Artemia Salina Assay Research Articles

Morphological, Toxicological, and Biochemical Characterization of Two Species of Gambierdiscus from Bahía de La Paz, Gulf of California.

We describe five new isolates of two Gambierdiscus species from Bahía de La Paz in the southern Gulf of California. Batch cultures of Gambierdiscus were established for morphological characterization using light microscopy (LM) and scanning electron microscopy (SEM). Pigment and amino acid profiles were also analyzed using high-performance liquid chromatography (HPLC-UV and HPLC-DAD). Finally, toxicity (CTX-like and MTX-like activity) was evaluated using the Artemia salina assay (ARTOX), mouse assay (MBA), marine fish assay (MFA), and fluorescent receptor binding assay (fRBA). These strains were identified as Gambierdiscus cf. caribaeus and Gambierdiscus cf. carpenteri. Toxicity for CTX-like and MTX-like activity was confirmed in all evaluated clones. Seven pigments were detected, with chlorophyll a, pyridine, Chl2, and diadinoxanthin being particularly noteworthy. For the first time, a screening of the amino acid profile of Gambierdiscus from the Pacific Ocean was conducted, which showed 14 amino acids for all strains except histidine, which was only present in G. cf. caribeaus. We report the presence of Gambierdiscus and Fukuyoa species in the Mexican Pacific, where ciguatera fish poisoning (CFP) cases have occurred.

Controlled dual activity of an organometallic antibiotic through micelle formulation

Sodium Lauryl Sulphate (SLS) and Cetyltrimethylammonium bromide (CTAB) were employed to create micelles (SLS@CIPTIN and CTAB@CIPTIN) of the organometallic antibiotic Ph2Sn(CIP)2 (CIPTIN) (where HCIP= ciprofloxacin). The characterization of the micelles was conducted in the solid-state using melting point, Attenuated Total Reflectance-Fourier Transform Infra-Red (ATR-FTIR), 119Sn Mössbauer and X-ray Fluorescence (XRF) spectroscopies, and Thermogravimetry/Differential Thermal Analysis (TG-DTA), while in solution, by Ultra violet-Visible (UV–Vis) and Nucleus Magnetic Resonance (1HNMR ) spectroscopic techniques were employed. The compounds were tested for their antiproliferative activity against human breast adenocarcinoma cells: MCF-7 (hormone depended (HD)) and MDA-MB-231 (hormone independent (HI)). The in vitro and in vivo non-genotoxicity was confirmed with micronucleus (MN) and Artemia salina assay. The antiproliferative mechanism of action of SLS@CIPTIN and CTAB@CIPTIN was studied by cell morphology and cell cycle arrest. The antibacterial activity was evaluated using Minimum Inhibitory Concentration (MIC), Minimum Bactericidal Concentration (MBC) and Inhibition Zones (IZ) against Minimum Bactericidal Concentration (MBC) against Gram-negative strains P. aeruginosa, E. coli, as well as Gram-positive strains S. epidermidis and S. aureus. The results indicate that both the investigated CIPTIN and its supramolecular assembly (SLS@CIPTIN) exhibit activity. Therefore, the encapsulation of antimicrobial compounds can indeed be regarded as an attractive strategy for the development of new dual-active agents. These agents offer concurrent anticancer and antibacterial attributes without inducing toxicity.

Evaluation of cellular viability in chitosan/L-arginine hydrogels.

There is a lack of studies evaluating the toxicity of nitric oxide (NO) precursors in chitosan/L-arginine hydrogels and their topical administration. However, clarifying the characteristics of these elements is essential for their possible use in non-surgical techniques of tooth movement acceleration. Such characteristics include interaction with different cell types, metabolism and drug safety. This in vitro study aimed to assess the cytotoxicity of chitosan hydrogels on human HeLa cells using different concentrations of L-arginine. The hydrogels were synthesized in a materials engineering laboratory, with a controlled environment, using 4 different L-arginine concentrations of 0%, 10%, 15%, and 20%. Once the hydrogels were prepared, their physical and chemical properties were characterized, and viability analysis was performed using 2 different methods, including a 48-h assay with Artemia salina nauplii and a 24-h cell culture with human HeLa cells followed by a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) proliferation assay. Data analysis was performed using a Mann-Whitney U test to evaluate positive and negative controls in the cell culture, with a significance level of 0.01. A Wilcoxon paired test contrasted the 24-h compared to 48-h Artemia salina assays, with a Kruskal-Wallis and post hoc Dunn test used to compare groups using a significance level of 0.05. In the more viscous hydrogels, Artemia salina nauplii decreased drastically in 24 h, while the 15% and 20% hydrogels had no statistical differences from the negative control. The 10% and 20% hydrogels were statistically different from the negative control when comparing cell culture data. Our findings suggest that chitosan/L-arginine hydrogels could be used in humans without toxic effects. However, more trials and tests are needed to evaluate tooth movement rate during orthodontic treatment.

Characterisation of bioactive compounds from leaves of Smilax fluminensis Steud. by gc-MS and LC-DAD-MS, and analysis of its antioxidant and ecotoxicological activities

Smilax fluminensis Steud. is distributed in Central and South America, commonly named as ‘salsaparilha’ or ‘japicanga’. In the present work, the chemical composition was determined, antioxidant and cytotoxic effects were evaluated for the ethanol extract (EE) and fractions from leaves. Fatty acid esters and phytol were characterised in the hexane (HEX) fraction. O-glycosylated flavonols and flavones, caffeic acid derivatives, and steroidal saponins were annotated for EE, and dichloromethane (DCM), ethyl acetate (AC), and hydroethanol (HE) fractions. The samples contain flavonoids and phenolic compounds, and the AC fraction displayed the biggest concentration of these substances. Antioxidant potential was observed in all samples, being especially pronounced in the AC fraction by DPPH and FRAP assays, with IC50 values of 8.18 and 2.35 µg/mL, respectively. AC and HEX fractions showed 35% and 5% lethality at 1000 μg/mL, in the Artemia salina assay, and the other samples did not show a toxic effect.

Screening for Bioactive Metabolites in Leaves, Branches, and Roots of Mansoa hirsuta: Phytochemical, Toxicological and Antioxidant Aspects

In this study, secondary metabolites, toxicology and antioxidant properties of chloroform fractions from leaves (FCFMh), branches (FCGMh), and roots (FCRMh) of Mansoa hirsuta were investigated. The phytochemical screening detected flavonoids, especially chalcones. Through Liquid chromatography with mass spectrometry—LC–MS analysis, the flavonoids (isoorientin-2″-O-arabinoside), triterpenes (oleanolic acid and ursolic acid) and ceramide (phytosphingosine) were identified. From the Artemia salina assay, the fraction FCGMh was the most toxic (LC50 = 64.21 µg·mL−1), followed by FCRMh (LC50 = 87.61 µg·mL−1) and FCFMh (LC50 = 421.9 µg·mL−1). Concerning the cytotoxic potential, the root fraction (IC50 16.48 μg mL−1) displayed the highest cytotoxicity against the breast cancer cell line (4T1), followed by leaves (IC50 33.13 μg mL−1) and branches (IC50 of 47.13 μg mL−1). In conclusion, all the fractions of M. hirsuta showed cytotoxicity at the highest concentrations; however, remarkable biological properties were found for the root fractions. Computational analysis was performed using a molecular docking and pharmacophore approach to understand the antioxidant activity of its major metabolites.

Biological potentialities and chemical composition of Tarenaya aculeata roots and stems

Plant extracts are rich in secondary metabolites responsible for numerous biological activities. This study aimed to evaluate the antioxidant, antibacterial and photoprotective potentials, toxicity and chemical composition of extracts and fractions of stems and roots of Tarenaya aculeata. Phytochemical analyses were performed at qualitative and quantitative levels to evaluate the classes of secondary metabolites. The sun protection factor (SPF) and antioxidant potentials were determined spectrophotometrically, the antibacterial activity was tested against seven bacteria and the toxicity was evaluated using Artemia salina assay. Phytochemical screening revealed the presence of alkaloids, phenolic compounds, flavonoids, glycosides, tannins and saponins. The levels of phenolic compounds, tannins and alkaloids, SPF and antioxidant potentials showed greater results in the stem (SF) and root (RF) fractions in relation to the stem (SE) and root (RE) extracts. All samples exhibited a broad spectrum of antibacterial activity, with MIC values ​​ranging from 31.25 to 250 μg mL-1. SE, SF and RF caused mortality in A. salina larvae, with LC50 of 347.06, 34.71 and 85.39 μg mL-1, respectively, whereas RE was non-toxic. Thus, T. aculeata is rich in bioactive secondary metabolites, although further studies will be needed to characterize its chemical constituents and investigate their adverse effects.

Possible implementation of salicylate anions in lead detoxification

The water-soluble coordination polymer of formula {[Pb(Sal)2(H2O)]n} (SaLead), was obtained from the reaction between Pb(NO3)2 and the potassium salt of salicylic acid (SalH), an anti-inflammatory drug, which is also use as food preservation, in cosmetics etc. The compound was characterized by melting point, Attenuated Total Reflectance-Fourier Transform Infra-Red (ATR-FTIR) spectroscopy and X-ray diffraction crystallography (XRD) in solid state and in solution by Ultra Violet (UV) and 1H NMR spectroscopies. The binding affinity of SalK to Pb(II) ions towards SaLead was determined in order to examine its possible implementation in lead detoxification. The in vitro non-toxic behaviour of SalK and its complex SaLead was evaluated against normal human fetal lung fibroblast cells (MRC-5). The corresponding IC50 values are 260 ± 13 and > 1600 μM respectively. The non-genotoxic in vitro activity of SaLead was confirmed with the micronucleus (MN) assay, while its in vivo non-toxicity behaviour was evaluated with Allium cepa and Artemia salina assays.

Antibacterial activity of medicinal plants against Streptococcus agalactiae

Streptococcus agalactiae, group B Streptococcus (GBS), infects and causes severe diseases in humans and numerous animal species, including fish, given its ability to cross the host-specific barrier. The emergence of antibiotic resistant GBS strains makes it necessary to look for alternatives to treat and prevent infections that it produces. The aim of the present study was to determine the antibacterial activity of ethanolic and aqueous extracts of medicinal plants from Misiones province, northeast Argentina, against GBS from humans and fish. We used human Streptococcus agalactiae ATCC® BAA-611™ and tilapia Streptococcus agalactiae ATCC® 51487™ strains. Minimum Inhibitory Dose (MID) was determined by the disc diffusion method. Minimum Inhibitory Concentration (MIC), Minimum Bactericidal Concentration (MBC), MBC/MIC ratio, drug synergism with commercial antibiotics, and resistance assays were determined with extracts that showed antibacterial activity. Medium Lethal Dose 50 (LD50) was determined by the Artemia salina assay. For ethanolic and aqueous Eugenia uniflora L. extracts, we obtained a MID = 0.5 mg.disc-1. For both extracts of Eugenia uniflora L., the MIC and MBC values were 1 mg.mL-1 and 5 mg.mL-1, respectively. The MICI (MBC/MIC ratio) = 5 qualified the action of these extracts as bacteriostatic. The drug synergism assay with ampicillin, erythromycin, and clindamycin combination and extracts showed indifference. The LD50 of the aqueous extract was 0.82 mg.mL-1 indicating moderate toxicity. This work is a first step to identify chemical compounds in native medicinal plants of Misiones, Argentina, that could mean an alternative for the treatment of Streptococcus agalactiae infections.

Diplofuranoxin, a disubstituted dihydrofuranone, was produced together with sphaeropsidin A and epi-sphaeropsidone by Diplodia subglobosa, an emerging ash (Fraxinus excelsior L.) pathogen in Europe

An undescribed disubstituted dihydrofuranone, named diplofuranoxin, was isolated, together with the six well known metabolites sphaeropsidins A and C, epi-sphaeropsidone, mellein and cis- and trans-4-hydroxymelleins, from the fungal species Diplodia subglobosa, an emerging pathogen involved in the ash dieback aetiology in Europe. Currently, the disease represents the main threat to European ash heritage and the wood associated industry. Diplofuranoxin, was characterized essentially by NMR and HRESIMS spectra as (3Z)-3-(2,3-dihydroxybutylidene)-5-methyldihydrofuran-2(3H)-one. Its relative and absolute configuration was determined by joining NOESY NMR experiments and computational analysis of electronic circular dichroism spectrum. All the metabolites were screened for phytotoxic, antioomycetes and zootoxic activities and only sphaeropsidin A and epi-sphaeropsidone were active in two out of three bioassays performed. In addition, sphaeropsidin A completely inhibited mycelium growth of Phytophthora cambivora, whereas the inhibition rate of epi-sphaeropsidone was less than 50% at the higher concentration used. Both metabolites were inactive in the Artemia salina assay. Results obtained in this study have allowed to characterize for the first time the main metabolites produced in vitro by D. subglobosa and to increase the knowledge on the metabolic profile of Botryosphaeriaceae for a correct taxonomic classification of the strains belonging to this family.

Phytochemical Study and Antiglioblastoma Activity Assessment of Plectranthus hadiensis (Forssk.) Schweinf. ex Sprenger var. hadiensis Stems.

Glioblastoma (GB) is the most malignant form of primary astrocytoma, accounting for more than 60% of all brain tumors in adults. Nowadays, due to the development of multidrug resistance causing relapses to the current treatments and the development of severe side effects resulting in reduced survival rates, new therapeutic approaches are needed. The genus Plectranthus belongs to the Lamiaceae family and is known to be rich in abietane-type diterpenes, which possess antitumor activity. Specifically, P. hadiensis (Forssk.) Schweinf. ex Sprenger has been documented for the use against brain tumors. Therefore, the aim of this work was to perform the bioguided isolation of compounds from the acetonic extract of P. hadiensis stems and to investigate the in vitro antiglioblastoma activity of the extract and its isolated constituents. After extraction, six fractions were obtained from the acetonic extract of P. hadiensis stems. In a preliminary biological screening, the fractions V and III showed the highest antioxidant and antimicrobial activities. None of the fractions were toxic in the Artemia salina assay. We obtained different abietane-type diterpenes such as 7α-acetoxy-6β-hydroxyroyleanone (Roy) and 6β,7β-dihydroxyroyleanone (DiRoy), which was also in agreement with the HPLC-DAD profile of the extract. Furthermore, the antiproliferative activity was assessed in a glioma tumor cell line panel by the Alamar blue assay. After 48 h treatment, Roy exerted strong antiproliferative/cytotoxic effects against tumor cells with low IC50 values among the different cell lines. Finally, we synthesized a new fluorescence derivative in this study to evaluate the biodistribution of Roy. The uptake of BODIPY-7α-acetoxy-6β-hydroxyroyleanone by GB cells was associated with increased intracellular fluorescence, supporting the antiproliferative effects of Roy. In conclusion, Roy is a promising natural compound that may serve as a lead compound for further derivatization to develop future therapeutic strategies against GB.

Acaricide activity of extract and an isolated compound of Lithraea brasiliensis on Rhipicephalus microplus and selectivity actions against a non-target organism

Rhipicephalus microplus, known as the cattle tick, is a cause of great economic losses for dairy cattle farming because of its high frequency of occurrence and the difficulty in controlling it. This research characterized the chemical profile and evaluated the in vitro toxicity of crude Lithraea brasiliensis extract and its isolated compound against acaricide-resistant and acaricide-susceptible R. microplus strains. Acaricidal activity was evaluated using a larval immersion test and the selectivity against non-target organisms was assessed on Artemia salina assay. The chemical investigation by high-performance liquid chromatography coupled with mass spectrometry (i.e., HPLC-MS) analysis showed the presence of hydrolysable tannins as well as urushiol derivatives. Column chromatography (CC) was carried out on the extract to obtain fractions and an isolated compound. The extract exhibited significant activity against acaricide-resistant (LC50 0.64 mg/mL) and acaricide-susceptible (LC50 0.76 mg/mL) strains of R. microplus larvae. The isolated compound from the extract (urushiol II), exhibited LC50 of 1.11 mg/mL for acaricide-resistant larvae. For acute toxicity in A. salina, the extract showed LC50>100 μg/mL. Thus, our findings represent the first effort to demonstrate the potential of L. brasiliensis extract and urushiol II as potential natural acaricides to replace or to be integrated into the conventional control of R. microplus larvae.

Characterization of the essential oils from leaves of different sweet potato cultivars grown in Brazil

Sweet potato (Ipomoea batatas (L.) Lam.) leaves are commonly used as human foodstuff in some African and Asian countries. Scientific knowledge about the chemical composition and biological properties of these leaves is useful to allow humans to properly use this specific part of this plant. Thus, this study aimed to evaluate the chemical composition, antioxidant and toxicological potentials of the essential oils obtained from the leaves of four cultivars of sweet potatoes (Batata Roxa, IAPAR 69, Beni Imo and Batata-doce Japonesa) grown in Brazil. Essential oils were isolated by hydrodistillation (100°C, 4 hours) and their components were analyzed by GC/MS and GC/FID techniques. The antioxidant activities and the toxicological potentials of these essential oils were determined by ABTS and Artemia salina assays, respectively. Twenty-three compounds were found in these essential oils, with the sesquiterpene group being the major one. The compounds β-caryophyllene, β-copaene, γ-elemene, and β-elemene were found in concentrations of 1.08 – 28.63% of the essential oil among cultivars. β-Caryophyllene, α-caryophyllene, and δ-cadinene may explain the characteristic aroma of these essential oils. Their moderate antioxidant capacities demonstrated by the mean IC50(ABTS) value of (2.53 ± 0.27) mg mL−1 could be explained by the synergistic effects of α-cadinol, α-caryophyllene, γ-elemene, δ-cadinene, germacrene B, and phytol. The LD50(ASB) values (minimum: 0.60 ppm for cv. Beni Imo; maximum: 4.78 ppm for cv. Batata Roxa) are probably associated with δ-cadinene, α-cadinol, phytol, and α-caryophyllene. The high cytotoxicity attributed to this kind of essential oil shows that its use as a natural food preservative can be harmful to human health. The use of sweet potato leaves as a human foodstuff must be also considered with caution. As far as we are aware, no studies on the essential oils of these cultivars of sweet potato grown in Brazil were previously reported in the literature.

Pinofuranoxins A and B, Bioactive Trisubstituted Furanones Produced by the Invasive Pathogen Diplodia sapinea

Two new bioactive trisubstituted furanones, named pinofuranoxins A and B (1 and 2), were isolated from Diplodia sapinea, a worldwide conifer pathogen causing severe disease. Pinofuranoxins A and B were characterized essentially by NMR and HRESIMS spectra, and their relative and absolute configurations were assigned by NOESY experiments and computational analyses of electronic circular dichroism spectra. They induced necrotic lesions on Hedera helix L., Phaseolus vulgaris L., and Quercus ilex L. Compound 1 completely inhibited the growth of Athelia rolfsii and Phytophthora cambivora, while 2 showed antioomycetes activity against P. cambivora. In the Artemia salina assay both toxins showed activity inducing larval mortality.

Bioactive secondary metabolites produced by the emerging pathogen Diplodia olivarum

A new cleistanthane nor-diterpenoid, named olicleistanone (1), was isolated as a racemate from the culture filtrates of Diplodia olivarum, an emerging pathogen involved in the aetiology of branch canker and dieback of several plant species typical of the Mediterranean maquis in Sardinia, Italy. When the fungus was grown in vitro on Czapek medium, olicleistanone was isolated together with some already known phytotoxic diterpenoids identified as sphaeropsidins A, C, and G, and diplopimarane (2-5). Olicleistanone was characterized as 4-ethoxy-6a-methoxy-3,8,8-trimethyl-4,5,8,9,10,11-hexahydrodibenzo[de,g]chromen-7(6aH)-one. When D. olivarum was grown on mineral salt medium it produced (-)-mellein (6), sphaeropsidin A and small amounts of sphaeropsidin G and diplopimarane. Olicleistanone (1) exhibited strong activity against the insect Artemia salina L. (100% larval mortality) at 100 μg mL-1 but did not exhibit phytotoxic, antifungal or antioomycete activity. Among the metabolites isolated (1-6), sphaeropsidin A (2) was active in all bioassays performed exhibiting strong phytotoxicity on leaves of Phaseolus vulgaris L., Juglans regia L. and Quercus suber L. at 1 mg mL-1. Sphaeropsidin A (2) also completely inhibited mycelium growth of Athelia rolfsii, Diplodia corticola, Phytophthora cambivora and P. lacustris at 200 μg per plug, and was active in the Artemia salina assay. Also in this assay, diplopimarane (5) and sphaeropsidin G (4) were active (100% larval mortality). Diplopimarane also showed antifungal and antioomycete activities. Athelia rolfsii was the most sensitive species to diplopimarane. Sphaeropsidin C (3) and (-)-mellein (6) were inactive in all bioassays. These results expand knowledge on the metabolic profile of Botryosphaeriaceae, and embody the first characterization of the main secondary metabolites secreted by D. olivarum.

Organotin derivatives of cholic acid induce apoptosis into breast cancer cells and interfere with mitochondrion; Synthesis, characterization and biological evaluation

Organotin(IV) derivatives of cholic acid (CAH) with the formulae R3Sn(CA) (R = Ph- (1), n-Bu- (2)) and R2Sn(CA)2 (R = Ph- (3), n-Bu- (4) and Me- (5)) were synthesized. The compounds were characterized in solid state by melting point, FT-IR, 119Sn Mössbauer, X-ray fluorescence (XRF) spectroscopy and in solution by 1H NMR, UV–Vis spectral data and by Electrospray Ionisation Mass spectrometry (ESI-MS), High Resolution Mass spectrometry (HRMS), and atomic absorption analysis.The in vitro bioactivity of 1–5 against human breast adenocarcinoma cancer cells MCF-7 (positive to hormone receptors) and MDA-MB-231 (negative to hormone receptors) reveal that triorganotin derivatives 1–2 exhibit significantly stronger activity than the corresponding diorganotin ones. Compound 5 is inactive against both cell lines at the concentrations tested. Triorganotins 1–2 inhibit selectively MCF-7 than MDA-MB-231 cells, suggesting hormone mimetic behavior of them. Organotins 1–4 inhibit both cancerous cell lines, stronger than cisplatin which rise up to 55-fold against MCF-7 and 170-fold against MDA-MB-231. The in vitro toxicity of 1–4 was evaluated on normal human fetal lung fibroblast cells (MRC-5), while their genotoxicity in vitro by micronucleus assay (MN). Moreover, the in vivo toxicity of 1–4 was tested by Artemia salina assay and their in vivo genotoxicity with Allium cepa test. The mechanism of action of 1–4 against MCF-7 was clarified in vitro by the means of cell morphology studies, cell cycle arrest, Acridine Orange/Ethidium Bromide (AO/EB) Staining, mitochondrial membrane permeabilization test and by their binding affinity toward the calf thymus (CT) DNA.

In Vivo and In Vitro Toxicity Testing of Cyanobacterial Toxins: A Mini-Review.

Harmful cyanobacterial blooms are increasing and becoming a worldwide concern as many bloom-forming cyanobacterial species can produce toxic metabolites named cyanotoxins. These include microcystins, saxitoxins, anatoxins, nodularins, and cylindrospermopsins, which can adversely affect humans, animals, and the environment. Different methods to assess these classes of compounds in vitro and in vivo include biological, biochemical, molecular, and physicochemical techniques. Furthermore, toxic effects not attributable to known cyanotoxins can be observed when assessing bloom material. In order to determine exposures to cyanotoxins and to monitor compliance with drinking and bathing water guidelines, it is necessary to have reliable and effective methods for the analysis of these compounds. Many relatively simple low-cost methods can be employed to rapidly evaluate the potential hazard. The main objective of this mini-review is to describe the assessment of toxic cyanobacterial samples using in vitro and in vivo bioassays. Newly emerging cyanotoxins, the toxicity of analogs, or the interaction of cyanobacteria and cyanotoxins with other toxicants, among others, still requires bioassay assessment. This review focuses on some biological and biochemical assays (MTT assay, Immunohistochemistry, Micronucleus Assay, Artemia salina assay, Daphnia magna test, Radionuclide recovery, Neutral red cytotoxicity and Comet assay, Enzyme-Linked Immunosorbent Assay (ELISA), Annexin V-FITC assay and Protein Phosphatase Inhibition Assay (PPIA)) for the detection and measurement of cyanotoxins including microcystins, cylindrospermopsins, anatoxin-a, saxitoxins, and nodularins. Although most bioassay analyses often confirm the presence of cyanotoxins at low concentrations, such bioassays can be used to determine whether some strains or blooms of cyanobacteria may produce other, as yet unknown toxic metabolites. This review also aims to identify research needs and data gaps concerning the toxicity assessment of cyanobacteria.

Synthesis, biological evaluation and molecular docking of 3-substituted quinazoline-2,4(1H, 3H)-diones

The quinazoline-2,4-diones scaffold is found in bioactive compounds, commercial drugs and exhibit important biological activities. However, their antidiabetic activity is rarely explored. For this purpose, an easy one-pot three-components and straightforward synthesis of 3-substituted quinazoline-2,4-diones was designed, in both, the catalyst- and solvent-free conditions under microwave irradiation. Additionally, the synthesized compounds were screened for in vitro α-amylase and α-glucosidase inhibitory activity, as well as antioxidants and cytotoxicity. The quinazoline-2,4-diones were isolated, with yields in the range of 30-65%. The compounds 3d, 3e, 3g and 3h displayed moderate activity against α-amylase and/or α-glucosidase enzymes compared with the acarbose drug. The molecular docking study revealed that all active compounds displayed a different type of intermolecular interaction in the pocked site of these enzymes. Interestingly, in the Artemia salina assay, the compound 3d exhibited a higher cytotoxic effect than 5-fluorouracil. All these results support the pharmacological potential of quinazoline-2,4-diones since all evaluated compounds behave as moderate inhibitors of the enzymes α-amylase and/or α-glucosidase. An easy one-pot three-components and straightforward synthesis of 3-substituted quinazoline-2,4-diones was designed, in both, the catalyst- and solvent-free conditions under microwave irradiation. Moreover, the in vitro α-amylase and α-glucosidase inhibitory activity, as well as antioxidants and cytotoxicity are reported.

Toxicity and Antimicrobial Activities of Amaranthus caudatus L. (Amaranthaceae) Harvested From Formulated Soils at Different Growth Stages.

This study examined the toxicity and antimicrobial effects of ethanol and aqueous extracts from Amaranthus caudatus grown on soils formulated from parent particles of silt, sand and clay in a glasshouse. Four different soils namely; sandy clay loam, loam, clayey loam and silty clay loam from were formulated were used for cultivation with the unfractionated soil which was the control. Crude extracts obtained from the plant shoots harvested at different growth stages were tested on some certain gram-negative and gram-positive bacteria and some fungi via agar dilution assay. The toxicity of the water and ethanol extracts was also examined via Artemia salina assay and the level of lethality was measured against Clarkson’s lethality scale. All aqueous samples, as well as ethanol extracts of flowering and pre-flowering harvests of control soil tested, were non-toxic (LC50 > 1 mg/mL). At post flowering, the ethanolic extracts were highly toxic mostly in clayey loam, control, sandy-clayey loam soils (LC50 < 0.5 mg/mL). Also, antifungal effects of the plant revealed that extracts inhibited the growth of Candida albicans significantly with mild effect on Candida glabrata, Penicillium chrysogenum and Penicillium aurantiogriseum suggesting that the plant is a promising pharmacological candidate in the treatment of candidiasis. For an optimal yield of non-toxic supplement for household consumption which may also serve as pharmacological precursors, clayey loam soil is recommended for cultivation and harvesting may occur at pre-flowering or flowering stage using ethanol and water as solvents of extraction.

Intercalation of olanzapine into CaAl and NiAl Layered Double Hydroxides for dissolution rate improvement: Synthesis, characterization and in vitro toxicity

The aim of this work was to develop and characterize different Layered Double Hydroxides (LDHs) loaded with of Olanzapine (OLZ), CaAl:OLZ and NiAl:OLZ, by thermogravimetry (TG), differential scanning calorimetry (DSC), Fourier Transform Infrared spectroscopy (FT-IR) and X-ray diffraction (XRD), dissolution rate improvement, inhibition of AAPH-induced hemolysis and toxicity prospections with Artemia salina assay. No peaks of OLZ were found on diffractograms of both systems (5%) indicating amorphization of OLZ. This behavior was decreased with the increasing of drug. FT-IR spectra showed decreasing, displacements, suppressions and enlargements of bands in specific regions suggesting OLZ intercalation in both HDLs. No OLZ endothermic events was found in DSC curves indicating a decrease in the drug crystallinity, excepting for samples with 30% of OLZ. The dissolution profile evidenced that in 45 min CaAl:OLZ 5% and NiAl:OLZ 5% presented the maximum drug solubilization of 89.08 and 61.66%, respectively. In the inhibition of AAPH-induced hemolysis, both systems, showed significant inhibition (p ≤ 0.05) compared to the negative control, and Artemia salina assay evidenced that both HDLs (5%) did not cause the significant death of the specimens compared to OLZ in 24 h. The exposed results reinforced the proposed use of LDHs as functional excipients.

Bioguided isolation of N-malonyl-(+)-tryptophan from the fruit of Pithecellobium dulce (Roxb.) Benth. that showed high activity against Hymenolepis nana

Pithecellobium dulce is distributed in America and Asia where is widely used in traditional medicine. This study describes the bioguided fractionation of the methanol extract (ME) obtained from the P. dulce fruit that showed in vitro activity against Hymenolepis nana; Artemia salina assay was used to determine toxicity; and the purified compound was computationally analysed to obtain its absorption-distribution-metabolism-excretion-and-toxicity properties (ADMET). The ME and its fractions were more active than praziquantel (PZQ), and the purified compound was characterized as N-malonyl-(+)-tryptophan (NMT). Parasites treated with NMT showed shorter paralysis and death times (5 and 7 min) than those treated with PZQ (15 and 30 min), both used at 20 mg/mL. Toxicity and ADMET prediction results supported the slight-hazardousness and efficacy of the assayed fractions/compound. This is the first report of the antiparasitary activity of both the P. dulce ME and NMT, showing their potential to treat human H. nana infections.