Open Access Original Research Article

Aqueous Extract of Alstonia boonei Bark Reduces Chronic Hyperglycemia and Prevents its Complications through Increase of Hepatic Global Dna Methylation in Diabetic Wistar Rats

Martin Fonkoua, W. Tazon Arnold, R. Françoise Ntentié, B. Azantsa Kingue, G. Takuissu Nguemto, L. Ngondi Judith, J. Oben Enyong

European Journal of Medicinal Plants, Page 1-15
DOI: 10.9734/ejmp/2021/v32i1230431

Aim:  DNA methylation profile is involved in several physiological processes. Its alterations in the liver of diabetic patients characterized by global hypomethylation are associated with the pathophysiology of type 2 diabetes and its complications. The present study has evaluated the effect of the aqueous extract of Alstonia boonei barks on the global methylation of hepatic DNA in association with hyperglycemia and diabetes complications induced by high-fat diet (HFD) feeding and administering of streptozotocin (STZ) which mimics the metabolic abnormalities very similar to those seen in human Type 2 diabetes.

Methods: A. boonei barks were harvested, processed, dried, ground and an aqueous extraction was prepared (ratio 1/10 w/v). An in vivo study was conducted in an animal model of high-fat-streptozotocin (HF-STZ) induced diabetes. Rats were divided into five groups of five rats each: a normoglycemic group, an untreated hyperglycemic group, three hyperglycemic groups including two test groups receiving aqueous extract of A. boonei barks (AEAB) by esophageal gavage at the doses of 200 and 400 mg/kg body weight once daily and a reference group receiving metformin at 10 mg/kg body weight. After 28 days of experimentation during which fasting blood glucose levels were taken every 14 days under fasting conditions, the animals were sacrificed. Plasma and liver homogenate samples from the sacrificed rats were used for biochemical assays (markers of oxidative stress such as malondialdehyde level, superoxide dismutase (SOD) and catalase activity, and markers of lipid profile such as total cholesterol, and triglycerides, HDL-c, LDL-c and VLDL-c).  The analysis of the global DNA methylation profile was performed by the immunoprecipitation. Pearson's correlation was used to evaluate the relationship between the values.

Results: The aqueous extract increased the hepatic DNA methylation by 0.41% and 0.63% at 200 and 400 mg/kg body weight, respectively, compared to metformin (0.47%±0, 05). This effect was significantly associated with the hypoglycemic effect obtained at 400 mg/kg body weight with a decrease in initial blood glucose level of -29.87%.

Conclusion: AEAB reduces chronic hyperglycemia and prevents its complications by increasing global hepatic DNA methylation.

Open Access Original Research Article

Antifungal Activity of the Essential Oils of Osteophloeum platyspermum (Myristicaceae) against Malassezia spp. and Candida albicans Influenced by Seasonality and Climatic Factors

Jefferson S. Silva, Victoria R. Brandão, Selene D. A. Coutinho, Mateus L. B. Paciencia, Sergio A. Frana, Ingrit E. C. Díaz, Ivana B. Suffredini

European Journal of Medicinal Plants, Page 31-45
DOI: 10.9734/ejmp/2021/v32i1230433

Aims: Malassezia spp. are involved in a wide range of mammalian skin diseases. The introduction of new drugs is a need. Natural products are known to be effective in the treatment of microbial pathogens. The present study analyzed the O. platyspermum leaf essential oils (EOs) antifungal activity.

Study Design: 18 terpenes from 13 O. platyspermum leaf EOs are related to seasonal and climatic variations occurring during the dry (DS) and rainy (RS) seasons in the Amazon Rain-Forest, verified by means of multivariate analyses.

Place and Duration of the Study: the study was conducted at the Center for Research in Biodiversity (Microbiology Laboratory and Cell Culture Laboratory), Paulista University, biological activity evaluations occurred between January/2019 and December 2019).

Methodology: microdilution broth assay was used in the minimal bactericidal concentration (MBC). Multivariate analyses were used to access the relationship among MBC, seasonality and terpene composition of the EOs.

Results: Malassezia pachydermatis showed higher sensitivity to the EOs than M. furfur or C. albicans. The DS EOs were linked to the presence of limonene, myrcene, α-terpineol, linalool, terpinen-4-ol, cubenol-1-epi, influenced by insolation, temperature and evaporation, while β-elemene, γ-elemene, neo-intermedeol, elemol, α-cadinol, spathulenol, isospathulenol, viridiflorol, δ-amorphene and ledol were linked to the RS EOs, and were influenced by precipitation, relative humidity and wind velocity. DS EOs showed better antifungal activity against both Malassezia species, and the presence of the six discriminative terpenes was essential for the antifungal activity.

Conclusions: The DS EOs are a potential source of new leads to defeat animal dermatological microbes.

Open Access Original Research Article

Microwave Assisted Extraction of Berberine and Preparation of Berberine Hydrochloride from Berberis Aristata Variety of Nepal, and Quantification using RP-HPLC and HPTLC Methods

Hemanth Kumar Manikyam, Prathibha Tripathi, Jyoti Joshi, Jayaram Balasubramanian, Sandeep Balvant Patil, Trishna Lamichhane, Janardan Lamichhane

European Journal of Medicinal Plants, Page 46-53
DOI: 10.9734/ejmp/2021/v32i1230434

Berberis aristata a Himalayan woody spiny shrub with yellow flowers and red berries commonly called as Daruharidra in Sanskrit and locally in Nepal is called as Chutro or Chitra. The root and stem are the two parts widely used in traditional medicines of India and China. Berberine is the key active ingredient present in stem and root parts. Berberine hydrochloride is the derivative of berberine.  The present study aimed to study the microwave assisted extraction of berberine and its conversion into berberine hydrochloride and quantifying by RP-HPLC and HPTLC methods.In the present paper we have mentioned microwave assisted extraction of berberine and preparation of berberine hydrochloride in detail. Berberine extracted from roots of Berberis aristata using microwave assisted extraction in 80% ethanol to obtain 20% pure berberine crude by HPTLC densitometry at 350 nm absorption. The crude berberine was further purified to berberine hydrochloride by adding 10% Hcl in aqueous solution of berberine and allowed to crystallize at 5 0C over 24 hours. The crystals were further purified and recrystallized in ethanol and subjected to RP-HPLC. Reverse phase HPLC was carried out on Shimadzu UV detector at wave length of 265 nm using Acetonitrile-0.1% phosphoric acid solution (50:50) (add 0.1g sodium dodecyl sulfonate per 100ml) as the mobile phase; Phenomenex RP-column (250 mm × 4.6 mm, 5 μm), With flow rate 1.0 mL/minute, 5 µL injection volume, column temperature 25 0C for run time of 35 minutes, and retention time of berberine hydrochloride was 12.008 minutes with purity of 82%  and recovery of 90% yield obtained.

Open Access Original Research Article

Mechanistic Validation of an Ergogenic T. arjuna Standardized Extract (Oxyjun®) Using a Molecular Docking Approach

Kavita Pandey, Gursimran Kaur Uppal, Ratna Upadhyay

European Journal of Medicinal Plants, Page 54-63
DOI: 10.9734/ejmp/2021/v32i1230435

The bark of the tree Terminalia arjuna commonly referred as Arjuna is widely used in Ayurveda as a therapeutic agent for heart disease. More recently, a proprietary botanical extract of T. arjuna with tradename, Oxyjun®, demonstrated cardiotonic and ergogenic benefits for the first time in a younger and healthier population. However, the mechanism of action and biological actives of this novel sports ingredient were not clear. A molecular docking approach was adopted to understand the protein-ligand interactions and establish the most probable mechanism(s) of cardio vascular actions of the phytoconstituents of the T. arjuna standardized extract (TASE). Twenty-one phytochemicals (ligands) were chosen from Arjuna and their binding affinities against eight proteins serving cardiovascular functions (target proteins) were investigated. Autodock Vina was used to carry out the molecular docking studies. Potential efficacy in humans was assessed on the basis of ADMET properties and Lipinski’s Rule of 5. We found that arjunic acid, arjungenin, arjunetin, arjunglucoside1, chrysin, kaempferol, luteolin, rhamnetin and taxifolin demonstrated good docking scores and bioactivity.

Open Access Original Research Article

Effect of Two Drying Methods on the Bioactive Cashew Apple Varieties Consumed in the City of Garoua (Northern Cameroon)

Kouogueu Seuyim Ghislain, Nguedjo Wandji Maxwell, Dibacto Kemadjou Ruth Edwige, Nseme Mboma Yves Didier, Djouka Nembot Pelagie Marcel, Takuissu Nguemto Guy Roussel

European Journal of Medicinal Plants, Page 64-77
DOI: 10.9734/ejmp/2021/v32i1230436

Aims: The cashew tree (family Anacardiaceae) grows widely in many parts of African countries, including Cameroon. Its fruit and nut are used for food and several studies have shown their beneficial effects on health. This work aimed to evaluate the impact of two drying methods on the content of bioactive compounds and antioxidant activity.

Methodology: Four varieties (VAR 1, VAR 2, VAR 3, VAR 4) of cashew apple samples were collected and drying using sun-dried and oven-dried to a constant weight, and then ground in a blender to a powder, the fresh one was cut up and crushed in a blender. All sample were reconstituted with distilled water and polyphenols, flavonoids, alkaloids contents, and antioxidant activity through different mechanisms (DPPH radical, FRAP and TAC assays) were assessed.

Results: Alkaloids ranged from 1.50 mg EQui/g MF to 5.69 mg EQui/g DM for fresh and oven-dried VAR 1 respectively, polyphenols ranged from 786.15 mg EAG/g MF to 2836.92 mg EAG/g DM for fresh and oven-dried VAR 1 respectively, flavonoids ranged from 8.18 mg EAG/g MF to 295.45 mg EAG/g DM for fresh and oven-dried VAR 2 respectively. TAC values ranged from 13.09 mg EAA/g MF to 67.06 mg EAA/g for fresh and oven-dried VAR3 and VAR2 respectively. The highest DPPH radical scavenging value (86.25%) was obtained with fresh VAR 4 and the lowest (25.67%) with fresh VAR 1. The highest ferric reducing antioxidant power (FRAP) was obtained with fresh VAR 1 and VAR 3 (0.27 mg AAE/g MF) and the lowest with VAR 3 and VAR 4 oven-dried (0.23 mg AAE/g MF).

Conclusion: In conclusion, the different cashew varieties studied in this work are a good source of antioxidants. The drying method significantly affects bioactive compounds and antioxidant activities. A weak but not significant correlation was obtained between the number of bioactive compounds and antioxidant activities.

Open Access Original Research Article

In vitro Effects of the Methanolic Leaf Extract of Otholobium fruticans in Murine B16 Melanoma Cells: Implications for the Treatment of Skin Hyperpigmentation

Olubunmi Oyekunle, Mervin Meyer, Abram Madiehe, Ahmed Hussein, Okobi Ekpo

European Journal of Medicinal Plants, Page 94-111
DOI: 10.9734/ejmp/2021/v32i1230438

Hyperpigmentation is a cosmetically important skin disorder which commonly affects the face and neck regions and impacts negatively on the self-esteem of affected persons. Most of the current treatment agents for hyperpigmentation are cosmetic additives and prescription medications which generally act to suppress melanogenesis. However, many of these products are known to have limited effectiveness, deleterious side effects, and induce adverse reactions especially after prolonged use, hence safe and efficacious treatments are required. Herbal formulations are a putative alternative, considering their use for generations in traditional medicine for treating many diseases, including skin-related conditions. In this study, the methanolic leaf extract of Otholobium fruticans, a gardening and ornamental plant common to the South African Cape provinces, was evaluated for its possible anti-melanogenic effects based on evidence from its traditional use. The 50 µg/mL extract concentration was found to be non-toxic to murine B16 melanoma cells, to significantly reduce tyrosinase activity, increase intracellular reactive oxygen species (iROS) levels and down-regulate some melanogenesis-related genes (TYR, TRP-1, TRP-2, MITF and MC1R), except the β-catenin gene which was upregulated. These findings tend to suggest that the depigmentation potential of the methanolic extract of O. fruticans could be mediated through an interplay of mechanisms that inhibit tyrosinase activity and the cAMP-dependent pathway, as well as increased iROS levels. Further studies involving the chemical isolation, characterization and testing of the activities of the constituent compounds in O. fruticans are recommended to fully understand the basis for the current traditional uses of Otholobium plants for the treatment of skin conditions.

Open Access Original Research Article

The Importance of Monoterpenes in the Antibacterial Activity of Osteophloeum platyspermum Essential Oils

Sinária R. N. de Sousa, Jefferson de S. Silva, Mateus L. B. Paciencia, Sergio A. Frana, Ingrit E. C. Díaz, Ivana B. Suffredini

European Journal of Medicinal Plants, Page 112-121
DOI: 10.9734/ejmp/2021/v32i1230440

Aims: To evaluate antibacterial and cytotoxic activities of essential oils (EO’s) obtained from Osteophloeum platyspermum (ucuuba-chico-de-assis; Myristicaceae) fresh leaves against Staphylococcus aureus, MCF-7 breast, and PC-3 prostate cancer cell lines.

Study Design: Thirteen EO's were submitted to antibacterial and cytotoxicity assays that included 18 compounds commonly present in the EO's. The relationship between the EO's biological activities and the dry (DS) or rainy (RS) seasonal variation was accessed using the relative percentage of the terpenes.

Place and Duration of the Study: The study was conducted at the Center for Research in Biodiversity (Microbiology Laboratory and Cell Culture Laboratory), Paulista University. Biological activity assessment was conducted between October/2016 and November 2019).

Methodology: Thirteen essential oils were obtained from the leaves of O. platyspermum and were previously chemically characterized. From the analyses, 18 terpenes were determined to commonly occur in the 13 EO's. Microdilution broth and cytotoxicity assays were performed to obtain minimal bactericidal concentrations (MBCs) and 50% (EC50) effective concentrations for the cytotoxicity assays. Data from the 18 terpenes were submitted to two-way ANOVA, cluster (CA), principal component (PCA), canonical correspondence analyses (CCA), and one-sample t-test. The relationship between the biological activities of EO's and seasonal variability (dry season, DS, or rainy season, RS) was assessed. One sample t-test was performed to verify the potency of the cytotoxic effects of EO’s.

Results: Previously, 18 terpenes were identified in all the 13 EO’s. From those, α-terpineol, limonene, myrcene, linalool, and terpinen-4-ol were relevant to the ordination of the DS EO set, while spathulenol, α-pinene, β-pinene, isospathulenol, α-cadinene, ledol, cubenol-1-epi, neo-intermedeol, elemol, β-elemene, γ-elemene and viridiflorol were relevant to the ordination of the RS EO set. The biological activities were more related to the EO’s collected in the RS than those in the DS. Also, biological activities were shown to be related to the occurrence of limonene, myrcene, elemol, β-pinene, α-pinene, and terpinen-4-ol.

Conclusions: Although the presence of the 18 terpenes is necessary to maintain the species adaptability to the environment, the occurrence of limonene, myrcene, elemol, β-pinene, α-pinene, and terpinen-4-ol had a significant role in the effective expression of the biological activity of EO’s from O. platyspermum, particularly those that occur during the rainy season, in the Amazon rain forest.

Open Access Review Article

A Narrative Review of Libidibia ferrea: Botanical Aspects, Ethnopharmacological Properties, Phytochemical Characteristics, Toxicity, and Experimental Tests

Nayanne C. O. da S. Almeida, Silvania da C. Furtado, José F. M. Barcellos

European Journal of Medicinal Plants, Page 16-30
DOI: 10.9734/ejmp/2021/v32i1230432

Introduction: Jucá or pau-ferro (Libidibia ferrea) is an arboreal plant from the Fabaceae family. It is commonly used in traditional medicine in the treatment of various diseases, including inflammatory process.

Aims: The objective of this narrative review is to present botanical aspects, ethnopharmacological properties, phytochemical characteristics, toxicity highlighting, and experimental models with L. ferrea.

Results: Botanical Aspects: Jucá has several uses such as in landscaping (stem and canopy), in arborization of urban areas. Ethnopharmacological Properties: It is used in the treatment of various diseases such as diabetes, flu, asthma and, inflammatory processes of which different parts are used (root, stem bark, leaves, fruits, seeds). Phytochemical Characteristics: Phenolic compounds, fatty acids, and terpenoids are among the compounds monthly used. Toxicity: In vivo models have been used to verify toxicity and in most studies the plant presented no toxicity in its use. Experimental studies: Animals, such as mice, dogs, rats, etc. and different models of studies to analyze the action of the plant were used.

Conclusions: Such low toxicity, associated with its widespread use in folk medicine and its various effects demonstrated in the studies included in this Review have corroborated for the continuity of the research with L. ferrea. New studies, however, ought to follow methodological guidelines, such as the Animal Research: reporting in vivo Experiments (ARRIVE) so that, a methodological design secures more homogeneous studies capable of quantifying the actual size of the effect in the plant may have in clinical studies.


Open Access Review Article

Bioactive Building Blocks and Potential Pharmacological Perspectives of Green Coffee: A Review

Namrata Kundu, Gaurav Pant

European Journal of Medicinal Plants, Page 78-93
DOI: 10.9734/ejmp/2021/v32i1230437

Coffee is known to be one of the popular beverages today on the globe. Due to its easy availability and preparation, it is consumed by the population of almost all countries. This wonder crop was discovered in the 6th century in Ethiopia. Since then, people have also used various brewing methods to extract hundreds of the bioactive compounds present in these aromatic seeds. No doubt, excessive consumption of the same can be harmful too. As a functional food, coffee is known to have multiple health benefits. Coffee beans contain vitamins, minerals, caffeine, chlorogenic acid, and various other biologically active ingredients. This review briefly describes the major biologically active compounds present in these seeds – caffeine, trigonelline, diterpenes, and chlorogenic acid (CGA). It also aims to describe various bioactive activities such as antioxidant, antiproliferative, antibacterial, antiviral, etc., against variable hallmarks. Thus, explaining different pharmacological effects for the welfare of the human population.