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Erick Damian Castañeda-Reyes,1,2 Maria de Jesús Perea-Flores,3 Gloria Davila-Ortiz,1 Youngsoo Lee,2 Elvira Gonzalez de Mejia2 1Departamento de Ingeniería Bioquímica, Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional (IPN), Unidad Profesional Adolfo Lopez Mateos, Ciudad De México, 07738, México; 2Department of Food Science and Human Nutrition, University of Illinois at Urbana–Champaign, Champaign, IL, USA; 3Centro de Nanociencias y Micro y Nanotecnologías, Instituto Politécnico Nacional (IPN), Unidad Profesional Adolfo López Mateos, Ciudad De México 07738, MéxicoCorrespondence: Elvira Gonzalez de MejiaDepartment of Food Science and Human Nutrition, University of Illinois at Urbana–Champaign, 228 ERML, 1201 West Gregory Dr, Urbana, IL 61801, USATel +1 217 244-3196Email edemejia@illinois.eduAbstract: The skin is the largest organ in the human body, providing a barrier to the external environment. It is composed of three layers: epidermis, dermis and hypodermis. The most external epidermis is exposed to stress factors that may lead to skin conditions such as photo-aging and skin cancer. Some treatments for skin disease utilize the incorporation of drugs or bioactive compounds into nanocarriers known as liposomes. Liposomes are membranes whose sizes range from nano to micrometers and are composed mostly of phospholipids and cholesterol, forming similar structures to cell membranes. Thus, skin treatments with liposomes have lower toxicity in comparison to traditional treatment routes such as parenteral and oral. Furthermore, addition of edge activators to the liposomes decreases the rigidity of the bilayer structure making it deformable, thereby improving skin permeability. Liposomes are composed of an aqueous core and a lipidic bilayer, which confers their amphiphilic property. Thus, they can carry hydrophobic and hydrophilic compounds, even simultaneously. Current applications of these nanocarriers are mainly in the cosmetic and pharmaceutic industries. Nevertheless, new research has revealed promising results regarding the effectiveness of liposomes for transporting bioactive compounds through the skin. Liposomes have been well studied; however, additional research is needed on the efficacy of liposomes loaded with bioactive peptides for skin delivery. The objective of this review is to provide an up-to-date description of existing techniques for the development of liposomes and their use as transporters of bioactive compounds in skin conditions such as melanoma and skin inflammation. Furthermore, to gain an understanding of the behavior of liposomes during the process of skin delivery of bioactive compounds into skin cells.Keywords: edge activators, encapsulation, inflammation, melanoma, nanotransporters, skin delivery, ultadeformable liposomes

Common bean has the potential to improve gut microbiota function due to its chemical composition and content of dietary fiber. This study evaluated the effect of cooked common bean (CCB) flour and its protein hydrolysate as part of a high-fat diet (HFD) added with 6-propyl-2-thiouracil (10 mg/kg/d), an inhibitor of thyroid hormone synthesis, on gut health of BALB/c mice. Forty-eight adult mice were divided into four groups: normal control; HFD; HFD plus CCB flour (346.6 g/kg of diet) (HFBF group) and HFD plus CCB protein hydrolysate (700 mg/Kg/d) (HFPH group). HFBF, but not HFPH, increased cecum weight, and the moisture, and lipids in the excreted feces, compared to control groups. Sequencing of the 16S rRNA gene of the cecal microbiota indicated changes in the beta-diversity between the HFBF and HFPH groups, compared to the normal control. The abundance of Bacteroidetes increased and the Firmicutes/Bacteroidetes ratio decreased in the HFBF compared to control groups. However, HFPH was not able to prevent the damage caused by a HFD to the gut bacterial communities. The OTUs enriched by HFBF were mainly assigned to members of the Muribaculaceae family, which shows potential to improve gut health. The intake of CCB flour improved intestinal health and modulated the composition and function of the cecal microbiota, attenuating the effects of the HFD, added wit 6-propyl-2-thiouracil, when fed to BALB/c mice., (Copyright © 2022 Elsevier Inc. All rights reserved.)

Background and Aims: Common beans (Phaseolus vulgaris L.) protein hydrolysate is a source of bioactive peptides with known health benefits. The aim of this study was to evaluate the effect of common bean protein hydrolysate on lipid metabolism and endothelial function in male adult BALB/c mice fed an atherogenic diet for nine weeks., Methods and Results: Male adult mice were divided into three experimental groups (n = 12) and fed with normal control diet; atherogenic diet and atherogenic diet added with bean protein hydrolysate (700 mg/kg/day) for nine weeks. Food intake, weight gain, lipid profile, Atherogenic Index of Plasma, inflammation biomarkers and endothelial function were evaluated. APH group presented reduced feed intake, weight gain, lipid profile, tumor necrosis factor-α, angiotensin II (94% and 79%, respectively) and increased endothelial nitric oxide synthase (62%)., Conclusions: Protein hydrolysate showed hypocholesterolemic activity preventing inflammation and dysfunction of vascular endothelium, in addition to decreasing oxidative stress, indicating an adjuvant effect on reducing atherogenic risk., (Copyright © 2019 The Italian Society of Diabetology, the Italian Society for the Study of Atherosclerosis, the Italian Society of Human Nutrition, and the Department of Clinical Medicine and Surgery, Federico II University. Published by Elsevier B.V. All rights reserved.)

Common bean (Phaseolus vulgaris L.) is a source of bioactive peptides, but little is known about its effects on hypercholesterolemia, oxidative stress, and the inflammatory process. Therefore, the aim of this study was to evaluate the effect of whole flour and bean protein hydrolysate of common bean variety Carioca on inflammation and oxidative stress in BALB/c mice. Four experimental groups were included in the study: standard diet (SD), high fat high cholesterol diet (HFC), high fat high cholesterol diet and whole bean flour (HFC-F); and high fat high cholesterol diet and bean protein hydrolysate (HFC-PH). Animals fed with bean protein hydrolysate showed lower weight gain and food intake. Animals fed with whole bean flour showed lower alanine aminotransferase and low-density lipoprotein cholesterol levels than animals fed with bean protein hydrolysate. SOD mRNA was lower in HFC, HFC-F and HFC-PH groups whereas SOD concentration was higher in HFC-F and HFC-PH groups. HSP72 mRNA expression was lower in the HFC-F group in relation to HFC-PH. IL-10 and PPARα mRNA expression was lower in HFC-F and HFC-PH groups in comparison with SD. The whole bean flour and bean protein hydrolysate reduced inflammation and the risk factors for cardiovascular diseases in BALB/c mice., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Anthocyanin-rich powders and aqueous extracts, with high antioxidant activities, were obtained from black bean seed coats and applied to colour a sport beverage. Idaho and Otomi bean coats were extracted in water-citric acid 2% (1/50, w/v), stirring for 4h at 40°C. Anthocyanins from Idaho and Otomi extracts (1.83mg and 1.02mg C3G/g, respectively) were applied to a commercially available sport beverage, with and without 2% β-cyclodextrin (βCD) under light and darkness conditions for 10days, and stored at 4°C and 25°C for 6weeks. At different light and storage conditions, anthocyanin degradation fitted a first-order reaction model. All bean coat anthocyanins combined with βCD showed extended half-life (up to 13months), higher D-values (up to 43months) and fewer differences in colourimetric properties (lightness, chroma and hue angle) under darkness and 4°C conditions. These black bean coat aqueous extracts and powders might represent natural alternatives to synthetic colorants, ecologically extracted, and with a high antioxidant potential., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

The aim was to optimize the production of bioactive peptides from black bean (Phaseolus vulgaris L.) protein isolate and to determine their biological potential using biochemical and in silico approaches. Protein fractions were generated using eight commercially available proteases after 2, 3 and 4 h and 1:20, 1:30 and 1:50 enzyme/substrate (E/S) ratios. The best combination of conditions to generate anti-diabetic peptides was with alcalase for 2 h and E/S of 1:20; with inhibition values for dipeptidyl peptidase IV (DPP-IV, 96.7%), α-amylase (53.4%) and α-glucosidase (66.1%). Generated peptides were characterized using LC-ESI-MS/MS. Molecular docking analysis was performed to predict individual peptide biological potential using DockingServer®. Peptides EGLELLLLLLAG, AKSPLF and FEELN inhibited DPP-IV more efficiently in silico through free energy interactions of -9.8, -9.6 and -9.5 kcal mol(-1), respectively, than the control sitagliptin (-8.67 kcal mol(-1)). The peptide TTGGKGGK (-8.97 kcal mol(-1)) had higher inhibitory potential on α-glucosidase compared to the control acarbose (-8.79 kcal mol(-1)). Peptides AKSPLF (-10.2 kcal mol(-1)) and WEVM (-10.1 kcal mol(-1)) generated a lower free energy interaction with the catalytic site of α-amylase in comparison with acarbose (-9.71 kcal mol(-1)). Bean peptides inhibited the tested enzymes through hydrogen bonds, polar and hydrophobic interactions. The main bindings on the catalytic site were with ASP192, GLU192 and ARG 253 on DPP-IV; TYR151, HIS201 and ILE235 on α-amylase; and ASP34, THR83 and ASN32 on α-glucosidase. For the first time, a systematic evaluation and characterization of the anti-diabetic peptides from black bean protein isolate is presented with the potential for inhibiting important molecular markers related to diabetes.

Common bean (Phaseolus vulgaris L.) is a good source of protein, vitamins, minerals and complex carbohydrates. The objective was to compare protein profile, including anti-nutrient proteins, and potential bioactive peptides of improved common bean cultivars grown in Mexico and Brazil. Bean protein isolates (BPI) were prepared from 15 common bean cultivars and hydrolyzed using pepsin/pancreatin. Thirteen proteins were identified by SDS-PAGE and protein in-gel tryptic-digestion-LC/MS. Protein profile was similar among common bean cultivars with high concentrations of defense-related proteins. Major identified proteins were phaseolin, lectin, protease and α-amylase inhibitors. Lectin (159.2 to 357.9 mg lectin/g BPI), Kunitz trypsin inhibitor (inh) (4.3 to 75.5 mg trypsin inh/g BPI), Bowman-Birk inhibitor (5.4 to 14.3 μg trypsin-chymotrypsin inh/g BPI) and α-amylase inhibitor activity (2.5 to 14.9% inhibition relative to acarbose/mg BPI) were higher in Mexican beans compared to Brazilian beans. Abundant peptides were identified by HPLC-MS/MS with molecular masses ranging from 300 to 1500 Da and significant sequences were SGAM, DSSG, LLAH, YVAT, EPTE and KPKL. Potential bioactivities of sequenced peptides were angiotensin converting enzyme inhibitor (ACE), dipeptidyl peptidase IV inhibitor (DPP-IV) and antioxidant capacity. Peptides from common bean proteins presented potential biological activities related to control of hypertension and type-2 diabetes.

The objective of this research was to determine the bioactive properties of the released peptides from commercially available precook common beans (Phaseolus vulgaris). Bioactive properties and peptide profiles were evaluated in protein hydrolysates of raw and commercially precooked common beans. Five varieties (Black, Pinto, Red, Navy, and Great Northern) were selected for protein extraction, protein and peptide molecular mass profiles, and peptide sequences. Potential bioactivities of hydrolysates, including antioxidant capacity and inhibition of α-amylase, α-glucosidase, dipeptidyl peptidase-IV (DPP-IV), and angiotensin converting enzyme I (ACE) were analyzed after digestion with pepsin/pancreatin. Hydrolysates from Navy beans were the most potent inhibitors of DPP-IV with no statistical differences between precooked and raw (IC50 = 0.093 and 0.095 mg protein/mL, respectively). α-Amylase inhibition was higher for raw Red, Navy and Great Northern beans (36%, 31%, 27% relative to acarbose (rel ac)/mg protein, respectively). α-Glucosidase inhibition among all bean hydrolysates did not show significant differences; however, inhibition values were above 40% rel ac/mg protein. IC50 values for ACE were not significantly different among all bean hydrolysates (range 0.20 to 0.34 mg protein/mL), except for Red bean that presented higher IC50 values. Peptide molecular mass profile ranged from 500 to 3000 Da. A total of 11 and 17 biologically active peptide sequences were identified in raw and precooked beans, respectively. Peptide sequences YAGGS and YAAGS from raw Great Northern and precooked Pinto showed similar amino acid sequences and same potential ACE inhibition activity. Processing did not affect the bioactive properties of released peptides from precooked beans. Commercially precooked beans could contribute to the intake of bioactive peptides and promote health., (© 2014 Institute of Food Technologists®)

The objective of this work was to determine the impact of germination of cowpea (Vigna unguiculata), combined with enzymatic hydrolysis on the generation of bioactive peptides with dipeptidyl peptidase IV (DPP-IV) inhibition activity and antioxidant capacity. Germination (25°C, up to 48h) and alcalase hydrolysis (up to 4h) significantly increased antioxidant capacity of cowpea proteins from 293.4 to 993.7μmol TE/g soluble protein (SP). The non-germinated and 1h alcalase hydrolysates showed the highest DPP-IV inhibition (IC 50 =0.58mgSP/mL), after in vitro simulated gastrointestinal digestion. Selected peptides in the hydrolysates were analyzed by computational modeling. The TTAGLLE peptide interacted with S2 (GLU205, GLU206) and S3 (SER209, ARG358, PHE357) pockets of DPP-IV, and it is expected to inhibit DPP-IV by blocking its active site. Cowpea short time germination (24h) and alcalase protein hydrolysis (1h) can be used to produce ingredients with high antioxidant capacity and DPP-IV inhibition., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

Scope: The objective was to compare the anti-inflammatory potential of unprocessed and extruded amaranth pepsin/pancreatin hydrolysates in LPS-induced human THP-1 macrophages-like and mouse RAW 264.7 macrophages focusing on their anti-inflammatory mechanism of action related to NF-κB signaling pathway., Methods and Results: Amaranth hydrolysates were characterized by MS-MS and tested for anti-inflammatory effects on human and mouse macrophages. Peptides found in extruded amaranth hydrolysates displayed antioxidant capacity, angiotensin converting enzyme-inhibitor activity, and dipeptidyl peptidase-IV inhibitor activity. Gly-Pro-Arg peptide was present and reported as antithrombotic. Extruded amaranth hydrolysates (1 mg/mL) significantly reduced tumor necrosis factor alpha secretion in THP-1 and RAW 264.7 cells by 36.5 and 33.5%, respectively; with concomitant reduction in PGE2 (15.4 and 31.4%), and COX-2 (38.1 and 67.6%), respectively. Phosphorylation of IKK-α was significantly reduced by 52.5 and 88.2% leading to reduced phosphorylation of IκB-α (86.1 and 66.2%), respectively; resulting in a reduction in the expression of p65 NF-κB subunits in the nucleus by 64.2% for THP-1 and 70.7% for RAW 264.7 cells., Conclusion: Amaranth hydrolysates inhibited LPS-induced inflammation in human and mouse macrophages by preventing activation of NF-κB signaling. Extrusion improved anti-inflammatory effect of amaranth hydrolysates in both cells, which might be attributed to the production of bioactive peptides during processing., (© 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Ardisia species (Myrsinaceae) are found throughout tropical and subtropical regions of the world. Traditional medicinal uses attributed to Ardisia include alleviation of liver cancer, swelling, rheumatism, earache, cough, fever, diarrhea, broken bones, dysmenorrhea, respiratory tract infections, traumatic injuries, inflammation, pain, snake and insect bites, birth complications and to improve general blood circulation, among others. Ardisia species are rich in polyphenols, triterpenoid saponins, isocoumarins, quinones and alkylphenols. A summary of the uses, potential health benefits, adverse reactions and important bioactive phytochemicals isolated from the Ardisia species is presented. Future research needs to include more toxicological studies, more comprehensive chemical characterization of extracts, bioavailability, extract standardization, investigation of possible herb-drug interactions, plant improvement with regards to bioactivity and composition, and additional human and animal studies to confirm the health-promoting properties claimed for Ardisia species. The information presented here exemplifies the potential of Ardisia species as a source of chemotherapeutic, chemo-modulating and/or chemopreventive agents.

Amaranth seeds are rich in protein with a high nutritional value, but little is known about their bioactive compounds that could benefit health. The objectives of this research were to investigate the presence, characterization, and the anticarcinogenic properties of the peptide lunasin in amaranth seeds. Furthermore, to predict and identify other peptides in amaranth seed with potential biological activities. ELISA showed an average concentration of 11.1 microg lunasin equivalent/g total extracted protein in four genotypes of mature amaranth seeds. Glutelin fraction had the highest lunasin concentration (3.0 microg/g). Lunasin was also identified in albumin, prolamin and globulin amaranth protein fractions and even in popped amaranth seeds. Western blot analysis revealed a band at 18.5 kDa, and MALDI-TOF analysis showed that this peptide matched more than 60% of the soybean lunasin peptide sequence. Glutelin extracts digested with trypsin, showed the induction of apoptosis against HeLa cells. Prediction of other bioactive peptides in amaranth globulins and glutelins were mainly antihypertensive. This is the first study that reports the presence of a lunasin-like peptide and other potentially bioactive peptides in amaranth protein fractions.

Plant polyphenols, as those present in teas, have been associated with several health benefits. In this study, the main objectives were to identify and characterize the phenolic compounds in Ardisia compressa tea (AC) responsible for topoisomerase inhibition using a bioassay directed approach and modern analytical techniques, and to determine the cytotoxicity against human colon carcinoma cells. Inhibition of topoisomerase was determined by yeast and human topoisomerase biochemical assays. Identification and characterization of AC phenolic compounds were carried out using combined HPLC, MS and NMR techniques. Cytotoxicity studies were conducted using two human colorectal adenocarcinoma cell lines, HT-29 and Caco-2. LC-MS analysis of AC confirmed the presence of gallic acid, epicatechin gallate, several proanthocyanidin dimers, kaempferol, naringenin and ardisin derivatives. Topoisomerase II catalytic inhibitory activity of AC was due mainly to phenolic compounds extracted in the butanolic fraction (IC50: 1.33 microg/ml). Purification of this fraction resulted in the isolation of several compounds: peak 10 (IC50: 8.32 microg/ml), peaks 12/14 (IC75: 2.85 microg/ml) and peak 15 (IC50: 7.16 microg/ml). Characterization of peak 15, the most active fraction, led to the isolation of a naringenin isomer (C15H12O5), which had a significantly higher catalytic anti-topoisomerase II activity (IC50: 7.16 microg/ml) than commercial naringenin (IC50: 88.1 microg/ml). AC was cytotoxic to HT-29 (IC50: 57.9+/-11.6 microg/ml) and Caco-2 cells (IC50: 81.0+/-27.5 microg/ml). These findings provide basic information and suggest the potential use of active flavonoids in Ardisia compressa tea as chemopreventive agents.

Plant lectins, a unique group of proteins and glycoproteins with potent biological activity, occur in foods like wheat, corn, tomato, peanut, kidney bean, banana, pea, lentil, soybean, mushroom, rice, and potato. Thus, dietary intakes by humans can be significant. Many lectins resist digestion, survive gut passage, and bind to gastrointestinal cells and/or enter the circulation intact, maintaining full biological activity. Several lectins have been found to possess anticancer properties in vitro, in vivo, and in human case studies; they are used as therapeutic agents, preferentially binding to cancer cell membranes or their receptors, causing cytotoxicity, apoptosis, and inhibition of tumor growth. These compounds can become internalized into cells, causing cancer cell agglutination and/or aggregation. Ingestion of lectins also sequesters the available body pool of polyamines, thereby thwarting cancer cell growth. They also affect the immune system by altering the production of various interleukins, or by activating certain protein kinases. Lectins can bind to ribosomes and inhibit protein synthesis. They also modify the cell cycle by inducing non-apoptotic G1-phase accumulation mechanisms, G2/M phase cell cycle arrest and apoptosis, and can activate the caspase cascade. Lectins can also downregulate telomerase activity and inhibit angiogenesis. Although lectins seem to have great potential as anticancer agents, further research is still needed and should include a genomic and proteomic approach.

The objective of this study was to compare the antioxidant effect of ardisin and epigallocatechin 3-O-gallate (EGCG) in hepatocytes exposed to either benomyl or 1-nitropyrene (1-NP). Rat hepatocytes were incubated in a serum-free medium with non-cytotoxic concentrations of either ardisin (0.27 microg/ml) or EGCG (3 microg/ml), and with either benomyl (35 microg/ml) or 1-NP (0.25 microg/ml). The level of malondialdehyde (MDA) as a marker of lipid peroxidation was determined, as well as the content of glutathione (GSH) and the activities of glutathione peroxidase (GPx) and glutathione reductase (GR). In comparison to the control, the concentration of GSH improved 282% (P<0.05) and 260% (P<0.05) after the cells were pre-incubated with ardisin or EGCG and then exposed to benomyl, respectively. The activity of GPx decreased 55% with ardisin (P<0.05) and 51% with EGCG (P<0.05), and MDA decreased 7% and 23% (P<0.05) with the same treatments. The concentration of GSH also improved when the cells were incubated with either EGCG (49%, P<0.05) or ardisin (83%, P<0.05) simultaneously with 1-NP, relative to 1-NP alone. Moreover, ardisin decreased MDA formation by 65% (p<0.05), and enhanced the activity of GR by 137% (P<0.05). These results suggest that ardisin is a better suppressor of lipid peroxidation induced by benomyl and 1-NP than EGCG. It is concluded that ardisin and EGCG are potent antioxidants that can afford protection against free radical mediated diseases.

Trypsin inhibitors (TI), tannins, and lectins appear to have a role in preventing chronic diseases in humans. The genetic variability of these traits in common bean needs to be ascertained in order to increase levels through breeding. The variability of TI, tannin, and lectins was determined in five bean cultivars grown at five locations in Mexico. TI and tannins contents in colored beans that belong to the Jalisco race were higher (11.1-11.9 trypsin units inhibited (TUI)/mg and 29.0-38.1 mg catechin equivalent (CE)/g, respectively) than cultivars of the Durango race (7.9-8.3 TUI/mg and 16.8-19.9 CE/mg, respectively). Bayo Victoria, a Durango race cultivar, had three times more lectins than levels reported for soybean. Cultivar influenced TI and tannins contents (p < 0.001), whereas site affected lectins (p < 0.001). An increase in levels of TI and tannins could be enhanced through breeding.

Herbal tea preparations of Ardisia compressa (AC) have been used in folk medicine against liver disorders. The objective of this study was to evaluate the in vitro protective effect of an aqueous extract of dry leaves of AC on 1-nitropyrene (1-NP) induced cytotoxicity on rat hepatocytes. Lipid peroxidation (malondialdehyde), antioxidant enzyme activities (glutathione reductase, glutathione peroxidase, superoxide dismutase) and glutathione levels were studied. After 2 h of incubation, 0.25 microg/ml of 1-NP had an approximately 50% cytotoxic effect on hepatocytes. This environmental toxicant also increased malondialdehyde (77%), and glutathione peroxidase (46%), producing a significant consumption of endogenous antioxidant glutathione. (-)Epigallocatechin 3-gallato (EGCG) and AC decreased the viability of hepatocytes after 2 h of incubation at concentrations above 3 microg/ml and 2.52 microg, equivalents of (+)catechin/ml, respectively. A 100% hepatocyte protection was observed when cells were first exposed to AC (2.52 microg, equivalents of (+)catechin/ml), and then followed by 1-NP (0.25 microg/ml). Cells incubated with AC, either simultaneously or before treatment with 1-NP, were protected 75 and 84%, respectively. Cell protection of AC was superior to EGCG. Addition of AC to 1-NP (1:10) modulated superoxide dismutase and glutathione reductase activities (P<0.005), as well as the cellular level of GSH. The results indicate that AC has an antioxidant protective effect on rat hepatocytes when exposed to 1-NP.

Polyphenols in fruits, vegetables (e.g., flavonols like quercetin) and tea (e.g., catechins such as epigallocatechin gallate) are good antioxidants with antimutagenic and anticarcinogenic properties. In the present study, the Salmonella typhimurium tester strain YG1024 was used in the plate-incorporation test to examine the antimutagenic effect of phenolic compounds, extracted from common beans (Phaseolus vulgaris), on 1-NP and B[a]P mutagenicity. Dose-response curves for 1-NP and B[a]P were obtained; the number of net revertants/plate at the peak mutagenic dosage were 880 for 1-NP and 490 for B[a]P. For the antimutagenicity studies doses of 0.1 microg/plate and 2 microg/plate for 1-NP and B[a]P, respectively, were chosen. We obtained a dose-response curve of ellagic acid (EA) against B[a]P and 1-NP mutagenicity. To test the bean extract, a dose of 300 microg/plate of EA was chosen as the antimutagenic control. The EA and bean extracts were not toxic to the bacteria at the concentrations tested. The inhibitory effects of the bean extracts and EA against B[a]P mutagenicity were dose-dependent. The percentages of inhibition produced against B[a]P (2 microg/plate) using 300 microg/plate of EA and for the extracts 500 microg equivalent catechin/plate were 82%, 83%, 81% and 83% for EA, water extract, water/methanol extract and methanol extract, respectively. However, for 1-NP mutagenicity, only the methanolic extract from beans showed an inhibitory effect. These results suggest that common beans, as other legumes, can function as health-promoting foods., (Copyright 1999 Elsevier Science B.V.)

The antioxidant properties of lutein, lycopene and apocarotenoic ester were examined in vitro regarding their capacity to reduce the cytotoxic effect of the T-2 toxin on chicken hepatocytes. The protective effect was evaluated with a reduction of glutathione and lactate dehydrogenase leakage. Cellular damage was observed at a concentration of 5 x 10(-4) m T-2 toxin, and with at least 10(-5) M for all the carotenoids tested. A partial protective effect against mycotoxin was observed when hepatocytes were exposed simultaneously to lutein (10(-6) m) and T-2 toxin (5 x 10(-4) m). Lycopene (10(-6) m) was able to reduce the cytotoxic effect of the T-2 mycotoxin (5 x 10(-4) m) when both we're in contact with cells, either simultaneously or previously exposed to the toxin (incubation time 60 min). The apocarotenoic ester did not protect these cells against the T-2 toxin effect. The results suggest that lutein and lycopene helped maintain the integrity of the cellular membrane structure in the presence of T-2 toxin.

Ellagic acid (EA) is a phenolic compound that exhibits both antimutagenic and anticarcinogenic activity in a wide range of assays in vitro and in vivo. It occurs naturally in some foods such as strawberries, raspberries, and grapes. In the previous work, we used the Salmonella microsuspension assay to examine the antimutagenicity of EA against the potent mutagen aflatoxin B1 (AFB1) using tester strains TA98 and TA100. Briefly, the microsuspension assay was approximately 10 times more sensitive than the standard Salmonella/microsome (Ames) test in detecting AFB1 mutagenicity, and EA significantly inhibited mutagenicity of all AFB1 doses in both tester strains with the addition of S9. The greatest inhibitory effect of EA on AFB1 mutagenicity occurred when EA and AFB1 were incubated together (with metabolic enzymes). Lower inhibition was apparent when the cells were first incubated with EA followed by a second incubation with AFB1, or when the cells were first incubated with AFB1 followed by a second incubation with EA alone, all with metabolic enzymes. The result of these sequential incubation studies indicates that one mechanism of inhibition could involve the formation of an AFB1-EA chemical complex. In the present study, we further examine the effect of EA on AFB1 mutagenicity, but without the addition of exogenous metabolic enzymes. We report the mutagenicity of AFB1 in the microsuspension assay using TA98 and TA100 without the addition of S9. Neither the concentrations of AFB1 (0.6, 1.2, and 2.4 microg/tube) nor the concentrations of EA (0.3, 1.5, 3, 10, and 20 microg/tube) were toxic to the bacteria. The results indicate that AFB1 is a direct-acting mutagen, and that EA inhibits AFB1 direct-acting mutagenicity.