Isolation and molecular identification of carotenoid-producing bacteria

Abstract. The production of pigments from bacteria is significant due to the low cost, high yield and ease of extract compared with other sources. Carotenoids are one of the most important pigments with antioxidant properties which are the precursor of vitamin A synthesis and have antibody overproduction ability, anti-tumor activity and inhibitory effect on the cardiovascular disease. The present study aimed to isolate and identify carotenoid-producing bacteria by highperformance liquid chromatography (HPLC) analysis of their carotenoid pigments. Twenty soil samples were collected from different regions of Tehran. After serial dilution each sample was cultured on BHI agar medium and incubated at 37°C. The pigment-producing bacteria were selected for further identification and their pigments were extracted bymethanol. The screening was carried out at two levels: i) selection of the strains by visual color inspection, ii) analysis of the pigment extracts by UV-VIS spectroscopy and HPLC. The isolates were identified by phenotypic methods and their 16S rDNA gene was amplified by PCR method and sequenced. Staphylococcus epidermidis, Micrococcus aloeverae, Citricoccus alkalitolerans, Rhodococcus zopfii, Arthrobacter agilis, Dietzia natronolimnaea and Rhodococcus ruber were identified as carotenoid-producing strains. The highest rate of absorption was observed using UV-VIS analysis in Staphylococcus epidermidis and Dietzia natronolimnaea. The comparison of HPLC analysis with the standard β-carotene curve showed that the carotenoids were beta-carotene. Micro-organisms are a potential source in the production of pigments. In this study we introduced two genera of bacteria (Staphylococcus epidermidis and Dietzia natronolimnaea) with carotenoid-producing ability

Antibacterial Effects of Hydro-alcoholic Extract of Pennyroyal, Cinnamon and Rhubarb on Klebsiella pneumoniae and Staphylococcus aureus: An In-vitro Study

Background: Medicinal plants have been used for many different purposes in the past. These plants may produce antimicrobial metabolites that affect the natural growth of microorganisms. The aim of this research was to study the antibacterial properties of rhubarb, cinnamon and pennyroyal on Staphylococcus aureus and Klebsiella pneumoniae. Materials and Methods: In this study, the effect of hydro-alcoholic extract of pennyroyal, cinnamon and rhubarb on Staphylococcus aureus and Klebsiella pneumoniae was investigated after their collection and extraction process. The Minimum Inhibitory Concentration (MIC) and the Minimum Bactericidal Concentration (MBC) of this extract on bacteria were also measured. Results: The MIC of hydro alcoholic extract of pennyroyal was above 400 mg/ml for both Klebsiella pneumoniae and Staphylococcus aureus. Also the MBC has been reported 400 and 500 mg/dL, respectively. The MIC of cinnamon extract for Klebsiella pneumoniae and Staphylococcus aureus were reported 250 and higher and 500 and higher, respectively. Also, the MBC was reported 500 and 600 mg/ml, respectively. Klebsiella pneumoniae was resistant to rhubarb plant extract, and the MIC and the MBC for Staphylococcus aureus were reported 200 mg/ml and higher and 400 mg/ml and higher, respectively. Conclusion: The results of this study demonstrated that the hydro alcoholic extract of cinnamon, pennyroyal and rhubarb has anti bacterial effect against Klebsiella pneumoniae and Staphylococcus aureus. Keywords Author Keywords:Pennyroyal; cinnamon; rhubarb; Klebsiella pneumoni; Staphylococcus aureus KeyWords Plus:GE

The landscape of exosomal non-coding RNAs in breast cancer drug resistance, focusing on underlying molecular mechanisms

Breast cancer (BC) is the most common malignancy among women worldwide. Like many other cancers, BC therapy is challenging and sometimes frustrating. In spite of the various therapeutic modalities applied to treat the cancer, drug resistance, also known as, chemoresistance, is very common in almost all BCs. Undesirably, a breast tumor might be resistant to different curative approaches (e.g., chemo- and immunotherapy) at the same period of time. Exosomes, as double membrane-bound extracellular vesicles 1) secreted from different cell species, can considerably transfer cell products and components through the bloodstream. In this context, non-coding RNAs (ncRNAs), including miRNAs, long ncRNAs (lncRNAs), and circular RNAs (circRNAs), are a chief group of exosomal constituents with amazing abilities to regulate the underlying pathogenic mechanisms of BC, such as cell proliferation, angiogenesis, invasion, metastasis, migration, and particularly drug resistance. Thereby, exosomal ncRNAs can be considered potential mediators of BC progression and drug resistance. Moreover, as the corresponding exosomal ncRNAs circulate in the bloodstream and are found in different body fluids, they can serve as foremost prognostic/diagnostic biomarkers. The current study aims to comprehensively review the most recent findings on BC-related molecular mechanisms and signaling pathways affected by exosomal miRNAs, lncRNAs, and circRNAs, with a focus on drug resistance. Also, the potential of the same exosomal ncRNAs in the diagnosis and prognosis of BC will be discussed in detail

Prunus armeniaca effects on expression of genes related to apoptosis in human breast cancer cells

Abstract Background Apoptosis inhibition depends on the balance between expression of some regulatory genes including Bax and c-FLIP, despite breast cancer has long been associated with disturbances in apoptosis regulation. The objective of present study was to determine the expression levels of Bax and c-FLIP mRNAs in 1 μg sample of total RNA obtained from MCF7 and MDA-MB-231 human breast cancer cells treated with Prunus armeniaca extract. Methods Prunus armeniaca effect was measured by MTT assay with different drug concentrations (0.5, 1, 1.5, 2, 2.5, 3, 3.5, 4, 4.5 and 5 mg/mL) at different incubation times (24, 48 and 72 h). Expression of Bax and c-FLIP mRNA levels was determined by qRT-PCR technique. Results The results of this study indicated that Prunus armeniaca significantly inhibited proliferation of cells in concentration-dependent manner in all the time of incubation (P < 0.05). Our findings also showed that the expression level of Bax and c-FLIP genes were increased in untreat group compared with control group in both of cancer cells at all the time (P < 0.001). Prunus armeniaca reduced the expression level of Bax and c-FLIP genes cancer cells as a time-dependence manner with respect to the untreat group significantly (P < 0.001). Conclusion The expression level of Bax and c-FLIP genes were significantly decreased under treatment of Prunus armeniaca extract and it may be helpful in the prevention and cure of breast cancer in usage of herbal remedies

Unfolded protein response signaling in hepatic stem cell activation in liver fibrosis

Frequent exposure to various external and internal adverse forces (stresses) disrupts cell protein homeostasis through endoplasmic reticulum (ER) capacity saturation. This process leads to the unfolded protein response (UPR), which aims to re-establish/maintain optimal cellular equilibrium. This complex mechanism is involved in the pathogenesis of various disorders, such as metabolic syndrome, fibrotic diseases, neurodegeneration, and cancer, by altering cellular metabolic changes integral to activating the hepatic stellate cells (HSCs). The development of hepatic fibrosis is one of the consequences of UPR activation. Therefore, novel therapies that target the UPR pathway effectively and specifically are being studied. This article covers the involvement of the UPR signaling pathway in cellular damage in liver fibrosis. Investigating the pathogenic pathways related to the ER/UPR stress axis that contribute to liver fibrosis can help to guide future drug therapy approaches