Effects of Fiber Purified Extract of Carob Fruit on Fat Digestion and Postprandial Lipemia in Healthy Rats

Lactobacillus plantarum HF02 alleviates lipid accumulation and intestinal microbiota dysbiosis in high-fat diet-induced obese mice

BACKGROUND

Obesity is closely associated with lipid accumulation and intestinal microbiota dysbiosis. It has been proved that probiotics supplement contributes to alleviate obesity. The objective of this study was to investigate the mechanism by which Lactobacillus plantarum HF02 (LP-HF02) alleviated lipid accumulation and intestinal microbiota dysbiosis in high-fat diet-induced obese mice.

RESULTS

Our results showed that LP-HF02 ameliorated body weight, dyslipidemia, liver lipid accumulation, and liver injury in obese mice. As expected, LP-HF02 inhibited pancreatic lipase activity in small intestinal contents and increased fecal triglyceride levels, thereby reducing dietary fat hydrolysis and absorption. Moreover, LP-HF02 ameliorated the intestinal microbiota composition, as evidenced by the enhanced ratio of Bacteroides to Firmicutes, the decreased abundance of pathogenic bacteria (including Bacteroides, Alistipes, Blautia, and Colidextribacter) and the increased abundance of beneficial bacteria (including Muribaculaceae, Akkermansia, Faecalibaculum, and Rikenellaceae_RC9_gut_group). LP-HF02 also increased fecal short-chain fatty acids (SCFAs) levels and colonic mucosal thickness, and subsequently decreased serum lipopolysaccharide (LPS), interleukin-1β (IL-1β), and tumor necrosis factor-α (TNF-α) levels in obese mice. Additionally, reverse transcription quantitative polymerase chain reaction (RT-qPCR) and Western blot results demonstrated that LP-HF02 ameliorated hepatic lipid accumulation via activating the adenosine monophosphate (AMP)-activated protein kinase (AMPK) pathway.

CONCLUSION

Therefore, our results indicated that LP-HF02 could be considered as a probiotic preparation for preventing obesity. © 2023 Society of Chemical Industry.

Effects of supplementation of tropical fruit processing by-products on lipid profile, retinol levels and intestinal function in Wistar rats

Fruits agro-industrial by-products may have a great variety of bioactive compounds that promote health. Thus, the effects of supplementation with acerola, cashew and guava processing by-products for 28 days on retinol level, lipid profile and on some aspects related to intestinal function in rats were investigated. The animals supplemented with different fruit by-products presented similar weight gain, faecal pH values and intestinal epithelial structures; however, they showed higher moisture and Lactobacillus spp. and Bifidobacterium spp. counts in faeces compared to the control group. Supplementation with the cashew by-product decreased the blood glucose, acerola and guava by-products reduced serum lipid levels and all fruit by-products tested increased serum and hepatic retinol. The results indicated that acerola and guava by-products possess a potential hypolipidemic effect. The three fruit by-products increase the hepatic retinol deposition and the faecal populations of beneficial bacterial groups and modulated aspects of intestinal function. The findings of this study can contribute to sustainable fruticulture and support future clinical studies with the supplementation of by-products.

Locust Bean Gum, a Vegetable Hydrocolloid with Industrial and Biopharmaceutical Applications

Locust bean gum (LBG), a vegetable galactomannan extracted from carob tree seeds, is extensively used in the food industry as a thickening agent (E410). Its molecular conformation in aqueous solutions determines its solubility and rheological performance. LBG is an interesting polysaccharide also because of its synergistic behavior with other biopolymers (xanthan gum, carrageenan, etc.). In addition, this hydrocolloid is easily modified by derivatization or crosslinking. These LBG-related products, besides their applications in the food industry, can be used as encapsulation and drug delivery devices, packaging materials, batteries, and catalyst supports, among other biopharmaceutical and industrial uses. As the new derivatized or crosslinked polymers based on LBG are mainly biodegradable and non-toxic, the use of this polysaccharide (by itself or combined with other biopolymers) will contribute to generating greener products, considering the origin of raw materials used, the modification procedures selected and the final destination of the products.

Carob Extract Supplementation Together with Caloric Restriction and Aerobic Training Accelerates the Recovery of Cardiometabolic Health in Mice with Metabolic Syndrome

Carob, the fruit of Ceratonia siliqua L. exerts antidiabetic, anti-inflammatory, and antioxidant effects and could be a useful strategy for the treatment and/or prevention of metabolic syndrome (MetS). The aim of this study was to analyze whether supplementation with a carob fruit extract (CSAT+®), alone or in combination with aerobic training, accelerates the recovery of cardiometabolic health in mice with MetS subjected to a caloric restriction. For this purpose, mice were fed with a high fat (58% kcal from fat)/high sugar diet for 23 weeks to induce MetS. During the next two weeks, mice with MetS were switched to a diet with a lower caloric content (25% kcal from fat) supplemented or not with CSAT+® (4.8%) and/or subjected to aerobic training. Both caloric reduction and aerobic training improved the lipid profile and attenuated MetS-induced insulin resistance measured as HOMA-IR. However, only supplementation with CSAT+® enhanced body weight loss, increased the circulating levels of adiponectin, and lowered the plasma levels of IL-6. Moreover, CSAT+® supplementation was the only effective strategy to reduce the weight of epidydimal adipose tissue and to improve insulin sensitivity in the liver and in skeletal muscle. Although all interventions improved endothelial function in aorta segments, only supplementation with CSAT+® reduced obesity-induced hypertension, prevented endothelial dysfunction in mesenteric arteries, and decreased the vascular response of aorta segments to the vasoconstrictor AngII. The beneficial cardiometabolic effects of CSAT+® supplementation, alone or in combination with aerobic training, were associated with decreased mRNA levels of pro-inflammatory markers such as MCP-1, TNFα, IL-1β, and IL-6 and with increased gene expression of antioxidant enzymes, such as GSR, GPX-3, and SOD-1 in the liver, gastrocnemius, retroperitoneal adipose tissue, and aorta. In conclusion, supplementation with CSAT+®, alone or in combination with aerobic training, to mice with MetS subjected to caloric restriction for two weeks enhances body weight loss, improves the lipid profile and insulin sensitivity, and exerts antihypertensive effects through its anti-inflammatory and antioxidant properties.

Carob: A Sustainable Opportunity for Metabolic Health

Carob (Ceratonia siliqua L.) is an evergreen tree that belongs to the Leguminosae family and grows in the arid and semi-arid regions of the Mediterranean basin. The carob tree is resistant to droughts and salinity, while its deep root systems allow CO₂ to sink, mitigating global warming effects. Traditionally, carob has been used to produce animal feed, but for many years, it was excluded from the human diet. Nowadays, agricultural and industrial sectors exploit carob fruit, also referred to as carob pod, and its primary products (i.e., flour, powder and syrup) to develop a variety of foods and beverages. The nutritional composition varies depending on the carob part but also on genetic, cultivar, seasonal and environmental factors. Despite the high sugar content, the carob pod is rich in insoluble fiber and microconstituents including phenolic compounds, inositols (mainly d-pinitol) and vitamins. In the present review article, we aimed to (a) highlight the role of carob cultivation in addressing climate change challenges and the need for sustainability, and (b) summarize the effects of carob consumption on obesity and related metabolic disorders.

Lipid-Lowering Effects of Carob Extracts (Ceratonia siliqua): Proposed Mechanisms and Clinical Importance

The global prevalence of dyslipidemia (elevated plasma levels of total cholesterol, LDL-Cholesterol, triglycerides, and lower plasma levels of HDL-Cholesterol) is constantly on the rise. Lately, carob pulp has been recognized as an effective natural product for the treatment of dyslipidemia. The two main components of the carob pulp, polyphenols, and insoluble fiber are believed to have beneficial effects on lipid metabolism. Studies on humans and animals confirmed its lipid-lowering effects. Several mechanisms have been proposed to explain this phenomenon, namely by affecting three organ systems: 1) gastrointestinal tract, 2) liver and 3) adipose tissue. Also, carob products have antioxidative, anti-inflammatory, and vascular-protective activity.

Compositional, Structural, and Kinetic Aspects of Lipid Digestion and Bioavailability: In Vitro, In Vivo, and Modeling Approaches

Lipid digestion and bioavailability are usually investigated separately, using different approaches (in vitro, modeling, in vivo). However, a few inclusive studies show that their kinetics are closely linked. Lipid bioavailability kinetics is likely involved in the development and evolution of several diseases, so lipid digestion kinetics could be involved as well and can be modulated by food design or combination. To illustrate this possibility, the compositional and structural aspects of lipid digestion kinetics, as investigated using in vitro and modeling approaches, are presented first. Then, in vivo and mixed approaches enabling the study of both kinetics are reviewed and discussed. Finally, disparate modeling approaches are introduced, and a unifying modeling scheme is proposed, opening new perspectives for understanding the role and interactions of various factors (chemical, physical, and biological) involved in lipid metabolism.

Expected final online publication date for the Annual Review of Food Science and Technology, Volume 13 is March 2022. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.

Characterization of insoluble dietary fiber from three food sources and their potential hypoglycemic and hypolipidemic effects

Dietary fiber is an important nutrient for improving human health and controlling calorie intake, and is used to produce functional foods. In this study, insoluble dietary fiber (IDF) from three sources (enoki mushrooms, carrots, and oats) was characterized and their hypoglycemic and hypolipidemic effects were determined with in vitro and in vivo models. The results of Scanning electron microscopy (SEM) showed that the IDF from the three sources have different morphologies. The Fourier transform infrared spectroscopy (FT-IR) results showed that the IDF samples from the three sources have similar active groups, but the X-ray diffraction (XRD) and thermogravimetric analysis/differential scanning calorimetry (TGA/DSC) results indicated that oat IDF mainly contained cellulose, and enoki mushroom IDF and carrot IDF contained hemicelluloses and cellulose. Among three IDF, carrot IDF had stronger water holding capacity, swelling capacity, and adsorption capacity of oil and cholate; enoki mushroom IDF had stronger glucose adsorption capacity and the ability to inhibit fat digestion; while oat IDF had stronger cholesterol adsorption capacity. None of the three IDF showed significant inhibition on starch digestion. Results from mouse feeding studies showed that IDF from three sources all improved glucose tolerance and inhibited the rise of blood lipid after the fat loading. Thus, this study demonstrated the functional significance of the IDF from three sources, which provides a reference for their application in functional food products aiming at maintaining healthy glucose and blood lipid levels.

Carob fruit extract-enriched meat, as preventive and curative treatments, improves gut microbiota and colonic barrier integrity in a late-stage T2DM model

Epidemiological and experimental studies have suggested that dietary fiber and proanthocyanidins play an important role on gut microbiota (GM), colonic integrity and body health. Type 2 Diabetes Mellitus (T2DM) is a prevalent disease in which the modifications in the GM and colonic markers stand out. This manuscript hypothesizes the consumption of functional meat enriched in carob fruit extract [CFE; CFE-restructured meat (RM)] ameliorates the dysbiosis and colonic barrier integrity loss in a late-stage T2DM rat model induced by the conjoint action of a high-saturated-fat/high-cholesterol diet (Chol-diet) and a low dose of streptozotocin (STZ) plus a nicotinamide (NAD) injection. Three groups of eight rats were used: (1) D group, a T2DM control group, fed the Chol-diet; (2) ED group, a T2DM preventive strategy group fed the CFE-Chol-diet since the beginning of the study; and (3) DE group, a T2DM curative treatment group, fed the CFE-Chol-diet once the diabetic state was confirmed. The study lasted 8 weeks. Amount and variety of GM, feces short-chain-fatty acids (SCFAs), colonic morphology [crypt depth and density, goblet cells, proliferating cell nuclear antigen (PCNA) and transferase dUTP nick end labelling (TUNEL) indexes] and tight junctions were evaluated. A global colonic index combining 17 markers (GC_index) was calculated. ED rats displayed higher levels of GM richness, SCFAs production, crypt depth, and goblet cells than the D group. DE group showed lower Enterobacteriaceae abundance and greater TUNEL index and occludin expression in the distal colon than D counterpart. GC_index differentiated the colonic health status of the experimental groups in the order (ED > DE > D; P < 0.001) as a 17-51 range-quotation, ED, DE, and D groups displayed the values 43, 32.5, and 27, respectively. Thus, CFE-RM used as a T2DM preventive therapy could induce higher GM richness, more adequate SCFAs production, and better colonic barrier integrity. Furthermore, CFE-RM used with curative purposes induced more modest changes and mainly at the distal colonic mucosa. Further studies are needed to confirm this study's results, to ascertain the benefits of consuming proanthocyanidins-rich fiber during different T2DM stages.

The Effect of Emulsifying Protein and Addition of Condensed Tannins on n-3 PUFA Enriched Emulsions for Functional Foods

This paper examines the effect of the type of the emulsifying protein (EP) (sodium caseinate (SC) and whey protein isolate (WPI)) on both oil-in-water liquid-like emulsions (Es) and the corresponding cold gelled emulsions (GEs), and also the effect of addition of carob extract rich in condensed tannins (T). The systems, intended as functional food ingredients, were studied in various different respects, including rheological behaviour, in vitro gastrointestinal digestion with determination of the release of non-extractable proanthocyanidins (NEPA) from T, antioxidant activity and lipolysis. EP significantly affects the rheological behaviour of both Es and GEs. T incorporation produced a structural reinforcement of GEs, especially in the case of SC. The digests from Es displayed a higher antioxidant activity than those from GEs. T lipase inhibition was observed only in the formulations with WPI. Our results highlight the importance, in the design of functional foods, of analyzing different variables when incorporating a bioactive compound into a food or emulsion in order to select the better combination for the desired objective, owing to the complex interplay of the various components.

Protective effects of Ceratonia siliqua extract on protamine gene expression, testicular function, and testicular histology in doxorubicin-treated adult rats: An experimental study

BACKGROUND

Spermatogenesis is a complex process that takes place under the influence of many different genes.

OBJECTIVE

The aim of this study was to investigate the possible effects of Ceratonia siliqua hydroalcoholic extract (CSHAE) on protamine gene expression, testicular function, and testicular histology in doxorubicin-treated rats.

MATERIALS AND METHODS

56 adult male rats with a age range of 2.5 to 3 months (210 ± 10 gr) were divided into seven groups (n = 8/each). A) Control group was left untreated; B) Sham group received 0.3 ml distilled water intraperitoneally, C) Negative control group received 3 mg/kg doxorubicin, intraperitoneally once a week for 28 days; and D) Positive control group received 600 mg/kg of CSHAE orally for 48 days; E, F, G) the experimental groups 1, 2, and 3 received 150, 300, and 600 mg/kg of CSHAE respectively orally, for 48 days, as well as 3 mg/kg doxorubicin once a week for 28 days. Hematoxylin-eosin staining was used in the histological study of testes, and enzyme-linked immunosorbent assay method was used in measuring serum levels of testosterone. Protamine gene expression was determined by real-Time PCR method.

RESULTS

The mean body weight, testicular weight, testicular volume, testosterone level (p = 0.022), the count of Leydig, spermatogonia, spermatocyte, and spermatid cells, as well as protamine gene expression (p = 0.008) were significantly increased in the experimental group 2 compared to the negative control group. The regeneration of testicular tissue was observed in the experimental group 2.

CONCLUSION

CSHAE has protective effect on doxorubicin-induced testicular injuries.

Carob fruit extract-enriched meat improves pancreatic beta-cell dysfunction, hepatic insulin signaling and lipogenesis in late-stage type 2 diabetes mellitus model

The inclusion of functional bioactive compounds of dietary fiber in meat products has been demonstrated to exert a significant impact on human health. Carob fruit extract (CFE) is a dietary fiber rich in proanthocyanidins with known antioxidant, hypolipidemic and hypoglycemic effects. Consumption of CFE-enriched meat (CFE-RM) may provide interesting benefits in late-stage type 2 diabetes mellitus (T2DM). To explore the antidiabetic mechanisms of CFE-RM, we used a model of late-stage T2DM in Wistar rats fed a high-saturated-fat/high-cholesterol diet (Chol-diet) and injected streptozotocin plus nicotinamide (D group). The effects of CFE-RM were tested by incorporating it into the diet as preventive strategy (ED group) or curative treatment (DE group). CFE-RM had a positive effect on glycemia, enhancing hepatic insulin sensitivity and improving pancreatic β-cell regeneration in both ED and DE groups. Western blotting and immunohistochemistry suggested that CFE-RM increased levels of insulin receptor β and phosphatidylinositol-3-kinase, as well as the downstream target phospho-Akt (at Ser⁴⁷³). CFE-RM also up-regulated glucose transporter 2, which improves the insulin-mediated glucose uptake by the liver, and promoted phosphorylation of glycogen synthesis kinase-3βprotein (at ser⁹), consequently increasing the hepatic glycogen content. In addition, CFE-RM decreased fatty liver by suppressing de novo lipogenesis activation due to down-regulation of liver X receptor-α/β, sterol regulatory element binding protein-1c and carbohydrate-response element-binding protein transcription factors. Our findings suggest that the consumption of CFE-RM included in the diet as a functional food should be considered as a suitable nutritional strategy to prevent or manage late-stage T2DM.

Supplementation with a Carob (Ceratonia siliqua L.) Fruit Extract Attenuates the Cardiometabolic Alterations Associated with Metabolic Syndrome in Mice

The incidence of metabolic syndrome (MetS) is increasing worldwide which makes necessary the finding of new strategies to treat and/or prevent it. The aim of this study was to analyze the possible beneficial effects of a carob fruit extract (CSAT+^®) on the cardiometabolic alterations associated with MetS in mice. 16-week-old C57BL/6J male mice were fed for 26 weeks either with a standard diet (chow) or with a diet rich in fats and sugars (HFHS), supplemented or not with 4.8% of CSAT+^®. CSAT+^® supplementation reduced blood glucose, Homeostatic Model Assessment of Insulin Resistance (HOMA-IR) and circulating levels of total cholesterol, low-density lipoprotein (LDL) cholesterol (LDL-c), insulin, and interleukin-6 (IL-6). In adipose tissue and skeletal muscle, CSAT+^® prevented MetS-induced insulin resistance, reduced macrophage infiltration and the expression of pro-inflammatory markers, and up-regulated the mRNA levels of antioxidant markers. Supplementation with CSAT+^® prevented MetS-induced hypertension and decreased the vascular response of aortic rings to angiotensin II (AngII). Moreover, treatment with CSAT+^® attenuated endothelial dysfunction and increased vascular sensitivity to insulin. In the heart, CSAT+^® supplementation reduced cardiomyocyte apoptosis and prevented ischemia-reperfusion-induced decrease in cardiac contractility. The beneficial effects at the cardiovascular level were associated with a lower expression of pro-inflammatory and pro-oxidant markers in aortic and cardiac tissues.

Functional polysaccharides of carob fruit: a review

Polysaccharides in carob fruit, including carob bean gum (also known as carob gum, locust bean gum) and carob fiber, are widely used in industries such as food, pharmaceuticals, paper, textile, oil well drilling and cosmetics. Carob bean gum is a galactomannan obtained from the seed endosperm of carob tree and the fiber is obtained by removing most of soluble carbohydrates in carob pulp by water extraction. Both the gum and fiber are beneficial to health for many diseases such as diabetes, bowel movements, heart disease and colon cancer. This article reviewed the composition, properties, food applications and health benefits of polysaccharides from carob fruit.

Can Carob-Fruit-Extract-Enriched Meat Improve the Lipoprotein Profile, VLDL-Oxidation, and LDL Receptor Levels Induced by an Atherogenic Diet in STZ-NAD-Diabetic Rats?

Carob fruit extract (CFE) has shown remarkable in vitro antioxidant properties and reduces postprandial hyperglycemia and hyperlipidemia in healthy animals. Development of functional meat products that contain bioactive components are presented as a great nutritional strategy. Until now, the effect of the consumption of restructured meat enriched with CFE in a murine model of diabetes has not been investigated. The objective of this study was to evaluate the effect on glycemia, lipemia, lipoprotein profile, Ldlr, arylesterase (AE), and very low-density lipoproteins (VLDL) and liver oxidation in streptozotocin-nicotinamide (STZ-NAD) growing Wistar diabetic rats fed restructured meat in the frame of a high cholesterol/high saturated-fat diet. In the present study, three groups (D, ED and DE) were fed cholesterol-enriched (1.4% cholesterol and 0.2% cholic acid) and high saturated-fat diets (50% of total energy from fats and 20.4% from saturated fatty acids). Rats were subjected to a STZ-NAD administration at the 3rd week. Group D did not receive CFE, while ED and DE rat groups received CFE before and after the diabetic induction, respectively. After eight weeks, D rats showed hyperglycemia and hypercholesterolemia, an increased amount cholesterol-enriched VLDL (β-VLDL), IDL and LDL particles and triglyceride-enriched HDL. ED and DE partially blocked the hypercholesterolemic induction with respect to D group (p < 0.001) and improved glycemia, cholesterol levels, lipoprotein profile, Ldlr, plasma AE activity and liver oxidation (p < 0.001). Fecal fat, moisture and excretion were higher while dietary digestibility was lower in ED and DE vs. D counterparts (p < 0.0014). In conclusion, CFE-enriched meat shows, for the first time, hypoglycemic and hypolipidemic effects in STZ-NAD animals fed high cholesterol/high saturated-fat diets. Likewise, it manages to reverse possible diabetes lipoprotein alterations if CFE-enriched meat is consumed before pathology development or improves said modifications if Type 2 Diabetes Mellitus is already established.