Carob: A Sustainable Opportunity for Metabolic Health

Prebiotic potential of Ceratonia siliqua polysaccharides: Ultrasound-assisted extraction enhances gut microbial diversity and metabolic activity

Ultrasound-assisted extraction was optimized for efficient recovery of plant-based polysaccharides from Ceratonia siliqua pulp. The extracted polysaccharide underwent purification via deproteinization, dialysis, and DEAE-52 ion exchange chromatography, yielding UPS-3, a monodispersed polymer (Mw 1.3 × 103 kDa) composed of mannose, glucuronic acid, glucose, xylose, arabinose, and galactose. UPS-3 exhibited potent antioxidant properties, confirmed by DPPH, ABTS, FRAP, RP, and TAC assays, along with significant α-amylase (98.2 %) and α-glucosidase (95.1 %) inhibition at 2000 μg/mL, highlighting its anti-diabetic potential. Additionally, UPS-3 displayed in vitro anticancer activity against Caco-2 cells and exhibited antibacterial effects against common pathogens. Its prebiotic properties were evidenced by the selective promotion of beneficial gut microbial taxa belonging to the classes Clostridia, Actinobacteria, and Bacteroidia, while inhibiting the potentially pathogenic organisms such as Escherichia and Klebsiella. Fecal fermentation analysis revealed increased production of short-chain fatty acids (SCFAs), including acetate, propionate, and butyrate, emphasizing its role in gut health. Rheological analysis showed its potential as a functional food ingredient with excellent water and oil-holding capacities. These findings suggest that UPS-3 could serve as a natural therapeutic agent for managing metabolic disorders and promoting gut health.

Carob (Ceratonia siliqua) leaves: A comprehensive analysis of bioactive profile and health-promoting potential of an untapped resource

Carob is a resilient plant with ecological and nutritional significance. A comprehensive study of Ceratonia siliqua leaves (CSL) was conducted to explore its chemical composition and health-promoting potential, aiming at improving the carob-crop sustainability through valorization of this untapped co-product. UHPLC-DAD-HRMS/MS quali-quantitative profiling of CSL revealed high levels of n-galloylated glucoses (129-196 mg g-1) and flavonol-glycosides (36-42 mg g-1), with siliquapyranone (39-56 mg g-1), 1,2,3,6-tetragalloylglusose (47-69 mg g-1) and myricitrin (27-33 mg g-1) as main markers. Highest bioactive content and antioxidant capacity (5.0 and 3.1 TEAC) was obtained during pods harvesting. Besides significant antioxidant potential, CSL exhibited strong-high inhibitory activity against α-glucosidase, acetylcholinesterase and butyrylcholinesterase (IC50, 0.51, 13.5 and 58.0 μg mL-1, respectively). 1,2,3,6-tetragalloylglusose and siliquapyranone are the main contributors to antioxidant and α-glucosidase inhibitory capacities. Excellent ability of extract and 1,2,3,6-tetragalloylglusose (IC50, 0.05 μM) in selectively inhibiting α-glucosidase, make them promising candidates to manage hyperglycemia with fewer side effects.

Chemical composition, in vitro gas production, and nutrient degradability of carob leaves as a sustainable feed for ruminants in Tunisia and Palestine

Introduction

Carob leaves may be a potential roughage source for ruminants in arid areas. The nutritive value of this feedstuff may be considerably enhanced by the application of solid-phase chemical treatments. This study aimed to evaluate the nutritive value of carob leaves collected from Tunisia and Palestine untreated or treated with urea or sodium hydroxide (NaOH), or supplemented with polyethylene glycol (PEG) on chemical composition and in vitro ruminal fermentation.

Methods

Carob leaf samples were collected from either Palestine or Tunisia, and were used either untreated (control) or treated with urea, NaOH at 4% or PEG at 100 mg/g (dry matter (DM) basis), and analyzed for chemical composition. Carob leaves were incubated in vitro in diluted rumen fluid fermentation for 48 h, measuring fermentation gasses [methane (CH4), and carbon dioxide (CO2)], DM degradability and fermentation kinetics.

Results and discussion

Results showed a significant country × treatment interaction for most measured parameters, indicating that treatment effects are constrained by the origin of the leaves. Palestine untreated carob leaves had higher (p < 0.001) crude fat, crude protein (CP) and neutral detergent fiber (NDF), but less nonstructural carbohydrate (NSC), acid detergent fiber (ADF) and acid detergent lignin than Tunisia leaves. Tunisia carob leaves had higher concentration (p < 0.01) of flavonoids and tannins than leaves from Palestine. Of the three treatments tested, the addition of PEG increased (p < 0.01) the gas production during the incubation in diluted rumen fluid of carob leaves and this effect was greater with leaves from Palestine than with those from Tunisia. The other treatments had less noticeable effects, which were different when applied to the leaves from one or another country, given the significance of the interaction country × treatment detected for most of the variables studied. PEG, NaOH and urea treatments of carob leaves can be applied to enhance the ruminal fermentation and energy value of this feedstuff. However, the effects of these treatments are highly dependent on the parent material, and seem to be more effective when applied to a low digestible material.

The Unripe Carob Extract (Ceratonia siliqua L.) as a Potential Therapeutic Strategy to Fight Oxaliplatin-Induced Neuropathy

BACKGROUND

Oxaliplatin-induced neuropathy (OIN) is a severe painful condition that strongly affects the patient's quality of life and cannot be counteracted by the available drugs or adjuvants. Thus, several efforts are devoted to discovering substances that can revert or reduce OIN, including natural compounds. The carob tree, Ceratonia siliqua L., possesses several beneficial properties. However, its antalgic properties have not been substantially investigated and only a few investigations have been conducted on the unripe carob (up-CS) pods. Thus, the aims of this study were to evaluate for the first time the unripe variety of Apulian carob, chemically characterized and profiled as antioxidant potential of polyphenolic compounds as well as to investigate the ability of up-CS to reduce the neurotoxicity in a mouse model of oxaliplatin-induced neuropathic pain.

METHODS

By UHPLC-HRMS/MS analyses, 50 phenolic compounds, belonging mainly to n-galloylated glucoses and flavonoids were detected.

RESULTS

In a mouse model of oxaliplatin-induced neurotoxicity (2.4 mg/kg, 10 injections over two weeks), acute per os treatment with up-CS provoked a dose-dependent pain-relieving effect that completely counteracted oxaliplatin hypersensitivity at the dose of 200 mg/kg. Repeated oral administration of up-CS (100 mg/kg), concomitantly with oxaliplatin injection, exerted a protective effect against the development of thermal and mechanical allodynia. In addition, up-CS exerted a neuroprotective role against oxaliplatin-induced astrocytes activation in the spinal cord measured as GFAP-fluorescence intensity.

CONCLUSIONS

Overall, our study contributes to the knowledge on up-CS properties by highlighting its protective activity in the painful condition related to the administration of oxaliplatin.

Nutritional value, HPLC-DAD analysis and biological activities of Ceratonia siliqua L. pulp based on in vitro and in silico studies

The phytochemical, nutritional, and biological features of wild carob pulp from Tanzight (TN), Ait-Waada (AW), and Tizi-ghnayn (TG) in Azilal were studied. The results of the study reveal that the carob pulp examined has a low-fat level. AW had the most total sugar (78.34 ± 3.00%), total reducing sugar (27.20 ± 2.89%), crude fiber (14.21 ± 1.23%), sucrose (24.303 ± 0.038%), sodium (153.7 ± 18.52 mg/kg), pH (5.599 ± 0.05), and total polyphenol content (4134.50 ± 17.91 mg GAE/100 g DW). TG has higher amounts of potassium (11373 ± 153.7 mg/kg), calcium (4345 ± 7.211 mg/kg), phosphorus (3551 ± 175.1 mg/kg), magnesium (1347 ± 52.43 mg/kg), fructose (7.635 ± 0.012%), and total flavonoids (1678.08 ± 24.05 mg RE/100 g DW). TN has the highest levels of crude protein (5.607 ± 0.047%), moisture (9.33 ± 0.57%), ash (4.16 ± 0.02%), glucose (2.956 ± 0.047%), and total condensed tannins (529.61 ± 6.76 mg CE/100 g DW). The ethanol extract derived from AW exhibited noteworthy antioxidant activity, as evidenced by its total antioxidant capacity (TAC) of 1245.83 ± 26.33 µg ascorbic acid equivalent /mg extract and IC50 values of 18.45 ± 1.41 µg/mL, 124.98 ± 5.21 µg/mL, and 24.87 ± 1.30 µmol/mL for 2,2-Diphenyl-1-picrylhydrazil (DPPH), beta carotene (β-Carotene), and 2,2'-azino-bis (3-éthylbenzothiazoline-6-sulfonate) (ABTS), respectively. Furthermore, AW has demonstrated significant antibacterial activity against a variety of bacterial and fungal strains using disc diffusion and broth dilution techniques. The analysed samples also demonstrated encouraging anti-cancer effects on MDA-MB-231, MDA-MB-436, and MCF-7 cancer cell lines. The biological activities were confirmed through molecular docking analysis, identifying naringin and quercetin 3-O-β-glucoside as related compounds. Additionally, ADME analyses have revealed that all the synthetic compounds examined in this study demonstrate high intestinal absorption, meet Lipinski's criteria, indicating their potential suitability for oral drug development. Based on these findings, wild carob pulp from Azilal province may contain bioactive compounds and nutrients.

Carob Syrup: Prebiotic Potential of a Neglected Functional Beverage of Mediterranean Countries

Carob syrup, a traditional Mediterranean functional beverage obtained from Ceratonia siliqua (L.) pods, has been historically valued for its nutritional properties but is currently underutilized. This study compared the prebiotic potential of three handmade carob syrups produced by Tunisian women with commercial benchmarks from Italy, Greece and Cyprus. The prebiotic activity was evaluated by prebiotic scores, bifidogenic activity and volatilome characterization (SPME GC/MS) together with physicochemical and nutritional parameters. The results showed that Tunisian handmade products exhibited lower growth of pathogenic Escherichia coli compared to commercial samples. The prebiotic activity, tested against probiotic lactobacilli and bifidobacteria mixtures, showed a hierarchy of efficacy: fructo-oligosaccharides (FOSs) > Tunisian handmade products > Greek and Cypriot benchmarks > Italian benchmark. Volatilome analysis revealed about 40 compounds, mainly organic acids and aldehydes, with higher concentrations in handmade products. Positive correlations were found between prebiotic activity and short-chain fatty acids and n-hexadecanoic acid, while furfural showed negative correlations. The Tunisian artisanal products showed a higher prebiotic potential compared to the commercial counterparts, due to their higher content and diversity of organic acids. However, the presence of furfural in Tunisian products needs to be monitored due to potential toxicity concerns.

Enhancing antioxidant yield from carob (Ceratonia siliqua L.): evaluating the efficacy of maceration and ultrasound-assisted methods

  Our study aimed to optimize carob antioxidant extraction for use in the food, cosmetic, and pharmaceutical industries. Maceration investigated ethanol concentration, extraction temperature, and time, while ultrasound-assisted extraction examined ethanol concentration, ultrasound power, and time. A central composite design with 19 experimental points assessed the influence of variables on total yield, total phenolic content, and antioxidant activity. The results were analyzed to optimize the extraction parameters and enhance the antioxidant extraction from carob. The results of the study show that the best maceration condition for extracting antioxidants from the plant material was found to have a time of 24.38 minutes, an ethanol content of 59.02%, and a temperature of 54.52°C. Similarly, the optimal conditions for ultrasound-assisted extraction were found to be 51.49 minutes, 79.78% sonication power, and 76.12% alcohol. The optimal conditions identified can be used as a starting point for further optimization and scaling up of the extraction process.

Carob (Ceratonia siliqua) Flour as Source of Bioactive Compounds: Production, Characterization and Nutraceutical Value

Carob (Ceratonia siliqua) seeds are rich in diverse bioactive compounds, including galactomannan, β-sitosterol, unsaturated fatty acids and proteins with bioactive peptides in their sequence. This study delineates the compositional characterization of six carob seed flour types derived from different production processes, providing valuable insights for designing tailored nutraceutical products based on desired bioactive compound profiles. Our analysis indicated that a higher purity of galactomannan resulted in a greater mannose/galactose ratio, which increased the linearity of the galactomannan polymer and could enhance interchain interaction, thereby increasing aggregation capacity. A higher viscosity could potentially increase the capacity of galactomannan to create satiety and lower cholesterol levels. Among the different tested flours, those whose main compound was the endosperm were optimal for containing high galactomannan content, whereas those derived from the germ were ideal for having high concentrations of fatty acids (i.e., oleic and linoleic acids) and β-sitosterol. The presence of these lipids in carob flours could offer cardiovascular and metabolic health benefits, contributing synergistically. Additionally, flours that contain the germ have beneficial peptides included in proteins like glycinin and conglutin with potential anticholesterolemic and antidiabetic properties. This work provides different methods for obtaining carob flours rich in bioactive compounds, offering the nutraceutical industry a framework to select the best option for industrial-scale production.

Sensory Evaluation and Consumers' Acceptance of a Low Glycemic and Gluten-Free Carob-Based Bakery Product

Carob pulp flour has antidiabetic and antioxidant activities, is naturally sweet, and is rich in fibers. It is obtained from carob pod pulp from the evergreen tree Ceratonia siliqua L., which is grown in Mediterranean areas and is known for locust bean gum production. Despite its valuable effects on health, such as the modulation of the glycemic index, this ingredient has a tremendous impact on technological and hedonic features, mainly on color, flavor, and texture. In this paper, the qualitative features and consumers' acceptance of a carob-based gluten-free bakery product where rice flour was substituted at 40% with carob pulp flour were studied. A panel group of experts described the bread as dark, quite dense, sweet, aromatic, and with a limited bubble dispersion. On the other hand, the sensory assessment and the willingness to pay of consumers were assessed in two groups (a fully informed one about heathy attributes of the food and a blind one). The results indicated a moderate appreciation of the overall quality of the product (average score between 4 and 5 points on a 9-point Likert scale). The information about the food's healthy properties and the ability to maintain a low glycemic index did not enhance the consumers' perception of the product, while previous knowledge and involvement in the product consumption were perceived to have primary importance regarding the final consumers' choice. Finally, an accelerated shelf-life test was run on the packaged snack to evaluate the general quality and stability. The protective packaging helped in limiting bread decay and maintaining the textural characteristics.

Identification, Bioaccessibility, and Antioxidant Properties of Phenolic Compounds in Carob Syrup

Carob syrup is a brown, thick syrup produced from carob pulp that can be directly consumed or used as a sweetener, which also finds applications in folk medicinal practices. In this work, the quali-quantitative phenolic profile of five different carob syrups was elucidated before and after in vitro gastro-intestinal digestion. Moreover, the anti-oxidant properties of undigested and digested carob syrups were investigated. A total of 75 phenolic compounds were identified in undigested carob syrups. The most important phenolic compound in all the samples was gallic acid, the concentration of which ranged between 54.28 and 117.73 mg/100 g. Additional compounds belonging to the classes of hydroxybenzoic acids (in particular glycosylated gallic acid derivatives), hydroxycinnamic acids, and flavonoids (especially flavonols) were also identified. During in vitro gastric digestion, gallic acid mono- and di-hexosides were diglycosylated, releasing gallic acid, which was further degraded in ellagic acid through oxidative polymerization in the intestinal phase of the digestion. Ellagic acid was the major compound detected after in vitro gastro-intestinal digestion of carob syrups. With few exceptions, the anti-oxidant properties of carob syrup were preserved even after digestion. Carob syrup can be considered an important source of phenolic compounds with demonstrated positive effects on human health.

Carob: A Mediterranean Resource for the Future

For centuries, the carob tree (Ceratonia siliqua L.) has contributed to the economy of the Mediterranean basin, mainly as food for livestock. Nowadays, the value of the carob tree extends far beyond its traditional uses, encompassing a wide range of industries and applications that take advantage of its unique properties and nutritional benefits. Despite its high industrial demand and European indications, there has been a 65% reduction in the area cultivated throughout the Mediterranean area in the 21st century. Given the threats posed by climate change, including reduced water availability and nutrient-depleted soils, there is a growing need to focus on this crop, which is well placed to cope with unpredictable weather. In this review, we use a bibliographic search approach to emphasise the prioritisation of research needs for effective carob tree exploitation. We found enormous gaps in the scientific knowledge of this under-utilised crop species with fruit pulp and seeds of high industrial value. Insufficient understanding of the biology of the species, as well as inadequate agronomic practices, compromise the quantity and the quality of fruits available to the industry. In addition to industrial applications, carob can also be used in reforestation or restoration programmes, providing a valuable crop while promoting biodiversity conservation and soil restoration. The carbon sequestration potential of the trees should be taken into account as a promising alternative in fighting climate change. This bibliographic search has highlighted clusters with different knowledge gaps that require further research and investment. The carob tree has untapped potential for innovation, economic development, and environmental sustainability.

Nutritional profiling, fiber content and in vitro bioactivities of wheat-based biscuits formulated with novel ingredients

This study evaluated the nutritional profile and fiber content of innovative formulations of wheat-based biscuits enriched with chia seeds, carob flour and coconut sugar. The in vitro antioxidant, cytotoxic, anti-inflammatory and antimicrobial activities were also investigated to understand the potential health advantages of the incorporation of these new ingredients. The novel biscuits demonstrated significant improvements in protein and mineral content, with increases of 50% and 100% in chia biscuits, and up to 20% and 40% in carob biscuits, respectively. Fiber also notably increased, particularly in samples containing 10% carob flour, which increased four times as compared to wheat-based samples. The new ingredients exhibited antibacterial and antifungal activity, particularly against Yersinia enterocolitica (minimum inhibitory concentration 1.25 mg mL-1 in coconut sugar) and Aspergillus fumigatus (minimum inhibitory concentration/minimum fungicidal concentrations 2.5/5 mg mL-1 in chia seeds). However, the final biscuits only displayed antifungal properties. Carob flour and chia seeds had a remarkably high capacity to inhibit the formation of TBARS and promoted greater antioxidant activity in biscuit formulations, with EC50 values decreasing from 23.25 mg mL-1 (control) to 4.54 mg mL-1 (15% defatted ground chia seeds) and 1.19 mg mL-1 (10% carob flour). Only chia seeds exhibited cellular antioxidant, anti-inflammatory and cytotoxic activity, attributes that were lost when seeds were added into the biscuits. These findings highlight the potential health benefits of these ingredients, particularly when incorporated in new wheat-based formulations.

Eco-friendly extraction of antibacterial compounds from enriched olive pomace: a design-of-experiments approach to sustainability

The increasing interest in utilizing olive pomace bioactive molecules to advance functional elements and produce antioxidant and antimicrobial additives underscores the need for eco-friendly extraction and purification methods. This study aims to develop an eco-friendly extraction method to evaluate the effect of extraction parameters on the recovery of bioactive molecules from enriched olive pomace. The effects were identified based on total phenolic and flavonoid contents and antioxidant activity, employing a design of experimental methodology. The positive and the negative simultaneous effects showed that among the tested enrichments, those incorporating Nigella Sativa, dates, and coffee demonstrated superior results in terms of the measured responses. Furthermore, chromatographic analysis unveiled the existence of intriguing compounds such as hydroxytyrosol, tyrosol, and squalene in distinct proportions. Beyond this, our study delved into the structural composition of the enriched pomace through FTIR analysis, providing valuable insights into the functional groups and chemical bonds present. Concurrently, antimicrobial assays demonstrated the potent inhibitory effects of these enriched extracts against various microorganisms, underscoring their potential applications in food preservation and safety. These findings highlight enriched olive pomace as a valuable reservoir of bioactive molecules for food products since they can enhance their anti-oxidative activity and contribute to a sustainable circular economy model for olive oil industries.

Antioxidant Activity and Seasonal Variations in the Composition of Insoluble Fiber from the Cladodes of Opuntia ficus-indica (L.) Miller: Development of New Extraction Procedures to Improve Fiber Yield

Opuntia ficus-indica (L.) Miller is a plant belonging to the Cactaceae family adapted to live in environments characterized by long periods of drought and arid or desert climates. This plant is characterized by an aerial part composed of structures transformed by branches, called "cladodes", which are essential to reduce excessive perspiration of water and appear covered with thorns. The composition of the cladodes includes water, polysaccharides, fiber, proteins, vitamins, fatty acids, sterols, polyphenols, and minerals. The main purposes of this scientific work are (a) to compare the insoluble fiber (IF) extracted from the cladodes of O. ficus-indica belonging to the same plant but collected in different seasonal periods (winter and summer) and develop new extraction protocols that are able to improve the yield obtained and (b) evaluate the antioxidant potential of the fiber and study possible variations as a result of the extraction protocol chosen. The first objective was achieved (1) by measuring the amount of IF extracted from cladodes harvested in winter and summer (CW and CS, respectively) and (2) by modifying three variables involved in the fiber extraction protocol. To achieve the second objective, the following experiments were carried out: (1) measurement of the antioxidant potential of IF in CW and CS; (2) measurement of cellular reactive oxygen species; (3) measurement of the activity of some antioxidant enzymes; and (4) comparison of the polyphenol content in CW and CS. In conclusion, the results obtained showed that the IF extraction process can be improved, achieving a uniform yield regardless of seasonality; the antioxidant effect may vary depending on the extraction protocol.

Carob (Ceratonia siliqua L.), Pharmacological and Phytochemical Activities of Neglected Legume of the Mediterranean Basin, as Functional Food

Carob (Ceratonia siliqua L.) has been widely cultivated in different parts of the world, particularly in the Mediterranean region, and the tree belongs to the family Leguminosae. Several studies have indicated that carobs and their products can improve human health and help prevent different specific chronic diseases. Carob can considered as functional food due to its high content in dietary fibers, low-fat content, and high content of minerals. Its fruit is a pod containing 10%-20% seeds, and the pods consist of sugars, proteins, crude fibers, minerals, vitamins, polyphenols, vitamins, and lipids. In many countries in the Middle east, carob is mainly used to prepare as a traditional drink and some kinds of confectioneries. The powders can be utilized to prepare carob juice concentrate. The systematic review of documents from clinical trials and scientific societies dedicated to traditional medicine in China has been carried out. The goal of this review article is a survey of chemical compounds, and pharmaceutical benefits of carob, especially by considering traditional medicinal sciences. Moreover, clinical trials research promotes studies to highlight and focus on the scope of application of traditional medicinal science in the growing system of medicine.

Major Pathogens Affecting Carob in the Mediterranean Basin: Current Knowledge and Outlook in Italy

The main pathogens affecting the carob (Ceratonia siliqua) tree in the Mediterranean basin are described in this overview. The most widespread diseases periodically occurring in carob orchards are powdery mildew (Pseudoidium ceratoniae) and cercospora leaf spot (Pseudocercospora ceratoniae). The causal agents of "black leaf spots" (e.g., Pestalotiopsis, Phyllosticta and Septoria spp.) are responsible for symptoms similar to those previously mentioned for foliar diseases, but are reported in carob orchards at a negligible frequency. Likewise, canker and branch diebacks caused by fungal species belonging to Botryosphaeriaceae are almost never recorded. Among the rots of wood tissues that may compromise old carob specimens, "brown cubical rot" caused by Laetiporus sulphureus is the most widespread and recurrent issue; this pathogen is also well-known for producing edible fruit bodies that are appreciated for pharmaceutical and industrial purposes. On the other hand, "white rots" caused by Fomes and Ganoderma species are less common and reported for the first time in this review. Gall-like protuberances on twigs of uncertain aetiology or tumors on branches associated with Rhizobium radiobacter are described, although these symptoms are seldom detected, as they are also observed for necrotic leaf spots caused by Pseudomonas syringae pv. ciccaronei. A worldwide list of pathogens not yet recorded but at high risk of potential introduction in Italian carob-producing areas is also provided. Finally, concerns related to new phytopathogenic fungi vectored by the invasive Xylosandrus compactus ambrosia beetle are addressed. All the described pathogens could become limiting factors for carob production in the near future, because they could be favored by high-density orchards, the increasing global network of trade exchanges, and the high frequency at which extreme events related to climate change occur globally. Thus, symptoms and signs, causal agents, epidemiology, and, whenever applicable, recommendations for disease prevention and management are provided in this review.

Aridity Gradients Shape Intraspecific Variability of Morphological Traits in Native Ceratonia siliqua L. of Morocco

The carob tree (Ceratonia siliqua L.) is a significant fruit tree in the Mediterranean region with cultural, biological, and ecological importance. Despite its importance, intraspecific trait variability (ITV) in carob trees has been largely overlooked in previous studies. Understanding ITV and its relationship with environmental conditions is crucial for conservation and breeding programs. In this study, we investigated the variability of carob pod and seed-related traits across different ecological scales in 25 studied populations in Morocco. Significant differences in morphological traits were observed between carob populations at various ecological levels, and pod-related traits exhibited greater variability than seed traits. Correlation analysis revealed strong associations between carob morphological traits and environmental conditions, with altitude and aridity index playing an influential role. The aridity gradient was strongly related to changes in pod size, seed number, and size, as well as seed yield. Our findings highlight an important ITV reaching 45% at the intra-population level, 36.5% at the inter-geographic level, and 30% at the inter-population level. Overall, this study contributes valuable insights into the ecology and adaptation of carob trees, emphasizing the importance of considering intraspecific variability when studying this remarkable species. This knowledge is critical for addressing the challenges posed by climate change and human activities on the long-term survival and ecological functioning of carob populations.

Exploring Carob (Ceratonia siliqua L.): A Comprehensive Assessment of Its Characteristics, Ethnomedicinal Uses, Phytochemical Aspects, and Pharmacological Activities

The carob tree (Ceratonia siliqua L.) is currently considered one of the most valuable fruit and forest trees in various fields and sectors of activity. It is a versatile plant, belonging to the Fabaceae family. It is widely used in traditional medicine to treat many diseases such as diabetes, hypertension, and gastrointestinal disorders, given that all its parts (leaves, flowers, pods, seeds, wood, bark, and roots) are useful and hold value in many areas. Its importance has increased significantly in recent years. Originating from the Middle East, it is recognized for its ecological and industrial significance. Previous studies conducted on Ceratonia siliqua L. have revealed the presence of several compounds, including polyphenols, flavonoids, carbohydrates, minerals, and proteins. The carob tree demonstrates antihypertensive, antidepressant, anti-obesity, and antihyperglycemic activities. This plant is known for its medicinal and therapeutic virtues. Moreover, it is particularly interesting to consider the pharmacological activities of the major phytochemical compounds present in the different extracts of this plant, such as phenolic acids, for example, coumaric and gallic acids, as well as flavonoids such as kaempferol and quercetin. Therefore, this review aims to analyze some aspects of this plant, especially the taxonomy, cytogeography, traditional uses, phytochemical constituents, and pharmacological activities of Ceratonia siliqua L., in addition to its biological properties.

Biological Activities of Ceratonia siliqua Pod and Seed Extracts: A Comparative Analysis of Two Cretan Cultivars

Ceratonia siliqua L., commonly known as the carob tree, appears in most Mediterranean countries, often cultivated for the collection of its fruits to be used as food for humans and animals. This study was aimed at the phytochemical characterization of two common Cretan C. siliqua cultivars and the biological evaluation of deseeded pod and seed extracts regarding their putative use in cosmetics. Gas and liquid chromatographic techniques were used to assess their essential oil, fatty acid, and carbohydrate profiles. Cell-free assays, including free-radical scavenging; the inhibition of tyrosinase and collagenase; the blocking of advanced glycation end product (AGE) formation; along with assays in human skin fibroblast cultures, i.e., reactive oxygen species suppression, glutathione stimulation, and protection from oxidative stress and from ultraviolet (UVB) radiation, were also used. Extracts from both cultivars were found to possess antioxidant capacity, tyrosinase- and collagenase-inhibitory activities, an ability to block glucose-induced AGEs, and in certain cases, UVB absorbance and photoprotective activities. Seed extracts were in general more active, while the use of 30% aqueous methanol seemed to be more efficient than n-hexane for extraction. Serial partition of the most active extracts resulted in fractions with enriched biological activities. These properties make Cretan carob extracts and their fractions suitable candidates for use in cosmetics.

Poplar Propolis Improves Insulin Homeostasis in Non-Diabetic Insulin-Resistant Volunteers with Obesity: A Crossover Randomized Controlled Trial

Propolis, a natural resinous mixture rich in polyphenols, produced by bees from a variety of plant sources, has shown significant therapeutic effects and may prevent the development of certain chronic diseases like type 2 diabetes mellitus (T2DM). The objective of this study was to evaluate the effect of supplementation with standardized poplar propolis extract powder (PPEP) on insulin homeostasis in non-diabetic insulin-resistant volunteers with obesity. In this randomized, controlled, crossover trial, nine non-diabetic insulin-resistant volunteers with obesity, aged 49 ± 7 years, were subjected to two periods of supplementation (placebo and PPEP) for 3 months. Blood samples and anthropomorphic data were collected at baseline and at the end of each phase of the intervention. PPEP supplementation improved insulin sensitivity by significantly decreasing the percentage of insulin-resistant subjects and the insulin sensitivity Matsuda index (ISI-M). According to this study, supplementation with standardized PPEP for 3 months in non-diabetic insulin-resistant volunteers with obesity led to an improvement in insulin homeostasis by its effect on insulin resistance and secretion. This study suggests that poplar propolis has a preventive effect on the physiopathological mechanisms of T2DM and, therefore, that it can help to prevent the development of the disease.

Development of a Functional Acceptable Diabetic and Plant-Based Snack Bar Using Mushroom (Coprinus comatus) Powder

Consumers' growing concern about health and well-being has led to increased interest in functional foods. This research aims to evaluate the physicochemical and antioxidant properties of a functional plant-based (PB) snack bar enriched with Coprinus comatus powder. The snack bar formulations exhibited a wide range of flavor and textural characteristics. Two PB snack bars and four commercial bars were evaluated by a consumer panel of healthy volunteers (n = 20). The PB snack bar scored 'like extremely' on the 9-point hedonic scale. External preference mapping determined that sweetness, flavors, cohesiveness, gumminess, and adhesion had the greatest influence on consumer acceptability. Water content, ash, protein, fat, carbohydrate, reducing sugar, resistant starch, and dietary fiber were measured. Nutritional content was enhanced (omega 3, fiber and protein), and samples were shelf life stable (aw < 0.29; moisture content < 10%). In addition, the PB snack bar underwent simulated digestion according to the INFOGEST protocol, and from the comparative evaluation, the PB snack can be seen to control the post-prandial glycemic responses, as observed by the different degree of reducing sugars released via the matrix. The PB snack bar can be further functionally enhanced by the addition of their unique ingredients such as Coprinus comatus. Coprinus comatus powder is claimed to benefit glycemic control in diabetes and has attracted growing interest in terms of its potential use in natural products with possible health benefits.

Use of Selected Lactic Acid Bacteria and Carob Flour for the Production of a High-Fibre and "Clean Label" Plant-Based Yogurt-like Product

Carob, an underutilized crop with several ecological and economic advantages, was traditionally used as animal feed and excluded from the human diet. Yet, nowadays, its beneficial effects on health are making it an interesting candidate as a food ingredient. In this study, a carob-based yogurt-like product was designed and fermented with six lactic acid bacteria strains, whose performances after fermentation and during shelf life were assessed through microbial and biochemical characterization. The strains showed different aptitudes to ferment the rice-carob matrix. Particularly, Lactiplantibacillus plantarum T6B10 was among the strains with the lowest latency phase and highest acidification at the end of fermentation. T6B10 also showed discrete proteolysis during storage, so free amino acids were up to 3-fold higher compared to the beverages fermented with the other strains. Overall, fermentation resulted in the inhibition of spoilage microorganisms, while an increase in yeasts was found in the chemically acidified control. The yogurt-like product was characterized by high-fiber and low-fat content; moreover, compared to the control, fermentation decreased the predicted glycemic index (-9%) and improved the sensory acceptability. Thus, this work demonstrated that the combination of carob flour and fermentation with selected lactic acid bacteria strains represents a sustainable and effective option to obtain safe and nutritious yogurt-like products.

Ceratonia siliqua L. Pod Extract: From Phytochemical Characterization to Liposomal Formulation and Evaluation of Behaviour in Cells

The formulation of plant extracts in phospholipid vesicles is a promising strategy to exploit their biological properties while solving problems related to poor solubility in water, high instability, and low skin permeation and retention time. In this study, Ceratonia siliqua ripe pods were used for the preparation of a hydro-ethanolic extract, which showed antioxidant properties owing to the presence of biologically active compounds identified by liquid chromatography-mass spectrometry (e.g., hydroxybenzoic acid and flavonoid derivatives). To improve the applicability of the extract in therapy, a topical formulation based on liposomes was explored. The vesicles were characterized by small size (around 100 nm), negative charge (-13 mV), and high entrapment efficiency (>90%). Furthermore, they displayed both spherical and elongated shapes, with oligolamellar structure. Their biocompatibility was demonstrated in cells, including erythrocytes and representative skin cell lines. The antioxidant activity of the extract was proved by the scavenging of free radicals, the reduction of ferric ions, and the protection of skin cells from oxidative damage.

Optimization of Carob Products Preparation for Targeted LC-MS/MS Metabolomics Analysis

Carob (Ceratonia siliqua) is an exceptional source of significant bioactive compounds with great economic importance in the Mediterranean region, where it is widely cultivated. Carob fruit is used for the production of a variety of products and commodities such as powder, syrup, coffee, flour, cakes, and beverages. There is growing evidence of the beneficial effects of carob and the products made from it on a range of health problems. Therefore, metabolomics could be used to explore the nutrient-rich compounds of carob. Sample preparation is a crucial step in metabolomics-based analysis and has a great impact on the quality of the data obtained. Herein, sample preparation of carob syrup and powder was optimized, to enable highly efficient metabolomics-based HILIC-MS/MS analysis. Pooled powder and syrup samples were extracted under different conditions by adjusting pH, solvent type, and sample weight to solvent volume ratio (Wc/Vs). The metabolomics profiles obtained were evaluated using the established criteria of total area and number of maxima. It was observed that the Wc/Vs ratio of 1:2 resulted in the highest number of metabolites, regardless of solvent type or pH. Aqueous acetonitrile with a Wc/Vs ratio of 1:2 satisfied all established criteria for both carob syrup and powder samples. However, when the pH was adjusted, basic aqueous propanol 1:2 Wc/Vs and acidic aqueous acetonitrile 1:2 Wc/Vs provided the best results for syrup and powder, respectively. We strongly believe that the current study could support the standardization of the metabolomics sample preparation process to enable more efficient LC-MS/MS carob analysis.

Process Optimization of Phytoantioxidant and Photoprotective Compounds from Carob Pods (Ceratonia siliqua L.) Using Ultrasonic Assisted Extraction Method

The current study first describes the extraction of phytoantioxidant polyphenols from Carob byproducts (pods) using maceration and heating-assisted extraction as traditional methods and ultrasonic-assisted extraction (UAE) as an innovative method to determine the most efficient extraction process in terms of four targeted responses: total phenolic content (TPC), antioxidant activities (TAC and DPPH), and photoprotective properties as measured by the sun protection factor (SPF). Second, we used response surface methodology (RSM) with a central composite rotatable design (CCDR) approach to investigate the influence of process variables (extraction time, extraction temperature, and solvent concentration) on UAE, which was found to be the most effective extraction technique in our study. Carob byproduct extracts had a TPC ranging from 6.21 to 21.92 mg GAE/g dw, a TAC ranging from 22.00 to 49.30 mg AAE/g dw, DPPH scavenging activity ranging from 56.35 to 90.50%, and SPF values ranging from 8.62 to 22.37. The optimal UAE conditions for maximum TPC, TAC, DPPH, and SPF responses were determined to be 38.90% ethanol, 53.90 °C, and 50.92 min. Using Carob as a source for sustainable and bioactive products in conjunction with optimized UAE is a promising contribution to the cosmetic industry that will help to strengthen the concept of environmentally-friendly "green chemistry". Given that Carob pulp or seeds are considered food byproducts, the research presented here encourages the use of these agri-food waste materials in cosmetics.

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.

The Effect of Vibratory Grinding Time on Moisture Sorption, Particle Size Distribution, and Phenolic Bioaccessibility of Carob Powder

Carob pod powder, an excellent source of health-promoting substances, has found its use in a wide range of food products. Grinding conditions affect the physical and chemical properties of the powder, but their influence on the bioaccessibility of phenolic compounds in carob pod powder has not yet been determined. The carob pods were ground for 30-180 s in a vibratory grinder. The median values (D₅₀) of particle size decreased after 60 s of grinding (87.9 μm), then increased to 135.1 μm. Lightness showed a negative correlation with D₅₀ and a_w, while the values of redness and yellowness decreased with the reduction in particle size and water activity. The smaller the value of D₅₀, the higher the equilibrium moisture content of carob powder. Phenolic acids (vanillic, ferulic, cinnamic) and flavonoids (luteolin, naringenin, apigenin) were found in all samples of carob powder. The grinding time influenced their content in carob powder, with maximum values at 180 s. Similar observations were made when assessing antioxidant capacity. The in vitro digestion process only improved the bioaccessibility of catechin content in all samples. However, the bioaccessibility of the phenolic compounds and the total phenolic and flavonoid contents decreased with the increase in grinding time. Our findings revealed that the grinding of carob pods for 180 s improved the extractability of phenolics; however, their bioaccessibility was reduced. It is sufficient to ground the carob pod for 30 s, ensuring good availability of nutraceuticals and lower energy cost for grinding.