Assessment of pharmacological activities of two medicinal plant of Bangladesh: Launaea sarmentosa and Aegialitis rotundifolia roxb in the management of pain, pyrexia and inflammation

Ethnobotanical study of plants used by the Munda ethnic group living around the Sundarbans, the world's largest mangrove forest in southwestern Bangladesh

ETHNOPHARMACOLOGICAL RELEVANCE

Indigenous knowledge of medicinal plants is an integral part of the primary health care (PHC) system in almost every society. For more than two centuries, Munda, a small ethnic group in Bangladesh, has lived around the Sundarbans, the world's largest mangrove forest. This mangrove is rich in biodiversity but is threatened by global climate change. Information on the therapeutic use of plants by Munda ethnic minorities remains completely unknown. Therefore, it needs urgent documentation.

AIM OF THE STUDY

The purpose of the study is (1) to search and compile data on the diversity of medicinal plants used by the Munda people for PHC needs, and (2) Quantitative analysis of these data to identify important medicinal plants and diseases related to treatment by this species.

MATERIAL AND METHODS

We conducted repeated field surveys and interviews among 79 Munda informants to collect ethnobotanical data. Informants were selected through random sampling techniques and interviewed using an open and semi-structured questionnaire. We reported the primary (absolute) data as use reports (URs) with frequency citation (FC). The International Classification of Primary Care-2 (ICPC-2) was followed to categorize the therapeutic use of medicinal plants, and quantitative analysis was performed using the FC and informant consensus factor (ICF).

RESULTS

The present study explored and compiled a total of 3199 medicinal URs for 98 medicinal plant species to treat 132 ailment conditions under sixteen (16) ICPC-2 pathological groups. The highest URs (948) were noted for the digestive (D) group treated by 69 plant species, where the highest ICF value was measured for the social problem (Z) disease category (ICF: 1.00). Of the recorded medicinal plants, 17 were identified as true Mangrove (MNG), 24 as Mangrove Associates (MNA), and 57 as Non-Mangrove (NMG) species. Fabaceae (13 species) represented the leading family, followed by Lamiaceae and Compositae (5 species). Herbs (43%) have shown dominant life forms, and the leaves (41%) were frequently used plant parts. The most commonly cited preparation method was juice (24%), and the prevalent mode of administration was oral (62%). Azadirachta indica A. Juss. was the most widely used therapeutic plant species based on FC (39) values. The comparative literature review study reveals that the practices of 15 plants and their ethnomedicinal use by the Munda people are still entirely unexplored and newly reported in Bangladesh. Additionally, therapeutic use of 2 species, Brownlowia tersa (L.) Kosterm., and Dalbergia candenatensis (Dennst.) Prain has not been previously reported worldwide. In addition, 51 plant species (52%) of the total plants studied enlisted on the IUCN Red List of Threatened Species.

CONCLUSION

To our knowledge, this is the first ethnobotanical study on the Munda ethnic group in Bangladesh. This study indicates that Munda people still rely on medicinal plants for PHC and have a rich and varied traditional knowledge about the therapeutic use of plants. This study also warns of the high risk of the current availability status of plants in the study area. Therefore, this study calls for urgent steps to protect and conserve high-risk plants that can be done by taking both in-situ and ex-situ measures. In addition, further phytochemical and pharmacological investigations of the important medicinal plants cited in the study have been suggested.

Photosynthetic electron transport rate (ETR) in the littoral herb Launaea sarmentosa known as mole crab in Thailand

Launaea sarmentosa (Willd.) Sch. Bip ex Kunze (Asteracaeae) is a littoral sand dune herb found in the Indian Ocean region, used as a folk medicine and as a savory vegetable in Thailand. It is in the transition stage from a kitchen & cottage industry to a commercial proposition. Rapid light curves to measure the photosynthetic electron transport rate (ETR) were conducted on the plants over the course of daylight from 6:00 to 18:00 using a PAM fluorometer on plants grown under 50% (nominal) green horticultural and 20% black (nominal) shade cloth and in the open. Plants grown in the open were sun plants. E_opt (µmol photon m^-2 s^-1) decreased slightly under shade cloth (open air: 890 > green shade cloth, 778 > green shade cloth, 713). Launaea shows limited shade adaptation. ETR decreased under shade cloth on both a surface area and Chl a basis (µmol e^- g Chl a^-1 s^-1) [open air: 388 > (green shade cloth, 209 = black shade cloth, 263)]. Maximum non-photochemical quenching (NPQ_max) was significantly decreased under black shade cloth [(open air: 1.02 = green shade cloth, 0.969) > black shade cloth, 0.694]. ETR showed midday inhibition (9:00-15:00) when irradiance exceeded the E_opt of Launaea. Daily total photosynthetic electron transport was (mmol e^- m^-2 d^-1): open air, 1890 ± 157; green shade cloth, 1620 ± 203, black shade cloth, 1217 ± 143. Green shade cloth has no effect on total daily photosynthetic electron transport of Launaea but offers some protection from desiccation and excessive evapotranspiration. Waterlogging decreases ETR by about 40%. Launaea can be grown watered with brackish (½ seawater) water unlike many other vegetables. Launeae is a physiologically undemanding cottage industry/market garden crop suitable for sandy coastline fishing communities.

Assessment of pharmacological activities of Lygodium microphyllum Cav. leaves in the management of pain, inflammation, pyrexia, diarrhea, and helminths: In vivo, in vitro and in silico approaches

Lygodium microphyllum Cav. (Family: Lygodiaceae) is a perennial, snake fern and an invasive weed in Florida and also known as old world climbing fern. This study is intended to evaluate the antipyretic, analgesic, anti-inflammatory, antidiarrheal and anthelmintic activity of methanol extract of Lygodium microphyllum Cav. leaves (MELM) by in vivo, in vitro and in silico approaches. In addition, Biovia, PyRx autoDock Vina, UCSF Chimera have been applied to investigate the docking study in order to evaluate the binding interaction and an online tool was used to explore the ADME/T properties of selected bioactive compounds. In acetic acid induced writhing study, MELM inhibited 44.28% and 56.61% of writhes at 200 and 400 (mg/kg) respectively compared to standard drug Diclofenac-Na (10 mg/kg) (74.42% inhibition). In anti-inflammatory experiment by formalin triggered licking method, MELM caused significant (p < 0.05) inhibition of licking in both early phase (42.97%, 63.30%) and late phase (43.35%, 63.03%) at the doses of 200 and 400 mg/kg respectively, whereas reference drug Ibuprofen inhibited paw licking 77.18% in early phase and 76.86% in late phase. MELM also showed promising antipyretic potential where the maximum reduction of fever was produced by MELM 400 mg/kg whose fever lowering capacity is close to the prescribe drug Indomethacin 4 mg/kg, i.p. In Castor oil triggered diarrhea method, MELM delayed the onset time of diarrhea, continuous persistence of wet feces, and decreased the weight of wet feces remarkably. Defection inhibition was achieved 27.56% and 51.72%, for MELM 200 and at 400 (mg/kg) respectively while loperamide 2 (mg/kg) yields 55.17% inhibition of the diarrheal defecation. In anthelmintic bioassay, MELM took 5.83 ± 0.83 and 41.67 ± 1.78 min respectively for paralyzing and death compared to standard drug albendazole; (paralysis time 4.00 ± 0.73 min and death time 31,00 ± 1.71 min). Isoeleutherol, isoquercetin and quercetin were found prominent in molecular docking study and ADME/T analysis verified their drug likeliness. The research validates the moderate analgesic, anti-inflammatory, and remarkable antipyretic, antidiarrheal, anthelmintic activities of the plant extract which can be used an alternative source of novel therapeutics.

Effects of Launaea sarmentosa Extract on Lipopolysaccharide-Induced Inflammation via Suppression of NF-κB/MAPK Signaling and Nrf2 Activation

Launaea sarmentosa has been extensively used as a nutrient herb in traditional Vietnamese remedies for the treatment of various diseases, especially inflammatory diseases. However, no detailed research has been conducted examining the molecular mechanisms involved in the suppression of inflammatory response. Here, we studied the effects of L. sarmentosa methanol extract on lipopolysaccharide (LPS)-induced inflammation using RAW 264.7 macrophages. The extract demonstrated potent antioxidant activity owing to the presence of polyphenolic and flavonoid components. Pretreatment with the extract inhibited LPS-mediated secretion of nitric oxide, reactive oxygen species, and tumor necrosis factor-α as well as the expression of inflammatory cytokines. Furthermore, the activation of the nuclear factor-kappa B pathway and phosphoinositide-3-kinase/protein kinase B pathways was blocked by the extract by inhibiting Akt phosphorylation. Additionally, the mitogen-activated protein kinase pathway was suppressed, and endoplasmic reticulum stress was attenuated. Furthermore, the extract promoted the activity of nuclear factor erythroid-2-related factor 2 resulting in the up-regulation of heme oxygenase-1 pathway, leading to the suppression of oxidative stress and inflammatory response. Taken together, the results indicate that L. sarmentosa exhibits anti-inflammatory effects, and hence, can be further developed as a novel drug for the treatment of diseases associated with excessive inflammation.

Delta- and mu-opioid pathways are involved in the analgesic effect of Ocimum basilicum L in mice

ETHNOPHARMACOLOGICAL RELEVANCE

Ocimum basilicum L. is a perennial herb that has been used in traditional Asian Indian medicine for thousands of years as a natural anti-inflammatory, antibiotic, diuretic, and analgesic.

AIM OF THE STUDY

The present study was conducted to investigate the analgesic effects of basil essential oil (BEO) in inflammatory pain models and identify underlying mechanisms. We further investigated whether BEO affects physiological pain and motor coordination.

MATERIALS AND METHODS

The analgesic effects of BEO were assessed in various mouse experimental pain models using formalin, acetic acid, heat, and carrageenan as stimuli. BEO was administered by intraperitoneal injection or inhalation. The involvement of various pathways in the analgesic effect of BEO was assessed by pretreating mice with selective pharmacological inhibitors, administered intraperitoneally. Opioid pathways were tested using the κ-opioid antagonist 5'-guanidinonaltrindole (GNTI; 0.3 mg/kg), δ-opioid antagonist naltrindole (NTD; 5 mg/kg) and μ-opioid antagonist naloxone (NAL; 8 mg/kg); nitric oxide (NO) pathways were tested using the NO synthase inhibitor N-nitro l-arginine methyl ester (L-NAME; 37.5 mg/kg) and NO precursor L-arginine (L-Arg; 600 mg/kg); and K_ATP channel pathways were tested using the ATP-sensitive K⁺ channel blocker, glibenclamide-hippuric acid (GHA, 2 mg/kg). Potential effects of BEO on motor coordination were assessed using a rotarod test.

RESULTS

BEO exerted analgesic effects in all pain models. Notably, pretreatment with naltrindole, naloxone, or L-arginine significantly reduced the analgesic effects of BEO in the formalin test. BEO increased mean withdrawal latencies in a thermal plantar test at a high dose, but not at lower doses. BEO had no effect on motor coordination.

CONCLUSIONS

Our findings indicate that the analgesic effects of BEO are primarily mediated by delta- and mu-opioid pathways and further suggest that BEO has potential for development as an analgesic agent for the relief of inflammatory pain.

Antipyretic potential of dichloromethane leaf extract of Eucalyptus globulus (Labill) and Senna didymobotrya (Fresenius) in rats models

Introduction

Fever is managed using synthetic drugs such as aspirin, paracetamol among others. Synthetic drugs are associated with many side effects. Herbal medicines form alternative therapy since they possess fewer side effects and are readily available. This study aimed to determine antipyretic potential of DCM extracts of E. globulus and S. didymobotrya in Swiss albino rats.

Materials and methods

The plant leaves samples were obtained from Embu County, Kenya. Dichloromethane solvent was used to extract bioactive constituents from the plant samples. Three grams of DCM leaf extracts of Eucalyptus globulus (Labill) and Senna didymobotrya (Fresenius) samples were obtained and analyzed to determine quantitative phytochemical composition at ICIPE laboratory using GC-MS. Albino rats were used in the antipyretic activity study. Nine groups of five experimental animals were used in each test: Positive control, normal control, negative control and experimental (25, 50, 100, 150, 200 and 250 mg/kg body weight extracts) groups. Pyrexia was induced by injection of turpentine in albino rats intraperitoneally. One hour later, the pyretic animals received the leaf extracts at various dose levels, reference drug (aspirin100 mg/kg body) or the vehicle (DMSO).

Results

Results of antipyretic in vivo bioscreening revealed that E. globulus and S. didymobotrya possess potent antipyretic activity which was comparable to that of the reference drug aspirin. Both extracts exhibited highest antipyretic activity at a dose of 250 mg/kg bw. Results of the GC-MS revealed that these plants possess bio-compounds such as Terpinolene, Alpha-pinene, Borneol, Globulol and Terpineols that are associated with antipyretic activity.

Conclusions

In conclusion, this study revealed that these plants are endowed with bioactive compounds such as terpenoids, and flavonoids that possess antipyretic activity in rats.

Ethnopharmacology, Phytochemistry, and Global Distribution of Mangroves-A Comprehensive Review

Mangroves are ecologically important plants in marine habitats that occupy the coastlines of many countries. In addition to their key ecological importance, various parts of mangroves are widely used in folklore medicine and claimed to effectively manage a panoply of human pathologies. To date, no comprehensive attempt has been made to compile and critically analyze the published literature in light of its ethnopharmacological uses. This review aims to provide a comprehensive account of the morphological characteristics, ethnobotany, global distribution, taxonomy, ethnopharmacology, phytochemical profiles, and pharmacological activities of traditionally used mangroves. Out of 84 mangrove species, only 27 species were found to be traditionally used, however not all of them are pharmacologically validated. The most common pharmacological activities reported were antioxidant, antimicrobial, and antidiabetic properties. Mangroves traditionally reported against ulcers have not been extensively validated for possible pharmacological properties. Terpenoids, tannins, steroids, alkaloids, flavonoids, and saponins were the main classes of phytochemicals isolated from mangroves. Given that mangroves have huge potential for a wide array of medicinal products and drug discovery to prevent and treat many diseases, there is a dire need for careful investigations substantiated with accurate scientific and clinical evidence to ensure safety and efficient use of these plants and validate their pharmacological properties and toxicity.

An in vivo study of the pharmacological activities of a methanolic acetate fraction of Pistia stratiotes L.: An ethno-medicinal plant used in Bangladesh

BACKGROUND

The present study covered an assessment of methanolic acetate fractions of Pistia stratiotes, commonly known as water lettuce, for analgesic, anti-inflammatory, and CNS depressant activities.

METHODS

The methanol acetate fractions were extracted from Pistia stratiotes and administered to the experimental animals as 200 and 400 mg/kg doses to determine the effect on acetic acid-induced writhing and formalin-induced licking and biting, for the assessment of analgesic activity. The anti-inflammatory assay was done using the carrageenan-induced hind paw edema method, while assessment of CNS depressant activity was done using the open field and hole cross tests. The effects were compared to standard reference drugs.

RESULTS

At both doses (200 and 400 mg/kg body weight), the methanolic acetate extract of P. stratiotes showed significant analgesic action (P < 0.05) against acetic acid-induced writhing. The extract was also found to give significant protection against licking and biting at both doses. The methanolic acetate extract of P. stratiotes showed a significant (P < 0.05) anti-inflammatory effect from 0 minutes up to 3 hours in the carrageenan-induced paw edema test. In the CNS depressant assay, the methanolic acetate extract showed significant (P < 0.05) depressant activity at both doses from 30 to 120 minutes in both the hole cross and open field tests.

CONCLUSION

Thus we can conclude that P. stratiotes extracts have significant analgesic, anti-inflammatory, and CNS depressant activity, compared to standard compounds, in an animal model.

Ascertainment of pharmacological activities of Allamanda neriifolia Hook and Aegialitis rotundifolia Roxb used in Bangladesh: An in vitro study

The present study was cherished to investigate in vitro thrombolytic, membrane stabilizing and antibacterial activities of Allamanda neriifolia and Aegialitis rotundifolia. Different types methanolic extracts of these two medicinal plants were tested for determining membrane stabilizing activity at a hypotonic solution and heat induce condition by comparing with reference standard acetyl salicylic acid (0.10 mg/mL), where thrombolytic activity assessment was done by employing Streptokinase as standard drug. Finally, antibacterial activity was performed against Staphylococcus aureus as a Gram-positive (+ve) and Salmonella typhi, Escherichia coli and Pseudomonas aeruginosa as Gram negative (−ve) bacteria by using disc diffusion method. In case of membrane stabilizing studies, crude methanolic extracts of A. neriifolia at 10 mg/ml concentration, more importantly, showed 45.80% & 23.52% whereas 10 mg/ml concentration of A. rotundifolia more significantly (p < 0.01) produced 38.40% and 27.04% inhibition of hemolysis for both experimental conditions. Dose-dependently increased activity was found in the thrombolytic study where 10 mg/ml concentration of both A. neriifolia and A. rotundifolia more significantly (p < 0.01) showed 41.91% and 32.76% lysis of clot respectively by in vitro clot lysis assay method. Crude methanolic extracts of A. rotundifolia did not show any suitable antibacterial property against the test bacteria. However, the gram positive (+ve) bacteria also seemed resistant against A. neriifolia extract but this crude methanolic extracts was found to generate moderate antibacterial action against gram-negative (−ve) bacteria. The obtained results confirmed the presence of thrombolytic, membrane stabilizing activity for both plant extract along with moderate antibacterial activity for A. neriifolia.