Optimization Of Fermentation Conditions Research Articles

Optimization of Fermentation and Biocontrol Efficacy of Bacillus atrophaeus XHG-1-3m2

Biological control plays an increasingly important role in various aspects of modern agriculture and forestry. Identifying biocontrol strains with commercial potential for effective disease management is currently a focal point in biological control research. In this study, Bacillus atrophaeus XHG-1-3m2, a strain with significant biocontrol potential against Wilsonomyces carpophilus causing shot hole disease in wild apricots, was developed. The study determined the antibacterial activity of the fermentation broth, the optimal fermentation medium composition and conditions, and explored its effectiveness in controlling Wilsonomyces carpophilus. The optimal fermentation medium for strain XHG-1-3m2 comprises 12.5 g/L yeast extract, 12.5 g/L soy peptone, 10.0 g/L sodium chloride, 1 g/L ammonium chloride, 1 g/L potassium dihydrogen phosphate, 1 g/L disodium hydrogen phosphate, and 0.5 g/L magnesium sulfate heptahydrate. With an initial pH of 7.0, a liquid volume of 40%, an inoculum volume of 3%, and shaking incubation at 28 °C for 24 h, the viable cell count reached 14 × 109 CFU/mL. In vitro and in vivo tests on leaves revealed that the fermentation broth and the biocontrol biofertilizer derived from this strain inhibited the leaf lesions caused by Wilsonomyces carpophilus on wild apricots, achieving inhibition rates of 94.62% and 82.46%, respectively.

A Novel Biosynthetic Strategy for Ginsenoside Ro: Construction of a Metabolically Engineered Saccharomyces cerevisiae Strain Using a Newly Identified UGAT Gene from Panax ginseng as the Key Enzyme Gene and Optimization of Fermentation Conditions

Ginsenoside Ro, as one of the few oleanane-type ginsenosides, is well known for its unique molecular structure and biological activities. Currently, research on the biosynthesis of ginsenoside Ro is still in its early stages. Therefore, the establishment of a new ginsenoside Ro cell factory is of great significance for the in-depth development and utilization of genes related to ginsenoside Ro synthesis, as well as for the exploration of pathways to obtain ginsenoside Ro. In this study, we cloned endogenous constitutive promoters, terminators, and other genetic elements from S. cerevisiae BY4741. These elements were then sequentially assembled with the uridine diphosphate glucuronic acid transferase gene identified in our previously study (PgUGAT252645) and several other reported key enzyme genes, to construct DNA fragments used for integration into the genome of S. cerevisiae BY4741. By sequentially transferring these DNA fragments into chemically competent cells of engineering strains and conducting screening and target product detection, we successfully constructed an engineered S. cerevisiae strain (BY-Ro) for ginsenoside Ro biosynthesis using S. cerevisiae BY4741 as the host cell. Strain BY-Ro produced 253.32 μg/L of ginsenoside Ro under optimal fermentation conditions. According to subsequent measurements and calculations, this equates to 0.033 mg/g DCW, corresponding to approximately 31% of the ginsenoside Ro content found in plant samples. This study not only included a deeper investigation into the function of PgUGAT252645 but also provides a novel engineering platform for ginsenoside Ro biosynthesis.

Innovative Lactic Acid Production Techniques Driving Advances in Silage Fermentation

Lactic acid (LA) plays a crucial role in the silage process, which occurs through LA fermentation. Consequently, there is a strong correlation between lactic acid production and the efficiency of the silage. However, traditional methods face challenges like long fermentation times, low acid production, and unstable quality, limiting agricultural preservation. This paper aims to explore innovations in lactic acid production technologies and show how these technologies have driven the development of silage fermentation for agricultural conservation. First, the important role of LA in agricultural preservation and the limitations of traditional silage techniques are presented. Next, advancements in LA production methods are thoroughly examined, covering the selection of microbial strains and the substitution of fermentation substrates. Following this, new technologies for silage fermentation are explored, drawing from innovations in LA production. These include the selection of LA strains, optimization of fermentation conditions, and improvements in fermentation techniques. These innovations have proven effective in increasing LA production, improving feed quality, extending shelf life, and providing new solutions to enhance agricultural production and sustainability.

Lactic acid bacteria sequential fermentation improves viable counts and quality of fermented apple juice via generating two logarithmic phases

This study investigated the impact of lactic acid bacteria (LAB) sequential fermentation on viable counts and apple juice quality. The optimal fermentation conditions were obtained by a step-by-step optimization process, including pH 4.5, temperature 37 °C, the second inoculation time 16 h, total fermentation time 40 h and fermentation sequence (first 21,805 + 21,828, second 20,241). Under the optimal conditions, sequential fermentation allowed LAB to experience two logarithmic phases, increasing viable counts to 1.38 × 108 CFU/mL, exceeding simultaneous fermentation for 24 h and 40 h by 4.10 × 107 CFU/mL and 5.40 × 107 CFU/mL, respectively. This process enhanced sugar utilization, yielding more lactic acid and polyphenols. Furthermore, sequential fermentation improved DPPH (71.71 %) and ABTS (84.79 %) scavenging rates, and enriched volatile compounds, particularly beta-Damascenone, potentially contributing to floral and richer apple flavor. Sequential fermentation also achieved optimal sensory acceptability. This study proposes a novel strategy for high-density LAB fermentation to produce high-quality apple juice.

Characterization of newly isolated Bacillus cereus D3 Co-producing α-amylase and protease and its application in food raw materials

Bacillus cereus, which effectively secretes various extracellular enzymes, has been widely used in the food, feed, and fermentation industries. One strain co-producing α-amylase and protease was newly isolated from Daqu and identified as B. cereus D3. It was shown that the production of α-amylase and protease co-produced by B. cereus D3 reached 13.89 ± 0.07 and 2468.45 ± 38.96 U/mL through optimization of fermentation conditions (nutrients (g/L): 20 of glucose, 20 of urea, 0.7 of MnCl2; incubation conditions: 24 h of incubation, initial medium pH of 7.0, temperature of 37 °C, 8% inoculum size, and 30% working volume). Moreover, the enzymatic genetic co-expression exhibited a similar pattern to the changes in enzymatic activities (growth-phase-dependent pattern). The two enzymes performed excellent thermal stability and were stable over wide pH ranges of 6.0–11.0 and 2.0–8.0, respectively. Finally, the hydrolysis degrees of raw materials including rice, sorghum, corn, and soybeans by α-amylase from B. cereus D3 reached 66.59 ± 4.21, 57.99 ± 4.39, 57.44 ± 4.67, and 38.01% ± 1.73%, respectively, producing glucose and maltose as the main products. The hydrolysis degrees of proteinous materials including mackerel heads and soybeans by protease from B. cereus D3 were 39.93 ± 1.99 and 30.44% ± 1.39%. SDS-PAGE analysis displayed extensive breakdown of macromolecular proteins, forming peptides of varied sizes. This is a systematic study on the co-production of α-amylase and protease by B. cereus, which is crucial to widen the understanding of this species co-producing multi-enzymes and explore its potential application in the food fermentation industry.

Optimization of fermentation conditions for Bacillus velezensis TCS001 and evaluation of its growth promotion and disease prevention effects on strawberries

Bacillus velezensis TCS001 is a novel biocontrol bacterium with broad-spectrum antifungal activity and plant growth-promoting effects, holding great potential for development in agricultural production. This study optimized the fermentation conditions for B. velezensis TCS001 through single-factor experiments combined with response surface methodology, and developed a formulation for TCS001 suspension concentrate (TCS001-SC). The efficacy of TCS001-SC to promote the growth of strawberries and to prevent and control strawberry anthracnose was evaluated. The optimal liquid fermentation condition for TCS001 was determined to be 2.89 % soluble peanut cake powder, 3.0 % glucose, 3.0 % soluble starch, 0.002 % FePO4, 0.006 % KCl, 0.6 % NaCl, 0.05 % MgCl2·6H2O, 0.3 % K2HPO4, 0.15 % KH2PO4, 0.05 % CaCO3, 0.005 % MnSO4, a working volume of 31 % (77.5 mL/250 mL), a rotation speed of 173 r/min, a cultivation temperature of 28°C, an inoculum volume of 1.0 %, and a pH of 7.0. The 15 L fermenter upscale culture achieved a spore count of 9.46 × 109 CFU/mL, which was 2.01 times the spore count of 4.7 × 109 CFU/mL before optimization, and a preliminary TCS001-SC was developed with the fermented broth as the main component. Agar plate confrontation tests showed that TCS001 had antifungal activity against five types of anthracnose fungi, with inhibition rates ranging from 70.3 % to 87.2 %. TCS001-SC could promote the growth of strawberries and induce a rapid defense enzyme response in their leaves, enhancing the plant's resistance to pathogens. After treatment, individual strawberry plants showed significant increases in the number of leaves, fresh weight of stems and leaves, root fresh weight, leaf area, plant height, and the content of POD, SOD, CAT enzymes, GA, IAA, and ABA compared to the control.Additionally, it shows good prevention and control effects against strawberry anthracnose, with a control efficacy of 60.45% after five spray treatments at a concentration of 2 × 107 CFU/mL, which is not significantly different from the efficacy of commercial microbial agents such as Bacillus subtilis wettable powder, subsequent field trials will be conducted to determine its potential as a microbial pesticide. This study provides important support for the future industrial production and application of the strain TCS001.

Preparation and flavor characteristics of plant-based meat flavoring by mixed fermentation of multiple strains

In this study, plant-based meat flavoring was prepared by mixed fermentation and thermal reaction. Based on the changes of amino acid nitrogen, reducing sugar, and total acid during the fermentation process and combined with sensory evaluation, the optimal fermentation conditions were determined as 4 % total inoculation amount of Monascus purpureus, Actinomucor elegans, and Bacillus subtilis with an inoculation ratio of 1:1:1, and 36 h of fermentation time. The odor characterization of meat flavoring was identified by solid-phase microextraction–gas chromatography–mass spectrometry (SPME–GC–MS), aroma extract dilution analysis (AEDA), quantitative measurements, odor activity value (OAV) and aroma recombination and omission experiments. 64 volatile compounds and 28 odorants were identified. The compounds with FD ≥ 27 were precisely quantified by five-point standard calibration curve and OAVs were calculated, and those with OAV ≥ 1 were subjected to aroma recombination and omission experiments. Finally, furfuryl mercaptan, difurfuryl disulfide, 4-methyl-5-ethylthiazole, 1-octanal, and 2-acetylthiophene were determined to be the key aroma-active compounds. These compounds have been recognized as key aroma-active compounds or detected in other meats or meat flavorings. In this study, we prepared plant-based meat flavoring through mixed fermentation, and provide new ideas for the development of plant-based thermal reaction meat flavoring process.

Optimization of Liquid Fermentation of Acanthopanax senticosus Leaves and Its Non-Targeted Metabolomics Analysis

To enhance the nutritional value of Acanthopanax senticosus leaves (AL), a fermentation process was conducted using a probiotic Bacillus mixture, and the changes in chemical constituents and biological activities before and after fermentation were compared. A response surface methodology was employed to optimize the liquid fermentation conditions of AL based on their influence on polyphenol content. Non-targeted metabolomics analysis was performed using LC-MS/MS to reveal the differing profiles of compounds before and after fermentation. The results indicated that Bacillus subtilis LK and Bacillus amyloliquefaciens M2 significantly influenced polyphenol content during fermentation. The optimal fermentation conditions were determined to be a fermentation time of 54 h, a temperature of 39.6 °C, and an inoculum size of 2.5% (v/v). In comparison to unfermented AL, the total polyphenol and flavonoid contents, as well as the free radical scavenging capacities measured by DPPH and ABTS assays, and the activities of β-glucosidase and endo-glucanase, were significantly increased. The non-targeted metabolomics analysis identified 1348 metabolites, of which 829 were classified as differential metabolites. A correlation analysis between the differential metabolites of polyphenols, flavonoids, and antioxidant activity revealed that 13 differential metabolites were positively correlated with antioxidant activity. Kyoto encyclopedia of genes and genomes (KEGG) enrichment analysis of the differential metabolites identified 82 pathways, with two of the top 25 metabolic pathways related to flavonoids. This study explores the potential for enhancing the active ingredients and biological effects of AL through probiotic fermentation using Bacillus strains.

Optimization, purification and characterization of laccase from a new endophytic Trichoderma harzianum AUMC14897 isolated from Opuntia ficus-indica and its applications in dye decolorization and wastewater treatment.

Hazardous synthetic dye wastes have become a growing threat to the environment and public health. Fungal enzymes are eco-friendly, compatible and cost-effective approachfor diversity of applications. Therefore, this study aimed to screen, optimize fermentation conditions, and characterize laccase from fungal endophyte with elucidating its ability to decolorize several wastewater dyes. A new fungal endophyte capable of laccase-producing was firstly isolated from cladodes of Opuntia ficus-indica and identified as T. harzianum AUMC14897 using ITS-rRNA sequencing analysis. Furthermore, the response surface methodology (RSM) was utilized to optimize several fermentation parameters that increase laccase production. The isolated laccase was purified to 13.79-fold. GFC, SDS-PAGE revealed laccase molecular weight at 72kDa and zymogram analysis elucidated a single band without any isozymes. The peak activity of the pure laccase was detected at 50°C, pH 4.5, with thermal stability up to 50°C and half life span for 4h even after 24h retained 30% of its activity. The Km and Vmax values were 0.1mM, 22.22µmol/min and activation energy (Ea) equal to 5.71kcal/mol. Furthermore, the purified laccase effectively decolorized various synthetic and real wastewater dyes. Subsequently, the new endophytic strain produces high laccase activity that possesses a unique characteristic, it could be an appealing candidate for both environmental and industrial applications.

Investigation into optimizing fermentation processes to enhance uric acid degradation by probiotics

To enhance the activity of Lactiplantibacillus plantarum FS4722 (L. plantarum FS4722) in reducing uric acid, this study optimized the culture medium components and fermentation conditions using response surface methodology. The results indicated that the optimal culture medium comprised glucose at 25.61g/L, yeast extract powder (YEP) at 26.86g/L, and nucleoside addition at 0.48g/L. The optimal fermentation conditions were: a fermentation time of 10h, an initial pH of 6.5, a fermentation temperature of 33 °C, and an inoculum size of 1.0%. Under these conditions, the nucleoside degradation ability of L. plantarum FS4722 increased by 41.9 times, enhancing its potential applications in reducing uric acid and developing anti-gout foods, health supplements, and pharmaceuticals.

Production-optimized fermentation of antifungal compounds by bacillus velezensis LZN01 and transcriptome analysis.

Fusarium wilt is one of the major constraints on global watermelon production, and Fusarium oxysporum f. sp. niveum (Fon) is the causative agent of Fusarium wilt in watermelon and results in severe yield and quality losses worldwide. The enhancement of antifungal activity from antagonistic bacteria against Fon is highly practical for managing Fusarium wilt in watermelon. The aim of this study was to maximize the antifungal activity of Bacillus velezensis LZN01 by optimizing fermentation conditions and analysing its regulatory mechanism via transcriptome sequencing. The culture and fermentation conditions for strain LZN01 were optimized by single-factor and response surface experiments. The optimum culture conditions for this strain were as follows: the addition of D-fructose at 35 g/L and NH4Cl at 5 g/L in LB medium, pH 7, and incubation at 30°C for 72 h. The fungal inhibition rate for strain LZN01 reached 71.1%. The improvement of inhibition rate for strain LZN01 in optimization fermentation was supported by transcriptomic analysis; a total of 491 genes were upregulated, while 736 genes were downregulated. Transcriptome analysis revealed that some differentially expressed genes involved in carbon and nitrogen metabolism, oxidation-reduction, fatty acid and secondary metabolism; This optimization process could potentially lead to significant alterations in the production levels and types of antimicrobial compounds by the strain. Metabolomics and UPLC/Q-Exactive Orbitrap MS analysis revealed that the production yields of antimicrobial compounds, such as surfactin, fengycin, shikimic acid, and myriocin, increased or were detected in the cell-free supernatant (CFS) after the fermentation optimization process. Our results indicate that fermentation optimization enhances the antifungal activity of the LZN01 strain by influencing the expression of genes responsible for the synthesis of antimicrobial compounds.

Optimization of Fermentation Conditions of Cordyceps militaris and In Silico Analysis of Antifungal Property of Cordycepin Against Plant Pathogens.

Cordyceps militaris, a medicinal fungus, has gained considerable attention owing to its potential health benefits, notably the production of bioactive compounds such as cordycepin. Cordycepin possesses significant antifungal, antibacterial, and antiviral properties. The present study focused on optimizing the fermentation conditions for C.militaris to boost the production of mycelia and cordycepin, alongside investigating its antifungal properties using in silico and in vitro approaches. The optimal conditions, yielding the highest cordycepin and mycelial biomass, were a temperature of 20°C and a pH range of 4-6, with glucose and sucrose as carbon sources and yeast extract and casein hydrolysate as nitrogen sources. Under these conditions, cordycepin production peaked at low pH (600-1000 mg/L) and with carbon and maltose (400-500 mg/L). The low temperature favored cordycepin production (400 mg/L), whereas casein hydrolysate as a nitrogen source boosted cordycepin yield (600 mg/L). The docking analysis indicated that cordycepin had the highest binding affinity for the tubulin beta chain 2 (-10.4 kcal/mol) compared to the fungicide tebuconazole (-7.9 kcal/mol for both targets). The in silico results were corroborated by in vitro studies, where the mycelial extract of C.militaris inhibited approximately 75% of fungal growth at a concentration of 6000 ppm. These findings suggest that optimizing fermentation conditions significantly enhances cordycepin production, and cordycepin shows antifungal solid activity, making it a promising agent for biocontrol in agriculture.

Evaluation of high-value bioproducts production by marine endophytic fungus Arthrinium sp. FAKSA 10 under solid state fermentation using agro-industrial wastes

BackgroundTo address public health challenges, there is increasing interest in bioactive metabolites from unconventional sources for targeted cancer and viral treatments with minimal side effects. Endophytic fungi are promising for these therapies. This study focused on maximizing bioactive agent yields from these fungi using a low-cost medium and optimized fermentation system. ResultsForty-three endophytic fungi isolated from Sinularia polydactyla were cultivated on wheat bran medium and evaluated for bioactive metabolites under solid-state fermentation. Strain FAKSA 10, identified as Arthrinium sp. FAKSA 10, exhibited the highest levels of pharmaceutical metabolites, including L-glutaminase, L-methioninase, L-arginase, L-asparaginase, L-tyrosinase, L-lysine α-oxidase, and ribonuclease, with a 79.12% hepatitis C virus knockdown rate. This strain produced 46 metabolites with anticancer, antioxidant, antiviral, and cytotoxic properties, including major compounds like hexadecanoic acid methyl ester; hexadecanoic acid ethyl ester; 9, 12-octadecadienoic acid (Z, Z), methyl ester; 9-octadecenoic acid (Z)-, methyl ester, and 11, 14-eicosadienoic acid, methyl ester. A cost effective strategy using 11 agro-industrial residues was applied, following by optimization of the solid-state fermentation system. This optimization increased enzyme yields and enhanced antiviral and antioxidant activities. The optimal conditions for solid-state fermentation were a 10 d incubation, 1 mm particle size, 60% initial moisture, 28°C temperature, and 2 × 107 CFU/mL inoculum size. ConclusionsThis study exploited Arthrinium sp. FAKSA 10 metabolites as natural pharmaceuticals against cancer and viral diseases, highlighting their significant antioxidant properties. Among various residues, oil cakes emerged as an effective and cost-efficient medium, capable of significantly enhancing the production of valuable bioactive metabolites.

Functional insights into microbial communities of Korean traditional rice wine (makgeolli) during fermentation

Makgeolli, a traditional Korean rice wine, produced by fermenting glutinous rice using a nuruk containing various microbes that can facilitate saccharification and alcoholic fermentation. The microbial communities in makgeolli determine its quality by metabolizing raw materials into physiologically active substances, such as volatile acids, ethanol, and amino acids. However, the microbial metabolic pathways associated with physicochemical properties remain poorly understood. Therefore, this study applied shotgun metagenomic sequencing to investigate the microbial communities of two makgeolli types, produced using Jinju gokja and Sansung nuruk as starters, during fermentation. Microbial structures differed depending on the starter type (nuruk), with Firmicutes and Proteobacteria dominating in the Jinju and Sansung makgeolli, respectively. Initially, the sugar content increased, displaying high level of alpha-glucosidase coding gene. Thereafter, the microbial genes encoding lactate dehydrogenase and alcohol dehydrogenase increased on day 3 of fermentation. Furthermore, lactic acid bacteria, such as Pediococcus acidilactici and Leuconostoc lactis, increased on day 3 of fermentation and were negatively correlated with pH. However, Leuconostoc sp. showed a positive correlation with acetic acid, an indicator of abnormal fermentation. These findings reveal interaction between makgeolli quality and different microbial strains related with various metabolic functions, providing insights for enhancing quality and optimizing fermentation conditions.

Optimization of exopolysaccharide production from the novel Enterococcus species, using statistical design of experiment

The Exopolysaccharide (EPS) producing novel strains of Enterococcus previously isolated from the vaginal source of pregnant women were selected based on ropy structure formation. The two selected strains, E.villorum SB-2 and E.rivorum S22-3, were found to be producing 2.87 g/l and 3.14 g/l EPS, respectively, in the minimal media (M17 media) after 24-hour fermentation under anaerobic condition. Both the strains have probiotic properties and have the potential to be used for industrial applications. The production media and fermentation conditions were optimized to enhance the EPS production using the one-factor method, Placket-Burman factorial designing and Central composite design (CCD) of Response surface methodology (RSM). The most relevant factors affecting the EPS yield were sucrose, yeast extract and pH for E.villorum SB2 and sucrose, yeast extract and magnesium sulfate for the E.rivorum S22-3 as determined by Placket-Burman design, whose concentrations were further optimized using CCD. The optimized fermentation conditions gave the total EPS of 9.76 g/l (4 times the initial production) from E.villorum SB-2 and 7.74 g/l (2.5 times the initial production) from E.rivorum S22-3, respectively, after 36-hour incubation at 37 °C. These optimization studies might be helpful during scale-up process for the industrial scale production of these exopolysaccharide.

Study of Avian Colibacillosis and Antimicrobial Resistance in Escherichia coli from Chickens (Gallus domesticus) in Maiduguri, Borno State, Nigeria

Bioethanol is a renewable, colorless, less toxic, and readily biodegradable form of fuel from biological sources; that can be used for heat, electricity, and fuel. In this research study, an alternative feedstock known as microalgae was used. Bioethanol was produced from microalgae using enzymatic hydrolysis. The microalgae was pretreated with acid and alkaline. Hydrolysis was carried out by Aspergillus niger and Saccharomyces cerevisiae was used for fermentation. The concentration of the Bioethanol produced was determined using acid Potassium Dichromate. After hydrolysis, the reducing sugar concentration was determined using Dinitrosalicylic acid (DNS) colorimetric method. Results showed that there was significant difference at p<0.05 in the yields of the reducing sugar produced between acid and alkaline pretreated samples after microbial hydrolysis. Microbial hydrolysis of alkaline pretreated samples was higher in yield. Also, the results showed that the highest bioethanol yield of 0.142ml/l was obtained after alkaline pretreated hydrolysates were fermented with Saccharomyces cerevisiae at 40°C and pH of 6.0. The highest bioethanol yield of 0.116ml/l was obtained from the acid pretreated hydrolysates at 35°C and pH of 5.5. The volatile compounds produced by alkaline pre-treated samples using Gas Chromatography Mass Spectroscopy (GCMS) shows that Ethanol and Di-n-decylsulfone were the highest volatile compounds with peak areas of 30.70% and 41.87% respectively while 2-hydroxy-1-(hydroxymethyl) ethyl ester (linolenic acid) was found to be least volatile compound with peak area of 3.34%.Tthe volatile compounds produced by acid pre-treated samples shows that 2-ethyl-2-methyltridecanol was the highest volatile compound with peak area of 23.00% while Heptacosane was found to be the least volatile compound with peak area of 1.90%. Therefore bioethanol production using alkaline pretreated samples produced a large quantity of bioethanol and may be a preferred method. This study concluded that Microalgae is a suitable substrate for bioethanol production and hydrolyzing with Aspergillus niger and optimization of fermentation conditions at pH 6.0 and 40oC yielded higher bioethanol concentration.

Optimization of fermentation conditions and analysis of the changes in flavor compounds for lemon vinegar

The flavor composition is an important index to evaluate the quality of fruit vinegar, including volatile and non-volatile components. The flavor quality of fruit vinegar is related to fermentation technology. This study analyzed the acetic acid fermentation conditions and the changes in the flavor composition of lemon vinegar. After optimization, the pH, alcohol content, and inoculum were 3.0, 6%, and 10%. The statistical analysis showed significant changes in flavor components during the whole fermentation. After acetic acid fermentation, the highest organic acid changed from citric acid to acetic acid. The content of amino acids showed a decreasing trend, mainly used for the growth and metabolism of microorganisms and the precursor of aroma compounds. Terpenoids were the main aroma compounds before the fermentation, while the main aroma compounds were esters after the fermentation. Linalool, the characteristic aroma compound in lemon, was well preserved. Isoamyl acetate was the main aroma compound during the fermentation. Almost all the flavor compounds had significant changes during the lemon vinegar fermentation. This study helps to understand the changes in flavor compounds during lemon vinegar brewing and lays the foundation for further improving the quality of lemon vinegar.

Third-Generation L-Lactic Acid Biorefinery Approaches: Exploring the Viability of Macroalgae Detritus

AbstractRising concerns over fossil fuel depletion and plastic pollution have driven research into biodegradable alternatives, such as polylactic acid (PLA). Microbial fermentation is preferred for lactic acid production due to its ability to yield enantiomerically pure lactic acid, which is essential for PLA synthesis, unlike the racemic mixture from chemical synthesis. However, commercial lactic acid production using first-generation feedstocks faces challenges related to cost and sustainability. Macroalgae offer a promising alternative with their rapid growth rates and carbon capture capabilities. This review explores recent technological advancements in macroalgae physicochemical characterization, optimization of fermentation conditions, and innovative pretreatment methods to enhance sugar conversion rates for L-LA production. It also covers downstream processes for L-LA recovery, presenting a complete macroalgal biorefinery system. Environmental impacts and economic prospects are assessed through exergy and techno-economic analyses. By valorizing macroalgae detritus, this study underscores its potential to support a sustainable biorefinery industry, addressing economic feasibility and environmental impact.

Optimization of fermentation conditions, physicochemical profile and sensory quality analysis of seedless wampee wine

The aims of the present stud were to optimize fermentation parameters of seedless wampee wine using response surface methodology (RSM) and evaluate the changes in flavor metabolites during fermentation. Seedless wampee wine of optimal sensory quality was produced using an inoculum concentration of 0.6%, initial sugar levels of 200 g/L, a fermentation temperature of 22 °C, and a fermentation period of 9 days. Then the flavor compound profiles (amino acids, organic acids and volatile aroma compounds) of seedless wampee wine during the fermentation under optimal conditions were analyzed using high performance liquid chromatography (HPLC) and gas chromatography–mass spectrometr (GC-MS). The main fermented phase of fermentation resulted in fluctuations in both total amino acids and organic acids, with stabilization occurring later on. A total of 54 volatile components, including esters, alcohols, terpenes, and acids, were putatively identified. Terpenes were the primary drivers of the flavor characteristics of seedless wampee. The rise of esters and decline of terpenes have the potential to significantly alter the flavor of wine during fermentation. These results would contribute to the further development of seedless wampee wine.Graphical

Bio-process optimization for developing a turmeric (Curcuma longa Linn.) beverage fermented with functional lactic acid starter cultures

Turmeric, scientifically known as Curcuma longa, is a herbaceous plant characterized by its rhizomatous nature with remarkable chemical composition and biologically active compounds. Lactic acid bacteria (LAB) have been observed to break down complex polyphenols into simpler, more bioactive compounds through fermentation. The success of the fermentation process relies on various factors to achieve the desired end product. This study's main goal was to assess the feasibility of using turmeric as a fermentable substrate for LAB, with the intention of creating a non-dairy fermented beverage. The investigation delved into the impact of several fermentation parameters, namely Fermentation Temperature, pH (Lemon juice concentration), Inoculum concentration, and Substrate concentration (Turmeric concentration), on the phytochemical and antioxidant properties of the lactic acid-fermented turmeric beverage (FTB). Statistical analysis revealed that a quadratic polynomial model could effectively illustrate how these fermentation parameters influenced the beverage's phytochemical and antioxidant qualities. Visualization through response surface plots revealed that these independent variables significantly influenced the beverage's total phenolic content, total flavonoid content, and antioxidant properties. Optimal fermentation conditions were identified to yield the highest levels of phenolic, flavonoid, and antioxidant content. These conditions included a Fermentation Temperature of 37.45 °C, a pH of 5.62, an Inoculum concentration of 5.12%v/v, and a Substrate (turmeric) concentration of 2.28%w/v. Under these precise conditions, experimental results closely aligned with predicted values for total phenolic content (57.46mg/100 ml), total flavonoid content (51.48mg/100 ml), and total antioxidant activity (72.24%). The overall acceptability of the fermented turmeric beverage reached a high 98.10%. Notably, the FTB exhibited significantly improved attributes such as astringency, flavor, taste, and overall acceptability when compared to the non-fermented turmeric beverage (NFTB), with statistical significance (P < 0.05).