Rapid confirmation of five non-typhoidal Salmonella (NTS) serotypes using a low-cost portable-DIY OpenPCR© thermocycler

Aims@#OpenPCR is a low cost yet accurate thermocycler which can be self-built. The aim of the study is to highlight a low-cost alternative method for rapid confirmation of five predominant non-typhoidal Salmonella (NTS) serotypes using a multiplex PCR on a portable-DIY OpenPCR© thermocycler. @*Methodology and results@# Eight multiplex polymerase chain reaction (mPCR) samples containing genomic DNA of S. Agona selectively placed on the wells of the conventional PCR and OpenPCR© thermocyclers showed uniform heating in both thermocyclers. The limit of detection was similar for both thermocyclers for all five serotypes. The limit of detection for S. Typhimurium, S. Agona and S. Weltevreden was 10 pg/µL whereas the limit of detection for S. Enteriditis and S. Heidelberg was 1 pg/µL and 100 pg/µL, respectively. This assay incorporated a panel of unique genes; STM4495, SEN1392, SeHa-C4893, SeAg-B1096 and SENTW-3241 which were previously identified to be specific for S. Typhimurium, S. Enteritidis, S. Heidelberg, S. Agona, and S. Weltevreden, respectively, as well as the pan-Salmonella gene invA as internal control (IC) and pan-bacteria gene 16S rRNA to serve as amplification control (AC). The analytical specificity of the mPCR assay was found to be 100% for all five NTS using OpenPCR© thermocyclers. @*Conclusion, significance and impact of study@#The feasibility and low cost of the OpenPCR© thermocycler makes this device an ideal alternative for mPCR assay for rapid confirmation of NTS serotypes.

MicroRNA deregulation and cancer and medicinal plants as microRNA regulator

MircroRNAs (miRNAs) are short non-coding RNAs with a length of approximately 20-22 nucleotides, which interact with their target mRNAs at 3'-untranslated region by partial pairing. The miRNA-mRNA interaction leads to induction of mRNA degradation and eventually translational inhibition. Thus, miRNAs play an important role in virtually all cellular processes, especially differentiation, proliferation, migration, and apoptosis. The deregulation of miRNAs may lead to serious diseases including cancer. There is mounting evidence demonstrating the participation of miRNA regulation during carcinogenesis. In this review, we discuss an updated miRNA biogenesis, mechanisms involved in their deregulation, and their role in cancer development. This review also summarizes updated information on potential medicinal plants which regulate miRNA expression as a promising molecular miRNA therapeutic approach for cancers.

Cytotoxicity and genotoxicity assessment of Euphorbia hirta in MCF-7 cell line model using comet assay

Objective:To evaluate the cytotoxicity and genotoxicity activity of Euphorbia hirta (E. hirta) in MCF-7 cell line model using comet assay. Methods: The cytotoxicity of E. hirta extract was investigated by employing brine shrimp lethality assay and the genotoxicity of E. hirta was assessed by using Comet assay. Results: Both toxicity tests exhibited significant toxicity result. In the comet assay, the E. hirta extract exhibited genotoxicity effects against MCF-7 DNA in a time-dependent manner by increasing mean percentage of DNA damage. The extract of E. hirta showed significant toxicity against brine shrimp with an LC50 value of 620.382 μg/mL (24 h). Comparison with positive control potassium dichromate signifies that cytotoxicity exhibited by the methanol extract might have moderate activity. Conclusion:The present work confirmed the cytotoxicity and genotoxicity of E. hirta. However, the observed toxicity of E. hirta extracts needs to be confirmed in additional studies.

Antioxidant and antibacterial activity of different parts of Leucas aspera

Objective: To evaluate antioxidant, antimicrobial and cytotoxic activity of different parts (root, flower, leaf and stem) of Leucas aspera (L. aspera) (Labiatae). Methods: Different parts of L. aspera were extracted with 80% (v/v) methanol. The methanol extracts were subjected to antioxidant, antimicrobial and brine shrimp lethality assay. Results: All the extracts showed moderate to potent antioxidant activity, among which the root extract demonstrated the strongest antioxidant activity with the IC50 value of 6.552 μg/mL. Methanol extract of root possessed antioxidant activity near the range of vitamin E and thus could be a potential rich source of natural antioxidant. In case of antimicrobial screening, crude extracts of root, flower, leaf and stem showed notable antibacterial activity against tested microorganisms. The root extract showed the highest mean zone of inhibition ranging from 9.0-11.0 mm against tested microorganisms, at a concentration of 100 mg/mL. In the brine shrimp lethality bioassay, it was evident that the methanol root extract did not show significant toxicity. The LC50 value for 12 h and 24 h observation was 2.890 mg/mL and 1.417 mg/mL, respectively. Conclusions: The present finding suggests that the methanol root extract of L. aspera could be developed as pharmaceutical products.

Pharmacological screening of methanolic extract of Ixora species

Objective:To investigate the antimicrobial activity of methanolic extracts of different parts of Ixora species. Methods:Antimicrobial activity was carried out using disc diffusion assay against fungi, gram-positive and gram-negative bacteria. Results:All methanolic extracts of different parts of Ixora species showed a broad-spectrum of antibacterial and antiyeast activities, which inhibited the growth of at least one bacterium or yeast. There was no remarkable difference between different Ixora species observed in this study. Conclusions:The significant antimicrobial activity shown by this Ixora species suggests its potential against infections caused by pathogens. The extract may be developed as an antimicrobial agent.

Isolation and identification of Salmonella from curry samples and its sensitivity to commercial antibiotics and aqueous extracts of Camelia sinensis (L.) and Trachyspermum ammi (L.)

Objective: To isolate Salmonella from curry samples and to evaluate the drug sensitivity of the food-borne Salmonella and its susceptibility to specific plant extracts. Methods: Salmonella was isolated from the curry samples by standard microbiological methods and was confirmed by biochemical tests. The antibiotic susceptibility test was conducted by disc diffusion method using commercially available antibiotics such as ampicillin, tetracycline, chloramphenicol, kanamycin, and penicillin. In addition, the susceptibility of the food-borne Salmonella was also evaluated against the aqueous extracts of Camelia sinensis (L.) Theaceae (tea leaves) and the Trachyspermum ammi (L.) Apiaceae ( ajwain or omum seeds). Results: Out of fifty curry samples, only seven samples were identified to have Salmonella contamination. The Salmonella isolates showed a significant drug resistance pattern except for kanamycin. The plant extracts showed a considerable antibacterial activity against the isolates, indicating the presence of antimicrobial principle which can be exploited after complete pharmacological investigations. Conclusions:The present study demonstrates the occurrence of Salmonella in the curry samples, and shows significant drug resistance against most of the commercially available antibiotics, except kanamycin. Antimicrobial effect of the plant extracts against the food-bone Salmonella suggests that dietary including medicinal herbs would be one strategy to manage food borne pathogens.

In vivo toxicity study of Lantana camara

Objective: To investigate the toxicity of methanol extract of various parts (Root, Stem, Leaf, Flower and Fruit) of Lantana camara(L. Camara) in Artemia salina. Methods: The methanol extracts of L. camara were tested for in vivo brine shrimp lethality assay. Results: All the tested extract exhibited very low toxicity on brine shrimp larva. The results showed that the root extract was the most toxic part of L. camara and may have potential as anticancer agent. Conclusions:Methanolic extract of L. camara is relatively safe on short-term exposure.

A transmission electron microscopy study of the diversity of Candida albicans cells induced by Euphorbia hirta L. leaf extract in vitro

Objective: To determine the major changes in the microstructure of Candida albicans (C. albicans) after treatment with Euphorbia hirta (E. hirta) L. leaf extract. Methods: Transmission electron microscopy was used to study the ultrastructural changes caused by E. hirta extract on C.albicans cells at various exposure time. Results: It was found that the main abnormalities were the alterations in morphology, lysis and complete collapse of the yeast cells after 36 h of exposure to the extract. Whereas the control cultures showed a typical morphology of Candida with a uniform central density, typically structured nucleus, and a cytoplasm with several elements of endomembrane system and enveloped by a regular, intact cell wall. Conclusions: The significant antifungal activity shown by this methanol extract of E. hirta L. suggests its potential against infections caused by C. albicans. The extract may be developed as an anticandidal agent.

Isolation and identification of salmonella from curry samples and its sensitivity to commercial antibiotics and aqueous extracts of Camelia sinensis (L.) and Trachyspermum ammi (L.)

<p><b>OBJECTIVE</b>To isolate Salmonella from curry samples and to evaluate the drug sensitivity of the food-borne Salmonella and its susceptibility to specific plant extracts.</p><p><b>METHODS</b>Salmonella was isolated from the curry samples by standard microbiological methods and was confirmed by biochemical tests. The antibiotic susceptibility test was conducted by disc diffusion method using commercially available antibiotics such as ampicillin, tetracycline, chloramphenicol, kanamycin, and penicillin. In addition, the susceptibility of the food-borne Salmonella was also evaluated against the aqueous extracts of Camelia sinensis (L.) Theaceae (tea leaves) and the Trachyspermum ammi (L.) Apiaceae ( ajwain or omum seeds).</p><p><b>RESULTS</b>Out of fifty curry samples, only seven samples were identified to have Salmonella contamination. The Salmonella isolates showed a significant drug resistance pattern except for kanamycin. The plant extracts showed a considerable antibacterial activity against the isolates, indicating the presence of antimicrobial principle which can be exploited after complete pharmacological investigations.</p><p><b>CONCLUSIONS</b>The present study demonstrates the occurrence of Salmonella in the curry samples, and shows significant drug resistance against most of the commercially available antibiotics, except kanamycin. Antimicrobial effect of the plant extracts against the food-bone Salmonella suggests that dietary including medicinal herbs would be one strategy to manage food borne pathogens.</p>

Chemical composition and biological activity of the Centipeda minima (Asteraceae)

The antimicrobial activity of the Centipeda minima L. (Asteraceae) extract was evaluated against seven microorganisms using the disc diffusion method. The extract showed a broad spectrum of antimicrobial activity against all the tested bacterial strains, especially Enterobacter aerogenes, Klebsiella pneumonia, Staphylococcus aureus and Yersinia enterocolitica. The chemical composition of the extract obtained from Centipeda minima was analysed by GC–MS. Twenty three compounds, constituting about 84.75 % of the total extract, were identified. The main constituents were palmitic acid (7.47%), (Z,Z)-9-,12-octadecatrienoic acid (6.52%), (Z,Z,Z)-9-,12-octadecatrienoic acid (7.01%), phytol (7.01%), naptho[2.3-b]furan-2-(3H)-on (6.21%), 1-(1,2,3,4,7,7a-hexahydro-1,4,4,5-tetramethyl-1,3a-ethano-3aH-inden-6-yl)etanon (7.95%), 1,3,5-tri-tertbutyl-benzene (4.52%), (3Z)-2-methyl-3-octen-2-ol (5.95%) and artemisia ketone (4.98%). The extract was also tested against brine shrimp for toxicity. There was no significant toxicity as it only recorded a LC50 value of 4.92 mg/ml. The study shows that the extract is a good antimicrobial agent with potential applications in public health against diseases.