Investigating lactic acid bacteria genus Lactococcus lactis properties: Antioxidant activity, antibiotic resistance, and antibacterial activity against multidrug-resistant bacteria Staphylococcus aureus.

Background: Lactic acid bacteria (LAB) are utilized as a starter culture in the manufacturing of fermented dairy items, as a preservative for various food products, and as a probiotic. In our country, some research has been carried out, even if LAB plays a principal role in food preservation and improves the texture and taste of fermented foods, that is why we tried to evaluate their probiotic effect. The objective of this research was to determine the antibacterial activity of Lactococcus lactis (L. lactis) against Staphylococcus aureus (S. aureus) ATCC 29213, investigate their antioxidant activity, and characterize their sensitivity against 18 antibiotics. Methods: A total of 23 LAB (L. lactis subsp. cremoris, L. lactis subsp. Lactis diacetylactis, L. lactis subsp. lactis) were isolated from cow's raw milk. The antibacterial activity was performed using two techniques, competition for nutrients and a technique utilizing components nature, using the disk diffusion method. The sensitivity of the studied LAB to different antibiotics was tested on Man rogosa sharp (MRS) agar using commercial antibiotic disks. All strains of LAB were examined for their antioxidant activity. The antioxidant activity of L. lactis was tested by 2,2-diphenyl-1 picrylhydrazyl (DPPH). Results: The results showed that the MRS medium was more adapted than Muller Hinton Agar (MHA) to investigate the antibacterial activity of L. lactis against S. aureus ATCC 29213. Also, L. lactis exhibited a notable degree of antibacterial activity against S. aureus ATCC 29213. L. Lactis subsp. Lactis displayed higher antibacterial activities, followed by L. lactis ssp. lactis biovar. diacetylactis, and lastly, L. lactis ssp. cremoris against S. aureus ATCC 29213. Lc 26 among all strains of L. lactis showed a high potential antibacterial activity reaching 40 ± 3 mm against S. aureus ATCC 29213. All strains of L. lactis showed a slightly moderate antioxidant activity (10.56 ± 1.28%-26.29 ± 0.05 %). The results of the antibiotic resistance test indicate that all strains of L. lactis were resistant to cefotaxime, sulfamethoxazole-trimethoprim, and streptomycin and were sensitive to Ampicillin, Amoxicillin, Penicillin G, Teicoplanin, Vancomycin, Gentamicin 500, Tetracycline, and Chloramphenicol. These test results indicate that this strain falls within the criteria of not posing any harmful effects on human health. The important antibacterial properties recorded for all L. Lactis strains were derived from the production of antibacterial active metabolites, such as protein, diacetyl, hydrogen peroxide, and lactic acid, together with the fight for nutrients. Conclusion: This study suggests that the strains of L. lactis could be added as an antibacterial agent against S. aureus ATCC 29213 and can provide an important nutritional property for their antioxidant potential.

A very rare case of bacteraemia in a 4-year-old girl with osteopetrosis with probable Leuconostoc lactis infection.

Leuconostoc lactis (LLac) is a Gram-positive coccus of the family Leuconostocaceae . It can be found in a variety of vegetables and dairy products. LLac is an opportunistic pathogen with intrinsic resistance to vancomycin and teicoplanin. In this case report, we discuss a rare case of LLac-associated bacteraemia in a patient with osteopetrosis. A 4-year-old girl was admitted to the paediatric emergency department with acute fever without other signs. Blood culture revealed an infection with LLac. Using the streptococcus antibiogram, the isolate was resistant to vancomycin, teicoplanin, rifampicin and sulfamethoxazole-trimethoprim but sensitive to ß-lactams, gentamicin, streptomycin, azithromycin, clarithromycin, lincomycin, clindamycin and erythromycin. The patient was treated with intravenous ceftriaxone and gentamicin, and subsequently with oral amoxicillin. After a favourable course, she was discharged from the hospital on the 10th day. The modes of transmission and physiopathology of LLac remain unknown. Factors associated with this infection include compromised immunity, previous antibiotic therapy especially with vancomycin, and application of a central venous catheter. In our patient, the risk factors for infection were pancytopenia and multiple transfusions used to treat bone marrow failure. The source of the bacteraemia could have been the cutaneous route, but it could also have been digestive due to the reservoir of the bacteria. LLac is known as an opportunistic bacterium. Further studies on its pathogenesis and other risk factors are needed to understand the true prevalence of this potentially fatal bacterium in compromised individuals, such as the case of our patient.

Value of hematological parameters for predicting patients with severe coronavirus disease 2019: a real-world cohort from Morocco.

OBJECTIVE: Coronavirus disease 2019 (COVID-19) is a viral disease caused by severe acute respiratory syndrome coronavirus 2. The clinical manifestations and the evolution of patients with COVID-19 are variable. In addition to respiratory involvement, COVID-19 leads to systemic involvement and can affect the hematopoietic system. This study aimed to evaluate the prognostic value of hematological and hemocytometric parameters in predicting the severity of patients with COVID-19. METHODS: We performed a retrospective study at Mohammed VI university Hospital from 1 March to 11 November 2020. We collected demographic characteristics and hematological findings of incident COVID-19 cases. RESULTS: A total of 245 patients were included in our study. We found that the rate of lymphopenia was significantly reduced in patients who were severely affected by COVID-19. Additionally, the rate of neutrophilia, the neutrophil side fluorescence light signal, monocyte fluorescent intensity, monocyte size, the neutrophil-to-lymphocyte ratio, the platelet-to-lymphocyte ratio, and the lymphocyte-to-monocyte ratio were significantly elevated in patients who were severely affected by COVID-19. CONCLUSIONS: These results are consistent with the literature regarding the predictive value of these markers. A prospective validation in a large population with a longer follow-up is required.

Antibacterial and Antioxidant Activity of Dysphania ambrosioides (L.) Mosyakin and Clemants Essential Oils: Experimental and Computational Approaches.

Dysphania ambrosioides (L.) Mosyakin and Clemants, also known as Mexican tea, and locally known as Mkhinza, is a polymorphic annual and perennial herb, and it is widely used in folk medicine to treat a broad range of illnesses in Morocco. The aim of this study was to determine the phytochemical content and the antioxidant and the antibacterial properties of essential oils isolated from D. ambrosioides aerial components, growing in Eastern Morocco (Figuig). Hydrodistillation was used to separate D. ambrosioides essential oils, and the abundance of each phytocompound was determined by using Gas Chromatography coupled with Mass Spectrometry (GC-MS). In vitro 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assay and inhibition of ß-carotene/linoleic acid bleaching assays were used to determine D. ambrosioides essential oils' antioxidant activity. The findings revealed relative antioxidative power and modest radical scavenging. The antibacterial activity of the essential oils was broad-spectrum, with Escherichia coli, Staphylococcus aureus, and Enterococcus faecalis as the most susceptible strains tested. To elucidate the physicochemical nature, drug-likeness, and the antioxidant and antibacterial action of the identified phytocomponents, computational techniques, such as ADMET analysis, and molecular docking were used.

Loaded n-Hydroxyapatite/SSG 3D Scaffolds as a Drug Delivery System of Nigella sativa Fractions for the Management of Local Antibacterial Infections.

As a result of their close similarities to the inorganic mineral components of human bone, hydroxyapatite nanoparticles (n-HAp) are widely used in biomedical applications and for the elaboration of biocompatible scaffold drug delivery systems for bone tissue engineering. In this context, a new efficient and economic procedure was used for the consolidation of n-HAp in the presence of various Nigella sativa (NS) fractions at a near-room temperature. The research conducted in the present study focuses on the physicochemical properties of loaded n-HAp 3D scaffolds by NS fractions and the in vitro antibacterial activity against Gram-negative (Escherichia coli ATCC 25922, Pseudomonas aeruginosa ATCC 27853, Klebsiella pneumoniae ATCC 27853), and Gram-positive (Staphylococcus aureus ATCC 29213, Enterococcus faecalis ATCC 700603) bacteria. In order to better understand the effect of the inserted fractions on the HAp molecular structure, the elaborated samples were subject to Fourier transform infrared (FTIR) and X-ray diffraction (XRD) spectroscopic analyses. In addition, the morphological investigation by scanning electron microscope (SEM) of the loaded n-HAp 3D scaffolds demonstrated the presence of a porous structure, which is generally required in stimulating bone regeneration. Furthermore, the fabricated 3D composites exhibited significant antibacterial activity against all tested bacteria. Indeed, MIC values ranging from 5 mg/mL to 20 mg/mL were found for the HAp-Ethanol fraction (HAp-Et) and HAp-Hexane fraction (HAp-Hex), while the HAp-Aqueous fraction (HAp-Aq) and HAp-Methanol fraction (HAp-Me) showed values between 20 mg/mL and 30 mg/mL on the different strains. These results suggest that the HAp-NS scaffolds were effective as a drug delivery system and have very promising applications in bone tissue engineering.

Visceral leishmaniasis associated with macrophage activation syndrome: Case report and literature review.

BACKGROUND: The combination of visceral leishmaniasis (VL) and macrophage activation syndrome (MAS) makes the diagnosis difficult due to their similar clinical presentation, with a poor prognosis especially since the treatment is still poorly codified.We report the case of a 17-month-old female patient from Berkane, presenting for a 3 months history of anarchic fever with anemic syndrome made up of pallor and hemorrhagic syndrome made up of epistaxis. Physical examination revealed a temperature of 39 ° C, lower limbsedema, paleness of skin and mucous membranes, gingival petechiae, bleached hair, and hepatosplenomegaly. CASE PRESENTATION: The complete blood count showed pancytopenia with deep aregenerative normochromic normocytic anemia at 3 g/dL, leukocytes were at 4860/mm 3 with neutropenia at 680/mm 3 and thrombocytopenia at 12.000/mm3, the blood smear was without abnormality. These anomalies were associated with a hypoalbunemia, hypertriglyceridemia, hyperferritinemia, lactate dehydrogenase (LDH) level was at 337 IU/L, low prothrombin time (PT) at 56 % and fibrinogen level at 1 g/L. The direct Coombs test was positive. Examination of the myelogram revealed the presence of leishmania bodies and figures of hemophagocytosis. A diagnosis of visceral leishmaniasis associated with MAS was made.The patient was put on liposomal amphotericin B and corticosteroid therapy with good clinical and biological evolution and good therapeutic tolerance. CONCLUSION: The association of VL and MAS remains rare and should be evoked even in non-endemic areas since late diagnosis worsens the prognosis and may even be responsible for the death of patients despite an aggressive treatment.

Molecular Composition and Antibacterial Effect of Five Essential Oils Extracted from Nigella sativa L. Seeds against Multidrug-Resistant Bacteria: A Comparative Study.

Nigella sativa L. (NS) and its volatile compounds are well known for their broad spectrum of effects. This study aimed to investigate the variability of the chemical composition and the in vitro antibacterial activity of five essential oils (Eos) originated from Morocco, Saudi Arabia, Syria, India, and France. These five samples were grown under different edaphic and climatic conditions. The agar diffusion method and microdilution method in 96-well plates were used to test the sensitivity of multidrug-resistant strains clinically isolated from patients (methicillin-resistant Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, and Acinetobacter baumannii), for the determination of the minimum inhibitory concentration and bactericidal concentration. Among all the investigated Eos, the monoterpenes were highly present in the chemical composition. Moroccan, Saudi Arabian, and Syrian seeds were characterized by the presence α-phellandrene (20.03-30.54%), ß-cymene (12.31-23.82 %), and 4-caranol (9.77-14.27%). The Indian seeds were rich with 4-caranol (18.81%), ß-cymene (14.22%), α-phellandrene (10.58%), and ß-chamigrene (9.54%), while France NS was rich with estragole (20.22%) and D-limonene (14.63%). The minimum inhibitory (MIC) and bactericidal concentration (MBC) obtained for the four Eos (with the exception of France because of the low yield) tested were ranging from 3 to 40 µl/ml. Gram-positive (+) bacteria were slightly sensitive to the Eos tested than the Gram-negative (-) bacteria. The results of this study showed that the Eos of NS seeds show interesting antibacterial activity which could be associated to the existence of different bioactive compounds. Indeed, these compounds can be used for preventive or curative purposes in the face of the noncontrolled emergence of resistance to antibiotics.

Nigella sativa L. Phytochemistry and Pharmacological Activities: A Review (2019-2021).

Medicinal and aromatic plants are mainly characterized by the presence of different bioactive compounds which exhibit various therapeutic activities. In order to investigate the different pharmacological properties of different Nigella sativa extracts, a multitude of research articles published in the period between 2019 and 2021 were obtained from different databases (Scopus, Science Direct, PubMed, and Web of Science), and then explored and analyzed. The analysis of the collected articles allows us to classify the phytochemicals and the pharmacological activities through their underlying molecular mechanisms, as well as to explore the pharmacological activities exhibited by several identified compounds in Nigella sativa which allow a better understanding, and better elucidation, of the bioactive compounds responsible for the pharmacological effects. Also shown are the existence of other bioactive compounds that are still unexplored and could be of great interest. This review could be taken as a guide for future studies in the field.