3-Amino-4-hydroxybenzoic acid production from glucose and/or xylose via recombinant Streptomyces lividans.

The aromatic compound 3-amino-4-hydroxybenzoic acid (3,4-AHBA) can be employed as a raw material for high-performance industrial plastics. The aim of this study is to produce 3,4-AHBA via a recombinant Streptomyces lividans strain containing griI and griH genes derived from Streptomyces griseus using culture medium with glucose and/or xylose, which are the main components in lignocellulosic biomass. Production of 3,4-AHBA by the recombinant S. lividans strain was successful, and the productivity was affected by the kind of sugar used as an additional carbon source. Metabolic profiles revealed that L aspartate-4-semialdehyde (ASA), a precursor of 3,4-AHBA, and coenzyme NADPH were supplied in greater amounts in xylose medium than in glucose medium. Moreover, cultivation in TSB medium with a mixed sugar (glucose/xylose) was found to be effective for 3,4-AHBA production, and optimal conditions for efficient production were designed by changing the ratio of glucose to xylose. The best productivity of 2.70 g/L was achieved using a sugar mixture of 25 g/L glucose and 25 g/L xylose, which was 1.5 times higher than the result using 50 g/L glucose alone. These results suggest that Streptomyces is a suitable candidate platform for 3,4-AHBA production from lignocellulosic biomass-derived sugars under appropriate culture conditions.

Potential legal issues when caring healthcare robot with communication in caring functions are used for older adult care

The issue of older adults' care is becoming a serious concern in Japan, which has a rapidly aging population and a low birthrate. The development of robots is pushed forward as a measure to compensate for the healthcare worker shortage. The purpose of this paper is to consider the potential legal issues of caring healthcare robot (CHR) for older adults' care. A CHR must recognize the speech, face, and presence of older adults, and make judgments and relay information based on acquired information. CHRs fulfill the caring function by being close to patients, to know them deeply, and to look after them. Therefore, communication functions by advanced artificial intelligence based on caring in nursing are essential for CHRs. The ability to maintain and improve the activities of daily living (ADL) of older adults is to facilitate activities through bidirectional information relay. Furthermore, without guarantees on the safety and ascription of responsibilities, the introduction of CHRs in clinical practice will not proceed. As laws differ from country to country, it is necessary to examine Japanese policies and related laws when using CHRs in Japan. Currently, there are no central rules on information security. In Japan, the law is made after a case has occurred; thus, dealing with novel issues as they occur will not have the benefit of legal guidance. Creating a broad legal framework or taking preventive measures at an early stage is needed. Therefore, as a first step, establishing guidelines for the use of CHRs will be valuable

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3-Amino-4-hydroxybenzoic acid production from sweet sorghum juice by recombinant Corynebacterium glutamicum.

The production of the bioplastic precursor 3-amino-4-hydroxybenzoic acid (3,4-AHBA) from sweet sorghum juice, which contains amino acids and the fermentable sugars sucrose, glucose and fructose, was assessed to address the limitations of producing bio-based chemicals from renewable feedstocks. Recombinant Corynebacterium glutamicum strain KT01 expressing griH and griI derived from Streptomyces griseus produced 3,4-AHBA from the sweet sorghum juice of cultivar SIL-05 at a final concentration (1.0 g l(-1)) that was 5-fold higher than that from pure sucrose. Fractionation of sweet sorghum juice by nanofiltration (NF) membrane separation (molecular weight cut-off 150) revealed that the NF-concentrated fraction, which contained the highest concentrations of amino acids, increased 3,4-AHBA production, whereas the NF-filtrated fraction inhibited 3,4-AHBA biosynthesis. Amino acid supplementation experiments revealed that leucine specifically enhanced 3,4-AHBA production by strain KT01. Taken together, these results suggest that sweet sorghum juice is a potentially suitable feedstock for 3,4-AHBA production by recombinant C. glutamicum.

Phenyllactic acid production by simultaneous saccharification and fermentation of pretreated sorghum bagasse.

Dilute acid-pretreated sorghum bagasse, which was predominantly composed of glucan (59%) and xylose (7.2%), was used as a lignocellulosic feedstock for d-phenyllactic acid (PhLA) production by a recombinant Escherichia coli strain expressing phenylpyruvate reductase from Wickerhamia fluorescens. During fermentation with enzymatic hydrolysate of sorghum bagasse as a carbon source, the PhLA yield was reduced by 35% compared to filter paper hydrolysate, and metabolomics analysis revealed that NAD(P)H regeneration and intracellular levels of erythrose-4-phosphate and phosphoenolpyruvate for PhLA biosynthesis markedly reduced. Compared to separate hydrolysis and fermentation (SHF) with sorghum bagasse hydrolysate, simultaneous saccharification and fermentation (SSF) of sorghum bagasse under glucose limitation conditions yielded 4.8-fold more PhLA with less accumulation of eluted components, including p-coumaric acid and aldehydes, which inhibited PhLA fermentation. These results suggest that gradual enzymatic hydrolysis during SSF enhances PhLA production under glucose limitation and reduces the accumulation of fermentation inhibitors, collectively leading to increased PhLA yield.