A natural approach to combating antibiotic-resistant pathogens in livestock: Hibiscus sabdariffa-derived hibiscus acid as a promising solution.

We examined the antibacterial efficacy of streptomycin, hibiscus acid, and their combination against multidrug-resistant Shiga-toxin-producing Escherichia coli (STEC) and Salmonella Typhimurium in mice. We determined the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) for streptomycin, hibiscus acid, and their combination against STEC and Salmonella. Fifteen sets of six mice in each set were utilised: six groups were orally exposed to 4 log10 colony forming units (CFUs) of S. Typhimurium and another six to STEC, and three acted as the controls. Six hours post-inoculation, specific groups of mice received either oral solutions containing hibiscus acid at 5 and 7 mg/ml; streptomycin at 50 and 450 µg/ml; hibiscus acid/streptomycin (5 mg/ml hibiscus acid and 50 µg/ml streptomycin); or isotonic saline. The study determined the MIC and MBC of 7 mg/ml of hibiscus acid; 300 and 450 µg/ml of streptomycin; and two concentrations of hibiscus/streptomycin (3 mg/ml / 20 µg/ml and 5 mg/ml / 50 µg/ml). Interestingly, the mice that were infected and subsequently treated with hibiscus acid at 7 mg/ml alone or in conjunction with streptomycin did not have either STEC or Salmonella in their faecal samples, and none of the mice died. In contrast, the untreated mice and those exclusively treated with streptomycin had the pathogens present in their stool, leading to the mortality of all the subjects.

Presence of Indicator Bacteria and Occurrence of Potentially Pathogenic Nontuberculous Mycobacteria Species in Packaged Ice Cubes in Central Mexico.

This study aimed to determine the bacteriological quality and presence of diarrheagenic Escherichia coli pathotypes (DEP) and nontuberculous mycobacteria (NTM) species in 85 packaged ice samples from 12 different states of central Mexico. Three samples had a pH of 9.8 and therefore fell outside of the acceptable range for pH. All samples were positive for aerobic-mesophilic bacteria, with limits ranging from 1 to 3.47 log CFU/mL. In total, 35, 11, and 3 ice samples were positive for total coliforms (TC), fecal coliforms (FC), and E. coli, respectively. In the samples, the TC concentration ranged from <1.1 to >23 MPN/100 mL and from <1.1 to 23 MPN/100 mL for FC and E. coli. In total, 38 (44.7%) ice samples were outside of Mexico's official guidelines. None of the 12 E. coli strains isolated from the three ice samples belonged to DEP. NTM were recovered from 20 ice samples and included M. neoaurum (n = 7), M. porcinum (n = 2), M. flavescens (n = 2), M. fortuitum (n = 1), M. abscessus (n = 1), M. senegalense (n = 1), M. conceptionense (n = 1), and M. sp. (n = 1). In the remaining four samples, two NTM were isolated simultaneously. Thus, we recommend that producers should evaluate the microbiological quality of purified water used as a raw material as well as that of the final product, the ice should be packed in thick bags to avoid stretching and tearing during transportation or storage to prevent environmental contamination of ice, personnel involved in the production, and handling of ice should be trained in relative hygiene matters and how ice-machines should be cleaned and disinfected and the implementation of hazard analysis and critical control points must be applied throughout the chain of production. Finally, regular inspection by the authorities is also of great importance. These recommendations can be applied in different countries with low microbiological quality packaged ice.

Incorporation of germinated lupin into corn-based extrudates: Focus on starch digestibility, matrix structure and physicochemical properties.

The research aimed to assess the effects of incorporating germinated Lupinus angustifolius flour into corn extrudates for different periods (3, 5, and 7 days), focusing on starch digestibility, morphological structure, thermal, and pasting properties. Extrudate with germinated lupinus flour for 7 days (EG7) significantly increased the content of slowly digestible starch up to 10.56% (p < 0.05). Crystallinity increased up to 20% in extrudates with germinated flour compared to extrudates with ungerminated flour (EUG), observing changes at the molecular level by FTIR that impact the thermal and pasting properties. X-ray diffraction revealed angles of 2θ = 11.31, 16.60, 19.91, and 33.04 as a result of the germination and extrusion processes. Microstructural analysis indicated starch-protein interactions influencing changes in calorimetry, viscosity, X-ray diffraction, and digestibility. PCA allowed establishing that the addition of germinated flours significantly affected the properties and microstructural characteristics of extruded products, potentially affecting digestibility and nutritional quality.

Hibiscus Sabdariffa L. Extract as a Natural Additive in Food Packaging Biodegradable Films to Improve Antioxidant, Antimicrobial, and Physicochemical Properties.

In this study, biodegradable active films were prepared from potato starch and polyvinyl alcohol at different proportions, mixed with acetone extract of Hibiscus sabdariffa L. (HS) and using glycerol as a plasticizer. Functional properties, antimicrobial, and antioxidant capacity were evaluated. Potato starch films with a proportion of polyvinyl alcohol up to 50% and HS extract had significant antioxidant capacity and antibacterial effect against most of the analyzed strains. Adding polyvinyl alcohol (PVOH) and HS extract improved the mechanical performance and reduced water vapor permeability of the materials. The active biobased films with HS extract presented good physicochemical, antimicrobial, and antioxidant properties. These materials are considered as suitable for food packaging, and the active compounds in the roselle extract are a natural antibacterial option for the food area. The materials based entirely on biodegradable products are an excellent alternative when developing and marketing biobased materials, minimizing the environmental impact of food packaging.

Probiotics, as Adjuvant Therapy and Preventive Measure on Progression, and Complications of Head and Neck Cancer.

BACKGROUND: Preclinical and clinical evidence implies that destructive therapies in local and malignant tissue are frequently used on patients with head and neck cancer. Consequently, the microbiome of the treated and adjacent regions is affected. Disruption of the normal microbiome plays an important role not only in the disease progression but also in its emergence, therefore new therapies involving probiotics, prebiotics, and synbiotics have been developed to control or regulate this microbial disruption. OBJECTIVE: This review aims to describe the current and potential uses of probiotics at different stages of development of head and neck squamous cell carcinoma, as an adjuvant therapy to prevent common complications such as radiation-induced oral mucositis (RIOM) and its role in other areas. METHODS: Currently, there is no widely effective strategy to treat or prevent this kind of cancer. Surgery, radiation therapy, and chemotherapy are the three main treatments for head and neck cancer. Some therapies can also cause long-term health problems, or complications which might change the way you eat, talk, hear and breathe. RESULTS: The main uses for which probiotics have been studied are: Prevention and reduction of severity of RIOM, change in dental plaque to reduce dysbiosis, and reduction of complications in post-operated patients. Potential uses of probiotics include the reduction of disease initiation and progression by reducing local inflammation caused by bacteria and other organisms. CONCLUSION: The incidence and severity of RIOM may be lessened by probiotics. To establish its uses in additional clinical settings, though, more studies are necessary.

Antimicrobial Effects of Aqueous Extract from Calyces of Hibiscus sabdariffa in CD-1 Mice Infected with Multidrug-Resistant Enterohemorrhagic Escherichia coli and Salmonella Typhimurium.

To determinate the antimicrobial effect of chloramphenicol and aqueous extract against multidrug-resistant enterohemorrhagic Escherichia coli (EHEC) and Salmonella enterica serovar Typhimurium in CD-1 mice. Aqueous extract was isolated from Hibiscus sabdariffa calyces. The minimum inhibitory concentration (MIC) and the minimum bactericidal concentration (MBC) of chloramphenicol and aqueous extract were determined for EHEC and S. Typhimurium. Nine groups of six mice each were formed. Three groups were inoculated orally with 1 × 104 colony-forming units (CFU) of S. Typhimurium, three groups were inoculated with 1 × 104 CFU of EHEC and the remaining three groups were not inoculated. Six hours postinoculation, the mice of some groups were orally administered solutions of aqueous extract (50 mg/mL), chloramphenicol (82 µg/mL), or isotonic saline. The EHEC and S. Typhimurium concentration in all mice feces was determined. For both pathogens, the MIC and MBC values of aqueous extract were 20 y 50 mg/mL, respectively; for chloramphenicol, they were between 17.5 and 82 µg/mL. EHEC and S. Typhimurium were not detected in the feces of mice that were administered aqueous extract on the 2nd and 3rd days posttreatment. Furthermore, these mice recovered from the infection. In contrast, in mice not treated, or treated with chloramphenicol alone, pathogens were isolated from their feces throughout the study, and some mice died. The H. sabdariffa calyx extracts could be an alternative to control multidrug-resistant bacteria in humans and animals.

Characterization and Evaluation of the Probiotic Potential In Vitro and In Situ of Lacticaseibacillus paracasei Isolated from Tenate Cheese.

ABSTRACT: The objectives of this investigation were (i) to isolate bacteria from various foods (dairy products, fruits, and vegetables) and evaluate their probiotic potential and (ii) to select, identify, and characterize the bacterial strain(s) with the highest probiotic potential. From 14 food samples, 117 bacterial strains were isolated; however, only 42 (T1 to T42) had the correct characteristics (gram positive, coccoid, and bacilliform) and were catalase and oxidase negative to be considered presumptive lactic acid bacteria (LAB). The antagonistic activity of the 42 strains was evaluated against Escherichia coli (O157:H7E09), Listeria monocytogenes (ATCC 19115), Staphylococcus aureus (ATCC 25923), and Salmonella enterica serotype Typhimurium (ATCC 14028). The nine strains with the highest antagonistic activity were recovered from the following foods: pulque (T1), sprouted beans (T26), Ranchero cheese (T30, T31, T32, T33, T35, and T36), and Tenate cheese (T40). The inhibition zones on culture and sensitivity plates were 17.0 ± 1.2 to 19.3 ± 2.8 mm in diameter. Based on the antagonistic activity against pathogenic bacteria and resistance to low pH and bile salts, strain T40 had the highest probiotic potential. A 16S rRNA technique was used to identify strain T40 as Lacticaseibacillus paracasei (renamed from Lactobacillus paracasei in April 2020). This strain had no resistance to ampicillin, gentamicin, erythromycin, and tetracycline. The antagonistic activity was evaluated in situ (fresh cheese) against pathogenic bacteria, supporting the probiotic potential of L. paracasei. Isolates of this LAB recovered from Tenate cheese had characteristics of a probiotic microorganism with high potential for use in food technology.

Comparison of the Antibacterial Activity and Effect on Membrane Permeability of Hibiscus Acid and a Commercial Chlorhexidine Mouthrinse Against Pathogenic Oral Bacteria and Determination of Hibiscus Acid Toxicity.

The main aim of this study was to determine and compare the antimicrobial effect of hibiscus acid and a commercial 0.12% (w/v) chlorhexidine mouthrinse against Streptococcus mutans, Streptococcus sanguinis, Capnocytophaga gingivalis, and Staphylococcus aureus, and to determine the effect on bacterial cell membrane permeability and the toxicity of hibiscus acid in a mouse model. Hibiscus acid was obtained from acetone extract of Hibiscus sabdariffa calyces. Chlorhexidine (0.12% w/v) mouthrinse was purchased from a local pharmacy. The antimicrobial activity of hibiscus acid and mouthrinse were determined using the gel diffusion technique. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of the solutions were determined using the broth dilution method. The effect on bacterial cell membrane permeability of hibiscus acid and mouthrinse was determined by crystal violet assay. The toxicity of hibiscus acid was investigated in a mouse model (registration number: UAEH2019-A1-S-8288). Hibiscus acid and mouthrinse showed antibacterial activity against all oral pathogenic bacteria. However, hibiscus acid showed a lower antibacterial effect compared with chlorhexidine mouthrinse. The MIC and MBC for hibiscus acid were 3 and 5 mg/mL, respectively, and was between 30 and 50 µg/mL for mouthrinse. The crystal violet test results indicate that hibiscus acid and mouthrinse alter the permeability of the bacterial membrane. Finally, hibiscus acid did not show toxicity in mouse studies.

Antivirulence Activity of a Dietary Phytochemical: Hibiscus Acid Isolated from Hibiscus sabdariffa L. Reduces the Virulence of Pseudomonas aeruginosa in a Mouse Infection Model.

Hibiscus sabdariffa L. (Hs) calyxes, rich in organic acids, are included in diets in different countries. In recent years, some phytochemicals have been shown to reduce bacterial virulence at sublethal concentrations by interfering with quorum sensing (QS) systems. Therefore, in this study the antivirulence properties of Hs calyxes and two γ-lactones (hibiscus acid [HA] and its methyl ester) in Pseudomonas aeruginosa were analyzed. Acetone and methanol extracts of Hs showed anti-QS activity by inhibiting violacein production (60% to 80% with 250 µg/mL). In molecular docking analysis, the γ-lactones registered a good binding score, which suggests strong interaction with the active site of LasR protein. To verify their effect in vitro, they were isolated from Hs and evaluated in six QS-regulated phenotypes, as well as in ExoU toxin that is released by the type III secretion system (T3SS). At 500 µg/mL they reduced alkaline protease (29-52%) and elastase (15-37%) activity, biofilm formation (∼75%), and swarming (50%), but there was no effect on pyocyanin production, hemolytic activity, or type III secretion. In a mouse abscess/necrosis model, HA at sublethal concentrations (15 and 31.2 µg/mL) affected infection establishment and prevented damage and systemic spread. In conclusion, HA is the first molecule identified with antivirulence properties in Hs with the potential to prevent infections caused by P. aeruginosa.

Covalent Functionalization of Graphene Oxide with Fructose, Starch, and Micro-Cellulose by Sonochemistry.

In this work, we report the synthesis of graphene oxide (GO) nanohybrids with starch, fructose, and micro-cellulose molecules by sonication in an aqueous medium at 90 °C and a short reaction time (30 min). The final product was washed with solvents to extract the nanohybrids and separate them from the organic molecules not grafted onto the GO surface. Nanohybrids were chemically characterized by Fourier-transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), and Raman spectroscopy and analyzed by thermogravimetric analysis (TGA), scanning electron microscopy (SEM), and X-ray diffraction (XRD). These results indicate that the ultrasound energy promoted a chemical reaction between GO and the organic molecules in a short time (30 min). The chemical characterization of these nanohybrids confirms their covalent bond, obtaining a grafting percentage above 40% the weight in these nanohybrids. This hybridization creates nanometric and millimetric nanohybrid particles. In addition, the grafted organic molecules can be crystallized on GO films. Interference in the ultrasound waves of starch hybrids is due to the increase in viscosity, leading to a partial hybridization of GO with starch.

Comparison of the Antimicrobial Activity of Hibiscus sabdariffa Calyx Extracts, Six Commercial Types of Mouthwashes, and Chlorhexidine on Oral Pathogenic Bacteria, and the Effect of Hibiscus sabdariffa Extracts and Chlorhexidine on Permeability of the Bacterial Membrane.

To determine and compare the antimicrobial effect of Hibiscus sabdariffa calyx extracts, six types of commercial mouthwashes, and chlorhexidine on Streptococcus mutans, Streptococcus sanguinis, Capnocytophaga gingivalis, and Staphylococcus aureus. Two varieties of H. sabdariffa cultivated in Mexico were used. Aqueous, methanolic, ethanolic, acetonic, and ethyl acetate extracts were obtained from H. sabdariffa calyces. Six different types of mouthwash (Astringosol®, Colgate plax-ice-infinity®, Crest pro-health®, Dental max®, Equate®, and Listerine zero®) and chlorhexidine (0.12%) were purchased at a pharmacy. The antimicrobial activity of the H. sabdariffa calyx extracts, mouthwashes, and chlorhexidine was determined by the agar disc diffusion technique. The minimum inhibitory concentration (MIC) and the minimum bactericidal concentration (MBC) of all solutions were determined by the broth dilution method and the pour plate technique, respectively. Also, the effect of H. sabdariffa extracts and chlorhexidine on permeability of the bacterial membrane was determined by the violet crystal assay. All H. sabdariffa calyx extracts and chlorhexidine showed antibacterial activity against all oral pathogenic bacteria. The mouthwashes showed lower antibacterial effect than H. sabdariffa extracts and chlorhexidine. Dental max showed no antibacterial effect. The MICs and MBCs, respectively, for H. sabdariffa extracts were between 5-20 and 10-20 mg/mL; and for chlorhexidine, between 3-4 and 3-5 mg/mL. For the Listerine®, the MIC and MBC values were between 20-25 and 25-33 mg/mL, respectively. The results of the crystal violet test indicate that H. sabdariffa calyx extracts and chlorhexidine alter the permeability of the bacterial membrane. All H. sabdariffa extracts and chlorhexidine showed significantly greater antimicrobial effect than mouthwashes. This is the first report in which the antimicrobial effect of the H. sabdariffa calyx extracts, mouthwashes, and chlorhexidine is compared.

Organic Acids from Roselle (Hibiscus sabdariffa L.)-A Brief Review of Its Pharmacological Effects.

Roselle (Hibiscus sabdariffa L.), also known as jamaica in Spanish, is a perennial plant that grows in tropical and subtropical regions, including China, Egypt, Indonesia, Mexico, Nigeria, Thailand, and Saudi Arabia. It has a long history of uses, mainly focused on culinary, botanical, floral, cosmetic, and medicinal uses. The latter being of great impact due to the diuretic, choleretic, analgesic, antitussive, antihypertensive, antimicrobial, immunomodulatory, hepatoprotective, antioxidant, and anti-cancer effects. These therapeutic properties have been attributed to the bioactive compounds of the plant, mainly phenolic acids, flavonoids, anthocyanins, and organic acids (citric, hydroxycitric, hibiscus, tartaric, malic, and ascorbic). Most literature reviews and meta-analyses on the therapeutic potential of Hibiscus sabdariffa L. (Hs) compounds have not adequately addressed the contributions of its organic acids present in the Hs extracts. This review compiles information from published research (in vitro, in vivo, and clinical studies) on demonstrated pharmacological properties of organic acids found in Hs. The intent is to encourage and aid researchers to expand their studies on the pharmacologic and therapeutic effects of Hs to include assessments of the organic acid components.

Hibiscus Acid and Chromatographic Fractions from Hibiscus Sabdariffa Calyces: Antimicrobial Activity against Multidrug-Resistant Pathogenic Bacteria.

The anti-microbial properties of acetone extracts from Hibiscus sabdariffa calyces, fractions isolated by silica gel chromatography and hibiscus acid purified from some of these fractions and additionally identified by nuclear magnetic resonance spectroscopy, mid-infrared spectroscopy and X-ray diffraction, were studied against both multidrug-resistant Salmonella strains and pathogenic Escherichia coli bacteria. Gel diffusion was used to determine the anti-microbial effects. The mode of action of hibiscus acid was determined by crystal violet assay. Hibiscus acid and 17 of the 25 chromatographic fractions obtained, displayed an anti-microbial effect against all bacterial strains tested. Hibiscus acid showed a greater anti-microbial effect than the acetone extract against most of the bacteria strains, while chromatographic fractions IX-XIV exerted the greatest anti-microbial effect against all bacteria. The minimum inhibitory concentration of the acetone extract was 7 mg/mL, and the minimum bactericidal concentration was 10 mg/mL, while the corresponding values for hibiscus acid were 4-7 and 7 mg/mL, respectively. The results of the crystal violet assay indicate that hibiscus acid alters membrane permeability. Hibiscus acid is a potential alternative to control multidrug-resistant bacteria. Due to its ready availability and easy extraction from H. sabdariffa, hibiscus acid is potentially useful in the food industries.

Effect of a Synbiotic Mix on Intestinal Structural Changes, and Salmonella Typhimurium and Clostridium Perfringens Colonization in Broiler Chickens.

Synbiotics can prevent gastrointestinal infections in broilers. This work studies the effect of a Synbiotic on broilers. One-day-old male broilers were divided into groups: Control; Synbiotic; Synbiotic + S. Typhimurium; Synbiotic + C. perfringens; Synbiotic + S. Typhimurium + C. perfringens; S. Typhimurium; C. perfringens; and S. Typhimurium + C. perfringens. Histopathological analysis revealed that the Synbiotic promoted longer villi, less deep crypts, and better villi-crypt ratio. Broilers treated with the Synbiotic, infected with pathogens or not, had healthier mucosa. In groups infected with pathogens, the frequency and intensity of histopathologic lesions were lessened often in groups treated with the Synbiotic. The Synbiotic group had higher lactic acid bacteria counts than the Control group on day 39, and the isolation frequency of S. Typhimurium was lower (p < 0.05) in the Synbiotic-treated groups. On day 18, mucosa, villi, villi-crypt ratio, crypt, and feed intake were influenced by Enterobacteriaceae. However, on day 39 (end of the trial), those parameters were influenced by lactic acid bacteria. The Synbiotic influenced morphological modifications in the duodenal mucosa, which in turn gave the broilers the ability to resist infections caused by S. Typhimurium and C. perfringens, by inhibiting their growth and decreasing the intensity and frequency of histopathological injuries.

Effect of Dual Modification on the Spectroscopic, Calorimetric, Viscosimetric and Morphological Characteristics of Corn Starch.

The effect of dual modification of corn starch, including hydrolysis and succinylation, were evaluated through peak viscosity (PV) analysis, differential scanning calorimetry (DSC), scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR) and Raman spectroscopy. This dual modification was shown to increase the reaction efficiency (RE) and degree substitution (DS) compared with starches that were not subjected to acid hydrolysis pretreatment with a 44% and 45% increase respectively. After acid hydrolysis pretreatment, the surface of the corn starch granules exhibited exo-erosion and whitish points due to the accumulation of succinyl groups. The peak viscosity was reduced significantly with the acid hydrolysis pretreatment (between 3 and 3.5-fold decrease), which decreased the pasting temperature and peak time to 20 °C and 100 s respectively. In addition, the dual modification of corn starch altered certain thermal properties, including a reduction in the enthalpy of gelatinization (ΔH) and a higher range of gelatinization (around 6 °C), which may effectively improve industrial applications. Modifications on the FTIR spectra indicated that the dual modification affected the starch crystallinity, while the Raman spectra revealed that the dual modification disrupted the short-range molecular order in the starch. Rearrangement and molecular destabilization of the starch components promoted their granular amphiphilic properties.

Presence of Multidrug-Resistant Shiga Toxin-Producing Escherichia coli, Enteropathogenic Escherichia coli, and Enterotoxigenic Escherichia coli on Fresh Cheeses from Local Retail Markets in Mexico.

Cheesemaking is one of the most important industries in Mexico. Among all the Mexican cheeses, fresh cheeses are the most popular and most consumed cheese in Mexico and Latin America. However, in Mexico fresh cheese is frequently made with unpasteurized milk and sold in public markets. This may increase the risk for contamination of dairy products with pathogenic bacteria. The presence of multidrug-resistant pathogenic bacteria in food is an important public health concern. Diarrheagenic Escherichia coli pathotypes (DEPs) are foodborne bacteria. This study investigated the presence of indicator bacteria and multidrug-resistant DEPs in fresh cheeses. A total of 120 fresh cheese samples were collected from public markets in the city of Pachuca, Mexico. The samples were analyzed for presence of fecal coliforms (FC), E. coli, and antibiotic resistant DEPs. FC and E. coli were analyzed using the most-probable-number technique. DEPs were identified using two multiplex PCR methods. Susceptibility to 16 antibiotics was tested for the isolated DEPs strains by the standard assay. The frequency of FC, E. coli, and DEPs in the cheese samples was 50, 40, and 19%, respectively. The identified DEPs included Shiga toxin-producing E. coli (STEC; 8%), enteropathogenic E. coli (EPEC; 6%), and enterotoxigenic E. coli (ETEC; 5%). All isolated strains exhibited resistance to at least five antibiotics. One, one, two, and three STEC strains were resistant to 14, 12, 11, and 10 antibiotics, respectively. One strain of EPEC was resistant to 11 antibiotics, three EPEC strains to 9, and one strain to 7. One, one, and two strains of ETEC were resistant to 10, 8, and 7 antibiotics, respectively. The results of the present study indicate that fresh cheeses made with unpasteurized milk could be a risk for consumers, both for native people and visitors to Mexico.

Nutritional Characterization of Prosopis laevigata Legume Tree (Mesquite) Seed Flour and the Effect of Extrusion Cooking on its Bioactive Components.

Mesquite (Prosopis laevigata) is a legume tree widely distributed in Aridoamerica. The mature fruit of this legume is a pod, which is currently underutilized and has high nutritional potential. In the present work, mesquite seed flour is described in terms of its nutritional value, as well as the effect of extrusion cooking on its bioactive components. Mesquite seed flour is rich in fiber (7.73 g/100 g) and protein (36.51 g/100 g), with valine as the only limiting amino acid. Total phenolic compound contents in raw and extruded seed flour were 6.68 and 6.46 mg of gallic acid equivalents/g (mg GAE/g), respectively. 2-2-Diphenyl-1-picrylhydrazyl (DPPH) radical scavenging capacity values in raw and extruded seed flour were 9.11 and 9.32 mg of ascorbic acid equivalent/g (mg AAE/g), respectively. The absorbance at 290 nm, as an indicator of generation of Maillard reaction product (MRP), was the same for raw and extruded samples. Apigenin was the only flavonoid found in mesquite seed flour (41.6 mg/kg) and was stable in the extrusion process. The water absorption index (WAI) and water solubility index (WSI) were changed significantly during extrusion. The expansion of mesquite seed flour extrudates was null due to the high protein and fiber content in the sample. Extrusion cooking of mesquite seed flour is a useful form of technology for the industrialization of this underutilized and nutritionally valuable legume.

Behavior of 11 Foodborne Bacteria on Whole and Cut Mangoes var. Ataulfo and Kent and Antibacterial Activities of Hibiscus sabdariffa Extracts and Chemical Sanitizers Directly onto Mangoes Contaminated with Foodborne Bacteria.

The behavior of foodborne bacteria on whole and cut mangoes and the antibacterial effect of Hibiscus sabdariffa calyx extracts and chemical sanitizers against foodborne bacteria on contaminated mangoes were investigated. Mangoes var. Ataulfo and Kent were used in the study. Mangoes were inoculated with Listeria monocytogenes, Shigella flexneri, Salmonella Typhimurium, Salmonella Typhi, Salmonella Montevideo, Escherichia coli strains (O157:H7, non-O157:H7 Shiga toxin-producing, enteropathogenic, enterotoxigenic, enteroinvasive, and enteroaggregative). The antibacterial effect of five roselle calyx extracts (water, ethanol, methanol, acetone, and ethyl acetate), sodium hypochlorite, colloidal silver, and acetic acid against foodborne bacteria were evaluated on contaminated mangoes. The dry extracts obtained with ethanol, methanol, acetone, and ethyl acetate were analyzed by nuclear magnetic resonance spectroscopy to determine solvent residues. Separately, contaminated whole mangoes were immersed in five hibiscus extracts and in sanitizers for 5 min. All foodborne bacteria attached to mangoes. After 20 days at 25 ± 2°C, all foodborne bacterial strains on whole Ataulfo mangoes had decreased by approximately 2.5 log, and on Kent mangoes by approximately 2 log; at 3 ± 2°C, they had decreased to approximately 1.9 and 1.5 log, respectively, on Ataulfo and Kent. All foodborne bacterial strains grew on cut mangoes at 25 ± 2°C; however, at 3 ± 2°C, bacterial growth was inhibited. Residual solvents were not detected in any of the dry extracts by nuclear magnetic resonance. Acetonic, ethanolic, and methanolic roselle calyx extracts caused a greater reduction in concentration (2 to 2.6 log CFU/g) of all foodborne bacteria on contaminated whole mangoes than the sodium hypochlorite, colloidal silver, and acetic acid. Dry roselle calyx extracts may be a potentially useful addition to disinfection procedures of mangoes.