Antifungal Activity Enhancement of Cell-Free Streptomyces griseus Extract Obtained by Fermentation with Magnetic Manganese Ferrite Nanoparticles.

The present study aims to obtain manganese ferrite nanoparticles functionalized with chitosan (C-MNP) or ethylenediamine (E-MNP) by coprecipitation and polyol one-step methods, characterize their interaction with S. griseus demonstrating cell immobilization, and evaluate the antimicrobial activity of the free cell extracts obtained from immobilized S. griseus fermentation in the presence of different concentrations of MNP. The adsorption isotherms were analyzed mathematically using Langmuir and Freundlich models. The highest coefficient of determination (R2) for the S. griseus cell adsorption isotherm with C-MNP was observed with a linear function of the Langmuir model. The adsorption isotherm of S. griseus cells with E-MNP was better fitted to the Freundlich model. Cell immobilization by adsorption on magnetic nanoparticles was demonstrated in both cases. Different concentrations of C-MNP and E-MNP were used in fermentations to prepare cell-free extracts with antifungal activity. The best results were obtained with E-MNP, with a 91.5% inhibition of radial fungal growth. Magnetic nanoparticles offer potential applications in different fields and easy biomass separation.

Identification, Antioxidant Capacity, and Matrix Metallopeptidase 9 (MMP-9) In Silico Inhibition of Haloarchaeal Carotenoids from Natronococcus sp. and Halorubrum tebenquichense.

Natural pigments from haloarchaea are of great interest; bacterioruberin is the major pigment, it shows higher antioxidant power when compared with ß-carotene. However, characterization of bacterioruberin and its isomers along with its antioxidant and the matrix metallopeptidase 9 (MMP-9) inhibition activities in extracts from Natronoccoccus sp. TC6 and Halorubrum tebenquichense SU10 was not previously described, being the aim of this work. The carotenoids profile was performed by UV-Vis spectrophotometry, thin-layer chromatography, nuclear magnetic resonance spectroscopy, and high-resolution mass spectrometry (UPLC-ESI-MS/MS). Antioxidant capacity was determined for DPPH, ABTS, and FRAP. In addition, MMP-9 inhibition was studied using docking simulations. The carotenoid profile of studied strains was composed of bacterioruberin, some derivatives like mono, bis, and tris anhydrobacterioruberin, and also some bacterioruberin cis isomers. The carotenoid pools showed antioxidant capacity for DPPH > ABTS > FRAP; Natronococcus sp. TC6 carotenoid pool was better for ABTS and DPPH, while Halorubrum tebenquichense SU10 carotenoid pool was better for FRAP. Additionally, docking and molecular dynamics suggest that bacterioruberin inhibits MMP-9 through hydrophobic interactions near the catalytic site. Bacterioruberin shows the higher binding energy of -8.3 (kcal/mol). The carotenoids profile of both strains was elucidated, their antioxidant activity and singular participation of each carotenoid on MMP-9 in silico inhibition were evaluated.

Trichoderma as a biological control agent: mechanisms of action, benefits for crops and development of formulations.

Currently, the food and economic losses generated by the attack of phytopathogens on the agricultural sector constitute a severe problem. Conventional crop protection techniques based on the application of synthetic pesticides to combat these undesirable microorganisms have also begun to represent an inconvenience since the excessive use of these substances is associated with contamination problems and severe damage to the health of farmers, consumers, and communities surrounding the fields, as well as the generation of resistance by the phytopathogens to be combated. Using biocontrol agents such as Trichoderma to mitigate the attack of phytopathogens represents an alternative to synthetic pesticides, safe for health and the environment. This work explains the mechanisms of action through which Trichoderma exerts biological control, some of the beneficial aspects that it confers to the development of crops through its symbiotic interaction with plants, and the bioremedial effects that it presents in fields contaminated by synthetic pesticides. Also, detail the production of spore-based biopesticides through fermentation processes and formulation development.

Production of a Fungal Punicalagin-Degrading Enzyme by Solid-State Fermentation: Studies of Purification and Characterization.

The present work describes the purification of an enzyme capable of degrading punicalagin. The enzyme was produced by Aspergillus niger GH1 by solid-state fermentation, and the enzyme production was induced by using ellagitannins as the sole carbon source. The purification steps included the concentration by lyophilization, desalting, anionic exchange, and gel filtration chromatography. The enzyme kinetic constants were calculated by using punicalagin, methyl gallate, and sugar beet arabinans. The molecular mass of the protein was estimated by SDS-PAGE. The identified bands were excised and digested using trypsin, and the peptides were submitted to HPLC-MS/MS analysis. The docking analysis was conducted, and a 3D model was created. The purification fold increases 75 times compared with the cell-free extract. The obtained Km values were 0.053 mM, 0.53% and 6.66 mM for punicalagin, sugar beet arabinans and methyl gallate, respectively. The optimal pH and temperature for the reaction were 5 and 40 °C, respectively. The SDS-PAGE and native PAGE analysis revealed the presence of two bands identified as α-l-arabinofuranosidase. Both enzymes were capable of degrading punicalagin and releasing ellagic acid.

Bioactive protein hydrolysates obtained from amaranth by fermentation with lactic acid bacteria and Bacillus species.

Protein hydrolysates are a promising source of bioactive peptides. One strategy by which they can be obtained is fermentation. This method uses the proteolytic system of microorganisms to hydrolyze the parental protein. Fermentation is a little-explored method for obtaining protein hydrolysates from amaranth. Different strains of lactic acid bacteria (LAB) and Bacillus species isolated from goat milk, broccoli, aguamiel, and amaranth flour were used in this work. First, the total protein degradation (%TPD) of amaranth demonstrated by the strains was determined. The results ranged from 0 to 95.95%, the strains that produced a higher %TPD were selected. These strains were identified by molecular biology and were found to correspond to the genera Enterococcus, Lactobacillus, Bacillus, and Leuconostoc. Fermentation was carried out with amaranth flour and the selected strains. After this process, water/salt extracts (WSE) containing the released protein hydrolysates were obtained from amaranth doughs. The peptide concentration was measured by the OPA method. The antioxidant, antihypertensive and antimicrobial activity of the WSE was evaluated. In the FRAP test, the best WSE was LR9 with a concentration of 1.99 µMTE/L ± 0.07. In ABTS, 18C6 obtained the highest concentration with 19.18 µMTE/L ± 0.96. In the DPPH test, there was no significant difference. In terms of antihypertensive activity, inhibition percentages ranging from 0 to 80.65% were obtained. Some WSE were found to have antimicrobial properties against Salmonella enterica and Listeria monocytogenes. Fermentation of amaranth with LAB and Bacillus spp. allowed the release of protein hydrolysates with antioxidant, antihypertensive, and antimicrobial activity.

Gradually supply of isoamyl alcohol increases the isoamyl acetate production in solid-state fermentation.

Nowadays, isoamyl acetate production is carried out by chemical synthesis with a recent interest in developing biological producing processes, mainly based on microorganisms in submerged fermentation. This work assayed producing isoamyl acetate through solid-state fermentation (SSF), feeding the precursor in the gas phase. Polyurethane foam functioned as the inert support to contain 20 ml of a solution of molasses (10% w/v, pH 5.0). The yeast Pichia fermentans was inoculated at 3 × 107 cells per gram of initial dry weight. The airstream to supply oxygen also served to supply the precursor. Slow supply was obtained using an isoamyl alcohol solution of 5 g l-1 in the bubbling columns and an air stream of 50 ml min-1. For fast supply, fermentations were aerated using 10 g l-1 and 100 ml min-1 for isoamyl alcohol solution and air stream, respectively. It demonstrated the feasibility of isoamyl acetate production in SSF. Moreover, the slow supply of the precursor increased isoamyl acetate production up to 390 mg l-1, which is 12.5 times higher than that obtained without precursor (32 mg l-1). On the other hand, fast supply caused an evident inhibition of the growth and production capacity of the yeast.

Medicinal plants used by rural communities in the arid zone of Viesca and Parras Coahuila in northeast Mexico.

This study is the first record of medicinal plants in the southwest of the Coahuila state, an arid zone where extreme dry conditions prevail. One hundred twenty-two residents (in sixteen communities) were interviewed. The residents were questioned with a questionnaire-guided ethnomedical survey protocol about the various plants used. Seventy-seven species of medicinal plants belonging to 36 botanical families were cited. The highest use-value (UV) was calculated for Lippia graveolens Kunth (0.30); Aloe vera (L.) Burm.f. (0.20); Eucalyptus abdita Brooker & Hopper, Chamaemelum nobile (L.) All. (0.16); Mentha spicata L. (0.15) and Salvia officinalis L. (0.10). Informant consensus factor (ICF) about usages of medicinal plants ranges from 0.41 to 0.80; the highest level of agreement was determined between the informants and Respiratory System Diseases (0.80). The highest fidelity level (FL) values (100%) were identified in Flourensia cernua DC., Artisia ludoviciana Nutt., and Parthenium incanum Kunth to Gastro-intestinal System Diseases; Eucalyptus abdita Brooker & Hopper, Bougainvillea berberidifolia Heimerl, and Lippia graveolens Kunth to Respiratory System Diseases (RSD) and Cyclolepis genistoides D.Don and Ephedra antisyphilitica Berland. ex C.A.Mey. to Obstetrics, Gynecology and Urinary tract Diseases. These last two medicinal plant species ("palo azul" and "pitoreal") used by the rural communities in Viesca in the treatment of urinary tract infections and kidney stones have not been reported previously. These findings can provide new research directions for further phytochemical studies. The present study revealed that the residents are rich in ethno-medicinal knowledge and actively use medicinal plants to treat various diseases. New phytochemical and pharmacological research are needed to confirm the therapeutic potential and safety of the identified plants.

Biocatalyst developed with recovered iron-rich minerals enhances the biotransformation of SARS-CoV-2 antiviral drugs in anaerobic bioreactors.

The biotransformation of the SARS-CoV-2 antiviral drugs, ribavirin and tenofovir, was studied in methanogenic bioreactors. The role of iron-rich minerals, recovered from a metallurgic effluent, on the biotransformation process was also assessed. Enrichment of anaerobic sludge with recovered minerals promoted superior removal efficiency for both antivirals (97.4 % and 94.7 % for ribavirin and tenofovir, respectively) as compared to the control bioreactor lacking minerals, which achieved 58.5 % and 37.9 % removal for the same drugs, respectively. Further analysis conducted by liquid chromatography coupled to mass spectroscopy revealed several metabolites derived from the biotransformation of both antivirals. Interestingly, tracer analysis with 13CH4 revealed that anaerobic methane oxidation coupled to Fe(III) reduction occurred in the enriched bioreactor, which was reflected in a lower content of methane in the biogas produced from this system, as compared to the control bioreactor. This treatment proposal is suitable within the circular economy concept, in which recovered metals from an industrial wastewater are applied in bioreactors to create a biocatalyst for promoting the biotransformation of emerging pollutants. This strategy may be appropriate for the anaerobic treatment of wastewaters originated from hospitals, as well as from the pharmaceutical and chemical sectors.

Fungal Proteins from Sargassum spp. Using Solid-State Fermentation as a Green Bioprocess Strategy.

The development of green technologies and bioprocesses such as solid-state fermentation (SSF) is important for the processing of macroalgae biomass and to reduce the negative effect of Sargassum spp. on marine ecosystems, as well as the production of compounds with high added value such as fungal proteins. In the present study, Sargassum spp. biomass was subjected to hydrothermal pretreatments at different operating temperatures (150, 170, and 190 °C) and pressures (3.75, 6.91, and 11.54 bar) for 50 min, obtaining a glucan-rich substrate (17.99, 23.86, and 25.38 g/100 g d.w., respectively). The results indicate that Sargassum pretreated at a pretreatment temperature of 170 °C was suitable for fungal growth. SSF was performed in packed-bed bioreactors, obtaining the highest protein content at 96 h (6.6%) and the lowest content at 72 h (4.6%). In contrast, it was observed that the production of fungal proteins is related to the concentration of sugars. Furthermore, fermentation results in a reduction in antinutritional elements, such as heavy metals (As, Cd, Pb, Hg, and Sn), and there is a decrease in ash content during fermentation kinetics. Finally, this work shows that Aspergillus oryzae can assimilate nutrients found in the pretreated Sargassum spp. to produce fungal proteins as a strategy for the food industry.

Successive Fermentation of Aguamiel and Molasses by Aspergillus oryzae and Saccharomyces cerevisiae to Obtain High Purity Fructooligosaccharides.

Fructooligosaccharides (FOS) are usually synthesized with pure enzymes using highly concentrated sucrose solutions. In this work, low-cost aguamiel and molasses were explored as sucrose alternatives to produce FOS, via whole-cell fermentation, with an Aspergillus oryzae DIA-MF strain. FOS production process was optimized through a central composite experimental design, with two independent variables: initial sucrose concentration in a medium composed of aguamiel and molasses (AgMe), and inoculum concentration. The optimized process-165 g/L initial sucrose in AgMe (adjusted with concentrated molasses) and 1 × 107 spores/mL inoculum concentration-resulted in an FOS production of 119 ± 12 g/L and a yield of 0.64 ± 0.05 g FOS/g GFi. Among the FOSs produced were kestose, nystose, 1-fructofuranosyl-nystose, and potentially a novel trisaccharide produced by this strain. To reduce the content of mono- and disaccharides in the mixture, run a successive fermentation was run with two Saccharomyces cerevisiae strains. Fermentations run with S. cerevisiae S227 improved FOS purity in the mixture from 39 ± 3% to 61.0 ± 0.6% (w/w) after 16 h of fermentation. This study showed that agro-industrial wastes such as molasses with aguamiel are excellent alternatives as substrate sources for the production of prebiotic FOS, resulting in a lower-cost process.

Recent trends and technological development in plasma as an emerging and promising technology for food biosystems.

The rising need for wholesome, fresh, safe and "minimally-processed" foods has led to pioneering research activities in the emerging non-thermal technology of food processing. Cold plasma is such an innovative and promising technology that offers several potential applications in the food industry. It uses the highly reactive, energetic and charged gas molecules and species to decontaminate the food and package surfaces and preserve the foods without causing thermal damage to the nutritional and quality attributes of food. Cold plasma technology showed promising results about the inactivation of pathogens in the food industry without affecting the food quality. It is highly effective for surface decontamination of fruits and vegetables, but extensive research is required before its commercial utilization. Recent patents are focused on the applications of cold plasma in food processing and preservation. However, further studies are strongly needed to scale up this technology for future commercialization and understand plasma physics for getting better results and expand the applications and benefits. This review summarizes the emerging trends of cold plasma along with its recent applications in the food industry to extend shelf life and improve the quality of food. It also gives an overview of plasma generation and principles including mechanism of action. Further, the patents based on cold plasma technology have also been highlighted comprehensively for the first time.

Prebiotic effect, bioactive compounds and antioxidant capacity of melon peel (Cucumis melo L. inodorus) flour subjected to in vitro gastrointestinal digestion and human faecal fermentation.

Melon peels are by-products derived from food processing industries, representing potential sources of new ingredients in particular dietary fibre and phenolic compounds, which in synergy could exert beneficial effects on human health. The objective of this study was to evaluate the accessibility of bioactive compounds from melon peels throughout gastrointestinal digestion and evaluate their prebiotic effect when submitted to in vitro human faecal fermentation. Melon peels flour obtained from solid fraction showed an increase in antioxidant capacity at the gastric and intestinal phase, which was corroborated by the total phenolic content (126.91%) increase and the identified individual phenolics (tyrosol, luteolin-6-glycoside, chlorogenic and caffeic acids). Also, melon peels flour positively impacted the gut microbiota diversity, showing a similar ratio of Firmicutes/Bacteroidetes compared to the positive control (FOS) and promoted the production of short-chain fatty acids, mainly acetate > propionate > butyrate. Thus, these findings demonstrate that melon peels have antioxidant and prebiotic potential attributed to the phenolic compounds and the production of beneficial fatty acids, which could improve human gut health.

Co-microencapsulation: a promising multi-approach technique for enhancement of functional properties.

Co-microencapsulation is a growing technique in the food industry because it is a technique that, under the same fundamentals of microencapsulation, allows the generation of microcapsules with a longer shelf life, using a smaller number of encapsulating materials and a smaller amount of active compounds, while having a greater beneficial activity. This responds to consumer demand for higher quality foods that limit the use of ingredients with low nutritional content and provide beneficial health effects, such as probiotics, prebiotics, vitamins, fatty acids, and compounds with antioxidant activity. The combination of two or more active compounds that achieve a synergy between them and between the encapsulating materials offers an advantage over the well-known microencapsulation. Among the main active compounds used in this process are probiotics, prebiotics, fatty acids, and polyphenols, the main combination being that of probiotics with one of the other active compounds that enhances their benefits. The present review discusses the advantages and disadvantages of the different encapsulating materials and techniques used to obtain co-microencapsulants, where the main result is a higher survival of probiotics, higher stability of the active compounds and a more controlled release, which can lead to the generation of new foods, food supplements, or therapeutic foods for the treatment of common ailments.

Growth kinetics and quantification of carbohydrate, protein, lipids, and chlorophyll of Spirulina platensis under aqueous conditions using different carbon and nitrogen sources.

This study evaluated different carbon and nitrogen sources on the growth and production of carbohydrates, protein, lipids, and chlorophyll of Spirulina platensis LEB-52 through an easy successive methodology under aqueous conditions. Spirulina platensis was cultivated at 120 rpm and light intensity of 156 µmol m-2 s-1 in a 500 mL Erlenmeyer flask with a working volume of 250 mL, using Zarrouk's medium. The biomass, carbohydrate, and protein production together with the specific growth rate did not show a significant difference between NaHCO3 and Na2CO3. The salts of urea and ammonium are not an alternative nitrogen sources of low cost for Spirulina platensis cultivation. From the experimental results obtained in this study, a successful estimate of carbohydrate, protein, lipids, and chlorophyll content inside Spirulina platensis was achieved without use advanced analytical techniques, allowing saves resources and time. This method can be extrapolated to other microorganisms and cultivation regimens.

Sucrose Hydrolysis in a Continuous Packed-Bed Reactor with Auto-immobilise Aspergillus niger Biocatalyst Obtained by Solid-State Fermentation.

Invertase from Aspergillus niger C28B25 was produced by solid-state fermentation (SSF). Fermented solids were used directly as a biocatalyst for batch and continuous hydrolysis of sucrose in a packed-bed reactor under different operational conditions with various temperatures, sucrose concentrations, and feed flow rates. The SSF allowed obtaining a biocatalyst with an invertase activity of 82.2 U/g db. The biocatalyst maintained its activity in the range of 40 to 70 °C for at least 70 h of continuous operation. In a 20-mL packed bed reactor, the highest hydrolysis rate (12.3 g/g db h) was obtained at 40 °C with 2 M sucrose. Continuous hydrolysis in 20-mL and 200-mL reactors at 60 °C led to sucrose hydrolysis above 60% (8.5 residence times) and above 55% (4.5 residence times), respectively. The auto-immobilised biocatalyst produced by SSF without recovery, purification, and immobilisation stages offers an economical alternative for developing accessible biocatalysts that can be applied in batch or continuous sucrose hydrolysis processes. This study shows the potential of biocatalyst production by SSF for other enzymatic systems.

Antioxidant Dietary Fiber Sourced from Agroindustrial Byproducts and Its Applications.

Agroindustrial activities generate various residues or byproducts which are inefficiently utilized, impacting the environment and increasing production costs. These byproducts contain significant amounts of bioactive compounds, including dietary fiber with associated phenolic compounds, known as antioxidant dietary fiber (ADF). Phenolic compounds are related to the prevention of diseases related to oxidative stress, such as neurodegenerative and cardiovascular diseases. The mechanism of ADF depends on its chemical structure and the interactions between the dietary fiber and associated phenolic compounds. This work describes ADF, the main byproducts considered sources of ADF, its mechanisms of action, and its potential use in the formulation of foods destined for human consumption. ADF responds to the demand for low-cost, functional ingredients with great health benefits. A higher intake of antioxidant dietary fiber contributes to reducing the risk of diseases such as type II diabetes, colon cancer, obesity, and kidney stones, and has bile-acid retention-excretion, gastrointestinal laxative, hypoglycemic, hypocholesterolemic, prebiotic, and cardioprotective effects. ADF is a functional, sustainable, and profitable ingredient with different applications in agroindustry; its use can improve the technofunctional and nutritional properties of food, helping to close the cycle following the premise of the circular economy.

Procyanidins: From Agro-Industrial Waste to Food as Bioactive Molecules.

Procyanidins are an important group of bioactive molecules known for their benefits to human health. These compounds are promising in the treatment of chronic metabolic diseases such as cancer, diabetes, and cardiovascular disease, as they prevent cell damage related to oxidative stress. It is necessary to study effective extraction methods for the recovery of these components. In this review, advances in the recovery of procyanidins from agro-industrial wastes are presented, which are obtained through ultrasound-assisted extraction, microwave-assisted extraction, supercritical fluid extraction, pressurized fluid extraction and subcritical water extraction. Current trends focus on the extraction of procyanidins from seeds, peels, pomaces, leaves and bark in agro-industrial wastes, which are extracted by ultrasound. Some techniques have been coupled with environmentally friendly techniques. There are few studies focused on the extraction and evaluation of biological activities of procyanidins. The identification and quantification of these compounds are the result of the study of the polyphenolic profile of plant sources. Antioxidant, antibiotic, and anti-inflammatory activity are presented as the biological properties of greatest interest. Agro-industrial wastes can be an economical and easily accessible source for the extraction of procyanidins.

Mexican Oregano (Lippia graveolens Kunth) as Source of Bioactive Compounds: A Review.

Lippia graveolens is a traditional crop and a rich source of bioactive compounds with various properties (e.g., antioxidant, anti-inflammatory, antifungal, UV defense, anti-glycemic, and cytotoxicity) that is primarily cultivated for essential oil recovery. The isolated bioactive compounds could be useful as additives in the functional food, nutraceuticals, cosmetics, and pharmaceutical industries. Carvacrol, thymol, ß-caryophyllene, and p-cymene are terpene compounds contained in oregano essential oil (OEO); flavonoids such as quercetin O-hexoside, pinocembrin, and galangin are flavonoids found in oregano extracts. Furthermore, thermoresistant compounds that remain in the plant matrix following a thermal process can be priced in terms of the circular economy. By using better and more selective extraction conditions, the bioactive compounds present in Mexican oregano can be studied as potential inhibitors of COVID-19. Also, research on extraction technologies should continue to ensure a higher quality of bioactive compounds while preventing an undesired chemical shift (e.g., hydrolysis). The oregano fractions can be used in the food, health, and agricultural industries.

Valorisation of food agro-industrial by-products: From the past to the present and perspectives.

Food agro-industrial by-products mainly include peels, seeds, stems, bagasse, kernels, and husk, derived during food processing. Due to their overproduction and the lack of sustainable management, such by-products have been conventionally rejected and wasted in landfills, being the principal strategy for their treatment, but nowadays, this strategy has been associated with several environmental, social and economic issues. Hence, we focused on the use of different consolidated biotechnological processes and methodologies as suitable strategies for food by-products management and valorisation, highlighting them as potential bioresources because they still gather high compositional and nutritional value, owing to their richness in functional and bioactive molecules with human health benefits. Food by-products could be utilised for the development of new food ingredients or products for human consumption, promoting their integral valorisation and reincorporation to the food supply chain within the circular bioeconomy concept, creating revenue streams, business and job opportunities. In this review, the main goal was to provide a general overview of the food agro-industrial by-products utilised throughout the years, improving global sustainability and human nutrition, emphasising the importance of biowaste valorisation as well as the methodologies employed for the recovery of value-added molecules.

Influence of culture conditions on ellagitannase expression and fungal ellagitannin degradation.

The role and mechanism of elagitannase is misunderstood because it exhibited different activities due to the low purity or complexity of substrates, and there is no available information about the biochemical, physicochemical and molecular characteristics of the enzyme. This study was aimed to obtain enzymatic extracts by Aspergillus niger GH1 in solid-state fermentation, using dextrose and ellagitannins as inducers of ellagitannase. Protein and bioinformatic analysis were performed to identify the protein sequence expressed in terms of culture conditions. The presence of ellagitannins increased ellagitannase activity 1143-fold compared to dextrose. The higher ellagitannase activity was found at 18 h of culture (1143.30 U g-1PE). Three groups of proteins were identified in both cultures: ß-glucosidase, phospholipase C, and triacylglycerol lipase. However, only phospholipase C was overexpressed with ellagitannins as inducers, showing the most spontaneous reaction with punicalagin (ΔG -8.56). These results suggest that phospholipase could be involved in ellagitannins biosynthesis.