A high-sucrose diet causes microbiota composition shift and promotes the susceptibility of mice to Salmonella Typhimurium infection.

A westernized diet characterized by high fat and sugar is tightly associated with the development of metabolic diseases and inflammatory bowel disease. Although a high-fat diet has been extensively studied for its involvement in various diseases, fewer studies have examined the impact of a high-sugar diet on the development of certain diseases, particularly enteric infections. This study aimed to explore the effect of a high sucrose diet on Salmonella Typhimurium-induced infection. C57BL/6 mice received a normal diet (Control) or a high sucrose diet (HSD) for eight weeks and then were infected by Salmonella Typhimurium. The high-sugar diet profoundly altered the relative abundance of certain microbial taxa. Bacteroidetes and Verrucomicrobiota were more abundant in normal diet-fed mice than in HSD-fed mice. Moreover, short-chain fatty acids (SCFAs) and branched-chain fatty acids (BCFAs) were significantly higher in mice from the control group than the HSD group. More S. Typhimurium counts in feces and other tissues were observed in HSD-fed mice after infection. Tight junction proteins and antimicrobial peptides were significantly decreased in HSD-fed mice. Fecal microbiota transplantation (FMT) demonstrated that mice that received normal fecal microbiota had lower Salmonella Typhimurium burdens compared with mice that received HSD fecal microbiota, indicating that the altered microbial communities are associated with the severity of infection. Together, these findings suggest that the excessive intake of sucrose disturbs intestinal homeostasis and predisposes mice to Salmonella-induced infection.

Live and pasteurized Akkermansia muciniphila decrease susceptibility to Salmonella Typhimurium infection in mice.

INTRODUCTION: The gut microbiome is vital for providing resistance against colonized pathogenicbacteria. Recently, specific commensal species have become recognized as important mediators of host defense against microbial infection by a variety of mechanisms. OBJECTIVES: To examine the contribution of live and pasteurized A. muciniphila to defend against the intestinal pathogen Salmonella Typhimurium in a streptomycin-treated mouse model of infection. METHODS: C57B6J mice were pretreated with phosphate-buffered saline (PBS), live Akkermansia muciniphila (AKK), and pasteurized A. muciniphila (pAKK) for two weeks, then mice were infected by S. Typhimurium SL 1344. 16S rRNA-based gut microbiota analysis was performed before and after infection. Bacterial counts in feces and tissues, histopathological analysis, gut barrier-related gene expression, and antimicrobial peptides were examined. Co-housing was performed to examine the role of microbiota in the change of susceptibility of mice to infection. RESULTS: AKK and pAKK markedly decreased Salmonella fecal and systemic burdens and reduced inflammation during infection. Notably, further characterization of AKK and pAKK protective mechanisms revealed different candidate protective pathways. AKK promoted gutbarrier gene expression and the secretion of antimicrobial peptides, and co-housing studies suggested that AKK-associated microbial community played a role in attenuating infection. Moreover, pAKK had a positive effect on NLRP3 in infected mice. We verified that pretreatment of pAKK could promote the expression of NLRP3, and enhance the antimicrobial activity of macrophage, likely through increasing the production of reactive oxygen (ROS), nitric oxide (NO), and inflammatory cytokines. CONCLUSION: Our study demonstrates that live or pasteurized A. muciniphila can be effective preventive measures for alleviating S. Typhimurium-induced disease, highlighting the potential of developing Akkermansia-based probiotics or postbiotics for the prevention of Salmonellosis.

Cherry juice alleviates high-fat diet-induced obesity in C57BL/6J mice by resolving gut microbiota dysbiosis and regulating microRNA.

Cherry is a nutrient-rich food that is good for health. This study demonstrated the inhibitory action of dietary cherry juice on high-fat diet (HFD)-induced obesity in mice. Cherry juice intervention significantly decreased body weight, fat contents, and blood lipid levels in obese mice. The overproduction of proinflammatory cytokines was suppressed by dietary cherry juice, which was accompanied by the elevation of tight junction proteins to maintain intestinal barrier. Moreover, dietary cherry juice restored the decreased production of short-chain fatty acids (SCFAs) by regulating the composition and abundance of gut microbiota. In addition, dietary cherry juice also suppressed the expression of some microRNAs associated with obesity such as miR-200c-3p, miR-125a-5p, miR-132-3p, and miR-223-3p and target proteins related with microRNAs in the inguinal or epididymal white tissue in the obese mice. These results offer a fresh perspective on cherry juice's role in the prevention of obesity caused by the HFD.

Polysaccharides from the seeds of Gleditsia sinensis Lam. attenuate DSS-induced colitis in mice via improving gut barrier homeostasis and alleviating gut microbiota dybiosis.

The seeds from Gleditsia sinensis Lam., a common ecologically and economically useful tree, have high economic and nutritional value. The protective effect of polysaccharides from Gleditsia sinensis Lam. seeds (ZJMP) against dextran sulfate sodium-induced colitis in mice was investigated in this study. ZJMP alleviated weight loss, reduced the disease activity index, prevented colon shortening, alleviated colonic tissue damage, and restored goblet cell secretion in colitic mice. Dietary ZJMP reduced proinflammatory cytokine overproduction in the colonic mucosa and serum, which was accompanied by suppression of NO levels and MPO and SOD activities. The addition of ZJMP increased the expression of Muc2 and tight junction proteins. Furthermore, dietary ZJMP partially reversed the alteration of gut microbiota in colitic mice by boosting the abundance of beneficial bacteria like Akkermansia, Lactobacillus, and Christensenella while lowering the abundance of harmful bacteria like Bacteroides, Prevotella, and Mucispirillum. Additionally, the decreased production of short-chain fatty acids in the colitic mice was recovered by ZJMP administration. The findings demonstrated the anti-inflammatory properties and mechanism of dietary ZJMP in the colon, which is essential for the sensible application of ZJMP in the prevention and amelioration of inflammation-related diseases as a nutritional supplement.

Live and pasteurized Akkermansia muciniphila attenuate hyperuricemia in mice through modulating uric acid metabolism, inflammation, and gut microbiota.

Akkermansia muciniphila (A. muciniphila) has been demonstrated to exhibit beneficial effects against various metabolic diseases, but whether A. muciniphila has an anti-hyperuricemia effect remains unexplored. In this study, live and pasteurized A. muciniphila were examined for their efficacy in alleviating hyperuricemia in mice. Live and pasteurized A. muciniphila (approximately 2 × 108 CFU) were given to a hyperuricemic mice model via oral gavage for three weeks. Both forms of A. muciniphila decreased serum urate and inhibited xanthine oxidase in the liver. In addition, fecal and urinal urate was increased in both treatment groups, which corresponds to the changes in the mRNA and protein expression levels of renal uric acid-related transporters (URAT1, GLUT9, and ABCG2) and intestinal ABCG2. Both forms of bacteria reduced the mRNA expression of inflammatory factors in the liver, kidneys and colon. Live A. muciniphila enhanced the expression of tight junction proteins and improved the dysbiosis of intestinal flora. These findings suggest that both live or pasteurized A. muciniphila could effectively attenuate hyperuricemia by moderating uric acid metabolism and inflammation, and live bacteria exhibit additional beneficial effects on the gut microbiota. These findings highlight that A. muciniphila could be potentially developed as a probiotic or postbiotic to combat hyperuricemia.

Propionate and Butyrate Inhibit Biofilm Formation of Salmonella Typhimurium Grown in Laboratory Media and Food Models.

Salmonella is among the most frequently isolated foodborne pathogens, and biofilm formed by Salmonella poses a potential threat to food safety. Short-chain fatty acids (SCFAs), especially propionate and butyrate, have been demonstrated to exhibit a beneficial effect on promoting intestinal health and regulating the host immune system, but their anti-biofilm property has not been well studied. This study aims to investigate the effects of propionate or butyrate on the biofilm formation and certain virulence traits of Salmonella. We investigated the effect of propionate or butyrate on the biofilm formation of Salmonella enterica serovar Typhimurium (S. Typhimurium) SL1344 grown in LB broth or food models (milk or chicken juice) by crystal violet staining methods. Biofilm formation was significantly reduced in LB broth and food models and the reduction was visualized using a scanning electron microscope (SEM). Biofilm metabolic activity was attenuated in the presence of propionate or butyrate. Meanwhile, both SCFAs decreased AI-2 quorum sensing based on reporter strain assay. Butyrate, not propionate, could effectively reduce bacterial motility. Bacterial adhesion to and invasion of Caco-2 cells were also significantly inhibited in the presence of both SCFAs. Finally, two SCFAs downregulated virulence genes related to biofilm formation and invasion through real-time polymerase chain reaction (RT-PCR). These findings demonstrate the potential application of SCFAs in the mitigation of Salmonella biofilm in food systems, but future research mimicking food environments encountered during the food chain is necessitated.

Association Between Child Abuse Experience and Pathological Internet Use Among Chinese University Students: The Mediating Roles of Security and Maladaptive Cognitions.

Research has revealed that child abuse experience can increase pathological Internet use; however, few studies have focused on the influence of child abuse experience on pathological Internet use. This study examined the mediating roles of security and maladaptive cognitions in the association between child abuse and pathological Internet use. A total of 918 Chinese university students participated in the study, with measurements of child abuse, security, maladaptive cognitions, and pathological Internet use being employed. Structural equation modeling results indicated that child abuse could positively predict (i) pathological Internet use, (ii) pathological Internet use through the mediating role of security, (iii) pathological Internet use through the mediating role of maladaptive cognitions, and (iv) pathological Internet use through the chain mediating role of security and maladaptive cognitions. These results indicated that security and maladaptive cognitions were the primary factors in the association between child abuse and pathological Internet use.

Impact of dietary components on enteric infectious disease.

Diets impact host health in multiple ways and an unbalanced diet could contribute to the initiation or progression of a variety of diseases. Although a wealth of information exists on the connections between diet and chronic metabolic diseases such as cardiovascular disease, diabetes mellitus, etc., how diet influences enteric infectious disease still remain underexplored. The review summarizes the current findings on the link between various dietary components and diverse enteric infectious diseases. Dietary ingredients discussed include macronutrients (carbohydrates, lipids, proteins), micronutrients (vitamins, minerals), and other dietary ingredients (phytonutrients and probiotic supplements). We first describe the importance of enteric infectious diseases and the direct and indirect relationship between diet and enteric infectious diseases. Then we discuss the effects of different dietary components on the susceptibility to or progression of enteric infectious disease. Finally, we delineate current knowledge gap and highlighted future research directions. The literature review revealed that different dietary components affect host resistance to enteric infections through a variety of mechanisms. Dietary components may directly inhibit or bind to enteric pathogens, or indirectly influence enteric infections through modulating immune function and gut microbiota. Elucidating the unique repercussions of different diets on enteric infections in this review may help provide dietary guidelines or design dietary interventions to prevent or alleviate enteric infectious diseases.

Dietary Acrylamide Intake Alters Gut Microbiota in Mice and Increases Its Susceptibility to Salmonella Typhimurium Infection.

Acrylamide (AA) has been extensively examined for its potential toxicological effects on humans and animals, but its impacts on gut microbiota and effects on hosts' susceptibility to enteric infection remain elusive. The present study was designed to evaluate the effect of AA on gut microbiota of mice and susceptibility of mice to S. Typhimurium infection. After four weeks' intervention, mice fed with AA exhibited significantly decreased body weight. Meanwhile, 16S rRNA gene sequencing showed reduced relative abundance of Firmicutes and increased abundance of Bacteroidetes in AA-treated mice prior to infection. In addition, we observed high relative abundance of Burkholderiales and Erysipelotrichales, more specifically the genus Sutterella and Allobaculum, respectively, in AA-treated mice before infection. Subsequently, the mice were orally infected with S. Typhimurium. The histological changes, systemic dissemination of S. Typhimurium, and inflammatory responses were examined. Compared to mice fed with normal diet, mice fed AA exhibited higher level of bacterial counts in liver, spleen, and ileum, which was consistent with exacerbated tissue damage determined by histological analyses. In addition, higher expression of pro-inflammaroty cytokines, p-IκBα, and p-P65 and lower mRNA expressions of mucin2, occludin, zo-1, claudin-1, and E-cadherin were detected in AA-treated mice. These findings provide novel insights into the potential health impact of AA consumption and the detailed mechanism for its effect on S. Typhimurium infection merit further exploration.

Jellyfish skin polysaccharides enhance intestinal barrier function and modulate the gut microbiota in mice with DSS-induced colitis.

Jellyfish skin polysaccharides (JSP) were isolated from Rhopilema esculentum Kishinouye and contained 55.11% polysaccharides and 2.26% uronic acid. To examine the anti-inflammatory, antioxidant and immunomodulatory activities of JSP in vivo, C57BL/6 mice were induced to develop ulcerative colitis by dextran sulfate sodium (DSS) and the roles of dietary JSP supplementation in modulating colitis were explored. JSP supplementation reduced the symptoms of colitis in mice, increased colon length, protected goblet cells, and improved intestinal epithelial integrity and permeability. JSP modulated oxidative stress and inflammatory responses, which was demonstrated by reduced MPO activity, NO level, and levels of pro-inflammatory cytokines including TNF-α, IL-1ß and IL-6 in mice. JSP suppressed NF-κB signaling pathways as evidenced by lower levels of phosphorylated p65 and IKB. Moreover, JSP supplementation enhanced the expression of tight junction proteins and mucins, and modulated the composition of the gut microbiota and the production of short-chain fatty acids. Taken together, these results reveal the anti-inflammatory effect of dietary JSP in vivo, suggesting the potential of JSP as a nutritional supplement or adjunct strategy in preventing or ameliorating colitis.

The Association Between Generalized and Specific Problematic Internet Use and Its Gender Differences Across Different Educational Levels.

This study had two aims: to test the effect and the effect size of specific problematic Internet use (SPIU) [online shopping, online pornography, social network site (SNS) usage, and Internet gaming] on generalized problematic Internet use (GPIU) and to reveal the gender differences in GPIU and SPIU for students from the elementary school level to the university level. In total, 5,215 Chinese students (2,303 males, mean age = 16.20 years, range = 10-23 years) from four types of schools (elementary school, junior high school, senior high school, and university) provided self-report data on demographic variables (gender and educational levels), online shopping, online pornography, SNS usage, Internet gaming, and GPIU. After calculations had been controlled for demographic variables, the results indicated that (i) online shopping, online pornography, SNS usage, and Internet gaming positively predicted GPIU-and Internet gaming was the most critical predictor of GPIU-and that (ii) gender differences were revealed in Internet gaming and GPIU in all educational levels, except at senior high school where the gender differences in GPIU were not significant. Significant gender differences were found for online shopping and online pornography for all educational levels above elementary school. These results provided further understanding of the association between GPIU and SPIU and gender differences in PIU, which suggested that gender differences across different educational levels should be considered in interventions of PIU.

Associations Among the Big Five Personality Traits, Maladaptive Cognitions, and Internet Addiction Across Three Time Measurements in 3 Months During the COVID-19 Pandemic.

The present study examined the longitudinal association among the Big Five personality traits, maladaptive cognitions, and Internet addiction during the COVID-19 pandemic. A total of 481 Chinese university students (247 men; mean age = 20.31 years) were surveyed three times (interval of 1 month) by using the Chinese version of the Big Five Personality Traits Scale, Maladaptive Cognitions Scale, and Internet Addiction Scale. The results of a cross-lagged panel analysis highlighted that (i) extraversion, agreeableness, conscientiousness, and openness were negatively associated with maladaptive cognitions and Internet addiction, whereas neuroticism was found to be positively associated with maladaptive cognitions and Internet addiction across time; (ii) associations among the Big Five personality traits, maladaptive cognitions, and Internet addiction were dynamic and bidirectional; and (iii) maladaptive cognitions played mediating roles in extraversion, agreeableness, conscientiousness, openness, and Internet addiction across time. The Big Five personality traits, maladaptive cognitions, and Internet addiction predicted each other across time, and maladaptive cognitions were likely to be the key mediating factor in the associations between the Big Five personality traits and Internet addiction, which supported and expanded the Davis' cognitive-behavioral model.

Fish oil extracted from Coregonus peled improves obese phenotype and changes gut microbiota in a high-fat diet-induced mouse model of recurrent obesity.

Recurrent obesity is rapidly emerging as a public health problem. Previous studies have confirmed that fish oil supplementation can alleviate obesity in mice; however, the effect of fish oil on recurrent obesity remains unclear. In the present study, the modulatory effects of fish oil extracted from Coregonus peled on the phenotypes and gut microbiota of recurrent obese mice were evaluated by MRI, OGTT, and bioinformatics analysis. We found that fish oil supplementation could significantly reduce the body weight gain, net weight gain, body fat distribution, and glucose tolerance. In addition, the composition and structure of gut microbiota were significantly shifted toward those of the control group by fish oil treatment. Moreover, the relative abundance of gut microbiota, such as Bacteroidetes, Bacteroidia, Lachnospiraceae, and Bifidobacterium, was markedly responding to the rapid dietary changes between fish oil and high-fat diet. Overall, our results confirmed that the alleviation of recurrent obesity using fish oil supplementation might be modulated by altering the hysteretic behavior and memory-like function of gut microbiota. We proposed that further studies are needed to elucidate the modulation mechanism.

Dehydrodiconiferyl alcohol from Silybum marianum (L.) Gaertn accelerates wound healing via inactivating NF-κB pathways in macrophages.

OBJECTIVES: The aim of this study was to investigate the molecular mechanisms of the efficacy of lignin compound dehydrodiconiferyl alcohol (DHCA) isolated from Silybum marianum (L.) Gaertn in improving wound healing. These findings preliminarily brought to light the promising therapeutic potential of DHCA in skin wound healing. METHODS: First, the effect of DHCA on healing in vivo was studied using a full-thickness scalp wound model of mice by topical administration. Histopathological examinations were then conducted by haematoxylin and eosin (H&E), Masson's trichrome staining and the immunofluorescence assay. Second, we further examined the anti-inflammatory mechanism of DHCA in lipopolysaccharide (LPS)-induced RAW 264.7 macrophages by immunofluorescence assay and Western blot analysis. KEY FINDINGS: DHCA could promote scalp wound healing in mice by enhancing epithelial cell proliferation and collagen formation and reducing inflammatory cells infiltration. Moreover, the NF-κB nuclear translocation was suppressed remarkably by DHCA administration in connective tissue of healing area. DHCA was also shown to inhibit production of nitric oxide (NO) and interleukin (IL)-1ß with downregulated inducible nitric oxide synthase (iNOS) expression in LPS-induced RAW 246.7 cells. More importantly, DHCA administration upregulated p-IκBα expression and induced nuclear translocation of NF-κB without affecting its expression. CONCLUSIONS: Our study indicated that DHCA exerted anti-inflammatory activity through inactivation of NF-κB pathways in macrophages and subsequently improved wound healing.

Zinc-Chelating Mechanism of Sea Cucumber (Stichopus japonicus)-Derived Synthetic Peptides.

In this study, three synthetic zinc-chelating peptides (ZCPs) derived from sea cucumber hydrolysates with limited or none of the common metal-chelating amino-acid residues were analyzed by flame atomic absorption spectroscopy, circular dichroism spectroscopy, size exclusion chromatography, zeta-potential, Fourier transform infrared spectroscopy, Raman spectroscopy and nuclear magnetic resonance spectroscopy. The amount of zinc bound to the ZCPs reached maximum values with ZCP:zinc at 1:1, and it was not further increased by additional zinc presence. The secondary structures of ZCPs were slightly altered, whereas no formation of multimers was observed. Furthermore, zinc increased the zeta-potential value by neutralizing the negatively charged residues. Only free carboxyl in C-terminus of ZCPs was identified as the primary binding site of zinc. These results provide the theoretical foundation to understand the mechanism of zinc chelation by peptides.

Identification and characterization of a polysaccharide from the roots of Morinda officinalis, as an inducer of bone formation by up-regulation of target gene expression.

Morinda officinalis is an important traditional tonic herbal medicine. In the present study, we found that crude polysaccharides extracted from M. officinalis, named MO90, could significantly increase the bone mineral density (BMD) of the whole femur, distal femur, and proximal femur in ovariectomized (OVX) rats. In addition, MO90 decreased the level of bone turnover markers and prevented the deterioration of trabecular microarchitecture. To investigate the fractions responsible for anti-osteoporosis activity, one novel inulin-type fructan, MOW90-1, was isolated from MOP90. Structural analysis indicated that MOW90-1 consists of a backbone of (2→1)-linked-ß-D-Fruf, and is terminated with (1→)-linked-α-D-Glcp and (2→)-linked-ß-D-Fruf. Furthermore, an in vitro anti-osteoporosis assay indicated that MOW90-1 promoted proliferation, differentiation, and mineralization of MC3T3-E1 cells by up-regulating the expression of runt-related transcription factor 2, osterix, osteopontin, and osteocalcin. In conclusion, our studies provide supporting evidence for future use of this novel M. officinalis fructan as a key nutrient of health products.

Biotransformation of 4-methylcoumarins by cambial meristematic cells of Camptotheca acuminata.

Cambial meristematic cell (CMC) suspension cultures were investigated as a new biotransformation system for the first time. Four 4-methylcoumarins substrates were transformed by CMCs of Camptotheca acuminata into four corresponding products, including 4,8-dimethylcoumarin-7-O-ß-d-glucopyranoside (I-1), 4,7-dimethylcoumarin-6-O-ß-d-glucopyranoside (II-1), 6-hydroxy-7-methoxyl-4- methylcoumarin (III-1), and 4,7-dimethylcoumarin-5-O-ß-d-glucopyranoside (IV-1), of which I-1, II-1, and IV-1 were new compounds. In addition, the biotransformation time and the amount of substrate were investigated to compare the biotransformation rate and optimize the biotransformation conditions of the four substrates in C. acuminata CMCs suspension cultures. The results suggested C. acuminata CMCs were able to select glycosylate phenolic hydroxyl groups of 4-methylcoumarins I, II, and IV, with high regio- and stereoselectivity, but no corresponding glycoside of any phenolic hydroxyl group of compound III was detected. Simultaneously, the result also showed that the C. acuminata CMCs were able to transform the 7-hydroxy groups of substrate III to its corresponding methylated products. Furthermore, the monoamine oxidase (MAO) inhibition activities of biotransformed products were evaluated, and the data showed that all the products possessed good MAO inhibition activities in vitro. In conclusion, C. acuminata CMCs could be applied to glycosylation biotransformation as a novel plant-based system due to the successful application of bioconversion of exogenous coumarins.

Identification of flavonolignans from Silybum marianum seeds as allosteric protein tyrosine phosphatase 1B inhibitors.

Protein tyrosine phosphatase 1B (PTP1B) is an attractive molecular target for anti-diabetes, anti-obesity, and anti-cancer drug development. From the seeds of Silybum marianum, nine flavonolignans, namely, silybins A, B (1, 2), isosilybins A, B (3, 4), silychristins A, B (5, 6), isosilychristin A (7), dehydrosilychristin A (8), and silydianin (11) were identified as a novel class of natural PTP1B inhibitors (IC50 1.3 7-23.87 µM). Analysis of structure-activity relationship suggested that the absolute configurations at C-7" and C-8" greatly affected the PTP1B inhibitory activity. Compounds 1-5 were demonstrated to be non-competitive inhibitors of PTP1B based on kinetic analyses. Molecular docking simulations resulted that 1-5 docked into the allosteric site, including α3, α6, and α7 helix of PTP1B. At a concentration inhibiting PTP1B completely, compounds 1-5 moderately inhibited VHR and SHP-2, and weakly inhibited TCPTP and SHP-1. These results suggested the potentiality of these PTP1B inhibitors as lead compounds for further drug developments.

Isolation, purification, characterization and bioactivities of a glucan from the root of Pueraria lobata.

The root of Pueraria lobata is considered to be a medicinal and edible herb for the treatment of diabetes, and it has a long history of application in China. To explore the constituents responsible for the anti-hyperglycemic activities of P. lobata, a water-soluble polysaccharide (PL70-1-1) was isolated and purified by using a DEAE-Cellulose 52 anion exchange column and a Sephacryl S-100 gel filtration column. Its molecular weight (2584 Da) was determined by high performance gel permeation chromatography (HPGPC). Its structure was deduced by Fourier transform-infrared spectroscopy (FT-IR), monosaccharide composition analysis, gas chromatography coupled with mass spectrometry (GC-MS) and nuclear magnetic resonance spectroscopy (NMR). It was deduced that PL70-1-1 was a glucan, and its main chain consisted of (1→)-linked ß-d-glucose, (1→4)-linked α-d-glucose, (1→4, 6)-linked ß-d-glucose, and (1→3)-linked α-d-glucose, and the branch chain consisted of (1→)-linked ß-d-glucose. The results of scanning electron microscopy showed that PL70-1-1 had a needle-like shape, and the surface had a scaly texture. The Congo red experiment showed that PL70-1-1 did not have a triple-helix structure. In addition, PL70 and PL70-1 displayed selective inhibitory effects on α-amylase and α-glucosidase in vitro. PL70 had remarkable α-glucosidase inhibitory activity. However, PL70-1-1 exhibited outstanding α-amylase inhibitory activity, with an IC50 of 3.945 µM in vitro. This indicated that its activity was 417 times higher than the positive control acarbose. PL70-1-1 may be beneficial as an α-amylase inhibitor, reducing the postprandial blood glucose level and treating type 2 diabetes.

Cytotoxic quinazoline alkaloids from the seeds of Peganum harmala.

Seventeen quinazoline alkaloids and derivatives, containing two pairs of new epimers, named as (S)- and (R)-1-(2-aminobenzyl)-3-hydroxypyrrolidin-2-one ß-d-glucopyranosyl-(1 → 6)-ß-d-glucopyranoside (1, 2), (S)- and (R)-vasicinone ß-d-glucopyranosyl-(1 → 6)-ß-d-glucopyranoside (3, 4), and a new enantiomer (12b), together with six known ones (5-8, 10, and 12a), and three pairs of known enantiomers (9, 11, and 13), were isolated from the ethanol extracts of the seeds of Peganum harmala L.. Their structures including the absolute configuration were elucidated by using 1D and 2D NMR, and ECD calculation approaches. The cytotoxic activities of all isolated compounds were evaluated. 11 showed moderate cytotoxicity against PC-3 cells with an IC50 value of 15.41 µM.