Dietary alkylresorcinols and cancer prevention: a systematic review

Dietary Intake of (Poly)phenols and Risk of All-Cause and Cause-Specific Mortality in the Mexican Teachers' Cohort Study

BACKGROUND

Observational studies have reported that total (poly)phenol intake is associated with a reduction in all-cause and cardiovascular mortality, but mainly from high-income countries, where (poly)phenol intake may differ from that of low- and middle-income countries.

OBJECTIVES

Our objective was to evaluate the association between the intake of total, all classes, and subclasses of (poly)phenols and risk of all-cause and cause-specific mortality in a Mexican cohort.

METHODS

We used data from the Mexican Teachers' Cohort, which included 95,313 adult females. After a median follow-up of 11.2 y, 1725 deaths were reported, including 674 from cancer and 282 from cardiovascular diseases. (Poly)phenol intake was estimated using a validated food frequency questionnaire and the Phenol-Explorer database. Multivariable Cox models were applied to estimate the association between (poly)phenol intake and all-cause mortality and competitive risk models for cause-specific mortality.

RESULTS

Comparing extreme quartiles, total (poly)phenol intake was associated with lower risk of all-cause [hazard ratio (HR)Q4vs.Q1: 0.88; 95% CI: 0.76, 0.99; P-trend = 0.01] and cancer mortality (HRQ4vs.Q1: 0.81; 95% CI: 0.64, 0.99; P-trend = 0.02). Among (poly)phenol classes, phenolic acids, particularly hydroxycinnamic acids from coffee, showed an inverse association with all-cause (HRQ4vs.Q1: 0.79; 95% CI: 0.69, 0.91; P-trend = 0.002) and cancer mortality (HRQ4vs.Q1: 0.75; 95% CI: 0.61, 0.94; P-trend = 0.03). No associations were observed with flavonoids or with cardiovascular mortality.

CONCLUSION

Our study suggests that high (poly)phenol intake, primarily consisting of phenolic acids such as hydroxycinnamic acids, may have a protective effect on overall and cancer mortality. Null associations for flavonoid intake might be due to the potential underestimation of their intake in this population.

Supplementation of a High-Fat Diet with Pentadecylresorcinol Increases the Representation of Akkermansia muciniphila in the Mouse Small and Large Intestines and May Protect against Complications Caused by Imbalanced Nutrition

Imbalanced nutrition, such as a high-fat/high-carbohydrate diet, is associated with negative effects on human health. The composition and metabolic activity of the human gut microbiota are closely related to the type of diet and have been shown to change significantly in response to changes in food content and food supplement administration. Alkylresorcinols (ARs) are lipophilic molecules that have been found to improve lipid metabolism and glycemic control and decrease systemic inflammation. Furthermore, alkylresorcinol intake is associated with changes in intestinal microbiota metabolic activity. However, the exact mechanism through which alkylresorcinols modulate microbiota activity and host metabolism has not been determined. In this study, alterations in the small intestinal microbiota (SIM) and the large intestinal microbiota (LIM) were investigated in mice fed a high-fat diet with or without pentadecylresorcinol (C15) supplementation. High-throughput sequencing was applied for jejunal and colonic microbiota analysis. The results revealed that C15 supplementation in combination with a high-fat diet could decrease blood glucose levels. High-throughput sequencing analysis indicated that C15 intake significantly increased (p < 0.0001) the abundance of the probiotic bacteria Akkermansia muciniphila and Bifidobacterium pseudolongum in both the small and large intestines and increased the alpha diversity of LIM (p < 0.05), but not SIM. The preliminary results suggested that one of the mechanisms of the protective effects of alkylresorcinol on a high-fat diet is the modulation of the content of SIM and LIM and metabolic activity to increase the probiotic bacteria that alleviate unhealthy metabolic changes in the host.

Intake of polyphenols from cereal foods and colorectal cancer risk in the Melbourne Collaborative Cohort Study

BACKGROUND

Cereal-derived polyphenols have demonstrated protective mechanisms in colorectal cancer (CRC) models; however, confirmation in human studies is lacking. Therefore, this study examined the association between cereal polyphenol intakes and CRC risk in the Melbourne Collaborative Cohort Study (MCCS), a prospective cohort study in Melbourne, Australia that recruited participants between 1990 and 1994 to investigate diet-disease relationships.

METHODS

Using food frequency questionnaire diet data matched to polyphenol data, dietary intakes of alkylresorcinols, phenolic acids, lignans, and total polyphenols from cereals were estimated. Hazard ratios (HRs) and 95% confidence intervals for CRC risk were estimated for quintiles of intake with the lowest quintile as the comparison category, using multivariable adjusted Cox proportional hazards models with age as the time axis adjusted for sex, socio-economic status, alcohol consumption, fibre intake, country of birth, total energy intake, physical activity and smoking status.

RESULTS

From 35,245 eligible adults, mean (SD) age 54.7 (8.6) years, mostly female (61%) and Australian-born (69%), there were 1394 incident cases of CRC (946 colon cancers and 448 rectal cancers). Results for total cereal polyphenol intake showed reduced HRs in Q2 (HR: 0.80; 95% CI, 0.68-0.95) and Q4 (HR: 0.75; 95% CI, 0.62-0.90), and similar for phenolic acids. Alkylresorcinol intake showed reduced HR in Q3 (HR: 0.80; 95% CI, 0.67-0.95) and Q4 (HR: 0.79; 95% CI, 0.66-0.95).

CONCLUSIONS

Overall, the present study showed little evidence of association between intakes of cereal polyphenols and CRC risk. Future investigations may be useful to understand associations between cereal-derived polyphenols and additional cancers in different populations.

Profiling and Isolation of Ten Rare Branched-Chain Alkylresorcinols in Quinoa

Alkylresorcinols (∑ARs) are bioactive lipid compounds predominantly found in cereals. These amphiphilic compounds exist in a high structural diversity and can be divided into two main groups, i.e., 5-alkylresorcinols (ARs) and 2-methyl-5-alkylresorcinols (mARs). The pseudocereal quinoa has a very unique AR profile, consisting not only of straight-chain alkyl chains but also iso- and anteiso-branched isomers. Here, we describe a method for the isolation of such methyl-branched ARs and mARs from quinoa. The enrichment of the ∑AR fraction from the lipid extracts by centrifugal partition chromatography (CPC) was followed by ∑AR profiling using countercurrent chromatography (CCC) and GC/MS analysis of CCC fractions. A total of 112 ∑ARs could be detected, 63 of which had not been previously described in quinoa. Due to this high number of ∑ARs, the direct isolation of individual ARs was not possible using conventional CCC. Instead, the more powerful heart-cut mode was applied to enrich the target compounds. A final purification step-the separation of CCC-co-eluting mARs from ARs -was performed via silver ion chromatography. Altogether, ten rare branched-chain ∑ARs (five iso-branched mARs and five anteiso-branched ARs, including mAR19:0-i and AR20:0-a) were isolated with purities up to 98% in the double-digit mg range.

Estimated dietary intake of polyphenols from cereal foods and associated lifestyle and demographic factors in the Melbourne Collaborative Cohort Study

Cereal foods are consumed globally and are important sources of polyphenols with potential health benefits, yet dietary intakes are unclear. We aimed to calculate the dietary intakes of polyphenols from cereal foods in the Melbourne Collaborative Cohort Study (MCCS), and describe intakes by demographic and lifestyle factors. We estimated intakes of alkylresorcinols, lignans and phenolic acids in n = 39,892 eligible MCCS participants, using baseline dietary data (1990-1994) from a 121-item FFQ containing 17 cereal foods, matched to a polyphenol database developed from published literature and Phenol-Explorer Database. Intakes were estimated within groups according to lifestyle and demographic factors. The median (25th-75th percentile) intake of total polyphenols from cereal foods was 86.9 mg/day (51.4-155.8). The most consumed compounds were phenolic acids, with a median intake of 67.1 mg (39.5-118.8), followed by alkylresorcinols of 19.7 mg (10.8-34.6). Lignans made the smallest contribution of 0.50 mg (0.13-0.87). Higher polyphenol intakes were associated with higher relative socio-economic advantage and prudent lifestyles, including lower body mass index (BMI), non-smoking and higher physical activity scores. The findings based on polyphenol data specifically matched to the FFQ provide new information on intakes of cereal polyphenols, and how they might vary according to lifestyle and demographic factors.

Alkyl aromatic derivatives from the endophytic fungus Cytospora rhizophorae

Two new alkylresorcinols named herein 5'-methoxy-integracins A-B (1-2), two new monomeric alkyl aromatic derivatives 3-(7-hydroxyheptyl)-5-methoxyphenol (5) and 7-(3,5-dihydroxyphenyl) heptyl acetate (6), along with four known compounds including integracins A-B (3-4), 2,4-dihydroxy-6-(8-hydroxyoctyl) benzene (7), and cytosporone B (8) were isolated from the endophytic fungus Cytospora rhizophorae A761. The structures of the four new compounds were elucidated by NMR, HRESIMS data, and electronic circular dichroism (ECD) calculations, whereas the compounds 1 and 2 were disclosed as a class of the natural rare-occurring dimeric alkylresorcinol derivatives. Moreover, the bioassays of the new compounds clarified that compound 1 was a potent inhibitor for the α-glucosidase, and compound 2 showed relatively good activity against the tumor cell lines. It is worth mentioning that the known compound integracin B (4) was first reported to display significant antibacterial activity against Staphylococcus aureus and methicillin-resistant Staphylococcus aureus (MRSA) with MIC values of 6.25 μg ml^-1.

Analysis of the multi-physiological and functional mechanism of wheat alkylresorcinols based on reverse molecular docking and network pharmacology

Alkylresorcinols (ARs) are phenolic lipids present in the bran part of whole grain wheat and rye, which possess antioxidant, anti-inflammatory, anti-cancer and anti-tumor properties. The physiological activities of ARs have been proven to be diverse; however, the specific molecular mechanisms are still unclear. In this study, reverse virtual screening and network pharmacology were used to explore the potential molecular mechanisms of the physiological function of ARs and their endogenous metabolites. The Metascape database was used for GO enrichment and KEGG pathway analysis. Furthermore, molecular docking was used to investigate the interactions between active compounds and potential targets. The results showed that the bioavailability of most ARs and their endogenous metabolites was 0.55 and 0.56, while the bioavailability of certain endogenous metabolites was only 0.11. Multiplex analysis was used to screen 73 important targets and 4 core targets (namely, HSP90AA1, EP300, HSP90AB1 and ERBB2) out of the 163 initial targets. The important targets involved in the key KEGG pathway were pathways in cancer (hsa05200), lipid and atherosclerosis (hsa05417), Th17 cell differentiation (hsa04659), chemical carcinogenesis-receptor activation (hsa05207), and prostate cancer (hsa05215). The compounds involved in the core targets were AR-C21, AR-C19, AR-C17, 3,5-DHPHTA-S, 3,5-DHPHTA-G, 3,5-DHPPTA, 3,5-DHPPTA-S, 3,5-DHPPTA-G, 3,5-DHPPTA-Gly and 3,5-DHPPA-G. The interaction force between them was mainly related to hydrogen bonds and van der Waals. Overall, the physiological activities of ARs are not only related to their multiple targets, but may also be related to the synergistic effect of their endogenous metabolites.

Effects of 4-hexylresorcinol administration on the submandibular glands in a growing rat model

Background

4-Hexylresorcinol (4HR) is a food additive and class I histone deacetylase inhibitor. In this study, we examined the effects of 4HR administration on the submandibular gland in a growing rat model.

Methods

Four-week-old rats were used in this study. The experimental group (nine males and eight females) received 12.8 mg/kg of 4HR weekly for 12 weeks. Ten rats (five males and five females) were used as controls. The submandibular glands of rats were collected 12 weeks after the first administration of 4HR. The weight of the glands was measured. Histological analysis, immunoprecipitation-high-performance liquid chromatography (IP-HPLC), and western blotting were performed.

Results

The weights of the rat submandibular glands were higher in the experimental groups than in the control group, especially in male rats (P < 0.05). The vascular endothelial growth factor (VEGF) and testosterone in the submandibular glands were more highly expressed in 4HR-treated male rats than in untreated rats, as detected by both western blotting and immunohistochemistry. The IP-HPLC results demonstrated that the expression levels of Ki67, epidermal growth factor, and testosterone in the submandibular glands were higher in 4HR-treated male rats than in untreated rats.

Conclusions

This study demonstrated that the systemic administration of 4HR increased the weight of submandibular glands in male rats. In addition, the testosterone and VEGF expression levels in the submandibular glands increased owing to 4HR administration.

A comprehensive review of wheat phytochemicals: From farm to fork and beyond

The health benefits of whole wheat consumption can be partially attributed to wheat's phytochemicals, including phenolic acids, flavonoids, alkylresorcinols, carotenoids, phytosterols, tocopherols, and tocotrienols. It is of increasing interest to produce whole wheat products that are rich in bioactive phytochemicals. This review provides the fundamentals of the chemistry, extraction, and occurrence of wheat phytochemicals and includes critical discussion of several long-lasting issues: (1) the commonly used nomenclature on distribution of wheat phenolic acids, namely, soluble-free, soluble-conjugated, and insoluble-bound phenolic acids; (2) different extraction protocols for wheat phytochemicals; and (3) the chemistry and application of in vitro antioxidant assays. This review further discusses recent advances on the effects of genotypes, environments, field management, and processing techniques including ultrafine grinding, germination, fermentation, enzymatic treatments, thermal treatments, and food processing. These results need to be interpreted with care due to varied sample preparation protocols and limitations of in vitro assays. The bioaccessibility, bioavailability, metabolism, and potential health benefits of wheat phytochemicals are also reviewed. This comprehensive and critical review will benefit scientific researchers in the field of bioactive compounds of cereal grains and also those in the cereal food industry to produce high-quality functional foods.

General Health Benefits and Pharmacological Activities of Triticum aestivum L

Common wheat (Triticum aestivum), one of the world's most consumed cereal grains, is known for its uses in baking and cooking in addition to its medicinal uses. As this plant's medical benefits are enormous and scattered, this narrative review was aimed at describing the pharmacological activities, phytochemistry, and the nutritional values of Triticum aestivum. It is a good source of dietary fiber, resistant starch, phenolic acids, alkylresorcinols, lignans, and diverse antioxidant compounds such as carotenoids, tocopherols and tocotrienols. These constituents provide Triticum aestivum with a wide range of pharmacological properties, including anticancer, antimicrobial, antidiabetic, hypolipemic, antioxidant, laxative, and moisturizing effects. This review summarized the established benefits of wheat in human health, the mode of action, and different clinical, in vitro and in vivo studies for different varieties and cultivars. This review also gives an insight for future research into the better use of this plant as a functional food. More clinical trials, in vivo and in vitro studies are warranted to broaden the knowledge about the effect of Triticum aestivum on nutrition-related diseases prevention, and physical and mental well-being sustenance.

An Overview of Alkylresorcinols Biological Properties and Effects

The investigation of alkylresorcinols has drawn an increasing interest recently. Alkylresorcinols (ARs) are natural chemical compounds synthesized by bacteria, fungi, sponges, and higher plants, possessing a lipophilic polyphenol structures and a myriad of biological properties. Human takes ARs as a component of a whole grain diet (from whole grain rye, wheat, and barley products), and thus, alkylresorcinols are frequently used as whole grain intake markers. Besides, ARs are considered as promising bioregulators of metabolic and immune processes, as well as adjuvant therapeutic agents for antimicrobial and anticancer treatment. In this review, we attempted to systematize the accumulated information concerning ARs origin, metabolism, biological properties, and their effect on human health.

Starch inclusion complex for the encapsulation and controlled release of bioactive guest compounds

The linear component of starch, especially amylose, is capable of forming inclusion complex (IC) with various small molecules. It could significantly modify the structure and properties of starch, and it could bring beneficial effects when bioactive compounds can be encapsulated. This review discusses the formation and characterization of the starch-guest IC and focuses on the recent developments in the use of starch ICs for the encapsulation and controlled release of bioactive guest compounds. A great number of guest compounds, such as lipids, aroma compounds, pharmaceuticals, and phytochemicals, were studied for their ability to be complexed with starch and/or amylose and some of the formed ICs were evaluated for the chemical stability improvement and the guest release regulation. Starch-guest ICs has a great potential to be a delivery system, as most existing studies demonstrated the enhancement on guest retention and the possibility of controlled release.

Isolation of saturated alkylresorcinols from rye grains by countercurrent chromatography

Alkylresorcinols (5-alkyl-1,3-dihydroxybenzenes) are amphiphilic phenolic lipid compounds that are abundant in cereals with highest contents in rye. Alkylresorcinols are suspected to show a wide range of favourable biological activities. For such and further testing, highly pure alkylresorcinol standards are required. Especially, purities >> 98% were partly difficult to obtain in the past. Here, we aimed to isolate the most abundant (saturated) alkylresorcinols from rye using countercurrent chromatography. To achieve very high purity, alkylresorcinol-containing extract (∼7.14 g) of rye grains (cold extracts with cyclohexane/ethyl acetate (46/54, w/w)) were preparatively transesterified followed by a preparative hydrogenation. Countercurrent chromatography separation of ∼1 g hydrogenated and transesterified rye grain extract using the solvent system n-hexane-ethyl acetate-methanol-water (9:1:9:1, v/v/v/v) yielded 51.8 mg AR17:0, 77.4 mg AR19:0, 57.2 mg AR21:0, 28.8 mg AR23:0 and 11.5 mg AR25:0 with purities >99% in either case. The isolated alkylresorcinol homologues can be used for subsequent bioassays.

Effect of alkyl chain length on the antioxidant activity of alkylresorcinol homologues in bulk oils and oil-in-water emulsions

The antioxidant cut-off theory details the importance of fine-tuning antioxidant hydrophobicity to optimize antioxidant effectiveness for a given food system; however, previous research has utilized synthetic antioxidant homologues which fail to align with the food industry's demand for natural ingredients. Alkylresorcinols represent a natural homologous series of phenolipid antioxidants. The antioxidant activities of individual alkylresorcinol homologues were investigated in bulk oils and oil-in-water emulsions. In oils, antioxidant activity decreased as alkyl chain length increased and there was no effect on rate of loss. In emulsions, optimum antioxidant activity was observed at intermediate alkyl chain length (C21:0) and longer homologues were lost more rapidly. Radical scavenging capacity decreased as alkyl chain length increased but alkylresorcinols were unable to chelate iron. This suggests that intrinsic properties (e.g. radical scavenging capacity) are responsible for the antioxidant activity of alkylresorcinols in oils while physicochemical phenomena (e.g. partitioning) drive antioxidant activity of alkylresorcinols in emulsions.

An Overview of the Medicinally Important Plant Type III PKS Derived Polyketides

Plants produce interesting secondary metabolites that are a valuable source of both medicines for human use, along with significant advantages for the manufacturer species. The active compounds which lead to these instrumental effects are generally secondary metabolites produced during various plant growth phases, which provide the host survival advantages while affecting human health inadvertently. Different chemical classes of secondary metabolites are biosynthesized by the plant type III polyketide synthases (PKSs). They are simple homodimeric proteins with the unique mechanistic potential to produce a broad array of secondary metabolites by utilizing simpler starter and extender units. These PKS derived products are majorly the precursors of some important secondary metabolite pathways leading to products such as flavonoids, stilbenes, benzalacetones, chromones, acridones, xanthones, cannabinoids, aliphatic waxes, alkaloids, anthrones, and pyrones. These secondary metabolites have various pharmaceutical, medicinal and industrial applications which make biosynthesizing type III PKSs an important tool for bioengineering purposes. Because of their structural simplicity and ease of manipulation, these enzymes have garnered interest in recent years due to their application in the generation of unnatural natural polyketides and modified products in the search for newer drugs for a variety of health problems. The following review covers the biosynthesis of a variety of type III PKS-derived secondary metabolites, their biological relevance, the associated enzymes, and recent research.

New Alkenylresorcinols with Cytotoxic and Antimicrobial Activities from the Leaves of Embelia schimperi

A phytochemical study of the methanol extract of the leaves of Embelia schimperi resulted in the isolation of three new alkenylresorcinols, 1:  - 3: , together with the known analogs 4:  - 7: . Their structures were established by a combination of spectroscopic techniques. Compounds 1:  - 7: exhibited moderate cytotoxic activity against human cervical cancer cells HeLa-S3 and more pronounced antimicrobial properties towards bacteria and filamentous fungi. The present study falls into an ongoing research project on the characterization of bioactive phenolic lipids from plants of the family Primulaceae.

Natural Function and Structural Modification of Climacostol, a Ciliate Secondary Metabolite

The review highlights the main results of two decades of research on climacostol (5-[(2Z)-non-2-en-1-yl]benzene-1,3-diol), the resorcinolic lipid produced and used by the ciliated protozoan Climacostomum virens for chemical defense against a wide range of predators, and to assist its carnivorous feeding. After the first studies on the physiological function of climacostol, the compound and some analogues were chemically synthesized, thus allowing us to explore both its effect on different prokaryotic and eukaryotic biological systems, and the role of its relevant structural traits. In particular, the results obtained in the last 10 years indicate climacostol is an effective antimicrobial and anticancer agent, bringing new clues to the attempt to design and synthesize additional novel analogues that can increase or optimize its pharmacological properties.

Solid state fermentation by Fomitopsis pinicola improves physicochemical and functional properties of wheat bran and the bran-containing products

Wheat bran was solid state fermented by Fomitopsis pinicola. The results showed that the processing properties were increased by fermentation and the content of total phenol and alkylresorcinols was 5.91 and 1.55 times of the unfermented bran respectively by the 6th day. The total antioxidant capacity was 5.73 times of the unfermented sample by the 4th day. Electronic nose analysis showed that the fermented wheat bran had a special flavor. GC-MS analysis found that 4-ethyl-2-methoxy-phenol was the main flavor substance, which was sharply increased during the fermentation. Furthermore, the textural properties of the dough and bread containing fermented bran were significantly improved. The content of phytic acid in the bread was significantly decreased, while the protein, total phenol and alkylresorcinols contents were significantly increased. Results suggest that solid state fermentation by Fomitopsis pinicola is a promising way to improve wheat bran to a nutritious and flavorful cereal food ingredient.

Effect of Moringa oleifera L. Leaf Powder Addition on the Phenolic Bioaccessibility and on In Vitro Starch Digestibility of Durum Wheat Fresh Pasta

Fresh pasta was formulated by replacing wheat semolina with 0, 5, 10, and 15 g/100 g (w/w) of Moringa oleifera L. leaf powder (MOLP). The samples (i.e., M0, M5, M10, and M15 as a function of the substitution level) were cooked by boiling. The changes in the phenolic bioaccessibility and the in vitro starch digestibility were considered. On the cooked-to-optimum samples, by means of ultra-high-performance liquid chromatography-quadrupole time-of-flight (UHPLC-QTOF) mass spectrometry, 152 polyphenols were putatively annotated with the greatest content recorded for M15 pasta, being 2.19 mg/g dry matter (p < 0.05). Multivariate statistics showed that stigmastanol ferulate (VIP score = 1.22) followed by isomeric forms of kaempferol (VIP scores = 1.19) and other phenolic acids (i.e., schottenol/sitosterol ferulate and 24-methylcholestanol ferulate) were the most affected compounds through the in vitro static digestion process. The inclusion of different levels of MOLP in the recipe increased the slowly digestible starch fractions and decreased the rapidly digestible starch fractions and the starch hydrolysis index of the cooked-to-optimum samples. The present results showed that MOLP could be considered a promising ingredient in fresh pasta formulation.

Bioactive Compounds of a Wheat Bran Oily Extract Obtained with Supercritical Carbon Dioxide

A wheat bran oily extract obtained with supercritical carbon dioxide at 25.0 ± 0.1 MPa and 40 ± 2 °C has been analyzed in order to determine some valuable bioactive compounds as alkylresorcinols, α-linolenic acid, steryl ferulates, tocopherols and phenolic compounds, which levels were around 47, 37, 18, 7 and 0.025 mg/g oily extract, respectively. To our knowledge, this is the first time that the presence of steryl ferulates has been observed in a supercritical fluid extract of wheat bran and that γ-tocopherol has been described in wheat bran oily extracts. Other common quality parameters, directly correlated with oxidative degradation, were also evaluated. Acidity values around 15% oleic acid were detected, while low levels of hydroperoxides (around 2.4 meq O₂/kg) and very low levels of hexanal (0.21 ppb) were found. Composition of the wheat bran oily extract was stable during 155 days of storage at 21 °C and darkness, and only a slight decrease in alkylresorcinols and tocopherols contents (13% and 20%, respectively) was observed. These results indicated an attractive potential of the obtained oily extract for industrial applications as food ingredients, nutraceuticals, and others.

Study on chemopreventive effects of raw and roasted β-glucan-rich waxy winter barley using an in vitro human colon digestion model

Fermentation supernatants of barley flakes exhibit chemopreventive effects in LT97 colon adenoma cells without impact of roasting.

Stone Milling versus Roller Milling in Soft Wheat: Influence on Products Composition

Wholegrain wheat flours are in great demand from consumers worldwide because they are considered healthier then refined flours. They can be obtained by either stone milling, which is experiencing a revival in Europe, or roller milling. In order to study compositional differences due to the milling technology and to explore the possibility of a better qualification of wholegrain flours by means of nutritionally oriented quality parameters, eight mixes of soft wheat grains were stone milled and roller milled and the milling products were analyzed for their protein, ash, lipids, total dietary fibre, total polyphenols and alkylresorcinols content. A wholegrain flour milled with a laboratory disk mill was used as a comparison and a set of seven wholegrain flours purchased on themarket were also analyzed and compared. The particle size distribution of stone milled and recombined roller milled flour was also studied. Considering the above mentioned parameters, we found that there is no compositional difference between a stone milled or a roller milled flour if, in this latter one, the milling streams are all recombined, but the particle size distribution was different. This might have an impact on the technological quality of flours and on the bioavailability of components.

Wheat Bran for Colon Cancer Prevention: The Synergy between Phytochemical Alkylresorcinol C21 and Intestinal Microbial Metabolite Butyrate

There is convincing evidence that consuming whole grains (WGs) may decrease the risk of colorectal cancer (CRC). Wheat bran (WB) is a rich source of dietary fiber and phytochemicals with health-promoting properties. However, the active components especially the interaction between different components in WG wheat have not been fully explored. Here, we investigated whether one of the major WB phytochemicals, alkylresorcinol (AR) C21, and the major active intestinal microbial metabolite of fiber, butyrate, could synergistically suppress human colon cancer cells. Our results demonstrated for the first time that the combination of C21 and butyrate synergistically inhibited the growth of human colon cancer cells and induced apoptosis. Further mechanistic studies demonstrated that the cotreatment of C21 and butyrate induced significant up-regulations in cleaved Poly(ADP-ribose) polymerase (PARP), cleaved caspase 3, p53 upregulated modulator of apoptosis (PUMA), cytochrome C, lipid-conjugated membrane-bound form of microtubule-associated protein 1A/1B-light chain 3 (LC3-II), and C/EBP homologous protein (CHOP) expressions, indicating the synergistic anticancer effects of C21 and butyrate were associated with induction of apoptosis, autophagy, and ER stress pathways. Notably, the C21 concentrations in the large intestinal tract of mice treated with human relevant doses of C21, were from 0.86 to 1.78 μmol/g, suggesting the C21 doses used in vitro may be achievable after daily WG wheat intake. These results provide novel insights into the dietary prevention of CRC regarding the potential interaction of bioactive WG wheat phytochemicals and the microbial metabolites of fiber.

Whole Grain Consumption for the Prevention and Treatment of Breast Cancer

Breast cancer is one of the most common and malignant cancers among females worldwide. Several epidemiological studies have indicated the inverse correlation between the intake of whole grains and the incidence of breast cancer. Whole grains are the most fundamental and important food source of bioactive phytochemicals, which have well-defined roles in the management of each stage of breast carcinogenesis. To better understand the value of whole grains in future prevention and treatment of breast cancer, the effects and possible mechanisms of six different whole grain cereals, which are the most commonly consumed throughout the world, are introduced in the current review. Moreover, the bioactive compounds extracted from whole grains are adequately formulated and the underlying mechanism of action is illustrated. In addition, the present limitations and future perspective of whole grain consumption for breast cancer are also concluded. The objective of this review is to promote the development of nutraceutical and functional food from whole grains and its application for reducing the risk of breast cancer.

Transformation of polyphenols found in pigmented gluten-free flours during in vitro large intestinal fermentation

In this work, 18 gluten-free flours (prepared from cereals, pseudocereals and legumes), differing in pigmentation, were screened for their phenolic profiles, cooked and, then, subjected to digestion and large intestinal fermentation in vitro. A combined targeted/untargeted metabolomic approach was used to elucidate the microbial biotransformation processes of polyphenols following digestion. This preliminary work demonstrated an increase in 3,5-dihydroxybenzoic acid (on average from 0.67 up to 1.30 μmol/g dry matter) throughout large intestinal fermentation of pseudocereals (esp. quinoa), due to their high alkylresorcinol contents. Isoflavones were converted into equol- or O-desmethylangolensin- derivatives, whereas anthocyanins were degraded into lower-molecular-weight phenolics (i.e., protocatechuic aldehyde and 4-hydroxybenzoic acid, with the latter exhibiting the highest increase over time). A decreasing trend was observed for antioxidant activities (i.e., FRAP and ORAC values) moving from digested to faecal fermented samples. These findings highlight that gluten-free flours are able to deliver bioaccessible polyphenols to the colon.

High-Performance Thin-Layer Chromatography Hyphenated with Microchemical and Biochemical Derivatizations in Bioactivity Profiling of Marine Species

Marine organisms produce an array of biologically active natural products, many of which have unique structures that have not been found in terrestrial organisms. Hence, marine algae provide a unique source of bioactive compounds. The present study investigated 19 marine algae and one seagrass collected from Torquay beach, Victoria, Australia. High-performance thin-layer chromatography (HPTLC) hyphenated with microchemical (DPPH•, p-anisaldehyde, and Fast Blue B) and biochemical (α-amylase and acetylcholine esterase (AChE) enzymatic) derivatizations was used to evaluate antioxidant activity, presence of phytosterols and phenolic lipids, α-amylase and AChE inhibitory activities of extract components. Significant α-amylase and AChE inhibitory activities were observed in samples 2, 6, 8 and 10. Antioxidant activities in the samples were found to be correlated to phytosterol content (R² = 0.78), but was not found to be related to either α-amylase or AChE inhibitory activities. α-Amylase inhibitory activities were correlated to AChE inhibition (R² = 0.77) and attributed to the phytosterol content, based on the similar peak position in the chromatograms with the β-sitosterol chromatogram. Samples 1, 8, and especially sample 20, were found to contain phenolic lipids (alkyl resorcinol derivatives) with significant antioxidant activities. The results suggest that these marine species have a significant number of bioactive compounds that warrant further investigation.

Cardanols detected in non-polar propolis extracts from Scaptotrigona aff. postica (Hymenoptera, Apidae, Meliponini)

Abstract The propolis produced by stingless bees of the tribe Meliponini is a viscous product that contains the resin collected from buds, leaves and plant exudates, mixed with salivary secretions, wax and soil. The species Scaptotrigona aff. postica (Latreille, 1807), (Hymenoptera, Apidae, Meliponinae) popularly known as “tubi” in Maranhão State, Brazil, does not mix soil to produce its propolis. The propolis from S. postica harvested in Barra do Corda, Maranhão State, is popularly used in the treatment of wounds and respiratory illnesses. The hydroalcoholic extract of this propolis, rich in flavone-6,8-di-C-glycosides (vicenin-2 and schaftoside), pyrrolizidine alkaloids derived from retronecine, catechin and caffeoylquinic acid derivatives exhibited antiviral activity against the herpes simplex and rubella viruses. The aim of this study was to increase knowledge about the chemical composition of the S. postica propolis by analyzing non-polar extracts obtained using hexane and chloroform as the solvents, by GC-EI-MS. A total of 15 constituents were identified comparing their respective mass spectral data with those available in the NIST data bases and those reported in the literature. The main constituents detected were the phenolic lipids, known as cardanols, 3-(4,7-heptadecadienyl) phenol (5), 3-(10-heptadecenyl) phenol (7), 3-heptadecylphenol (9) and 3-pentadecyl phenol or hydrocardanol (13), which predominated in the hexane extract, while the predominant constituents in the chloroform extract were 3-pentadecyl phenol or hydrocardanol (13) and 3-(8-pentadecenyl) phenol (12). The antioxidant, antitumoral, antifeedant, cytotoxic, anticarcinogenic, antiproliferative, antimicrobial, antileishmanial and larvicidal activities of the cardanols have been demonstrated in many studies.