Microscopic Features, Mineral Contents, Anti-sickling, Antioxidant and Antibacterial Activities of Stem Bark of Harungana madagascariensis Lam. Ex Poiret (Hypericaceae)

Abstract

Aims: This study addressed the identification of bioactive compounds, the determination of mineral content and the evaluation of the antibacterial, antioxidant and anti-sickling activities of aqueous extract from stem bark of Harungana madagascariensis. 
 Place and Duration of Study: Centre d’Etudes des Substances Naturelles d’Origine Végétale (CESNOV), Faculty of Pharmaceutical Sciences, University of Kinshasa and Faculty of Sciences, National Pedagogic University in DRC, between October 2018 and January 2021.
 Methodology: Phytochemical screening was evaluated by chromatographic methods (TLC and HPLC), the mineral composition by ICP-AES and the antioxidant activities using ABTS and DPPH assays, the antibacterial activity against four bacteria strains using the micro-dilution method; and the in vitro anti-sickling activity by the Emmel test.
 Results: Phytochemical analysis revealed the abundance in this plant of phytochemicals such as alkaloids, flavonoids, tannins, anthraquinones and triterpenoids. The extract contains sodium, iron, selenium and zinc in proportions of 955.40 ppm, 369.65 ppm, 375.70 ppm and 44.79 ppm respectively as well as copper, chromium and other elements. The antioxidant potential of the stem bark infusion extract from H. madagascariensis, evaluated by the ABTS and DPPH tests, showed very high antioxidant activity due to this free radical scavenging capacity linked to IC50 values of 3.08 ± 0.19 µg/mL (ABTS) and 3.53 ± 0.22 µg/mL (DPPH). The antibacterial sensitivity testing with MIC determination performed on a strain isolated from a sickle cell patient and four reference strains showed the MIC values of the extract ranged from 31.25 µg/mL to 250 µg/mL. The lowest MIC value was observed on S. aureus ATCC 25923 while the highest MIC value was obtained on Enterococcus spp Clinical.
 Conclusion: The stem bark extract of H. madagascariensis showed high anti-sickling activity at 10.42 µg/mL, which may be due to its phytochemical constituents such as saponins, alkaloids and flavonoids Obtained results could justify the efficacy of recipes from stem bark of Harungana madagascariensis in the management of various infections in traditional medicine and anti-sickle cell disease.

Phytochemical investigation and antisickling properties of a Poly-herbal formula on the HBSS Red Blood Cells

“…In addition to these works, the results of investigations by (Fatokun et al, 2015; Mukeba et al, 2020) [30,31] on the antisickling activity of some Congolese and Nigerian medicinal plants respectively showed that aqueous and ethanolic extracts of H. madagascariensis inhibited HbS polymerization by 42% and reversed sickle cells by 52%. In addition, results from previous work (Tatiana et al, 2020) [32] showed that aqueous and ethanolic extracts of Z. leprieurii inhibited sickle cell formation by 89% and 81% respectively.…”

“…These authors reported that the inhibition of falciformation generated by this extract was due to the presence of amino acids such as phenylalanine glutamic acid, arginine, Tyrosine and aspartic acid in varying concentrations. In addition, authors such as ( [28,29,30] claim that aromatic amino acids have antisickling activity. The presence of these amino acids in our plant extracts could participate in the fight against sickle cell disease by having a polymerization inhibition activity.…”

Micromorphological evaluation of Daphne mucronata Royle and Myrtus communis L. using scanning electron microscopic techniques

“…Vessels are involved in the transport system of the plant. Mukeba et al (2020) found similar calcium oxalate prisms in the stem bark powder of H. madagascariensis and stated that these are helpful in the detection of adulterants and in identification of herbal drugs. Parenchyma cells constitute the ground tissue, sclerenchyma cells give support to plant body and trichomes play a key role in sustaining water balance, reflect radiations, lower the plant temperature, and prevent water loss in the plants (Ishtiaq et al, 2018).…”

Ethnobotanical, Phytochemical and Pharmacological Studies of Capsicum annuum L. (Solanaceae) in the Healing of Traumatic Wounds (Case of Eye Wounds): A Mini Review

“…In developing countries where the population lives below $0.20/person/day [48,49]. The population practices self-medication by using certain non-steroidal anti-inflammatory eye drops in order to reduce or relieve pain).…”