Chemical constituents and antihistamine activity of Bixa orellana leaf extract

Exploring antioxidative, cytotoxic and neuropharmacological insights into Bixa orellana leaves: Experimental and in silico approaches

Background Study

The aim of this research was to examine possible antioxidant, cytotoxic and neurological activity of methanol and n-hexane extracts of Bixa orellana leaves. Additionally, we aimed to identify potential lead compounds through in-silico analysis.

Methods

In-vitro antioxidative properties were investigated through different assays, including: total phenolic content assay (TPC), total flavonoid content assay (TFC), DPPH free radical scavenging assay and reducing power assay. Also, the cytotoxic effect of the samples was assessed using the brine shrimp lethality test. In addition, anxiolytic, locomotor, and CNS depressant activities were assessed utilizing various established methods. Moreover, reported compounds were used in the in silico study to explore the best-fit phytoconstituents against gamma-aminobutyric acid (GABAA) receptor.

Results

MBOL displayed substantial antioxidative activities in various established assays compared to NBOL. In brine shrimp lethality bioassay, both MBOL and NBOL revealed cytotoxic activity in a concentration-dependent approach. Again, in Elevated Plus Maze test, 200 and 400 mg/kg of NBOL and MBOL demonstrated significant anxiolytic activities evident from time spent in open arms. In addition, maximum number of head dipping was demonstrated by MBOL at 400 mg/kg (53.90 ± 1.16) in Hole Board test. NBOL and MBOL at both doses significantly diminished the magnitude of movements from the 2nd to 5th observation periods in Open Field test. Furthermore, in Hole Cross test, MBOL remarkably dwindled the locomotor activity at 120 min and 180 min (3.60 ± 0.40 and 2.40 ± 0.51) at 400 mg/kg. Finally, in silico analysis revealed 13 compounds as promising leads with strong binding affinity to GABAA receptor along with good pharmacokinetics and toxicity profiles.

Conclusion

Therefore, the present study's findings advocate the traditional usage of this plant and recommend both MBOL and NBOL as as a potential source of therapeutic candidate for the management of neurological disorders.

Investigation on the effect of antimicrobial photodynamic therapy as an adjunct for management of deep caries lesions-study protocol for a randomized, parallel groups, controlled clinical trial

BACKGROUND

Alternatively to conventional treatments, chemo-mechanical caries removal agents can be used. A modality of treatment that has been increasing in dentistry is antimicrobial photodynamic therapy (aPDT). Bixa orellana is being researched for application in aPDT. This protocol aims to determine the effectiveness of aPDT with Bixa orellana extract in deep caries lesions.

METHODS

A total of 160 teeth with deep occlusal dental caries will be selected and divided into 4 groups: G1 - control group (Caries removal with a low-speed drill); G2 - Partial Caries Removal with Papacarie™ (Fórmula e Ação, São Paulo, SP, Brazil); G3 - Partial Caries Removal with Papacarie™ and application Bixa orellana extract (20%) (Fórmula e Ação, São Paulo, SP, Brazil); G4 - Partial Caries Removal with Papacarie™ and application Bixa orellana extract (20%) with LED (Valo Cordless Ultradent®, South Jordan, UT, USA) (aPDT). After treatment, all the teeth will be restored with glass ionomer cement and followed up clinically and radiographically, with evaluations at immediately, 1 week, and 1, 3, 6, and 12 months. Dentin samples before and after treatment will be analyzed microbiologically. The efficacy of treatments will be assessed with microbiological (colony-forming units, before and after carious tissue removal), radiographic (integrity of the periapical area and eventual changes in the radiolucent zones), and clinical examinations (retention of the restorative material in the cavity and occurrence of secondary caries), as well as with the time required for the procedures and the need for anesthesia during the procedures. In case data distribution is normal, analysis of variance (ANOVA) will be used for both the dependent and independent variables. In case the data distribution is not normal, the Friedman test will be used for the dependent variables. For independent variables, the Kruskal-Wallis test will be used.

DISCUSSION

Procedures using aPDT have been developed for the treatment of dental caries, but there are few controlled clinical trials in the literature confirming its efficacy.

TRIAL REGISTRATION

This protocol is registered at ClinicalTrials.gov under the number NCT05236205 and it was first posted on 01/21/2022 and last updated on 05/10/2022.

Chemical profiles and pharmacological attributes of Apis cerana indica beehives using combined experimental and computer-aided studies

The current study sought to determine the anxiolytic, antidepressant, and anti-inflammatory properties of distilled water-soluble extract of beehive (WSE-BH). Gas chromatography-mass spectrometry (GC-MS) studies were used to characterize the chemical compositions obtained from beehives extracted in water and methanol (also fractions). The GC-MS analysis identified 19 compounds in WSE-BH, including high total phenol and flavonoid contents, compared with the methanol extract (21 compounds), ethyl acetate fraction (9 compounds), and CCl₄ fraction (27 compounds). The oral administration of WSE-BH (50 and 150 mg/kg) showed significant anxiolytic activities assessed by time spent in (30.80% and 39.47%, respectively) and entry into (47.49% and 55.93%, respectively) the open arms of the elevated plus-maze (EPM). Only the 150 mg/kg dose resulted in a significant effect on the number of head-dipping events in the hole-board test (HBT) (40.2 ± 2.33; p < 0.01) vs. diazepam (64.33 ± 3.16; p < 0.001). Both the 50 and 150 mg/kg doses resulted in significant (p < 0.001) decreases in immobility in the forced swim test (FST) and tail suspensions test (TST), corresponding to the effect of fluoxetine. WSE-BH inhibited histamine-induced paw edema significantly beginning at 60 min, with the 150 mg/kg dose having the highest effect at 180 min. The current findings suggested that WSE-BH had anxiolytic, antidepressant, and anti-inflammatory properties.

Evaluation of Phytochemistry and Pharmacological Properties of Alnus nitida

In the current study, the anti-inflammatory and analgesic potential of Alnus nitida (leaves and fruits) was evaluated in the Sprague-Dawley rat. Traditionally, A. nitida was used for the treatment of inflammatory ailments. However, A. nitida leaves and fruits have not been yet reported regarding any potential medicinal effects. Leaves/fruits of A. nitida were extracted with methanol and fractionated to attain n-hexane, chloroform, ethyl acetate and aqueous fractions. These extracts were then evaluated for in vivo analgesic and anti-inflammatory potential. For in vivo anti-inflammatory activity, carrageenan-induced paw edema assay, Freunds’ complete adjuvant-induced edema, xylene-induced ear edema and histamine-induced paw edema models were used in rats, which showed significant (p < 0.01) reduction (70−80%) in edema in comparison of inflammatory controls. On other hand, for the analgesic assessment, hot plate assay and acetic acid-induced writhing tests were used, which showed a significant (p < 0.01) rise in latency time (40−60%) as compared with pain-induced controls. These results were comparable with standard drugs in a concentration-dependent manner and no mortality or toxicity was observed during all experiments. Then, for the identification of chemical constituents gas chromatography−mass spectrometry (GC-MS) analysis was performed, which indicated the presence of neophytadiene, 3,7,11,15-Tetramethyl-2-hexadecen-1-ol, phytol and vitamin E, justifying the use of A. nitida to treat inflammatory disorders.

Anti-Inflammatory Medicinal Plants of Bangladesh—A Pharmacological Evaluation

Inflammatory diseases are considered major threats to human health worldwide. In Bangladesh, a number of medicinal plants have been used in traditional medicine from time immemorial in the treatment of diverse diseases, including inflammatory disorders. This assignment aims at providing the status of the medicinal plants of Bangladesh which are traditionally used in the management of inflammatory disorders and are investigated for their anti-inflammatory prospects using different preclinical studies and future research directions. The information of medicinal plants assembled in this review was obtained from a literature search of electronic databases such as Google Scholar, PubMed, Scopus, Web of Science and ScienceDirect up to December, 2020 from publications on plants investigated for their anti-inflammatory activities, in which the place of plant sample collection was identified as Bangladesh. Keywords for primary searches were “anti-inflammatory,” “Bangladeshi,” and “medicinal plants.” Criteria followed to include plant species were plants that showed significant anti-inflammatory activities in 1) two or more sets of experiments in a single report, 2) same or different sets of experiments in two or more reports, and, 3) plants which are traditionally used in the treatment of inflammation and inflammatory disorders. In this study, 48 species of medicinal plants have been reviewed which have been used in traditional healing practices to manage inflammatory disorders in Bangladesh. The mechanistic pathways of the in vivo and in vitro study models used for the evaluation of anti-inflammatory properties of plant samples have been discussed. Selected plants were described in further detail for their habitat, anti-inflammatory studies conducted in countries other than Bangladesh, and anti-inflammatory active constituents isolated from these plants if any. Medicinal plants of Bangladesh have immense significance for anti-inflammatory activity and have potential to contribute toward the discovery and development of novel therapeutic approaches to combat diseases associated with inflammation. However, the plants reviewed in this article had chiefly undergone preliminary screening and require substantial investigations including identification of active molecules, understanding the mechanism of action, and evaluation for safety and efficacy to be followed by the formulation of safe and effective drug products.

Isolation, Identification, Spectral Studies and X-ray Crystal Structures of Two Compounds from Bixa orellana, DFT Calculations and DNA Binding Studies

4,6-Diacetylresorcinol (1) and 3-O-methylellagic acid dihydrate (2), both biologically significant compounds, were extracted from Bixa orellana and studied using IR, 1H, and 13C NMR, and UV-vis spectroscopic techniques. X-ray crystallographic techniques were also used to establish the molecular structure of the isolated compounds 1 and 2. Geometric parameters, vibrational frequencies, and gauge including atomic orbital (GIAO) 1H and 13C NMR of 1 and 2 in the ground state were computed by the density functional theory (DFT) using B3LYP/6-311G(d,p) basis set backing up experimental studies and established the correct structure of isolated compounds. The parameters obtained from the combined DFT, and X-ray diffraction studies are mutually agreed to establish correct structures of 1 and 2. In addition, an electrostatic potential map and HOMO−LUMO energy gap were made using the DFT calculation to determine the distribution of energy and the chemical reactivity region of the isolated compounds. The current study also provides further insights into the interaction of compound 2 with ct-DNA using numerous biophysical and in silico techniques. Moreover, in silico studies indicate that compound 2 binds to the DNA in the minor groove. Lipinski’s rule of five revealed a higher tendency of compound 2 towards drug-likeness. The bioavailability and synthetic accessibility score for compound 2 was found to be 0.55 and 3.21, suggesting that compound 2 could serve as an effective therapeutic candidate.

Comparative toxicity, phytochemistry, and use of 53 Philippine medicinal plants

The study compares the toxicity of 53 selected medicinal plants commonly used in the Philippines to treat various diseases. It uses as a benchmark Vitex negundo L., which was approved by the Philippine Food and Drug Administration as an herbal drug for cough and asthma after passing clinical trials for safety and efficacy. The methods were chosen for their simplicity and accessibility even for resource-limited laboratories. Extracts (95 % ethanol) of the medicinal parts of the plants were (1) chemically profiled using qualitative phytochemical tests that detect the presence of key classes of bioactive compounds; and (2) evaluated for toxicity using the brine shrimp (Artemia sp.) lethality assay (BSLA). General phytochemical screening revealed the presence of tannins in 50 plant extracts, alkaloids in 43, glycosides in 33, flavonoids in 31, steroids in 21, triterpenoids in 20, anthraquinones in 10, and saponins in 8. Extracts from eight plants had LC₅₀ values lower than the potassium dichromate control (approximately 12 μg/mL) and were considered highly toxic; extracts from 21 plants had LC₅₀ values between 12 μg/mL and 100 μg/mL and were considered moderately toxic; extracts from 19 plant extracts, including Vitex negundo and some common vegetables, had LC₅₀ values between 100 μg/mL and 500 μg/mL, and were considered mildly toxic and likely to have reasonable safety margins; five plant extracts, including common vegetables, had LC₅₀ values above 500 μg/mL and were considered essentially nontoxic. No apparent correlation could be found between toxicity and chemical diversity or a specific class of phytochemicals present. Our findings may serve as a guide for herbal drug and nutraceutical development, especially in prioritizing plants for more detailed safety studies.

Qualitative and quantitative phytochemical composition, antimicrobial activity, and brine shrimp cytotoxicity of different solvent extracts of Acanthus polystachyus, Keetia gueinzii, and Rhynchosia elegans

Background

The root, root bark, and root tubers of Acanthus polystachyus, Keetia gueinzii, and Rhynchosia elegans are used for managing bacterial and fungal infections among the Luo community of Kisumu East Sub County in Kenya. However, data on the efficacy of these plants against common bacterial and fungal pathogens is not available. The safety of these plants is also not known. This study aimed to investigate the phytochemical composition, antimicrobial properties, and safety of different solvent extracts of the roots, root barks, and root tubers of Acanthus polystachyus, Keetia gueinzii, and Rhynchosia elegans. The broth microdilution method evaluated the antimicrobial activities of the root, root bark, and root tuber extracts (water, acetone, and methanol) of Acanthus polystachyus, Keetia gueinzii, and Rhynchosia elegans. Gram-positive (Bacillus cereus, Staphylococcus aureus), gram-negative (Escherichia coli), and fungal (Candida albicans) microorganisms were used in the evaluation. The safety of the extracts was evaluated in Artemia salina. The phytochemical composition of the extracts was determined using qualitative and quantitative assays.

Results

In general, the extracts of Acanthus polystachyus, Keetia gueinzii, and Rhynchosia elegans displayed poor antimicrobial properties relative to conventional antimicrobial agents including Amoxicillin, Gentamicin, and Nystatin. The aqueous extract of Acanthus polystachyus and the aqueous, acetone, and methanol extracts of Keetia gueinzii were safe in Artemia salina but all other extracts were cytotoxic to Artemia salina.

Conclusions

These findings suggest that the use of the roots, root barks, and root tubers of Acanthus polystachyus, Keetia gueinzii, and Rhynchosia elegans is limited by poor antimicrobial efficacy and cytotoxicity.

Antimicrobial photodynamic therapy with Bixa orellana extract and blue LED in the reduction of halitosis-A randomized, controlled clinical trial

BACKGROUND

This study aimed to evaluate the reduction of halitosis when using antimicrobial photodynamic therapy (aPDT) with Bixa orellana extract and blue light-emitting diode (LED).

METHODS

Forty-four UNINOVE students or employees with a diagnosis of sulfide (H2S) ≥ 112 ppb in gas chromatography were selected. The patients were randomly divided in groups: Group 1 (n = 15): aPDT with annatto and LED; Group 2 (n = 14): tongue scraping; Group 3 (n = 15): tongue scraping and aPDT. For aPDT, a wasBixa orellana extract used in a concentration of 20 % w/v (Fórmula e Ação®, São Paulo, Brazil) on the tongue for 2 min, associated with a blue-violet LED (Valo Cordless Ultradent® Products, Inc., South Jordan, UT, USA) (395-480 nm). Six points were irradiated on the back of the tongue, at wavelength 395-480 nm for 20 s, energy of 9.6 J and radiant energy of 6.37 J/cm² per point. The results were compared before, immediately after treatment and 7 days after. The Friedman test was used for the intragroup analysis and the Kruskal Wallis test for the intergroup analysis.

RESULTS

In all groups, there was a difference between baseline and the value immediately after the treatment. In Groups 1 and 3, there was no difference between the baseline and the 7 days control.

CONCLUSION

There was an immediate reduction of halitosis, but the reduction was not maintained after 7days.

Plasma fatty acid profile in dairy cows associated with the inclusion of annatto in their diet

The objective of this study was to evaluate the plasma lipid profile and plasma fatty acids of dairy cows receiving diets supplemented with annatto. A total of 32 Holstein cows (550 kg), distributed in a completely randomized design, were allocated to individual stalls and submitted to following treatments: C0 = no annatto; C4 = inclusion of annatto at 4 g kg-1 dry matter (DM) of diet (0.07 g bixin kg-1 diet); C5 = inclusion of annatto at 5 g kg-1 DM of diet (0.09 g bixin kg-1 diet); and C7 = inclusion of annatto at 7 g kg-1 DM of diet (0.12 g bixin kg-1 diet). Blood samples were collected via epigastric vein puncture, centrifuged, and frozen for subsequent analysis. The results indicate that the inclusion (p > 0.05) of annatto does not decrease the total cholesterol or low and high density lipoproteins. However, it impacts the profile of fatty acids, evidenced by the reduction (p < 0.05) in levels of hypercholesterolemic fatty acids viz, myristic acid and palmitic acid.  It also causes an increase in the levels of arachidonic acid, rumenic acid, linoleic acid, and total polyunsaturated fatty acids. Therefore, bixin included in the diets of dairy cows induces changes in the plasma fatty acid profile.

Anti-oxidant and anti-inflammatory potential of aqueous extracts of leaves, barks and roots of Bixa orellana L. (Bixaceae) on acetaminophen-induced liver damage in mice

OBJECTIVE

Bixa orellana is a plant from the Bixaceae family, for which, limited information is available on hepatoprotective properties. This study aimed at evaluating the protective effects of this plant on sub-acute acetaminophen (APAP)-induced liver injury in mice.

MATERIALS AND METHODS

Various aqueous extracts were prepared from roots, leaves, and barks. Albino mice were divided into six groups: a control group, an APAP group; a silymarin group (positive control) and three test groups. Mice were treated orally with APAP (250 mg/kg) followed 3 hr later by plant extracts, silymarin (50 mg/kg) or distilled water (10 ml/kg) administration once daily, for seven days. After treatment, animals were sacrificed, the liver was collected and different biochemical parameters were measured. Histological analyses were performed using hematoxylin/eosin staining and the qualitative phytochemical content of plant extracts was evaluated using conventional methods.

RESULTS

Administration of B. orellana barks decoction (250 mg/kg) significantly reduced alanine aminotransferase levels (p<0.001), unlike leaves and roots extracts. Moreover, the bark infusion had the highest activity compared to macerate and decoction. It significantly reduced malondialdehyde levels (p<0.001) and increased the levels of glutathione, superoxide dismutase and catalase, at doses of 250 and 500 mg/kg compared to the APAP group. A significant (p<0.001) decrease of tumor necrosis factor-α levels and leukocyte infiltration was found following treatment with bark infusion. The infusion content evaluation revealed the presence of polyphenols, saponins, tannins, sterols, anthraquinones, and coumarins and the absence of alkaloids.

CONCLUSION

These results show that infusion from B. orellana barks is hepatoprotective against APAP-induced toxicity via antioxidant and anti-inflammatory mechanisms.

Hydroalcoholic Extract and Ethyl Acetate Fraction of Bixa orellana Leaves Decrease the Inflammatory Response to Mycobacterium abscessus Subsp. massiliense

The incidence of infections caused by rapidly growing mycobacteria (RGM), especially Mycobacterium abscessus subsp. massiliense (Mabs), is increasing worldwide. Severe infections are associated with abscess formation and strong inflammatory response. This study evaluated the antimicrobial and anti-inflammatory activities of a hydroalcoholic extract (BoHE) and ethyl acetate fraction (BoEA) of Bixa orellana leaves. Antimicrobial activity was evaluated by broth microdilution to determine the minimum inhibitory (MIC) and the minimum bactericidal (MBC) concentrations. Cytotoxicity was evaluated using erythrocytes and RAW 264.7 cells. Nitric oxide (NO) was assayed in stimulated RAW 264.7 cells, and inflammatory cell migration and acute toxicity were evaluated in a Mabs-induced peritonitis mouse model. The compounds present in BoEA were identified by high performance liquid chromatography and mass spectrometry (HPLC-MS). The MIC and MBC values were 2.34 mg/mL and 37.5 mg/mL for BoHE and 0.39 mg/mL and 6.25 mg/mL for BoEA. The extracts did not induce significant toxicity in erythrocytes and RAW 264.7 cells. High levels of NO induced by Mabs were decreased by treatment with both extracts. The anti-inflammatory activity was confirmed in vivo by significant reduction of the cell migration to the peritoneum following BoHE and BoEA pretreatment. Animals treated with BoHE or BoEA did not show signs of acute toxicity in stomach, liver, and kidney. The chemical characterization of BoEA (the most active extract) revealed that kaempferol-3-O-coumaroyl glucose is its major component. The extract of B. orellana may be effective for treating infections caused by Mabs.

Ipomoea batatas L. Lam. ameliorates acute and chronic inflammations by suppressing inflammatory mediators, a comprehensive exploration using in vitro and in vivo models

BACKGROUND

Ipomoea batatas L. Lam. is a functional food and belongs to family Convolvulaceae. It is used as an antiinflammatory, aphrodisiac, antiasthmatic, anticonvalescent, antitumor, antanemic and antidiabetic agent by local communities. This study has been planned to evaluate its antiinflammatory and antiarthritic potentials.

METHODS

Dry powder of I. batatas tuber and roots were extracted with ethyl acetate (IPT-EA, IPR-EA) and methanol (IPT-M, IPR-M), respectively. These extracts were tested for total phenolic and flavonoid contents (TPC and TFC), HPLC finger printing, multidimensional in vitro and in vivo antioxidant potential and albumin denaturation inhibition. Carrageenan-induced paw edema, croton oil-induced ear and anal edema inhibition and Complete Freund's Adjuvant (CFA)-induced antiarthritic assays were executed at a dose of 300 mg/kg body weight on Sprague-Dawley rats. Serum levels of interleukins IL-1β and IL-6 and nitric oxide (NO) were assessed to measure the inhibition of inflammation.

RESULTS

Maximal TPC (319.81 ± 14.20 μg GAE/mg dry extract) and TFC (208.77 ± 9.09 μg QE/mg DE) were estimated in IPR-EA extract. IPT-EA and IPR-EA yielded the maximum amounts of rutin (7.3 ± 1.12 and 4.5 ± 0.55), caffeic acid (1.60 ± 0.25 and 2.17 ± 0.26) and myricetin (2.7 ± 0.14 and 1.01 ± 0.08 μg/mg DE), respectively in HPLC-DAD analysis. All extracts showed dose dependent response in in vitro antioxidant assays. Best inhibition (76.92 ± 3.07%) of albumin denaturation was shown by IPT-EA in comparison to ibuprofen (79.48 ± 4.71%). IPR-EA exhibited highest edema inhibition in models of carrageenan-induced paw edema (79.11 ± 5.47%) and croton oil-induced ear and anal edema (72.01 ± 7.80% and 70.80 ± 4.94%, respectively). Significant inhibition of CFA-induced arthritic edema and arthritic score were observed by IPR-EA as compared to ibuprofen. Suppression of pro-inflammatory cytokines (IL-1β, IL-6) and NO levels was shown by IPR-EA and IPT-EA, respectively.

CONCLUSION

These results depict that richness of polyphenols and phytoconstituents in I. batatas ameliorates oxidative stress and inflammation of acute and chronic nature. Dose dependent antioxidant potential and inhibition of inflammatory edema, pro-inflammatory cytokines and hematological, biochemical and histological changes prove I. batatas therapeutic potential as an antiinflammatory and antiarthritic agent.

Investigations on anti-inflammatory and analgesic activities of Alnus nitida Spach (Endl). stem bark in Sprague Dawley rats

ETHNOPHARMACOLOGICAL RELEVANCE

Stem bark of Alnus nitida (Spach) Endl. (family Betulaceae) is used by local communities in northern areas of Pakistan as a remedy for swelling, injuries and pain. However no pharmacological study of this plant has been reported to confirm these activities. In this study anti-inflammatory and analgesic effect of A. nitida stem bark have been evaluated.

METHODS

Powder of the stem bark of A. nitida was extracted with methanol (ANBM) and partitioned in escalating polarity to get the n-hexane (ANBH), chloroform (ANBC), ethyl acetate (ANBE) and the residual soluble aqueous (ANBA) fractions. The methanol extract and derived fractions were evaluated for anti-inflammatory activity by using in vitro heat induced albumin denaturation assay and various in vivo assays; carrageenan-induced hind paw edema method, Freunds' complete adjuvant induced arthritis, histamine induced paw edema and xylene induced ear edema in Sprague Dawley rat. The extracts/fractions were also evaluated for analgesic effects by using hot plate analgesic test and acetic acid induced writhing test in rat. The ANBM composition was analyzed by HPLC-DAD and GC-MS analysis.

RESULTS

Results of heat induced albumin denaturation activity indicated that among the extract/fractions ANBC at concentration range of 100-500µg/ml remarkably protected the heat induced albumin denaturation. The pretreatment with ANBC significantly reduced the carrageenan induced edema with 90.81±1.6% after 4h, comparing with 86.63±3.42% reduction produced by the reference drug diclofenac potassium. Histopathological alterations of the gastric and hind paw were decreased with the extract/fractions. Furthermore, anti-inflammatory effects of ANBC were evident in Freunds' complete adjuvant induced arthritis, histamine induced paw edema and xylene induced ear edema. The latency time in hot plate analgesic assay with ANBC (61.59±0.38%) after 90min was comparable to standard drug morphine (69.31±2.67%) and aspirin (67.24±2.08%). Similarly ANBC significantly (p<0.01) inhibited the pain sensation in acetic acid induced writhing test in rat. HPLC-DAD analysis of ANBM indicated the presence of gallic acid, catechin and rutin while the GC-MS analysis of ANBM indicated the presence of 30 compounds predominantly of neophytadiene, 3,7,11,15 tetramethyl-2-hexadecen-1-ol, phytol, vitamin E and linalool.

CONCLUSION

The results of this study suggested that the presence of polyphenols, sterols, terpenoids and other constituents might contributed towards the anti-inflammatory and analgesic activities of the crude methanol extract of A. nitida bark and its derived fractions. This study endorsed the folklore use of A. nitida bark for inflammation related disorders.

Carotenoid Derivates in Achiote (Bixa orellana) Seeds: Synthesis and Health Promoting Properties

Bixa orellana (family Bixaceae) is a neotropical fast growing perennial tree of great agro-industrial value because its seeds have a high carotenoid content, mainly bixin. It has been used since pre-colonial times as a culinary colorant and spice, and for healing purposes. It is currently used as a natural pigment in the food, in pharmaceutical, and cosmetic industries, and it is commercially known as annatto. Recently, several studies have addressed the biological and medical properties of this natural pigment, both as potential source of new drugs or because its ingestion as a condiment or diet supplement may protect against several diseases. The most documented properties are anti-oxidative; but its anti-cancer, hypoglucemic, antibiotic and anti-inflammatory properties are also being studied. Bixin's pathway elucidation and its regulation mechanisms are critical to improve the produce of this important carotenoid. Even though the bixin pathway has been established, the regulation of the genes involved in bixin production remains largely unknown. Our laboratory recently published B. orellana's transcriptome and we have identified most of its MEP (methyl-D-erythritol 4-phosphate) and carotenoid pathway genes. Annatto is a potential source of new drugs and can be a valuable nutraceutical supplement. However, its nutritional and healing properties require further study.

Phytochemistry, biological activities and potential of annatto in natural colorant production for industrial applications - A review

Bixa orellana commonly known as annatto is one of the oldest known natural dye yielding plants native to Central and South America. Various parts of annatto have been widely used in the traditional medical system for prevention and treatment of a wide number of health disorders. The plethora of traditional uses has encouraged researchers to identify and isolate phytochemicals from all parts of this plant. Carotenoids, apocarotenoids, terpenes, terpenoids, sterols, and aliphatic compounds are main compounds found in all parts of this plant and are reported to exhibit a wide range of pharmacological activities. In recent years annatto has received tremendous scientific interest mainly due to the isolation of yellow-orange natural dye from its seeds which exhibits high biodegradability, low toxicity, and compatibility with the environment. Considerable research work has already been done and is currently underway for its applications in food, textile, leather, cosmetic, solar cells, and other industries. The present review provides up-to-date systematic and organized information on the traditional usage, phytochemistry and pharmacology of annatto. It also highlights its non-food industrial applications in order to bring more interest on this dye plant, identifies the existing gaps and provides potential for future studies. Studies reported in this review have demonstrated that annatto holds a great potential for being exploited as source of drugs and a potential natural dye. However, further efforts are required to identify extract biomolecules and their action mechanisms in exhibiting certain biological activities in order to understand the full phytochemical profile and the complex pharmacological effects of this plant.

Bixa orellana leaf extract suppresses histamine-induced endothelial hyperpermeability via the PLC-NO-cGMP signaling cascade

BACKGROUND

Histamine is established as a potent inflammatory mediator and it is known to increased endothelial permeability by promoting gap formation between endothelial cells. Previous studies have shown that aqueous extract of Bixa orellana leaves (AEBO) exhibits antihistamine activity in vivo, yet the mechanism of its action on endothelial barrier function remains unclear. Therefore, the current study aimed to determine the protective effect of AEBO against histamine-induced hyperpermeability in vitro.

METHODS

The endothelial protective effect of AEBO was assess using an in vitro vascular permeability assay kit. Human umbilical vein endothelial cells (HUVEC) were used in the current study. HUVEC were pre-treated with AEBO for 12 h before histamine induction. Vascular permeability was evaluated by the amount of FITC-dextran leakage into the lower chamber. In order to elucidate the mechanism of action of AEBO, phospholipase C (PLC) activity, intracellular calcium level, nitric oxide (NO) concentration, cyclic guanosine monophosphate (cGMP) production and protein kinase C (PKC) activity were determined following histamine challenge.

RESULTS

Histamine-induced increased HUVEC permeability was significantly attenuated by pretreatment with AEBO in a time- and concentration-dependent manner. Upregulation of PLC activity caused by histamine in HUVEC was suppressed by pretreatment with AEBO. Pretreatment with AEBO also blocked the production of intracellular calcium induced by histamine in HUVEC. In addition, AEBO suppressed the NO-cGMP signaling cascade when HUVEC were challenged with histamine. Moreover, PKC activity was significantly abolished by pretreatment with AEBO in HUVEC under histamine condition.

CONCLUSION

In conclusion, the present data suggest that AEBO could suppress histamine-induced increased endothelial permeability and the activity may be closely related with the inhibition of the PLC-NO-cGMP signaling pathway and PKC activity.

Suppressions of serotonin-induced increased vascular permeability and leukocyte infiltration by Bixa orellana leaf extract

The aim of the present study was to evaluate the anti-inflammatory activities of aqueous extract of Bixa orellana (AEBO) leaves and its possible mechanisms in animal models. The anti-inflammatory activity of the extract was evaluated using serotonin-induced rat paw edema, increased peritoneal vascular permeability, and leukocyte infiltrations in an air-pouch model. Nitric oxide (NO), indicated by the sum of nitrites and nitrates, and vascular growth endothelial growth factor (VEGF) were measured in paw tissues of rats to determine their involvement in the regulation of increased permeability. Pretreatments with AEBO (50 and 150 mg kg⁻¹) prior to serotonin inductions resulted in maximum inhibitions of 56.2% of paw volume, 45.7% of Evans blue dye leakage in the peritoneal vascular permeability model, and 83.9% of leukocyte infiltration in the air-pouch model. 57.2% maximum inhibition of NO and 27% of VEGF formations in rats' paws were observed with AEBO at the dose of 150 mg kg⁻¹. Pharmacological screening of the extract showed significant (P < 0.05) anti-inflammatory activity, indicated by the suppressions of increased vascular permeability and leukocyte infiltration. The inhibitions of these inflammatory events are probably mediated via inhibition of NO and VEGF formation and release.

Antileishmanial activity of the essential oil from Bixa orellana

Leishmaniasis is a neglected tropical disease caused by Leishmania protozoa. There is currently no vaccine against leishmaniasis, and chemotherapy remains the only effective control. However, conventional drugs are toxic, expensive, and require long periods of treatment, and resistance to clinical chemotherapeutic agents is emerging. Recent research on plants has shown a successful approach to obtain new antileishmanial alternatives. Herein, the in vitro and in vivo effects of the essential oil from Bixa orellana seeds against Leishmania amazonensis were evaluated. A total of 73 compounds were detected by gas chromatography-mass spectrometry analysis, of which ishwarane (18.6%) and geranylgeraniol (9.1%) were the major components. The oil showed activity against intracellular amastigote form (IC50  = 8.5 µg/mL), while the cytotoxic concentration was sevenfold higher for the host cells. The ability of Bixa oil to control disease progression of established cutaneous leishmaniasis in BALB/c mice was demonstrated, after a treatment with 30 mg/kg by intraperitoneal administration over 14 days. The present study reports for the first time the antileishmanial potentialities of the essential oil from B. orellana.