Effects of Rhizopus-arrhizus-31-Assisted Pretreatment on the Extraction and Bioactivity of Total Flavonoids from Hibiscus manihot L.

The Hibiscus manihot L. (HML) Medic, an edible hibiscus of the Malvaceae family, is abundant with flavonoids. The study investigated how Rhizopus-arrhizus-31-assisted pretreatment affects the extraction and bioactivity of flavonoids from HML. The fiber structure of the fermented flavonoid sample (RFF) appears looser, more porous, and more disordered than the unfermented flavonoid sample (RUF). RFF demonstrates milder conditions and yields higher extraction rates. According to the Box-Behnken response surface optimization experiment, the optimal conditions for RFF include a material-liquid ratio of 1:41 g/mL, a 2 h extraction time, a 57% ethanol concentration, and an extraction temperature of 800 °C, resulting in a 3.69% extraction yield, which is 39.25% higher than that of RUF. Additionally, RFF exhibits greater activity than RUF in the radical-scavenging system. The IC50 values for DPPH, OH, and ABTS radicals are 83.43 µg/mL and 82.62 µg/mL, 208.38 µg/mL and 175.99 µg/mL, and 108.59 µg/mL and 75.39 µg/mL for RUF and RFF, respectively. UPLC-QTOF-MS analysis of the active components in the HML flavonoid sample revealed significant differences in the chromatograms of RUF and RFF, indicating that biofermentation led to substantial changes in composition and content from HML.

Biofabricated Green Synthesized Hibiscus Silver Nanoparticles Potentiate Antibacterial Activity and Cytotoxicity in Human Lung Cancer Cells.

Traditional medicine has long employed the shrub Hibiscus sabdariffa to treat a variety of illnesses. The biochemical characteristics of silver nanoparticles made using the plant extract of Hibiscus sabdariffa were examined in this work. According to the results, the plant extract of Hibiscus sabdariffa had a total phenolic quantity of 84.9 mg/gm and a total quantity of flavonoids of 41.50 mg/gm. The extract also showed antibacterial action against Escherichia coli and Staphylococcus aureus (75.15% scavenging activity). The silver nanoparticles of plant extracts were stable in PBS solution for at least 30 days and had a mean size of particles of 21.22 nm. Silver nanoparticles were shown to both be cytotoxic on human lung cancer cell line A-549 and have anti-inflammatory action. Overall, the research's findings demonstrate the fascinating biological activity of the silver nanoparticles made from the extract of the Hibiscus sabdariffa plant. To assess these compounds' potential as medicines, more research is required.

Targets and Effects of Common Biocompounds of Hibiscus sabdariffa (Delphinidin-3-Sambubiosid, Quercetin, and Hibiscus Acid) in Different Pathways of Human Cells According to a Bioinformatic Assay.

The utilization of food as a therapeutic measure for various ailments has been a prevalent practice throughout history and across different cultures. This is exemplified in societies where substances like Hibiscus sabdariffa have been employed to manage health conditions like hypertension and elevated blood glucose levels. The inherent bioactive compounds found in this plant, namely, delphinidin-3-sambubioside (DS3), quercetin (QRC), and hibiscus acid (HA), have been linked to various health benefits. Despite receiving individual attention, the specific molecular targets for these compounds remain unclear. In this study, computational analysis was conducted using bioinformatics tools such as Swiss Target Prediction, ShinnyGo 0.77, KEGG, and Stringdb to identify the molecular targets, pathways, and hub genes. Supplementary results were obtained through a thorough literature search in PubMed. DS3 analysis revealed potential genetic alterations related to the metabolism of nitrogen and glucose, inflammation, angiogenesis, and cell proliferation, particularly impacting the PI3K-AKT signaling pathway. QRC analysis demonstrated interconnected targets spanning multiple pathways, with some overlap with DS3 analysis and a particular focus on pathways related to cancer. HA analysis revealed distinct targets, especially those associated with pathways related to the nervous system. These findings emphasize the necessity for focused research on the molecular effects of DS3, QRC, and HA, thereby providing valuable insights into potential therapeutic pathways.

Determination of anthocyanins, organic acids, and phenolic acids in hibiscus market products using LC/UV/MS.

Hibiscus sabdariffa has gained increasing attention from consumers as a natural, healthy food ingredient, leading to a myriad of available products, yet there is a lack of understanding of the quality and chemical diversity among commercially available hibiscus products. Here, we conducted a survey on the chemistry of 29 hibiscus products (calyces, beverages, and extracts). UHPLC-DAD and UHPLC-QQQ/MS methods with high sensitivity and selectivity were developed to evaluate the chemical profiles pertaining to the sensory attributes (color and taste). Two major anthocyanins (delphinidin-3-sambubioside and cyanindin-3-sambubioside), eight organic acids, and 23 phenolic acids were identified and quantified in hibiscus market products. The results showed that hibiscus samples contained < 0.001-2.372% of total anthocyanins, 0.073-78.002% of total organic acids, and 0.001-1.041% of total phenolic acids, and demonstrated significant variations in market products. This is the first time that an in-depth organic acid profiling was conducted on hibiscus products using UHPLC-QQQ/MS. This method can also be extended to chemical profiling, sensory analysis, quality control, authentication, and standardization of other natural products.

Examination of Hibiscus sabdariffa's bioactive arsenal: pharmacological prospects and comprehensive insights into catalysing health and wellness through its therapeutic attributes-an exposition.

This study signifies the rich pharmacological potential of Hibiscus sabdariffa, exploring its bioactive components and their therapeutic implications for health and wellness. Despite the promising insights, a comprehensive critical analysis is essential to ensure scientific rigour. To address this, the study establishes clear aims and objectives, aiming to scrutinise the study findings through a meticulous assessment. In conclusion, this study, upon addressing these key points, aspires to offer a robust contribution to scientific research, by advancing the understanding of H. sabdariffa's therapeutic attributes and promoting the adoption of sustainable methodologies in scientific research.

Medicinal herbs, especially Hibiscus sabdariffa, inhibit oral pathogenic bacteria.

OBJECTIVES: Medicinal herbs are plants with potential medicinal and health benefits. In recent years, they are being increasingly used as a treatment alternative owing to their effectiveness against various diseases. In this study, we investigated the inhibitory effects of 15 medicinal herbs on causative bacteria for dental caries and periodontal disease. METHODS: This study evaluated the effects of the extracts of 15 medicinal herbs on growth and biofilm formation in five oral pathogenic bacterial strains. The herbs were processed into extracts, and bacterial strains were cultured. Then, bacterial growth and biofilm formation were assessed using various methods. Finally, the extract of the herb Hibiscus sabdariffa (hibiscus) was analyzed using high-performance liquid chromatography. RESULTS: Incubation of bacteria with the herbal extracts showed that hibiscus exerted a significant inhibitory effect on all the oral pathogenic bacterial strains evaluated in this study. In addition, the pigment delphinidin-3-sambubioside, which is found in hibiscus extract, was identified as a particularly important inhibitory component. CONCLUSIONS: These results lay the ground work for the potential development of novel therapeutic or preventive agents against dental caries and periodontal disease, two major oral diseases.

Possible protective anticancer effect of chloroform fraction of Iraqi Hibiscus tiliaceus L. leaves extract on diethylnitrosamine-induced hepatocarcinogenesis in male rats.

OBJECTIVES: We aimed to examine the potential protective effects of Iraqi H. tiliaceus L. chloroform leaves extract on DEN-induced HCC in male Wistar Albino rats. METHODS: Rats were assigned to four groups, six in each group. Group I: rats were administered a daily oral dose of 1 mL/kg/day of distilled water. Group II: rats were intraperitoneally injected with 70 mg/kg DEN once per week for 10 consecutive weeks. Group III: rats received 250 mg/kg of chloroform leaves extract. Groups IV: the rats were administered 500 mg/kg of chloroform leaves extract, along with their food, for five days per week over 20 weeks, with a subsequent dose of DEN once per week for 10 consecutive weeks. RESULTS: The results indicate that the extract demonstrated a significant reduction (p<0.05) in oxidative stress, pro-inflammatory mediators, and HCC parameters, the extract also had a beneficial effect on liver function tests, and there was a significant elevation (p<0.05) of antioxidant parameters in a dose-dependent manner. CONCLUSIONS: This study supports the protective properties of the chloroform extract of Iraqi H. tiliaceus L. leaves in HCC.

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.

The bioprotective role of irradiated hibiscus against harmful effects of using repeatedly frying edible oil / O papel bioprotetor do hibisco irradiado contra os efeitos nocivos do uso de óleo comestível para fritar

Abstract Repeatedly frying process of dietary edible oil has a potential role in the generation of free radicals. Therefore, questions have always been raised as to whether, there is an efficient and economical method to reduce the harmful effects of repeated use of frying edible oil. Since hibiscus has been stated to have a wide variety of therapeutic effects, it was important to investigate its properties against harmful effects of free radicals. The current study aspires to find out whether irradiated powder of hibiscus has a protective role against adverse effects of repeated use of frying edible oil. Thirty-five adult male albino rats were equally assigned into five groups. First group"G1" was fed with normal diet as control group, meanwhile, group"G2" the diet mixed with fresh oil, "G3" diet mixed with repeatedly frying oil only, "G4" diet mixed with frying oil treated with hibiscus and "G5" diet mixed with frying oil treated with irradiated hibiscus. Feeding duration was six weeks. Fatty acid analyses of oil as well as peroxide values were determined. Blood and liver samples were collected for biochemical analyses as well as histological study. Repeatedly heated cooked oil has significant increases in peroxide value, acid value, free fatty acid and both conjugated diene and triene compared with repeatedly frying oil treated with hibiscus. Also there are significant increases in cholesterol and triglyceride and impaired in liver functions in "G3"compared with others. In addition, relative to the hibiscus groups, there is a substantial reduction in oxygen consumption in "G3". Both hibiscus as well as irradiated hibiscus attract attention in order to play a vital and economical role against harmful effects of frequent use of frying edible oil on some biological functions but, irradiated hibiscus was more effective.

Resumo O processo de fritura repetida de óleo comestível da dieta tem papel potencial na geração de radicais livres que podem ter efeitos prejudiciais em algumas funções biológicas. Portanto, sempre se questionou se existe uma maneira eficiente e econômica de prevenir ou pelo menos reduzir os efeitos nocivos do uso repetido de óleo comestível para fritar. Como o hibisco tem ampla variedade de efeitos terapêuticos, foi importante investigar suas propriedades como agente antioxidante contra os efeitos nocivos dos radicais livres. O presente estudo pretende descobrir se o pó irradiado de hibisco tem papel protetor contra os efeitos adversos do uso repetido de óleo comestível para fritar. Trinta e cinco ratos albinos machos adultos foram divididos igualmente em cinco grupos. O primeiro grupo "G1" foi alimentado com dieta normal como grupo controle, enquanto o grupo "G2" dieta misturada com óleo fresco, dieta "G3" misturada com óleo de fritura repetida, dieta "G4" misturada com óleo de fritura tratada com hibisco e dieta "G5" misturada com óleo de fritura tratada com hibisco irradiado. A duração da alimentação foi de seis semanas. Foram determinadas as análises de ácidos graxos de óleo, bem como os valores de peróxidos. Amostras de sangue e fígado foram coletadas para análises bioquímicas e estudo histológico. O óleo cozido repetidamente aquecido tem aumentos significativos no valor de peróxido, valor de ácido, ácido graxo livre e dieno e trieno conjugados em comparação com óleo de fritura repetidamente tratado com hibisco. Também há aumentos significativos no colesterol e triglicérides e comprometimento das funções hepáticas no "G3" em comparação com outros. Além disso, em relação aos grupos de hibiscos, há uma redução substancial no consumo de oxigênio no "G3". Tanto o hibisco como o hibisco irradiado chamam atenção por desempenhar papel vital e econômico contra os efeitos nocivos do uso frequente de óleo comestível para fritar em algumas funções biológicas, mas o hibisco irradiado foi mais eficaz.

Potential anti-obesity effects of two-graded doses of Iraqi Hibiscus tiliaceus leaves extract, alone and in combination with orlistat, on high-fat diet-induced obesity in male rats.

Obesity is a world health concern and a serious risk factor for several chronic diseases. Hibiscus tiliaceus is a plant with reported anti-obesity properties. However, the preclinical anti-obesity effect of ethanolic extract of Iraqi Hibiscus tiliaceus has not been studied yet. This study aimed to evaluate the preclinical anti-obesity properties of Iraqi Hibiscus tiliaceus extract, alone or in combination with orlistat, on high-fat diet-induced obesity in male rats. Male rats were divided into five groups: control, induction, ethanolic extract of Iraqi Hibiscus tiliaceus (250 mg/kg and 500 mg/kg), orlistat (Xenical) alone (10 mg/kg), and a combination of the extract (250 mg/kg) with Xenical. The rats were fed a high-fat diet to induce obesity, and treatments were given orally for 8 weeks. Body weight, food intake, serum lipid profile, and liver enzymes were measured. Administration of ethanolic extract of Iraqi Hibiscus tiliaceus (250 mg/kg and 500 mg/kg), Xenical alone (10 mg/kg), and combination with the extract (250 mg/kg) for 8 weeks significantly reduced body weight, food intake, serum triglycerides, total cholesterol, low-density lipoprotein cholesterol, and liver enzymes (aspartate transaminase and alanine transaminase) when compared to the induction group. The ethanolic extract of Iraqi Hibiscus tiliaceus showed anti-obesity effects and could be a potential therapeutic agent in managing obesity. However, further studies are needed to evaluate its clinical efficacy and safety.

Embryological observations on seed abortion in Hibiscus syriacus L. and physiological studies on nutrients, enzyme activity and endogenous hormones.

Under natural conditions, most Hibiscus syriacus L. individuals form very few mature seeds or the mature seeds that do form are of poor quality. As a result, seed yield is poor and seeds have low natural germinability. These phenomena strongly hinder utilization of the excellent germplasm resources of H. syriacus. The study has shown that pollen activity and stigma receptivity were high on the day of anthesis, and the pistils and stamens were fertile. Pollen release and stigma receptivity were synchronous. But in styles following self and cross-pollination, pollen tube abnormalities (distortion and twisting of the pollen tubes) and callose deposition were observed. Cross-pollinated pollen tubes elongated faster and fewer pollen tube abnormalities were observed compared with self-pollinated pollen tubes. And during embryo development, abnormalities during the heart-shaped embryo stage led to embryo abortion. Imbalance in antioxidant enzyme activities and low contents of auxin and cytokinin during early stages of embryo development may affect embryo development. Therefore, a low frequency of outcrossing and mid-development embryo abortion may be important developmental causes of H. syriacus seed abortion. Nutrient deficiencies, imbalance in antioxidant enzyme activities, and a high content of abscisic acid at advanced stages of seed development may be physiological causes of seed abortion.

Potential use of red hibiscus flower extract for the production of spray-chilled microparticles: Characterization, stability, and bioaccessibility in vitro of anthocyanins.

Microparticles (MLP) containing red hibiscus flower (Hibiscus rosa-sinensis) anthocyanins were produced by spray chilling, and characterized for physicochemical parameters, accelerated stability, and gastrointestinal release profile. Fully hydrogenated palm oil and cocoa butter were used as wall materials, at a lipid blend to hibiscus extract ratio of 70:30 (w/w). The lipid blends containing fully hydrogenated palm oil (FHPO) and cocoa butter (CB) were produced by ultrasound-assisted technique in the following FHPO to CB ratios: 100:0 (Control), 75:25, 50:50, 60:40, and 40:60. Increasing the cocoa butter content reduced the melting temperature and increased the unstable polymorphic behavior of the microparticles, resulting in amorphous characteristics. The microparticles exhibited higher viscosity, more agglomerates, and holes on the surface, and greater diameters. Characteristic peaks corresponding to the hibiscus extract were observed in the infrared spectra of the spray-chilled microparticles, indicating that the microencapsulation did not affect the anthocyanins. The antioxidant capacity of the red hibiscus anthocyanins ranged from 75 % to 79 %, with the best result observed for the treatment MLP_75:25. Higher antioxidant activities were observed for the lipid blends containing lower cocoa butter concentrations. Concerning the release profile of anthocyanins, the simulated GI digestion in vitro showed reduced release in the gastric tract and more intense release in the intestinal tract for an effective absorption of the antioxidant compounds in the small intestine. Furthermore, the treatment MLP_75:25 showed the highest encapsulation retention and lower total color difference in the accelerated stability study. Overall, the microparticles from all treatments were light-sensitive and thermosensitive at 35 °C. Thus, it is recommended to store the particles in a dark environment at temperatures below 35 °C for an effective use of the microparticles as natural food colorants.

Bioavailability of bioactive compounds in Hibiscus sabdariffa beverage as a potential anti-inflammatory.

The absorption and metabolism of bioactive compounds (BCs) in a Hibiscus sabdariffa drink (HbD) were evaluated by the in vivo bioavailability of organic acids (OA) and phenolic compounds (PC's). An acute single-blind clinical study in humans was conducted. Twelve volunteers consumed a HbD and a control drink (CD). Urine and plasma samples were taken after consuming both beverages. OA and PC's of the beverages (HbD and CD) and the biological samples (urine and plasma) were characterized by HPLC-DAD-MS. Thirthy-eight compounds in HbD and four CD were detected and quantified, equivalent to 937.37 mg and 1.22 mg per 60 mL, respectively. Hibiscus acid was the most abundant OA in both drinks. Additionally, hydroxycinnamic acids, flavonoids, anthocyanins, and anthocyanidins were also detected in HbD, although their amount represented 10% of the total BCs. 25 different metabolites were identified, 15 in urine and 23 in plasma. The microbiota extensively biotransformed PCs and their amount was lower than organic acids, particularly hibiscus acid and hydroxycitric acid. The colonic metabolites derived from PCs and organic acids would be behind the anti-inflammatory bioactivity described for Hibiscus sabdariffa L. (Malvaceae family). However, further studies are necessary to evaluate the metabolites responsible for their anti-inflammatory activity.

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.

Advanced interactional characterization of the inhibitory effect of anthocyanin extract from Hibiscus sabdariffa L. on apple polyphenol oxidase.

In this study, a comprehensive approach to advance the inhibitory effect of Hibiscus sabdariffa extract on apple polyphenol oxidase (PPO) was performed. PPO was extracted, purified, and characterized for optimal activity, whereas response surface methodology generated a quadratic polynomial model to fit the experimental results for hibiscus extraction. The optimum conditions allowed to predict a maximum recovery of anthocyanins (256.11 mg delphinidin-3-O-glucoside/g), with a validated value of 272.87 mg delphinidin-3-O-glucoside/g dry weight (DW). The chromatographic methods highlighted the presence of gallic acid (36,812.90 µg/g DW extract), myricetin (141,933.84 µg/g DW extract), caffeic acid (101,394.07 µg/g DW extract), sinapic acid (1157.46 µg/g DW extract), kaempferol (2136.76 µg/g DW extract), and delphinidin 3-O-ß-d-glucoside (226,367.08 µg/g DW extract). The inactivation of PPO followed a first-order kinetic model. A temperature-mediated flexible fit between PPO and anthocyanins was suggested, whereas the molecular docking tests indicated that PPO is a good receptor for cafestol, gallic acid, and catechin, involving hydrophobic and hydrogen bond interactions. PRACTICAL APPLICATION: It is well known that enzymatic browning is one of the most important challenges in the industrial minimal processing of selected fruit and vegetable products. Novel inhibitors for polyphenol oxidase are proposed in this study by using an anthocyanin-enriched extract from Hibiscus sabdariffa L. Based on our results, combining the chemical effect of phytochemicals from hibiscus extract with different functional groups with minimal heating could be an interesting approach for the development of a new strategy to inhibit apple polyphenol oxidase.

Antioxidant Capacity of Polar and Non-Polar Extracts of Four African Green Leafy Vegetables and Correlation with Polyphenol and Carotenoid Contents.

In sub-Saharan Africa, chronic malnutrition is often associated with intestinal inflammation and oxidative stress. African green leafy vegetables (GLVs), commonly consumed by these populations and rich in bioactive compounds, may improve the antioxidant status. The aim of this study was to measure the antioxidant capacity using complementary assays (DPPH, FRAP, ABTS, ORAC and NO scavenging) in polar and non-polar leaf extracts of four African GLVs, cassava (Manihot esculenta), roselle (Hibiscus sabdariffa), jute mallow (Corchorus olitorius), and amaranth (Amaranthus spp.), with spinach (Spinacia oleracea) chosen as a reference. Their antioxidant capacity was correlated with their total polyphenol (TPC), flavonoid (TFC), condensed tannin, lutein, and ß-carotene contents. Identification of phenolic compounds by UHPLC-DAD-MS/MS revealed the presence of three main classes of compound: flavonols, flavones, and hydroxycinnamic acids. Cassava and roselle leaves presented significantly higher TPC and TFC than amaranth, jute mallow, and spinach. They also exhibited the highest antioxidant capacity, even higher than that of spinach, which is known for its important antioxidant effect. The antioxidant capacity was 2 to 18 times higher in polar than non-polar extracts, and was more strongly correlated with TPC and TFC (R > 0.8) than with ß-carotene and lutein contents. These findings provide new data especially for cassava and roselle leaves, for which studies are scarce, suggesting an appreciable antioxidant capacity compared with other leafy vegetables.

Hibiscus-cisplatin combination treatment decreases liver toxicity in rats while increasing toxicity in lung cancer cells via oxidative stress- apoptosis pathway.

Cisplatin (CIS) is a broad-spectrum anti-carcinogen that causes cytotoxic effects both in normal and cancer cells. The purpose of this study was to test whether Hibiscus sabdariffa (HS) extract can reduce CIS-induced hepatotoxicity in rodents and to assess its anticancer activity in vitro. Treatment with HS extract at daily doses of 500 mg/kg before and after a single dose of CIS (10 mg/kg) reduced hepatotoxicity in Wistar male albino rats. HS extract reduced activity of hepatic damage marker enzymes ( i.e. alanine and aspartate aminotransferases), necrosis, and apoptosis in liver tissues of CIS-treated rats. This hepatic protection was associated with reduced oxidative stress in liver tissues. The antioxidant effects of HS were manifested as a normalization of malondialdehyde levels and glutathione levels which were all raised after CIS-induction. In addition, HS treatment resulted in a decrease of catalase, and superoxide dismutase activity. The combined effects of CIS and HS were also studied in two human lung cancer cell lines (A549 and H460). Treatment with HS (20 µg /mL) enhanced the cytotoxic activity of CIS both in A549 and H460 cell lines. Interestingly, HS increased CIS-induced apoptosis and oxidative stress more clearly in A549 cells indicating that HS extract in combination with CIS could increase the efficacy of CIS in the treatment of cancer.

Effect of dietary supplementation with Diuripres® on blood pressure, vascular health, and metabolic parameters in individuals with high-normal blood pressure or stage I hypertension: The CONDOR randomized clinical study.

Our aim was to evaluate if a nutritional intervention with a dietary supplement (Diuripres®) containing magnesium, standardized extract of orthosiphon, hawthorn, and hibiscus could positively affect blood pressure (BP), vascular health, and metabolic parameters in 60 individuals with high-normal BP or stage I hypertension. Participants followed a low-fat low-sodium Mediterranean diet for 4 weeks before being randomly allocated to 8-week treatment with two pills each day of either Diuripres® or placebo. Diuripres® significantly decreased systolic BP compared to placebo after 4 weeks (3.1 ± 0.8 mmHg; p < 0.05) and more consistently after 8 weeks (3.4 ± 0.9 mmHg; p < 0.05). At 8-week follow-up, after correction for multiple testing, dietary supplementation with Diuripres® was associated with significant improvements in diastolic BP (-3.1 ± 0.6 mmHg; p < 0.05), aortic BP (-4.3 ± 0.4 mmHg; p < 0.05), and high-sensitivity C-reactive protein (hs-CRP; 0.04 ± 0.01 mg/dL; p < 0.05) in comparison with baseline. The reductions in diastolic BP (--3.8 ± 0.7 mmHg; p < 0.05), aortic BP (-5.2 ± 1.0 mmHg; p < 0.05), and hs-CRP (-0.03 ± 0.01 mg/dL; p < 0.05) were also significant compared to placebo. Therefore, our study shows that dietary supplementation with Diuripres® may be useful in individuals with high-normal BP or stage I hypertension.

The Phytoestrogenic Effect of Hibiscus sabdariffa Involves Estrogen Receptor α in Ovariectomized Wistar Rats.

The calyxes of Hibiscus sabdariffa present multiple pharmacological effects primarily attributed to their high anthocyanin content; however, little is known about their phytoestrogenic effect. Ovarian hypofunction (OH) is a process characterized by the rapid detention of the production of ovarian hormones, which compromises reproductive and cognitive functions. Hormone replacement therapy (HRT) efficiently compensates for OH; nevertheless, questions have been raised on its secondary effects and safety. One of the alternatives to tackling OH involves using phytoestrogens such as anthocyanins for their structural similarity to natural estrogens. In a Wistar rat model of ovariectomy (OVX), we recently reported the beneficial properties of an anthocyanin-rich extract prepared from the calyces of H. sabdariffa (HSE) in hindering the adverse effects of OH on memory performance and highlighted a possible phytoestrogenic impact through the modulation of estrogen receptor (ER) expression. We now report that HSE and estradiol differentially affected the expression of ERα and ERß. ERα was more sensitive to HSE; meanwhile, estradiol preferentially modulated ERß. Thus, our study leads to further research on using H. sabdariffa as a nutrition-based alternative to HRT.

Antioxidant evaluation and computational prediction of prospective drug-like compounds from polyphenolic-rich extract of Hibiscus cannabinus L. seed as antidiabetic and neuroprotective targets: assessment through in vitro and in silico studies.

BACKGROUND: Reports have implicated diabetes mellitus (DM) and Alzheimer's disease (AD) as some of the global persistent health challenges with no lasting solutions, despite of significant inputs of modern-day pharmaceutical firms. This study therefore, aimed to appraise the in vitro antioxidant potential, enzymes inhibitory activities, and as well carry out in silico study on bioactive compounds from polyphenolic-rich extract of Hibiscus cannabinus seed (PEHc). METHODS: In vitro antioxidant assays were performed on PEHc using standard methods while the identification of phytoconstituents was carried out with high performance liquid chromatography (HPLC). For the in silico molecular docking using Schrodinger's Grid-based ligand docking with energetics software, seven target proteins were retrieved from the database ( https://www.rcsb.org/ ). RESULTS: HPLC technique identified twelve chemical compounds in PEHc, while antioxidant quantification revealed higher total phenolic contents (243.5 ± 0.71 mg GAE/g) than total flavonoid contents (54.06 ± 0.09 mg QE/g) with a significant (p < 0.05) inhibition of ABTS (IC50 = 218.30 ± 0.87 µg/ml) and 1, 1-diphenyl-2-picrylhydrazyl free radicals (IC50 = 227.79 ± 0.74 µg/ml). In a similar manner, the extract demonstrated a significant (p < 0.05) inhibitory activity against α-amylase (IC50 = 256.88 ± 6.15 µg/ml) and α-glucosidase (IC50 = 183.19 ± 0.23 µg/ml) as well as acetylcholinesterase (IC50 = 262.95 ± 1.47 µg/ml) and butyrylcholinesterase (IC50 = 189.97 ± 0.82 µg/ml), respectively. Furthermore, In silico study showed that hibiscetin (a lead) revealed a very strong binding affinity energies for DPP-4, (PDB ID: 1RWQ) and α-amylase (PDB ID: 1SMD), gamma-tocopherol ( for peptide-1 receptor; PDB ID: 3C59, AChE; PDB ID: 4EY7 and BChE; PDB ID: 7B04), cianidanol for α-glucosidase; PDB ID: 7KBJ and kaempferol for Poly [ADP-ribose] polymerase 1 (PARP-1); PDB ID: 6BHV, respectively. More so, ADMET scores revealed drug-like potentials of the lead compounds identified in PEHc. CONCLUSION: As a result, the findings of this study point to potential drug-able compounds in PEHc that could be useful for the management of DM and AD.