Effects of p-coumaric acid on probiotic properties of Lactobacillus acidophilus LA-5 and lacticaseibacillus rhamnosus GG

Probiotics are defined as "live microorganisms that provide health benefits to the host when administered in adequate amounts." Probiotics have beneficial effects on human health, including antibacterial activity against intestinal pathogens, regulation of blood cholesterol levels, reduction of colitis and inflammation incidence, regulation of the immune system, and prevention of colon cancer. In addition to probiotic bacteria, some phenolic compounds found in foods we consume (both food and beverages) have positive effects on human health. p-coumaric acid (p-CA) is one of the most abundant phenolic compounds in nature and human diet. The interactions between these two different food components (phenolics and probiotics), resulting in more beneficial combinations called synbiotics, are not well understood in terms of how they will affect the gut microbiota by promoting the probiotic properties and growth of probiotic bacteria. Thus, this study aimed to investigate synbiotic relationship between p-CA and Lactobacillus acidophilus LA-5 (LA-5), Lacticaseibacillus rhamnosus GG (LGG). Probiotic bacteria were grown in the presence of p-CA at different concentrations, and the effects of p-CA on probiotic properties, as well as its in vitro effects on AChE and BChE activities, were investigated. Additionally, Surface analysis was conducted using FTIR. The results showed that treatment with p-CA at different concentrations did not exhibit any inhibitory effect on the growth kinetics of LA-5 and LGG probiotic bacteria. Additionally, both probiotic bacteria demonstrated high levels of antibacterial properties. It showed that it increased the auto-aggregation of both probiotics. While p-CA increased co-aggregation of LA-5 and LGG against Escherichia coli, it decreased co-aggregation against Staphylococcus aureus. Probiotics grown with p-CA were more resistant to pepsin. While p-CA increased the resistance of LA-5 to bile salt, it decreased the resistance of LGG. The combinations of bacteria and p-CA efficiently suppressed AChE and BChE with inhibition (%) 11.04-68.43 and 13.20-65.72, respectively. Furthermore, surface analysis was conducted using FTIR to investigate the interaction of p-coumaric acid with LA-5 and LGG, and changes in cell components on the bacterial surface were analyzed. The results, recorded in range of 4000 -600 cm-1 with resolution of 4 cm-1, demonstrated that p-CA significantly affected only the phosphate/CH ratio for both bacteria. These results indicate the addition of p-CA to the probiotic growth may enhance the probiotic properties of bacteria.

Involvement of NLRP3 inflammasome pathway in the protective mechanisms of ferulic acid and p-coumaric acid in LPS-induced sickness behavior and neuroinflammation in mice

Ferulic acid (FA) and p-coumaric acid (PCA) are abundantly present in commonly consumed food and beverages. Being polyphenolic compounds, they have been explored for their antioxidant and anti-inflammatory properties. Based on our previous study, we selected these two compounds to further investigate their potential in lipopolysaccharide (LPS)-induced sickness behavior and the ensuing neuroinflammation by specifically focusing on the NLRP3 inflammasome pathway. Male Swiss albino mice were divided into nine groups (n = 6) consisting of Normal Control, LPS, fluoxetine (FLX), FA40, FA160, FA640, PCA40, PCA160, and PCA640 respectively. Each group received respective FA or PCA treatment except Normal Control and LPS, which received the vehicle, carboxymethylcellulose 0.25% w/v. All groups were challenged with LPS 1.5 mg/kg, intraperitoneally except the Normal Control group, which received saline. Behavioral assessments were performed between 1-2 h, and the whole brains were collected at 3 h post-LPS administration. LPS-induced sickness behavior was characterized by significantly reduced spontaneous activity and high immobility time. The expression of NLRP3, ASC, caspase-1 and IL-1β was significantly increased, along with the levels of brain IL-1β suggesting the assembly and activation of NLRP3 inflammasome pathway. Furthermore, the major cytokines involved in sickness behavior, IL-6 and TNF-α were also significantly elevated with the accompanied lipid peroxidation. The results of this study emphasize that within the employed dose ranges of both FA and PCA, both the compounds were effective at blocking the activation of the NLRP3 inflammasome pathway and thereby reducing the release of IL-1β and the sickness behavior symptoms. There was a prominent effect on cytokine levels and lipid peroxidation as well.

A nano-liposomal carrier containing p-coumaric acid for induction of targeted apoptosis on melanoma cells and kinetic modeling

There has been a growth in the use of plant compounds as biological products for the prevention and treatment of various diseases, including cancer. As a phenolic compound, p-Coumaric acid (p-CA) demonstrates preferrable biological effects such as anti-cancer activities. A nano-liposomal carrier containing p-CA was designed to increase the anticancer effectiveness of this compound on melanoma cells (A375). To determine the characteristics of synthesized liposomes, encapsulation efficiency was measured. In addition, the particle size was measured utilizing DLS, FTIR, and morphology examination using SEM. In vitro release was also studied through the dialysis method, while toxicity was evaluated using the MTT assay. To determine apoptotic characteristics, biotechnology tools like flow cytometry, real time PCR, and atomic force microscopy (AFM) were employed. The findings indicated that in the cells treated with the liposomal form of p-CA, the amount of elastic modulus was higher compared to its free form. Kinetic modeling indicated that the best fitting model was zero-order.

Hepatoprotective effect of p-Coumaric acid against KBrO3 -induced apoptosis in HepG2 cells

In the present study, we investigated the effect of the p-Coumaric acid (PCA), a phenolic acid, on potassium bromate (KBrO3 ) induced oxidative damage, Ras/Raf/MEK signaling, and apoptosis in HepG2 cells. Our findings showed that PCA-treated cells prevented cytotoxicity compared with KBrO3- treated cells. Furthermore, KBrO3 -induced oxidative stress and lipid peroxidation was attenuated by PCA and it also increased the antioxidant levels such as SOD, CAT, and GPX. Additionally, PCA inhibited the KBrO3 -induced DNA damage in HepG2 cells. Moreover, PCA treatment suppressed the activation of Ras/Raf/MEK signaling and increased the expression of PRDX-1. In addition, PCA prevented the KBrO3 -induced apoptosis cascade by altering the expression of proapoptotic, Bax, caspase-3, and antiapoptotic, Bcl-2 proteins. The present study proves that PCA inhibited the KBrO3 -induced oxidative stress, DNA damage, and apoptotic signaling cascade in HepG2 cells.

p-Coumaric acid attenuates the effects of Aβ42 in vitro and in a Drosophila Alzheimer's disease model

Alzheimer's disease (AD) is the most common neurodegenerative condition in civilizations worldwide. The distinctive occurrence of amyloid-beta (Aβ) accumulation into insoluble fibrils is part of the disease pathophysiology with Aβ42 being the most toxic and aggressive Aβ species. The polyphenol, p-Coumaric acid (pCA), has been known to boost a number of therapeutic benefits. Here, pCA's potential to counteract the negative effects of Aβ42 was investigated. First, pCA was confirmed to reduce Aβ42 fibrillation using an in vitro activity assay. The compound was next examined on Aβ42-exposed PC12 neuronal cells and was found to significantly decrease Aβ42-induced cell mortality. pCA was then examined using an AD Drosophila melanogaster model. Feeding of pCA partially reversed the rough eye phenotype, significantly lengthened AD Drosophila's lifespan, and significantly enhanced the majority of the AD Drosophila's mobility in a sex-dependent manner. The findings of this study suggest that pCA may have therapeutic benefits for AD.

Effect of nisin and p-coumaric acid on autoinducer-2 activity, biofilm formation, and sprE expression of Enterococcus faecalis

Quorum sensing (QS) is an inter- and intracellular communication mechanism that regulates gene expression in response to population size. Autoinducer-2 (AI-2) signaling is a QS signaling molecule common to both Gram-negative and Gram-positive bacteria. Enterococcus faecalis is one of the leading causes of nosocomial infections worldwide. There has been an increasing interest in controlling infectious diseases through targeting the QS mechanism using natural compounds. This study aimed to investigate the effect of nisin and p-coumaric acid (pCA), on biofilm formation and AI-2 signaling in E. faecalis. Their effect on the expression of the QS-regulated virulence encoding gene sprE was also investigated. Nisin exhibited a MIC ranging from 0.25 to 0.5 mg/mL, while the MIC of pCA was 1 mg/mL. The luminescence-based response of the reporter strain Vibrio harveyi BB170 was used to determine AI-2 activity in E. faecalis strains. Nisin was not effective in inhibiting AI-2 activity, while pCA reduced AI-2 activity by ≥ 60%. Moreover, pCA and nisin combination showed higher inhibitory effect on biofilm formation of E. faecalis, compared to the treatment of pCA or nisin alone. qRT-PCR analysis showed that nisin alone and the combination of nisin and pCA, at their MIC values, led to a 32.78- and 40.22-fold decrease in sprE gene expression, respectively, while pCA alone did not have a significant effect. Considering the demand to explore new therapeutic avenues for infectious bacteria, this study was the first to report that pCA can act like a quorum sensing inhibitor (QSI) against AI-2 signaling in E. faecalis.

The bound polyphenols of foxtail millet (Setaria italica) inner shell inhibit breast cancer by promoting lipid accumulation-induced autophagic death

Foxtail millet is a traditional excellent crop with high nutritional value in the world, belong to cereals. The bran of foxtail millet is rich in polyphenol that has antioxidant, anti-inflammatory, and anti-tumorigenic effects. Previously, we extracted bound polyphenols from the inner shell of foxtail millet bran (BPIS). Here, we report that BPIS specifically induced breast cancer cell death and elevated the autophagy level simultaneously. The addition of an autophagy inhibitor blocked BPIS-induced breast cancer cell death, indicating that excessive autophagy induced cell death. Furthermore, oil red O and BODIPY staining also confirmed that lipids, which are important inducers of autophagy, accumulated in breast cancer cells treated with BPIS. Lipidomics research revealed that glycerophospholipids were the main accumulated lipids induced by BPIS. Further study showed that elevated PCYT1A expression was responsible for glycerophospholipid accumulation, and BPIS contained ferulic acid and p-coumaric acid, which induced PCYT1A expression and breast cancer cell death. Collectively, our results revealed that BPIS resulted in autophagic death by enhancing lipid accumulation in breast cancer cells, and BPIS contains ferulic acid and p-coumaric acid, which provided new insights into developing nutraceuticals and drugs for breast cancer patients.

The protective effect of p-Coumaric acid on hepatic injury caused by particulate matter in the rat and determining the role of long noncoding RNAs MEG3 and HOTAIR

Increasing air pollution is associated with serious human health problems. P-coumaric acid (PC) is a herbal phenolic compound that exhibits beneficial pharmacological potentials. Here, the protective effect of PC on liver injury induced by air pollution was examined. Thirty-two adult male Wistar rats (200-250 g) were divided randomly into four groups (n = 8). The groups were; Control (rats received DMSO and then exposed to clean air), PC (rats received PC and then exposed to clean air), DMSO + Dust (rats received DMSO and then exposed to dust), and PC + Dust (the animals received PC and then exposed to dust). The clean air, DMSO, PC, and dust were administrated 3 days a week for 6 consecutive weeks. The rats were anesthetized and their blood samples and liver sections were taken to conduct molecular, biomedical, and histopathological tests. Dust exposure increased the liver enzymes, bilirubin, triglyceride, cholesterol, and the production of liver malondialdehyde, and decreased in liver total anti-oxidant capacity and serum high-density lipoprotein. It also increased the mRNA expression of inflammatory-related cytokines, decreased the mRNA expression of SIRT-1, decreased the expression levels of miR-20b5p, and MEG3 while increased the expression levels of miR-34a, and HOTAIR. Dust exposure also increased the liver content of three cytokines TNF-α, NF-κB, HMGB-1, and ATG-7 proteins. PC enhanced liver function against adverse effects of dust through recovering almost all the studied variables. Exposure to dust damaged the liver through induction of oxidative stress, inflammation, and autophagy. PC protected the liver against dust-induced cytotoxicity.

Response Surface Methodology-based Optimized Ultrasonic-assisted Extraction and Characterization of Selected High-Value Components from Gemlik Olive Fruit

This article presents an optimized ultrasound-assisted ethanolic extraction (UAEE) and characterization of selected high-value components from Gemlik olive fruit (GOF) harvested from Potohar region of Pakistan. Response surface methodology (RSM), involving central composite design (CCD), was applied to optimize the extraction variables i.e., temperature (25-65 °C), extraction time (15-45 min) and aqueous ethanol concentration (60-90%) for optimal recovery of bioactives extract, total phenolic contents (TPC) and DPPH free radical scavengers. Under the optimized set of conditions such as 43 °C temperature, 32 min extraction time and 80 % aqueous ethanol, the best extract yield (218.82 mg/g), TPC (19.87 mg GAE/g) and DPPH scavenging activity (63.04 %) were recorded. A quadratic polynomial model was found to be reasonably fitted to the observed results for extract yield (p<0.0001 and R2= 0.9941), TPC (p<0.0001 and R2= 0.9891), and DPPH radical scavenging activity (p<0.0001 and R2= 0.9692). Potent phenolic compounds were identified by GC-MS in GOF extract  and considerable amount of essential fatty acids were also detected. The current findings support the use of UAEE as an effective green route for optimized recovery of high-value components from GOF and hence its applications can be extended to functional food and nutra-pharmaceutical developments.

Development and Characterization of New Green Propolis Extract Formulations as Promising Candidates to Substitute for Green Propolis Hydroalcoholic Extract

The technologies used to produce the different dosage forms of propolis can selectively affect the original propolis compounds and their biological activities. The most common type of propolis extract is hydroethanolic. However, there is considerable demand for ethanol-free propolis presentations, including stable powder forms. Three propolis extract formulations were developed and investigated for chemical composition and antioxidant and antimicrobial activity: polar propolis fraction (PPF), soluble propolis dry extract (PSDE), and microencapsulated propolis extract (MPE). The different technologies used to produce the extracts affected their physical appearance, chemical profile, and biological activity. PPF was found to contain mainly caffeic and p-Coumaric acid, while PSDE and MPE showed a chemical fingerprint closer to the original green propolis hydroalcoholic extract used. MPE, a fine powder (40% propolis in gum Arabic), was readily dispersible in water, and had less intense flavor, taste, and color than PSDE. PSDE, a fine powder (80% propolis) in maltodextrin as a carrier, was perfectly water-soluble and could be used in liquid formulations; it is transparent and has a strong bitter taste. PPF, a purified solid with large amounts of caffeic and p-Coumaric acids, had the highest antioxidant and antimicrobial activity, and therefore merits further study. PSDE and MPE had antioxidant and antimicrobial properties and could be used in products tailored to specific needs.

Biochar-Dual Oxidant Composite Particles Alleviate the Oxidative Stress of Phenolic Acid on Tomato Seed Germination

Phenolic acid is a well-known allelochemical, but also a pollutant in soil and water impeding crop production. Biochar is a multifunctional material widely used to mitigate the phenolic acids allelopathic effect. However, phenolic acid absorbed by biochar can still be released. In order to improve the removal efficiency of phenolic acids by biochar, the biochar-dual oxidant (BDO) composite particles were synthesized in this study, and the underlying mechanism of the BDO particles in ameliorating p-coumaric acid (p-CA) oxidative damage to tomato seed germination was revealed. Upon p-CA treatment, the BDO composite particles application increased the radical length, radical surface area, and germination index by 95.0%, 52.8%, and 114.6%, respectively. Compared to using biochar or oxidants alone, the BDO particles addition resulted in a higher removal rate of p-CA and produced more O₂^•-, HO^•, SO₄^•- and ¹O₂ radicals via autocatalytic action, suggesting that BDO particles removed phenolic acid by both adsorption and free radical oxidation. The addition of BDO particles maintained the levels of the antioxidant enzyme activity close to the control, and reduced the malondialdehyde and H₂O₂ by 49.7% and 49.5%, compared to the p-CA treatment. Integrative metabolomic and transcriptomic analyses revealed that 14 key metabolites and 62 genes were involved in phenylalanine and linoleic acid metabolism, which increased dramatically under p-CA stress but down-regulated with the addition of BDO particles. This study proved that the use of BDO composite particles could alleviate the oxidative stress of phenolic acid on tomato seeds. The findings will provide unprecedented insights into the application and mechanism of such composite particles as continuous cropping soil conditioners.

Attenuation of hepatic fibrosis by p-Coumaric acid via modulation of NLRP3 inflammasome activation in C57BL/6 mice

A prolonged high-fat and high-sucrose (HFHS) diet induces hepatic inflammation and mediates hepatic stellate cell (HSC) activation, which result in hepatic fibrosis. Aberrant activation of the innate immune system components, such as the NOD-like receptor protein 3 (NLRP3) inflammasome, has been implicated in HSC activation and hepatic fibrosis. We have previously shown that p-coumaric acid (PCA)-enriched peanut sprout extracts exert anti-inflammatory effects. However, it is unknown whether PCA reduces hepatic fibrosis by modulating innate immunity and HSC activation. To test this hypothesis, C57BL/6 male mice were randomly assigned to three groups and fed low-fat (LF) diet (11% calories from fat), high-fat (HF) diet (60% calories from fat, 0.2% cholesterol) with sucrose drink (20% sucrose, HFHS), or HFHS diet with PCA treatment (HFHS+PCA, 50 mg/kg body weight, intraperitoneally) for 13 weeks. The results showed that PCA treatment (1) partly improved systemic insulin sensitivity without altering adiposity, (2) attenuated hepatic signaling pathways associated with NLRP3 inflammasome activation, including toll-like receptor 4 (TLR4)/nuclear factor kappa B (NFκB), and endoplasmic reticulum/oxidative stress, and (3) reduced circulating interleukin (IL)-1β levels. More importantly, PCA ameliorated hepatic fibrosis compared to that in the HFHS group, and the anti-fibrogenic effects of PCA were confirmed in vitro in transforming growth factor β (TGFβ) treated-LX-2 HSCs. The role of PCA in decreased NLRP3 activation and caspase-1 cleavage was recapitulated in primary bone marrow‒derived macrophages. These findings indicate that PCA contributes to the prevention of HFHS diet‒mediated liver fibrosis, partly by attenuating the activation of the NLRP3 inflammasome.

High-efficiency novel extraction process of target polyphenols using enzymes in hydroalcoholic media

Agro-industrial by-products are a sustainable source of natural additives that can replace the synthetic ones in the food industry. Grape pomace is an abundant by-product that contains about 70% of the grape's polyphenols. Polyphenols are natural antioxidants with multiple health-promoting properties. They are secondary plant metabolites with a wide range of solubilities. Here, a novel extraction process of these compounds was developed using enzymes that specifically liberates target polyphenols in the appropriate hydroalcoholic mixture. Tannase, cellulase, and pectinase retained 22, 60, and 52% of their activity, respectively, in ethanol 30% v/v. Therefore, extractions were tested in ethanol concentrations between 0 and 30% v/v. Some of these enzymes presented synergistic effects in the extraction of specific polyphenols. Maximum yield of gallic acid was obtained using tannase and pectinase enzymes in ethanol 10% v/v (49.56 ± 0.01 mg L^-1 h^-1); in the case of p-coumaric acid, by cellulase and pectinase treatment in ethanol 30% v/v (7.72 ± 0.26 mg L^-1 h^-1), and in the case of trans-resveratrol, by pectinase treatment in ethanol 30% v/v (0.98 ± 0.04 mg L^-1 h^-1). Also, the effect of enzymes and solvent polarity was analysed for the extraction of malvidin-3-O-glucoside, syringic acid, and quercetin. Previous studies were mainly focused on the maximization of total polyphenols extraction yields, being the polyphenolic profile the consequence but not the driving force of the optimization. In the present study, the basis of a platform for a precise extraction of the desire polyphenols is provided. KEY POINTS: • Enzymes can be used up to ethanol 30% v/v. • The specific enzymes' action determines the polyphenolic profile of the extracts. • The yields obtained of target polyphenols are competitive.

Biosensor-assisted titratable CRISPRi high-throughput (BATCH) screening for over-production phenotypes

With rapid advances in the development of metabolic pathways and synthetic biology toolkits, a persisting challenge in microbial bioproduction is how to optimally rewire metabolic fluxes and accelerate the concomitant high-throughput phenotype screening. Here we developed a biosensor-assisted titratable CRISPRi high-throughput (BATCH) screening approach that combines a titratable mismatch CRISPR interference and a biosensor mediated screening for high-production phenotypes in Escherichia coli. We first developed a programmable mismatch CRISPRi that could afford multiple levels of interference efficacy with a one-pot sgRNA pool (a total of 16 variants for each target gene) harboring two consecutive random mismatches in the seed region of sgRNA spacers. The mismatch CRISPRi was demonstrated to enable almost a full range of gene knockdown when targeting different positions on genes. As a proof-of-principle demonstration of the BATCH screening system, we designed doubly mismatched sgRNA pools targeting 20 relevant genes in E. coli and optimized a PadR-based p-coumaric acid biosensor with broad dynamic range for the eGFP fluorescence guided high-production screening. Using sgRNA variants for the combinatorial knockdown of pfkA and ptsI, the p-coumaric acid titer was increased by 40.6% to o 1308.6 mg/l from glycerol in shake flasks. To further demonstrate the general applicability of the BATCH screening system, we recruited a HpdR-based butyrate biosensor that facilitated the screening of E. coli strains achieving 19.0% and 25.2% increase of butyrate titer in shake flasks with sgRNA variants targeting sucA and ldhA, respectively. This work reported the establishment of a plug-and-play approach that enables multilevel modulation of metabolic fluxes and high-throughput screening of high-production phenotypes.

Establishing an Autonomous Cascaded Artificial Dynamic (AutoCAD) regulation system for improved pathway performance

Endogenous metabolic pathways in microbial cells are usually precisely controlled by sophisticated regulation networks. However, the lack of such regulations when introducing heterologous pathways in microbial hosts often causes unbalanced enzyme expression and carbon flux distribution, hindering the construction of highly efficient microbial biosynthesis systems. Here, using naringenin as the target compound, we developed an Autonomous Cascaded Artificial Dynamic (AutoCAD) regulation system to automatically coordinate the pathway expression and redirect carbon fluxes for enhanced naringenin production. The AutoCAD regulation system, consisting of both intermediate-based feedforward and product-based feedback control genetic circuits, resulted in a 16.5-fold increase in naringenin titer compared with the static control. Fed-batch fermentation using the strain with AutoCAD regulation further enhanced the naringenin titer to 277.2 mg/L. The AutoCAD regulation system, with intermediate-based feedforward control and product-triggered feedback control, provides a new paradigm of developing complicated cascade dynamic control to engineer heterologous pathways.

p-Coumaric acid protects against D-galactose induced neurotoxicity by attenuating neuroinflammation and apoptosis in mice brain

D-galactose (D-gal) induced senescence in rodents is a widely used model for assessment of molecules affecting brain ageing. Chronic administration of D-gal causes neuroinflammation leading to cognitive deficit and memory impairment which represent Alzheimer's dementia. In present study, we investigated the neuroprotective effects of the natural phenol, p-Coumaric acid (PCA) and its underlying mechanism in the chronic D-gal treated mice. Subcutaneous administration of D-gal (150 mg/kg) to Swiss albino mice for 42 consecutive days resulted in cognitive impairment as observed in Morris water maize (MWM) and Y maze test, which was ameliorated by concurrent treatment with PCA (80 mg/kg, and 100 mg/kg, p.o.). Importantly, PCA treatment attenuated the D-gal induced oxidative stress and significantly inhibited acetylcholinesterase (AChE) activity in mice brain. Furthermore, PCA treatment significantly lowered levels of inflammatory marker nuclear factor kappa B (NFκB) and reduced levels of proapoptotic enzyme caspase3. We also observed that PCA treatment exhibited β-secretase enzyme (BACE1) inhibitory effect. However, our results revealed that PCA treatment failed to decrease the level of advanced glycation end products both in vitro and in vivo. Taken together, current study demonstrated the significant neuroprotective effect of PCA against D-gal induced oxidative stress, neuroinflammation, cognitive impairment and apoptosis.

Functionalized cellulose nanocrystal embedded into citrus pectin coating improves its barrier, antioxidant properties and potential application in food

Due to the hydrophilic of the pectin material, the coating has poor barrier properties and a negative preservation effect on fresh fruits. In this study, citrus pectin coating with improved barrier and antioxidant properties was prepared by embedding with functional cellulose nanocrystals (CNC). It was assessed that cellulose nanocrystals grafted with p-coumaric acid (CNC-P) were uniformly dispersed in the pectin matrix to improve coating barrier properties. The addition of 8 % CNC-P to the pectin coating led to a decrease in water vapor and oxygen permeability from the coating by 12.6 % and 22.3 %, respectively. Additionally, the grafted p-coumaric acid (PA) introduced antioxidant properties to the cellulose nanocrystals. The fresh-cut fruits preservation assay showed that the coating containing CNC-P exerted a stronger inhibition effect of the browning process within 8 h than other coatings. This study suggests that pectin coating embedded with CNC-P has the potential to be used in food packaging.

LC-MS metabolomics of urine reveals distinct profiles for non-muscle-invasive and muscle-invasive bladder cancer

PURPOSE

Bladder cancer (BC) is among the most frequent malignancies worldwide. Novel non-invasive markers are needed to diagnose and stage BC with more accuracy than invasive procedures like cystoscopy. To date, no study has identified urine metabolites characteristic of all BC stages. To discover novel urine metabolomic profiles to diagnose and stage non-muscle-invasive (NMIBC) and muscle-invasive (MIBC) patients using mass spectrometry-based metabolomics.

METHODS

We prospectively recruited 198 BC patients and 98 age- and sex-matched healthy volunteers without evidence of renal or bladder condition confirmed by ultrasound, from whom we collected a first morning urine sample (before surgery in patients). In a discovery stage, an untargeted metabolomic analysis was conducted in urine samples of a selection of 64 BC patients (19 TaG1, 11 TaG3, 20 T1G3, 12 T2G3, 1 T2G2, 1 T3G3) and 20 controls to identify dysregulated metabolites. Next, after exhaustive multivariate analysis, confirmed dysregulated metabolites were validated in an independent cohort of 134 BC patients (19 TaG1, 62 TaG2, 9 TaG3, 15 T1G2, 16 T1G3, 4 T2G2, 9 T2G3) and 78 controls.

RESULTS

We validated p-cresol glucuronide as potential diagnostic biomarker for BC patients compared to controls (AUC = 0.79). For NMIBC, p-cresol glucuronide was valuable as staging biomarker (AUC = 0.803). And among NMIBCs, p-coumaric acid may be a potential specific staging biomarker for the TaG1 NMIBC; however, future validation experiments should be conducted once the precise version of the standard is commercially available. Remarkably, for MIBC we validated spermine as potential specific staging biomarker (AUC = 0.882).

CONCLUSION

Ours is the first metabolomics study conducted in urine of a thoroughly characterized cohort comprising all stages of NMIBC, MIBC and healthy controls in which we identified non-invasive diagnostic and staging biomarkers. These may improve BC management, thus reducing the use of current harmful diagnostic techniques.

Global transcriptomic response of Escherichia coli to p-coumaric acid

The aromatic compound p-coumaric acid (p-CA) is a secondary metabolite produced by plants. This aromatic acid and derived compounds have positive effects on human health, so there is interest in producing them in biotechnological processes with recombinant Escherichia coli strains. To determine the physiologic response of E. coli W3110 to p-CA, dynamic expression analysis of selected genes fused to a fluorescent protein reporter as well as RNA-seq and RT-qPCR were performed. The observed transcriptional profile revealed the induction of genes involved in functions related to p-CA active export, synthesis of cell wall and membrane components, synthesis of amino acids, detoxification of formaldehyde, phosphate limitation, acid stress, protein folding and degradation. Downregulation of genes encoding proteins involved in energy production, carbohydrate import and metabolism, as well as several outer and plasma membrane proteins was detected. This response is indicative of cell envelope damage causing the leakage of intracellular components including amino acids and phosphate-containing compounds. The cellular functions responding to p-CA that were identified in this study will help in defining targets for production strains improvement.

p-Coumaric acid attenuates high-fat diet-induced oxidative stress and nephropathy in diabetic rats

The prevalence of persistent hyperglycaemia during diabetes, impair antioxidant defence system and generate reactive oxygen species, which majorly contribute to its progression and associated complications. Phytochemicals were suggested to scavenge-free radicals and exert antioxidant effects required to improve insulin sensitivity and reduce the occurrence of diabetes-associated complications. We hypothesise that a phenolic phytochemical p-coumaric can reduce diabetes-induced oxidative stress and improve diabetes-associated nephropathy in rats. The aim of this study is to analyse the protective effects of p-coumaric acid against diabetes-induced oxidative stress and nephropathy in high-fat diet-induced diabetic rats. The oral feeding of p-coumaric acid (20 mg/kg for 12 weeks) was found to significantly decrease the elevated levels of blood glucose in high-fat diet-induced type 2 diabetic rats. p-Coumaric acid treatment also decreases the kidney weight whilst increasing the total body weight of diabetic rats. Furthermore whilst evaluation of the different renal functioning tests, p-coumaric acid significantly improves histopathological changes and the levels of urea, creatinine and uric acid in serum of diabetic rats, which was otherwise elevated under diabetic conditions. Our results also highlight that p-coumaric acid is an efficient compound with antioxidant properties and improves the diabetes-induced change in lipid peroxidation and activities of antioxidant enzymes: catalase, glutathione-S-transferase and superoxide dismutase. p-Coumaric acid thus possesses the potential to prevent diabetic nephropathy by reducing oxidative stress and can thus serve as a potential drug target for pharmaceutical companies.

Smart drug delivery of p-Coumaric acid loaded aptamer conjugated starch nanoparticles for effective triple-negative breast cancer therapy

The nano-drug delivery system utilizing the ligand functionalized nanoparticles have a tremendous application in cancer therapeutics. The present study was aimed to fabricate the p-Coumaric acid-loaded aptamer (ligand) conjugated starch nanoparticles (Apt-p-CA-AStNPs) for effective treatment of triple-negative breast cancer (MDA-MB-231). The FT-IR spectrum showed the presence of functional groups associated with para-Coumaric acid (p-CA) and amino starch (AS) in p-CA-AStNPs. Further, the conjugation of aptamer in p-CA-AStNPs was confirmed by agarose gel electrophoresis. Transmission electron microscopic analysis revealed that the synthesized Apt-p-CA-AStNPs were less agglomerated. The zeta size analyzer displayed the average particle size of 218.97 ± 3.07 nm with ȥ-potential -29.2 ± 1.35 mV, and PDI 0.299 ± 0.05 for Apt-p-CA-AStNPs. The drug encapsulation and loading efficiencies were 80.30 ± 0.53% and 10.35 ± 0.85% respectively for Apt-p-CA-AStNPs. Apt-p-CA-AStNPs showed a rapid and bursting release in the initial five hours of the experiment in pH 5.4. A significant change was found in their cytotoxic efficacy between the samples: p-CA, p-CA-AStNPs, and Apt-p-CA-AStNPs. Among the tested samples, Apt-p-CA-AStNPs caused higher cytotoxicity in MDA-MB-231 cells through ROS regulation, nuclear damage, mitochondrial membrane potential, and apoptosis-related protein expressions. Overall, these results proved that Apt-p-CA-AStNPs were efficiently inhibited the MDA-MB-231 cells by regulating apoptosis.

Cellular uptake of anthocyanins extracted from black soybean, grape, and purple sweet potato using INT-407 cells

This study combined in vitro digestion and INT-407 cells to evaluate the bioaccessibility of anthocyanins in the small intestinal epithelial cells. Black soybean, grape, and purple sweet potato were chosen as they have a different anthocyanin composition. After the aqueous extract was digested under in vitro gastric and intestinal conditions, the digested mixture was incubated in the media of INT-407 for 2 h at 37 °C. Low proportion (< 0.3%) of anthocyanins in black soybean and grape passed through cell membranes. Cyanidin-3-O-glucoside and pelargonidin-3-O-glucoside in black soybean and cyanidin-3-O-(6-O-p-coumaroyl)-5-O-diglucoside and delphinidin-3-O-(6-O-p-coumaroyl)-5-O-diglucoside in grape were found inside the cell. However, acylated anthocyanins containing three sugar moieties in purple sweet potato were not detected inside the cell. p-Coumaric acid was detected in the cells incubated with grape, but not in the media. These indicate that chemical structure of anthocyanins affected their cellular uptake and antioxidant activity in INT-407 cells.

Supplementary Information

The online version contains supplementary material available at 10.1007/s10068-021-00976-y.

Protective effects of p-coumaric acid against gentamicin-induced nephrotoxicity in rats

The most important side effect of gentamicin (GM) is nephrotoxicity. p-Coumaric acid (PCA) is a phenolic compound that scavenges free radicals, reduces fibrosis, and tissue damage. This study investigates the protective effect of PCA on tissue damage and kidney function in gentamicin-induced nephrotoxicity (GIN). Thirty-five rats were separated into five groups and each group contained seven animals: control group, ethanol group, GM group, PCA group, and GM + PCA group. At the end of the seven-day treatment, the rats were sacrificed after blood and kidney tissue samples were taken. While serum urea, creatinine, and neutrophil gelatinase-associated lipocalin (NGAL) levels increased significantly in the GM group compared to the control, they showed a significant decrease in the GM + PCA group compared to the GM. Serum tumor necrosis factor-α (TNF-α) and tissue malondialdehyde (MDA) levels were significantly increased in the GM group compared to the control. While the tissue total oxidant status (TOS) and oxidative stress index (OSI) values of the GM group were significantly higher than the control, they showed a significant decrease in the GM + PCA group compared to the GM. In the histopathological examination, significant tubular necrosis and tubulointerstitial inflammation were detected in the proximal tubules in the GM group compared to the control, while a significant decrease was observed in the severity of these findings in the GM + PCA group compared to the GM. This study shows that PCA has biochemical and histopathological ameliorating effects on GIN in the rat model.

Protective effects of p-coumaric acid against high-fat diet-induced metabolic dysregulation in mice

p-Coumaric acid (PC), a naturally occurring phytochemical, possesses antioxidant and anti-inflammatory properties; however, the mechanisms underlying its protective effects against obesity-related metabolic dysfunction are largely unknown. Here, we treated C57BL/6J mice to a high-fat diet (HFD) with or without PC (10 mg/kg body weight/day) for 16 weeks to determine whether PC ameliorates HFD-induced obesity, insulin resistance, inflammation, and non-alcoholic fatty liver disease (NAFLD). We found no significant differences in food intake and body weight between the groups. However, PC-treated mice showed significantly lower white adipose tissue (WAT) weight, adipocyte size, and plasma leptin level, which were associated with decreased lipogenic enzyme activity and mRNA expression of their genes in the epididymal WAT. Moreover, hepatic lipogenic enzymes activities and expression of their genes and proteins were decreased with concomitant increases in hepatic fatty acid oxidation and mRNA expression of its gene; fecal lipid excretion was significantly increased, resulting in decreased liver weight, hepatic lipid levels, lipid droplet accumulation, and plasma aspartate aminotransferase and lipid levels. Additionally, PC-treated mice showed lower fasting blood glucose, plasma resistin, and MCP-1 levels, HOMA-IR, and mRNA expression of inflammatory genes in the epididymal WAT and liver. Our findings reveal potential mechanisms underlying the action of PC against HFD-induced adiposity, NAFLD, and other metabolic disturbances.

p-Coumaric acid ameliorates ionizing radiation-induced intestinal injury through modulation of oxidative stress and pyroptosis

AIMS

Intestinal injury is a clinical problem related to radiotherapy or accidental exposure to ionizing radiation. This study aimed to investigate the protective effect of p-coumaric acid (CA) against radiation induced intestinal injury.

MAIN METHODS

The present study orally administered CA to C57BL/6 male mice at 30 min before total body irradiation and continued for 3 days post irradiation. Then, the mice were sacrificed at day 3.5 or 14 after irradiation, respectively. The blood was collected to analyze the inflammatory cytokines. The antioxidant indexes of jejunum tissues were determined. Hematoxylin and eosin staining and apoptosis analysis was studied to investigate the pathological changes of the jejunum tissues. In addition, quantitative real-time polymerase chain reaction (qRT-PCR) and western blot were carried out to determine the changes in mRNA and protein levels of jejunum tissues.

KEY FINDINGS

Compared with the only irradiated group, treatment with CA improved intestinal morphology and apoptosis, increased the villus height and the ratio of villus height to crypt depth. It also reduced the oxidative stress and inflammatory response. The molecular mechanism analysis showed that CA significantly inhibited the pyroptosis genes (Caspase-1, NLRP3 and AIM2) mRNA expression and improved the intestinal barrier genes expression.

SIGNIFICANCE

The results suggested that CA ameliorates ionizing radiation-induced intestinal injury by inhibition of oxidative stress, inflammatory response and pyroptosis.

Development of a growth coupled and multi-layered dynamic regulation network balancing malonyl-CoA node to enhance (2S)-naringenin biosynthesis in Escherichia coli

Metabolic heterogeneity and dynamic changes in metabolic fluxes are two inherent characteristics of microbial fermentation that limit the precise control of metabolisms, often leading to impaired cell growth and low productivity. Dynamic metabolic engineering addresses these challenges through the design of multi-layered and multi-genetic dynamic regulation network (DRN) that allow a single cell to autonomously adjust metabolic flux in response to its growth and metabolite accumulation conditions. Here, we developed a growth coupled NCOMB (Naringenin-Coumaric acid-Malonyl-CoA-Balanced) DRN with systematic optimization of (2S)-naringenin and p-coumaric acid-responsive regulation pathways for real-time control of intracellular supply of malonyl-CoA. In this scenario, the acyl carrier protein was used as a novel critical node for fine-tuning malonyl-CoA consumption instead of direct repression of fatty acid synthase commonly employed in previous studies. To do so, we first engineered a multi-layered DRN enabling single cells to concurrently regulate acpH, acpS, acpT, acs, and ACC in malonyl-CoA catabolic and anabolic pathways. Next, the NCOMB DRN was optimized to enhance the synergies between different dynamic regulation layers via a biosensor-based directed evolution strategy. Finally, a high producer obtained from NCOMB DRN approach yielded a 8.7-fold improvement in (2S)-naringenin production (523.7 ± 51.8 mg/L) with a concomitant 20% increase in cell growth compared to the base strain using static strain engineering approach, thus demonstrating the high efficiency of this system for improving pathway production.

Local administration of p-coumaric acid decreases lipopolysaccharide-induced acute lung injury in mice: In vitro and in silico studies

Acute lung injury (ALI) remains to cause a high rate of mortality in critically ill patients. It is known that inflammation is a key factor in the pathogenesis of lipopolysaccharide (LPS)-induced ALI, which makes it a relevant approach to the treatment of ALI. In this study, we evaluated the potential of nasally instilled p-coumaric acid to prevent LPS-induced ALI in mice, by evaluating its effects on cellular and molecular targets involved in inflammatory response via in vitro and in silico approaches. Our results demonstrated that p-coumaric acid reduced both neutrophil accumulation and pro-inflammatory cytokine abundance, and simultaneously increased IL-10 production at the site of inflammation, potentially contributing to protection against LPS-induced ALI in mice. In the in vitro experiments, we observed inhibitory effects of p-coumaric acid against IL-6 and IL-8 production in stimulated A549 cells, as well as reactive oxygen species generation by neutrophils. In addition, p-coumaric acid treatment decreased neutrophil adhesion on the TNF-α-stimulated endothelial cells. According to the in silico predictions, p-coumaric acid reached stable interactions with both the ATP-binding site of IKKβ as well as the regions within LFA-1, critical for interaction with ICAM-1, thereby suppressing the production of proinflammatory mediators and hindering the neutrophil infiltration, respectively. Collectively, these findings indicate that p-coumaric acid is a promising anti-inflammatory agent that can be used for developing a pharmaceutical drug for the treatment of ALI and other inflammatory disorders.

The blood and mRNA levels of antioxidant-related factors in common carp (Cyprinus carpio) fed p-Coumaric acid

The natural antioxidants are well known for their antioxidative activity without side effects when compared to antibiotics. Hence, the present study aimed at evaluating p-Coumaric acid as an antioxidant additive on the blood and mRNA levels of antioxidant-related factors in common carp (Cyprinus carpio). Fish fed the basal diet supplemented with p-Coumaric at 0, 0.5, 1, and 1.5 g/kg for 56 days, then the serum, intestine, and liver samples were collected. The growth performance of fish fed with CA showed significantly (P < 0.05) improved FW, WG, and SGR compared to those of the control one. However, the feed conversion ratio was significantly (P < 0.05) reduced in fish fed 1 and 1.5 g/kg diet levels. SOD was not significantly differed among the groups fed with varied p-Coumaric acid (P > 0.05). Serum GPX and TAC were enhanced considerably by p-Coumaric acid regarding the control with the highest being in fish fed 1.5 g/kg diet (P < 0.05). Serum CAT was more elevated in fish provided p-Coumaric acid at 1 or 1.5 g/kg than the control while fish fed 0.5 g/kg did not display significant changes. MDA level significantly decreased by all p-Coumaric acid groups compared to the control one, and the lowest level was observed in 1.5 g/kg (P < 0.05). The mRNA level of CAT was significantly upregulated in the liver by p-Coumaric acid at 1 or 1.5 g/kg (P < 0.05), while the intestine CAT did not influence by p-Coumaric acid (P > 0.05). The measured SOD in the liver and intestine samples revealed no changes in common carp fed p-Coumaric acid (P > 0.05). GPX was significantly upregulated in the intestine by p-Coumaric acid at 1 or 1.5 g/kg (P < 0.05), whereas the liver GPX was upregulated by p-Coumaric acid at 1.5 g/kg. The mRNA level of the GST gene in the intestine of common carp was upregulated by p-Coumaric acid at 1.5 g/kg, whereas the liver displayed upregulated GST in fish fed 1 g/kg diet. The present study approved the application of p-Coumaric acid as a natural antioxidant for friendly, sustainable aquaculture.

p-Coumaric Acid Enhances Hypothalamic Leptin Signaling and Glucose Homeostasis in Mice via Differential Effects on AMPK Activation

AMP-activated protein kinase (AMPK) plays a crucial role in the regulation of energy homeostasis in both peripheral metabolic organs and the central nervous system. Recent studies indicated that p-Coumaric acid (CA), a hydroxycinnamic phenolic acid, potentially activated the peripheral AMPK pathway to exert beneficial effects on glucose metabolism in vitro. However, CA’s actions on central AMPK activity and whole-body glucose homeostasis have not yet been investigated. Here, we reported that CA exhibited different effects on peripheral and central AMPK activation both in vitro and in vivo. Specifically, while CA treatment promoted hepatic AMPK activation, it showed an inhibitory effect on hypothalamic AMPK activity possibly by activating the S6 kinase. Furthermore, CA treatment enhanced hypothalamic leptin sensitivity, resulting in increased proopiomelanocortin (POMC) expression, decreased agouti-related peptide (AgRP) expression, and reduced daily food intake. Overall, CA treatment improved blood glucose control, glucose tolerance, and insulin sensitivity. Together, these results suggested that CA treatment enhanced hypothalamic leptin signaling and whole-body glucose homeostasis, possibly via its differential effects on AMPK activation.

An updated review of various medicinal applications of p-coumaric acid: From antioxidative and anti-inflammatory properties to effects on cell cycle and proliferation

P-Coumaric acid (p-CA) is a hydroxycinnamic acid, an organic compound that is a hydroxyl derivative of cinnamic acid. P-CA is the most abundant isomer of the three in nature and can be found in a wide variety of edible plants such as fungi, peanuts, navy beans, tomatoes, carrots, basil, and garlic. Recently, the therapeutic properties of p-CA have received a great deal of attention from the scientific society. Here, we described the medicinal effects of p-CA on various pathological conditions. This review was performed via evaluating PubMed reported studies from January 2010 to January 2020 also reference lists were checked to find additional studies. All intermediation or complementarity of animal models, case-control and cohort studies, in-vitro studies, and controlled trials (CTs) on p-CA were acceptable, although, plant extract studies without indication of main active substances were excluded due to the considerable diversities and heterogeneities. According to recent evidence regarding the beneficial effects of p-CA, numerous diseases such as nephropathies, cardiovascular diseases, neuro-inflammatory diseases, liver diseases, cancers, and some metabolic disorders could potentially control by this natural herb. Interestingly, autophagy is a novel molecular mechanism involved in the crosstalk between classic effects of p-CA and introduces alternative therapeutic pathways for this compound. Much work remains in clarifying the main therapeutic properties among the various p-CA effects; these will be the subject of forthcoming work, which could be resulting in presenting the further mechanism of action.

Development of p-Coumaric Acid Analysis in Human Plasma and Its Clinical Application to PK/PD Study

It has been recognized that p-Coumaric acid (p-CA) has protective effects as an antioxidant, anti-inflammatory agent. A sensitive and efficient Liquid Chromatography-Mass Spectrometry (LC-MS) method for maximum determination of p-CA in human plasma has been established using Ultra-performance liquid Chromatography-tandem mass Spectrometry (UPLC-MS/MS). This study provides the developed analysis of p-CA extracted from Bambusae Caulis in Taeniam (BC) to examine the improvement of the treatment p-CA, IGF-1 and Osteocalcin level in human children which are important factors on the growth of children’s height through Pharmacokinetics/Pharmacodynamics (PK/PD) model. p-CA and internal standard in a plasma sample were detected by the Multiple Reaction Monitoring (MRM) scan mode with positive ion detection. The sample participating in the study was made of 34 subjects (placebo = 18, treatment = 16). The subjects were enrolled to be randomized to the control group and BC group. Randomized subjects took tested treatment twice a day, three capsules with oral administration (258 mg/capsule) each time after a meal. Standard calibration curves (reproducibility) were constructed and the lower limit of quantitation (LLOQ) for p-CA was found to be 0.2 ng/mL on injection of the sample into the UPLC-MS/MS system. Accuracy and precision were evaluated and the intra-accuracy was 99.2–103.8% with precision of 1.0–5.6% and inter-accuracy was 99.6–108.4% and precision of 1.3–6.4% for p-CA. The method has been successfully applied to PK/PD studies of p-CA in human plasma. The p-CA, BC in Taeniam extract increased the level of IGF-1 and Osteocalcin, and changed the height from baseline, which suggested that the p-CA could play an important role in longitudinal bone growth. Therefore, the p-CA extracted from BC in Taeniam might be a good alternative medicine to growth hormone (GH) therapy.

Isolation, identification, and inhibitory enzyme activity of phenolic substances present in Spirulina

Spirulina species are edible with high nutritional as well as potential therapeutic values. In this work, we show that phenolic extracts from Spirulina (p-Coumaric acid) possessed inhibitory potential on α-glucosidase (IC₅₀  = 1.67 ± 0.02 mM) and tyrosinase (IC₅₀  = 52.71 ± 3.01 mM). Moreover, p-Coumaric acid inhibited α-glucosidase and tyrosinase in a reversible mixed-type manner. Interestingly, molecular docking demonstrated that p-Coumaric acid penetrated in depth of the active-site of tyrosinase and α-glucosidase by the noncovalent force or interaction. Among them, making polar interactions with Cu²⁺ ions and the amino acid residue capable of forming cation-π significantly contribute to the strong binding of p-Coumaric acid on tyrosinase. p-Coumaric acid was isolated and identified from Spirulina for the first time, which can be used as a lead compound for the design of functional food additives and skin-lightening active ingredient in cosmetics, and pharmaceuticals against type 2 diabetes. PRACTICAL APPLICATIONS: A natural, food-derived compound possessing the potential for the development of an anti-hyperglycaemic and skin-lightening supplement is very promising in cosmetics, functional food, and pharmaceuticals against type 2 diabetes. Herein, the present study is the first to present high levels of p-Coumaric acid from Spirulina, which simultaneously possessed inhibition potential on α-glucosidase and tyrosinase. Importantly, we gained initial information about the polypeptide-inhibitor interactions and underlying mechanisms for Spirulina's therapeutic effects, which will provide the bases for developing new drugs for preventing or treating type 2 diabetes and enzyme inhibitors. Moreover, this work also demonstrates the potential of the extraction of high-value chemicals from Spirulina waste.

Anti-fungal activity of phenolic sweet orange peel extract for controlling fungi responsible for post-harvest fruit decay

There is a growing interest in finding safe and natural anti-microbial compounds as a valid alternative to conventional chemical treatments for managing post-harvest fruit diseases. This study investigated the anti-fungal capacity of orange peel polyphenolic extract (OPE) against three relevant post-harvest fungal pathogens, Monilinia fructicola, Botrytis cinerea and Alternaria alternata. OPE extract at 1.5 g/L inhibited (100%) the mycelial growth and conidial germination of the three target fungi. At lower concentration, the effect varied, depending on the dose applied and target fungi. When the anti-fungal activity of the main phenolic compounds in sweet orange peel, namely, the flavonoids (naringin, hesperidin and neohesperidin) and phenolic acids (ferulic and p-coumaric), were evaluated, ferulic acid and p-coumaric acid displayed significantly higher inhibitory capacity in synthetic medium, while the activity of flavonoids was limited. Synergism between compounds was not detected, and the inhibitory activity of OPE may be attributed to an additive effect of phenolic acids. Interestingly, in peach-based medium, ferulic acid remained active against M. fructicola and A. alternata and was more efficient than p-coumaric to control B. cinerea. These results highlight peel orange waste as an excellent source of anti-fungal compounds, suggesting the possibility of using ferulic acid or ferulic acid-rich extracts, either alone or in combination with other post-harvest treatment, as a natural alternative to reduce post-harvest losses and, also, enhance the shelf-life of fruit.

Alkaline organosolv pretreatment of different sorghum stem parts for enhancing the total reducing sugar yields and p-coumaric acid release

BACKGROUND

The sorghum stem can be divided into the pith and rind parts with obvious differences in cell type and chemical composition, thus arising the different recalcitrance to enzyme hydrolysis and demand for different pretreatment conditions. The introduction of organic solvents in the pretreatment can reduce over-degradation of cellulose and hemicellulose, but significance of organic solvent addition in pretreatment of different parts of sorghum stem is still unclear. Valorization of each component is critical for economy of sorghum biorefinery. Therefore, in this study, NaOH-ethanol pretreatment condition for different parts of the sorghum stem was optimized to maximize p-coumaric acid release and total reducing sugar recovery.

RESULT

Ethanol addition improved p-coumaric acid release and delignification efficiency, but significantly reduced hemicellulose deconstruction in NaOH-ethanol pretreatment. Optimization using the response surface methodology revealed that the pith, rind and whole stem require different NaOH-ethanol pretreatment conditions for maximal p-coumaric acid release and xylan preservation. By respective optimal NaOH-ethanol pretreatment, the p-coumaric acid release yields reached 94.07%, 97.24% and 95.05% from pith, rind and whole stem, which increased by 8.16%, 8.38% and 8.39% compared to those of NaOH-pretreated samples. The xylan recoveries of pith, rind and whole stem reached 76.80%, 88.46% and 85.01%, respectively, which increased by 47.75%, 15.11% and 35.97% compared to NaOH pretreatment. Adding xylanase significantly enhanced the enzymatic saccharification of pretreated residues. The total reducing sugar yields after respective optimal NaOH-ethanol pretreatment and enzymatic hydrolysis reached 84.06%, 82.29% and 84.09% for pith, rind and whole stem, respectively, which increased by 29.56%, 23.67% and 25.56% compared to those of NaOH-pretreated samples. Considering the separation cost of the different stem parts, whole sorghum stem can be directly used as feedstock in industrial biorefinery.

CONCLUSION

These results indicated that NaOH-ethanol is effective for the efficient fractionation and pretreatment of sorghum biomass. This work will help to understand the differences of different parts of sorghum stem under NaOH-ethanol pretreatment, thereby improving the full-component utilization of sorghum stem.

Optimization of the l-tyrosine metabolic pathway in Saccharomyces cerevisiae by analyzing p-coumaric acid production

In this study, we applied a series of genetic modifications to wild-type S. cerevisiae strain BY4741 to address the bottlenecks in the l-tyrosine pathway. A tyrosine ammonia-lyase (TAL) gene from Rhodobacter capsulatus, which can catalyze conversion of l-tyrosine into p-coumaric acid, was overexpressed to facilitate the analysis of l-tyrosine and test the strain's capability to synthesize heterologous derivatives. First, we enhanced the supply of precursors by overexpressing transaldolase gene TAL1, enolase II gene ENO2, and pentafunctional enzyme gene ARO1 resulting in a 1.55-fold increase in p-coumaric acid production. Second, feedback inhibition of 3-deoxy-d-arabino-heptulosonate-7-phosphate synthase and chorismate mutase was relieved by overexpressing the mutated feedback-resistant ARO4 ^K229L and ARO7 ^G141S , and a 3.61-fold improvement of p-coumaric acid production was obtained. Finally, formation of byproducts was decreased by deleting pyruvate decarboxylase gene PDC5 and phenylpyruvate decarboxylase gene ARO10, and p-coumaric acid production was increased 2.52-fold. The best producer-when TAL1, ENO2, ARO1, ARO4 ^K229L , ARO7 ^G141S , and TAL were overexpressed, and PDC5 and ARO10 were deleted-increased p-coumaric acid production by 14.08-fold (from 1.4 to 19.71 mg L^-1). Our study provided a valuable insight into the optimization of l-tyrosine metabolic pathway.

Effects of p-coumaric acid on microRNA expression profiles in SNU-16 human gastric cancer cells

BACKGROUND

p-Coumaric acid (p-CA), a phenolic compound abundantly found in edible plants, was found to induce apoptosis in SNU-16 gastric cancer cells. However, the effects of p-CA on the microRNA expression pattern in SNU-16 cells have not been reported.

OBJECTIVES

The primary objective of this study was to investigate microRNA expression profiles in p-CA-treated SNU-16 cells.

METHODS

SNU-16 cells were treated with 1.5 mM p-CA for 48 h. High-throughput RNA sequencing was performed. The accuracy and validity of the RNA sequencing results were tested by real-time PCR. Gene Ontology (GO) enrichment and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses were performed using the differentially expressed microRNAs (DEMs).

RESULTS

Thirty-two DEMs were identified between p-CA-treated and control cells, 9 of which were upregulated, and 23 downregulated. GO and KEGG pathway analyses of the target genes indicated that these genes were involved in a variety of biological functions and several cancer-related pathways. The miRNA interactive network analysis identified hsa-miR-125a-5p, hsa-miR-30a-5p, and hsa-miR-7-5p as the major nodes.

CONCLUSIONS

Our findings indicated that p-CA exerted its anticancer effects in SNU-16 gastric cancer cells by modulating the expression of certain microRNAs, providing a better understanding of the anticancer properties of p-CA in gastric cancer cells.

Antioxidant effect of p-coumaric acid on interleukin 1-β and tumor necrosis factor-α in rats with renal ischemic reperfusion

BACKGROUND AND AIMS

Renal ischemia-reperfusion occurs in some clinical conditions such as kidney surgery that can leads to acute renal failure. The aim of this study was to investigate the effect of p-coumaric acid (CA) on ischemia reperfusion (I/R) injury.

METHODS

Thirty rats were randomly divided into five groups; control, CA (100mg/kg), I/R, propylene glycol (10%)+I/R and CA+I/R, (n=6 each). CA and propylene glycol were administered orally for 2 weeks. Then, the rats were subjected to bilateral renal ischemia for 45min and followed by reperfusion for 24h. All rats were killed and kidney function tests, tissue malondialdehyde and activity of antioxidant enzymes were determined. Histopathological evaluations were also performed. In addition, renal expression of the tumor necrosis factor-α and interleukin-1β were determined using enzyme-linked immunosorbent assay and immunohistochemistry.

RESULTS

CA significantly improved the Cr and BUN levels in CA+I/R group compared to I/R group (p<0.005 and p<0.001, respectively). Reduction of tissue superoxide dismutase, glutathione peroxidase and catalase, were significantly improved by CA (p<0.01, p<0.01 and p<0.05). Treatment with CA also resulted in significant reduction in tissue MDA (p<0.05), TNF-α (p<0.001) and interleukin-1β expression (p<0.001) that were increased by renal I/R. Also, the rats treated with CA had nearly normal structure of the kidney.

CONCLUSIONS

The present findings suggest that, CA protects the kidneys against I/R injury via its antioxidant and anti-inflammatory effects.

Characterization of two new aromatic amino acid lyases from actinomycetes for highly efficient production of p-coumaric acid

p-Coumaric acid (p-CA) is a bioactive natural product and an important industrial material for pharmaceuticals and nutraceuticals. It can be synthesized from deamination of L-tyrosine by tyrosine ammonia lyase (TAL). In this work, we discovered two aromatic amino acid lyase genes, Sas-tal and Sts-tal, from Saccharothrix sp. NRRL B-16348 and Streptomyces sp. NRRL F-4489, respectively, and expressed them in Escherichia coli BL21(DE3). The two enzymes were functionally characterized as TAL. The optimum reaction temperature for Sas-TAL and Sts-TAL is 55 °C and 50 °C, respectively; while, the optimum pH for both TALs is 11. Sas-TAL had a k_cat/K_m value of 6.2 μM^-1 min^-1, while Sts-TAL had a much higher efficiency with a k_cat/K_m value of 78.3 μM^-1 min^-1. Both Sts-TAL and Sas-TAL can also take L-phenylalanine as the substrate to yield trans-cinnamic acid, and Sas-TAL showed much higher phenylalanine ammonia lyase activity than Sts-TAL. Using E. coli/Sts-TAL as a whole-cell biocatalyst, the productivity of p-CA reached 2.88 ± 0.12 g (L h)^-1, which represents the highest efficiency for microbial production of p-CA. Therefore, this work not only reports the identification of two new TALs from actinomycetes, but also provides an efficient way to produce the industrially valuable material p-CA.

p-Coumaric acid attenuates alcohol exposed hepatic injury through MAPKs, apoptosis and Nrf2 signaling in experimental models

Overconsumption of alcohol could lead to severe liver injury that connects with oxidative stress, apoptosis, and inflammatory response. Previously, we proved that p-coumaric acid prevents ethanol induced reproductive toxicity; however, p-coumaric acid (PCA) on ethanol mediated hepatotoxicity has not been examined yet. In our work, we sought to study the potential of PCA in contradiction of ethanol induced hepatoxicity which linking with MAPKs, apoptosis, oxidative stress, and Nrf2 signaling. Foremost, we found that PCA could protect ethanol induced both L-02 and HepG2 hepatic cells by inhibiting cytotoxicity, ROS production, mitochondrial depolarization, and nuclear fragmentation. Also, in vivo experiments showed that the ethanol increasing the lipid markers (TBARS, CD) and depletes the antioxidants thereby increased phosphorylation of JNK, ERK, and p38 in rat liver tissues. Interestingly, PCA treatments inhibit ethanol exposed lipid markers and depletion of antioxidants, which directs the inhibition of MAPKs activation in rat liver tissues. We also noticed that the PCA protected ethanol induced apoptosis and liver markers by inhibiting the expression of Bax, caspases; AST, ALT, ALS, and LDH in liver tissue. Overall, the ameliorative consequence of PCA on ethanol induced oxidative stress and apoptosis was achieved by suppressing the expression of CYP2E1 and overexpressing Nrf2 and its target protein HO-1 in rat liver tissue. As a result, PCA was marked to be an effective antioxidant with notable hepatoprotection by inhibiting MAPKs and apoptosis signaling via enhancing Nrf2 signaling.

P-Coumaric Acid Mitigates Doxorubicin-Induced Nephrotoxicity Through Suppression of Oxidative Stress, Inflammation and Apoptosis

BACKGROUND AND AIMS

P-Coumaric acid (PCA) is one the compound that has free radical scavenging effects. This study investigates the protective effect of PCA on tissue damage in DOX-induced nephrotoxicity.

METHODS

Thirty two Wistar rats were divided into control, PCA, DOX (15 mg/kg, i.p.) and DOX plus PCA (100 mg/kg, orally) groups. DOX-induced nephrotoxicity was indicated by marked increase in blood urea nitrogen (BUN) and serum creatinine (Cr) compared to controls. DOX group also showed elevations in lipid peroxidation and reductions in enzyme activities of superoxide dismutase (SOD), glutathione peroxidase (GPx) and catalase (CAT). Expression of renal inflammatory cytokines including tumor necrosis factor alpha (TNF-α) and interleukin-1 beta (IL-1β) and apoptosis were also elevated in the DOX group.

RESULTS

PCA significantly reversed, nephrotoxicity induced by DOX via lowering BUN, serum Cr and improving histopathological scores as compared to the DOX group. PCA also decreased lipid peroxidation, increased activities of GPx, SOD and CAT, to levels relatively comparable to control. Significant reductions in expression of TNF-α, IL-1β and apoptosis were also observed following Co-administration of PCA relative to the DOX group.

CONCLUSIONS

Results describe a protective effect of PCA against DOX-induced nephrotoxicity. This effect is likely facilitated through inhibition of oxidative stress, inflammation and apoptosis.

Antioxidant effect of p-coumaric acid on interleukin 1-β and tumor necrosis factor-α in rats with renal ischemic reperfusion

BACKGROUND AND AIMS

Renal ischemia-reperfusion occurs in some clinical conditions such as kidney surgery that can leads to acute renal failure. The aim of this study was to investigate the effect of p-coumaric acid (CA) on ischemia reperfusion (I/R) injury.

METHODS

Thirty rats were randomly divided into five groups; control, CA (100mg/kg), I/R, propylene glycol (10%)+I/R and CA+I/R, (n=6 each). CA and propylene glycol were administered orally for 2 weeks. Then, the rats were subjected to bilateral renal ischemia for 45min and followed by reperfusion for 24h. All rats were killed and kidney function tests, tissue malondialdehyde and activity of antioxidant enzymes were determined. Histopathological evaluations were also performed. In addition, renal expression of the tumor necrosis factor-α and interleukin-1β were determined using enzyme-linked immunosorbent assay and immunohistochemistry.

RESULTS

CA significantly improved the Cr and BUN levels in CA+I/R group compared to I/R group (p<0.005 and p<0.001, respectively). Reduction of tissue superoxide dismutase, glutathione peroxidase and catalase, were significantly improved by CA (p<0.01, p<0.01 and p<0.05). Treatment with CA also resulted in significant reduction in tissue MDA (p<0.05), TNF-α (p<0.001) and interleukin-1β expression (p<0.001) that were increased by renal I/R. Also, the rats treated with CA had nearly normal structure of the kidney.

CONCLUSIONS

The present findings suggest that, CA protects the kidneys against I/R injury via its antioxidant and anti-inflammatory effects.

Comparative transcriptome analysis of genomic region deletion strain with enhanced L-tyrosine production in Saccharomyces cerevisiae

OBJECTIVE

To determine the effect of large genomic region deletion in a Saccharomyces cerevisiae strain on tyrosine yield and to identify new genetic modification targets through transcriptome analysis.

RESULTS

TAL was used to produce p-coumaric acid (p-CA) from tyrosine to quantity tyrosine yield. S. cerevisiae mutant strain NK14 with deletion of a 23.8 kb genomic region was identified to have p-CA production of 10.3 mg L^- 1, while the wild-type strain BY4741 had p-CA production of 1.06 mg L^- 1. Analysis of growth patterns and stress tolerance showed that the deletion did not affect the growth phenotype of NK14. Transcriptome analysis suggested that, compared to BY4741, genes related to glycolysis (ENO2, TKL1) and the tyrosine pathway (ARO1, ARO2, ARO4, ARO7, TYR1) were upregulated in NK14 at different levels. Besides genes related to the tyrosine biosynthetic pathway, amino acid transporters (AVT6, VBA5, THI72) and transcription factor (ARO80) also showed changes in transcription levels.

CONCLUSIONS

We developed a strain with improved tyrosine yield and identified new genetic modification candidates for tyrosine production.

Metabolic engineering and transcriptomic analysis of Saccharomyces cerevisiae producing p-coumaric acid from xylose

BACKGROUND

Aromatic amino acids and their derivatives are valuable chemicals and are precursors for different industrially compounds. p-Coumaric acid is the main building block for complex secondary metabolites in commercial demand, such as flavonoids and polyphenols. Industrial scale production of this compound from yeast however remains challenging.

RESULTS

Using metabolic engineering and a systems biology approach, we developed a Saccharomyces cerevisiae platform strain able to produce 242 mg/L of p-coumaric acid from xylose. The same strain produced only 5.35 mg/L when cultivated with glucose as carbon source. To characterise this platform strain further, transcriptomic analysis was performed, comparing this strain's growth on xylose and glucose, revealing a strong up-regulation of the glyoxylate pathway alongside increased cell wall biosynthesis and unexpectedly a decrease in aromatic amino acid gene expression when xylose was used as carbon source.

CONCLUSIONS

The resulting S. cerevisiae strain represents a promising platform host for future production of p-coumaric using xylose as a carbon source.

Urinary excretion rate and bioavailability of chlorogenic acid, caffeic acid, p-coumaric acid, and ferulic acid in non-fasted rats maintained under physiological conditions

Hydroxycinnamic acids (HAs) are one of the major classes of phenolic compounds and epidemiological studies have suggested that they have beneficial health effects. This study aimed to determine the urinary excretion rate of chlorogenic acid, caffeic acid, p-coumaric acid, and ferulic acid in non-fasted rats and to estimate their bioavailability under physiological conditions. Previous studies have primarily used fasted animals, which exhibit severe changes in various physiological processes. Furthermore, the food matrix can affect HA bioavailability. Thus, our studies using non-fasted rats under physiological conditions may allow for a more accurate determination of both the HA urinary excretion rate and the bioavailability of HAs. HAs were successively gavaged to rats at a dose of 40 mg/kg body weight (BW) with a wash-out period of one week. The rats were fed the AIN-93M diet throughout the experiment. The urine was collected at time intervals of 0–6 h, 6–24 h, and 24–48 h after HA administration. Ingested HAs, except chlorogenic acid, were primarily excreted in the urine within 0–6 h as free forms or conjugated (glucuronidated and/or sulfated) forms. The majority of the ingested chlorogenic acid was detected in the urine at 6–24 h or 24–48 h as caffeic acid, p-coumaric acid, ferulic acid, and their conjugates. The total urinary excretion rate (% of the dose) at 48 h was ferulic acid (73.2%) > caffeic acid (61.6%) > p-coumaric acid (54.1%) >> chlorogenic acid (4.9%). The percentages of the conjugates in the urine differed amongst the rats gavaged with the individual HAs (74% for chlorogenic acid, 83% for caffeic acid, 68% for p-coumaric acid, and 96% for ferulic acid), which may be explained by their distinct bioactivities. These data reveal that caffeic acid, p-coumaric acid, and ferulic acid are much more bioavailable than chlorogenic acid, even though they are excreted more rapidly than chlorogenic acid. Our findings may provide additional insight into the health benefits of HAs and how they function in the body.

Effect of light, oxygen and temperature on the stability of artepillin C and p-coumaric acid from Brazilian green propolis

Brazilian Green Propolis (BGP) is an important bee product, which displays important biological activities, making it valuable in the international market. The major prenylated phenolic compound in BPG is (E)-artepillin C, along with its precursor (E)-p-coumaric acid, both contributing to the biological effects of BGP. Taking that into account, it was evaluated the effect of light, temperature and air oxygen in their content to establish the best storage and transport conditions for crude BGP and the pure compounds. For that, (E)-artepillin C and (E)-p-coumaric acid were initially submitted to degradation for five days under sunlight and high temperature (50 °C), furnishing three major (E)-Artepillin C isomers and one from (E)-p-coumaric acid. Then, it was developed and validated a Reverse Phase High Performance Liquid Chromatography (RP-HPLC) method for quantifying these compounds in crude BGP and in its extracts. In the stability studies, it was used a Full Factorial and Central Composite Design to establish the desirable storage conditions. (E)-Artepillin C, both pure and in BGP should be kept protected from light and storage below -2.5 °C. (E)-p-Coumaric acid can be stored at room temperature. Therefore, the best storage and transport conditions to keep the content of both compounds in BGP are protection from light at low temperatures.

p-Coumaric acid inhibits the Listeria monocytogenes RecA protein functions and SOS response: An antimicrobial target

Bacterial RecA plays an important role in the evaluation of antibiotic resistance via stress-induced DNA repair mechanism; SOS response. Accordingly, RecA became an important therapeutic target against antimicrobial resistance. Small molecule inhibitors of RecA may prevent adaptation of antibiotic resistance mutations and the emergence of antimicrobial resistance. In our study, we observed that phenolic compound p-Coumaric acid as potent RecA inhibitor. It inhibited RecA driven biochemical activities in vitro such as ssDNA binding, strand exchange, ATP hydrolysis and RecA coprotease activity of E. coli and L. monocytogenes RecA proteins. The mechanism underlying such inhibitory action of p-Coumaric acid involves its ability to interfere with the DNA binding domain of RecA protein. p-Coumaric acid also potentiates the activity of ciprofloxacin by inhibiting drastic cell survival of L. monocytogenes as well as filamentation process; the bacteria defensive mechanism in response to DNA damage. Additionally, it also blocked the ciprofloxacin induced RecA expression leading to suppression of SOS response in L. monocytogenes. These findings revealed that p-Coumaric acid is a potent RecA inhibitor, and can be used as an adjuvant to the existing antibiotics which not only enhance the shelf-life but also slow down the emergence of antibiotic resistance in bacteria.

Bio-guided fractionation to identify Senegalia gaumeri leaf extract compounds with anthelmintic activity against Haemonchus contortus eggs and larvae

Small ruminants browsing in tropical forests readily consume the foliage of Senegalia gaumeri. A S. gaumeri methanol:water extract was recently shown to have ovicidal activity against Haemonchus contortus eggs in vitro. In the present study, the fraction of a S. gaumeri methanol:water extract with ovicidal activity against H. contortus eggs and the metabolites potentially involved in this activity were identified. Bio-guided fractionation of the S. gaumeri methanol:water extract identified high ovicidal activity (80.29%, EC₅₀ = 58.9 μg/mL) in the non-polar sub-fraction P1. Gas chromatography-mass spectrometry (GC-MS) identified several fatty acids: pentacosane (18.05%), heneicosane (18.05%), triacontane (30.94%), octacosane (18.05%), and hexanedioic acid bis-(2-ethylhexyl) ester (32.72%). Purification of the polar components of sub-fraction P1 led to the identification of p-coumaric acid as a major constituent. In egg hatch tests, 400 μg/mL p-coumaric acid resulted in an ovicidal effect of 8.7%, a larvae failing eclosion effect of 2.9%, and of the emerged larvae (88.4%), many were damaged. In conclusion, the low AH activity of p-coumaric acid against H. contortus eggs indicates that it is not solely responsible for the ovicidal activity of sub-fraction P1 but might act in synergy with other compounds in this fraction. However, p-coumaric acid showed potential anthelmintic effects against the larval stage of H. contortus.

Construction of synthetic pathways for raspberry ketone production in engineered Escherichia coli

Raspberry ketone is an important ingredient in the flavor and fragrance industries. Due to its low content in fruits and vegetables, the production of natural raspberry ketone using heterologous synthesis in microbial strains is recently attracting increased attention. In this work, a heterologous pathway to produce raspberry ketone from p-coumaric acid, including 4-coumarate: CoA ligase (4CL), benzalacetone synthase (BAS), and raspberry ketone/zingerone synthase (RZS1) from plants, was successfully assembled in Escherichia coli. When the RZS1 gene was introduced into E. coli and co-expressed with two other genes, the intermediate 4-hydroxybenzylidene acetone in the pathway was almost completely transformed into a raspberry ketone. Substituting TB medium for M9 medium increased raspberry ketone titers by 3-4 times. Furthermore, the heterologous pathway was partitioned into two modules; module one produced p-coumaroyl-CoA from p-coumaric acid by 4CL, and module two produced raspberry ketone from coumaroyl-CoA by the action of BAS and RZS1. Optimizing the balanced expression of the two modules, it was shown that moderate expression of module one and high expression of module two was the best combination to enhance raspberry ketone production. The engineered strain CZ-8 reached 90.97 mg/l of raspberry ketone, which was 12 times higher than previously reported. In addition, the preferred approach of the heterologous pathway was related to the heterologous genes from different sources; for example, 4CL from Arabidopsis thaliana seemed to be more suitable for raspberry ketone production than that from Petroselinum crispum. This work paves an alternative way for future economic production of natural raspberry ketone.