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BACKGROUND: Ergothioneine (EGT) is a high‐value food functional factor that cannot be synthesized by humans and other vertebrates, and the low yield limits its application. RESULTS: In this study, the optimal fermentation temperature, fermentation time, initial pH, inoculum age, and inoculation ratio on EGT biosynthesis of Rhodotorula mucilaginosa DL‐X01 were optimized. In addition, the effects of three key precursor substances – histidine, methionine, and cysteine – on fungal EGT synthesis were verified. The optimal conditions were further obtained by response surface optimization. The EGT yield of R. mucilaginosa DL‐X01 under optimal fermentation conditions reached 64.48 ± 2.30 mg L−1 at shake flask fermentation level. Finally, the yield was increased to 339.08 ± 3.31 mg L−1 (intracellular) by fed‐batch fermentation in a 5 L bioreactor. CONCLUSION: To the best of our knowledge, this is the highest EGT yield ever reported in non‐recombinant strains. The fermentation strategy described in this study will promote the efficient biosynthesis of EGT in red yeast and its sustainable production in the food industry. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Abstract Ergothioneine (EGT) is a high-value natural sulfur-containing amino acid and has been shown to possess extremely potent antioxidant and cytoprotective activities. At present, EGT has been widely used in food, functional food, cosmetics, medicine, and other industries, but its low yield is still an urgent problem to overcome. This review briefly introduced the biological activities and functions of EGT, and expounded its specific applications in food, functional food, cosmetic, and medical industries, introduced and compared the main production methods of EGT and respective biosynthetic pathways in different microorganisms. Furthermore, the use of genetic and metabolic engineering methods to improve EGT production was discussed. In addition, the incorporation of some food-derived EGT-producing strains into fermentation process will allow the EGT to act as a new functional factor in the fermented foods. [ABSTRACT FROM AUTHOR]

[Display omitted] • Untreated molasses could be utilized by R. mucilaginosa DL-X01 as carbon source. • Fish bone meal enzymatic hydrolysate was used to replace yeast extract and peptone. • The amount of molasses and fish bone meal added were optimized. • Feedstock cost of producing EGT is reduced by 331 % compared to using YPD broth. Ergothioneine (EGT) is a high-value natural antioxidant that cannot be synthesized by the human body. This study showed that Rhodotorula mucilaginosa DL-X01 can use untreated molasses and fish bone meal enzymatic hydrolysate as the substrates to synthesize EGT. By optimizing the growth conditions, the EGT yield reached 29.39 mg/L when molasses and fish bone meal (FBM) were added at 60 g/L and 400 g/L respectively. Finally, the EGT yield was increased to 216.25 mg/L by fed-batch fermentation in a 5 L bioreactor. Compared with the fermentation by yeast extract peptone dextrose medium, the feedstock cost of EGT production was reduced by 330.91 % by using molasses and FBM as substrates. These results showed that R. mucilaginosa DL-X01 can produce high-value EGT using two cheap processing by-products, molasses and FBM, which is of great significance for environmental protection and sustainable development. [ABSTRACT FROM AUTHOR]

Red sour soup is a traditional fermented product in southwest China. Currently, the existing production process mainly adopts the method of natural fermentation, with long fermentation cycles and poor stability between batches. Rapid establishment of dominant strains can accelerate the formation of lactic acid, which can inhibit the growth of miscellaneous bacteria. It is also helpful for the inhibition of nitrite accumulation, shortening of fermentation. In this study, the dominant strain H9, with lactic acid‐producing ability, was isolated from the natural fermented red sour soup, and was identified as Lactobacillus buchneri, based on the 16s rRNA sequence analysis and biochemical identification. Then, the optimization of fermentation conditions was performed using L. buchneri H9 strain as external bacteria. The optimized fermentation conditions were temperature of 22°C, starch dosage of 11.24 g/L, and initial inoculation of 3.5 × 108 cfu/L. The concentration of lactic acid reached 8.029 g/L after 8 days of inoculating fermentation, which exceeded 6.221 g/L for 20 days of natural fermentation. Compared with natural fermentation, the peak of nitrite during inoculating fermentation appeared earlier and the peak height was lower. While the nitrite content in inoculating fermentation decreased to safety threshold more quickly. The volatile flavor compounds analysis showed that 41 types of volatile compounds were detected in the inoculating fermentation product, while 45 in the natural fermentation product. Over 88% compounds were overlapped, which means similar flavor between two fermentation products. These results provide a sufficient scientific basis for the industrialized production of inoculating fermentation of red sour soup. [ABSTRACT FROM AUTHOR]

Previous studies suggest that bilinguals' lexical access is language non-selective, especially for orthographically identical translation equivalents across languages (i.e., identical cognates). The present study investigated how such words (e.g., 学校 meaning "school" in both Chinese and Japanese) are processed in the (late) Chinese - Japanese bilingual brain. Using an L2-Japanese lexical decision task, both behavioral and electrophysiological data were collected. Reaction times (RTs), as well as the N400 component, showed that cognates are more easily recognized than non-cognates. Additionally, an early component (i.e., the N250), potentially reflecting activation at the word-form level, was also found. Cognates elicited a more positive N250 than non-cognates in the frontal region, indicating that the cognate facilitation effect occurred at an early stage of word formation for languages with logographic scripts. • The processing of Chinese - Japanese identical cognates was investigated using ERP. • The N400 showed that cognates are more effortlessly processed than non-cognates. • Also, identical cognates elicited a smaller N250 in the frontal region compared to non-cognates. • Cognate effects for the logographic writing systems seem to occur at the orthographic level. [ABSTRACT FROM AUTHOR]

Sentence-final particles (SFPs) as bound morphemes in Japanese have no obvious effect on the truth conditions of a sentence. However, they encompass a diverse range of usages, from typical to atypical, according to the context and the interpersonal relationships in the specific situation. The most frequent particle, -ne , is typically used after addressee-oriented propositions for information sharing, while another frequent particle, -yo , is typically used after addresser-oriented propositions to elicit a sense of strength. This study sheds light on individual differences among native speakers in flexibly understanding such linguistic markers based on their mentalizing ability (i.e., the ability to infer the mental states of others). Two experiments employing electroencephalography (EEG) consistently showed enhanced early posterior negativities (EPN) for atypical SFP usage compared to typical usage, especially when understanding -ne compared to -yo , in both an SFP appropriateness judgment task and a content comprehension task. Importantly, the amplitude of the EPN for atypical usages of -ne was significantly higher in participants with lower mentalizing ability than in those with a higher mentalizing ability. This effect plausibly reflects low-ability mentalizers' stronger sense of strangeness toward atypical -ne usage. While high-ability mentalizers may aptly perceive others' attitudes via their various usages of -ne , low-ability mentalizers seem to adopt a more stereotypical understanding. These results attest to the greater degree of difficulty low-ability mentalizers have in establishing a smooth regulation of interpersonal distance during social encounters. [ABSTRACT FROM AUTHOR]

This study addresses the question of whether native Mandarin Chinese speakers process and comprehend subject-extracted relative clauses (SRC) more readily than object-extracted relative clauses (ORC) in Mandarin Chinese. Presently, this has been a hotly debated issue, with various studies producing contrasting results. Using two eye-tracking experiments with ambiguous and unambiguous RCs, this study shows that both ORCs and SRCs have different processing requirements depending on the locus and time course during reading. The results reveal that ORC reading was possibly facilitated by linear/temporal integration and canonicity. On the other hand, similarity-based interference made ORCs more difficult, and expectation-based processing was more prominent for unambiguous ORCs. Overall, RC processing in Mandarin should not be broken down to a single ORC (dis)advantage, but understood as multiple interdependent factors influencing whether ORCs are either more difficult or easier to parse depending on the task and context at hand. [ABSTRACT FROM AUTHOR]

Ultra-reliable and low-latency communication (URLLC) is one of the main service categories in the fifth-generation communication systems, which lays the foundation for emerging data-exploring video applications with strict end-to-end latency requirement. Unmanned aerial vehicle (UAV) enabled radio access network (UAV-RAN) is an effective architecture to improve the wireless coverage. Combining wireless caching with UAV-RAN is one of the key driving forces to reduce the burden of wireless traffic, provide resilient coverage and reduce the delay in heterogeneous URLLC networks. In this paper, a collaborative caching strategy is proposed for UAV-RANs. First, a scalable video coding (SVC)-based video library is presented to provide users with videos of different perceptual qualities, and the popularity of different definition videos is also analyzed. Then, we propose a heterogeneous network where UAVs within a distance from based station (BS) can be provided with error-free data and UAVs at several stop points can provide data service to users while BS can offer all users data service. Next, an SVC-based two-tier cooperative caching model is proposed, where BS and UAVs store different video encoded files on the basis of caching matrix. Finally, the energy consumption of UAV and the caching hit probability (CHPro) are analyzed, and the optimal caching matrix is obtained via the maximization of CHPro. The maximization problem is proved to be NP hard, and we propose a two-step solution based on the simulated annealing algorithm. Considering URLLC, the average service delay is also analyzed and proved that the proposed strategy is efficient in reducing delay. Simulation results demonstrate that the collaborative caching strategy is more suitable for the UAV-RANs with a skew video popularity library and an ultra-dense user distribution. Compared with other contrasting schemes, the proposed collaborative caching strategy can achieve quasi-optimal performance. [ABSTRACT FROM AUTHOR]