Phenolic content, antioxidant and antifungal activities of acetonic, ethanolic and petroleum ether extracts of Hypericum perforatum L

Hypericum perforatum: a comprehensive review on pharmacognosy, preclinical studies, putative molecular mechanism, and clinical studies in neurodegenerative diseases

The herb Hypericum perforatum, also referred to as St. John's wort, has drawn a lot of interest because of its potential therapeutic benefits in treating neurodegenerative illnesses. Due to the absence of effective therapies, illnesses like Alzheimer's and Parkinson's disease pose an increasing worldwide health concern. Because of its wide variety of phytochemicals, especially hyperforin, and hypericin, Hypericum perforatum is well known for its neuroprotective properties. These substances have proven to be able to affect different cellular processes linked to neurodegeneration. They can act as anti-inflammatory, antioxidant, and neurotransmitter system regulators, which may help halt neurodegenerative illnesses' progression. The use of Hypericum perforatum extracts and its contents has shown encouraging results in research on animal models of neurodegenerative disorders. These advantages include higher nerve cell survival, lowered oxidative stress, and higher cognitive performance. Underscoring its versatile potential to combat neurodegeneration, Hypericum perforatum has neuroprotective mechanisms that modulate neuroinflammation and prevent apoptotic pathways. In conclusion, Hypericum perforatum shows tremendous promise as a potential treatment for neurological illnesses due to its wide variety of phytochemicals. To completely comprehend its specific mechanisms of action and turn these discoveries into efficient clinical therapies, additional research is needed. Investigating Hypericum perforatum's function in neurodegenerative disorders may present new opportunities for the advancement of ground-breaking therapeutic strategies.

Distribution of total phenols, flavonoids and hypericin in different plant organs of wild-growing St. John’s-wort (Hypericum perforatum L., Hypericaceae) from North Macedonia

Hypericum perforatum L. (Hypericaceae) contains secondary metabolites that show noteworthy pharmacological activities. Therefore, the content of total phenols, flavonoids and hypericin from whole herb, flowers and leafs from St. John’s-wort collected over four consecutive seasons (2014-2017) from three different locations in western part of North Macedonia (Tetovo, Debar and Mavrovo) were investigated by three different spectrophotometric methods (using Folin-Ciocalteu reagent, NaNO2-AlCl3-NaOH and mixture of water/tetrahydrofuran). The quantity of total phenols obtained from different plant organs (leafs, whole herb and flowers) were 35.15-83.08 mg GAE/g, 55.41-98.52 mg GAE/g and 75.44-121.19 mg GAE/g, respectively. Afterword the total flavonoids contents were: 61.64-106.86 mg CE/g, 73.04-117.57 mg CE/g and 108.65-125.35 mg CE/g in leafs, whole herb and flowers, respectively, while the hypericin amounts were: 0.03-0.17 mg/g, 0.04-0.29 mg/g and 0.07-0.60 mg/g in leafs, whole herb, and flowers, respectively. Significant differences were observed in the quantities of total phenols, flavonoids and hypericin between the locations of harvesting, while the collection seasons were found not to be significant. Additionally, it can be seen that the flowers are characterized by higher amounts of total phenols, total flavonoids and hypericin compared to total herb and leaf in all three locations, therefore harvesting of St. John’s-wort should be made in a manner of obtaining larger quantities of flowers as harvesting material which could increase the bioactive compounds in the herbal row material. Keywords: Hypericum perforatum, plant organs, total phenols, flavonoids, hypericin, statistical analysis

Antifungal properties of hypericin, hypericin tetrasulphonic acid and fagopyrin on pathogenic fungi and spoilage yeasts

CONTEXT

The role of hypericin-mediated photodynamic antimicrobial properties on pathogenic fungi and photodynamic therapy for human cancer cells is known. Antifungal properties of Hypericum perforatum L. (Hypericaceae) and Fagopyrum esculentum Moench. (Polygonaceae) extracts were also studied. The different polarities of solvents can cause complication in the identification of antifungal effects of separate biologically active compounds. In recent experimental work, we compared antifungal properties of purified hypericin, hypericin tetrasulphonic acid (hypericin + S) and fagopyrin, which is analogue of hypericin.

OBJECTIVE

The antifungal properties of aromatic polyketide derivatives such as hypericin, hypericin + S and fagopyrin on the selected pathogenic fungi and spoilage yeasts have been studied.

MATERIALS AND METHODS

The antifungal properties of hypericin, hypericin + S and fagopyrin were determined using the broth microdilution method against a set of pathogenic fungi and spoilage yeasts including: Microsporum canis, Trichophyton rubrum, Fusarium oxysporum, Exophiala dermatitidis, Candida albicans, Kluyveromyces marxianus, Pichia fermentans and Saccharomyces cerevisiae. The tested concentrations of hypericin, hypericin + S and fagopyrin ranged from 750 to 0.011 μg/mL and MIC values were evaluated after 48 h incubation at 30 °C.

RESULTS

The results confirm different antifungal properties of hypericin, hypericin + S and fagopyrin on the selected pathogenic fungi and spoilage yeasts. For pathogenic fungi, the minimum inhibitory concentrations of hypericin ranged 0.18-46.9 μg/mL, hypericin + S 0.18-750 μg/mL and fagopyrin 11.7-46.9 μg/mL. For spoilage yeasts, the MICs of hypericin and hypericin + S ranged 0.18-46.9 and 0.011-0.73 μg/mL, respectively.

DISCUSSION AND CONCLUSION

The results obtained herein indicate that various chemical structures of hypericin, hypericin + S and fagopyrin can develop different antifungal properties.

Nutrient Composition and In Vitro Antioxidant Properties of Harungana madagascariensis Stembark Extracts

The stembarks of Harungana madagascariensis were analyzed for their content of chemical constituents, antinutrients, vitamin levels, and in vitro antioxidant properties in two solvent systems. Phytochemical screening revealed higher levels of alkaloids, saponins, and flavonoids in the methanolic (MHM) extract than in the dichloromethane (DCM) extract. The methanolic extract had higher contents of minerals, vitamins, and antinutrients except K, vitamin B1, and phytic acid, respectively. Antioxidant potentials of the stembark extracts were assessed by the 1, 1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging activity, metal chelating activity, and ferric reducing power. The methanolic extract showed a better antioxidant activity (IC50=87.66±0.97 μg/mL) in the DPPH system. The metal chelating activity was higher in the methanolic extract (92.4% at 20 mg/mL), but lower than the control ethylenediaminetetraacetic acid (EDTA). The methanolic extract also showed greater ferric reducing power and was richer in phenolics (132.24±0.61 mgGAE/g) and flavonoids (259.05±2.85 mgQE/g). Antinutrient analysis of the extracts indicated low levels of phytic acid, oxalates, and hydrocyanides below the lethal doses. The LD50 (i.p. mice) of the extracts showed relatively low toxicity in the range 1000-1414 mg/kg. These results support the ethnomedicinal uses of this plant in the treatment of diseases related to oxidative stress and suggest that consumption of H. madagascariensis is not harmful nutritively.

Toxicology of some important medicinal plants in southern Africa

Africa is home to two major floral kingdoms: the Paleotropical kingdom of central Africa and the Capensis kingdom of the Western Cape province of South Africa, the latter of which consists of approximately 10,000 species, representing about 20% of Africa's floral 'gold mine', better known as the Cape herbal medicine. Needless to say, such rich flora comes with numerous plants with a potential to cause poisoning to humans. This review document reports important toxic medicinal plants and their toxic ingredients for plant species resident in the southern African region. These include important medicinal uses and pharmacological properties ranging from antimicrobial, antiviral, anticancer, anti-inflammatory as well as those that are used as aphrodisiacs and for maternal health care.