Evaluation of the Antioxidant, Hepatoprotective, and Anti-Inflammatory Activities of Bisresorcinol Isolated from the Trunk of Heliciopsis Terminalis

Glycoside constituents from Cayratia geniculata

Using various chromatographic separations, six glycoside derivatives (1-6), including one new ent-labdane glucoside named cayratioside (1), were isolated from the methanol extract of Cayratia geniculata stems and leaves. Their structures were elucidated by detailed analysis of the 1D, 2D NMR, and HRESIQTOF mass spectra. The inhibitory effect of 1-6 on LPS-induced NO production in RAW264.7 cells was also evaluated. Among isolated compounds, 1 exhibited moderate activity with an IC50 value of 59.65 ± 1.85 µM.

In vivo hepatoprotective and nephroprotective effects of Stenocarpus sinuatus leaf extract against ifosfamide-induced toxicity in rats

Ifosfamide (IFOS) is a broad-spectrum chemotherapeutic agent that has been extensively used for breast cancer and other solid tumors. Unfortunately, its use is associated with toxicities of several organs. Stenocarpus sinuatus is an Australian tree belonging to the Proteaceae family. In the current study, the phytochemical constituents of S. sinuatus methanol leaf extract (SSLE) were assessed. In addition, the protective effect of SSLE against IFOS-induced nephrotoxicity and hepatotoxicity was evaluated. Rats were randomly divided into six groups: control, IFOS (50 mg/kg), IFOS + SSLE (100 mg/kg), IFOS + SSLE (200 mg/kg), IFOS + SSLE (400 mg/kg), and SSLE (400 mg/kg). Hepatoprotective and nephroprotective potency of SSLE was assessed using different biochemical parameters. The phytochemical investigation resulted in the isolation of four flavonoid glycosides (kaempferol 3-O-β- d-glucopyranosyl-(1→2)-α- l-rhamnopyranoside, kaempferol 3-O-α-rhamnopyranoside, isorhamnetin 3-O-β- d-glucopyranosyl-(1→2)-α- l-rhamnopyranoside, and quercetin 3-O-β- d-glucopyranosyl-(1→2)-α- l-rhamnopyranoside) and a coumarin (scopoletin). This is the first report on the isolated compounds from the genus Stenocarpus. SSLE showed enhancement of kidney and liver functions and reduction of oxidative stress and inflammation. The histopathology of the investigated organs confirmed the protective effect of SSLE. In conclusion, SSLE is considered as a promising candidate that can be used in defense against the toxic effects of IFOS after further clinical trials.

Assessment of antimalarial activity of crude extract of Chan-Ta-Lee-La and Pra-Sa-Chan-Dang formulations and their plant ingredients for new drug candidates of malaria treatment: In vitro and in vivo experiments

The emergence and spread of antimalarial drug resistance have become a significant problem worldwide. The search for natural products to develop novel antimalarial drugs is challenging. Therefore, this study aimed to assess the antimalarial and toxicological effects of Chan-Ta-Lee-La (CTLL) and Pra-Sa-Chan-Dang (PSCD) formulations and their plant ingredients. The crude extracts of CTLL and PSCD formulations and their plant ingredients were evaluated for in vitro antimalarial activity using Plasmodium lactate dehydrogenase enzyme and toxicity to Vero and HepG2 cells using the tetrazolium salt method. An extract from the CTLL and PSCD formulations exhibiting the highest selectivity index value was selected for further investigation using Peter's 4-day suppressive test, curative test, prophylactic test, and acute oral toxicity in mice. The phytochemical constituents were characterized using gas chromatography-mass spectrometry (GC-MS). Results showed that ethanolic extracts of CTLL and PSCD formulations possessed high antimalarial activity (half maximal inhibitory concentration = 4.88, and 4.19 g/mL, respectively) with low cytotoxicity. Ethanolic extracts of the CTLL and PSCD formulations demonstrated a significant dose-dependent decrease in parasitemia in mice. The ethanolic CTLL extract showed the greatest suppressive effect after 4 days of suppressive (89.80%) and curative (35.94%) testing at a dose of 600 mg/kg. Moreover, ethanolic PSCD extract showed the highest suppressive effect in the prophylactic test (65.82%) at a dose of 600 mg/kg. There was no acute toxicity in mice treated with ethanolic CTLL and PSCD extracts at 2,000 mg/kg bodyweight. GC-MS analysis revealed that the most abundant compounds in the ethanolic CTLL extract were linderol, isoborneol, eudesmol, linoleic acid, and oleic acid, whereas ethyl 4-methoxycinnamate was the most commonly found compound in the ethanolic PSCD extract, followed by 3-hydroxy-2-(4-hydroxy-3-methoxyphenyl)-4H-chromen-4-one, flamenol, oleic acid amide, linoleic acid, and oleic acid. In conclusions, ethanolic CTLL and PSCD extracts exhibited high antimalarial efficacy in vitro. The ethanolic CTLL extract at a dose of 600 mg/kg exhibited the highest antimalarial activity in the 4-day suppressive and curative tests, whereas the ethanolic PSCD extract at a dose of 600 mg/kg showed the highest antimalarial activity in the prophylactic test.

Acylated flavonoid glycosides from Barringtonia pendula and their inhibition on lipopolysaccharide-induced nitric oxide production in RAW264.7 cells

Six new acylated flavonoid glycosides namely barringosides J - O (1-6) along with tephrokaempferoside and barringoside D were isolated from the branches and leaves of Barringtonia pendula. The structural elucidation was confirmed by extensive analysis of their spectroscopic data including HRQTOFMS, 1D and 2D NMR experiments. Moderate inhibitory effects on LPS-induced NO production in RAW264.7 cells were observed for barringosides M (4) and N (5) with IC50 values of 48.40 ± 3.01 and 56.61 ± 3.87 μM, whereas weak inhibition was found for compounds 1-3, 6, and 7 with IC50 values ranging from 64.91 ± 3.68 to 79.80 ± 3.90 μM.

A Review of Phytochemicals and Bioactive Properties in the Proteaceae Family: A Promising Source of Functional Food

In recent decades, natural plant-based foods have been increasingly used to improve human health due to unhealthy modern dietary patterns, such as the consumption of foods high in sugar and fat. Many indigenous species have been used by Aboriginal peoples for their food and therapeutic properties. Thus, it is important to understand the health-enhancing bioactive profile of Australian indigenous species. The Proteaceae family, such as the genera of Protea, Macadamia, and Grevillea, have been commercially used in the horticulture and food industries. Researchers have reported some findings about Persoonia species, one of the genera in the Proteaceae family. The aim of this review was to provide an overview of the family Proteaceae and the genus Persoonia, including distribution, traditional and commercial uses, phytochemicals, bioactive properties, potential opportunities, and challenges. In this review, bioactive compounds and their properties related to the health benefits of the Proteaceae family, particularly the Persoonia genus, were reviewed for potential applications in the food industry.

Heliciopsides A-E, Unusual Macrocyclic and Phenolic Glycosides from the Leaves of Heliciopsis terminalis and Their Stimulation of Glucose Uptake

Ten phenolic constituents, including three new macrocyclic glycosides (1-3), a new phenolic glycoside (5), a new biphenyl glycoside (6), and five known compounds (4, 7-10), were isolated from a 70% MeOH extract of the leaves of Heliciopsis terminalis by liquid chromatography-tandem mass spectrometry (LC-MS/MS)-guided molecular networking. The chemical structures of new compounds 1-3, 5 and 6 were established based on comprehensive spectroscopic data analysis, including 1D and 2D NMR and HRESIMS techniques. All isolated compounds (1-10) were evaluated for their stimulation of glucose uptake in differentiated 3T3-L1 adipocytes using 2-deoxy-2-[(7-nitro-2,1,3-benzoxadiazol-4-yl)amino]-d-glucose (2-NBDG) as a fluorescent glucose analog. Compounds 3, 6 and 8 showed stimulatory effects on the uptake of 2-NBDG in 3T3-L1 adipocyte cells. Among them, compounds 3 and 6 activated the AMPK signaling pathway in differentiated C2C12 myoblasts.

Lignans and Other Compounds From the Roots of Pandanus tonkinensis and Their Lipid Peroxidation Inhibitory Activity

A new phenylpropane (1) and 9 known (2-10) compounds were isolated from the methanol extract of Pandanus tonkinensis roots. Their chemical structures were determined as (7 S)-2,6-dimethoxyphenyl-7,9-propanediol-1 -O-β-D-glucopyranoside (1), isorhapontigenin (2), pinoresinol-4,4′-di -O-β-D-glucoside (3), isoeucommin A (4), pinoresinol-4′ -O-β-D-glucoside (5), acanthoside B (6), eucommin A (7), urolignoside (8), benzyl O-α-L-arabinopyranosyl-(1→6) -β-D-glucopyranoside (9), and (6 S,9 S)-roseoside (10) by comprehensive analysis of high-resolution electron spray ionization mass spectrum and nuclear magnetic resonance spectral data, as well as by comparison of their spectral data with those reported in the literature. In addition, the stereochemistry of 1 was successfully determined by both theoretical and calculated CD spectra. All the isolates were tested for their lipid peroxidation inhibitory effects by in vitro assay. Compounds 2-7 exhibited significantly lipid peroxidation inhibitory effects with IC50 values of 21.3 ± 1.7, 61.9 ± 3.9, 57.5 ± 5.5, 10.4 ± 0.7, 28.9 ± 0.3, 54.2 ± 3.5 µM, respectively, compared to that of the positive control, trolox (31.4 ± 2.2 µM).

GC/MS Profiling, Anti-Collagenase, Anti-Elastase, Anti-Tyrosinase and Anti-Hyaluronidase Activities of a Stenocarpus sinuatus Leaves Extract

Today, skin care products and cosmetic preparations containing natural ingredients are widely preferred by consumers. Therefore, many cosmetic brands are encouraged to offer more natural products to the market, such as plant extracts that can be used for their antiaging, antiwrinkle, and depigmentation properties and other cosmetic purposes. In the current study, the volatile constituents of the hexane-soluble fraction of a Stenocarpus sinuatus (family Proteaceae) leaf methanol extract (SSHF) were analyzed using GC/MS analysis. Moreover, the antiaging activity of SSHF was evaluated through in vitro studies of anti-collagenase, anti-elastase, anti-tyrosinase, and anti-hyaluronidase activities. In addition, an in silico docking study was carried out to identify the interaction mechanisms of the major compounds in SSHF with the active sites of the target enzymes. Furthermore, an in silico toxicity study of the identified compounds in SSHF was performed. It was revealed that vitamin E (α-tocopherol) was the major constituent of SSHF, representing 52.59% of the extract, followed by γ-sitosterol (8.65%), neophytadiene (8.19%), β-tocopherol (6.07%), and others. The in vitro studies showed a significant inhibition by SSHF of collagenase, elastase, tyrosinase, and hyaluronidase, with IC₅₀ values of 60.03, 177.5, 67.5, and 38.8 µg/mL, respectively, comparable to those of the positive controls epigallocatechin gallate (ECGC, for collagenase, elastase, hyaluronidase) and kojic acid (for tyrosinase). Additionally, the molecular docking study revealed good acceptable binding scores of the four major compounds, comparable to those of ECGC and kojic acid. Besides, the SSHF identified phytoconstituents showed no predicted potential toxicity nor skin toxicity, as determined in silico. In conclusion, the antiaging potential of SSHF may be attributed to its high content of vitamin E in addition to the synergetic effect of other volatile constituents. Thus, SSHF could be incorporated in pharmaceutical skin care products and cosmetics after further studies.

Cembranoids from the Vietnamese soft coral Sarcophyton ehrenbergi

Using various chromatographic separations, two new cembranoids, ehrenbergols F and G (1 and 2), along with three known analogs ehrenbergol D (3), (+)-isosarcophine (4) and sinulariol Z₂ (5) were isolated from the soft coral Sarcophyton ehrenbergi. The structural elucidation was done by extensive analysis of the 1 D and 2 D NMR, HR-ESI-QTOF-MS as well as CD experiments. In addition, compounds 1 (IC₅₀ of 38.38 ± 2.89 µM), 3 (IC₅₀ of 37.14 ± 3.22 µM) and 4 (IC₅₀ of 45.01 ± 2.49 µM) revealed moderate inhibitory activity on LPS-induced NO production in RAW264.7 cells, whereas 2 (IC₅₀ of 73.32 ± 1.95 µM) and 5 (IC₅₀ of 64.48 ± 4.93 µM) exhibited weak effect.

Potency of bisresorcinol from Heliciopsis terminalis on skin aging: in vitro bioactivities and molecular interactions

Background

A bisresorcinol was isolated as the main constituent of Heliciopsis terminalis’s trunk (Proteaceae). Recently, resorcinol is applied as an active whitening agent in various cosmetic products. Because of the structural mimic to resorcinol, benefits of the bisresorcinol as an aging-enzyme antagonist were demonstrated in this study.

Methods

The bisresorcinol was purified from the crude ethanolic extract of H. terminalis’s trunk by solvent extraction and preparative chromatography, respectively. Inhibitory activity on collagenase, elastase, and tyrosinase of the compound was investigated by using a different spectroscopic technique. Molecular docking was carried out to predict possible interactions of the substance around the enzyme active sites.

Results

The IC₅₀ values on collagenase of the bisresorcinol and caffeic acid were 156.7 ± 0.7 and 308.9 ± 1.6 µmole L⁻¹, respectively. For elastase activity, the IC₅₀ of 33.2 ± 0.5 and 34.3 ± 0.3 µmole L⁻¹ was respectively determined for the bisresorcinol and ursolic acid. The bisresorcinol was inhibitory to tyrosinase by exhibiting the IC₅₀ of 22.8 µmole L⁻¹, and that of 78.4 µmole L⁻¹ was present for β-arbutin. The bisresorcinol bound to collagenase, elastase, and tyrosinase with the respective binding energies of −5.89, −5.69, and −6.57 kcal mol⁻¹. These binding energies were in the same ranges of tested inhibitors. The aromatic phenol groups in the structure were responsible for principle as well as supporting binding interactions with enzymes. Hydrogen binding due to hydroxyl groups and π-related attractive forces from an aromatic ring(s) provided binding versatility to bisresorcinol.

Conclusion

The bisresorcinol purified from H. terminalis might be useful for inclusion in cosmetic products as an aging-enzyme antagonist.

Chemical Constituents from the Branches and Leaves of Alchornea trewioides

Two new megastigmane glucosides namely trewiosides A (1) and B (2), along with 20α-hydroxypregn-4-en-3-one β-D-glucopyranoside (3), sugeroside (4), and schizandriside (5) were isolated from the branches and leaves of Alchornea trewioides. The structure elucidation was confirmed by extensive analysis of the one and two dimensional (1 and 2D) NMR, electronic circular dichroism (ECD) as well as high resolution electrospray ionization quadrupole time-of-flight (HR-ESI-QTOF) mass spectra. Noteworthily, the isolation of compounds 1 and 2 represents the second finding of megastigmane derivatives with a methoxycarbonyl group at C-5 to date. In addition, compound 3 showed weak cytotoxicity against three human cancer cell lines as A549 (lung carcinoma), HepG2 (hepatocarcinoma), and MCF7 (breast carcinoma). Besides, compounds 2 and 3 exhibited moderate inhibitory effects on lipopolysaccharide (LPS)-induced nitric oxide (NO) production in RAW264.7 cells. Whereas, the remaining compounds 1, 4 and 5 showed weak inhibitory activity.

Chemical constituents from the branches and leaves of Alchornea annamica

Phytochemical investigation of the branches and leaves of Alchornea annamica led to isolation of ten secondary metabolites, including two new megastigmane glucosides alnamicosides A (1) and B (2). The structure elucidation was confirmed by 1 D and 2 D NMR, ECD as well as HR-QTOF-MS experiments. The megastigmane derivatives 1 - 3 exhibited inhibitory effects on LPS-induced NO production in RAW264.7 cells with IC₅₀ values of 78.72 ± 1.90, 77.40 ± 9.40 and 82.16 ± 4.56 µM, respectively. This is the first report on chemical constituents and biological activity of the plant A. annamica.