Fermentation Method Research Articles

Optimizing glutamate production from microalgae extracts sourced from the Caspian Sea Basin: A cost-effective and sustainable approach with potential applications

The versatile free amino acid known as glutamate plays a key role in biological processes as a transmitter of signals between nerve cells, as well as in the food industry as a flavor enhancer. Extensive endeavors have been undertaken to produce glutamate using various methods, often relying on costly and scarce natural resources. This study aims to explore a cost-effective and abundant natural alternative for glutamate synthesis by utilizing microalgae extract sourced from the Caspian Sea basin. To achieve this goal, the submerged fermentation method was utilized. The fermented microalgae extract, inoculated with P. putida, exhibited substantially higher concentrations of glutamate compared to the uninoculated samples. Amongst the various seaweeds investigated, the aqueous Chlorella extract exhibited the highest Glutamate amount (3.1 ± 0.1 mg/g). Moreover, both the fresh and dehydrated microalgae extracts displayed a noteworthy rise in the concentration of soluble proteins during fermentation. It is worth mentioning that extracts treated with P. putida exhibited a total rise in the levels of overall phenolics and flavonoids, suggesting a promising improvement in their biologically active combinations. Furthermore, the functions of alpha-amylase and proteolytic enzymes experienced significant increments in the fermented extracts. This research highlights a promising method for generating glutamate using microalgae extract which has significant potential for the food industry, offering numerous advantages.

Effect of Solid-State Fermentation on Phytochemical and Proximate Composition of Millet Bran Meal

The majority of a fish farm's overall operating expenses involve costs related to feeds. Commercial feeds are often too expensive for fish farmers. Consequently, farmers do use agricultural by-products and locally available fish feed ingredients to improve pond productivity and minimise cost. This study was aimed at evaluating the effects of solid-state fermentation on phytochemical components and proximate composition of millet bran meal for possible incorporation in fish feed production. Millet bran was collected in three different bowls, ground to powder, and then sieved and fermented using a solid-state fermentation procedure. Each sample was fermented (wet at 10% moisture and kept in a container at ambient temperature) for 24 hours (1 day), 96 hours (4 days), and 168 hours (7 days). Afterwards, the fermented samples were sun-dried for 94 hours (4 days approximately). Quantitative phytochemical screening was carried out on the samples which were analysed for proximate composition. The results revealed that fermenting millet bran for seven days (168hrs) using solid-state fermentation method reduced the alkaloid content from 14.69±1.24 to 10.12±0.16, phytate from 5.73±1.32 to 3.25±0.73, tannins from 6.62±0.53 to 4.62±0.84, oxalate from 17.78±1.65 to 13.82±0.53. However, it increases flavonoids from 11.95±1.82 to 13.08±1.35 and phenols from 23.78±1.65 to 31.71±0.62. The study also elucidates an increase in crude protein from 9.23±0.64 to 19.77±0.53 and a reduction in crude fibre from 7.41±0.52 to 6.02±1.14. This study demonstrates that solid-state fermented millet bran meal can be incorporated as an essential part of feed production.

Enhancing quality of ruminant feed through fungal treatment: Usage of bamboo shoot residues.

In this investigation, we explore the harnessing of bamboo shoot residues (BSR) as a viable source for ruminant feed through fungal treatment, with the overarching objective of elevating feed quality and optimizing bamboo shoot utilization. The white-rot fungi (Wr.fungi), Aspergillus niger (A.niger), and its co-cultures (A.niger&Wr.fungi) were employed to ferment BSR. And the impact of different fermentation methods and culture time on the chemical composition (Crude protein Ash, neutral detergent fibre and acid detergent fibers), enzyme activity (Cellulase, Laccase, Filter paperase and Lignin peroxidase activities), and rumen digestibility in vitro were assessed. The findings reveal a nota ble 30.39% increase in crude protein in fermented BSR, accompanied by respective decreases of 13.02% and 17.31% in acid detergent fiber and neutral detergent fibre content. Enzyme activities experienced augmentation post-fermentation with A.niger&Wr.fungi. Specifically, the peak Cellulase, Laccase, and Lignin peroxidase activities for BSR with Wr.fungi treatment reached 748.4 U/g, 156.92 U/g, and 291.61 U/g, respectively, on the sixth day of fermentation. Concurrently, NH3-N concentration exhibited an upward trend with prolonged fermentation time. Total volatile fatty acids registered a decline, and the Acetate/Propionate ratio reached its nadir after 6 days of fermentation under the A.niger&Wr.fungi treatment. These outcomes furnish a theoretical foundation for the development of ruminant feeds treated via fungal co-culture.

Effect of addition of γ-poly glutamic acid on bacterial nanocellulose production under agitated culture conditions.

Bacterial nanocellulose (BNC), a natural polymer material, gained significant popularity among researchers and industry. It has great potential in areas, such as textile manufacturing, fiber-based paper, and packaging products, food industry, biomedical materials, and advanced functional bionanocomposites. The main current fermentation methods for BNC involved static culture, as the agitated culture methods had lower raw material conversion rates and resulted in non-uniform product formation. Currently, studies have shown that the production of BNC can be enhanced by incorporating specific additives into the culture medium. These additives included organic acids or polysaccharides. γ-Polyglutamic acid (γ-PGA), known for its high polymerization, excellent biodegradability, and environmental friendliness, has found extensive application in various industries including daily chemicals, medicine, food, and agriculture. In this particular study, 0.15g/L of γ-PGA was incorporated as a medium additive to cultivate BNC under agitated culture conditions of 120rpm and 30℃. The BNC production increased remarkably by 209% in the medium with 0.15g/L γ-PGA and initial pH of 5.0 compared to that in the standard medium, and BNC production increased by 7.3% in the medium with 0.06g/L γ-PGA. The addition of γ-PGA as a medium additive resulted in significant improvements in BNC production. Similarly, at initial pH levels of 4.0 and 6.0, the BNC production also increased by 39.3% and 102.3%, respectively. To assess the characteristics of the BNC products, scanning electron microscopy, Fourier transform infrared spectroscopy, and thermogravimetric analysis were used. The average diameter of BNC fibers, which was prepared from the medium adding 0.15g/L γ-PGA, was twice thicker than that of BNC fibers prepared from the control culture medium. That might be because that polyglutamic acid relieved the BNC synthesis from the shear stress from the agitation. This experiment held great significance as it explored the use of a novel medium additive, γ-PGA, to improve the production and the glucose conversion rate in BNC fermentation. And the BNC fibers became thicker, with better thermal stability, higher crystallinity, and higher degree of polymerization (DPv). These findings lay a solid foundation for future large-scale fermentation production of BNC using bioreactors.

Production of Gibberellic Acid by Aspergillus Niger: A Review

Gibberellic acid (GA3) is a plant hormone found naturally in plants and fungi. It is a white to pale-yellow solid with the chemical formula C19H22O6. Although plants naturally produce GA3, it is often produced commercially from fungi for agricultural use. The production of GA3 through fermentation methods, including submerged fermentation (SmF) and semi-solid-state fermentation (SSSF), is explored, with a focus on optimizing production and reducing costs. Additionally, the review delves into the factors influencing GA3 production, both physical and chemical parameters. It emphasizes the use of agro-industrial residues as cost-effective sources for GA3 production, promoting environmentally friendly recycling and reducing the environmental impact. Quantification methods for GA3, are discussed, highlighting the challenges and benefits associated with each method. Furthermore, the applications of GA3 in horticulture, agriculture, and the food industry are outlined, demonstrating its diverse range of effects on various plants and crops.

Engineering Implementation of the Acosta Fermentation Method to Obtain Cuban Schnapps with Reduced Concentrations of Higher Alcohols

The Acosta method involves rewiring the yeast metabolic pathway to enhance biomass production and prevent a significant increase in higher alcohols during the late stages of fermentation. This study aimed to assess fermentation conditions to achieve Cuban schnapps with reduced concentrations of higher alcohols and replicate the process on an industrial scale. To achieve this, the quality of final sugarcane molasses for fermentation by Saccharomyces cerevisiae (S. cerevisiae) yeast was evaluated. Industrial pre-fermentation and fermentation processes were successfully conducted, followed by laboratory-scale fermentation using the Acosta fermentation method to determine crucial parameters for industrial implementation. Operational parameters for fermentation were identified from the following results: 13.5 °Brix seeding, metabolic pathway inversion of S. cerevisiae at 16 h, and an air concentration of 0.1 m3/min. The resulting Cuban schnapps obtained using this method exhibited a concentration of higher alcohols of 132.5 mg/L, a value that is within the standard parameters, showing a positive impact of this fermentation method on the quality of the schnapps. Scaling up this method to an industrial level, in addition to offering higher quality products and being an economically viable alternative, also stands out for its sustainable and environmentally friendly aspect, and results in higher production of yeast biomass as a byproduct, which can be used for various purposes, such as animal feed. This method constitutes an important update to the schnapps production process as a technological improvement that respects sustainable production trends and the characteristics of the final product.

Cinnamosyn, a Cinnamoylated Synthetic-Bioinformatic Natural Product with Cytotoxic Activity.

Most biosynthetic gene clusters (BGCs) are functionally inaccessible by using fermentation methods. Bioinformatic-coupled total synthesis provides an alternative approach for accessing BGC-encoded bioactivities. To date, synthetic bioinformatic natural product (synBNP) methods have focused on lipopeptides containing simple lipids. Here we increase the bioinformatic and synthetic complexity of the synBNP approach by targeting BGCs that encode N-cinnamoyl lipids. This led to our synthesis of cinnamosyn, a 10-mer N-cinnamoyl-containing peptide that is cytotoxic to human cells.

Rare and unexplored traditional waste food processing and fermentation methods of the meitei-pangal community of Manipur: A northeastern state of India

This research examines rare and unexplored traditional waste food processing and fermentation methods. Processed waste foods as well as fermented foods represent an important segment of the most commonly consumed foodstuffs and the nutrient suppliers of the living populations across the world. Soibum, hawaijar, ngari, hentak, and yongchak are some of the most commonly consumed processed waste foods and fermented foods among the natives of Manipur. To our knowledge, no proper compilation of traditional methods of waste food processing and the fermentation processes of the meitei-pangal community of Manipur has been carried out yet. In this study, the traditional methods of processing waste foods and fermentation steps of foodstuffs commonly consumed by the Meitei pangal community of Manipur are surveyed and recorded for the first time. The results of the study reveal that six unique and diverse categories and ways of processing waste foods and the fermentation of food products locally known as Yongchak, chakring, ngari, hentak, soibum, and hawaijar were practiced by every family of the meitei-pangal community of Manipur using local stinky beans (Parkia sp.), cooked rice-based products, local fish (Puntius sp.), bamboo shoots (Bambusa sp.), and soybean products. The study will offer a new understanding of the waste food processing and fermentation processes of some of the most commonly consumed foodstuffs by the natives of the northeastern states of India, with numerous health advantages for prospective future drug discoveries and nutraceutical applications.

Improvement of nucleotide content of Cordyceps tenuipes by Schisandra chinensis: fermentation process optimization and application prospects.

Nucleotides are important components and the main indicators for judging Cordyceps quality. In this paper, the mixed fermentation process of Schisandra chinensis and Cordyceps tenuipes was systematically studied, and it was proposed that the fermentation products aqueous extract (S-ZAE) had antioxidant activity and anti-AChE ability. Herein, the results of a single factor showed that S. chinensis, yeast extract, inoculum amount, and pH had significant effects on nucleotide synthesis. The fermentation process optimization results were 3% glucose, 0.25% KH2PO4, 2.1% yeast extract, and S. chinensis 0.49% (m/v), the optimal fermentation conditions were 25℃, inoculum 5.8% (v/v), pH 3.8, 6 d. The yield of total nucleotides in the scale-up culture was 0.64 ± 0.027mg/mL, which was 10.6 times higher than before optimization. S-ZAE has good antioxidant and anti-AChE activities (IC50 0.50 ± 0.050mg/mL). This fermentation method has the advantage of industrialization, and its fermentation products have the potential to become good functional foods or natural therapeutic agents.

Bioethanol from Arthrospira platensis biomass using a combined pretreatment

With the aim to reduce the reliance on gasoline by supporting efficient bioethanol production to meet the biofuel goal of 46 % in the transportation sector by 2050, the present study proposes a combined pretreatment of microwave-assisted acid hydrolysis for bioethanol production, which was applied to commercially-produced microalgal biomass of Arthrospira platensis. The Separated Hydrolysis and Fermentation (SHF) method was applied to prevent sugar loss and produce a higher bioethanol yield. After examining the effect of acid concentrations (0, 0.1, 0.2, and 0.3 M) and hydrolysis duration (30, 60, 90, 120, and 180 min) on the fermentable sugars, it was discovered that both operation parameters had a major impact on the synthesis of monosaccharides. With a 0.3 M H2SO4 concentration and a 90-minute hydrolysis time at 100 °C, the maximum concentration of fermentable sugars of 11.60 g/L was obtained. Regarding the fermentable sugar yield, the suggested combined pretreatment (78.4 %) outperforms the literature-reported single pretreatment of acid hydrolysis (55 %), under comparable operating settings. After 96 h of anaerobic fermentation with Saccharomyces cerevisiae, the hydrolysate of the fermentable sugars produced 0.06 g ethanol/g biomass, corresponding to 0.35 g ethanol/g total carbohydrates in Arthrospira platensis.

Fermenting kale (Brassica oleracea L.) enhances its functional food properties by increasing accessibility of key phytochemicals and reducing antinutritional factors.

The properties of kale as a functional food are well established. We sought to determine how fermentation further enhances these properties. We tested different fermentation conditions: (i) spontaneous fermentation with naturally occurring bacteria, (ii) spontaneous fermentation with 2% salt, (iii) Lactococcus lactis, (iv) Lactobacillus acidophilus, (v) mixture of L. lactis and L. acidophilus, (vi) mixture of L. lactis, L. acidophilus, and Clostridium butyricum. We quantified selected bioactive components using high-performance liquid chromatography (HPLC) and antinutritional factors using a gravimetric method and spectrophotometry. We then determined (i) the antioxidant capacity of the vegetable, (ii) anti-inflammation capacity, and (iii) the surface microbiota composition by 16S sequencing. All fermentation methods imparted some benefits. However, fermentation with mixed culture of L. lactis and L. acidophilus was most effective in increasing polyphenols and sulforaphane accessibility, increasing antioxidant activity, and reducing antinutritional factors. Specifically, fermentation with L. lactis and L. acidophilus increased total polyphenols from 8.5 to 10.7 mgGAE/g (milligrams of gallium acid equivalent per gram) and sulforaphane from 960.8 to 1777 μg/g (microgram per gram) but decreased the antinutritional factors oxalate and tannin. Total oxalate was reduced by 49%, while tannin was reduced by 55%-65%. The antioxidant capacity was enhanced but not the anti-inflammation potential. Both unfermented and fermented kale protected equally against lipopolysaccharide (LPS)-induced inflammation in RAW 264.7 macrophages and prevented increases in inducible nitric oxide synthase (iNOS), tumor necrosis factor-alpha (TNF-α), interleukin-1 beta (IL-1β), and interleukin-6 messenger RNA (IL-6 mRNA) expression by 84.3%, 62%, 68%, and 85.5%, respectively. Unfermented and naturally fermented kale had high proportions of sulfur reducing Desulfubrio and Proteobacteria usually associated with inflammation. Fermenting with L. lactis and/or L. acidophilus changed the bacterial proportions, reducing the Proteobacteria while increasing the genera Lactobacilli and Lactococcus. In summary, fermentation enhances the well-known beneficial impacts of kale. Fermentation with mixed cultures of L. lactis and L. acidophilus imparts higher benefits compared to the single cultures or fermentation with native bacteria present in the vegetable.

Effect of Lactobacillus plantarum and flavourzyme on protein degradation and flavor development in grass carp during fermentation

This study examined the effect of Flavourzyme and Lactobacillus plantarum (L. plantarum) on protein degradation and flavor development during grass carp fermentation. The control groups comprised natural fermentation and fermentation with L. plantarum. Compared with the two control samples, those exposed to combined Flavourzyme and L. plantarum fermentation exhibited lower moisture content and enhanced protein hydrolysis, which accelerated the production of water-soluble taste substances (trichloroacetic acid-soluble peptides and free amino acids). The electronic tongue and electronic nose results indicated that the grass carp subjected to combined fermentation way displayed a more intense umami taste and aroma. Moreover, the sensory evaluation results confirmed that the combined fermentation method significantly improved the taste and odor attributes of fermented grass carp. In conclusion, combined fermentation with Flavourzyme and L. plantarum may effectively reduce fermentation time and enhance the flavor of fermented grass carp products.

Synthesis and Characterization of Indigofera Zollingeriana Plant-Based Ruminant Feed Using EM 4 Fermentation Method

This study aimed to produce ruminant feed pellets using Indigofera zollingeriana as the main ingredient, along with coconut pulp, rice bran, molasses, cassava, and EM 4 as additional components. The objective was to investigate the impact of optimizing animal feed pellets made from Indigofera zollingeriana and various mixed ingredients, such as rice bran, coconut pulp, cassava, molasses, and EM 4, by using the EM 4 fermentation method on the physical, mechanical, and chemical properties of the animal feed pellets. The animal feed was prepared by blending Indigofera zollingeriana, coconut pulp, rice bran, and cassava in the proportion of (55.81% : 22.1% : 14.73% : 7.365%), along with molasses and EM 4 in a 1:1 ratio. The test samples were produced by weighing, pulverizing, mixing, fermenting, drying, and molding into pellets. The findings showed that the animal feed pellets made with Indigofera zollingeriana plant concentrate had physical properties that did not meet the standard values, such as specific gravity (1.96 gr/mL), porosity (8.84%), water absorption (68.76%), maturity temperature (38ºC), and solubility in water (4.36%). However, the animal feed pellets had a brownish color and a normal smell, similar to other animal feeds. In terms of mechanical properties, the values for hardness (5.002%) and brittleness (1.53%) met the standard values for animal feed pellets. Regarding chemical properties based on proximate analysis, the animal feed contained 8.22% protein, 6.78% total fat, 26.4% crude fiber, 17.4% carbohydrates, 7.50% ash content, and 33.7% moisture content. Only the ash content met the SNI 3148-2:2017 standard. Thus, the quality of these animal feed pellets needs improvement.

Optimizing the ratio of raw materials and pH on biogas production from cow manure with banana peel waste in batch system reactors

Politeknik Negeri Jember has dairy cows TEFA which produce relatively large amounts of cow dung waste, namely 280 kg per day. The fecal waste is directly thrown into waterways, causing air pollution, namely causing an unpleasant odor. It would be interesting to conduct research on cow dung waste in TEFA of dairy cows. This research was carried out with the aim of utilizing cow manure which is waste in TEFA dairy cattle as raw material for biogas with a mixture of banana peel waste as a substrate. In this research, a batch system reactor with an anaerobic fermentation method was used. The variables used were the ratio of cow manure to banana peel waste with variations of 1:1, 1:2, 1:3, and the pH variable variations of 6, 7, and 8. The test parameter observed in the research was the volume of biogas. The experimental design used to determine optimum conditions is the Response Surface Method (RSM). The experimental design was carried out on 2 variables with 3 variations so that 9 data points were obtained. Based on the test results, it is known that the optimum conditions for the variable ratio of cow dung to banana peel waste and pH are 1:3 and the pH variation is 6, where the volume of gas produced is 177.8 ml.

Unraveling a Historical Mystery: Identification of a Lichen Dye Source in a Fifteenth Century Medieval Tapestry

As part of a long-term campaign to document, study, and conserve the Heroes tapestries from The Cloisters collection at The Metropolitan Museum of Art, organic colorant analysis of Julius Caesar (accession number 47.101.3) was performed. Analysis with liquid chromatography–quadrupole time-of-flight mass spectrometry (LC-qToF-MS) revealed the presence of several multiply chlorinated xanthones produced only by certain species of lichen. Various lichen dye sources have been documented in the literature for centuries and are classified as either ammonia fermentation method (AFM) or boiling water method (BWM) dyes based on their method of production. However, none of these known sources produce the distinctive metabolites present in the tapestry. LC-qToF-MS was also used to compare the chemical composition of the dyes in the tapestry with that of several species of crustose lichen. Lichen metabolites, including thiophanic acid and arthothelin, were definitively identified in the tapestry based on comparison with lichen xanthone standards and a reference of Lecanora sulphurata, confirming the presence of a lichen source. This finding marks the first time that lichen xanthones have been identified in a historic object and the first evidence that BWM lichen dyes may have been used prior to the eighteenth century.

A review on fermented vegetables: Microbial community and potential upgrading strategy via inoculated fermentation.

Fermentation is a traditional method utilized for vegetable preservation, with microorganisms playing a crucial role in the process. Nowadays, traditional spontaneous fermentation methods are widely employed, which excessively depend on the microorganisms attached to the surface of raw materials, resulting in great difficulties in ideal control over the fermentation process. To achieve standardized production and improve product quality, it is essential to promote inoculated fermentation. In this way, starter cultures can dominate the fermentation processes successfully. Unfortunately, inoculated fermentation has not been thoroughly studied and applied. Therefore, this paper provides a systematic review of the potential upgrading strategy of vegetable fermentation technology. First, we disclose the microbial community structures and succession rules in some typical spontaneously fermented vegetables to comprehend the microbial fermentation processes well. Then, internal and external factors affecting microorganisms are explored to provide references for the selection of fermented materials and conditions. Besides, we widely summarize the potential starter candidates with various characteristics isolated from spontaneously fermented products. Subsequently, we exhibited the inoculated fermentation strategies with those isolations. To optimize the product quality, not only lactic acid bacteria that lead the fermentation, but also yeasts that contribute to aroma formation should be combined for inoculation. The inoculation order of the starter cultures also affects the microbial fermentation. It is equally important to choose a proper processing method to guarantee the activity and convenience of starter cultures. Only in this way can we achieve the transition from traditional spontaneous fermentation to modern inoculated fermentation.

Optimization of Biohydrogen Production from Vinasse and Cow Manure Using the Response Surface Method (RSM)

The problem of greenhouse gas emissions and the energy crisis experienced by countries in the world, including Indonesia, makes it necessary to develop alternative energy. Biohydrogen from biomass waste can be the best alternative to overcome this problem because it is a clean energy and is capable of producing high energy. This research was carried out with the aim of analyzing the increase in biohydrogen production using the anaerobic fermentation method with a nanomaterial catalyst. The test material in this study was a volatile solid which was analyzed using the gravimetric method. The experimental design used to determine optimum conditions is the Response Surface Method (RSM). The variable used in this research is the ratio between the cow manure and vinasse raw material with variations of 1:1, 1:2, and 1:3. The other variables used are pH with variations of 6.7 and 8. Based on the test results, it is known that the optimum conditions for the variable ratio of cow feces to banana peel waste and pH are 1:3 (the variable ratio of cow feces to banana peel waste) and variations pH 6 (variable pH) with a total volatile solid of 100 mg/L. The addition of nickel-based nanomaterial also has a significant effect on the volatile solid content, where the volatile solid content without the addition of nanomaterial is 42.62 g/L, while with the addition of the volatile solid nanomaterial produced is 100.92 g/L.

Synthesis and Characterization of Ruminant Feed Based on Palm Kernel Cake Using EM4 Fermentation Method

The purpose of this study was to determine the effect of the addition of cassava as an adhesive and the use of palm kernel meal as a concentrate and the addition of other ingredients on the physical, mechanical and chemical properties of food ingredients in the form of pellets. The animal feed was made by mixing palm kernel meal, tofu dregs, rice bran, and cassava with a percentage of (68,5 : 15,75 : 5,25 : 10,5)% and mixing molasses and EM 4 in a ration 1 : 1. The test samples were made by going through the stages of weighing, chopping, mixing, fermentation, drying, and molding into pellets. The results showed that the animal feed mixture had a specific gravity of 1.70 gr/mL, porosity of 29.05%, water absorption of 72.62%, pellet hardness of 4.85%, and brittleness with 4.92%. Animal feed pellets have a brownish color and a normal smell like the smell of animal feed pellets in general. The fermentation process was carried out for 8 days until it reached a maturity temperature of 38.44°C. Based on the proximate analysis, it was found that the animal feed contained 10.50% protein, 2.30% total fat, 22.80% crude fiber, 28.50% carbohydrate, 3.00% ash content and 32.90% moisture content. This animal feed pellet with palm kernel meal concentrate and cassava adhesive can be used as an alternative to cattle feed as an energy source feed, because it has a protein content of less than 20%.

Developing a High-Umami, Low-Salt Soy Sauce through Accelerated Moromi Fermentation with Corynebacterium and Lactiplantibacillus Strains.

The traditional fermentation process of soy sauce employs a hyperhaline model and has a long fermentation period. A hyperhaline model can improve fermentation speed, but easily leads to the contamination of miscellaneous bacteria and fermentation failure. In this study, after the conventional koji and moromi fermentation, the fermentation broth was pasteurized and diluted, and then inoculated with three selected microorganisms including Corynebacterium glutamicum, Corynebacterium ammoniagenes, and Lactiplantibacillus plantarum for secondary fermentation. During this ten-day fermentation, the pH, free amino acids, organic acids, nucleotide acids, fatty acids, and volatile compounds were analyzed. The fermentation group inoculated with C. glutamicum accumulated the high content of amino acid nitrogen of 0.92 g/100 mL and glutamic acid of 509.4 mg/100 mL. The C. ammoniagenes group and L. plantarum group were rich in nucleotide and organic acid, respectively. The fermentation group inoculated with three microorganisms exhibited the best sensory attributes, showing the potential to develop a suitable fermentation method. The brewing speed of the proposed process in this study was faster than that of the traditional method, and the umami substances could be significantly accumulated in this low-salt fermented model (7% w/v NaCl). This study provides a reference for the low-salt and rapid fermentation of seasoning.

Novel microbial fermentation for the preparation of iron-chelating scallop skirts peptides-its profile, identification, and possible binding mode

Iron chelating peptides have been widely utilized as iron supplements due to their excellent absorption capacity, However, the high cost and cumbersome manufacturing process of these peptides significantly limit their industrial application. In this study, fermentation was used for the first time to prepare iron chelating peptides. Bacillus altitudinis 3*1–3 was selected as the most suitable strain from 50 strains. The hydrolysates of fermented scallop skirts showed excellent iron-chelating capacity (9.39 mg/g). Aspartic acid, glutamic acid, and histidine are crucial for the binding of peptides to ferrous ions. The heptapeptide (FEDPEFE) forms six binding bonds with ferrous irons. Compared with ferrous sulfate, peptide-ferrous chelate showed more stability in salt solution and simulated gastrointestinal juice (p < 0.05). Furthermore, the fermentation method could save >50% of the cost compared with the enzymatic method. The results can provide a theoretical basis for the preparation of ferrous-chelated peptides using the fermentation method.