Studies on the Volatile Oils ofMomordica charantiaL. (Cucurbitaceae) andPhyllanthus amarusSch. et Thonn (Euphorbiaceae)

Determination of the volatile chemical profile of Momordica charantia (bitter melon) leaf and fruit by GC-MS

The plant Momordica charantia (Cucurbitaceae), popularly known as bitter melon, snake fruit, Saint Vincent's herb, or little melon, is an African species that has developed in tropical and subtropical biomes in various parts of Brazil. The fruit is used in various traditional medicinal applications. The study aimed to identify the compounds of the essential oil of the leaves obtained by hydrodistillation and in the fruit through Solid-Phase Microextraction by headspace mode (HS-SPME) coupled to gas chromatography-mass spectrometry (GC-MS). The analysis of mature fruits led to the identification of 18 compounds, compared to the hydrodistillation, in which 21 compounds were identified. Benzaldehyde, linalool, and β-cyclocitral were identified in both methods. Linalool was the major compound in both processes. These findings highlight the importance of knowing the chemical composition of organic volatile compounds (VOCs), given the potential for medicinal applications and popular use of plants.

An insight into the potent medicinal plant Phyllanthus amarus Schum. and Thonn

Phyllanthus amarus Schum. and Thonn., a globally distributed herb is known for its several therapeutic potentials. P. amarus has a long history of use in the traditional system of medicine for over 2000 years owing to its wide array of secondary metabolites that confer significant medicinal attributes. Research on various aspects including ethnobotany, phytochemistry to bioactivity, or pharmacological studies has been conducted over the past several decades on this potent herb. P. amarus extracts have shown a broad range of pharmacological activities like hepatoprotective, antioxidant, antiviral, antimicrobial, antidiabetic, anti-inflammatory, anticancer, antimalarial, nephroprotective, diuretic, and several other properties. The present review compiles and covers literature and research of several groups across past decades to date and focuses on how the therapeutic significance of this plant can be further explored for future research either as herbal formulations, alternative medicine, or in the pharmaceutical industry.

Supplementary Information

The online version contains supplementary material available at 10.1007/s13237-022-00409-z.

Identification of Volatiles of the Dinoflagellate Prorocentrum cordatum

The dinoflagellate Prorocentrum cordatum, often called P. minimum, is a potentially toxic alga found in algal blooms. Volatile compounds released by the alga might carry important information, e.g., on its physiological state, and may act as chemical messengers. We report here the identification of volatile organic compounds emitted by two strains, xenic P. cordatum CCMP 1529 and axenic P. cordatum CCMP 1329. The volatiles released during culture were identified despite their low production rates, using sensitive methods such as open-system-stripping analysis (OSSA) on Tenax TA desorption tubes, thermodesorption, cryofocusing and GC/MS-analysis. The analyses revealed 16 compounds released from the xenic strain and 52 compounds from the axenic strain. The majority of compounds were apocarotenoids, aromatic compounds and small oxylipins, but new natural products such as 3,7-dimethyl-4-octanolide were also identified and synthesized. The large difference of compound composition between xenic and axenic algae will be discussed.

A simple "turn-on" fluorescence sensor for salicylaldehyde skeleton based on switch of PET-AIE effect

The selective detection of salicylaldehyde skeleton is of great significance in phytochemistry and biological research but rarely reported. In this research, a simple and highly selective "turn-on" fluorescence sensor (CDB-Am) for salicylaldehyde skeleton was developed based on switch of photoinduced electron transfer (PET) and aggregation-induced emission (AIE). CDB-Am bearing amino-cyanodistyrene structure responded to salicylaldehyde in the range of 3.1 to 40 μM with a detection limit of 0.94 μM. The sensing process of formation of Schiff-base adduct CDB-SA was confirmed by ¹H NMR, MS, and FT-IR spectra, revealing that a recovered AIE property accounted for the turn-on fluorescence response of CDB-Am and the intramolecular hydrogen bonding played a crucial role in the disruption of PET process. This sensing ability was successfully applied for both fluorescence qualitative test of salicylaldehyde skeleton on TLC analysis and quantitative detection of salicylaldehyde skeleton with good accuracy in the root bark of Periploca sepium, suggesting the extensive applications in phytochemistry and traditional Chinese herbal medicine. Furthermore, CDB-Am exhibited the first excellent fluorescence imaging ability in detecting salicylaldehyde skeleton in a living system. This work supplied a new strategy of preparing a novel "turn-on" fluorescence probe for detecting salicylaldehyde skeleton in complex environments and living bodies.

Chemical Constituents, Anti-nociceptive and Anti-inflammatory Activities of Essential Oil of Phyllanthus muellerianus

The aim of the present study was to characterize the chemical composition and to evaluate the anti-inflammatory and anti-nociceptive properties of the essential oil from the leaves of Phyllanthus muellerianus (Kuntze) Exell. The essential oil was hydrodistilled and characterized by gas chromatography-flame ionization detection and gas chromatography coupled with mass spectrometry analyses. The anti-inflammatory activity was evaluated on carrageenan-induced rat paw edema while the anti-nociceptive test was based on hot plate analysis. The hydrodistillation afforded 0.09% (dry weight basis) of pale yellow oil. Thirty-eight compounds representing 94.8% were identified in the oil. The major components of the oil were hexahydrofarnesyl acetone (11.6%), isocaryophyllene (9.8%), and limonene (9.4%). The oils of P. muellerianus displayed anti-nociceptive effect at a rate independent of reaction time and dose ( P < 0.001). The rate of inhibition increased exponentially as the dose increases with optimum activity at 400 mg/kg. The carrageenan-induced edema model revealed the suppression of inflammatory mediators at a very high significant value ( P < 0.001) for all doses, showing activity comparable to a standard drug at 4 hours after carrageenan injection. Collectively, the essential oils depressed the nociceptors and most likely acted as centrally mediated opioid analgesics while the anti-inflammatory mechanisms of the oil might be related to the decrease in the level of iNOS, and cyclo-oxygenase-2 in the edema paw via the suppression of pro-inflammatory cytokines (TNF-α, IL1-β), NO, and PGE2 production. This study confirms the analgesics and inflammatory activities of P. muellerianus.

Anti-inflammatory effects of Phyllanthus amarus Schum. & Thonn. through inhibition of NF-κB, MAPK, and PI3K-Akt signaling pathways in LPS-induced human macrophages

Background

Phyllanthus amarus has been used widely in various traditional medicines to treat swelling, sores, jaundice, inflammatory diseases, kidney disorders, diabetes and viral hepatitis, while its pharmacological and biochemical mechanisms underlying its anti-inflammatory properties have not been well investigated. The present study was carried out to investigate the effects of 80% ethanolic extract of P. amarus on pro-inflammatory mediators release in nuclear factor-kappa B (NF-кB), mitogen activated protein kinase (MAPK) and phosphatidylinositol 3-kinase/Akt (PI3K-Akt) signaling activation in lipopolysaccharide (LPS)-induced U937 human macrophages.

Methods

The release of prostaglandin E₂ (PGE₂) and pro-inflammatory cytokines, tumor necrosis factor (TNF)-α and interleukin (IL)-1β in a culture supernatant was determined by ELISA. Determination of cyclooxygenase-2 (COX-2) protein and the activation of MAPKs molecules (JNK, ERK and p38 MAPK), NF-κB and Akt in LPS-induced U937 human macrophages were investigated by immunoblot technique. The relative gene expression levels of COX-2 and pro-inflammatory cytokines were measured by using qRT-PCR. The major metabolites of P. amarus were qualitatively and quantitatively analyzed in the extract by using validated reversed-phase high performance liquid chromatography (HPLC) methods.

Results

P. amarus extract significantly inhibited the production of pro-inflammatory mediators (TNF-α, IL-1β, PGE₂) and COX-2 protein expression in LPS-induced U937 human macrophages. P. amarus-pretreatment also significantly downregulated the increased mRNA transcription of pro-inflammatory markers (TNF-α, IL-1β, and COX-2) in respective LPS-induced U937 macrophages. It downregulated the phosphorylation of NF-κB (p65), IκBα, and IKKα/β and restored the degradation of IκBα, and attenuated the expression of Akt, JNK, ERK, and p38 MAPKs phosphorylation in a dose-dependent manner. P. amarus extract also downregulated the expression of upstream signaling molecules, TLR4 and MyD88, which play major role in activation of NF-κB, MAPK and PI3K-Akt signaling pathways. The quantitative amounts of lignans, phyllanthin, hypophyllahtin and niranthin, and polyphenols, gallic acid, geraniin, corilagin, and ellagic acid in the extract were determined by HPLC analysis.

Conclusion

The study revealed that P. amarus targeted the NF-κB, MAPK and PI3K-Akt signaling pathways to exert its anti- inflammatory effects by downregulating the prospective inflammatory signaling mediators.

Electronic supplementary material

The online version of this article (10.1186/s12906-018-2289-3) contains supplementary material, which is available to authorized users.

Composition and Antimicrobial Activity of the Essential Oils of Three Plant Species from the Sabana of Bogota (Colombia): Myrcianthes leucoxyla, Vallea stipularis and Phyllanthus salviifolius

In recent decades, essential oils (EOs) have become an important alternative source of antimicrobial agents. The objective of this study was to evaluate the antimicrobial activity of EOs obtained from the leaves of Myrcianthes leucoxyla Mc. Vaughn., Vallea stipularis L.f and Phyllanthus salviifolius Kunth for prevalent microbial strains and also to contribute to the knowledge of their chemical composition. EOs were obtained by hydrodistillation and analyzed by GC-MS. The main compounds for V. stipularis EO were α-tujene (6.6%) and cedrene epoxide (12.0%), for M. leucoxila EO 1,8 cineole (6.3%) and caryophyllene oxide (21.7%), and for P. salviifolius aristolene (17.3%) and geranyl tiglate (15.9%). Antimicrobial tests showed that M. leucoxyla EO was the most active, showing zones of inhibition against all strains used, specifically against Pseudomonas aeruginosa and Salmonella typhimurium with percentages of inhibition higher than 50%. Compared with positive controls, this activity may be related to the presence of 1,8 cineole.

An overview of important ethnomedicinal herbs of Phyllanthus species: present status and future prospects

The genus Phyllanthus consists of more than 1000 species, of which many are used as traditional medicines. The plant extracts have been used since ancient times, for treating hypertension, diabetes, hepatic, urinary, and sexual disorders, and other common ailments. Modern day scientific investigations have now confirmed pharmacognostic properties of Phyllanthus herbs. The phytochemicals attributing these medicinal properties have been identified in many of the Phyllanthus herbs. The morphologically similar herbs of Phyllanthus grow together and admixture of species during collection for manufacture of herbal medicines is quite common. Hence, along with pharmacognostic and phytochemical studies, appropriate protocols for correct identification of species are also important. As the use of these herbs as green medicines is becoming more popular, it is imperative to assess its genetic diversity and phylogenetic relatedness for future conservation strategies. This review is an attempt to present an overview of the existing studies on pharmacognostics, phytochemistry, species identification, and genetic diversity of Phyllanthus herbs and consequently (i) highlight areas where further research is needed and (ii) draw attention towards extending similar studies in underutilized but potentially important herbs such as P. maderaspatensis, P. kozhikodianus, P. rheedii, P. scabrifolius, and P. rotundifolius.

GC and GC-MS analysis of the essential oil of Nepeta cilicica Boiss. ex Benth. from Lebanon

The hydrodistillation of the aerial parts of Nepeta cilicica Boiss. ex Benth., collected in Lebanon in the Horsh Ehden reserve, yielded 0.13% (w/w) of essential oil. Gas chromatography (GC) and GC-mass spectroscopy analysis enabled the identification of 75 compounds representing 96.8% of the total oil. The most abundant compounds were spathulenol (15.1%), hexadecanoic acid (14%), δ-cadinene (5.5%) and α-copaene (4.5%). On the whole, the oil was constituted mainly by sesquiterpenes (45.9%), among which sesquiterpene hydrocarbons (27.6%) slightly prevailed over oxygenated sesquiterpenes (18.3%).

Phyllanthus amarus: ethnomedicinal uses, phytochemistry and pharmacology: a review

ETHNOPHARMACOLOGICAL RELEVANCE

Phyllanthus amarus Schum. & Thonn. belongs to the family Euphorbiaceae is a small herb well known for its medicinal properties and widely used worldwide. P. amarus is an important plant of Indian Ayurvedic system of medicine which is used in the problems of stomach, genitourinary system, liver, kidney and spleen. It is bitter, astringent, stomachic, diuretic, febrifuge and antiseptic. The whole plant is used in gonorrhea, menorrhagia and other genital affections. It is useful in gastropathy, diarrhoea, dysentery, intermittent fevers, ophthalmopathy, scabies, ulcers and wounds.

MATERIALS AND METHODS

The present review covers a literature across from 1980 to 2011. Some information collected from traditional Ayurvedic texts and published literature on ethanomedicinal uses of Phyllanthus amarus in different countries worldwide.

RESULTS

Phytochemical studies have shown the presence of many valuable compounds such as lignans, flavonoids, hydrolysable tannins (ellagitannins), polyphenols, triterpenes, sterols and alkaloids. The extracts and the compounds isolated from P. amarus show a wide spectrum of pharmacological activities including antiviral, antibacterial, antiplasmodial, anti-inflammatory, antimalarial, antimicrobial, anticancer, antidiabetic, hypolipidemic, antioxidant, hepatoprotective nephroprotective and diurectic properties.

CONCLUSION

The present review summarizes information concerning the morphology, ecology, ethnopharmacology, phytochemistry, biological activities, clinical applications and toxicological reports of P. amarus. This review aims at gathering the research work undertaken till date on this plant in order to provide sufficient baseline information for future works and commercial exploitation.