Nematicidal, larvicidal and antimicrobial activities of some new mannich base imidazole derivatives

Purpose: To synthesize Mannich base imidazole derivatives, and evaluate their antimicrobial, nematicidal and larvicidal properties .Methods: Compounds 1a-g and 2a-g were prepared using a Mannich condensation method. The chemical structures of compounds 2a-g were confirmed by Fourier transform infrared spectroscopy (IR), proton nuclear magnetic resonance (1H-NMR), carbon nuclear magnetic resonance (13C-NMR), and mass spectrometry (MS) and elemental analyses. Compounds 1a-f and 2a-f were screened for antimicrobial properties using an agar diffusion method. The nematicidal activity of the compounds was evaluated against juvenile Meloidogyne javanica as test organism while larvicidal activity was assessed against the urban mosquito, Culex. Quinquefasciatus, using a standard bioassay protocol.Results: Compounds 1b, 1g, 2e and 2g were highly active against a few bacterial organisms compared with the reference antibacterial, ciprofloxacin while the antifungal activity of compound 2d was high compared with the reference, clotrimazole. Compounds 1c, 1e, 1g, and 2e showed high toxicity levels of larvicidal activity based their half maximal lethal dose (LD50) values. Compounds 1d, 1e, 1f, 1g, 2d and 2e were highly toxic to nematodes.Conclusion: Compounds 1b, 1g, 2e and 2g may be useful as lead molecules for the development of new classes of larvicidal, nematicidal and antimicrobial agents

Synthesis and antimicrobial activity of some new pyrrole derivatives

New pyrrole derivatives were synthesized and structures were confirmed by IR, 1H NMR, 13C NMR, mass spectra, and elemental analyses data. The reaction was performed by using ordinary condensation type, which enabled to easy work-up and good yield. Synthesized compounds were screened for antimicrobial activity.KEY WORDS: Pyrrole, 1,3,4-oxadiazol-2-amine, 4H-1,2,4-triazol-3-ol, Cyclization, Antimicrobial activity, Structure activity relationship Bull. Chem. Soc. Ethiop. 2012, 26(3), 429-435.DOI: http://dx.doi.org/10.4314/bcse.v26i3.1

Larvicidal, nematicidal, antifeedant and antifungal, antioxidant activities of Mentha spicata (Lamiaceae) root extracts

Purpose: To evaluate the larvicidal, nematicidal, antifeedant, and antifungal effects of 10 solvent extracts of Mentha spicata root.Methods: Ten solvent extracts were investigated for their total flavonoid and phenolic content and screened for larvicidal, nematicidal, antifeedant, and antifungal activities. The total phenolic content of the extracts was determined using the Folin–Ciocalteu method, while total flavonoid content was determined by aluminium chloride (AlCl3) colorimetric assay. Four solvents extracts were screened for antifungal activity against Aspergillus niger, Candida albicans, recultured Cryptococcus neoformans, and Microsporum audouinii using the agar diffusion method. The nematicidal activity of the compounds was evaluated against the juvenile Meloidogyne javanica organism, while larvicidal properties were evaluated against the urban mosquito Culex quinquefasciatus using a standard bioassay protocol. The antifeedant activity of marine acclimated Oreochromis mossambicus was used for evaluating ichthyotoxic potential.Results: The total flavonoid content in the extracts ranged from 18.5 to 83.4 mg/g, and the amount of free phenolic compounds ranged from 14.7 to 91.9 mg/g of extract powder. The water extract of these plants exhibited significant antioxidant activity and significant levels of phenolics and flavonoids. The water extract exhibited higher larvicidal (LD50 = 11.77 μg/mL), nematicidal (LD50 = 11.78 μg/mL), antifeedant (LD50 > 40 μg/mL), and antifungal activities (minimum inhibitory concentration: 16 μg/mL) against M. audouinii compared with the other extracts.Conclusion: These results show that the water extract of Mentha spicata may be used as a potential natural alternative source of nutritional and pharmaceutical ingredients.Keywords: Mentha spicata, Larvicidal, Nematicidal, Antifeedant and Antifungal activities, Nutritional supplement, Pharmaceutical ingredient

Micro-algal lethality potentials of marine organisms collected from the Indian littoral

Microalgal lethality bioassay was developed to detect the toxic profile of organic extract of marine organisms and their possible significance in the context of antifouling activities. Organic extracts of seaweeds, Ulva fasciata and Hypnea musciformis, sponges, Dendrilla nigra, Axinella donnai and Clathria gorgonoides and a holothurian Holothuria scabra were used for the detection of microalgal lethality potential. The microalgae such as Isochrysis galbana, Chlorella salina and Nanochloropsis sp. were used for the assay. The findings revealed that H. scabra contained toxic secondary metabolites, which might have the reason for its potent antifouling activity. Invariably all extracts inhibited the growth of microalgae at various concentrations except H. musciformis and A. donnani, which induce the growth of microalgae to certain extent. Based on the present findings, it could be inferred that the ‘microalgal lethality bioassay’ could be used as a primary screening assay system for the detection of biotoxic and antifouling agents from marine organisms

Antagonistic Potentials of Marine Sponge Associated Fungi Aspergillus clavatus MFD15

Abstract: The development of resistance to multiple drugs is a major problem in the treatment of these infectious diseases. Multidrug Resistant Staphylococcus aureus (MRSA) and Candida sp, the major infectious agents have been recently reported in quite a large number of studies. With more intensive studies for natural therapies, marine-derived products have been a promising source for the discovery of novel bioactive compounds. A total of 45 marine fungi were isolated from the two sponges F. cavernosa and D. nigra were screened for antimicrobial activity against pathogenic bacteria and fungi. The novel basal media formulated in the present study resulted in increased frequency of fungal isolates when compared to all other media used in the present study. The cell free supernatant of fungi exhibiting the broad spectrum of activity was subjected to chemical analysis using different chromatographic systems including TLC, Column and GC-MS. Of the 15 fungal strains, 20% (3 strains) showed potential antagonistic activity against a panel of clinical pathogens used in the present study. Based on the antimicrobial activity of the isolates, Aspergillus clavatus MFD15 was recorded as potent producer displaying 100% activity against the tested pathogenic organisms. The TLC of the crude ethyl acetate extract produced 3 spots with Rf values of 0.20, 0.79 and 0.95, respectively. The active TLC fraction was purified in column chromatography which yielded 50 fractions. The active column fractions were combined and analyzed with FT-IR, UV-Vis and GC-MS. The chemical analysis of the active compound envisaged the active compound to be a triazole, 1H-1,2,4 Triazole 3-carboxaldehyde 5-methyl. The triazolic compound was bacteriostic for S. aureus and bactericidal for E. coli. The triazole treated fabric showed 50% reduction in the growth of E. coli, S. aureus, and S. epidermidis. Thus the purified compound can find a place in the database for the development of fabrics with antimicrobial properties. This is the first report that envisaged the production of triazole antimicrobial compound from sponge associated marine fungi from the Indian coast

Bioactivity of the red algae Asparagopsis taxiformis collected from the Southwestern coast of India

Among the diverse variety of red algae, Asparagopsis taxiformis constitutes one of the abundant biomass in the Kollam coast (Southwest coast of India). Therefore, in the present study, A. taxiformis was collected, extracted and fractionated using column chromatography. The individual fractions were evaluated in vitro for their antifouling, anticyanobacterial, piscicidal and crustaceans toxicity assays. The fraction eluted with 2:8, petroleum ether and ethyl acetate exhibited strong and broad spectrum of bioactivity. In antifouling assay against Limnea truncatula, the active algal fraction produced 80% of foot repellency at 150 mg/L whereas in anticyanobacterial assay, the active fraction inhibited 100% growth of Trichodesmium sp. at 320 mg/L. The algal fraction showed higher piscicidal effect at the level of 60 mg/L. The crustacean toxicity of the active fraction was also evaluated to find compounds without toxicity in non target organisms, Penaeus monodon and Macrobrachium rosenbergii. It was found that column fraction showed less toxicity against the non target organisms. The chemical constituents of the active fraction were identified by means of chromatographic systems such as TLC, reverse phase HPLC and GC-MS. The overall activity profile envisages that the active column fraction of A. taxiformis might contain synergistic bioactive metabolites that could be utilized for the control of fouling organisms, algal bloom and herbivorous/predaceous fishes in aquaculture ponds

Biological activity of the red alga Laurencia brandenii

The marine red alga Laurencia brandenii collected from the southwest coast of India (Indian Ocean) was extracted and fractioned using column chromatography. The individual fractions were evaluated in vitro via antimicrobial activity against six species of Microbial Type Culture Collection and three species of clinical human pathogens, antipest activity on Sitophilus oryzae, maggoticidal activity against 2nd instar larvae of Sarcophaga sp. and termiticidal activity against Microtermes obesi. It was found that the fraction eluted using petroleum ether:chloroform (6:4) exhibited broader biological activities. The phyco-constituents of the active fraction were identified by gas chromatography- -mass spectrometry (GC-MS) analysis. The GC-MS profile of the active fraction revealed that the main constituent was octadecadienoic acid (49.75%) followed by n-hexadecanoic acid (14.24%), which might have a functional role in the biological activities. The overall activity profile envisages that these bioactive compounds from L. brandenii could be utilized as a renewable natural resource for the development of novel environmental-compatible formulations for the control of human pathogens, pests, termites and maggots

Cut Throat Injuries at a University Teaching Hospital in Northwestern Tanzania: A Review of 98 cases.

Cut throat injuries though rarely reported in literature pose a great therapeutic challenge because multiple vital structures are vulnerable to injuries in the small, confined unprotected area. A sudden increase in the number of cut throat patients in our centre in recent years prompted the authors to analyze this problem. This study was conducted in our local setting to describe the etiology, patterns and treatment outcome of these injuries. This was a combined retrospective and prospective study of cut throat injury patients who were managed at Bugando Medical Centre between February 2009 and January 2013. Statistical data analysis was done using SPSS software version 17.0. A total of 98 patients with cut throat injuries were studied. Males outnumbered females by a ratio of 2.4: 1. The median age of patients was 26 years (range 8 to 78 years). Majority of patients (79.6%) had no employment and most of them (65.3%) came from rural community. Homicide was the commonest (55.1%) cause, followed by suicidal attempts (34.7%) and accidental (10.2%) injuries. Interpersonal conflict (24.4%) was the most common motivating factor for homicidal injury whereas psychiatric illness (16.2%) and road traffic accidents (9.2%) were the most frequent motivating factors of suicidal attempt and accidental injuries respectively. The majority of injuries were in Zone II accounting for 65.3% of cases and most of them had laryngeal (57.1%) injury. Surgical debridement, laryngeal/hypopharynx repair and tracheostomy were the most common surgical procedures performed in 93.9%, 73.5% and 70.4% of patients respectively. Postoperative complication rate was 57.1%, the commonest being surgical site infections in 28.1% of patients and it was significantly associated with late presentation and anatomical zones (P < 0.001). The overall median duration of hospitalization was 12 days. Patients who had postoperative complications stayed longer in the hospital and this was statistically significant (p = 0.011). Mortality rate was 11.2% and was significantly associated with co-morbidities, delayed presentation and presence of complications (p < 0.001). The follow up of patients was poor. Cut throat injuries are a major cause of morbidity and mortality among young adult males in our setting. Addressing the root causes of violence such as poverty, unemployment, and substance abuse will reduce the incidence of these injuries in our environment

LAP2 Is Widely Overexpressed in Diverse Digestive Tract Cancers and Regulates Motility of Cancer Cells

BACKGROUND: Lamina-associated polypeptides 2 (LAP2) is a nuclear protein that connects the nuclear lamina with chromatin. Although its critical roles in genetic disorders and hematopoietic malignancies have been described, its expression and roles in digestive tract cancers have been poorly characterized. METHODS: To examine the expression of LAP2 in patient tissues, we performed immunohistochemistry and real-time PCR. To examine motility of cancer cells, we employed Boyden chamber, wound healing and Matrigel invasion assays. To reveal its roles in metastasis in vivo, we used a liver metastasis xenograft model. To investigate the underlying mechanism, a cDNA microarray was conducted. RESULTS: Immunohistochemistry in patient tissues showed widespread expression of LAP2 in diverse digestive tract cancers including stomach, pancreas, liver, and bile duct cancers. Real-time PCR confirmed that LAP2β is over-expressed in gastric cancer tissues. Knockdown of LAP2β did not affect proliferation of most digestive tract cancer cells except pancreatic cancer cells. However, knockdown of LAP2β decreased motility of all tested cancer cells. Moreover, overexpression of LAP2β increased motility of gastric and pancreatic cancer cells. In the liver metastasis xenograft model, LAP2β increased metastatic efficacy of gastric cancer cells and mortality in tested mice. cDNA microarrays showed the possibility that myristoylated alanine-rich C kinase substrate (MARCKS) and interleukin6 (IL6) may mediate LAP2β-regulated motility of cancer cells. CONCLUSIONS: From the above results, we conclude that LAP2 is widely overexpressed in diverse digestive tract cancers and LAP2β regulates motility of cancer cells and suggest that LAP2β may have utility for diagnostics and therapeutics in digestive tract cancers