C apsicum fruits as functional ingredients with antimicrobial activity: an emphasis on mechanisms of action

Capsicum spp. fruits (CFs) are a basic ingredient in the diet and have been used as active ingredients in the pharmaceutical, cosmetic, and food products, due to their antioxidant, anti-inflammatory, antiseptic, and antimicrobial properties. The antimicrobial activity is the most studied property due to its effectiveness against pathogenic species, however, few studies have focused on the mechanisms of action involved. Therefore, this review discusses the effects generated by the CFs compounds on the viability and metabolism of microorganisms, highlighting the mechanisms by which these compounds exert their antimicrobial effects. The information provided shows that CFs are mainly source of capsaicinoids and phenolic compounds responsible for the inhibition of bacteria, yeasts, and fungi, through an increase in the permeabilization of the membrane and cell wall. Also, these compounds show an antiviral effect associated with the inactivation of virus binding proteins, preventing their replication and infection. Despite this, there is still a lack of information about the mechanisms that regulate the interactions between CFs compounds and food-important-microorganisms. Therefore, future research should focus on new antimicrobial compounds from CFs for their subsequent use against novel infectious agents, mainly virus of importance in health such as SARS-CoV-2.

A novel technique for the preparation of curd (Dahi) by PVDF membrane-based strip

Preparation of curd at home is quite challenging as it requires skills like addition of proper amount of starter culture, maintenance and storage of inoculum for the preparation of good and consistent quality curd. The present work utilized bacterial attachment property of PVDF (Polyvinylidene fluoride) membrane to prepare a strip which can be dipped into milk for the preparation of consistent quality curd. Shelf-life of the strip is around 100 days. The strip prepared curd was well comparable with the curd prepared by the commercial inoculum based on their pH, % lactic acid, % syneresis and bacterial load. Strip of size 5 × 5 cm2 was enough for preparation of 500 mL curd. It was proved by different analytical techniques like AFM, SEM and FTIR that PVDF was not having any leaching property during curd preparation. It can also be used in repeated contact with food products, as it is FDA (Food and Drug Administration) compliant and non-toxic. The curd strip has significant industrial relevance as it is a cost-effective alternative of any commercial inoculum (very expensive) and also meets the demand of consumers with the rising health awareness and busy lifestyles. Further, it is spillage proof, portable, ready-to-use.

Supplementary Information

The online version contains supplementary material available at 10.1007/s13197-021-05339-3.

Effectiveness of Chilli Powder Incorporation to Microbial Loads, Physicochemical and Sensory Characteristics of Vietnamese Fermented Pork Roll (Nem Chua)

Vietnamese fermented pork roll (Nem Chua) is delicious by its distinctive and unforgettable sweet, crunchy and spicy feeling. It becomes a specialty of many regions in Vietnam. Recently consumers always pay much attention to hygiene. Spices and herbs can be considered as alternatives of artificial additives. This research evaluated the possibility of chilli powder incorporated to Vietnamese fermented pork roll (Nem Chua) during storage. Different percentages of chilli powder (0÷2.5 %) were added Nem Chua. In 12 hour-interval, samples were taken to examine Enterobacteriaceae load, pH, thiobarbituric acid value (TBA), total volatile bases nitrogen (TVB-N), overall acceptance (sensory score). During 60 hours of lactic fermentation, Enterobacteriaceae load decreased with the amount of chilli powder added. On the control sample, Enterobacteriaceae load increased during storage. Much more reduction of pH value was noticed when increasing chilli powder. There was a significant retardation of TBA and TVB-N accumulation by chilli powder addition. At 1.5% of chilli powder supplemented, the highest sensory score was noticed. Chilli powder would be a promising natural spice to control food hygiene and maintain physciochemical and sensory attributes of meat products.

Mgll Knockout Mouse Resistance to Diet-Induced Dysmetabolism Is Associated with Altered Gut Microbiota

Monoglyceride lipase (MGLL) regulates metabolism by catabolizing monoacylglycerols (MAGs), including the endocannabinoid 2-arachidonoyl glycerol (2-AG) and some of its bioactive congeners, to the corresponding free fatty acids. Mgll knockout mice (Mgll-/-) exhibit elevated tissue levels of MAGs in association with resistance to the metabolic and cardiovascular perturbations induced by a high fat diet (HFD). The gut microbiome and its metabolic function are disrupted in obesity in a manner modulated by 2-arachidonoyl glycerol (2-AG's) main receptors, the cannabinoid CB1 receptors. We therefore hypothesized that Mgll-/- mice have an altered microbiome, that responds differently to diet-induced obesity from that of wild-type (WT) mice. We subjected mice to HFD and assessed changes in the microbiomes after 8 and 22 weeks. As expected, Mgll-/- mice showed decreased adiposity, improved insulin sensitivity, and altered circulating incretin/adipokine levels in response to HFD. Mgll-/- mice on a chow diet exhibited significantly higher levels of Hydrogenoanaerobacterium, Roseburia, and Ruminococcus than WT mice. The relative abundance of the Lactobacillaceae and Coriobacteriaceae and of the Lactobacillus, Enterorhabdus, Clostridium_XlVa, and Falsiporphyromonas genera was significantly altered by HFD in WT but not Mgll-/- mice. Differently abundant families were also associated with changes in circulating adipokine and incretin levels in HFD-fed mice. Some gut microbiota family alterations could be reproduced by supplementing 2-AG or MAGs in culturomics experiments carried out with WT mouse fecal samples. We suggest that the altered microbiome of Mgll-/- mice contributes to their obesity resistant phenotype, and results in part from increased levels of 2-AG and MAGs.

Capsaicin and Gut Microbiota in Health and Disease

Capsaicin is a widespread spice known for its analgesic qualities. Although a comprehensive body of evidence suggests pleiotropic benefits of capsaicin, including anti-inflammatory, antioxidant, anti-proliferative, metabolic, or cardioprotective effects, it is frequently avoided due to reported digestive side-effects. As the gut bacterial profile is strongly linked to diet and capsaicin displays modulatory effects on gut microbiota, a new hypothesis has recently emerged about its possible applicability against widespread pathologies, such as metabolic and inflammatory diseases. The present review explores the capsaicin–microbiota crosstalk and capsaicin effect on dysbiosis, and illustrates the intimate mechanisms that underlie its action in preventing the onset or development of pathologies like obesity, diabetes, or inflammatory bowel diseases. A possible antimicrobial property of capsaicin, mediated by the beneficial alteration of microbiota, is also discussed. However, as data are coming mostly from experimental models, caution is needed in translating these findings to humans.

Case Report of Presumed (In)voluntary Capsaicin Intoxication Mimicking an Acute Abdomen

Background

The clinical features of a presumed capsaicin intoxication have not been reported so far. Case Presentation. A 27-year-old man took part in a qualifying for a competition in spicy food tolerance. During this qualifying, he swallowed 4 chili peppers type Bhut jolokia (about 1 million Scoville units) and other extremely spicy foods; the total amount of capsaicin ingested (roughly calculated retrospectively) accounted for at least 600 mg. After 2½ hours, the patient developed severe abdominal pain, which led to hospital admission. In contrast to the severe symptoms, clinical, laboratory, and imaging examinations (ultrasound and plain X-ray of the abdomen) did not reveal any significant abnormalities. Treatment with analgesics resulted in complete regression of the abdominal pain within 30 hours.

Conclusions

The clinical picture in the view of pharmacological investigations on intestinal capsaicin infusions suggests that excessive doses of capsaicin can induce severe abdominal pain; the prolonged symptoms were probably due to the failure to vomit. Thus, a capsaicin intoxication must be considered in the differential diagnosis of an acute abdomen.

Transient receptor potential (TRP) channels: a metabolic TR(i)P to obesity prevention and therapy

Cellular transport of ions, especially by ion channels, regulates physiological function. The transient receptor potential (TRP) channels, with 30 identified so far, are cation channels with high calcium permeability. These ion channels are present in metabolically active tissues including adipose tissue, liver, gastrointestinal tract, brain (hypothalamus), pancreas and skeletal muscle, which suggests a potential role in metabolic disorders including obesity. TRP channels have potentially important roles in adipogenesis, obesity development and its prevention and therapy because of their physiological properties including calcium permeability, thermosensation and taste perception, involvement in cell metabolic signalling and hormone release. This wide range of actions means that organ-specific actions are unlikely, thus increasing the possibility of adverse effects. Delineation of responses to TRP channels has been limited by the poor selectivity of available agonists and antagonists. Food constituents that can modulate TRP channels are of interest in controlling metabolic status. TRP vanilloid 1 channels modulated by capsaicin have been the most studied, suggesting that this may be the first target for effective pharmacological modulation in obesity. This review shows that most of the TRP channels are potential targets to reduce metabolic disorders through a range of mechanisms.

Characteristics of Gouda Cheese Supplemented with Chili Pepper Extract Microcapsules

In this study, the physicochemical and sensory properties of Gouda cheese supplemented with microcapsules of chili pepper extract were evaluated. Microcapsules of pepper extract were prepared by coacervation technique using gum acacia-gelatin wall and chili pepper oil core. Changes in pH, lactic acid bacteria (LAB) population, and free amino acid (FAA) content after supplementation of Gouda cheese with chili pepper capsules were monitored during ripening. Texture and sensory characteristics of the Gouda cheese ripened for 6 months were evaluated. The supplementation of pepper extract microcapsules (0.5% or 1%, w/w) did not influence the pH values and LAB content of the Gouda cheese (p<0.05) during the ripening period. While the content of total FAA increased with the ripening process in all the cheese groups (p<0.05), no significant difference (p<0.05) in the content of total FAA was observed among the sample groups at each time point. The addition of pepper extract microcapsules (1%, w/w) to Gouda cheese significantly decreased hardness (p<0.05) and negatively affected sensory attributes in terms of taste and texture (p<0.05). The results demonstrated that supplementation with 0.5% pepper extract microcapsules could provide additional bioactive ingredients, along with maintenance of the quality of Gouda cheese.

Complete Genome Sequence of Lactobacillus acidophilus MN-BM-F01

Lactobacillus acidophilus MN-BM-F01 was originally isolated from a traditional fermented dairy product in China. The characteristics of this bacterium are its low post-acidification ability and high acid-producing rate. Here, we report the main genome features of L. acidophilus MN-BM-F01.

Effects of Japanese pepper and red pepper on the microbial community during nukadoko fermentation

Nukadoko is a fermented rice bran bed traditionally used for pickling vegetables in Japan. To date, the production of both homemade and commercial nukadoko has depended on natural fermentation without using starter cultures. Spices, Japanese pepper, and red pepper, are added to nukadoko empirically, but the functions of spices in nukadoko have not been fully elucidated. To investigate the effects of Japanese pepper and red pepper on nukadoko fermentation, we compared the chemical and microbiological changes during 2 months of fermentation of a laboratory model nukadoko with or without spices. The successive pH values and colony counts in the first 10 days showed that the spices promoted lactic acid bacteria (LAB) growth and fermentation in the nukadoko niche. The successive bacterial communities during natural fermentation of nukadoko were carefully monitored by pyrotag 16S rRNA analysis, and the effect of spices on the development and maintenance of the nukadoko microbiota was investigated. It was shown that addition of Japanese peppers and red peppers shortened the pre-lactic acid fermentation phase, during which Staphylococcus saprophyticus grew dominantly, and promoted the development of a microbiota that LAB dominated. Notably, the growth of the dominant LAB, Pediococcus pentosaceus, was improved by adding either Japanese pepper or red pepper. The differences in the LAB species, which were associated with the differences in chemical composition of the nukadoko, were dependent on the type of pepper used. We conclude that the spices used can affect the bacterial community and modulate its metabolic profile in nukadoko.

Capsaicin-induced transcriptional changes in hypothalamus and alterations in gut microbial count in high fat diet fed mice

Obesity is a global health problem and recently it has been seen as a growing concern for developing countries. Several bioactive dietary molecules have been associated with amelioration of obesity and associated complications and capsaicin is one among them. The present work is an attempt to understand and provide evidence for the novel mechanisms of anti-obesity activity of capsaicin in high fat diet (HFD)-fed mice. Swiss albino mice divided in three groups (n=8-10) i.e. control, HFD fed and capsaicin (2mg/kg, po)+HFD fed were administered respective treatment for 3months. After measuring phenotypic and serum related biochemical changes, effect of capsaicin on HFD-induced transcriptional changes in hypothalamus, white adipose tissue (WAT) (visceral and subcutaneous), brown adipose tissue (BAT) and gut microbial alterations was studied and quantified. Our results suggest that, in addition to its well-known effects, oral administration of capsaicin (a) modulates hypothalamic satiety associated genotype, (b) alters gut microbial composition, (c) induces "browning" genotype (BAT associated genes) in subcutaneous WAT and (d) increases expression of thermogenesis and mitochondrial biogenesis genes in BAT. The present study provides evidence for novel and interesting mechanisms to explain the anti-obesity effect of capsaicin.