Brine Shrimp Lethality Assay Research Articles

Antibacterial Activity against Clinical Isolates of <i>Salmonella enterica</i> Serovar Paratyphi and Brine Shrimp Lethality Assay of <i>Trichilia megalantha</i>Harms and <i>Trichilia welwitschii</i> C. DC

Increasing resistance of typhoidal Salmonella enterica to conventional antibiotics has caused more cases of typhoid, therapeutic failure, morbidity and mortality; creating the need to search for new and effective antimicrobial agents from medicinal plants. The present study aimed to detect antisalmonella activity and cytotoxicity (safety) status of the stem bark and leaves of two Nigerian medicinal plants, Trichilia megalantha and Trichilia welwitschii. Nine clinical isolates of Salmonella paratyphi, whose antibiogram were determined by Kirby-Bauer disc diffusion method were used. Antibacterial activity, minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of the extracts on the clinical isolates were done by agar cup diffusion and agar dilution methods, respectively. Acute toxicity of the extracts was determined using brine shrimp lethality assay (BSLA). All the nine isolates of Salmonella paratyphi were resistant to β-lactam antibiotics (augmentin, cefuroxime, ceftazidime and ampicillin) but susceptible to fluoroquinolones (ciprofloxacin, ofloxacin), nitrofurantoin and gentamicin. The crude extracts of the two plants elicited activity against the nine clinical isolates with the bark extracts being more active than the leaf extracts. T. welwitschii was slightly less active than T. megalantha. The MIC and MBC ranged 1.25 - 5.0 mg/ ml and 2.5 - 10 mg/ml, respectively for the plants. The antisalmonella activity of methanolic extracts of both plants were found to be less than that of ciprofloxacin and ofloxacin. With modal cytotoxicity values of 400 - 500 μg/ml, the plant parts were considered nontoxic. Therefore, T. megalantha and T. welwitschii could provide a potential source of antibacterial agent(s) for the treatment of Salmonella paratyphoid infections.
 Keywords: Trichilia megalantha; Trichilia welwitschii, antisalmonella; cytotoxicity; Salmonella paratyphi

Cytotoxicity of Iron Nanoparticles Synthesized Using Dried Ginger

Zingiber officinale (also called ginger) is commonly used for traditional treatment of various diseases and for culinary purposes. This plant species is a herbaceous and develops yearly pseudostems around one meter tall bearing limited leaf cutting edges. The synthesis of metal nanoparticles and nanocomposites is an emerging area of research and exploration in the field of material science for their unique size and shape and have reliant features that are different from the regular bulk structure. The aim of the present study was to synthesize iron nanoparticles using dried ginger and evaluate their cytotoxic effects against brine shrimp. The nanoparticles were synthesized using dried ginger and characterized by UV-vis spectroscopy. The cytotoxicity assessment was carried out using brine shrimp lethality assay. The iron nanoparticles did not show any cytotoxicity to the brine shrimp. This eco-friendly synthesis of iron nanoparticles from dried ginger has proved to be convenient, inexpensive and can be safely used in wide range of medicine and dental fields.

Bioactivity evaluation of commercial root samples of Hemidesmus indicus (L.) R.Br.

Four commercial root samples (CS1, CS2, CS3 and CS4) of Hemidesmus indicus alongside an authentic sample (HI) were evaluated following antibacterial potential, cytototoxicity and DPPH free radical scavenging activity assay. The inhibition zones produced by commercial samples ranged between 9.5 to 13.5 mm against the tested bacteria in antibacterial sensitivity test. HI produced highest inhibition zone recorded as 20.63 mm against Staphylococcus aureus followed by 17.4 mm against Bacillus subtilis at 150 μg/ml concentration. HI also showed highest cytotoxicity with LC50 value of 1.726 mg/ml, 4.754 mg/ml and 13.247 mg/ml after 6 hours, 12 hours and 24 hours respectively in brine shrimp lethality assay. Sample CS1 and CS2 showed less cytotoxicity compared to CS3 and CS4. Depending on the concentration of extracts, the DPPH free radical scavenging activities of commercial samples were in close proximity with HI. The total phenolic content in HI was 54.52 mg/ml while in four commercial sample, it ranged between 52.28 to 75.37 mg/ml gallic acid equivalent (GAE) per 100 mg extract.
 Jahangirnagar University J. Biol. Sci. 8(2): 61-69, 2019 (December)

Plant description, phytochemical constituents and bioactivities of Syzygium genus: A review

AbstractThis article attempts to report native growth, plant description, phytochemical constituents and bioactivities of Syzygium aqueum, S. aromaticum, S. cumini, S. guineense and S. samarangense. Those are the large public species in the Syzygium genus and some of them have been used as traditional medicines. Different parts (leaves, seeds, fruits, barks, stem barks and flower buds) of each species plant are rich in phytochemical constituents such as flavonoids, terpenoids, tannins, glycosides and phenolics. Antioxidant, antidiabetic, anticancer, toxicity, antimicrobial, anti-inflammatory and anthelmintic activities are reported in various extracts (methanol, ethanol and aqueous) from different parts of Syzygium sp. The bioactivities were studied by using 1,1-diphenyl-2-picrylhydrazyl and ferric reducing antioxidant power assays for antioxidant, 5-(3-carboxymethoxyphenyl)-2-(4,5-dimethyl-thiazoly)-3-(4-sulfophenyl) tetrazolium and 3-(4,5-dimethylthiazol-2-yl)-2-5-diphenyltetrazolium bromide assays for anticancer, α-glucosidase and α-amylase inhibition assays for antidiabetic, agar well diffusion method for antimicrobial and brine shrimp lethality assay for toxicity. Moreover, this review shows that phytochemical constituents of each species significantly presented various bioactivities. Therefore, this review suggests that there is great potential for obtaining the lead drug from these species.

In vitro bactericidal, antidiabetic, cytotoxic, anticoagulant, and hemolytic effect of green-synthesized silver nanoparticles using Allium sativum clove extract incubated at various temperatures

AbstractThe current research aimed to evaluatein vitrobiological activities of green-synthesized silver nanoparticles using theAllium sativumclove extract. The stability of green-synthesized silver nanoparticles was evaluated via storage at 4°C, room temperature (37°C), and calcined at 300°C, 500°C, and 700°C. The antibacterial effect was evaluated using agar well, spread plate, biofilm reduction, and cell proliferation inhibition assays. The cytotoxic and antidiabetic effects were determined via brine shrimp lethality, protein kinase inhibition, and α-amylase inhibition assays. DPPH scavenging, iron-chelating, anticoagulant, and hemolytic effects were evaluated. The highest inhibition ofKlebsiella pneumoniaewas observed when freshly prepared, calcined (300°C), and stored nanoparticles (4°C and 37°C) were applied (9.66, 9.55, 7.33, and 6.65 mm) against freshly prepared and calcined at 700°C which showed the highest inhibition ofPseudomonas aeruginosa(8.55 and 7.66 mm). Cell viability assay, biofilm reduction assay, and spread plate method showed a significant antibacterial effect of freshly prepared silver nanoparticles. Freshly prepared and calcined nanoparticles at 300°C and 500°C possessed strong antioxidant and iron-chelating activity. Among all the synthesized silver nanoparticles, freshly prepared and calcined nanoparticles (300°C and 500°C) increases the prothrombin time. Silver nanoparticles possessed significant anticoagulant properties and less toxic at least concentration toward human RBCs. In brine shrimp lethality assay, freshly prepared nanoparticles showed a stronger toxic effect and caused high mortality of larvae. Protein kinase inhibition assay revealed that freshly prepared nanoparticles had the highest zone of inhibition (18.0 mm) at 50 µg/disc. Green-synthesized nanoparticles would be used as potential therapeutic agents to overcome both infectious and noninfectious diseases.

Evaluation of antimicrobial, antioxidant and cytotoxic properties of bioactive compounds produced from endophytic fungi of Himalayan yew ( Taxus wallichiana) in Nepal.

Background: Endophytic fungi are largely underexplored in the discovery of natural bioactive products though being rich sources of novel compounds with promising pharmaceutical potential. In this study, Taxus wallichiana, which has huge medicinal value, was investigated for its endophytic diversity and capability to produce bioactive secondary metabolites by analyzing antioxidant, antimicrobial and cytotoxic properties. Methods: The endophytes were identified by ITS-PCR using genomic DNA samples. The secondary metabolites were extracted by solvent extraction method using ethyl acetate. The antioxidant activity was analyzed by Thin Layer Chromatography, Total Phenol Content (TPC), Total Flavonoid Content (TFC) and DPPH assay, and the antimicrobial activity was analyzed by agar-well diffusion method. Brine shrimp lethality assay was used to analyze the cytotoxicity of the fungal extracts. Results: Out of 16 different Taxus trees sampled from different locations of Dhorpatan, 13 distinctive endophytic fungi were isolated and grouped into 9 different genera: Bjerkandera, Trichoderma, Preussia, Botrytis, Arthrinium, Alternaria, Cladosporium, Sporormiella and Daldinia. The ethyl acetate extracts isolated from three endophytic fungi: Alternaria alternata, Cladosporium cladosporioides and Alternaria brassicae showed significant TPC values of 204±6.144, 312.3±2.147 and 152.7±4.958µg GAE/mg of dry extract, respectively, and TFC values of 177.9±2.911, 644.1±4.202 and 96.38±3.851µg RE/mg of dry extract, respectively. Furthermore, these three extracts showed a dose dependent radical scavenging activity with IC 50 concentration of 22.85, 22.15 and 23.001 µg/ml, respectively. The extracts of C. cladosporioides and A. brassicae also showed promising antimicrobial activity against Escherichia coli, Staphylococcus aureus and Bacillus subtilis with a minimum inhibitory concentration of 250μg/ml for all bacteria. Both the samples showed cytotoxic property against shrimp nauplii with LC 50 of 104.2 and 125.9µg/ml, respectively. Conclusions: The crude fungal extracts obtained from endophytes: A. alternata, C. cladosporioides and A. brassicae upon purification and further identification of the bioactive compounds can be a fascinating source for novel pharmaceutical agents.

English

English

Evaluation of antimicrobial, antioxidant and cytotoxic properties of bioactive compounds produced from endophytic fungi of Himalayan yew ( Taxus wallichiana) in Nepal

Background: Endophytic fungi are largely underexplored in the discovery of natural bioactive products though being rich sources of novel compounds with promising pharmaceutical potential. In this study, Taxus wallichiana, which has huge medicinal value, was investigated for its endophytic diversity and capability to produce bioactive secondary metabolites by analyzing antioxidant, antimicrobial and cytotoxic properties. Methods: The endophytes were identified by ITS-PCR using genomic DNA samples. The secondary metabolites were extracted by solvent extraction method using ethyl acetate. The antioxidant activity was analyzed by Thin Layer Chromatography, Total Phenol Content (TPC), Total Flavonoid Content (TFC) and DPPH assay, and the antimicrobial activity was analyzed by agar-well diffusion method. Brine shrimp lethality assay was used to analyze the cytotoxicity of the fungal extracts. Results: Out of 16 different Taxus trees sampled from different locations of Dhorpatan, 13 distinctive endophytic fungi were isolated and grouped into 9 different genera: Bjerkandera, Trichoderma, Preussia, Botrytis, Arthrinium, Alternaria, Cladosporium, Sporormiella and Daldinia. The ethyl acetate extracts isolated from three endophytic fungi: Alternaria alternata, Cladosporium cladosporioides and Alternaria brassicae showed significant TPC values of 204±6.144, 312.3±2.147 and 152.7±4.958µg GAE/mg of dry extract, respectively, and TFC values of 177.9±2.911, 644.1±4.202 and 96.38±3.851µg RE/mg of dry extract, respectively. Furthermore, these three extracts showed a dose dependent radical scavenging activity with IC 50 concentration of 22.85, 22.15 and 23.001 µg/ml, respectively. The extracts of C. cladosporioides and A. brassicae also showed promising antimicrobial activity against Escherichia coli, Staphylococcus aureus and Bacillus subtilis with a minimum inhibitory concentration of 250μg/ml for all bacteria. Both the samples showed cytotoxic property against shrimp nauplii with LC 50 of 104.2 and 125.9µg/ml, respectively. Conclusions: The crude fungal extracts obtained from endophytes: A. alternata, C. cladosporioides and A. brassicae upon purification and further identification of the bioactive compounds can be a fascinating source for novel pharmaceutical agents.

Medicinal plant: Dye combinations – Impact on antimicrobial potency and toxicity

Indigenous medicinal plants have been shown to be effective in treating skin conditions in southern Africa. In the past, antimicrobial dyes have also been used to treat dermatological infections with great success. The aim of this study was to investigate the antimicrobial properties of a combination of selected southern African medicinal plant species and dyes against infectious dermatological pathogens. Medicinal plants, dyes and their combinations were antimicrobially explored, with particular interest towards ascertaining the inhibitory activity via minimum inhibitory concentration (MIC) assays and cidal activities via minimum bactericidal/fungicidal (MBC or MFC) assays. The studies were conducted against various strains (reference, clinical and resistant) of Staphylococcus aureus, Pseudomonas aeruginosa and Candida albicans. The toxicity of the most active plants, dyes and combinations were also investigated employing the brine shrimp lethality assay. Seven of the tested plants, exhibited moderate antimicrobial activities (>160 - ≤ 1000 µg/ml) against various strains of S. aureus, P. aeruginosa and C. albicans. The best observed antibacterial activities were from Aristea ecklonii roots (130 µg/ml) and Calodedrum capense (125 µg/ml) against the reference strain of S. aureus ATCC 25923. Most of the selected dyes exhibited good antimicrobial activities with the best activity observed for malachite green (0.5 µg/ml) against S. aureus (clinical and methicillin resistant strain ATCC 43360) and C. albicans (resistant strain). The combination of the dye malachite green with selected plant species demonstrated the most enhanced synergy with ΣFIC values as low as 1.0 × 10−6. Two plant species (A. ecklonii leaves and roots as well as C. capense) demonstrated toxicity (LC50 values 166 µg/ml, 99 µg/ml and 1005 µg/ml, respectively) and most of the dyes exhibited some toxicity. In combination the toxicity was reduced. This study highlights the critical role that plants can play in bringing back previously neglected therapies (dyes) which have the potential, when combined, to combat skin infections and thus be considered for future possible treatments.

Molecular Docking, Antioxidant, Anticancer and Antileishmanial Effects of Newly Synthesized Quinoline Derivatives.

Due to the pressing need and adverse effects associated with the available anti-cancer agents, an attempt was made to develop the new anti-cancer agents with better activity and lesser adverse effects. Synthetic approaches based on chemical modification of quinoline derivatives have been undertaken with the aim of improving anti-cancer agents' safety profile. In the present study, quinoline derivatives 6-hydroxy-2-(4-methoxyphenyl) quinoline-4-carboxylic acid (M1) and 2-(4-chlorophenyl)-6-hydroxyquinoline-4-carboxylic acid (M3) were synthesized by the reaction of aldehyde and pyruvic acid. The complete reaction was indicated by thin-layer chromatography. Newly synthesized M1and M3were tested for in silico and in vitro studies. M1 and M3 were docked against selected targets. Both the test compounds showed good affinity against all targets except the p300\CBP-associated factor target as there was no H-bond formed by M1. IC50 values of M1 and M3 against 1, 1-diphenyl-picrylhydrazyl free radical scavenging activity were 562 and 136.56ng/mL, respectively. In brine shrimp lethality assay, M1 and M3 showed IC50 value of 81.98 and 139.2ng/mL, respectively. IC50 values recorded for M1 and M3 in tumor inhibition activity were 129 and 219μg/mL, respectively. M1 and M3 exhibited concentration-dependent anti-cancer effects against human cell lines of hepatocellular carcinoma (HepG2) and colon cancer (HCT-116). Against HepG2 cells, M1 and M3 exhibited IC50 of 88.6 and 43.62μg/mL, respectively. M1 and M3 utilized against HCT-116 cell lines possessed IC50 values of 62.5 and 15.3μg/mL. M1 and M3 also showed an anti-leishmanial effect with IC50 values of 336.64 and 530.142μg/mL, respectively. From the results of pharmacological studies, we conclude that the newly synthesized compound showed enhanced anti-oxidant, anti-cancer and anti-leishmanial profile with good yield.

COMPARISON STUDY OF ANTIOXIDANT, ANTIMICROBIAL AND CYTOTOXIC PROPERTIES OF SECONDARY METABOLITE AND PROTEIN EXTRACTS FROM CLINACANTHUS NUTANS

Objective: The present study aims to evaluate the antioxidant, antimicrobial and cytotoxic properties of the secondary metabolites and proteins extracted from Clinacanthus nutans.
 Methods: Methanol (ME) and acetone (AC) and also protein (PE) extracts were obtained from Clinacanthus nutans. Antioxidant activity of sample extracts was examined by using 1,1-Diphenyl-2-Picrydyl Hydrazyl (DPPH) assay and antimicrobial activity was examined by using the agar diffusion method against Bacillus subtilis, Bacillus cereus, Streptococcus pyrogenes, Escherichia coli, and Pseudomonas aeroginosa bacterial strain. The cytotoxic potential was determined by brine shrimp lethality assay.
 Results: Methanol extract (ME) demonstrated to have the highest antioxidant activity with IC50 value of 98.84 μg/ml, followed by acetone extract (AE) with IC50 value of 134.83µg/ml, and protein extract (PE) with IC50 value of 353.49 µg/ml. Among all of the sample extracts, only methanol crude extracts (ME) displayed moderate inhibition against Gram-positive B. cereus (7.33±1.15 mm) and S. pyrogenes (8.67±0.57 mm) at concentration of 100 mg/ml, while both acetone (AE) and protein (PE) extracts had no activity against all tested microorganisms. All extracts from methanol (ME), acetone (AE) and protein (PE) exhibited significant cytotoxic activity against brine shrimps at LC50 7.2 μg/ml, 1.42 μg/ml and 70.6 μg/ml respectively.
 Conclusion: These data proved that methanol extract from the leaves of Clinacanthus nutans is the most potent among all samples tested and has the potential to be developed as an antioxidant, antimicrobial and cytotoxic agents. Whilst, acetone and protein crude extracts have potent antioxidant and cytotoxicity activities.

Comparative study of two Eucalyptus species from Algeria: chemical composition, toxicity and acaricidal effect on Varroa destructor

Abstract Varroa destructor is an external parasitic mite that is a serious pest of honeybees and has caused severe losses of colonies worldwide. One of the feasible alternative treatments being used for their control is the application of essential oils, which are generally inexpensive and most pose few health risks. The investigation was designed to determine the chemical composition, toxicity and acaricidal effects of Eucalyptus amygdalina leaf essential oil (EaEO) grown in Algeria and to compare its activity on Varroa destructor with that of Eucalyptus globulus from the same region. Fresh leaves of E. amygdalina (Ea) by steam distillation yielded 0.77% (v/w), and investigation of the oil on GC/MS resulted in the identification of 35 compounds, with 1.8-cineole (35.78%) as most abundant constituent. Other notable compounds include spathulenol (12.58%), camphene (7.73%), α-pinene (4.38%), valencene (2.64%), while 2-carene and ledol (1.45%) were also among the constituents identified. The acaricidal features of the essential oil was evaluated using bee hives infected by Varroa destructor, and a significant effect of oil application was observed (p < 0.05). Cytotoxic effect was assayed using the brine shrimp lethality assay, Probit’s analysis of the result revealed an LC50 value of 116.06 μg/mL. Essential oil of E. amygdalina (EaEO) has potential acaricidal effect on Varroa destructor, but this effect is less important than the one recorded by E. globulus. Further studies are needed to determine the active component responsible for this effect.

Cytotoxic Effect and Antimicrobial Activity of Chitosan Nanoparticles and Hafnium Metal Based Composite: Two Sides of the Same Coin- An In vitro Study

Chitosan (CTS) is a biocompatible polymer that has been widely researched for tissue engineering purposes. It has demonstrated a significant role in bone tissue engineering in the last two decades. Being a natural polymer obtained from chitin, a major component of crustacean exoskeleton, it has varied uses. Lately, attention has been given to chitosan composite materials due to its minimal foreign body reactions, antibacterial nature, biocompatibility, biodegradability, and the ability to be molded into various shapes and forms. It can be used as porous structures, suitable for cell ingrowth and osteoconduction. The aim of this research was to assess the biocompatibility of a chitosan nanoparticle and hafnium metal-based composite and project its use for bone tissue engineering. In the present study, we have prepared chitosan nanoparticles and their based hafnium composite and it was analyzed for its cytotoxic effect using brine shrimp lethality assay and antimicrobial activity using the disc diffusion method. There was a significant difference between the concentrations used (p<0.01), when One way ANOVA statistical analysis was performed. The current study substantiates the antimicrobial activity and highlights the possible cytotoxicity of the CTS and hafnium composite.

Cytotoxicity and Antimicrobial Activity of Chromium Picolinate Mediated Zinc Oxide Nanoparticle

Aim: To study the chromium picolinate mediated with zinc oxide nanoparticle and its cytotoxicity and antimicrobial activity
 Introduction: Chromium can alleviate glucose intolerance and insulin resistance and it is involved in the metabolism of glucose, lipid, protein, and nucleic acid .Chromium picolinate [CrPic], also named as picolinic acid chromium and several studies have proved that CrPic, as the source of Chromium, can alleviate the high level of blood glucose, blood lipid, insulin, and cholesterol in the patients with metabolic syndrome and zinc oxide [ZnO] has also gained momentum due to their unique properties in the process of nanotechnology. Chromium picolinate works together with insulin that produced by the pancreas to metabolize carbohydrates. It's made by combining chromium with picolinic acid. The acid helps the body absorb chromium. Randomized controlled trials have failed to demonstrate a link between chromium supplementation and the prevention or treatment of type 2 diabetes or impaired glucose tolerance. Chromium supplementation of young men and women does not promote muscle accretion, fat loss, or gains in strength. Physically active individuals with concerns about meeting guidelines for nutrient intake should be counseled to select and consume foods with high nutrient densities rather than to rely on nutritional supplements.
 Materials and Methods: Chromium picolinate mediated with ZnO nanoparticles were evaluated for its antibacterial activity and cytotoxicity potential using brine shrimp lethality assay.
 Results: Chromium picolinate mediated zinc oxide nanoparticles show good results in antimicrobial activity as well as in cytotoxicity.
 Conclusion: Chromium picolinate mediated Zn nanoparticles is an efficient antibacterial and a potential cytotoxicity agent.

Cassia oleoresin Mediated Synthesis of Magnesium Oxide Nanoparticles and Brine Shrimp Lethality Assay

Cassia oleoresin is an extract isolated from dried barks of Cinnamomum cassia Blume (family Lauracea). The plant has been reported to have anti-diabetic, anti-oxidant, anti-hypertriglyceridemic effect, mainly due to its phytochemical constituents such as phenolic and volatile compounds. Cinnamon also helps in arthritis, fibromyalgia and psoriasis. The aim of this study was to prepare magnesium oxide nanoparticles using Cassia oleoresin and to evaluate the cytotoxic effect on Brine shrimp. The magnesium oxide nanoparticle was prepared from magnesium chloride and Cassia oleoresin and was confirmed by UV- Visible Spectroscopy and morphology was confirmed by TEM. Brine shrimps lethality bioassay was carried out to investigate the cytotoxicity of Cassia oleoresin mediated magnesium oxide nanoparticles. Ten brine shrimp nauplii were placed in each well of the Eliza plate and filled with 5 µL ,10 µL ,15 µL ,20 µL ,25 µL of Cassia oleoresin mediated magnesium oxide nanoparticles After 24 hours of incubation, the wells were observed and the number of surviving brine shrimp nauplii were counted to assess the cytotoxicity. The UV -Visible spectroscopy showed a peak at 400 peak and TEM analysis showed a particle size of 70 nm. After 24 hours incubation of the brine shrimps in the nanoparticle solution, all 10 brine shrimps survived in 5µL and 10 µL concentrations. 3 brine shrimps nauplii survived in 15µL conc. 1 brine shrimp nauplii survived in 20µL and 25µL concentrations each. Within the limits of this study it can be concluded that at low concentrations the prepared nanoparticle was safe and may be used for biomedical application.

Cytotoxicity of the Most Active Fraction of the Seeds of Swietenia macrophylla using Human Breast Cancer MCF-7 Cells

Ethyl acetate fraction from Swietenia macrophylla was reported to have toxicity against the larvae of Artemia salina shrimp larvae. However, there areno reports aboutS. macrophylla, which can inhibit human breast cancer cells MCF-7. Therefore, this study aims to evaluate S. macrophyllaextract's cytotoxicity using human breast cancer MCF-7 cells assay, followed by confirmation of its toxicity using brine shrimp lethality assay. The most active fraction obtained from the ethyl acetate extract of S. macrophylla showed 76.49% inhibition at 50 µg/mL (IC50=34.11 µg/mL). At the same time, the most active fraction may contain a mixture of limonoid compounds after LCMS analysis. The most active fraction obtained from ethyl acetate extract of S. macrophylla showed 76.49%

Antimicrobial activity and toxicity of extracts from the bark and leaves of South African indigenous Meliaceae against selected pathogens

Species of the family Meliaceae in traditional medicine are well documented. This study evaluated the antimicrobial efficacy and toxicity of aqueous, methanolic and dichloromethane leaf and bark extracts of South African Meliaceae against selected pathogens. The species sampled represent four of the seven indigenous genera and seven of the 14 indigenous species. Antimicrobial activity was evaluated using the micro-plate dilution assay and the toxicity potential was determined using the brine shrimp lethality assay. About 69% of the extracts investigated showed moderate (0.25— 0.50 mg/ml) activities against the oral pathogens (Streptococcus mutans ATCC 25,175 and Fusobacterium nucleatum ATCC 25,586) tested. Pseudomonas aeruginosa and S. mutans was recorded as the most susceptible pathogens to the extracts. The antimicrobial activity of the extracts from Ekebergia pterophylla, Nymania capensis and Turraea obtusifolia (here documented for the first time) demonstrated varied activity depending on the pathogen. The aqueous extracts showed no antimicrobial activity with some exceptions against Streptococcus mutans (ATCC 25,175), where Ekebergia capensis and Trichilia dregeana exhibited noteworthy activity (0.13 mg/ml). In the brine shrimp assay, all DCM extracts of the studied parts of the plant species demonstrated minimal to no toxicity levels. The results obtained have lent credence to folkloric usage of some of the South African species of Meliaceae for anti-infective purposes including traditional uses against oral pathogens.

Antioxidant, Anti-inflammatory, Cytotoxic and Analgesic Activities of Sensevieria trifasciata

Sansevieria trifasciata is a common perennial ornamental plant which freely grows and widely found in homes, parks, and woodlands. Traditionally, this plant has been used against acne, allergy, helminths and fungal infections. In the present study, the ethanolic extract of leaves of Sansevieria trifasciata (STET) has been used to study the phytoconstituents and several bioactivities. In vitro antioxidant activity of STET has been determined by DPPH scavenging assay and measuring the total tannins and phenolic contents. Anti-inflammatory activity has been evaluated by hypotonic solution and heat induced hemolysis. Moreover, cytotoxic and analgesic activities have also been evaluated by brine shrimp lethality assay and acetic acid induced writhing inhibition method, respectively. STET confirmed the presence of reducing sugar, combined reducing sugar, tannins, flavonoids, glycosides, proteins and steroids. In DPPH scavenging assay, STET revealed the IC50 value 2.19 μg/ml whereas the standard showed 1.39 μg/ml. In addition, the total tannins and total phenolic contents were found to be 10.78 mg and 31.99 mg GAE/g of dried plant extract, respectively. In hypotonic solution induced hemolysis test, the plant extract exhibited 39.27, 37.04 and 33.19 % inhibition at 0.5, 1.0 and 2.0 mg/ml concentration where the reference standard displayed 30.57 % inhibition. In heat-induced hemolysis, the STET also displayed 34.25 % inhibition of hemolysis at 1 mg/ml. Furthermore, in analgesic and cytotoxic activity tests, STET showed potential activities in a dose dependent manner. The results of the present studies suggest that STET has antioxidant, anti-inflammatory, cytotoxic and analgesic activities. Bangladesh Pharmaceutical Journal 23(2): 195-200, 2020

Artemia species: An Important Tool to Screen General Toxicity Samples.

Medicinal plants are a good source of novel therapeutic drugs, due to the phytochemicals present. Artemia, commonly known as brine shrimp, is a tiny halophilic invertebrate belonging to class Crustacean, which plays an important role in saline aquatic and marine eco-systems. Besides its usage in aquaculture, it is also highly valued for its application in toxicity detection and it is used in areas such as Ecology, Physiology, Ecotoxicology, Aquaculture and Genetics. Furthermore, Artemia based lethality assay (brine shrimp lethality assay, BSLA) is rapid, convenient and low cost. Presently, brine shrimp lethality assays are enormously employed in research and applied toxicology. It has been used in the study of natural products as a preliminary toxicity assay to screen a large number of extracts and compounds for drug discovery in medicinal plants. The aim of this review paper is to collect, organize, select and discuss the existing knowledge about the different uses of Artemia salina as a bench-top bioassay for the discovery and purification of bioactive natural products.

Chemical constituent with cytotoxicity from Sterculia diversifolia

One new coumarin (stercularin), along with eleven known compounds, was isolated for the first time from ethyl acetate fraction of Sterculia diversifolia. The structures of isolated compounds were characterized by spectroscopic techniques such as EIMS, 1H-NMR and 13C-NMR. Compound 1 showed significant cytotoxicity by brine shrimp lethality assay (LD50: 8.00 μg/ml) and PC-3 cell lines protocol (IC50: 3.92 ± 0.20 μg/ml), respectively.