Preparative Biochemistry & Biotechnology最新文献

Ixabepilone (IXA) is an FDA-approved chemotherapeutic agent for metastatic breast cancer; however, its clinical use is limited by severe toxicity to healthy tissues. To improve its therapeutic index, tumor-targeted drug delivery systems are required. In this study, IXA was encapsulated for the first time into folic acid (FA)-functionalized biopolymeric nanoparticles (NPs) to promote preferential delivery to folate receptor (FR)-expressing breast cancer cells. Chitosan (CS) and alginate (ALG) were conjugated with FA to fabricate targeted NP systems, and IXA-loaded formulations were optimized in terms of encapsulation efficiency and particle size. The optimized IXA/FACS and IXA/FAALG NPs exhibited encapsulation efficiencies of 51.3 ± 4.6% and 47.6 ± 5.0%, with mean particle sizes of approximately 155 nm. In vitro release studies under physiological and tumor-mimicking pH conditions demonstrated pH-responsive behavior, with increased IXA release at acidic pH (5.5). Release kinetics analysis indicated diffusion-controlled and anomalous transport mechanisms according to the Higuchi and Korsmeyer-Peppas models. Cytotoxicity studies on MDA-MB-231 and MCF-7 breast cancer cell lines revealed enhanced cytotoxic effects of FA-conjugated IXA-loaded NPs in FR-positive MDA-MB-231 cells compared to MCF-7 cells, suggesting preferential FR-mediated cellular interaction. Overall, FA-functionalized CS and ALG NPs represent a promising in vitro platform for targeted IXA delivery in FR-expressing breast cancer therapy.

Selenopolysaccharides exhibit potent antioxidant, immunomodulatory and anticancer properties enhancing their biological effectiveness compared to non-selenium variants. Their therapeutic potential in oxidative stress-related disorders is highlighted by improved bioavailability and biocompatibility. This review evaluates selenopolysaccharide research, aiming to resolve issues related to extraction methods, structural characterization and mechanisms that limit their development. Key objectives include analyzing extraction techniques, structural characteristics, biological activities, mechanisms of action and challenges related to clinical applications. In this review, we highlighted the use of various extraction methods and employed spectroscopic and chromatographic analyses. Findings show that microwave-assisted chemical selenylation and nanoparticle synthesis enhance selenium incorporation and bioactivity. Advanced structural analyses revealed diverse selenium valence states affecting functional outcomes. Selenopolysaccharides have potent effects via the MAPK, NF-κB, and TLR signaling pathways, demonstrating synergistic interactions between selenium and polysaccharides. Despite better bioavailability and lower toxicity compared to inorganic selenium, variability in composition and lack of clinical validation hinder their potential. To fully leverage selenopolysaccharides as functional food ingredients and pharmacological agents, it is essential to optimize extraction, elucidate their structures and understand their mechanisms, while addressing concerns regarding standardization, safety and efficacy for their use in managing inflammation, cancer and metabolic disorders.

Microalgae offer a sustainable and adaptable source of essential vitamins, making them a promising alternative to traditional synthetic and plant-based sources. As natural and bioavailable nutrients become increasingly important, microalgae such as Chlorella, Spirulina, Dunaliella, and Haematococcus, known for their ability to synthesize a wide range of vitamins, including A, B, C, D, E, and K, are gaining more attention. The biosynthesis pathways of these vitamins are explored, with a focus on stress-induced techniques and the impact of genetic engineering on production yields. Recent innovations in photobioreactors and hybrid open-closed systems, as well as advanced extraction methods, are explored for their potential to enhance efficiency and sustainability in vitamin recovery. Their antioxidant, anti-inflammatory, and immune-boosting properties make microalgal vitamins valuable tools for addressing global nutritional deficiencies and improving overall health. Despite significant progress, challenges persist, including high production costs, scalability issues, and regulatory concerns. The review emphasizes the importance of developing cost-effective farming systems, advanced genetic engineering, and modern extraction technologies, and suggests directions for future research. Vitamins from microalgae hold great potential for transforming the global nutraceutical and pharmaceutical industries, fostering innovation, creating revenue opportunities, and promoting a more sustainable and eco-friendly future.

Natural pigments, derived from plants, animals, and microorganisms, offer numerous health benefits, including antioxidant, anticancer, and antimicrobial properties. Microbial sources, in particular, provide scalable, eco-friendly alternatives. However, production faces challenges such as low yield, high cultivation costs, and limited color diversity. Recent biotechnological advances-such as metabolic engineering, omics technologies, CRISPR/Cas9 genome editing, and synthetic biology-are addressing these hurdles by enhancing pigment biosynthesis and expanding pigment varieties. These innovations facilitate industrial-scale production while reducing environmental impact. Natural pigments now find applications in food, cosmetics, pharmaceuticals, and textiles, often replacing synthetic dyes. Continued interdisciplinary research and industrial collaboration are essential to overcome production constraints and meet market demand. This review aims to provide a comprehensive and critical synthesis of natural pigments derived from plant, animal, and microbial sources, with a particular focus on recent advances in sustainable extraction technologies and biotechnological innovations such as metabolic engineering, CRISPR/Cas9, and synthetic biology. It systematically compares the advantages and limitations of pigments from different biological origins and evaluates their expanding applications in the food, pharmaceutical, nutraceutical, and biomedical sectors. Furthermore, the review identifies key challenges in scaling production and proposes future research directions to facilitate the transition from laboratory-scale discoveries to industrial applications.

The effect of different solvent extractions on the metabolome of the diatom Halamphora sp. and their correlation with 2,2-diphenyl-1-picrylhydrazyl (DPPH) and nitric oxide (NO) free radical scavenging activities were investigated using proton nuclear magnetic resonance (¹H NMR)-based metabolomics. Evaluation of the DPPH and NO scavenging activities of Halamphora sp. extracted with methanol, ethanol, acetone, chloroform or hexane revealed that the acetone and chloroform extracts exhibited the highest activities, with DPPH scavenging of 44.7% and NO scavenging of 107.5%, respectively. In total, 30 metabolites were putatively identified including amino acids, fatty acids, sugars, phenolics, carotenoids and pigments. According to the partial least square model, metabolites contributing to the observed bioactivities included valine, alanine, leucine, linoleic acid, palmitic acid, sucrose, glucose, astaxanthin, canthaxanthin, lutein, zeaxanthin, violaxanthin, fucoxanthin, fucoxanthinol, choline and cholesterol. These findings demonstrate that the acetone and chloroform extracts of Halamphora sp. can serve as source of bioactive metabolites with antioxidant potential. Moreover, the present ¹H NMR metabolomics approach proved to be a valuable tool for metabolites identification in microalgae, further supporting the potential of Halamphora sp. as a sustainable and nutritionally rich source for aquafeed applications.

L-Glutaminase (EC 3.5.1.2) is an industrially and therapeutically relevant enzyme that hydrolyzes L-glutamine to L-glutamic acid and ammonia. In this study, a potent L-glutaminase-producing bacterium, Klebsiella pneumoniae strain SCPRC, was isolated from soil samples in Kerala, India, using Minimal Glutamine Agar medium with phenol red indicator. The strain was identified by biochemical characterization and 16S rRNA sequencing (GenBank Accession No. OQ338363). Under unoptimized conditions, enzyme activity was 67.18 U/mL. Optimization of culture parameters using Response Surface Methodology with Central Composite Design (RSM-CCD) identified ammonium sulfate, K₂HPO₄, and incubation time as critical factors. The optimized conditions yielded 131.77 U/mL, representing a nearly two-fold improvement compared to baseline production. ANOVA confirmed the model's significance (p < 0.01) with a non-significant lack of fit. These findings establish K. pneumoniae SCPRC as a novel source of L-glutaminase and demonstrate the utility of statistical optimization for enhancing enzyme yields, supporting its potential application in therapeutic and food biotechnology.

In this study, iron nanoparticles (YBFeNPs) were green-synthesized using the aqueous extract (YB-E) of wild cherry laurel (Prunus laurocerasus L.) fruit to evaluate their potential applications in food safety. The synthesized YBFeNPs were investigated through Fourier-transform infrared spectroscopy, X-ray diffraction, scanning electron microscopy, transmission electron microscopy, and energy-dispersive X-ray spectroscopy analyses. YBFeNPs showed higher total phenolic content, total flavonoid content, and total antioxidant capacity compared to the original extract, suggesting that plant metabolites enhance NP bioactivity. Antioxidant capacity was further validated by DPPH, ABTS, and FRAP assays, which demonstrated strong radical scavenging and reducing power. The antibacterial activity of YBFeNPs was assessed against Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, and Enterococcus faecalis, revealing concentration-dependent effects with the highest inhibition zone of 14.5 ± 0.4 mm for E. coli. The chemical composition of the YB-E extract was analyzed using liquid chromatography-tandem mass spectrometry, identifying quinic acid, a polyol, and phenolic compounds such as chlorogenic acid (1.45 mg/g) and naringenin (0.02 mg/g). Additionally, the adsorption capacities of YBFeNPs were investigated against patulin and hydroxymethylfurfural (HMF), toxic compounds posing significant threats to food safety. The NPs demonstrated effective adsorption of both patulin and HMF, achieving maximum adsorption rates of 61.05% and 46.12%, respectively, at a concentration of 5.0 g/L after 240 min.

Sideritis lanata ("mountain tea") is widely consumed; however, its water-extractable chemotype and associated biological activities remain underdefined. In this study, an ultrasound-assisted aqueous extract was characterized to link chemical composition with biological function. The extract exhibited a moderate phenolic load, with a total phenolic content (TPC) of 22.27 mg gallic acid equivalents per gram (GAEs/g) and a total flavonoid content (TFC) of 7.50 mg rutin equivalents per gram (REs/g). Phenolic profiling by liquid chromatography-electrospray ionization-tandem mass spectrometry (LC-ESI-MS/MS) revealed a phenolic-acid-dominated signature, mainly hydroxycinnamic acids led by chlorogenic acid (691 µg/g), followed by caffeic acid (231 µg/g), p-coumaric acid (211 µg/g), and ferulic acid (50.4 µg/g), together with abundant hydroxybenzoic acids such as 3- and 4-hydroxybenzoic acids (188 and 183 µg/g, respectively). Antioxidant activity, evaluated using six complementary assays, was moderate and assay-dependent, with stronger metal-chelating activity (IC₅₀ = 1.31 mg/mL) and ferric reducing antioxidant power (FRAP; EC₅₀ = 1.38 mg/mL), followed by phosphomolybdenum (EC₅₀ = 2.03 mg/mL), and weaker cupric reducing antioxidant capacity (CUPRAC; EC₅₀ = 3.10 mg/mL), ABTS (IC₅₀ = 3.64 mg/mL), and DPPH (IC₅₀ = 5.13 mg/mL). The extract inhibited acetyl- and butyrylcholinesterase and tyrosinase with comparable potency (2.69, 2.53, and 2.64 mg/mL, respectively), while weaker inhibition was observed for α-glucosidase (10.63 mg/mL) and α-amylase (19.93 mg/mL). In A549 lung carcinoma cells, viability decreased concentration-dependently; at the half-maximal inhibitory concentration (IC₅₀), tumor necrosis factor-alpha (TNF-α) increased to 26.73 ng/mL, whereas transforming growth factor-beta (TGF-β) and interleukin-1 beta (IL-1β) decreased to 9.4 and 10.83 pg/mL, respectively, while at ½ × IC₅₀ TNF-α was 1.3 ng/mL and TGF-β reached 46.6 pg/mL. Overall, this hydroxycinnamate- and hydroxybenzoate-rich aqueous extract exhibits moderate, target-selective antioxidant and enzyme-inhibitory activities together with dose-dependent immunomodulatory effects.

The toxicity of lignocellulosic hydrolysate has long plagued the alcoholic fermentation industry, whereas elevating dissolved oxygen concentrations can effectively enhance microbial tolerance and fermentation efficiency. This study further elucidates the rapid sugar metabolism mechanism of Candida glycerinogenes under aerobic conditions by examining its carbon flux allocation and sugar metabolic rates. C. glycerinogenes has an excellent performance on glycolytic rate and ethanol productivity compared to Saccharomyces cerevisiae under aerobic conditions. Unlike S. cerevisiae W303, C. glycerinogenes had an increasing NADH/NAD⁺ ratio and maintained high activities of glycolytic enzymes at high ATP levels. The maximum inhibitory effect of ATP on the relative activities of hexokinase (HXK), phosphofructose kinase (PFK), and pyruvate kinase (PYK) in S. cerevisiae W303 was 2.69, 1.35, and 1.41 fold that of C. glycerinogenes, respectively. Overexpression of PFK1 from C. glycerinogenes in S. cerevisiae W303 could increase the glycolytic rate, increasing the maximum glucose consumption rate by 14.48%. The high activities of glycolytic enzymes and their insensitivity to ATP inhibition may be key and prerequisite factors for the rapid fermentation of C. glycerinogenes. These results help understand the rapid fermentation from the perspectives of NAD(H) and ATP regulation, and provide new insights into the production of ethanol and other glycolytic products.

The present study has investigated the interactions of the phytochemicals present in sugarcane bagasse (SCB) with alcohol dehydrogenase (ADH1) enzyme in Saccharomyces cerevisiae using molecular simulations. ADH1 catalyzes the reduction of acetaldehyde to ethanol. The metabolic hindrance induced by phytochemicals can adversely affect kinetics and yield of ethanol fermentation. The phytochemicals in SCB biomass were detected using LC-ESI-MS/QTOF analysis after dilute acid/alkali pretreatment and extraction using methanol and acetonitrile. Molecular docking simulation revealed high binding affinity of four phytochemicals for ADH1 enzyme due to low binding energies and inhibition constants: chlorogenic acid (-8.64 kcal/mol, 0.464 μM), apigenin (-7.72 kcal/mol, 2.2 μM), diosmetin (-7.47 kcal/mol, 3.37 μM), and caffeic acid (-7.03 kcal/mol, 7.07 μM). The molecular dynamics simulations showed that root mean square deviation (RMSD) values of the complexes of chlorogenic acid (0.22 nm) and apigenin (0.27 nm) were significantly smaller than apoprotein (0.37 nm), which indicates their stability. The root mean square fluctuation (RMSF) value of active site residues of the phytochemical complexes (chlorogenic acid = 0.15 nm, apigenin = 0.13 nm) was also smaller than that of apoprotein (0.17 nm). These results clearly indicate that phytochemicals can hinder metabolic pathway of S. cerevisiae due to preferential binding to ADH1.