Assessment of in vitro and in vivo antimalarial efficacy and GC-fingerprints of selected medicinal plant extracts

A review of botany, traditional applications, phytochemistry, pharmacological applications, and toxicology of Rubus ellipticus Smith fruits

Rubus ellipticus Smith. (Family Rosaceae), often known as the yellow Himalayan raspberry (Yellow Hissar), is one of the most widely used edible fruits in Indian folk medicinal systems. The current review aims to identify the gap between research and existing applications of this fruit to help scientists explore the current trends and opportunities for future development. Fruits of R. ellipticus are the source of several classes of compounds. Fruits of R. ellipticus are also rich in nutrients such as carbohydrates, vitamins, and minerals. It has been shown to have significant medical value in a variety of studies, including as an anti-diabetic, nephroprotective, anti-inflammatory, analgesic, antipyretic, antitumor, wound healing, antifertility, oviposition deterrent, antibacterial, and antioxidant. Fruits of R. ellipticus have been the subject of several in vitro and in vivo investigations, all of which have corroborated their wide range of biological activities and demonstrated their potential for the identification of new therapeutic candidates and the development of innovative herbal food supplements. Additional mechanism-based pharmacological evaluation and clinical research should provide an adequate scientific basis for the traditional usage of R. ellipticus fruits, which is currently not sufficiently supported by the available research on its active components and molecular mechanisms.

Yellow Himalayan Raspberry (Rubus ellipticus Sm.): Ethnomedicinal, Nutraceutical, and Pharmacological Aspects

Yellow Himalayan raspberry (Rubus ellipticus Sm., Rosaceae) is a native species of the Indian subcontinent, Southern China, and the Philippines, which has been historically used as a traditional medicine and food. All of the parts of this plant have been used in traditional medicine to treat respiratory ailments, diabetes, and gastrointestinal disorder, and as an anti-infective agent. The scientific evaluation revealed a richness of macronutrients, micronutrients, and minerals in the fruits, indicating its potential use as a nutraceutical. Furthermore, this plant has been found to be rich in various secondary metabolites, including polyphenols, flavonoids, anthocyanins, tannins, and terpenoids. Ascorbic acid, kaempferol, gallic acid, and catechin are some of the compounds found in this plant, which have been widely discussed for their health benefits. Furthermore, various extracts and compounds obtained from R. ellipticus have shown antioxidant, antidiabetic, anticancer, anti-inflammatory, nephroprotective, antipyretic, anticonvulsant, and anti-infective activities investigated through different study models. These findings in the literature have validated some of the widespread uses of the fruits in folk medicinal systems and the consumption of this nutritious wild fruit by local communities. In conclusion, R. ellipticus holds strong potential for its development as a nutraceutical. It can also improve the nutritional status of villagers and uplift the economy if properly utilized and marketed.

Cuscuta reflexa Possess Potent Inhibitory Activity Against Human Malaria Parasite: An In Vitro and In Vivo Study

Drug resistance to practically all antimalarial drugs in use necessitate the development of new chemotherapeutics against malaria. In this aspect, traditionally used plants with folklore reputation are the pillar for drug discovery. Cuscuta reflexa being traditionally used in the treatment of malaria in Odisha, India we aimed to experimentally validate its antimalarial potential. Different solvent extracts of C. reflexa or column fractions from a promising solvent extract were evaluated for in vitro anti-plasmodial activity against Plasmodium falciparum strain Pf3D7. Potent fractions were further evaluated for inhibition of parasite growth against different drug resistant strains. Safety of these fractions was determined by in vitro cyto-toxicity, and therapeutic effectiveness was evaluated by suppression of parasitemia and improvement in survival of experimental mice. Besides, their immunomodulatory effect was investigated in Pf-antigen stimulated RAW cells. GCMS fingerprints of active fractions was determined. Column separation of methanol extract which showed the highest in vitro antiplasmodial activity (IC₅₀ = 14.48 μg/ml) resulted in eleven fractions, three of which (F2, F3, and F4) had anti-plasmodial IC₅₀ ranging from ≤ 10 to 2.2 μg/ml against various P. falciparum strains with no demonstration of in vitro cytotoxicity. F4 displayed the highest in vivo parasite suppression, and had a mean survival time similar to artesunate (19.3 vs. 20.6 days). These fractions significantly modulated expression of inflammatory cytokines in Pf-antigen stimulated RAW cells. The findings of the study confirm the antimalarial potential of C. reflexa. Exploration of phyto-molecules in GCMS fingerprints of active fractions is warranted for possible identification of lead anti-malarial phyto-drugs.

Pharmacological and phytochemical potential of Rubus ellipticus: a wild edible with multiple health benefits

OBJECTIVES

Rubus ellipticus (family Rosaceae) is used for its delicious edible fruits in the Himalayan region and other parts of the globe. However, the full potential of the species is yet to be harnessed. The current review focuses on the phytochemical, traditional uses, morphological, molecular and pharmacological potential of R. ellipticus.

KEY FINDINGS

The review of the literature reveals that many health-promoting compounds of R. ellipticus have been reported from the species along with the different biological properties, such as nephroprotective, anti-inflammatory, analgesic, anti-pyretic, anti-proliferative, cytotoxicity, anti-cancer, wound healing, anti-fertility, anti-plasmodial, anti-microbial and antioxidant. Traditionally, it is used in many formulations, which are validated through primary pharmacological assays. However, several medicinal properties are still need to be validated through detailed pharmacological and clinical studies.

SUMMARY

All the information is available in a scanty form, and the complete information is missing on a single platform. Such type of information will help researchers to better utilize the available data for initiating future research on the species as it has the potential to contribute to the food and pharmaceutical industry. The review highlights the need for further studies on the species to harness its potential in nutraceutical, functional food, energy supplement, and beneficial therapeutic drug development program.

Antimalarial, Antioxidant Activities and Chemoprofile of Sansevieria liberica Gerome and Labroy (Agavaceae) Leaf Extract

Background

Sansevieria liberica Gerome and Labroy (Agavaceae) is a religious and ornamental perennial plant with highly valued medicinal usage in Nigeria. Sansevieria liberica is used in the management of malarial fever. The ease of development of resistance to available antimalarial drugs has resulted in increased clinical failure and mortality. The study investigated the antimalarial effects of Sansevieria liberica (SL) leaf extract in mice infected with Plasmodium berghei.

Materials and Methods

The ability of SL leaf extract to suppress the growth of malaria parasites in early (suppressive) and established (curative) infections was established using animal models. The mean survival time (MST) was determined. The antioxidant potential was established using two standard in vitro models. High-performance liquid chromatography (HPLC) and phytochemical analysis methods were used to create a chemoprofile fingerprint of SL hydroethanolic leaf extract.

Results

At 200, 400, and 400·mg kg⁻¹, SL produced 68.71, 70.74, and 75.09% parasite suppression in the suppressive model while the curative model gave a percentage of cure of 71.09, 72.60, and 62.09, respectively. The animals lived longer compared to both negative and positive controls but were not fully protected. The IC₅₀ values of SL and vitamin C were calculated to be 3.599 µg mL⁻¹ and 3.08 µg mL⁻¹, respectively. The reducing power of vitamin C was significantly (P < 0.05) higher than that of SL extract. Some flavonoids were established as possible marker compounds for SL leaf extract. Discussion and Conclusions. The antimalarial assay results demonstrated that the use of SL in folk medicine may have scientific support.

Studies on Activities and Chemical Characterization of Medicinal Plants in Search for New Antimalarials: A Ten Year Review on Ethnopharmacology

Malaria is an endemic disease that affected 229 million people and caused 409 thousand deaths, in 2019. Disease control is based on early diagnosis and specific treatment with antimalarial drugs since no effective vaccines are commercially available to prevent the disease. Drug chemotherapy has a strong historical link to the use of traditional plant infusions and other natural products in various cultures. The research based on such knowledge has yielded two drugs in medicine: the alkaloid quinine from Cinchona species, native in the Amazon highland rain forest in South America, and artemisinin from Artemisia annua, a species from the millenary Chinese medicine. The artemisinin-based combination therapies (ACTs), proven to be highly effective against malaria parasites, and considered as “the last bullet to fight drug-resistant malaria parasites,” have limited use now due to the emergence of multidrug resistance. In addition, the limited number of therapeutic options makes urgent the development of new antimalarial drugs. This review focuses on the antimalarial activities of 90 plant species obtained from a search using Pubmed database with keywords “antimalarials,” “plants” and “natural products.” We selected only papers published in the last 10 years (2011–2020), with a further analysis of those which were tested experimentally in malaria infected mice. Most plant species studied were from the African continent, followed by Asia and South America; their antimalarial activities were evaluated against asexual blood parasites, and only one species was evaluated for transmission blocking activity. Only a few compounds isolated from these plants were active and had their mechanisms of action delineated, thereby limiting the contribution of these medicinal plants as sources of novel antimalarial pharmacophores, which are highly necessary for the development of effective drugs. Nevertheless, the search for bioactive compounds remains as a promising strategy for the development of new antimalarials and the validation of traditional treatments against malaria. One species native in South America, Ampelozyzyphus amazonicus, and is largely used against human malaria in Brazil has a prophylactic effect, interfering with the viability of sporozoites in in vitro and in vivo experiments.

Medicinal plants as a fight against murine blood-stage malaria

OBJECTIVE

Malaria is an infectious parasitic disease affecting most of countries worldwide. Due to antimalarial drug resistance, researchers are seeking to find another safe efficient source for treatment of malaria. Since many years ago, medicinal plants were widely used for the treatment of several diseases. In general, most application is done first on experimental animals then human. In this article, medicinal plants as antimalarial agents in experimental animals were reviewed from January 2000 until November 2020.

MATERIALS AND METHODS

In this systematic review published articles were reviewed using the electronic databases NCBI, ISI Web of knowledge, ScienceDirect and Saudi digital library to check articles and theses for M.Sc/Ph.D. The name of the medicinal plant with its taxon ID and family, the used Plasmodium species, plant part used and its extract type and the country of harvest were described.

RESULTS AND CONCLUSION

The reviewed plants belonged to 83 families. Medicinal plants of families Asteraceae, Meliaceae Fabaceae and Lamiaceae are the most abundant for use in laboratory animal antimalarial studies. According to region, published articles from 33 different countries were reviewed. Most of malaria published articles are from Africa especially Nigeria and Ethiopia. Leaves were the most common plant part used for the experimental malaria research. In many regions, research using medicinal plants to eliminate parasites and as a defensive tool is popular.