METHODS: The fresh Azolla pinnata plant from Kuala Krai, Kelantan, Malaysia was used for crude extraction using Soxhlet and maceration methods. Then, the chemical composition of extracts and its structure were identified using GCMS-QP2010 Ultra (Shimadzu). Next, following the WHO procedures for larval bioassays, the extracts were used to evaluate the early 4th instar larvae of Aedes mosquito vectors.
RESULTS: The larvicidal activity of Azolla pinnata plant extracts evidently affected the early 4th instar larvae of Aedes aegypti mosquito vectors. The Soxhlet extraction method had the highest larvicidal effect against Ae. aegypti early 4th instar larvae, with LC50 and LC95 values of 1093 and 1343 mg/L, respectively. Meanwhile, the maceration extraction compounds were recorded with the LC50 and LC95 values of 1280 and 1520 mg/L, respectively. The larvae bioassay test for Ae. albopictus showed closely similar values in its Soxhlet extraction, with LC50 and LC95 values of 1035 and 1524 mg/L, compared with the maceration extraction LC50 and LC95 values of 1037 and 1579 mg/L, respectively. The non-target organism test on guppy fish, Poecilia reticulata, showed no mortalities and posed no toxic effects. The chemical composition of the Azolla pinnata plant extract has been found and characterized as having 18 active compounds for the Soxhlet method and 15 active compounds for the maceration method.
CONCLUSIONS: Our findings showed that the crude extract of A. pinnata bioactive molecules are effective and have the potential to be developed as biolarvicides for Aedes mosquito vector control. This study recommends future research on the use of active ingredients isolated from A. pinnata extracts and their evaluation against larvicidal activity of Aedes in small-scale field trials for environmentally safe botanical insecticide invention.
METHODS: Growth inhibitory indices and fractional inhibitory concentration index were applied to evaluate the in vitro synergistic activity of phytoextract-antibiotic combinations in general.
FINDINGS: A number of studies have indicated that plant-derived natural compounds are capable of significantly reducing the minimum inhibitory concentration of standard antibiotics by altering drug-resistance mechanisms of B. anthracis and other superbug infection causing bacteria. Phytochemical compounds allicin, oleanolic acid, epigallocatechin gallate and curcumin and Jatropha curcas extracts were exceptional synergistic potentiators of various standard antibiotics.
CONCLUSION: Considering these facts, phytochemicals represents a valuable and novel source of bioactive compounds with potent antibiotic synergism to modulate bacterial drug-resistance.
METHODS: This study evaluated the functional constituents, antioxidant and anti-inflammatory activities of Malaysian Ganoderma lucidum aqueous extract (GLE) and Egyptian Chlorella vulgaris ethanolic extract (CVE). Also, the synergistic, addictive or antagonistic activities of the combination between the two extracts (GLE-CVE) were studied. Expression of inducible nitric oxide synthase, cyclooxygenase-2, and nuclear factor-kappa B, as well as levels of nitric oxide, tumor necrosis factor (TNF)-α, lipid peroxidation, reduced glutathione and antioxidant enzymes were determined using in vitro model of lipopolysaccharide-stimulated white blood cells.
OBJECTIVE: This study investigates the antidiabetic and antioxidant effects of M. latifolia bark extracts, fractions, and isolated constituents.
MATERIALS AND METHODS: Melicope latifolia extracts (hexane, chloroform, and methanol), fractions, and isolated constituents with varying concentrations (0.078-10 mg/mL) were subjected to in vitro α-amylase and dipeptidyl peptidase-4 (DPP-4) inhibitory assay. Molecular docking was performed to study the binding mechanism of active compounds towards α-amylase and DPP-4 enzymes. The antioxidant activity of M. latifolia fractions and compounds were determined by 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging and β-carotene bleaching assays.
RESULTS: Melicope latifolia chloroform extract showed the highest antidiabetic activity (α-amylase IC50: 1464.32 μg/mL; DPP-4 IC50: 221.58 μg/mL). Fractionation of chloroform extract yielded four major fractions (CF1-CF4) whereby CF3 showed the highest antidiabetic activity (α-amylase IC50: 397.68 μg/mL; DPP-4 IC50: 37.16 μg/mL) and resulted in β-sitosterol (1), halfordin (2), methyl p-coumarate (3), and protocatechuic acid (4). Isolation of compounds 2-4 from the species and their DPP-4 inhibitory were reported for the first time. Compound 2 showed the highest α-amylase (IC50: 197.53 μM) and β-carotene (88.48%) inhibition, and formed the highest number of molecular interactions with critical amino acid residues of α-amylase. The highest DPP-4 inhibition was exhibited by compound 3 (IC50: 911.44 μM).
DISCUSSION AND CONCLUSIONS: The in vitro and in silico analyses indicated the potential of M. latifolia as an alternative source of α-amylase and DPP-4 inhibitors. Further pharmacological studies on the compounds are recommended.
AIM OF THIS REVIEW: The present study is a critical assessment of the state-of-the-art concerning the traditional uses, the phytochemistry and the pharmacology of species belonging to the genus Hedyosmum to suggest further research strategies and to facilitate the exploitation of the therapeutic potential of Hedyosmum species for the treatment of human disorders.
MATERIALS AND METHODS: The present review consists of a systematic overview of scientific literature concerning the genus Hedyosmum published between 1965 and 2018. Moreover, an older text, dated from 1843, concerning the traditional uses of H. bonplandianum Kunth has also been considered. Several databases (Francis & Taylor, Google Scholar, PubMed, SciELO, SciFinder, Springer, Wiley, and The Plant List Database) have been used to perform this work.
RESULTS: Sixteen species of the genus Hedyosmum have been mentioned as traditional remedies, and a large number of ethnomedicinal uses, including for the treatment of pain, depression, migraine, stomach-ache and ovary diseases, have been reported. Five species have been used as flavouring agents, tea substitutes or foods. Sesterterpenes, sesquiterpene lactones, monoterpenes, hydroxycinnamic acid derivatives, flavonoids, and neolignans have been reported as the most important compounds in these species. Studies concerning their biological activities have shown that members of the Hedyosmum genus possesses promising biological properties, such as analgesic, antinociceptive, antidepressant, anxiolytic, sedative, and hypnotic effects. Preliminary studies concerning the antibacterial, antioxidant, antiplasmodial, and antifungal activities of these plants as well as their cytotoxic activities against different tumour cell lines have been reported. Some active compounds from the Hedyosmum genus have been used as starting points for the innovative and bioinspired development of synthetic molecules. A critical assessment of these papers has been performed, and some conceptual and methodological problems have been identified regarding the materials and methods and the experimental design used in these studies, including a lack of ethnopharmacological research.
CONCLUSIONS: The present review partially confirms the basis for some of the traditional uses of Hedyosmum species (mainly H. brasiliense) through preclinical studies that demonstrated their antinociceptive and neuroprotective effects. Due to promising preliminary results, further studies should be conducted on 13-hydroxy-8,9-dehydroshizukanolide and podoandin. Moreover, several essential oils (EOs) from this genus have been preliminarily investigated, and the cytotoxic and antibacterial activities of H. brasiliense and H. sprucei EOs certainly deserve further investigation. From the promising findings of the present analysis, we can affirm that this genus deserves further research from ethnopharmacological and toxicological perspectives.