Distribution profiles of phenolic compounds in a cultivar of wampee (Clausena lansium (Lour.) Skeels) fruits and in vitro anti-inflammatory activity

ETHNOPHARMACOLOGICAL RELEVANCE

The fruits of wampee (Clausena lansium (Lour.) Skeels), which contain significant amounts of phenolics, are frequently applied as traditional medications to prevent or relieve inflammatory symptoms. Green honey wampee (GHW) is a local cultivar specially cultivated in Lianjiang City, Guangdong Province.

AIM OF THE STUDY

This study aimed to investigate phenolic distribution profiles in the peels, seeds and pulp of GHW as well as elucidate the underlying molecular mechanisms of the effective compounds for anti-inflammatory activity.

MATERIALS AND METHOD

Phenolic compounds in the extract were identified through UPLC-MS/MS and their ability to alleviate inflammation was assessed using RAW 264.7 macrophages exposed to lipopolysaccharide.

RESULTS

Among the three parts of GHW fruits, the total phenolic contents followed a descending order of peels > pulp > seeds. Additionally, eighty-six phenols were tentatively determined from the three parts, of which flavonoids accounted for the highest proportion. Furthermore, the phenolic extract of peels, seeds and pulp exhibited potential anti-inflammatory activity through the suppression effect on different pro-inflammatory mediators (NO, IL-6 and TNF-α). Among the three principal phenolic compounds (rutin, quercitrin, isorhamnetin-3-O-neohesperidoside) detected in GHW fruits, quercitrin was proved to be a more important anti-inflammatory compound inhibiting the iNOS and TNF-α mRNA expressions through the suppression effect on the phosphorylation of IκBα and ERK, belonging to the NF-κB and MAPK signaling pathway respectively.

CONCLUSIONS

Not only wampee pulp but also its by-products like peels and seeds are able to be comprehensively utilized as immunomodulatory supplements for daily diets due to their rich phenolic contents.

Structural characterization of a water-soluble acidic polysaccharide CSP-IV with potential anticoagulant activity from fruit pulp of Clausena lansium (Lour.) Skeels Guifei

Four main water-soluble wampee fruit pulp polysaccharides, named CSP-I, CSP-II, CSP-III and CSP-IV, were isolated from Clausena lansium (Lour.) Skeels Guifei, therein CSP-IV content was higher than the others. All components possess certain anticoagulant activity demonstrated by prolonged activated partial thromboplastin time, especially CSP-IV, which suggests that CSP-IV plays anticoagulant effect through disturbing intrinsic coagulation pathway. The wampee polysaccharide CSP-IV with Mw of 510.1 kDa was mainly composed of Gal, Ara and GalA. Backbone of CSP-IV contains Gal, Ara and GalA, two kinds of side chains contain one monosaccharide Gal or Ara, both branch on Gal residue of backbone. CSP-IV has no the conformation of triple helix demonstrated by Congo red test. These results showed that CSP-IV is an acidic polysaccharide with potential anticoagulant activity via targeting intrinsic coagulation pathway.

Chitosan-based edible film incorporated with wampee (Clausena lansium) seed essential oil: Preparation, characterization and biological activities

Chitosan (Ch)-based edible composite films were prepared by incorporating blending wampee seed essential oil (WSEO) into a Ch matrix, using the incorporation ratio as a variable. The physical, mechanical properties, structure morphology and rheological properties were determined using tensile strength (TS), elongation at break (EB), water vapor permeability (WVP) tests together with Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) observations and apparent viscosity and shear rate. In addition, the antimicrobial, antioxidant activities were investigated by the DPPH & ABTS radicals scavenging and inhibition zone assays, respectively. Compared with Ch, the incorporation of WSEO significantly decreased (P < 0.05) the TS, EB, and WVP values, especially when the WSEO ratio reached 1.0 % or higher. Meanwhile, the films exhibited greatly improved visible light barrier performance after WSEO incorporation. Both FTIR spectroscopy and SEM observations reflected the crosslinking between WSEO and Ch. Meanwhile, the composite films demonstrated smaller particle size and weaker rheological viscosities, which enhanced the antimicrobial and antioxidant capabilities when compared with those of Ch. Therefore, this study suggested that WSEO incorporated with Ch is an effective ingredient for the preparation of edible films with enhanced physicochemical and biological properties.

Anti-malarial activity of the alkaloid, heptaphylline, and the furanocoumarin, imperatorin, from Clausena anisata against human Plasmodium falciparum malaria parasites: ex vivo trophozoitocidal, schizonticidal and gametocytocidal approach

BACKGROUND

The erythrocytic stage of the life cycle of the malaria parasite, Plasmodium falciparum, consists of trophozoite, schizont and gametocyte stages in humans. Various anti-malarial agents target different stages of the parasite to produce treatment outcomes. This study reports on the stage-specific anti-malarial activity of heptaphylline and imperatorin against human P. falciparum in addition to their cytotoxicity and selectivity indices (SI).

METHODS

The compounds were isolated from Clausena anisata using column chromatography and their structures elucidated using NMR spectroscopy. The anti-malarial activity was determined by measuring the trophozoitocidal, schizonticidal and gametocytocidal activities of the compounds using the SYBR green assay. Cytotoxicity was evaluated using the tetrazolium-based colorimetric assay.

RESULTS

Heptaphylline and imperatorin produced trophozoitocidal, schizonticidal and gametocytocidal activities with IC50s of 1.57 (0.2317)-26.92 (0.3144) µM with those of artesunate (the standard drug) being 0.00024 (0.0036)-0.0070 (0.0013) µM. In the cytotoxicity assay, the compounds produced CC50S greater than 350 µM and SI of 13.76-235.90. Also, the trophozoitocidal and schizonticidal activities of the compounds were more pronounced than their gametocytocidal activity. Imperatorin was 42.04% more trophozoitocidal than hepthaphyline. However, hepthaphyline has more schizonticidal and gametocytocidal properties than imperatorin.

CONCLUSION

Heptaphylline and imperatorin are promising anti-malarial agents, since they possess potent anti-malarial activity with weak cytotoxicity on RBCs. However, imperatorin is a better anti-malarial prophylactic agent whereas heptaphylline is a better malaria treatment agent.

Anti-Neuroinflammatory Components from Clausena lenis Drake

Clausena lenis Drake (C. lenis) is a folk medicinal herb to treat influenza, colds, bronchitis, and malaria. The 95% and 50% ethanol extract of C. lenis showed significant nitric oxide (NO) inhibition activity in BV-2 microglial cells stimulated by lipopolysaccharide (LPS). Bio-guided isolation of the active extract afforded five new compounds, including a chlorine-containing furoquinoline racemate, (±)-claulenine A (1), an amide alkaloid, claulenine B (2), a prenylated coumarin, claulenin A (3), a furocoumarin glucoside, clauleside A (4), and a multi-prenylated p-hydroxybenzaldehyde, claulenin B (5), along with 33 known ones. Their structures were determined via spectroscopic methods, and the absolute configurations of new compounds were assigned via the electronic circular dichroism (ECD) calculations and single-crystal X-ray diffraction analysis. Compounds 2, 23, 27, 28, 33, and 34 showed potent anti-neuroinflammatory effects on LPS-induced NO production in BV-2 microglial cells, with IC₅₀ values in the range of 17.6–40.9 μM. The possible mechanism was deduced to interact with iNOS through molecular docking.

Visualizing the spatial distribution of metabolites in Clausena lansium (Lour.) skeels using matrix-assisted laser desorption/ionization mass spectrometry imaging

Clausena lansium (Lour.) Skeels (Rutaceae) is a natural bioactive plant. Its roots, stems, leaves, and seeds are widely used in Chinese traditional and folk medicine. Although the characterization and functional analysis of bioactive components in Clausena lansium (Lour.) Skeels has been widely reported, the spatial distribution of these compounds within the main plant tissues remains undefined. Here, we adopted matrix-assisted laser desorption/ionization-mass spectrometry imaging (MALDI-MSI) to reveal the spatial distribution of active alkaloids, coumarins, sugars and organic acids in C. lansium. Using a combined wet and dry matrix covering method to enhance sensitivity, we detected alkaloids throughout the fruit including 3-methylcarbazole and murrastinine which were especially rich in the kernel tissues but were restricted to the stem xylem and medulla and in the leaf epidermal region. Interestingly, murrayanine and heptaphylline were mainly found in pulp tissues with very low content in the stems and leaves while girinimbine was only distributed within the outer kernel skin. Coumarins were mainly distributed in the fruit pericarp and leaf vein tissues but with no clear spatial specificity in stems. Lastly, hexoses were mainly evident in the fruit pulp, although sucrose was also found in the pericarp, pulp, and pulp fibers with citric acid being distributed throughout the fruit. The accurate spatial and chemical information obtained provides new insights into the specific accumulation of metabolites in individual tissues.

A new prenylated coumarin diglycoside with insulin-release promoting activity from Clausena dunniana

A new prenylated coumarin diglycoside, 6-prenylcoumarin-7-O-β-D-apiofuranosyl-(1→6)-β-D-glucopyranoside (1) and five known flavonoid glycosides (2-6) were isolated from the leaves and stems of Clausena dunniana. The structures of these isolates were elucidated based on comprehensive MS, UV, IR, and NMR spectroscopic data analysis and comparison with the data reported in literature. Compounds 2-6 are obtained from the title plant for the first time. All these isolates were evaluated for their insulin-release promoting effects, and compounds 1, 2, and 4 exhibited significant activities (2.0 to 3.3-fold higher in comparison with the control, p < 0.01) at 40 μM.[Formula: see text].

Chemical components from the stems and leaves of Clausena lansium (Lour.) Skeels and their potential herbicidal effects

BACKGROUND

Clausena lansium (Lour.) Skeels, belonging to the genus Clausena of the family Rutaceae, has a wide range of medical and agricultural activities. Previous studies on agricultural activities have shown that C. lansium extracts and some components have obvious herbicidal activities. In order to study systematically herbicidal activity of this plant, we studied the herbicidal effect of ethyl acetate (EtOAc) extract from the stems and leaves of this plant and further isolated the active compounds.

RESULTS

The EtOAc extract inhibited the growth of roots and shoots of Echinochloa crus-galli (L.) Beauv., and the inhibitory effect of the EtOAc extract on roots were stronger than those on shoots with half maximal inhibitory concentration (IC₅₀ ) values of 420.45 and 585.05 mg L^-1 , respectively. Fifteen compounds were subsequently isolated and identified from the stems and leaves of C. lansium, including nine O-monoterpenoid furanocoumarins and six cinnamamides. Our results showed that most compounds exhibited varying degrees of herbicidal activities to E. crus-galli. Among them, compounds 3, 8, and 13-15 showed the best inhibitory activities on the growth of E. crus-galli roots, with inhibition rate values ranging from 70% to 83% at a concentration of 300 mg L^-1 . Compounds 1 and 2 are two new compounds, and their structures were established as 5-O-monoterpenoid furanocoumarin and 8-O-monoterpenoid furanocoumarin, and named as claulansicoumarin-A and -B, respectively.

CONCLUSION

The EtOAc extract and pure compounds showed noticeable herbicidal activities against E. crus-galli and indicated a great potential for these natural compounds to be developed as a herbicide. © 2020 Society of Chemical Industry.

Efficacy of essential oil from Clausena anisata and its impact on biochemical changes of Sitophilus oryzae

Essential oil (EO), from Clausena anisata, was evaluated for their efficacy (fumigant and repellent activities) against Sitophilus oryzae. Result revealed that C. anisata showed 82% fumigant toxicity (insect mortality) at 160 μL/L concentration after 24h observation period. C. anisata exhibited LC₅₀ value of 17.84 μL/L concentration for fumigant toxicity. The insect movement behaviour (repellent) was observed in two different concentrations of 10 and 50 μL for a period of 3 h. Maximum repellent activity (- 0.25) was observed at 50 μL/L concentration against S. oryzae after 3-h observation. At 3, 6 and 12 μL/L concentrations of C. anisata oil significantly reduced the protein content and total esterase activity of S. oryzae.

Lipid-lowering property of Clausena anisum-olens in hypercholesterolemic rats

CONTEXT

Clausena anisum-olens (Blanco) Merr. (Rutaceae) is a medicinal shrub which has been reported to have various pharmacological uses. No study regarding the effects of C. anisum-olens on cholesterol-lowering has been reported.

OBJECTIVE

The effects of the ethanol extract of C. anisum-olens leaves on the cholesterol level of hypercholesterolemic rats were evaluated.

MATERIALS AND METHODS

Acute oral toxicity of the extract (175, 550 and 2000 mg/kg) was determined using female Sprague-Dawley rats, as described in OECD 425 Main test guidelines. The lipid-lowering assay utilized 30 male Sprague-Dawley rats divided into five groups (A-E). Triton X-100 was administered to induce hypercholesterolemia. After hypercholesterolemia induction, oral treatment of Atorvastatin and crude ethanol extract was given daily to the treatment groups for 14 days. The total cholesterol, triglycerides, HDL and LDL were determined before induction, after induction, after first week of treatment and after second week of treatment.

RESULTS

Acute oral toxicity showed the crude extract is nontoxic up to 2000 mg/kg. The lipid-lowering assay indicated reduction of serum cholesterol (87.21 ± 5.10 mg/dL), triglycerides (58.09 ± 4.10 mg/dL) and LDL (27.82 ± 4.11 mg/dL) for 200 mg/kw extract. Reduction in serum cholesterol (74.72 ± 3.64 mg/dL), triglycerides (52.79 ± 2.98 mg/dL) and LDL (12.06 ± 5.51 mg/dL) were observed for 400 mg/kg group. The result is comparable to Atorvastatin, which showed serum cholesterol (80.90 ± 9.72 mg/dL), triglycerides (55.94 ± 7.19 mg/dL) and LDL (22.09 ± 7.60 mg/dL) reduction.

DISCUSSION AND CONCLUSION

The crude extract of C. anisum-olens proved to be useful in lowering of cholesterol.

ex Benth (Rutaceae) in Rodents: possible mechanism of actions

The leaves of Clausena anisata (Willd.) Hook. f. ex Benth (Rutaceae) is used in Traditional African medicine for the treatment of various ailments including arthritis. The present study sought to investigate the antinociceptive and anti-arthritic properties of hydroethanolic leaf extract of Clausena anisata (HeCA). HeCA (100, 200 or 400 mg/kg, p.o.) was administered 1 h before intraplantar injection of formalin 1%v/v in saline to evaluate antinociceptive effect. Moreover, its possible mechanism of antinociceptive action was investigated through pretreatment of mice with antagonists of receptors implicated in nociception. Anti¬inflammatory effect of the extract was investigated using the carrageenan-induced paw oedema and complete Freund's adjuvant (CFA)-induced arthritis models in rats. HeCA (400 mg/kg) treatment significantly reduced the duration of paw licking/biting during both in the early (42.12%) and late (75.79%) phases of formalin-induced nociception. However, the antinociceptive effect elicited by HeCA was reverse by pretreatment of mice with naloxone, prazosin, yohimbine, ketanserin, L-arginine, and parachlorophenylalanine (PCPA). HeCA produced dose-dependent and time course decrease in carrageenan-induced paw oedema. Pre- and post-treatment of rats with HeCA ameliorated CFA-induced arthritis evidenced in the significant decrease in arthritic index comparatively similar to the effect of celecoxib. CFA- induced oxidative and nitrosative stress were attenuated by subchronic treatment with HeCA. Findings from this study shows that C. anisata possesses antinociceptive activity through possible interaction with opioidergic, noradrenergic, L-arginine-nitric oxide and serotonergic pathways as well as anti-arthritic property which could be attributed to its ability to prevent the release of inflammatory mediators and oxidative stress.

(Diptera: Culicidae) mosquito

BACKGROUND

Plant based repellent against mosquito borne diseases are used recently because synthetic repellents cause side effects like breathing problem, eye irritation, head ache, cough, etc. The use of natural products for dengue control would protect the environment, reduce dependence on expensive synthetic repellents and also generate local employment.

MATERIAL AND METHODS

Essential oil was isolated by steam distillation which was used against the bites of Aedes aegypti and duration of protection period was assessed. Skin-irritant potential test was also conducted on 25 healthy volunteers by using four-point scale.

RESULTS

The increase in the concentrations of essential oil increased the mean protection time against the bites of Aedes aegypti. The lowest mean protection time was 180.0 min for 2.5% and highest time of 255.0 min for 10%. The mean score of zero for skin-irritant potential test for all the concentrations indicated that the essential oil did not cause irritation to human skin.

CONCLUSIONS

Results indicated that the use of plant based repellent for the control of dengue fever would replace the currently used synthetic repellents which causes many side effects.

against paracetamol induced hepatotoxicity in rats

Ethanol extract of Clausena dentata (Willd.) M. Roem (Rutaceae) was evaluated for hepatoprotective activity in rats. The plant extract (250 mg/kg, p.o.) showed a remarkable hepatoprotective activity against acetaminophen-induced hepatotoxicity as judged from the serum markers for liver damage. Acetaminophen induced a significant rise in aspartate amino transferase (AST), alanine amino transferase (ALT), alkaline phosphatase (ALP), total bilirubin, gamma glutamate transpeptidase (GGTP) and decrease in total protein. Treatment of rats with ethanol extract (250 mg/kg) significantly (P<0.001) altered serum marker enzymes levels to near normal against acetaminophen treated rats. The activity of the extract was comparable to the standard drug, silymarin (50 mg/kg, p.o.). Histopathological changes of liver sample were compared with respective control. Results indicate that Clausena dentata possesses hepatoprotective effect on acetaminophen-induced hepatotoxicity in rats.