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The grain‐based ethanol production has been increasing as the demand for biofuel additives increased, and the fossil fuel sources decreased. Distillers dried grains with solubles (DDGS) are a primary coproduct of bioethanol plants of the conventional corn dry‐grind process. With increasing corn‐based ethanol production, DDGS production is increased, and it has become a global commodity. Despite the high nutritional value of DDGS, however, its uses are still not fully explored. This review aims to provide a comprehensive summary of the DDGS production process, chemical and physical properties, nutritional value, and the potential of using DDGS in cattle, fish, poultry feed, and human foods. The challenges of using DDGS in animal feed and human food are discussed. Distillers dried grains with solubles has been identified as a protein substitute that is both readily available and competitively priced (per unit protein) compared to other conventional alternative protein sources. Researchers have discovered measures to boost DDGS quality and safety. Several approaches have been proposed to improve the DDGS digestibility and nutritional value. Although the benefits and risks associated with the DDGS uses are identified, more research is required to regulate the quality and safety standards for DDGS. Versatile applications of DDGS will valorize this coproduct. The development of DDGS utilization enhances health and functional benefits to animals and humans; it also assists bioethanol plants economically. The information will not only provide knowledge of DDGS in terms of its production process, nutritional value, and applications but, more importantly, explore the opportunities of developing new uses of this under‐utilized commodity.

Spermidine is a biologically active polyamine with extensive application potential in functional foods. However, previously reported spermidine titers by biosynthesis methods are relatively low, which hinders its industrial application. To improve the spermidine titer, key genes affecting the spermidine production were mined to modify Bacillus amyloliquefaciens. Genes of S-adenosylmethionine decarboxylase (speD) and spermidine synthase (speE) from different microorganisms were expressed and compared in B. amyloliquefaciens. Therein, the speDfrom Escherichia coliand speEfrom Saccharomyces cerevisiaewere confirmed to be optimal for spermidine synthesis, respectively. Gene and amino acid sequence analysis further confirmed the function of speDand speE. Then, these two genes were co-expressed to generate a recombinant strain B. amyloliquefaciensHSAM2(PDspeD-SspeE) with a spermidine titer of 105.2 mg/L, improving by 11.0-fold compared with the control (HSAM2). Through optimization of the fermentation medium, the spermidine titer was increased to 227.4 mg/L, which was the highest titer among present reports. Moreover, the consumption of the substrate S-adenosylmethionine was consistent with the accumulation of spermidine, which contributed to understanding its synthesis pattern. In conclusion, two critical genes for spermidine synthesis were obtained, and an engineering B. amyloliquefaciensstrain was constructed for enhanced spermidine production.

This study investigates the properties and potential applications of phycoerythrin 545, a naturally occurring light-harvesting pigment protein from Rhodomonas salina. Phycoerythrin 545, characterized by its bright red color and maximum absorption wavelength at 545 nm, was extracted using freeze–thawing methods, further purified, and analyzed using chromatographic, spectroscopic techniques, and sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Phycoerythrin 545 consists of two subunits, primarily α and β, but lacks the γ subunit, and is stable at 4 °C within a pH range of 3–10. To further characterize it, its susceptibility to degradation by trypsin was assessed. The biological activity of phycoerythrin 545 and its degradation products were investigated in HT29 human colon cancer cells. The results showed that the degradation products, particularly those within 3–10 kDa, significantly decreased the viability of HT29 cells by inducing apoptosis. Mechanistic studies indicated these effects were mediated through the activation of mitogen-activated protein kinase (MAPK)/extracellular signal-regulated kinases and MAPK/c-Jun N-terminal Kinase signaling pathways and involved the regulation of key apoptotic proteins such as p53, Bim, Bad, Bak, and Bax, leading to the activation of the Caspase-3 apoptotic pathway. These findings contribute to understanding the structural and functional properties of phycoerythrin 545, laying a foundation for its exploration in food industry applications and cancer therapy supplementation.

Zizyphi SpinosaeSemen (ZSS) is an herbal medicine with a variety of biological activities. In this study, the oil fraction of ZSS was extracted using an ultrasonic assisted extraction (UAE) method and the value of this underutilized byproduct was explored. The effects of operational parameters of the UAE process (extraction temperature, extraction time, liquid-to-solid ration, and ultrasonic power) on the extraction efficiency were evaluated based on the yield of vitamin E and the squalene, two important compounds in ZSS oil with antioxidant bioactivities. A central composite design was used to optimize these operational parameters. The optimized UAE process resulted in a vitamin E yield of 29.58 ± 0.19 mg/100 g ZSS and a squalene yield of 820.49 ± 3.66 µg/100 g ZSS, which were much higher than those obtained through the conventional heating reflux extraction (HRE) (i.e., vitamin E yield of 18.67 mg/100 g ZSS, and squalene yield of 627.25 µg/100 g ZSS). The ZSS oil contained oleic acid and linoleic acid as the main fatty acid. In addition, the UAE-derived ZSS oil exhibited stronger activities of scavenging ABTs, superoxide anions and hydroxyl radicals, compared to the ZSS oil extracted from HRE. Collectively, this work demonstrated that UAE was an effective method to extract ZSS oil with high yield. The ZSS oil can be used as a potential an antioxidant agent in food and pharmaceutical industries.

A simple high performance liquid chromatography (HPLC) method was established for identification and quantification of nine polyphenols (gallic acid, chlorogenic acid, caffeic acid, myricetrin, hyperoside, luteoloside, quercitrin-3-rhamnoside, quercetin and kaempferol) in Polygoni Avicularis Herba. The analysis was performed on a Pinnacle II C18column (250 × 4.6 mm, 5.0 µm) with a gradient elution of an aqueous mobile phase (containing 0.3% acetic acid) modified by acetonitrile. Diode-array detector (DAD) was used to detect the analytes at four wavelengths (270, 326, 355, and 370 nm). The established method was validated with good linearity, precision, accuracy and reproducibility to determine the polyphenols in Polygoni Avicularis Herba. The applicability of this analytical method was confirmed by successful analysis of the herb samples. The results indicated that the contents of these polyphenols varied with different locations of the samples. The anti-oxidation activities of Polygoni Avicularis Herba were further evaluated based on DPPH, ABTS and superoxide anion free radical scavenging assay. The herb exhibited obvious radical scavenging capacity, and gallic acid, chlorogenic acid, myricetrin and hyperoside played important roles in this activity.

Ammonia gas emission is a major concern in concentrated animal production operations. It not only reduces the manure value as fertilizer due to nitrogen loss, but also has considerable environmental consequences for both animals and ecosystem. In this work, a microalgae culture system was developed as an ammonia gas bioscrubber to reduce ammonia gas emission. The green algae Scenedesmus dimorphuswas grown in a flat-panel photobioreactor aerated with ammonia-laden air. A continuous culture was performed at different operational conditions including dilution rate (D = 0.05, 0.1, 0.2, and 0.3 day−1), ammonia gas loading rate (9.4, 19.3, 28.9, 39.9, 55.6 mg/L-day), and medium pH (5, 6, 7, and 8). The alga culture at 0.1 day−1dilution rate, 39.9 mg/L-day ammonia gas loading rate, and pH 7 resulted in the highest cell density and biomass productivity. In order to provide a wide spectrum evaluation of the algae-based ammonia mitigation system, four parameters were determined, including ammonia removal rate, overall ammonia gas removal efficiency, cellular ammonia consumption rate, and cell yield based on ammonia input. Depending on the operational conditions used, the maximum values of those four evaluative parameters were 50.92 ± 2.91 mg/L-day of ammonia removal rate, 94.90 ± 1.87% of ammonia removal efficiency, 0.0597 ± 0.0024 g NH3/g cell-day of cellular ammonia consumption rate, and 19.40 ± 2.52 g cell/g NH3of cell yield based on ammonia. It was also found that the majority of nitrogen in the ammonia gas was assimilated by the algal cells. At D = 0.1 day−1, 39.9 mg/L-day of ammonia gas loading rate and pH 7, algal biomass assimilated 98.6% of nitrogen contained in the ammonia gas input, with less than 5% of inlet ammonia gas was exhausted after the algal treatment.Implications:This study demonstrated the effectiveness of using microalgae for mitigating ammonia gas emission from animal production operations. The results enabled us to better understand the mechanisms of ammonia assimilation by microalgae, the engineering design parameters for the process scale up, and the economic viability of the system. Eventually, it will lead to a novel, alternative method for mitigating ammonia gas emission from concentrated animal operations while producing biomass as high-quality feed ingredient.

Abstract: A cellulase production process was developed by growing the fungi Trichoderma reesei and Aspergillus phoenicis on dairy manure. T. reesei produced a high total cellulase titer (1.7 filter paper units [FPU]/mL, filter paper activity) in medium containing 10 g/L of manure (dry basis [w/w]), 2 g/L KH2PO4, 2 mL/L of Tween-80, and 2mg/L of CoCl2. However, β-glucosidase activity in the T. reesei-enzyme system was very low. T. reesei was then cocultured with A. phoenicis to enhance the β-glucosidase level. The mixed culture resulted in a relatively high level of total cellulase (1.54 FPU/mL) and β-glucosidase (0.64 IU/mL). The ratio of β-glucosidase activity to filter paper activity was 0.41, suitable for hydrolyzing manure cellulose. The crude enzyme broth from the mixed culture was used for hydrolyzing the manure cellulose, and the produced glucose was significantly (p<0.01) higher than levels obtained by using the commercial enzyme or the enzyme broth of the pure culture T. reesei.

This study focused on the effect of hemicellulose and lignin on enzymatic hydrolysis of dairy manure and hydrolysis process optimization to improve sugar yield. It was found that hemicellulose and lignin in dairy manure, similar to their role in other lignocellulosic material, were major resistive factors to enzymatic hydrolysis and that the removal of either of them, or for best performance, both of them, improved the enzymatic hydrolysis of manure cellulose. This result combined with scanning electron microscope (SEM) pictures further proved that the accessibility of cellulose to cellulase was the most important feature to the hydrolysis. Quantitatively, fed-batch enzymatic hydrolysis of fiber without lignin and hemicellulose had a high glucose yield of 52% with respect to the glucose concentration of 17 g/L at a total enzyme loading of 1300 FPU/L and reaction time of 160 h, which was better than corresponding batch enzymatic hydrolysis.

A biorefinery process that utilizes cheese whey as substrate to simultaneously produce nisin, a natural food preservative, and lactic acid, a raw material for biopolymer production, was studied. The conditions for nisin biosynthesis and lactic acid coproduction by Lactococcus lactissubsp. lactis(ATCC 11454) in a whey-based medium were optimized using statistically based experimental designs. A Plackett-Burman design was applied to screen seven parameters for significant factors for the production of nisin and lactic acid. Nutrient supplements, including yeast extract, MgSO4, and KH2PO4, were found to be the significant factors affecting nisin and lactic acid formation. As a follow-up, a central-composite design was applied to optimize these factors. Second-order polynomial models were developed to quantify the relationship between nisin and lactic acid production and the variables. The optimal values of these variables were also determined. Finally, a verification experiment was performed to confirm the optimal values that were predicted by the models. The experimented results agreed well with the model prediction, giving a similar production of 19.3 g/L of lactic acid and 92.9 mg/L of nisin.