Infectious Diseases Society of America.

National Institute of Standards and Technology における超伝導研究及び生活

In humans, microbial cells (including bacteria, archaea, and fungi) greatly outnumber host cells. Candida albicans is the most prevalent fungal species of the human microbiota; this species asymptomatically colonizes many areas of the body, particularly the gastrointestinal and genitourinary tracts of healthy individuals. Alterations in host immunity, stress, resident microbiota, and other factors can lead to C. albicans overgrowth, causing a wide range of infections, from superficial mucosal to hematogenously disseminated candidiasis. To date, most studies of C. albicans have been carried out in suspension cultures; however, the medical impact of C. albicans (like that of many other microorganisms) depends on its ability to thrive as a biofilm, a closely packed community of cells. Biofilms are notorious for forming on implanted medical devices, including catheters, pacemakers, dentures, and prosthetic joints, which provide a surface and sanctuary for biofilm growth. C. albicans biofilms are intrinsically resistant to conventional antifungal therapeutics, the host immune system, and other environmental perturbations, making biofilm-based infections a significant clinical challenge. Here, we review our current knowledge of biofilms formed by C. albicans and closely related fungal species.

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Candida albicans Biofilms and Human Disease.

Medically Important Fungi: A Guide to Identification

Antibacterial biohybrid nanofibers for wound dressings.

Cosmetics, like any product containing water and organic/inorganic compounds, require preservation against microbial contamination to guarantee consumer’s safety and to increase their shelf-life. The microbiological safety has as main goal of consumer protection against potentially pathogenic microorganisms, together with the product’s preservation resulting from biological and physicochemical deterioration. This is ensured by chemical, physical, or physicochemical strategies. The most common strategy is based on the application of antimicrobial agents, either by using synthetic or natural compounds, or even multifunctional ingredients. Current validation of a preservation system follow the application of good manufacturing practices (GMPs), the control of the raw material, and the verification of the preservative effect by suitable methodologies, including the challenge test. Among the preservatives described in the positive lists of regulations, there are parabens, isothiasolinone, organic acids, formaldehyde releasers, triclosan, and chlorhexidine. These chemical agents have different mechanisms of antimicrobial action, depending on their chemical structure and functional group’s reactivity. Preservatives act on several cell targets; however, they might present toxic effects to the consumer. Indeed, their use at high concentrations is more effective from the preservation viewpoint being, however, toxic for the consumer, whereas at low concentrations microbial resistance can develop.

https://www.mdpi.com/1420-3049/23/7/1571/pdf/1

Cosmetics Preservation: A Review on Present Strategies.

Introduction Naphthoquinone derivatives are under investigation as potential therapeutic agents. The antibacterial and antifungal activity of lawsone and of some novel naphthoquinone derivatives was assessed in vitro. Methods The antimicrobial activity was determined using diffusion disk and the broth microdilution methods against seven bacteria and three Candida species, according to recommendations of the Clinical and Laboratory Standards Institute. Results Two compounds (P05 et P06) presented a good antibacterial effectiveness against two gram-positive bacteria. No antifungal potency was observed against the three Candida albicans strains used in the test. Conclusion Our results prove that the introduction of substituents on ketone function position 4 decreased the antimicrobial properties of the synthetized compounds.

http://dspace.univ-tlemcen.dz/bitstream/112/5622/1/MEDMAL%20rahmoun.pdf

Antibacterial and antifungal activity of lawsone and novel naphthoquinone derivatives

Naphthoquinones are compounds widely distributed in the environment, both as natural products and as pharmaceutical agents. They have been the subject of much research due to their pharmacological activities. In this study, methanol extract of henna and a series of synthesized structural analogue of lawsone have been assessed for their antimicrobial activities. Methanol extract of henna and eight naphthoquinones derivatives were tested as potential antimicrobial agents against twelve bacteria and three Candida species using the agar disc diffusion and broth microdilution methods according to guidelines recommended by the Clinical and Laboratory Standards Institute. Besides 2b and 3b, methanol extract and all the synthesized compounds 1a, 2a, 1b and 1c, 2c and 3c showed weak-to-strong activity against at least one tested strain. However, the compounds 1c and 1b were found to have the most effective activity against pathogenic bacteria and displayed an activity 8 to 64 fold higher than that othe structural analogue, lawsone. Their MICs ranged from 8-64 µg ml-1. Henna extract was found to have an interesting activity. Our results indicate an effective in vitro activity of 1,4-naphthoquinone derivatives and suggest the benefits of further studies for its application in antibiotherapy.

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Antimicrobial Activities of the Henna Extract and Some Synthetic Naphthoquinones Derivatives

Context: Lawsonia inermis Linn. (Lythraceae) or henna has been used since the earliest times as a medicine, preservative, and cosmetic. It has long been recommended in traditional medicine as an astringent, purgative, and abortifacient.Objective: Lawsone and six extracts of L. inermis plant, used by Algerian traditional healers to treat infectious diseases, were screened for their antifungal activity against filamentous fungi.Materials and methods: Water and five organic extracts – DMSO, ethanol, chloroform, ethyl acetate, and di-ethyl ether – of L. inermis leaves, collected in the area of Adrar (Algeria), were prepared by soaking 25 g of powdered plant in 100 mL of solvent. The extracts were screened for antifungal activity using the poisoned food technique against five filamentous fungi.Results: Results demonstrated that the best yield (8.03%) was obtained with the ethanol extract. The commercial lawsone showed potentially interesting MICs against the strains Fusarium oxysporum (12 µg/mL) and Aspergillu...

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Antifungal activity of the Algerian Lawsonia inermis (henna)

Ammodaucus leucotrichus and Citrullus colocynthis from algerian Sahara: Ethnopharmacological application, phytochemical screening, polyphenols content and antioxidant activity of hydromethanolic extracts

K. Boucherit

Papers

Cosmetics Preservation: A Review on Present Strategies.

Antibacterial and antifungal activity of lawsone and novel naphthoquinone derivatives

Antimicrobial Activities of the Henna Extract and Some Synthetic Naphthoquinones Derivatives

Antifungal activity of the Algerian Lawsonia inermis (henna)

Ammodaucus leucotrichus and Citrullus colocynthis from algerian Sahara: Ethnopharmacological application, phytochemical screening, polyphenols content and antioxidant activity of hydromethanolic extracts