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Lignin valorization through bioconversion to high-value chemicals is crucial for sustainable bioprocessing. Vanillin (VN), a primary lignin derivative, can be transaminated into vanillylamine (VM), a key precursor for capsaicin and pharmaceuticals. This study established a novel self-sufficient redox-complementary whole-cell system, facilitating the recycling of L-alanine and cofactors for efficient VM biosynthesis. Ammonium formate (AF) was employed as amino donor and co-substrate. Recombinant E. coli strain, co-expressing ω-transaminase (CvTA), L-alanine dehydrogenase (ALD), and formate dehydrogenase (FDH), showed higher yield in shorter reaction time compared to the strain expressing only CvTA and ALD. Intermittent feeding strategy was developed to mitigate VN cytotoxicity problem and a remarkable yield of 97.3 ± 1.0% was achieved of VM from 60 mM VN under optimized biotransamination conditions (37 °C, pH 8.0, VN:AF = 1:5, and 1.5 mM NAD + ). Notably, a double-plasmid E. coli recombinant harboring CvTA, ALD, FDH, and aromatic dioxygenase (ADO) was constructed to convert isoeugenol into VM with a 73.2 ± 1.1% yield. This efficient biotransamination platform not only offers a sustainable route to VM for capsaicin production but also promotes lignin valorization for a greener bioeconomy., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Inc. All rights reserved.)

The construction of functional materials via the co-assembly of multimolecular systems has recently emerged as a fascinating topic. The co-assembled multicomponent could promote the evolution of supramolecular assemblies into a high-order nanoarchitecture with improved functional properties. We report the successful preparation of a dual-functional polydiacetylene ( MCPDA-Tz-CA ) having thermochromic and solvatochromic properties via facile co-assembly of MCDA-Tz and cyanuric acid ( MCDA-Tz-CA ) followed by ultraviolet-induced polymerization. Molecular packing patterns from powder X-ray diffraction and density functional theory calculations of molecular self-assembly processes confirm highly ordered co-assembled lamellar structures. MCPDA-Tz-CA showed excellent reversible thermochromism properties when the temperature was increased from 30 to 150 °C with a reversible blue-to-red color transition that could be detected by the naked eye. Also, MCPDA-Tz-CA displayed selective blue-to-red solvatochromism against dimethylformamide and dimethyl sulfoxide. Detailed investigations revealed that the enhanced thermochromic reversibility and solvatochromic selectivity could be attributed to the hydrogen-bonding interactions and the formation of a network structure in the MCDA-Tz /cyanuric acid co-assembly. Our research opens a promising route for improving the performance of functional materials via noncovalent multicomponent arrangements at the molecular level.

Background: Kombucha is a popular fermented drink with therapeutic benefits. The present study aimed to examine the fermentation of turmeric-infused kombucha and evaluate its biological activities and functional properties., Results: The study of pH dynamics during fermentation found that turmeric kombucha has a lower pH decrease than standard kombucha, with the lowest pH of 3.1 being observed in 0.1% turmeric kombucha and the maximum pH of 3.8 found in 1% turmeric kombucha. The research shows that the symbiotic consortia of bacteria and yeast alters during the fermentation process with turmeric. Gas chromatogrphy-mass spectrometry analysis revealed that turmeric kombucha is abundant in terpenes, ketones, alcohols, aldehydes, phenols and fatty acids, with higher levels of active ingredients than regular kombucha. The kombucha with 0.6% turmeric had the highest overall acceptance score (9.0) in sensory evaluation. The total phenolic content after fermentation was in the range 0.2-0.8 mg gallic acid equivalents mL -1 . Increasing turmeric concentrations increased the antioxidant, cytotoxic and antibacterial activity of kombucha analogs, with the highest antioxidant activity (89%) observed at 0.8% turmeric, and the maximum cytotoxicity (74%) and antibacterial activity (zones of inhibition of 17.7 and 15.9 mm against Staphylococcus aureus and Escherichia coli, respectively) observed at 1% turmeric., Conclusion: The fermentation of kombucha infused with turmeric enhanced its biological activities, making it a healthier alternative to traditional kombucha and presenting new opportunities in the field of functional foods. Further investigations into the mechanisms underlying these effects and in vivo studies are warranted to fully comprehend the impact of turmeric kombucha consumption on human health. © 2023 Society of Chemical Industry., (© 2023 Society of Chemical Industry.)

The sustainable extraction of natural compounds has recently attracted significant attention. The extraction of high-quality natural vanillin in active form is crucial for its efficient use in various industries, but conventional solvents are not suitable for this purpose. The flammability, volatility, and toxicity of organic solvents can harm extraction personnel, and their waste liquid can cause environmental pollution. Natural deep eutectic solvents (NADES) are cost-effective, environmentally friendly, biodegradable, and non-toxic organic alternative to conventional solvents. In this study, 20 different NADES were tested for the sustainable extraction of natural vanillin. Among these, a DES system composed of choline chloride: 1,4-butanediol: lactic acid exhibited the highest extraction rate (15.9 mg/g). Employing response surface methodology (RSM), optimal extraction conditions were determined, yielding a vanillin content 18.5 mg/g with water content of 33.9%, extraction temperature of 64.6°C, extraction time of 32.3 min, and a solid-liquid ratio of 44.9 mg/mL. Subsequently, the optimized NADES system was then assessed for reusability in extracting vanillin from vanilla pods and kraft lignin over three cycles, retaining 43% of its extraction efficiency and demonstrating potential for waste reduction. Purification of vanillin was achieved through chromatography using a non-polar resin SP700, with ethanol as a desorption eluent and a feed solution pH of 4.0, resulting in the highest vanillin purity. HPLC and GC-MS analyses confirmed purity, while antioxidant activity assays (DPPH and ABTS) showcased significant antioxidant activity of the purified vanillin. Moreover, vanillin exhibited notable antimicrobial activity against a panel of food-borne bacteria. This study introduces an environmentally friendly approach to vanillin extraction highlights using NADES, emphasizing the potential for producing high-quality bioactive vanillin with reduced environmental impact. The applicability of NADES systems extends beyond vanillin, offering a versatile method for extracting diverse natural compounds., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Xu, Liaqat, Khazi, Sun and Zhu.)

This study investigates the development of dual-substrate mixotrophy strategy to cultivate the microalga Haematococcus lacustris for astaxanthin production. The influence of different concentrations of acetate and pyruvate on biomass productivity was first assessed individually, and then both substrates were used together to improve biomass growth in the green phase and astaxanthin accumulation in red the phase. The results showed that dual-substrates mixotrophy significantly increased the biomass productivity during green growth phase up to 2-fold compared to phototrophic controls. Furthermore, supplementation of dual-substrate to the red phase increased astaxanthin accumulation by 10% in the dual-substrate group compared to single-substrate acetate and no substrate. This dual-substrate mixotrophy approach shows promise for cultivating Haematococcus for commercial production of biological astaxanthin in indoor closed systems., (© 2023 Wiley-VCH GmbH.)

Glycosyltransferases (GTs) catalyze the transfer of active monosaccharide donors to carbohydrates to create a wide range of oligosaccharide structures. GTs display strong regioselectivity and stereoselectivity in producing glycosidic bonds, making them extremely valuable in the in vitro synthesis of oligosaccharides. The synthesis of oligosaccharides by GTs often gives high yields; however, the enzyme activity may experience product inhibition. Additionally, the higher cost of nucleotide sugars limits the usage of GTs for oligosaccharide synthesis. In this review, we comprehensively discussed the structure and mechanism of GTs based on recent literature and the CAZY website data. To provide innovative ideas for the functional studies of GTs, we summarized several remarkable characteristics of GTs, including folding, substrate specificity, regioselectivity, donor sugar nucleotides, catalytic reversibility, and differences between GTs and GHs. In particular, we highlighted the recent advancements in multi-enzyme cascade reactions and co-immobilization of GTs, focusing on overcoming problems with product inhibition and cost issues. Finally, we presented various types of GT that have been successfully used for oligosaccharide synthesis. We concluded that there is still an opportunity for improvement in enzymatically produced oligosaccharide yield, and future research should focus on improving the yield and reducing the production cost., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Self-assembly process represents one of the most powerful and efficient methods for designing functional nanomaterials. For generating optimal functional materials, understanding the pathway complexity during self-assembly is essential, which involves the aggregation of molecules into thermodynamically or kinetically favored pathways. Herein, a functional perylene diimide (PDI) derivative by introducing diacetylene (DA) chains (PDI-DA) is designed. Temperature control pathway complexity with the evolution of distinct morphology for the kinetic and thermodynamic product of PDI-DA is investigated in detail. A facile strategy of UV-induced polymerization is adopted to trap and capture metastable kinetic intermediates to understand the self-assembly mechanism. PDI-DA showed two kinetic intermediates having the morphology of nanosheets and nanoparticles before transforming into the thermodynamic product having fibrous morphology. Spectroscopic studies revealed the existence of distinct H- and J-aggregates for kinetic and thermodynamic products respectively. The polymerized fibrous PDI-DA displayed reversible switching between J-aggregate and H-aggregate., (© 2023 Wiley-VCH GmbH.)

Chitosanases are potential candidates for chitooligosaccharides (COS) production-based industries, therefore, the discovery of chitosanases having commercial potential will remain a priority worldwide. This study aims to characterize different chitosanases of Bacillus strains for COS production. Six different indigenous Bacillus strains (B. cereus EGE-B-6.1m, B. cereus EGE-B-2.5m, B. cereus EGE-B-5.5m, B. cereus EGE-B-10.4i, B. thuringiensis EGE-B-3.5m, and B. mojavensis EGE-B-5.2i) were used to purify and characterize chitosanases. All purified chitosanases have a similar molecular weight (37 kDa) as determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. However, other characteristics such as optimum temperature and pH, kinetic parameters (K m and V max ), temperature, and pH stabilities were dissimilar among the strains of different Bacillus species and within the same species. Furthermore, chitosanases of all strains were able to successfully hydrolyze chitosan to COS and oligomers of the degree of polymerization 2-6 were detected with chitobiose and chitotriose as major hydrolysis products. The relative yields of COS were in a range of 19%-31% and chitosanase of B. thuringiensis EGE-B-3.5m turned out to be the best enzyme in terms of its characteristics and COS production potential with maximum relative yield (31%). Results revealed that Bacillus chitosanases could be used directly for efficient bioconversion of chitosan into COS and will be valuable for large-scale production of biologically active COS., (© 2022 Wiley-VCH GmbH.)

Creation of new two-dimensional (2D) architectures has attracted significant attention in the field of self-assembly for structural diversity and new functionalization. Although numerous 2D polymer nanosheets have been reported, 2D nanosheets with tubular channels have been unexplored. Herein, we describe a new strategy for the fabrication of stimulus-responsive conjugated polymer 2D nanosheets with hollow cavities. Amphiphilic macrocyclic diacetylenes self-assembled in an aqueous solution in a columnar manner to afford bilayered 2D nanosheets with intrinsically tubular nanochannels. UV-induced polymerization resulted in the generation of blue-colored tubular conjugated polydiacetylene 2D nanosheets. Immobilization of gold nanoparticles, fluorescence labeling with FRET phenomenon and colorimetric DNA sensing were demonstrated with these new 2D nanosheets. In addition, the free NH 2 containing polymerized 2D nanosheet was utilized for conductivity behavior and grafting on graphene oxide (GO)., (© 2022 Wiley-VCH GmbH.)

This study involves evaluation of two native cyanobacterial strains Euryhalinema and Desertifilum isolated from a mangrove pond in Haikou (China) for their possible phycocyanin (C-PC) production. Maximal growth rate with highest chlorophyll and C-PC accumulation were observed at 28°C and 60 μmol photons m -2 s -1 photon flux density for Euryhalinema sp., while for Desertifilum sp. at 32°C and 80 μmol photons m -2 s -1 . Nitrogen and iron concentration trails revealed that double strength concentration of sodium nitrate and ferric ammonium citrate in original BG11 media increased growth rate and accumulation of C-PC for both strains. Three different C-PC extraction methods were tested. The combined extraction protocol of freeze-thaw and ultrasonication markedly increased the C-PC extraction efficiency and attained the food grade purity ( A 620 / A 280 ratio >0.7), whereas a higher C-PC yield was found with Na-phosphate buffer. Furthermore, the clarified crude extract was used to purify C-PC by fractional ammonium sulfate [(NH₄)₂SO₄] precipitation, Sephadex G-25 gel filtration chromatography, and DEAE-sephadex ion exchange chromatography and attained analytical grade purity ( A 620 / A 280 ratio >3.9). Taken together, both strains showed their potential to be domesticated for valuable phycocyanin production., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Khazi, Li, Liaqat, Malec, Li and Fu.)

Although Haematococcus lacustris has been developed for astaxanthin production for decades, the production cost is still high. In order to modify the production processes, we proposed a novel strategy of cultivation, featured by sequential indoor continuous mixotrophic cultivation for the production of green cells followed by outdoor phototrophic induction for astaxanthin accumulation. The continuous mixotrophic cultivation was first optimized indoor, and then the seed culture of mixotrophic cultivation was inoculated into outdoor open raceway ponds for photoinduction. The results showed that mixotrophically grown cultures could efficiently grow without losing their photosynthetic efficiency and yielded higher biomass concentration (0.655 g L -1 ) and astaxanthin content (2.2% DW), compared to phototrophically grown seed culture controls. This novel strategy might be a promising alternative to the current approaches to advance the production technology of astaxanthin from microalgae., Competing Interests: MIK and FL are currently employed by Panzhihua Gesala Biotechnology Inc., Panzhihua, China, and JL is the major shareholder of the company. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Khazi, Shi, Liaqat, Yang, Li, Yang and Li.)

Supramolecular gels originating from the hierarchical self-assembly of low molecular weight organic molecules is a strongly emerging field of advanced material research for the fabrication of soft functional materials. Herein, a novel supramolecular gel was fabricated through the protonation-triggered unidirectional self-assembly of pyridine-attached macrocyclic diacetylene ( PyMCDA ). Basic nitrogen of a pyridine ring with a strong affinity toward proton transforms the neutral PyMCDA into gelator in its protonated pyridinium salt form ( PyMCDA-H + ), which further evolves to nano-fibrillar networks to yield a supramolecular gel. Under the irradiation of UV light, the white color gel turned to a robust covalently cross-linked blue-phase PDA gel. Interestingly, polymeric PyMCPDA-H + gel exhibits a naked-eye detectable reversible blue-red colorimetric response for alternating acid/base (H 2 SO 4 /NH 4 OH) and colorimetric sensitivity toward selected anions: CH 3 COO - , CN - , HCOO - , and CH 3 CH 2 COO - . It is with the hope that this work point toward the utility and versatility of macrocyclic PDAs for constructing chromogenic supramolecular gels for their possible use in sensing systems.

The cooperative non-covalent interactions arising from structurally integrated multiple molecules have emerged as a powerful tool for the creation of functional supramolecular structures. Herein, we constructed cyclic dipeptide (CDP)-polydiacetylene (PDA) conjugate (CDP-DA) by introducing cyclo(l-Phe-l-Lys) to the linear 10,12-pentacosadiynoic acid. Owing to extensive hydrogen bonding characteristics, together with structural chirality of cyclo(l-Phe-l-Lys) and strong π-π stacking diacetylenic template, CDP-DA generated supramolecular nanotubes. The structural visualization using scanning and transmission electron microscopy revealed chloroform/methanol co-solvent polarity tuned morphological transformation of intrinsic lamellar assemblies into nanotubes comprising single-wall and multi-wall structure. The mechanistic understanding by X-ray diffraction patterns confirms bilayer organization in lamellar structure, which forms nanotubes via a gradual lamellar curling-to-scrolling process. The supramolecular CDP-DA nanotubes are transformed into the rigid covalently cross-linked blue-phase polydiacetylene (CDP-PDA) by UV irradiation. Very interestingly, the blue-phase nanotubes display reversible thermochromic changing temperature up to 150 °C with excellent repeatability over a dozen thermal cycles. This work provides an efficient strategy for precise morphological control and aiding the perspective for development in nanostructures for functional devices., Competing Interests: The authors declare no competing financial interest., (This journal is © The Royal Society of Chemistry.)

Phycocyanin is a blue-colored pigment-protein complex that exhibits numerous biofunctions such as anti-inflammation, antioxidation, antitumor, neuroprotective effect, and immunological enhancement. Purified phycocyanin has pharmaceutical and nutraceutical applications. In addition, as a nontoxic and non-carcinogenic natural coloring agent, phycocyanin has many applications in the food and cosmetic industries. This chapter describes a protocol for extraction and analytical grade purification of phycocyanin from cyanobacteria. The purification steps include (1) extraction of phycocyanin from biomass, (2) ammonium sulfate precipitation of phycocyanin and dialysis, and (3) purification of phycocyanin by gel filtration and ion-exchange chromatography.

The cation-directed self-assembly process has emerged as a fascinating approach for constructing supramolecular architectures and manifested a diverse range of assembly related applications. Herein, we synthesized a macrocyclic structure containing bis-amidopyridine and photopolymerizable diacetylene template, PyMCDA. Owing to the metal coordination affinity of bis-amidopyridine and the π-π stacking characteristic of diacetylene template and complementary to the cyclic molecular framework, Cs + -directed organic nanotubes are generated via unidirectional self-assembly of PyMCDA. The monomeric PyMCDA nanotubes are transformed into the covalently cross-linked chromogenic polydiacetylene nanotubes (PyMCPDA-Cs + ) by UV-promoted topochemical polymerization. The result of a metal-ligand coordination characteristic, geometric parameters in solid-state assemblies, and topochemical polymerization behavior reveals a generation of Cs + ion inserted nanotubes. Interestingly, PyMCDA-Cs + nanotubes display thermochromic property with a brilliant blue-to-red color transition.

Owing to their capability of forming extensive hydrogen bondings and the facile introduction of chirality, cyclic dipeptides (CDPs) have gained great attention as scaffolds for functional supramolecules. Surprisingly, introduction of a photopolymerizable diacetylene (DA) moiety to the CDP afforded nanotubular structures with enhanced stability and reversible thermochromism. A series of CDP-containing DAs (CDP-DAs) are prepared by coupling 10,12-pentacosadiynoic acid with CDPs, cyclo(-Gly-Ser) and cis/trans cyclo(-Ser-Ser). Fabrication of CDP-DA self-assemblies in a polar chloroform and methanol solvent mixture affords nanotubes comprising single-wall and multiwall structures. The self-assembly behavior and morphology characteristic are examined by scanning electron microscopy and transmission electron microscopy. Next, X-ray diffraction analysis confirms well-ordered lamellar structures with a perfect agreement with the bilayer formation leading to the tubular structure via lamellar scrolling behavior. Upon UV irradiation, monomeric CDP-DA tubular assemblies result in the blue-colored CDP/polydiacetylene (PDA) nanotubes. Interestingly, CDP/PDA nanotubes exhibit a reversible blue-to-red color change for over 10 consecutive thermal cycles. The CDP-DA/PDA supramolecular system demonstrates potential applications in developing stimulus-responsive functional materials.

"Paper" has greatly contributed to the development and spread of civilization. Even in today's "digitalized" world, paper continues to play a key role in socioeconomic growth, as is evidenced by the growth in global paper consumption. Unfortunately, the use of paper has its cost in terms of the exhaustion of world's natural resources. Consequently, new, cost-effective technologies that preserve natural resources are required for this purpose. Functional materials have revolutionized the way people think about developing new technologies. Especially important in this regard are "smart reactive materials," which are capable of actively responding to external stimuli such as heat, light, mechanical stress, and specific molecular orientations. Moreover, functionalized chromogenic materials, which undergo reversible color switching upon external stimulation, have attracted great attention in the context of developing rewritable paper. Here, investigations of various materials and systems that are devised for use as rewritable paper are reviewed with the hope that the coverage will stimulate and guide future studies in this area., (© 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Response surface methodology (RSM) based on the 2 3 factorial central composite design (CCD) was employed to evaluate optimum culture conditions (temperature, light irradiance and agitation) to enhance biomass and phycocyanin content of Spirulina platensis . The predicted maximum biomass and phycocyanin content by RSM was 1.06 g L -1 and 107 mg L -1 , respectively, whereas maximum biomass and phycocyanin content of 1.32 g L -1 and 127 mg L -1 was obtained in the validation experiments under optimized conditions after 10 days of cultivation. Further, influence of optimized conditions (temperature 33±2 ºC, light irradiance 44 μmol photons m -2  s -1  and a flow rate of 2.5 L min -1 ) on growth and phycocyanin content of S. platensis in 7L Panel photobioreactor (PPBR) cultivation was investigated. A 15 days production was carried out and it was observed that a maximum biomass yield of 2.42 g L -1 with a specific growth rate 0.202 day -1 and phycocyanin content of 228 mg L -1 was obtained in the PPBR. The optimum culture conditions obtained through response surface methodology were successfully determined to maximize the biomass and phycocyanin.

A novel series of 5-(2-alkyl/aryl-6-arylimidazo[2,1-b][1,3,4]thiadiazol-5-yl)methylene-1,3-thiazolidinediones were synthesized as possible PPARγ agonists. The structures of these target molecules were established by spectral and analytical data. All the newly synthesized compounds were screened for their in vivo hypoglycaemic and hypolipidemic activity in male Wistar rats. Further, compounds with good activity were screened for PPARγ agonist activity. Among the screened compounds, 5-{[2-Cyclohexyl-6-(4-methoxyphenyl)imidazo[2,1-b] [1,3,4]thiadiazol-5-yl]methylene}-1,3-thiazolidine-2,4-dione (3i) exhibits promising hypoglycaemic and hypolipidemic activity via potential PPARγ agonist activity., (© 2013 John Wiley & Sons A/S.)

In the title compound, C(7)H(7)ClN(4)O, the pyrazolo-pyrimidine ring is essentially planar, the r.m.s. deviation of the fitted atoms being 0.0071 Å. The crystal structure features strong N-H⋯O hydrogen bonds and further consolidated by weak C-H⋯O, C-H⋯N and C-H⋯Cl inter-actions.

Fused triazolothienopyrimidines were prepared from the corresponding 2-amino-4,5,6,7-tetrahydrobenzo[b]thiophene-3-carbonitrile. These precursors were intern prepared by employing the Gewald's reaction. All the newly synthesized compounds were characterized by spectral and analytical data. Title compounds displayed promising antibacterial and antifungal activities. Compound 3h which exhibited good antimicrobial activity was incorporated into SLN and characterized for particle size, entrapment efficiency (EE%), scanning electron microscopy (SEM), differential scanning calorimetry (DSC) and in-vitro release studies. It showed narrow particle size distribution with high entrapment efficiency. In-vitro release study of compound loaded SLNs in phosphate buffer of pH 7.4, exhibited a biphasic pattern with an initial burst and prolonged release over 24 h., (Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)