Immunomodulatory effects and associated mechanisms of Momordica charantia and its phytochemicals.

Momordica charantia L. (M. charantia), which is a member of the Cucurbitaceae family and widely distributed in tropical and subtropical regions, has been consumed as a vegetable and also used as herbal medicine for thousands of years worldwide. M. charantia has received great attention in biological and biomedical research due to its remarkable antidiabetic/hypoglycaemic, anti-inflammatory, antioxidant, antiviral and antitumour activities both in vivo and in vitro. Numerous studies have revealed that the typical health-promoting activities of M. charantia are mainly attributed to its phytochemicals including saponins, proteins/peptides, phenolic compounds, alkaloids, triterpenoids and polysaccharides. In particular, it has been attested that there is a strong relationship between the antidiabetic activity and the saponins and proteins of M. charantia. In recent years, studies on the immunoenhancing and immunostimulating effects of M. charantia have attracted much attention and made significant progress. Therefore, this review focuses on the immunomodulatory effects and associated mechanisms of M. charantia and its bioactive phytochemicals. The clinical applications of M. charantia in immune-related diseases are also discussed, aiming to broaden the exploration of M. charantia as a functional food.

Systematic Identification of Pathogenic Streptomyces sp. AMCC400023 That Causes Common Scab and Genomic Analysis of Its Pathogenicity Island.

Potato scab, a serious soilborne disease caused by Streptomyces spp., occurs in potato-growing areas worldwide and results in severe economic losses. In this paper, the pathogenicity of Streptomyces strain AMCC400023, isolated from potato scabs in Hebei Province, China, was verified systematically by the radish seedling test, the potato tuber slice assay, the potted back experiment, and the detection of phytotoxin thaxtomin A. Morphological, physiological, and biochemical characteristics were determined, and the 16S ribosomal RNA analyses of Streptomyces sp. AMCC400023 were carried out. To obtain the accurate taxonomic status of the pathogen strain, the whole genome was sequenced, and the phylogenetic tree among 31 Streptomyces genomes was formed. The average nucleotide identity (ANI) and in silico DNA-DNA hybridization (isDDH) were analyzed, and at the same time, the toxicity-related genes between Streptomyces sp. AMCC400023 and Streptomyces scabiei were compared, all based on the whole-genome level. All of the data supported that, instead of a member of S. scabiei, test strain Streptomyces sp. AMCC400023 was a distinct phytopathogen of potato common scab, which had a relatively close relationship with S. scabiei while separating clearly from S. scabiei at least in the species level of taxonomic status. The complete pathogenicity island (PAI) composition of Streptomyces sp. AMCC400023 was identified, which contained a toxin region and a colonization region. It was conjectured that the PAI of Streptomyces sp. AMCC400023 might be directly or indirectly acquired from S. scabiei 87-22 by horizontal gene transfer, or at the very least, there was a very close homologous relationship between the two pathogens as indicated by a series of analyses, such as phylogenetic relationships among 31 Streptomyces species, ANI and isDDH analyses, PAI structure mapping, thaxtomin A synthetic gene cluster tree construction, and most important, the collinearity analysis at the genome level.