Editorial: Secondary Metabolites and Peptides as Unique Natural Reservoirs of New Therapeutic Leads for Treatment of Cancer and Microbial Infections

Microbial resistance has progressed rapidly and is becoming the leading cause of death globally. The spread of antibiotic-resistant microorganisms has been a significant threat to the successful therapy against microbial infections. Scientists have become more concerned about the possibility of a return to the pre-antibiotic era. Thus, searching for alternatives to fight microorganisms has become a necessity. Some bacteria are naturally resistant to antibiotics, while others acquire resistance mainly by the misuse of antibiotics and the emergence of new resistant variants through mutation. Since ancient times, plants represent the leading source of drugs and alternative medicine for fighting against diseases. Plants are rich sources of valuable secondary metabolites, such as alkaloids, quinones, tannins, terpenoids, flavonoids, and polyphenols. Many studies focus on plant secondary metabolites as a potential source for antibiotic discovery. They have the required structural properties and can act by different mechanisms. This review analyses the antibiotic resistance strategies produced by multidrug-resistant bacteria and explores the phytochemicals from different classes with documented antimicrobial action against resistant bacteria, either alone or in combination with traditional antibiotics.

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Farnesol and Tyrosol: Secondary Metabolites with a Crucial quorum-sensing Role in Candida Biofilm Development

Genes ◽

10.3390/genes11040444 ◽

2020 ◽

Vol 11 (4) ◽

pp. 444 ◽

Cited By ~ 4

Author(s):

Célia F. Rodrigues ◽

Lucia Černáková

Keyword(s):

Quorum Sensing ◽

Secondary Metabolites ◽

Regulation Of Gene Expression ◽

Main Role ◽

Dependent Manner ◽

Concentration Dependent Manner ◽

Microbial Infections ◽

Bacteria And Fungi ◽

Spherical Cells ◽

Biofilm Development

When living in biological and interactive communities, microorganisms use quorum-sensing mechanisms for their communication. According to cell density, bacteria and fungi can produce signaling molecules (e.g., secondary metabolites), which participate, for example, in the regulation of gene expression and coordination of collective behavior in their natural niche. The existence of these secondary metabolites plays a main role in competence, colonization of host tissues and surfaces, morphogenesis, and biofilm development. Therefore, for the design of new antibacterials or antifungals and understanding on how these mechanisms occur, to inhibit the secretion of quorum-sensing (e.g., farnesol and tyrosol) molecules leading the progress of microbial infections seems to be an interesting option. In yeasts, farnesol has a main role in the morphological transition, inhibiting hyphae production in a concentration-dependent manner, while tyrosol has a contrary function, stimulating transition from spherical cells to germ tube form. It is beyond doubt that secretion of both molecules by fungi has not been fully described, but specific meaning for their existence has been found. This brief review summarizes the important function of these two compounds as signaling chemicals participating mainly in Candida morphogenesis and regulatory mechanisms.

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Euphorbia-Derived Natural Products with Potential for Use in Health Maintenance

Biomolecules ◽

10.3390/biom9080337 ◽

2019 ◽

Vol 9 (8) ◽

pp. 337 ◽

Cited By ~ 6

Author(s):

Salehi ◽

Iriti ◽

Vitalini ◽

Antolak ◽

Pawlikowska ◽

...

Keyword(s):

Natural Products ◽

Chemical Composition ◽

Secondary Metabolites ◽

Essential Oils ◽

Biological Activities ◽

Health Maintenance ◽

The Third ◽

The World ◽

Microbial Infections ◽

Pure Compounds

Euphorbia genus (Euphorbiaceae family), which is the third largest genus of angiosperm plants comprising ca. 2000 recognized species, is used all over the world in traditional medicine, especially in the traditional Chinese medicine. Members of this taxa are promptly recognizable by their specialized inflorescences and latex. In this review, an overview of Euphorbia-derived natural products such as essential oils, extracts, and pure compounds, active in a broad range of biological activities, and with potential usages in health maintenance, is described. The chemical composition of essential oils from Euphorbia species revealed the presence of more than 80 phytochemicals, mainly oxygenated sesquiterpenes and sesquiterpenes hydrocarbons, while Euphorbia extracts contain secondary metabolites such as sesquiterpenes, diterpenes, sterols, flavonoids, and other polyphenols. The extracts and secondary metabolites from Euphorbia plants may act as active principles of medicines for the treatment of many human ailments, mainly inflammation, cancer, and microbial infections. Besides, Euphorbia-derived products have great potential as a source of bioactive extracts and pure compounds, which can be used to promote longevity with more health.

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Marine Bacterial Secondary Metabolites: A Treasure House for Structurally Unique and Effective Antimicrobial Compounds

Marine Drugs ◽

10.3390/md19100530 ◽

2021 ◽

Vol 19 (10) ◽

pp. 530

Author(s):

Ramanathan Srinivasan ◽

Arunachalam Kannappan ◽

Chunlei Shi ◽

Xiangmin Lin

Keyword(s):

Secondary Metabolites ◽

Marine Environment ◽

Antimicrobial Agents ◽

Drug Resistant ◽

Antimicrobial Compounds ◽

Antimicrobial Drugs ◽

Scientific Investigations ◽

Microbial Infections ◽

Resistant Strains ◽

Untapped Resource

The prevalence of antimicrobial resistance reduces the effectiveness of antimicrobial drugs in preventing and treating infectious diseases caused by pathogenic organisms, such as bacteria, fungi, and viruses. Because of the burgeoning growth of microbes with antimicrobial-resistant traits, there is a dire need to identify and develop novel and effective antimicrobial agents to treat infections from antimicrobial-resistant strains. The marine environment is rich in ecological biodiversity and can be regarded as an untapped resource for prospecting novel bioactive compounds. Therefore, exploring the marine environment for antimicrobial agents plays a significant role in drug development and biomedical research. Several earlier scientific investigations have proven that bacterial diversity in the marine environment represents an emerging source of structurally unique and novel antimicrobial agents. There are several reports on marine bacterial secondary metabolites, and many are pharmacologically significant and have enormous promise for developing effective antimicrobial drugs to combat microbial infections in drug-resistant pathogens. In this review, we attempt to summarize published articles from the last twenty-five years (1996–2020) on antimicrobial secondary metabolites from marine bacteria evolved in marine environments, such as marine sediment, water, fauna, and flora.

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Chapter 11 Importance of plant secondary metabolites for protection against insects and microbial infections

Advances in Phytomedicine - Naturally Occurring Bioactive Compounds ◽

10.1016/s1572-557x(06)03011-x ◽

2006 ◽

pp. 251-268 ◽

Cited By ~ 24

Author(s):

Michael Wink

Keyword(s):

Secondary Metabolites ◽

Plant Secondary Metabolites ◽

Microbial Infections

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Phytochemical and Mineral Screening ofZanthoxylum Tetraspermum(W & A)

E-Journal of Chemistry ◽

10.1155/2012/356247 ◽

2012 ◽

Vol 9 (1) ◽

pp. 121-130

Author(s):

K. Narayanasamy ◽

B. Ragavan

Keyword(s):

Secondary Metabolites ◽

Thin Layer ◽

Plant Extract ◽

Stem Bark ◽

Aqueous Extracts ◽

Preliminary Screening ◽

Antifungal Activities ◽

Therapeutic Value ◽

The Family ◽

Microbial Infections

The present study reveals the phytochemical and mineral screening ofZanthoxylum tetraspermumW & A., a member of the family‘Rutaceae’, which is used for treating microbial infections, antifungal activities and tooth ache. The preliminary screening of phytochemicals, thin layer chromatographic (TLC) profile of secondary metabolites and minerals from the stem bark ofZanthoxylum tetraspermumhave shown the presence of various important secondary metabolites such as alkaloids, flavonoids, glycosides, Phenols, sterols, saponins, tannins in higher levels in hydroethnolic and aqueous extracts and some minerals in the plant extract. The generated data has provided the basis for its therapeutic value and can be used as a therapeutant.

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Lycopene alleviates sulfamethoxazole-induced hepatotoxicity in grass carp (Ctenopharyngodon idellus) via suppression of oxidative stress, inflammation and apoptosis

Food & Function ◽

10.1039/d0fo01638a ◽

2020 ◽

Vol 11 (10) ◽

pp. 8547-8559

Author(s):

Hongjing Zhao ◽

Yu Wang ◽

Mengyao Mu ◽

Menghao Guo ◽

Hongxian Yu ◽

...

Keyword(s):

Oxidative Stress ◽

Secondary Metabolites ◽

Human Health ◽

Grass Carp ◽

Aquatic Environment ◽

Ctenopharyngodon Idellus

Antibiotics are used worldwide to treat diseases in humans and other animals; most of them and their secondary metabolites are discharged into the aquatic environment, posing a serious threat to human health.

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