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The purpose of this work was to analyze and evaluate the functional properties of a new nanoemulsion that contained cordycepin. Droplet size and distribution were measured, and the stability of the nanoemulsion in different storage conditions was evaluated. We also tested skin irritation caused by the nanoemulsion, cordycepin stability in the nanoemulsion, anti-aging effect, and microbial challenge. The nanoemulsion was homogeneous with proper dispersion stability, and cordycepin was stable for eight months within the cosmetic nanoemulsion. The nanoemulsion did not irritate human hand and face skin, and the cosmetic nanoemulsion was effective in preventing microbial contamination of the product during use and storage. The new nanoemulsion containing cordycepin satisfied provisions of the 2015 Safety and Technical Standards for Cosmetics of the Ministry of Health, People’s Republic of China.

Additional file 1: Table S1. The pH in soil in different treatments of the 60th day.

Chaetominine (CHA), an alkaloid with biological activity produced by Aspergillus fumigatus CY018, has strong anticancer activity against the human leukemia cell. However, its further research for pharmacokinetics is limited by CHA production in submerged fermentation, which is a problem urgently awaiting solutions by effective biological strategies. In this work, Ca2+ and Al3+ exhibited a strong promoting effect on CHA production after multiple metal ions screening. Then, the concentration of Ca2+ and Al3+ and the addition time was optimized. The suitable conditions were 0.5 mM Ca2+ and 0.5 mM Al3+ at 120 h, in which the CHA production reached 58.5 and 49.45 mg/L with optimized condition of Ca2+ and Al3+ respectively. The intermediate metabolites, such as DAHP, chorismate and tryptophan, were increased obviously with addition of Ca2+ and Al3+. The activities of key enzymes of DAHPs, AroAs and TrpCs in CHA biosynthesis pathway were improved by 3.58-, 3.60- and 3.34-folds respectively. Meanwhile, the transcription levels of laeA, dahp, cs, and trpC were upregulated by 3.22-, 12.65-, 5.58- and 6.99-fold respectively by addition of Ca2+ and Al3+. Additionally, the fermentation strategy was successfully scaled up to 5 L reactor, in which CHA production could attain 75.6 mg/L at 336 h. This work demonstrated that Ca2+ and Al3+ co-addition was an effective strategy for increasing CHA production, and the information obtained might be useful to the further improvement of CHA fermentation on large scale.

Freshly harvested Jerusalem artichoke tubers contain inulinase, which needs to be inactivated. Otherwise, inulin from Jerusalem artichokes is easily hydrolyzed by inulinase into fructose, which can be lost or consumed by bacteria during the marination process. The traditional pickling process lasts for six months, and a large amount of salt (18%–20%) is added during the pickling process. This production process is uneconomical and increases nitrite intake, and the miscellaneous bacteria that are produced during the pickling process affect product taste. In this study, reasonable enzyme inactivation methods, including NaCl, NaHCO3, and ultrasound, were evaluated. NaHCO3 showed the strongest enzyme inactivation; however, the quality and flavor of the obtained Jerusalem artichoke pickles were not ideal. The sensory flavor of Jerusalem artichoke pickles inactivated by NaCl was better, and enzyme inactivation was not obvious after ultrasound treatment, but ultrasound combined with NaCl resulted in enzyme inactivation. The inulinase activity of Jerusalem artichokes was reduced to 2.50 U/mL, and the inulin content was maintained at 61.22%, when the ultrasonic and NaCl combination treatment was applied. The strain LS3, identified as Enterococcus faecalis, and YS5, identified as salt-tolerant yeast Meyerozyma guilliermondii, were the dominant microorganisms isolated from the pickle juice. Jerusalem artichokes with inactivated inulinase were pickled with microbial powder, separated, purified, and dried to remove the natural Jerusalem artichoke sauce. This workflow shortened the fermentation cycle and improved product quality.

Barley grass possesses high nutritional value and antioxidant properties. In this study, the phytochemical constituents and antioxidant enzyme activities in six cultivars of barley grass were explored at three developmental stages: tillering, jointing, and booting stages. Total chlorophyll (Chl t) and carotenoid (Car) content, chlorophyll a/b (Chl a/b) ratio, total nitrogen nutrition (TNN), and total soluble protein (TSP) content, and superoxide dismutase (SOD), peroxidase (POD), and polyphenol oxidase (PPO) activities were assayed. The results indicated that the cultivar &times, development interaction was significant and that developmental stage was the main factor affecting the parameters studied. Cultivars had a negligible effect on these parameters, which varied with the developmental stages. In the tillering stage, Chl t and Car content, TNN, and POD activity achieved their highest value, in the jointing stage, SOD activity peaked, in the booting stage, Chl a/b ratio, TSP content, and PPO activity showed their highest values. TNN showed a negative correlation with TSP. Compared with those in the jointing, Chl t, Car, TSP, TNN content, Chl a/b ratio, and POD and PPO activities increased in the booting and the tillering stages, whereas SOD activity decreased. The differences in phytochemical constituents and antioxidant enzyme activities in barley grass were mainly correlated with the developmental stages. The aim of this study was to demonstrate the influence of developmental stages of barley grass on its phytochemical profile and antioxidant activities. Our results will help understand the mechanism of action of barley grass and provide theoretical support for the therapeutic application of barley grass.

Compressive creep of corundum-mullite refractories is an important performance to measure whether they can be used stably for a long time at high temperature. Therefore, a compressive creep prediction method of corundum-mullite refractory based on BP neural network is proposed. The inputs of the BP neural network are the content of Al2O3, SiO2, Fe2O3 and the time of high temperature whereas creep rate is the output. The results show that the predicted results can correspond well with the experimental results. The developed BP neural network model can efficiently and accurately predict the creep rate of corundum-mullite refractories.