Earthworm Depuration: Analysis of Coprophagy and Light Impacts

Earthworms are used as biomarkers to determine the bioavailability of contaminants. As such, their uptake of contaminants has been studied extensively. Protocols have been established to ensure that laboratory-obtained data are valid and comparable. However, the method of removing the organism’s gut content (depuration) before assessing the contaminant in the tissue is not standardized. The aim of this research project is to investigate some parameters for earthworm depuration: light conditions and coprophagy prevention. Eisenia fetida were depurated for 48 hours in two separate studies according to guidelines ASTM-E1676 and OECD Test No. 317. In one study, 2 frequencies of egesta removal were employed during depuration to prevent coprophagy and compared to the control (egesta and worms removed after 48 hours). In another study, the subjects and material egested were assessed under conditions of continuous darkness and the control (continuous light). The depuration methods that included egesta removal every 12 and 24 hours resulted in 62% and 10% more egested material per mg of earthworm than the control (filter paper disc change after 48 hours), respectively. The earthworms depurated in continuous darkness egested 94% more material per mg of earthworm than the control. The results indicate that depuration would be more total under continuous darkness and employing a coprophagy prevention method. These findings could lead to more efficient depuration methods.

Synthesis, Spectroscopic Characterization and Antibactrial Activities of Co(II) Complex of Ofloxacin Drug Mixed with Ascorbic Acid as secondary ligand

Ofloxacin is a quinolone antibiotic that is considered an efficient antibacterial drug with a broad spectrum of activity against anaerobic and aerobic bacteria and has strong antibacterial activity in vitro against many bacteria species by inhibiting their DNA-gyrase. In this study, the synthesis, physicochemical and spectroscopic characterization of Cobalt (II) metal complex with ofloxacin as primary ligand and ascorbic acid as the secondary ligand have been carried out. The complex was prepared by reflux method for four hours in methanol. The complex, with the molecular formula [Co(Ofl)(Asc)], was characterized by its color, solubility, melting point, FTIR, UV/Visible, 1H NMR, and 13C NMR spectroscopy. The color and the melting point suggest that complexation occurred. The Fourier Transform Infrared data for both the primary ligand (Ofl) and the secondary ligand (Asc) acted as tridentate ligands. Ofl coordinated to the Co(II) metal ion via the two carbonyl oxygen atoms and the oxygen atom of the hydroxyl group, whereas Asc coordinated to the metal through the carbonyl and enolic C-2 and C-3 hydroxyl groups. The electronic data suggests octahedral geometry for the complex. The ligands and the novel Co (II) complex were tested for in vitro antibacterial activity against gram-negative and gram-positive bacterial species using the filter paper disc agar diffusion method. Significant antibacterial activities were observed for the complex compared to the ligands. This research will aid in the development of more potent drugs that are resistant to organisms.

Chemical and Antibacterial Activity Evaluation of Alpinia calcarata and Alpinia zerumbet Grown in Foothills Agroclimatic Conditions of Northern India

Background: The member of the genus Alpinia (family: Zingiberaceae) is used in traditional medicine for various formulations for the food, spices, medicines, and perfume. Objective: The present study was carried out to analyse the compositional variability in leaf and rhizome essential oils of Alpinia calcarata Roscoe and Alpinia zerumbet (Pers.) B.L. Burtt & R.M. Sm. and to evaluate their antimicrobial activity against eight pathogenic bacteria strains. Methods: The essential oils were extracted by hydrodistillation and analysed by GC and GC-MS and the antibacterial activity was evaluated by filter paper disc diffusion and micro dilution broth assay. Results: A total of 31 compounds identified, forming 89.26-94.32% composition of A. calcarata and A. zerumbet. The leaf and rhizome oil of A. calcarata and A. zerumbet were mainly characterized by 1,8-cineole (15.61-43.63%), β-pinene (5.02-23.52%), terpinen-4-ol (1.00-20.87%), camphor (1.94-11.60%), and (Z)-β-ocimene (0.16-11.86%). endo-Fenchyl acetate (13.12-24.39%) was identified as marker constituents of rhizome essential oil of both A. calcarata and A. zerumbet. The antibacterial assay showed that leaf oil of A. calcarata has good activity against S. mutans, whereas its rhizome oil possess good activity against K. pneumoniae, E. coli, S. aureus, and S. epidermidis. However, the rhizome oil of A. zerumbet showed activity against S. mutans, B. subtilisS. aureus-2940 and S. epidermidis. Conclusion: The essential oils of A. calcarata and A. zerumbet with aroma chemicals viz. 1,8-cineole, ocimenes, terpinen-4-ol, α-pinene, β-pinenes and fenchyl acetate and significant antibacterial activities could be used for perfumery and fragrance related formulation.

Potential Assessment of Rumex spp. as a Source of Bioactive Compounds and Biological Activity

Secondary metabolites from the shoots and roots of three Rumex species collected from three different habitats were investigated (Rumex dentatus collected from cultivated land, R. pictus collected from the coastal desert and R. vesicarius collected from the inland desert) and tested for antioxidant activity as well as for anti-microbial activity against some human pathogenic bacteria. The present study indicated that the quantitative analysis of shoot and root extracts of three Rumex spp. were found to be rich in tannins and phenolics composition. The aerial parts of the three plants exhibited the highest significant values compared to the root parts. The MeOH extracts of Rumex species showed adequate antioxidant activity, wherein the IC50 values of the MeOH from the cultivated sample was 41.61 and 31.31 mg mL-1, coastal samples were 34.99 and 23.99 mg mL-1, while the sample of inland showed IC50 value of 41.59 and 31.67 mg mL-1, for root and shoot, respectively. Furthermore, using a filter paper disc assay, the MeOH extracts of the three Rumex species showed a substantial anti-microbial inhibitory effect on the growth of 10 pathogenic bacteria. According to sensitivity, the tested organisms could be sequenced as following: E. coli < K. pneumoniae ˂ S. typhi < P. aeruginosa for Gram-negative bacteria and B. subtilis < S. pneumoniae ˂ L. monocytoyenes < S. epidermis < S. aureus < B. cereus for Gram-positive bacteria. In addition, the antibacterial performance of R. dentatus root and R. vesicarius shoot MeOH extract is 100% broad spectrum against Gram-negative bacteria. A shoot of R. dentatus and R. pictus MeOH extract against Gram-positive bacteria is 83.3% broad spectrum. A further study is recommended for more characterization of the major compounds and assesses their efficiency and biosafety.

Dissemination of Aerosol and Splatter in Clinical Environment during Cavity Preparation: An In Vitro Study

Dental health care workers around the world are in a constant state of fear and anxiety because they work in a constrained space of the dental practice. During routine dental procedures, they are exposed to aerosol and splatter. These airborne particles pose a great risk of transmitting contagious infections to health care workers and patients, especially in an era of social distancing due to COVID-19. The current study was conducted to evaluate contamination amount, duration, the distance of aerosol, and splatter produced after cavity preparation using a two-hole and four-hole handpiece. The study was performed on a dental manikin in a dental simulation laboratory at the College of Dentistry, King Faisal University Al Ahsa. The dental manikin was set to a reclined position to simulate the clinical operatory position of the patient for dental restorative procedures. Aerosol and splatter were collected on Grade 1 qualitative cotton cellulose filter paper. These were placed on adhesive tape extending from the headrest of the dental manikin in six different directions (2, 4, 6, 8, 10, and 12 o’clock) for up to 60 inches and on certain positions of the operator and assistant such as the chest, head, forearms, upper leg, and inside facemask. Class V cavity preparation was done by the principal investigator at a specific time of 3 min on tooth #11 using a two-hole high-speed handpiece, then on the next day, Class V cavity preparation was performed on tooth #21 by a four-hole handpiece. High volume suction was used throughout the cavity preparation. Immediately after cavity preparation, the first filter paper disc was replaced with new ones in all positions. The second set of filter papers was removed after 30 min. Transparent grids were used to count the contamination area on the filter paper disc. No statistically significant difference was found in the mean amount of aerosol and splatter produced by both handpieces, however, a statistically significant difference was found in an amount of aerosol and splatter produced at a 12, 24, and 36 inches distance immediately after cavity preparation and 30 min after cavity preparation, regardless of the type of handpiece used. It is advisable to refrain from removing the personal protective barriers immediately after the procedure within the vicinity of the dental practice. The use of other adjuncts such as high volume suction to reduce the spread of aerosol and splatter is also recommended.

Gustatory Dysfunction among a Sample of Depressed Egyptian Adults under Antidepressants Therapy: A Retrospective Cohort Study

It is quite clear that the ability to perceive taste sensations significantly affects food choice, which consequently affects health status in the long term. Gustatory dysfunction is a neglected symptom among the depressed patients and those under antidepressants therapy, although these patients are suspectable to oral problems, due to general self-negligence related to mental disease, fear of dental treatment, and side effects of varied medications utilized in psychiatry. This study is aimed at assessing gustatory thresholds (detection and recognition thresholds) among a sample of 30 depressed Egyptian adults under antidepressants therapy for at least 3 months or psychotherapy with age ranging from 20 to 50 years old, seeking the Psychiatric Clinic at the Faculty of Medicine, Cairo University, Egypt. These patients were distributed into three equal groups (tricyclic antidepressants (TCA), selective serotonin reuptake inhibitors (SSRIs), and psychotherapy) and were assessed for gustatory detection and recognition thresholds using the filter paper disc method through a scoring system. The participants were also divided into normal taste group in which both the detection and recognition scores were 1, while the scores from 2 till 5 were considered as hypogeusia group and the score of 6 was considered as dysgeusia group. The TCA group was statistically significant from the other 2 groups in sweet detection thresholds ( p = 0.043) and sweet recognition thresholds ( p = 0.007). Hypogeusia for sweet was statistically significant ( p = 0.041), where it was more common among TCA (70%) than both SSRIs and the psychotherapy group (20%). Gustatory dysfunction was found to be mostly associated with TCA followed by SSRIs particularly for sweet taste thresholds. More attention has to be given to taste changes among these patients as oral health affects general health by causing considerable pain and by changing what people eat, their speech, and their quality of life and wellbeing. Proper awareness and evaluation of this problem will improve the quality of life for the depressed patients and avoid unnecessary treatment. This trial is registered with ClinicalTrials.gov ID: NCT03599011.

Short-chain cyanoacrylates and long-chain cyanoacrylates (Dermabond) have different antimicrobial effects

ObjectiveTo compare the antimicrobial effect in vitro of a short-chain cyanoacrylate with a long-chain cyanoacrylate (Dermabond, Ethicon, Johnson and Johnson, USA) against bacterial strains.Methods and analysisThe following bacterial strains were analysed: Staphylococcus aureus, Escherichia coli, Klebsiella pneumonia and Pseudomonas aeruginosa. For each microorganism, standardised sterile discs (6 mm) containing 10 µL of ethyl-cyanoacrylate and 2-octyl cyanoacrylate were applied to the plate. All plates received a blank filter-paper disc with no adhesive (control). All plates were incubated for 24 hours, after which the bacterial inhibitory halos, if present, were measured in millimetres in its greater length.ResultsInhibitory halos were observed for both adhesives for S. aureus. Inhibition halos were observed only for ethyl-cyanoacrylate for K. pneumoniae and E. coli. No inhibition halo was observed for P. aeruginosa in any sample. The relationship between the total size of the inhibition halos and the diameter of the paper filter for S. aureus was statistically significant compared with 2-octyl cyanoacrylate.ConclusionData shown conclude that ethyl-cyanoacrylate showed in vitro bacteriostatic activity for S. aureus, E. coli and K. pneumoniae. 2-Octyl cyanoacrylate showed in vitro lower bacteriostatic activity only against S. aureus when compared with ethyl-cyanoacrylate. No in vitro bactericidal activity of ethyl-cyanoacrylate or 2-octyl cyanoacrylate was observed.

Antibacterial activity of Calotropis procera against some common human pathogens

Calotropis procera (Oshaar, family Asclepiadaceae) is a species of flowering plant used as a folk medicine for the treatment of various ailments. This study aimed to evaluate antibacterial and antioxidant activities of C. procera aerial parts collected from Eastern Desert of Egypt (Wadi Hagul). The different extracts of C. procera aerial parts showed a significant antimicrobial inhibitory effect (P < 0.05) on growth of nine pathogenic bacterial using filter paper disc assay. Qualitative and quantitative phytochemical screening was carried out on water and different extracts. The present study indicated that this plant has a good inhibitory activity against Klebsiella pneumonia (21.3 mm), Escherichia coli (22.5 mm), and Staphylococcus aureus (21.6 mm). Moreover, methanol extract of C. procera exhibited wide broad spectrum (100%) followed by petroleum ether and water extracts (60%, each). Activity index (AI) illustrated variable antibacterial activities, that support the folkloric usage of medicinal plants for treatment of infectious pathogenic microorganism. The crude extract of C. procera showed adequate antioxidant activity, wherein methanol, ethyl acetate and petroleum ether extracts have an IC50 value of 0.81, 0.88 and 1.09 mg mL-1, respectively. Therefore, phytochemicals from C. procera could be used as a raw material for producing cheaper pharmaceuticals, pesticides in addition to many more important commercialized products of public use.

Culture-dependent analysis of seed bacterial endophyte, Pseudomonas spp. EGN 1 against the stem rot disease (Sclerotium rolfsii Sacc.) in groundnut

Background Groundnut, Arachis hypogaea L., crop is an important oil seed crop in India and is prone to attack by numerous fungal and viral diseases, among the soil-borne diseases, stem rot caused by Sclerotium rolfsii Sacc. is economically important. Main body of abstract Incidence (86.6%) of the stem rot disease was recorded in Coimbatore district, Tamil Nadu, India, during the roving survey. For its management, an attempt was made to isolate bacterial endophyte from peanut seeds of different groundnut cultivars by culture-dependent analysis. Totally, 16 bacterial endophytes (endophytes groundnut (EGN) 1 to EGN 16 along with standards TNAU-Pf1 and EPC 5) were obtained and characterized through morphological, biochemical and molecular studies and also phytostimulation activities were performed. Among the isolates, EGN 1 and EGN 4 showed positive results for indole acetic acid (IAA), siderophore, phosphate solubilization and protease tests in vitro. The dual culture analysis showed inhibition rates of 60.1% (dual plate assay), 68.23% (filter paper disc assay) and 100% (triangle method of streaking and culture filtrate assay) for EGN 1 against S. rolfsii. Further, the crude metabolite assay showed 97.7% inhibition in EGN 1, followed by 87.7% in EGN 4. The roll towel study showed a high vigour index of 4286.7 in EGN 1; hence, this isolate was chosen. Further, thin-layer chromatography (TLC) analysis showed various bands at 0.72 Rf, whereas GC-MS analysis indicated the prominent peaks of hexadecanoic acid and cis-vaccenic acid that may responsible for antifungal activity. In a molecular approach, the genomic DNA of EGN 1 strain was used to amplify a 1200 bp PCR-fragment and sequenced. Short conclusion The overall outcome of this study showed that Pseudomonas spp. EGN 1 had a great potential as a bio-stimulant and biocontrol agent to manage effectively the stem rot in peanut.