Processing contaminants in wheat-based foods - a systematic review, meta-analysis and bibliometric analysis.

Wheat is one of the main cereals grown around the world and is the basis for several foods such as bread, cakes and pasta. The consumption of these foods raises a concern with food safety, as toxic substances such as acrylamide, 5-hydroxymethylfurfural and polycyclic aromatic hydrocarbons are formed during their processing. To assess the occurrence of processing contaminants in wheat-based foods, a systematic search was carried out in four databases: PubMed, Embase, Web of Science and Scopus. Of the 1479 results, 28 were included for a meta-analysis. Most studies (69.7%) evaluated acrylamide in bread, cookies, and pasta, while PAHs (26.2%) were determined mainly in wheat grains and pasta. HMF was the least determined contaminant (4.1%), with only four studies on cookies included in the meta-analysis. The highest concentration was for acrylamide (136.29 µg·kg-1) followed by HMF (70.59 µg·kg-1) and PAHs (0.11 µg·kg-1). Acrylamide is the main processing contaminant researched, and no studies on the subject have been found in commercial samples in some regions of the world. This result shows a gap in the dates available about process contaminants in wheat-based foods and how the levels can change depending on the process parameters and the ingredients used.

Biological contamination of the common bean (Phaseolus vulgaris L.) and its impact on food safety.

The occurrence of biological contaminants in common beans is a challenge for food safety, as they can affect the bean at different points in the production chain. Their presence can result in damage to the health of consumers through their direct toxic effect or by promoting nutritional deficiencies, in addition to decreasing the crop yield that has an economic impact. In this article, the information available in the literature on the occurrence of biological contaminants in the common bean (Phaseolus vulgaris L.) was organized to identify the main risks to food safety due to biological contamination. Research showed that many studies investigated the effects of microbial contaminants during the farming and harvested of beans and that some strategies have been used to avoid losses. The presence of toxigenic fungi and some mycotoxins have also been reported, indicating that common beans may carry thermostable toxic residues, directly impacting human health. Further studies are needed to identify the role of microorganisms in determining the quality of common beans and to estimate their risks to food safety. HighlightsBeans can be contaminated by biological agents.Plants infected with parasites may be highly susceptible to other contaminants.Micotoxicologic contamination is less prevalent in beans than other grains.There are strategies to decrease the risk of bacterial contamination in beans.

Toxicity evaluation of traditional and organic yerba mate (Ilex paraguariensis A. St.-Hil.) extracts.

Yerba mate (Ilex paraguariensis A. St.-Hil.) is an important source of biologically active compounds with pharmacological potential. The aim of this study was to examine the toxicity of different extracts obtained from either traditional or organic cultivated yerba mate in vitro and in vivo. Aqueous, ethanolic and methanolic extracts were obtained from commercial samples of yerba mate and total phenolic content was determined employing Folin-Ciocalteau reagent. The aqueous extracts presented higher content of total phenols, compared to ethanolic and methanolic extracts, and also demonstrated lower cytotoxicity, which is the basis for testing were carried out only using aqueous extracts. The main phenolic acids found in traditional aqueous (TA) extract were chlorogenic, gallic and protocatechuic acids. Gallic and hydroxybenzoic acids were detected in aqueous cultivated organic (OA) extract. Pretreatment with OA extract (100 µg/ml, 1 hr) was cytoprotective against rotenone-induced toxicity (1 µM). For in vivo toxicity assay, zebrafish embryos were exposed to OA or TA extracts (10-160 µg/ml) at 4 hr post fertilization. TA extract decreased embryos survival in a concentration-dependent manner, reduced the hatching rate at 40 µg/ml, increased edema frequency at 80 µg/ml and altered body curvature at 120 µg/ml. Further, TA extract produced locomotor disorders at concentrations equal to or greater than 10 µg/ml. In contrast, OA extract exhibited no apparent toxic effect on organogenesis and behavior up to 100 µg/ml. In summary, the OA cultivated extract showed the lowest cytotoxicity in vitro, enhanced reduction in rotenone-induced toxicity, and produced less toxicity in zebrafish embryos compared to the TA extract.

Mushroom extract of Lactarius deliciosus (L.) Sf. Gray as biopesticide: Antifungal activity and toxicological analysis.

Monilinia fructicola (Wint.) Honey is a plant pathogenic fungus that infects stone fruits such as peach, nectarine and plum, which are high demand cultivars found in Brazil. This pathogen may remain latent in the host, showing no apparent signs of disease, and consequently may spread to different countries. The aim of this study was to evaluate the activity of hydroalcoholic extract (HydE) obtained from Lactarius deliciosus (L.) Sf. Gray a mushroom, against M. fructicola phytopathogenic-induced mycelial growth. In addition, the purpose of this study was to examine phytotoxicity attributed to HydE using Brassica oleracea seeds, as well as cytotoxic analysis of this extract on cells of mouse BALB/c monocyte macrophage cell line (J774A.1 cell line) (ATCC TIB-67). The L. deliciosus HydE inhibited fungal growth and reduced phytopathogen mycelial development at a concentration of 1.25 mg/ml. Our results demonstrated that the extract exhibited phytotoxicity as evidenced by (1) interference on germination percentage and rate index, (2) decreased root and initial growth measures, and (3) lower fresh weight of seedlings but no cytotoxicity in Vero cell lines. Data suggest that the use of the L. deliciosus extracts may be beneficial for fungal control without any apparent adverse actions on mouse BALB/c monocyte macrophage cell line (J774A.1 cell line) viability.

Phenolic compounds and antioxidant capacity of Pediastrum boryanum (Chlorococcales) biomass.

Bioactive compounds, synthesized by photosynthetic microorganisms, have drawn the attention of the pharmaceutical field. This study aimed at evaluating synthesis and in vitro antioxidant capacity of phenolic compounds produced by a microalgae species P. boryanum, which was grown in six different culture media (standard BG11, modified BG11/MBG11, standard WC, modified WC, WC*2 and basal). The highest concentrations of biomass (1.75 ± 0.01 g.L-1) and phenolic content (3.18 ± 0.00 mg.g-1) were obtained when P. boryanum was grown in MBG11 and phenolic acids were identified: gallic, protocatechuic, chlorogenic, hydroxybenzoic and vanillic ones. All extracts exhibited scavenger activity in the ABTS assay and inhibited peroxidase. However, phenolic compounds from P. boryanum grown in BG11 and MBG11 had the most potent scavenger activity in the DPPH assay. In sum, P. boryanum can be a new source of free phenolic compounds with potential antioxidant activity when grown in MBG11, since it yields high amounts of biomass and phenolic compounds.

Simultaneous distribution of aflatoxins B1 and B2, and fumonisin B1 in corn fractions during dry and wet-milling.

One of the limitations of the use of corn in the food chain is its contamination with mycotoxins. Reduction in their levels can be achieved by processing the grain, which in the case of corn can be achieved by wet or dry milling. The aim of this study was to compare the distribution of aflatoxins B1 and B2, and fumonisin B1 in corn fractions obtained by dry and wet milling, aiming to identify conditions to mitigate the risk of exposure to these contaminants. Naturally, contaminated corn kernels were subjected to laboratory milling. The wet-milling conditions containing 1% lactic acid in the steeping solution and 18 h of steeping were the most efficient for mycotoxin reduction in the endosperm fraction, reducing aflatoxins B1 and B2 contamination to levels below the limit of quantification. Dry-milling reduced the concentration of these mycotoxins in the endosperm (98-99%). Fumonisin B1 contamination increased in the germ and pericarp fraction by more than three times in both dry and wet milling. Dry-milling reduced fumonisin B1 contamination in the endosperm to levels below the limit of quantitation. Wet and dry milling processes can be an efficient control method to reduce aflatoxins and fumonisin in the corn endosperm fraction. Supplementary Information: The online version contains supplementary material available at 10.1007/s13197-022-05373-9.

Use of natural resources from Southern Brazil as a strategy to mitigate fungal contamination.

Contamination of food by fungi can result in changes in sensory characteristics, as well as rapid reduction in quality and consequently the infeasibility of using contaminated material. In addition, contamination can pose a danger to public health, as in addition to decreasing the availability of nutrients, some fungal species can produce toxic substances. Much research has explored the use of natural resources to prevent or mitigate microbial contamination. Recovery of chemicals from many families from plants and microorganisms has been evaluated. Phenolic compounds are the most studied class on the premise that they have the capacity to inhibit endogenous and exogenous biological degradation processes. In this manuscript, we intend to emphasize the biochemical and experimental evidence of the phenolic compounds present in natural resources from the South of Brazil that have potential to be used in strategies to mitigate the consequences of fungal contamination. The crude phenolic extracts from natural resources (plant portion and microorganisms) of the Southern Brazilian region should be better exploited, to propose strategies to scale up their application in food industries because they have demonstrated an ability to inhibit fungal development without promoting stress and consequent mycotoxin production.

Defatted Rice Bran as a Potential Raw Material to Improve the Nutritional and Functional Quality of Cakes.

Cakes are the most popular bakery items around the world because they are easy to consume and affordable. Their baking characteristics and consumers' healthy habits have driven the adoption of new ingredients and technologies to improve their functionality. This study aimed to develop cakes in which wheat flour was replaced by different amounts of defatted rice bran and to evaluate their physicochemical composition, nutritional and technological properties, and sensory profile. The use of defatted rice bran in cakes promoted an increase in fiber content, phenolic compounds and antioxidant capacity, besides decreasing their energy value. The formulation with 30% defatted rice bran exhibited high acceptance and 35% of the judges declared that they would consume the product at least once a week, if it could be found on the market. Results showed that defatted rice bran is a potential raw material that could be used in bakery products, as a cheap way to improve their nutritional quality without affecting consumer acceptability.

Antioxidant and antifungal activity of phenolic compounds and their relation to aflatoxin B1 occurrence in soybeans (Glycine max L.).

BACKGROUND: Soybean is widely used in food formulations; however, few studies on fungal or mycotoxin contamination have been undertaken. Free, conjugated, and bound phenolic compounds, and their antioxidant and antifungal potential, were therefore evaluated together with the occurrence of aflatoxin B1 (AFB1 ) in soybeans. RESULTS: The conjugated and bound phenolic soybean extracts were more efficient for the inhibition of the 2,2 diphenyl-1-picryl-hydrazyl (DPPH) radical, the peroxidase enzyme, and the fungal α-amylase enzyme. Aflatoxin B1, detected at low levels (0.96 to 1.67 ng g-1 ), confirmed the protective effect of soybean phenolic compounds against mycotoxigenic contamination. Principal component analysis confirmed that syringic, p-hydroxybenzoic, p-coumaric acids and vanillin were essential for antioxidant and antifungal activities. CONCLUSION: This study presented new insights into the functionality of phenolic compounds in soybeans, regarding their potential to protect the crops naturally against fungal contamination, avoiding aflatoxin production, as attested by the correlations between phenolic compounds and antioxidant mechanisms. © 2019 Society of Chemical Industry.

Nannochloropsis sp. and Spirulina sp. as a Source of Antifungal Compounds to Mitigate Contamination by Fusarium graminearum Species Complex.

Phenolic (free, conjugated and bound) and carotenoid extracts from microalgae Nannochloropsis sp. and Spirulina sp. were investigated regarding their potential to mitigate contamination by Fusarium complex fungal pathogens. Free phenolic acid extracts from both microalgae were the most efficient, promoting the lowest mycelial growth rates of 0.51 cm day- 1 (Spirulina sp.) and 0.78 cm day- 1 (Nannochloropsis sp.). An experiment involving natural free phenolic acid extracts and synthetic solutions was carried out based on the natural phenolic acid profile. The results revealed that the synthetic mixtures of phenolic acids from both microalgae were less efficient than the natural extracts at inhibiting fungal growth, indicating that no purification is required. The half-maximal effective concentration (EC50) values of 49.6 µg mL- 1 and 33.9 µg mL- 1 were determined for the Nannochloropsis and Spirulina phenolic acid extracts, respectively. The use of phenolic extracts represents a new perspective regarding the application of compounds produced by marine biotechnology to prevent Fusarium species contamination.

Ozone technology to reduce zearalenone contamination in whole maize flour: degradation kinetics and impact on quality.

BACKGROUND: Maize is one of the most important cereals. It is used for different purposes and in different industries worldwide. This cereal is prone to contamination with mycotoxins, such as zearalenone (ZEN), which is produced mainly by Fusarium graminearum, F. culmorum and F. equiseti. Toxin production under highly moist conditions (aw > 0.95) is exacerbated if there are alternations between low temperatures (12-14 °C) and high temperatures (25-28 °C). Even if good production practices are adopted, mycotoxins can be found in several stages of the production chain. For this reason, an alternative to reducing this contamination is ozonation. This study evaluated the reduction of ZEN in naturally contaminated whole maize flour (WMF) treated with 51.5 mg L-1 of ozone for up to 60 min. Pasting properties, peroxide value, and fatty acid composition were also evaluated. RESULTS: Zearalenone degradation in ozonated WMF was described by a fractional first-order kinetic, with a maximum reduction of 62.3% and kinetic parameter of 0.201 min-1 in the conditions that were evaluated. The ozonation process in WMF showed a decrease in the apparent viscosity, a decrease in the proportion of linoleic, oleic, and α-linolenic fatty acids, an increase in the proportion of palmitic acid, and an increase in the peroxide value. CONCLUSION: Ozonation was effective in reducing ZEN contamination in WMF. However, it also modified the pasting properties, fatty acid profile, and peroxide value, affecting functional and technological aspects of WMF. © 2019 Society of Chemical Industry.

The action of probiotic microorganisms on chemical contaminants in milk.

Consumption of milk and its derivatives is an important food habit in the diet of all age groups. However, there has been increasing concern about physical, biological (pathogenic or spoilage microorganisms) and chemical (metals, pesticides and mycotoxins) contaminants in milk and dairy products. Considering the high levels of consumption, it is important that milk and dairy products are free from toxic compounds. Microbial degradation as a strategy for chemical decontamination is an emerging biotechnological approach that is considered a safe and inexpensive practice. The decontaminant activity of probiotic microorganisms is associated with fermentation, antibiosis and the ability of the microbial cell wall to bind to the contaminant. Exploiting the potential of microorganisms for chemical decontamination will further leverage its application in the food industry.

Free phenolic compounds extraction from Brazilian halophytes, soybean and rice bran by ultrasound-assisted and orbital shaker methods.

In several countries halophytes are commercially cultivated in low saline or even irrigated with seawater, as well as with saline aquaculture effluent, like a sea asparagus Sarcocornia ambigua, that show a biotechnological potential for bioactive compounds production. However, their recovery from matrix is sometimes inefficient because the lignocellulosic materials difficult the solvent action when drastic conditions are not applied. The ultrasound-assisted extraction (UAE) was optimized by a central composite rotational design for recovery free phenolic compounds (FPC) from the sea asparagus S. ambigua. Optimum conditions were validated and compared with orbital shaker extraction for S. ambigua, other Brazilian halophytes (Apium graveolens, Myrsine parvifolia, Paspalum vaginatum, and Schinus terebinthifolius), soybean and rice bran. Except for P. vaginatum, soybean and rice bran, UAE yielded 18-29% higher FPC than that of the orbital shaker. Besides this analytical performance UAE method optimized is faster than the orbital shaker, providing shorter exposure of the analyst to the extractor solvent and applicable in matrices with different compositions. It was also demonstrated that halophytes species showed to be good natural sources of FPC in a better way as soybean and rice bran. This work was the first to report FPC in M. parvifolia and P. vaginatum.

Inhibition of Enzymatic and Oxidative Processes by Phenolic Extracts from Spirulina sp. and Nannochloropsis sp.

This study investigates the capacity of phenolic extracts from microalgae Nannochloropsis sp. and Spirulina sp. to inhibit enzymes and free radical activities, intending to find an innovative way to slow down food damage. HPLC-UV and LC-MS/MS served to determine and confirm, respectively, the phenolic acid profiles in the soluble methanolic (free phenolic) and ethanolic (conjugated phenolic) fractions, and after hydrolysis (bound phenolic fractions). Different procedures measured the antioxidant activity of the extracts to estimate the minimal concentration for the protective effect, stability and versatility of activity. The ability to inhibit the oxidative process (ABTS and DPPH), α-amylase and peroxidase activities were estimated as specific inhibition (%/(min·µg)) for better comparison between the phenolic sources. The phenolic acid mass fractions in the free phenolic extracts from Spirulina sp. and Nannochloropsis sp. were 628 and 641 µg/g, respectively. Phenolic extract from Nannochloropsis sp. showed the highest value of ABTS inhibition (1.3%/(min·µg)) and highest inhibition of peroxidase activity (0.4%/(min·µg)). The extract from Spirulina sp. was a better inhibitor of α-amylase activity (0.07%/(min·µg)). Therefore, the phenolic extracts from the edible microalgae may be applied in food industry as natural protector against endogenous and exogenous hydrolytic and oxidative processes.

Antifungal effect of phenolic extract of fermented rice bran with Rhizopus oryzae and its potential use in loaf bread shelf life extension.

BACKGROUND: In this study the antifungal potential of a phenolic extract obtained from rice bran fermented with Rhizopus oryzae CECT 7560 and its application in the elaboration of bread was assessed. RESULTS: Eighteen compounds with antifungal potential were identified by LC-ESI-qTOF-MS in the extract: organic acids, gallates and gallotannins, flavonoids, ellagic acid and benzophenone derivatives. The extract was active against strains of Fusarium, Aspergillus and Penicillium, with minimum inhibitory concentration ranging from 390 to 3100 µg mL-1 and minimum fungicidal concentration variable from 780 to 6300 µg mL-1 . The strains that were most sensitive to the phenolic extract were F. graminearum, F. culmorum, F. poae, P. roqueforti, P. expansum and A. niger. The phenolic extract added at 5 and 1 g kg-1 concentrations in the preparation of bread loaves contaminated with P. expansum produced a reduction of 0.6 and 0.7 log CFU g-1 . The bread loaves treated with calcium propionate and 10 g kg-1 of the phenolic extract evidenced an improvement in their shelf lives of 3 days. CONCLUSION: The phenolic extract assessed in this study could be considered as an alternative for inhibiting toxigenic fungi and as a substitute for synthetic compounds in food preservation. © 2018 Society of Chemical Industry.

Characterization and application of the enzyme peroxidase to the degradation of the mycotoxin DON.

Deoxynivalenol (DON), one of the main mycotoxins found in food matrices, has high level of toxicity. This study aimed to characterize the peroxidase enzyme extracted from rice bran to be applied to the biodegradation of DON in order to evaluate the potential peroxidase (PO) from rice bran (RB) has to degrade DON in optimal conditions. Purification and recovery factors of PO extracted from RB and purified by three-phase partitioning were 5.7% and 50%, respectively. PO had the highest level of activity in the phosphate buffer 5 mM pH 5.5 in both crude and purified forms, whose reaction temperatures were 25°C and 10°C. At the end of production, purification and characterization steps, specific activities of the bran were 115.79 U mg-1 and 4363 U g-1. Reduction in the mycotoxin DON in optimal conditions determined for PO from RB was 20.3%, a promising result when the aim is to adequate mycotoxicological levels to foods.

Effect of natural compounds on Fusarium graminearum complex.

BACKGROUND: A search is underway for new solutions to counter farm loss caused by fungal contamination of grains, since the active agents of fungicides can remain in the environment and contribute to the development of resistant and toxigenic species. In this study, the antifungal activity of natural compounds (γ-oryzanol, phenolic extract of neem seeds and of rice bran) was assessed on three toxigenic strains of Fusarium graminearum isolated from wheat, rice and barley. Their efficacy was compared to that of synthetic fungicides. The halo diameters were measured and the susceptible pathways were determined by the levels of structural compounds and activities of enzymes involved in the primary metabolism of the microorganisms. Moreover, mycotoxin production and gene expression were examined. RESULTS: Phenolic extracts were more effective at inhibiting F. graminearum than was γ-oryzanol, as evidenced by the minimum inhibitory concentration. This work contributed to the elucidation of the mechanism of action of natural antifungal agents. CONCLUSION: Natural antifungals effectively inhibited fungal growth, especially via the inactivation of the enzymatic systems of F. graminearum. Natural antifungals inhibited mycotoxin production by the fungi. A correlation between the levels of deoxynivalenol and the expression of Tri5 gene was observed, indicating that the natural compounds could be considered alternatives to synthetic antifungals. © 2015 Society of Chemical Industry.

Inhibition of Fusarium graminearum growth and mycotoxin production by phenolic extract from Spirulina sp.

Fusarium graminearum is a fungal species complex pathogenic occurring worldwide, mainly associated with cereal crops. The most important Fusarium mycotoxins are fumonisins, zearalenone and trichothecenes. The availability of efficient control measures that are less harmful to both the environment and the consumers is urgent. For such, phenolic acids (PAs) from natural sources are known to reduce fungal contaminations. This work aimed to identify the PAs present in a culture extract of Spirulina algae (strain LEB-18) and evaluate its effect on mycelial growth rate, glucosamine level, amylase activity and mycotoxin production by four strains of two lineages of F. graminearum. Results showed that amendment of potato dextrose media with LEB-18 extract (3% w/v), which was mainly composed by gallic acid, greatly reduced radial growth of fungal colonies compared to media containing a single PA and the control. Also, average reductions of 40% and 62% in the glucosamine levels and the amylase activity were observed. In general, the LEB-18 extract and the PAs reduced mycotoxin concentration, with an average reduction of 68% for the trichothecene mycotoxins deoxynivalenol and nivalenol.

Pasta cooking influence on in vitro bioaccessibility of type B trichothecenes, acrylamide and hydroxymethylfurfural.

The study evaluated the effect of cooking time on the levels of type B trichothecenes (TCTB), acrylamide (AA) and hydroxymethylfurfural (HMF) in semolina pasta and their bioaccessibilities in order to propose strategies to reduce the daily exposure of these natural and processing contaminants. Three brands of commercial pasta were submitted to different cooking times (7, 10 and 13 min). Subsequently, the in vitro bioaccessibility trials, permeation across the intestinal membrane and estimation of daily exposure were carried out. The lowest cooking time (7 min) resulted in high reductions of TCTB (88%) and AA + HMF (76.7%) contents found on the raw pasta. The concentrations of deoxynivalenol (DON) and AA were higher after the digestion (bioaccessibilities >100%) than after the pasta cooking. About 25.6% of DON and 100% of AA found in the small intestine digestible fraction were able to permeate the intestinal membrane. The risk of exposure was below the recommended safe limits since the estimated daily exposure values were 0.22 µg/kg per body weight/day for DON and 0.26 µg/kg per body weight/day for AA. Therefore, cooking pasta for 7 min at a pasta:water ratio of 1:10 (w/v) mitigates the contaminants and promotes the greater formation of resistant starch.

Processing parameters in breadmaking and bioaccessibility of acrylamide and 5-hydroxymethylfurfural.

This study aimed to evaluate the fate in digestive steps, bioaccessibility and diffusion of acrylamide (AA) and 5-Hydroxymethylfurfural (5-HMF) in bread samples produced under different processing parameters. AA and 5-HMF were determined in every sample ready-to-eat, after every digestion step and in the digested after crossing the dialysis membrane. The contaminants were extracted by QuEChERS method and determined by HPLC-PDA. Doubling fermentation time (from 60 to 120 min) increased the level of AA by 1.2-fold, and it decreased the level of 5-HMF by 1.4-fold. A combination of 60 min fermentation and 20 min baking led to the lowest levels of AA (1.71 mg/kg) and 5-HMF (0.50 mg/kg). There was no increase in AA level in the gastric stage however, the 5-HMF level increased. Both contaminant levels had increased in the intestinal stage. This fact showed that the determination of the contaminants in the ready-to-eat product did not reflect their actual bioaccessibility because the digestive enzymes and pH variation may affect the release and detection of AA and 5-HMF accumulated in the baking stage. The initial levels of 5-HMF were correlated to the baking time, and initial levels of AA were correlated to the fermentation time. From the bioaccessible levels of AA and 5-HMF, approximately 90 % (5 mg/kg) and 100 % (6.5 mg/kg) crossed the dialysis membrane respectively. Initial and bioaccessible levels of AA were above the security recommendations for bread (50 µg/kg), which is a concern considering the daily consumption of this food. This study showed that focusing on a combination of processing parameters could be a promising strategy to decrease the bioaccessibility of both contaminants in bread.