Acid Fermentation Research Articles

Production of benzoic acid as a natural compound in fermented skim milk using commercial cheese starter

In this study, we investigated the production of natural benzoic acid (BA) in skim milk fermentation by 5 kinds of commercial cheese starters. Five kinds of starter were inoculated into 10% reconstituted skim milk, and then the culture was incubated at 2-h intervals for 10 h at 30, 35, and 40°C. In fermentation by MW 046 N+LH 13, the starter for making raclette, BA was highly detected after 8 h at 30 and 35°C. In fermentation by LH 13, the starter for making berg, BA steadily increased and was highly detected at 40°C. In fermentation by TCC-3+TCC-4, the starter for making Caciocavallo and mozzarella, BA was detected after 2 h at 40°C. Also, BA was detected after 4 and 8 h at 35 and 30°C, respectively. In fermentation by Flora-Danica, the starter for making Gouda, BA was increased until 6 h and decreased after 6 h at all temperatures. Among the 5 kinds of fermentation, the level of BA was the highest in fermentation by Flora-Danica at 6 h at 35°C, at 14.55 mg/kg.

Research on the influence of anaerobic stabilization of various dairy sewage sludge on biodegradation of polycyclic aromatic hydrocarbons PAHs with the use of effective microorganisms

Sewage sludge was taken from a dairy WWTP belonging to Mlekovita Cooperative in Wysokie Mazowieckie. There were excess sludge, flotation sludge and a mixture of excess and flotation sludge from pre-treatment of dairy sewage.The initial content of 16 PAHs in excess sludge before fermentation was approximately 689µg·kg−1 in dry mass, whereas in post-flotation sludge (which constituted around 30% of raw sludge) it was approximately 95µg·kg−1 in dry mass. A mixture of excess and flotation sludge had the content of 497,7µg·kg−1 in dry mass. Through comparison of particular hydrocarbons content in raw sewage sludge to the total PAHs content, it was shown that tricyclic compounds, which constituted 46,3% of the PAHs sum (excess sludge), and tetracyclic compounds, which constituted 60,0% of the PAHs sum (flotation sludge), were the dominating fractions.In the sludge subjected to fermentation in reactors with mixed sludge and surplus activated sludge, the general trend of the course of changes in concentrations of PAHs was similar. Both in the sludge inoculated with EM and in that not inoculated with EM, a significant increase in the total PAHs contents was observed in the first fermentation phase (acidic fermentation) after 7 days of the process. Addition of EM into the sludge did not prevent the PAHs release, and therefore higher concentrations of PAHs sum were recorded during the hydrolysis stage than in sludge before fermentation. A decrease in the sum of PAHs was observed after 2 weeks of fermentation in relation to the quantity observed after 1 week of fermentation (except from post-flotation sludge). In the following weeks, there was further decrease in the concentration of the 16 PAHs sum in all sludge types. However, in sludge without EM inoculation, it was lower than in sludge with EM inoculation. The loss of the majority of tested hydrocarbons was reported in the final phase of fermentation.

Anti-erythema and anti-edema activities of lactic acid bacteria extracts in mice

We examined the anti-inflammatory activities of 10 lactic acid bacteria extracts, obtained by lysozyme treatment. Among ferments of the 10 species, Bifidobacterium lactis showed the highest anti-erythema (73.4%) and anti-edema (67.1%) effects. When comparing the anti-inflammatory activities of fermented broth and lactic acid bacteria in fermentation broth, the anti-erythema effect (70.4%) of 37.5 μg B. lactis hydrolysate, hydrolyzed enzymatically with 2.0 mg/mL lysozyme, was superior to that of the supernatant (68.5%). The anti-edema effect (74.2%) of 50 μg B. lactis hydrolysate, hydrolyzed enzymatically with 2.0 mg/mL lysozyme, was superior to that of the supernatant (68.5%). These results suggest that B. lactis hydrolysate may be useful as a source of anti-inflammatory agents for dermal applications.

Analisis Kadar Asam Asetat Dalam Media Limbah Fermentasi Biji Kakao Akibat Penambahan Konsentrasi Acetobacter Aceti Dan Waktu Inkubasi

This study aims to determine the effect of Acetobacteraceti concentration and incubation time on levels of acetic acid in the vinegar fermentation of cocoa beans waste media. This study uses a completely randomized design (CRD) arranged as factorial, consisting of two factors and repeated three times. The frst factor is the concentration of Acetobacteraceti which consists of three levels, namely Acetobacteraceti starter concentration of 10% (A1), 13% (A2) and 16% (A3). While the second factor is the time of incubation for 6 days (W1), 8 days (W2) and 10 days (W3). Results of analysis of variance showed that the concentration of Acetobacteraceti and incubation time affect the concentration of acetic acid in the vinegar fermentation of cocoa beans waste media. While Duncan’s test results showed the treatment inoculation 13% starter Acetobacteraceti with 6 days of incubation time signifcantly different from the other treatments with maximum acetic acid content is 4,02%. So that these results meet the standards of vinegar.

Thermophilic Enterococcus faecium QU 50 enabled open repeated batch fermentation for l-lactic acid production from mixed sugars without carbon catabolite repression

Thermophilic lactic acid bacterium enabled homo-l-lactic acid fermentation from hexose/pentose without carbon catabolite repression, and open repeated production by immobilization.

Screening for Direct Production of Lactic Acid from Rice Starch Waste by Geobacillus stearothermophilus

Lactic acid recently became an important chemical where it is widely used in many industries such as food, cosmetic, chemical and pharmaceutical industry. The present study focuses on the screening for lactic acid production from rice starch waste using a thermophilic amylolytic bacterium, Geobacillus stearothermophilus . There is no information available on direct fermentation of lactic acid from rice starch waste using G. stearothermophilus . The effects of different parameters such as temperature, pH, incubation time, agitation speed, concentration of nitrogen and carbon sources on the lactic acid production were assessed. The highest concentration of lactic acid produced was 5.65 ± 0.07 g/L at operating conditions of 60°C, pH 5.5, 48 h, 200 rpm of agitation speed with 5% concentrations of both carbon and nitrogen source. The findings indicated that rice starch waste can be successfully converted to lactic acid by G. stearothermophilus .

Enhanced hydrogen production of Enterobacter aerogenes mutated by nuclear irradiation

Nuclear irradiation was used for the first time to generate efficient mutants of hydrogen-producing bacteria Enterobacter aerogenes, which were screened with larger colour circles of more fermentative acid by-products. E. aerogenes cells were mutated by nuclear irradiation of 60Co γ-rays. The screened E. aerogenes ZJU1 mutant with larger colour circles enhanced the hydrogenase activity from 89.8 of the wild strain to 157.4mLH2/(gDWh). The hereditary stability of the E. aerogenes ZJU1 mutant was certified after over ten generations of cultivation. The hydrogen yield of 301mLH2/gglucose with the mutant was higher by 81.8% than that of 166mL/gglucose with the wild strain. The peak hydrogen production rate of 27.2mL/(L·h) with the mutant was higher by 40.9% compared with that of 19.3mL/(L·h) with the wild strain. The mutant produced more acetate and butyrate but less ethanol compared with the wild strain during hydrogen fermentation.

Storage characteristics, nutritive value, and fermentation characteristics of large, round bales of alfalfa–mixed grass forage wrapped with different layers of stretch film

ABSTRACT Baled silage has become a popular form of forage conservation; however, many practical management questions have not been investigated thoroughly. Our objectives were to evaluate the number of polyethylene wrapping layers and the presence (OB) or absence (SUN) of an O 2 -limiting barrier within the wrap on the storage characteristics, nutritive value, and silage fermentation characteristics of alfalfa–mixed grass round-bale silages. Thirty-six 1.2 × 1.2-m large, round bales of a mixed sward composed predominantly of alfalfa ( Medicago sativa L.; 82 ± 3.8% alfalfa, DM basis) were packaged at 59.8 ± 3.2% DM and wrapped the same day with 4, 5, or 6 layers of the 2 polyethylene films (OB or SUN). Bales were sampled after 127 d at 0 to 0.15-m (SURFACE) and 0.15 to 0.61-m (CORE) depths. Generally, plastic type and number of wrapping layers had minimal effect on nutritive value and silage fermentation characteristics. However, greater concentrations of total fermentation acids, lactic acid, and NH 3 -N were found within the SURFACE compared with CORE layer ( P ≤ 0.03), but the titratable acidity (mean = 15.4 mEq/kg of DM; P = 0.27) and final pH (mean = 5.70; P = 0.23) did not differ. Although yeast and mold counts at the SURFACE layer often were nondetectable ( 10 cfu/g), elevated counts were most frequently associated with SUN. An O 2 -limiting barrier may improve anaerobic integrity at the surface layer of baled silages, but the potential to reduce polyethylene usage may be limited by the risk of internal physical puncture by coarse alfalfa stems.

Improved lactic acid productivity by simultaneous recovery during fermentation using resin exchanger

Lactic acid is a versatile organic acid that can be used in various applications. One of the promising applications of lactic acid is in bioplastic industry. Lactic acid is used as the monomer building block in polylactic acid synthesis. Unlike the existing applications in food and pharmaceutical industries in which lactic acid is used as the additive, it becomes the major raw material in polylactic acid production. This, therefore, raises the demand of lactic acid and eventually increases the market price. In order to expedite the bioplastic industry, cost competitiveness to the existing plastic is a big concern. The cost effectiveness and process robustness are the key success factors in bioplastic industry. Currently, lactic acid is produced via bacterial fermentation using the lime-based process. After fermentation, lactic acid was recovered from the fermentation broth by various techniques including solvent extraction, reactive distillation, ion exchanger, and electrodialysis. To achieve low production cost, not only high fermentation rate is necessary, effective recovery process is also required. In this study, we attempted simultaneous recovery of lactic acid coupled with fermentation to drive the productivity and long-term operation in continuous culture. Anion exchange resin, Amberlite IRA-400, was selected for recovering lactic acid from the bacterial culture. The preliminary results in batch adsorption showed that among other resins studied, Amberlite IRA-400 provided the best separation efficiency. Further study on fixed bed adsorption and simultaneous fermentation and lactic acid recovery using this resin were conducted and the results will be discussed in this presentation.

Effects of Process Variables on Fed-Batch Production of Propionic Acid

Plackett–Burman design in 12 treatments was used to evaluate the impact of 11 process variables on microbial production of propionic acid in fed-batch fermentation. Fermentation process took place in 3 L fermentor using basal medium and sugarcane molasses as a carbon source. The amounts of produced propionic acid were measured with an HPLC system. Statistical analysis of the results showed that while temperature was the most effective factor; all process variables had significant impact on the production of propionic acid. The highest concentration of propionic acid obtained was 6.66 ± 0.32 g/L. According to coefficient factor the most suitable condition of fermentation is combination of 30C, pH = 6.5, 45 g/l sugarcane molasses, addition of 10 g/l yeast extract, 96 h fermentation, using a mixture of P. freudenreichii and L. acidophilus with inoculum volume of 5% (v/v), and intermittent feeding of milk at a rate of 0.03 l/h. Practical Applications Prevalence of overweight and obesity has been increasing in recent decades and it has incited food producers to develop products that can enhance satiety signals. Since propionic acid has satiety properties (by simulating the secretion of intestinal peptide YY, an appetite suppressant, and delaying gastric emptying) and P. freudenreichii and L. acidophilus have healthy properties (simulating growth of Bifidobacterium, boosting the immune system, increasing the absorption of iron and calcium) as probiotic bacteria, it could be expected to achieve a dairy fermented product (by using milk as a carbon source), which may potentially provide beneficial health effects and could possibly be used for the commercial production of a functional beverage to help induce satiety. Production of propionic acid in food and beverage may lead to prolonged shelf life because of ability of acid to inhibit microbial growth. In addition to nutritional enrichment and possible satiety effect, considering the antifungal properties of propionic acid, produced dairy product in this research has a natural preservative with no necessary to use any chemical preservatives, such as sorbate.

Fermentation of lignocellulosic sugars to acetic acid by Moorella thermoacetica.

A systematic study of bioconversion of lignocellulosic sugars to acetic acid by Moorella thermoacetica (strain ATCC 39073) was conducted. Four different water-soluble fractions (hydrolysates) obtained after steam pretreatment of lignocellulosic biomass were selected and fermented to acetic acid in batch fermentations. M. thermoacetica can effectively ferment xylose and glucose in hydrolysates from wheat straw, forest residues, switchgrass, and sugarcane straw to acetic acid. Xylose and glucose were completely utilized, with xylose being consumed first. M. thermoacetica consumed up to 62% of arabinose, 49% galactose and 66% of mannose within 72h of fermentation in the mixture of lignocellulosic sugars. The highest acetic acid yield was obtained from sugarcane straw hydrolysate, with 71% of theoretical yield based on total sugars (17g/L acetic acid from 24g/L total sugars). The lowest acetic acid yield was observed in forest residues hydrolysate, with 39% of theoretical yield based on total sugars (18g/L acetic acid from 49g/L total sugars). Process derived compounds from steam explosion pretreatment, including 5-hydroxymethylfurfural (0.4g/L), furfural (0.1g/L) and total phenolics (3g/L), did not inhibit microbial growth and acetic acid production yield. This research identified two major factors that adversely affected acetic acid yield in all hydrolysates, especially in forest residues: (i) glucose to xylose ratio and (ii) incomplete consumption of arabinose, galactose and mannose. For efficient bioconversion of lignocellulosic sugars to acetic acid, it is imperative to have an appropriate balance of sugars in a hydrolysate. Hence, the choice of lignocellulosic biomass and steam pretreatment design are fundamental steps for the industrial application of this process.

The stakiosa and essential fatty acids biochemical changes in soybean tempeh (Glycine max) during fermentation process.

Triwibowo R, Andriani M.A.M., Ariviani S. 2016. The stakiosa and essential fatty acids biochemical changes in soybean tempeh (Glycine max) during fermentation process. Bioteknologi 13: 34-41. Soybean tempeh is a food that is known by the people of Indonesia. It is known to have levels of stakiosa which causes flatulensi lower than soybean. It is also known to have levels of essential fatty acids (oleic acid, linoleic, and linolenic), which is higher than soybean. This study aims to determine changes in levels of stakiosa and essential fatty acids (oleic acid, linoleic, and linolenic) during the fermentation process. The determination of stakiosa used High Performance Liquid Chromatography method (AOAC 1999). The determination of essential fatty acids include oleic acid, linoleic, and linolenic used Gas Chromotograpy method (Park and Goins 1994). This research are expected to provide an alternative optimal fermentation time observed from the lowest level of stakiosa and the high level of essential fatty acid. The results showed that stakiosa levels of soybean tempeh decreased over the longer fermentation. The percentage of the highest decrease level of stakiosa found in 24 hours fermentation. While changes in level of oleic acid, linoleic acid, and linolenic acid in soybean tempeh fermentation for 96 hours has the same pattern. The lowest level of essential fatty acids found in 48 hours fermentation time and the highest in 96 hours fermentation.

발효 김치로부터 분리한 Lactobacillus sp. Strain KYH를 이용한 진생베리 추출물 최적 발효 공정 확립 및 생성물의 특성 분석

The pharmacological effects of ginseng berry have been known to improve psychological function, immune activities, cardiovascular conditions, and certain cancers. It is also known that fermentation improves the bioavailability of human beneficial natural materials. Accordingly, we investigated the optimal fermentation conditions of ginseng berry extract with strain isolated from conventional foods. We also analyzed the fermentation product and its antioxidant activity. The bacterium isolated from fermented kimchi was identified as Lactobacillus sp. strain KYH. To optimize the process, fermentation was performed in a 5 L fermenter containing 3 L of ginseng berry extract at 200 rpm for 72 hr. Under optimized conditions, batch and fed-batch fermentations were performed. After fermentation, organic acids, amino acids, sugars, ginsenosides, and antioxidant activity were evaluated. The optimum fermentation conditions were determined as pH 7.0 and a temperature of 30˚C, respectively. After fermentation, the amounts and compositions of organic acids, amino acids, sugars, ginsenosides, and antioxidant activity were altered. In comparing the distribution of ginsenosides with that before fermentation, the ginsenoside Re was a major product. However, amounts of ginsenosides Rb1, Rc, and Rd were reduced, whereas amounts of ginsenosides Rh1 and Rh2 increased. Total phenol content increased to 43.8%, whereas flavonoid content decreased to 19.8%. The DPPH radical scavenging activity and total antioxidant activity increased to 27.2 and 19.4%, respectively.

Storage characteristics, nutritive value, and fermentation characteristics of alfalfa packaged in large-round bales and wrapped in stretch film after extended time delays

The production of baled silage is attractive to producers because it offers advantages over dry hay, particularly by limiting risks associated with wet or unstable weather conditions. Our objectives were to test the effects of delayed wrapping on silage fermentation, storage characteristics, and the nutritive value of baled alfalfa silages. To accomplish this, large-round bales of alfalfa were wrapped in plastic film within 4h of baling (d 0), or after delays of 1, 2, or 3 d. A secondary objective was to evaluate a prototype bale wrap containing an O2-limiting barrier (OB) against an identical polyethylene wrap without the O2 barrier (SUN). Sixty-four 1.19×1.25-m bales of alfalfa were made from 4 field blocks at a mean moisture concentration of 59.1±4.3% with a mean initial wet bale weight of 473±26.4kg. Two bales per field block were assigned to each combination of bale wrap (SUN or OB) and wrapping time (0, 1, 2, or 3 d postbaling), and one bale of each pair was fitted with a thermocouple placed in the geometric center of each bale. All bales were sampled after a 97-d storage period. Internal bale temperatures, recorded at the time bales were wrapped, were greater for all bales with wrapping delays compared with bales wrapped on d 0 (54.9 vs. 34.9°C), and increased to a maximum of 63.9°C after a 3-d delay exhibiting a linear effect of time delay. Total silage fermentation acids (lactic, acetic, propionic, butyric, and isobutyric) were greatest when bales were wrapped on d 0 compared with all bales wrapped with time delays (4.64 vs. 2.26% of DM), and declined with linear and quadratic effects of wrapping delay. Total fermentation acids also were related quadratically to internal bale temperature by regression [y (% of DM)=0.0042x2 – 0.50x + 17.1; R2=0.725]. Similar responses were observed for lactic acid, except that trends were linear, both for orthogonal contrasts evaluating length of wrapping delay, and in regressions on internal bale temperature [y (% of DM)=−0.046x + 3.5; R2=0.663]. Butyric acid also was detected, regardless of treatment, but was greatest within bales wrapped on d 0 compared with those with wrapping delays (0.99 vs. 0.38% of DM), and a similar response (0.68 vs. 0.52% of DM) was observed for NH3-N, suggesting that clostridial activity occurred during silage fermentation. Based on these results, silage fermentation characteristics and the nutritive value declined with time delays before wrapping, but responses were exacerbated when delays exceeded 1 d.

Proliferation of Microorganisms in Acidic Fermentation of <i>Elaeis guineensis</i> L. Waste

An investigation into the type of fermentation oil palm fruit waste undergoes and the probable microorganisms involved within a short period was carried out using simple fermenter. The temperature was determined using mercury thermometer, the pH of the medium was monitored with calibrated pH meter and the titratable acidic was determined using standard technique. The microbial profile of the medium was also evaluated using standard procedures. The highest temperature value was observed at day 0 (32.65°C) and the lowest at day 1 (29.50°C). The pH values of the fermentation oil palm fruit waste ranged between 4.15 - 4.60. The highest pH value was obtained at day 3 of the fermentation which was 4.60. The titratable acidity showed variation from day 0 - 2 and then with a continuous decrease till day 5. The least titratable acidity was obtained at day 5 (0.03) and the highest at day 2 (0.77). Bacteria load decreases from 1.0 × 108 - 1.6 × 107 cfu/ml, while the fungi population increases from day 0 to day 5 of the fermentation period (1 × 103 - 2 × 104 sfu/ml). Bacterial isolates obtained were Micrococcus leteus, Proteus vulgaris, Bacillus cereus, Baccillus subtilis, and Staphylococcus aureus while the fungal isolates obtained were Aspergillus niger, Neurospora crassa, Brachysporium spp, and Saccharomyces cerevisiae. It can be concluded that oil palm waste fermentation is an acidic fermentation that involved mesophiles microbes. And with these, several tons of oil palm epicarp waste can be optimally fermented (though with further research) and used for other purposes thereby reducing environmental pollution that would have resulted leaving this oil palm fruit waste in the environment.

Discovery and History of Amino Acid Fermentation.

There has been a strong demand in Japan and East Asia for L-glutamic acid as a seasoning since monosodium glutamate was found to present umami taste in 1907. The discovery of glutamate fermentation by Corynebacterium glutamicum in 1956 enabled abundant and low-cost production of the amino acid, creating a large market. The discovery also prompted researchers to develop fermentative production processes for other L-amino acids, such as lysine. Currently, the amino acid fermentation industry is so huge that more than 5 million metric tons of amino acids are manufactured annually all over the world, and this number continues to grow. Research on amino acid fermentation fostered the notion and skills of metabolic engineering which has been applied for the production of other compounds from renewable resources. The discovery of glutamate fermentation has had revolutionary impacts on both the industry and science. In this chapter, the history and development of glutamate fermentation, including the very early stage of fermentation of other amino acids, are reviewed.

Efficient production of citric acid in segmented fermentation using Aspergillus niger based on recycling of a pellet-dispersion strategy

Segmentation recycling fermentation based on a pellet-dispersion strategy to reconstruct the traditional citric acid batch fermentation process is reported.

PEMBUATAN BIOETANOL DARI KUPASAN KENTANG (Solanum tuberosum L.) DENGAN PROSES FERMENTASI

Ethanol fermented from potato peels is proposed as one alternative source of renewable energy called bioethanol. In this research bioethanol was produced through four stages namely acid hydrolysis, detoxification, fermentation and distillation. The acid hydrolysis process was carried out using sulphuric acid at 100oC for 60 minutes. The detoxification process was carried out by adding NH4OH into the hydrolyzate prior to fermentation. Distillation was performed up to 100oC and the distillate with the BP of 78-84oC was determined for its ethanol content using gas chromatography. The ethanol produced from 5 grams of dried potato peels through fermentation for 4, 5, 6, and 7 days 3.54%; 4,85%; 5,35%; and 6.15% respectively.

Steering Endogenous Butyrate Production in the Intestinal Tract of Broilers as a Tool to Improve Gut Health.

The ban on antimicrobial growth promoters and efforts to reduce therapeutic antibiotic usage has led to major problems of gastrointestinal dysbiosis in livestock production in Europe. Control of dysbiosis without the use of antibiotics requires a thorough understanding of the interaction between the microbiota and the host mucosa. The gut microbiota of the healthy chicken is highly diverse, producing various metabolic end products, including gases and fermentation acids. The distal gut knows an abundance of bacteria from within the Firmicutes Clostridium clusters IV and XIVa that produce butyric acid, which is one of the metabolites that are sensed by the host as a signal. The host responds by strengthening the epithelial barrier, reducing inflammation, and increasing the production of mucins and antimicrobial peptides. Stimulating the colonization and growth of butyrate-producing bacteria thus may help optimizing gut health. Various strategies are available to stimulate butyrate production in the distal gut. These include delivery of prebiotic substrates that are broken down by bacteria into smaller molecules which are then used by butyrate producers, a concept called cross-feeding. Xylo-oligosaccharides (XOS) are such compounds as they can be converted to lactate, which is further metabolized to butyrate. Probiotic lactic acid producers can be supplied to support the cross-feeding reactions. Direct feeding of butyrate-producing Clostridium cluster IV and XIVa strains are a future tool provided that large scale production of strictly anaerobic bacteria can be optimized. Current results of strategies that promote butyrate production in the gut are promising. Nevertheless, our current understanding of the intestinal ecosystem is still insufficient, and further research efforts are needed to fully exploit the capacity of these strategies.

Production of polymalic acid and malic acid from xylose and corncob hydrolysate by a novel Aureobasidium pullulans YJ 6–11 strain

Polymalic acid (PMA) is a water-soluble biopolymer with many attractive properties for pharmaceutical applications. Its monomer, l-malic acid, is a potential C4 platform chemical, which is widely used in the food industry. In this study, a new strain with a high PMA yield from xylose was isolated and identified as Aureobasidium pullulans based on the morphological and phylogenetic analyzes. This strain produced PMA from xylose at a comparable or higher rate than glucose, and PMA produced from xylose had a similar molecular weight to that produced from glucose. A high final PMA titer of 80.4g/L (91.2g/L of malic acid after hydrolysis) was achieved using fed-batch fermentation with xylose in a 5-L fermentor at a PMA productivity of 0.52g/Lh. Corncob hydrolysate could be better utilized producing 28.6g/L of PMA (or 32.4g/L malic acid) in batch fermentation. PMA was further characterized for its chemical structure. This strain can be used to produce PMA and malic acid from xylose and lignocellulosic biomass hydrolysates.