6.7 shoot were obtained on this media with shoot heights of 4.2 cm from each explant. With the involvement of 0.5 µM-IBA (indole-3-butyric acid) in MS medium the regenerated shoots were rooted and followed by successful acclimation to ex vitro conditions. The ploidy consistency among the micro-plants was analyzed using flow cytometry and compared with ex vitro grown plants. No differences in the ploidy levels were observed among the 4-CPPU induced plants, when compared with the donor plants.

The N-butyl alcohol extract from Hibiscus rosa-sinensis L. flowers enhances healing potential on rat excisional wounds.

ETHNO-PHARMACOLOGICAL RELEVANCE: Hibiscus rosa-sinensis L. (HRS), a folk medicine named Zhujin in China, possess anti-tumor, antioxidant, antibacterial, low density lipoprotein oxidation prevention and macrophage death prevention effects. The leaves and red flowers of HRS have been traditionally used to treat with furuncle and ulceration. AIM OF THE STUDY: To investigate the efficacy and possible mechanism of the N-butyl alcohol extract of HRS (NHRS) red flowers in wound healing by analyzing the collagen fiber deposition, angiogenic activity and macrophages action of the NHRS. MATERIALS AND METHODS: In an excisional wound healing model in rats, different concentrations of NHRS, or recombinant bovine basic fibroblast growth factor (rbFGF), were respectively applied twice daily for 9 days. Histopathology was assessed on day 9 via hematoxylin and eosin (HE) and Masson's trichrome (MT) staining, and immunohistochemistry for vascular endothelial growth factor (VEGF), transforming growth factor-ß1 (TGF-ß1) and CD68. Immunomodulation by NHRS was evaluated by a carbon clearance test in mice. RESULTS: Wound healing post-surgery was greater in the rbFGF-control, NHRS-M and MHRS-H groups than in the model and 5% dimethylsulfoxide (DMSO)-control groups after the third day. By the sixth day the wound contraction of NHRS-M and MHRS-H groups was much higher than the rbFGF-control group. HE and MT staining revealed that epithelialization, fibroblast distribution, collagen deposition of NHRS-M- and NHRS-H-control groups were significantly higher than the model group. Moreover, immunohistochemistry showed more intense staining of VEGF, TGF-ß1 and CD68 in the rbFGF- and NHRS-control groups, compared to that in model and 5% DMSO-control groups. The clearance and phagocytic indices of NHRS-M- and NHRS-H-control groups were significantly higher than that of the carboxyl methyl cellulose (CMC) group in mice. CONCLUSION: NHRS accelerates wound repair via enhancing the macrophages activity, accelerating angiogenesis and collagen fiber deposition response mediated by VEGF and TGF-ß1.

Mechanisms Involved in Toxicity of Liver Caused by Piroxicam in Mice and Protective Effects of Leaf Extract of Hibiscus rosa-sinensis L.

Piroxicam is one of the important therapeutic nonsteroidal anti-inflammatory class of drugs used mainly to suppress pain and inflammation in arthritis and other musculoskeletal disorders. Besides being anti-inflammatory, these drugs are analgesic and antipyretic often used for the relief of nonspecific fever condition. Recently, piroxicam has also gained attention as an effective therapy for tumors, colorectal, and invasive bladder cancers. The objective of the current study is to evaluate the protective effects of the alcoholic leaf extract of Hibiscus rosa-sinensis (AEH), Malvaceae, against piroxicam-induced toxicity in mice. Sixty adult Swiss albino mice (Mus musculus) were divided into four groups (n = 10), which included a control group, a group treated orally with AEH (30 mg kg(-1) b.w.) for 15 days, a group treated orally with piroxicam (6.6 mg kg(-1) b.w.) for 15 days, and another group treated orally with piroxicam and AEH for 15 days. The results indicated that treatment with piroxicam alone resulted in a significant increase in the activities of serum marker enzymes, namely, aspartate transaminase, alanine transaminase, and alkaline phosphatase with profound hepatic lipid peroxidation as evidenced by a marked increment in the level of thoibarbituric acid reactive substances along with a distinct diminution in reduced glutathoine content and various antioxidant enzymes such as superoxide dismutase, catalase, and glutathione peroxidase in the liver. However, treatment with AEH during piroxicam treatment retrieved or partially antagonized the effects induced by piroxicam toward the normal values of controls. Histopathological observations also corroborate with the above findings. It can be concluded that AEH exhibited a protective action against piroxicam toxicity and effective in combating oxidative stress-induced hepatic damage.

Molecular characterization of phytoplasmas of 'Clover proliferation' group associated with three ornamental plant species in India.

Suspected phytoplasma symptoms of little leaf, yellowing, chlorosis, phyllody, witches' broom, and stunting were observed on ten different ornamental plant species at New Delhi, Andhra Pradesh, Haryana, Bengaluru, and Pune, India, during March to July 2016. To investigate the possibility of phytoplasma etiology, PCR assays were performed using universal primer pairs (P1/P7 followed by 3Far/3Rev) specific to the phytoplasma 16Sr RNA gene. First round PCR amplification with primer pair P1/P7 did not yield expected 1.8 kb product of 16S rRNA region from any of the 17 symptomatic samples. However, 1.3 Kb amplicons were observed in nested PCR assays with 3Far/3Rev primer pair in symptomatic leaf samples of Hibiscus rosa-sinensis L. (Pune isolate), Saponaria officinalis L. (Pune isolate), and Allamanda cathartica L. (Delhi isolate). No amplifications were observed in any of the other tested symptomatic and non-symptomatic plant samples either in first round or second round of nested PCR assays with phytoplasma specific primer pairs. Pairwise sequence comparison of 16S rDNA sequences of the five positive phytoplasma strains of A. catharica, H. rosa-sinensis, and S. officinalis in the present study revealed 99-100% sequence identities with strains of 'clover proliferation' (16SrVI) group. Phylogenetic and virtual RFLP analysis of 16S rDNA sequences of the five identified phytoplasma strains belonging to three ornamental species further confirmed their clustering and grouping with member strains of 'clover proliferation' subgroup D. This is the first record of the phytoplasma association of 'clover proliferation' subgroup D with H. rosa-sinensis, S. officinalis, and A. cathartica in the world.

Acute and sub-acute oral toxicity assessment of the methanolic extract from leaves of Hibiscus rosa-sinensis L. in mice.

BACKGROUND: The leaves of Hibiscus rosa-sinensis L. (Malvaceae) are used for the treatment of dysentery and diarrhea, to promote draining of abscesses and as analgesic agent in the traditional medicine of Cook Islands, Haiti, Japan and Mexico. AIM: The present study investigated the oral acute and subacute toxicity of methanol leaf extract of H. rosa-sinensis in mice. MATERIALS AND METHODS: In the acute toxicity study, a single oral dose of 2000 mg/kg of extract was given to five mice at 48 h intervals. Animals were observed individually for any clinical signs of toxicity or mortality for 14 days. In the sub-acute toxicity study, mice were treated with 400 mg/kg and 800 mg/kg doses of the extract for 14 days. The hematological and biochemical parameters and histopathology of liver and kidneys of animals were studied at the end of the experiment. RESULTS: For acute treatment, the extract did not reveal any signs of toxicity or mortality in any animal, during the 14 days observation period. The LD50 of extract was estimated to be greater than 2000 mg/kg. In the sub-acute toxicity study, administration of 400 mg/kg and 800 mg/kg doses of extract to mice for two weeks did not reveal any marked adverse effects on hematological, biochemical parameters and histopathology of liver and kidney in the 400 mg/kg group. However, hepato-renal toxicity as evidenced by elevated levels of alanine aminotransferase, aspartate aminotransferase, total and indirect bilirubin, urea and creatinine was seen in the animals that received 800 mg/kg dose of extract for 14 days. In addition, in the same group of animals, the histological assessments of liver and kidney also showed various adverse effects viz. dilated sinusoids, apoptotic nuclei and inflammatory infiltrate inside sinusoidal capillaries in the liver, and marked the disorganization of tubules and glomeruli, and enlarged interstitial spaces in the kidney. CONCLUSION: The results of this study suggest that for traditional medicinal purpose, only a low dose of H. rosa-sinensis leaf extract (i.e., 400 mg/kg) should be considered as safe.

Caracterização antibacteriana e fitoquímica de flores de Hibiscus rosa-sinensis L. (mimo-de-vênus) e Hibiscus syriacus L. (hibisco-da-síria) / Antibacterial and phytochemical characterization of flowers of Hibiscus rosa-sinensis L. (treat-of-venus) and Hibiscus syriacus L. (hibiscus-the-syrian)

Hibiscus rosa-sinensis e o Hibiscus syriacus são considerados flores comestíveis e estudos demonstram seu potencial antibacteriano frente a diversos micro-organismos. Este trabalho teve por objetivo analisara Intensidade de Atividade de Inibição (IINIB) e a Inativação Bacteriana (IINAB) in vitro dos extratos alcoólicos das flores dos hibiscos e a relação com os polifenóis e antocianinas revelados. Avaliou-se a ação antibacteriana frente às bactérias de interesse alimentar, Staphylococcus aureus e Salmonella Enteritidis resultando em diferenças significativas entre as médias de IINIB/IINAB, sendo S. aureus a cepa maisresistente para o H. syriacus e S. Enteritidis a mais sensível em ambos os experimentos. Com relação ao H. rosa-sinensis, este foi eficaz para ambas as bactérias. O teor dos compostos fitoquímicos presentes nas plantas constatou que há uma forte correlação positiva com a atividade antibacteriana (r = 0,88),sendo que o H. rosa-sinensis obteve poder antibacteriano maior do que o H. syriacus, presumindo estar relacionado à maior quantidade de polifenóis e antocianinas detectadas no primeiro. Conclui-se que as plantas estudadas têm poder bactericida e bacteriostático podendo agir contra a contaminação bacteriana...

Modulation of lipid peroxidation and antioxidant status upon administration of 'Shemamruthaa' in 7,12-dimethylbenz[a]anthracene induced mammary carcinoma bearing rats

Objective: To investigate the therapeutic efficacy of a Shemamruthaa (SM), (combination of Hibiscus rosasinensis (H. rosasinensis) flowers, fruits of Phyllanthus emblica (P. emblica) and pure honey in definite ratio), against lipid peroxidation (LPO) and antioxidant status in experimentally induced mammary carcinoma rats. Methods: Adult female Sprague-Dawley rats were used for the study and were divided into four groups. Group I control animals received standard pellet diet and water ad libitum. Group II rats were induced with 7,12-dimethyl benz[a]anthracene (DMBA) (25 mg in 1 mL olive oil) by gastric intubation, whereas another set of DMBA-induced rats were treated with SM (400 mg/kg body weight/d) in olive oil orally by gastric intubation for 14 d after 3 months of induction period (group III). Group IV rats served as SM-treated control animals. At the end of the experimental period, the rats were anaesthetised and sacrificed and used for biochemical measures and histology studies. Results: The LPO was increased and antioxidant levels were decreased in the serum, liver and mammary tissues of cancer-induced rats. The administration of SM drug significantly (P<0.05) decreased LPO and reversed the status of antioxidants to near normal level in cancer-bearing animals. Conclusions: The results obtained indicate the additive and synergistic action of constituents’ plants in the SM drug against oxidative damage and its protective role in DMBA induced mammary cancer.