Anti-osteoporotic effects of syringic acid and vanilic acid in the extracts of waste beds after mushroom cultivation

Research hotspots and emerging trends in growth and development of macrofungi: a bibliometric review based on CiteSpace analysis

Macrofungi (or mushrooms) are essential for agriculture, food, and ecology. Although research on the growth and development of macrofungi (GDM) can provide insights into their biological characteristics and metabolite synthesis mechanisms, further exploration is needed for a systematic and visual analysis of the current research progress on GDM. To comprehensively understand the research status and development trend of GDM, a total of 545 scientific literature related to GDM in the Web of Science Core Collection database from 2008 to 2024 were searched and selected as research objects. The general information (publication year, country, institution, and cited journal) and the specific information (co-authorship, keyword co-occurrence, and references with strong citation bursts) were mined and visualized in detail based on CiteSpace software. These analyses demonstrated that related research is still fashionable, and China is dominant and influential in this field. More frequent and in-depth cooperation among authors, institutions and regions is conducive to promoting the research on GDM. Additionally, the quantity and cluster analyses of keywords and references demonstrated that medicinal/edible macrofungi and sustainable development (e.g. mushroom substrate reuse) may be research hotspots and will remain popular in the coming years. This research aims to supply researchers with up-to-date knowledge and cutting-edge issues related to GDM by providing a visually appealing representations on quantitative GDM studies.

Status and development of spent mushroom substrate recycling: A review

The edible mushroom industry is the sixth largest after grain, cotton, oil, vegetables and fruits, and the annual production of edible mushrooms in China exceeds 40 million tons. Edible mushroom cultivation produces a class of by-products consisting mainly of mycelium remnants and lignocellulosic waste, known as Spent Mushroom Substrate (SMS) or Spent Mushroom Compost (SMC). SMS/SMC is rich in nutrients and active ingredients and has an extremely high recycling potential. This review paper summarizes SMS recycling strategies from the perspectives of "environmental remediation" and "circular economy", and briefly discusses the legitimacy, possible challenges and future research of SMS recycling. It is hoped that this will assist researchers in related fields and promote the development of the SMS recycling industry, thereby contributing to sustainable environmental and economic development.Implications: The efficient management of SMS is important for many countries around the world, particularly major mushroom producing countries. Traditional disposal methods (incineration, burial, piling) can cause serious damage to the environment and waste resources. The correct disposal method can protect the natural environment and provide certain economic benefits. This study presents the main methods of SMS processing from both an "environmental remediation" and "circular economy" perspective. In general, this paper emphasizes the importance of SMS processing, introduces the current mainstream processing methods and briefly discusses the legality of their processing methods.

Emerging technologies for the extraction of bioactives from mushroom waste

Extraction of bioactive compounds for application in nutraceuticals is gaining popularity. For this, there is a search for low-cost substrates that would make the end product and the process more economical. Mushroom waste (stalk, cap, stem etc.) is one such high valued substrate that has received much attention recently due to its rich reserves of terpenoids, polyphenols, sesquiterpenes, alkaloids, lactones, sterols, antioxidative vitamins, anthocyanidins, glycoproteins and polysaccharides, among others. However, there is a need to identify green and hybrid technologies that could make the bioactive extraction process from these substrates safe, efficient and sustainable. To this effect, many emerging technologies (supercritical fluid, ultrasound-, enzyme- and microwave-assisted extraction) have been explored in the last decade which have shown potential for scale-up with high productivity. This review systematically discusses such technologies highlighting the current challenges faced during waste processing and the research directives needed for further advancements in the field.

Protective effect of Pterospermum rubiginosum bark extract on bone mineral density and bone remodelling in estrogen deficient ovariectomized Sprague-Dawley (SD) rats

Osteoporosis is a common metabolic old age disorder characterised by low bone mass content (BMC) and mineral density (BMD) with micro-architectural deterioration of the extracellular matrix, further increasing bone fragility risk. Several traditional remedies, including plant extracts and herbal formulations, are used worldwide by local healers to improve the overall bone health and metabolism as an excellent osteoregenerative agent. Pteropsermum rubiginosum is an underexplored medicinal plant used by tribal peoples of Western Ghats, India, to treat bone fractures and associated inflammation. The proposed study evaluates the elemental profiling and phytochemical characterisation of P. rubiginosum methanolic bark extract (PRME), along with detailed In vitro and In vivo biological investigation in MG-63 cells and Sprague-Dawley (SD) rats. AAS and ICP-MS analysis showed the presence of calcium, phosphorus, and magnesium and exceptional levels of strontium, chromium, and zinc in PRME. The NMR characterisation revealed the presence of vanillic acid, Ergost-4-ene-3-one and catechin. The molecular docking studies revealed the target pockets of isolated compounds and various marker proteins in the bone remodelling cycle. In vitro studies showed a significant hike in ALP and calcium content, along with upregulated mRNA expression of the ALP and COL1, which confirmed the osteoinductive activity of PRME in human osteoblast-like MG-63 cells. The in vivo evaluation in ovariectomised (OVX) rats showed remarkable recovery in ALP, collagen and osteocalcin protein after 3 months of PRME treatment. DEXA scanning reports in OVX rats supported the above in vitro and in vivo results, significantly enhancing the BMD and BMC. The results suggest that PRME can induce osteogenic activity and enhance bone formation with an excellent osteoprotective effect against bone loss in OVX animals due to estrogen deficiency.

Supplementary Information

The online version contains supplementary material available at 10.1007/s13205-024-03942-7.

Lentinula Edodes Mycelia extract regulates the function of antigen-presenting cells to activate immune cells and prevent tumor-induced deterioration of immune function

Immune cell activation is essential for cancer rejection; however, the tumor microenvironment leads to deterioration of immune function, which enables cancer cells to survive and proliferate. We previously reported that oral ingestion of Lentinula Edodes Mycelia (L.E.M.) extract enhances the tumor antigen-specific T-cell response and exerts an antitumor effect in a tumor-bearing mouse model. In this study, we focused on antigen-presenting cells (APCs) located upstream of the immune system, induced a T-cell response, then examined the impact of L.E.M. extract on the APCs. L.E.M. extract enhanced the expression of MHC-I, MHC-II, CD86, CD80, and CD40 in bone marrow-derived dendritic cells (DCs) and strongly induced the production of IL-12. L.E.M.-stimulated DCs enhanced IFN-γ production from CD8+ T cells and induced their differentiation into effector cells. Furthermore, L.E.M. extract promoted IL-12 production and suppressed the production of IL-10 and TGF-β by transforming bone marrow-derived macrophages into M1-like macrophages. Furthermore, in a B16F10 melanoma inoculation model, DCs in the spleen were decreased and their activation was suppressed by the presence of cancer; however, ingestion of L.E.M. extract prevented this functional deterioration of DCs. In the spleen of cancer-bearing mice, the number of CD11b- F4/80+ macrophages in a hypoactivated state was also increased, whereas L.E.M. extract suppressed the increase of such macrophages. These findings suggest that L.E.M. extract may exhibit an antitumor immune response by regulating the function of APCs to induce cytotoxic T lymphocytes, as well as by suppressing the decline in antigen-presenting cell activity caused by the presence of cancer.

Metabolic engineering of plant secondary metabolites: prospects and its technological challenges

Plants produce a wide range of secondary metabolites that play vital roles for their primary functions such as growth, defence, adaptations or reproduction. Some of the plant secondary metabolites are beneficial to mankind as nutraceuticals and pharmaceuticals. Metabolic pathways and their regulatory mechanism are crucial for targeting metabolite engineering. The clustered regularly interspaced short palindromic repeats (CRISPR)/Cas9-mediated system has been widely applied in genome editing with high accuracy, efficiency, and multiplex targeting ability. Besides its vast application in genetic improvement, the technique also facilitates a comprehensive profiling approach to functional genomics related to gene discovery involved in various plant secondary metabolic pathways. Despite these wide applications, several challenges limit CRISPR/Cas system applicability in genome editing in plants. This review highlights updated applications of CRISPR/Cas system-mediated metabolic engineering of plants and its challenges.

Pomegranate juice fermented by tannin acyl hydrolase and Lactobacillus vespulae DCY75 enhance estrogen receptor expression and anti-inflammatory effect

Phenolics are phytochemicals in plants, fruits, and vegetables have potential health-promoting efficacies. However, mostly available as a complex form. So, to increase the contents and nutritional value of the phenolic compounds, fermentation is most readily used in the food industry. Especially, the hydrolyzable tannins present in the pomegranate that can be liberated into monomolecular substances, which enhances biological activity. Thus, this study aims to convert hydrolyzable tannins to ellagic acid by fermentation using Tannin acyl hydrolase (TAH) and a novel bacteria strain Lactobacillus vespulae DCY75, respectively to investigate its effect on Estrogen receptor alpha (ERα) and estrogen receptor beta (ERβ) mRNA expression along with inflammation inhibition. As a result, the fermentation enhanced the ellagic acid content up to 70% by the synergetic effect of TAH and DCY75. Furthermore, fermented pomegranate (PG-F) increased cellular proliferation as well as upregulated the gene expression of estrogen regulators such as ERα, ERβ, and pS2 in breast cancer cell line (MCF-7), which commonly used to evaluate estrogenic activity. Moreover, to study the inflammation associated with low estrogen in menopause, we have analyzed the inhibition of nitric oxide (NO)/inducible nitric oxide synthase (iNOS) in RAW 264.7 cells. The PG-F juice did not exert any cytotoxicity in RAW 264.7 cells and inhibited NO production along with the downregulation of a major pro-inflammatory cytokine iNOS which indicates the anti-inflammatory potential of it. To sum it up, the fermented commercial pomegranate juice using a novel bacteria strain increased the amount of ellagic acid that the value added bioactive of pomegranate and it has significantly increased the estrogenic activity via upregulating estrogen related biomarkers expression and reduced the risk of related inflammation via NO/iNOS inhibition. This study could be a preliminary study to use fermented pomegranate as a potential health functional food after further evaluation.

High-Intensity Ultrasound Processing Enhances the Bioactive Compounds, Antioxidant Capacity and Microbiological Quality of Melon (Cucumis melo) Juice

The bioactive compounds, antioxidant capacity and microbiological quality of melon juice processed by high-intensity ultrasound (HIUS) were studied. Melon juice was processed at two ultrasound intensities (27 and 52 W/cm2) for two different processing times (10 and 30 min) using two duty cycles (30 and 75%). Unprocessed juice was taken as a control. Total carotenoids and total phenolic compounds (TPC) were the bioactive compounds analyzed while the antioxidant capacity was determined by DPPH, ABTS and FRAP assays. The microbiological quality was tested by counting the aerobic and coliforms count as well as molds and yeasts. Total carotenoids increased by up to 42% while TPC decreased by 33% as a consequence of HIUS processing regarding control juice (carotenoids: 23 μg/g, TPC: 1.1 mg GAE/g), gallic acid and syringic acid being the only phenolic compounds identified. The antioxidant capacity of melon juice was enhanced by HIUS, achieving values of 45% and 20% of DPPH and ABTS inhibition, respectively, while >120 mg TE/100 g was determined by FRAP assay. Further, the microbial load of melon juice was significantly reduced by HIUS processing, coliforms and molds being the most sensitive. Thus, the HIUS could be an excellent alternative supportive the deep-processing of melon products.

GC-MS and LC-TOF-MS profiles, toxicity, and macrophage-dependent in vitro anti-osteoporosis activity of Prunus africana (Hook f.) Kalkman Bark

Osteoporosis affects millions of people worldwide. As such, this study assessed the macrophage-dependent in vitro anti-osteoporosis, phytochemical profile and hepatotoxicity effects in zebrafish larvae of the stem bark extracts of P. africana. Mouse bone marrow macrophages (BMM) cells were plated in 96-well plates and treated with P. africana methanolic bark extracts at concentrations of 0, 6.25, 12.5, 25, and 50 µg/ml for 24 h. The osteoclast tartrate-resistant acid phosphatase (TRAP) activity and cell viability were measured. Lipopolysaccharides (LPS) induced Nitrite (NO) and interleukin-6 (IL-6) production inhibitory effects of P. africana bark extracts (Methanolic, 150 µg/ml) and β-sitosterol (100 µM) were conducted using RAW 264.7 cells. Additionally, inhibition of IL-1β secretion and TRAP activity were determined for chlorogenic acid, catechin, naringenin and β-sitosterol. For toxicity study, zebrafish larvae were exposed to different concentrations of 25, 50, 100, and 200 µg/ml P. africana methanolic, ethanolic and water bark extracts. Dimethyl sulfoxide (0.05%) was used as a negative control and tamoxifen (5 µM) and dexamethasone (40 µM or 80 µM) were positive controls. The methanolic P. africana extracts significantly inhibited (p < 0.001) TRAP activity at all concentrations and at 12.5 and 25 µg/ml, the extract exhibited significant (p < 0.05) BMM cell viability. NO production was significantly inhibited (all p < 0.0001) by the sample. IL-6 secretion was significantly inhibited by P. africana methanolic extract (p < 0.0001) and β-sitosterol (p < 0.0001) and further, chlorogenic acid and naringenin remarkably inhibited IL-1β production. The P. africana methanolic extract significantly inhibited RANKL-induced TRAP activity. The phytochemical study of P. africana stem bark revealed a number of chemical compounds with anti-osteoporosis activity. There was no observed hepatocyte apoptosis in the liver of zebrafish larvae. In conclusion, the stem bark of P. africana is non-toxic to the liver and its inhibition of TRAP activity makes it an important source for future anti-osteoporosis drug development.

Phoenix dactilyfera L. Pits Extract Restored Bone Homeostasis in Glucocorticoid-Induced Osteoporotic Animal Model through the Antioxidant Effect and Wnt5a Non-Canonical Signaling

Oxidative stress associated with long-term glucocorticoids administration is a route through which secondary osteoporosis can be developed. The therapeutic potential of Phoenix dactilyfera L. pits is offered by their balanced, valuable and diverse phytochemical composition providing protective potential against oxidative reactions, making it a good candidate to treat glucocorticoid-induced osteoporosis (GIO). This study evaluates the possible anti-osteoporotic effect of date pit extract (DPE) against dexamethasone (DEXA)-induced osteoporosis. Male rats were allocated into three control groups, which received saline, low and high doses of DPE (150 and 300 mg/kg/day), respectively. Osteoporosis-induced groups that received DEXA (1 mg/kg/day) were divided into DEXA only, DPE (2 doses) + DEXA, and ipriflavone + DEXA. Femoral bone minerals density and bone mineral content, bone oxidative stress markers, Wnt signaling, osteoblast and osteoclast differentiation markers, and femur histopathology were evaluated. DPE defeated the oxidative stress, resulting in ameliorative changes in Wnt signaling. DPE significantly reduced the adipogenicity and abolished the osteoclastogenic markers (RANKL/OPG ratio, ACP, TRAP) while enhancing the osteogenic differentiation markers (Runx2, Osx, COL1A1, OCN). In Conclusion DPE restored the balanced proliferation and differentiation of osteoclasts and osteoblasts precursors. DPE can be considered a promising remedy for GIO, especially at a low dose that had more potency.

Effect of basal medium on growth and polyphenols accumulation by Gardenia jasminoides Ellis cell suspension

The goal of this study was to analyze the effect of different medium bases on accumulation of biomass and secondary metabolites production by Gardenia jasminoides Ellis. cell suspension culture. The result revealed that different media have significant effect on biomass accumulation and production of polyphenol compounds. HPLC analyses showed that the higher polyphenol content was achieved when the cells were cultivated on McCOWN Woody plant Medium (WP) media for 14 days on darkness, at 24°C. At this conditions, the cells produced maximal amounts of catechin (24.44±2.46 µg/g DW), chlorogenic acid (20.26 ±3.68 µg/g DW), epicatechin (70.44±7.46 µg/g DW) and rutin (45.90±0.26 µg/g DW). Both MS and WP media were optimal for biomass accumulation. When cultivated on these media, Gardenia cells accumulated maximal amount of dry biomass ADB = 0.99±0.1g/100ml and ADB = 0.93±0.04 g/100ml for МS and WP, respectively. The corresponding growth indexes were GIDW = 1.68±0.2 on MS and GIDW = 1.58±0.07 on WP medium. The reported results are the first step of future optimization of the nutrient medium composition and cultivation conditions essential for the scale -up of cultivation process of G. jasminoides cell suspension culture for mass production of polyphenolic compounds.

Syringic acid demonstrates promising protective effect against tau fibrillization and cytotoxicity through regulation of endoplasmic reticulum stress-mediated pathway as a prelude to Alzheimer's disease

There are several studies reporting that different plant-based metabolites are potential inhibitors of protein amyloid fibrillation. As chemical features of metabolites can regulate protein aggregation process, in the present in vitro investigation, tau protein was selected as a model of Alzheimer's disease to elaborate the inhibitory effect of syringic acid (SA) on its assembly and associated neurotoxicity in aggregation conditions. Extrinsic fluorescence, Congo red adsorption, and CD spectroscopic studies, TEM, size-exclusion chromatography, and MALDI-TOF mass spectrometry analysis along with MTT and qRT-PCR assays were performed to assess the inhibitory effects of SA against tau aggregation and neurotoxicity. It was shown that SA has the tendency to control the aggregation of the tau proteins through modulating the amyloid kinetic parameters, exposure of hydrophobic residues, and structural changes. Moreover, the structures formed in the presence of SA recovered the viability of neuron-like cells (SH-SY5Y) through regulation of endoplasmic reticulum stress signaling pathway by downregulation of ATF-6, caspase-8 and caspase-3 mRNA. In conclusion, it can be suggested that SA may be used as a potential small molecule in the development of therapeutic platforms against Alzheimer's disease.

Simultaneous determination of four phenolic acids in traditional Chinese medicine by capillary electrophoresis-chemiluminescence

Chlorogenic, ferulic, vanillic, and caffeic acids are phenolic acids found in natural drugs. They possess the biological activities of scavenging free radicals and inhibiting thrombus formation. Phenolic acids can inhibit the oxidation of low-density lipoprotein, as well as have anti-inflammatory effects. This paper reports for the first time a capillary electrophoresis-chemiluminescence (CE-CL) method for the simultaneous determination of the four phenolic acids found in traditional and proprietary Chinese medicine, including Lycium chinense Miller, Shuanghuanglian oral liquid, and Taraxacum mongolicum granules. Capillary electrophoretic separation was performed on a self-assembled CE-CL device with an uncoated fused-silica capillary (66 cm effective length, 50 μm i.d.), and the background electrolyte was composed of 3.0 × 10-5 M Ag(iii) (pH = 12.01), 3.0 mM luminol (pH = 9.20), and 10 mM sodium tetraborate solution. The injection time was 12 s (under gravity) and the separation voltage was 22 kV. The combination of solid-phase extraction (SPE) and CE-CL improves the sensitivity. Under optimal conditions, calibration graphs displayed a linear range between 0.625 and 20.0, 1.000 and 30.0, 0.150 and 1.50, and 0.045 and 1.00 μg mL-1 for chlorogenic, ferulic, vanillic, and caffeic acid, respectively. The detection limit ranged from 0.014 to 0.300 μg mL-1. The practicality of using the proposed method to determine the four target analytes in traditional Chinese medicine was also validated, in which recoveries ranged from 90.9% to 119.8%. Taken together, these results indicate that the developed method is sensitive and reliable. Furthermore, the method was successfully applied to real traditional Chinese medicine samples.

Dietary syringic acid reduces fat mass in an ovariectomy-induced mouse model of obesity

OBJECTIVE

Postmenopausal women are at increased risk of metabolic diseases such as obesity and diabetes. Therefore, the chemoprevention of postmenopausal changes in health via dietary supplements is important. Syringic acid (SA) is a phenolic compound present in the fruit of the assai palm, Euterpe oleracea, and in the mycelium of the shiitake mushroom, Lentinula edodes. This compound shows no affinity for estrogen receptors and may exert disease-preventive effects. Reportedly, dietary SA ameliorates high-fat diet-induced obesity in mice; however, its effects on estrogen deficiency-induced obesity are still unclear. Therefore, in this study, we investigated whether and how dietary SA affects these factors in ovariectomized (OVX) mice.

METHODS

Ten-week-old OVX mice were fed SA-containing diets (100 mg/kg body weight/d) for 12 weeks. Their body weights, food intake, and uterus weights as well as other parameters were measured and comparisons were made with mice in the control group.

RESULTS

Dietary SA did not affect the body weight, food intake, or uterus weight of OVX mice over the study period; however, the SA-fed group showed lower fat mass (ie, visceral, subcutaneous, and total fat) than the OVX-control group (11.1 ± 3.3 vs. 8.3 ± 2.4, P < 0.05; 7.9 ± 1.1 vs. 5.9 ± 1.6, P < 0.05; 19.0 ± 4.2 vs. 14.1 ± 3.8, P < 0.05, respectively). Furthermore, blood analysis revealed that SA-treatment resulted in a dose-dependent decrease and increase in serum triglyceride (59.2 ± 8.3 vs. 43.9 ± 12.2 mg/dL P < 0.05) and adiponectin (7.7 ± 0.3 vs. 9.5 ± 0.6 μg/mL, P < 0.05) levels, respectively.

CONCLUSIONS

These results suggest that the SA diet improves lipid metabolism without affecting the uterus in OVX mice. Therefore, dietary SA has potential applicability for the prevention of postmenopausal obesity and type 2 diabetes.

Bioactive components of mushrooms: Processing effects and health benefits

Mushrooms have been recognized for their culinary attributes for long and were relished in the most influential civilizations in history. Currently, they are the focus of renewed research because of their therapeutic abilities. Nutritional benefits from mushrooms are in the form of a significant source of essential proteins, dietary non-digestible carbohydrates, unsaturated fats, minerals, as well as various vitamins, which have enhanced its consumption, and also resulted in the development of various processed mushroom products. Mushrooms are also a crucial ingredient in traditional medicine for their healing potential and curative properties. The literature on the nutritional, nutraceutical, and therapeutic potential of mushrooms, and their use as functional foods for the maintenance of health was reviewed, and the available literature indicates the enormous potential of the bioactive compounds present in mushrooms. Future research should be focused on the development of processes to retain the mushroom bioactive components, and valorization of waste generated during processing. Further, the mechanisms of action of mushroom bioactive components should be studied in detail to delineate their diverse roles and functions in the prevention and treatment of several diseases.

Non-flavonoid polyphenols in osteoporosis: preclinical evidence

The development of progressive osteopenia and osteoporosis (OP) is due to the imbalance between bone resorption and bone formation, determining a lower bone resistance, major risks of fractures, with consequent pain and functional limitations. Flavonoids, a class of polyphenols, have been extensively studied for their therapeutic activities against bone resorption, but less attention has been given to a whole series of molecules belonging to the polyphenolic compounds. However, these classes have begun to be studied for the treatment of OP. In this systematic review, comprehensive information is provided on non-flavonoid polyphenolic compounds, and we highlight pathways implicated in the action of these molecules that act often epigenetically, and their possible use for OP treatment and prevention.

A comprehensive review on phenolic compounds from edible mushrooms: Occurrence, biological activity, application and future prospective

Phenolic compounds are minor metabolites usually present in mushroom species. Because of their potential advantages for human health, such as antioxidant and other biological activities, these bioactive components have been gaining more interest as functional foods, nutraceutical agents for providing better health conditions. This review aims to comprehensively discuss the recent advances in mushroom phenolic compounds, including new sources, structural characteristics, biological activities, potential uses and its industrial applications as well as the future perspectives. Phenolic acids as well as flavonoids are considered the most common phenolics occurring in mushroom species. These are responsible for its bioactivities, including antioxidant, anti-inflammatory, antitumor, antihyperglycaemic, antiosteoporotic, anti-tyrosinase and antimicrobial activities. Several edible mushroom species with good phenolic content and show higher biological activity were highlighted, in a way for its futuristic applications. Trends on mushroom research highlighting new research areas, such as nanoformulation were discussed. Furthermore, the use of phenolic compounds as nutraceutical and cosmeceutical agents as well as the future perspectives and recommendations were made.

Syringic Acid Alleviates Cesium-Induced Growth Defect in Arabidopsis

Syringic acid, a phenolic compound, serves a variety of beneficial functions in cells. Syringic acid increases in plants in response to cesium, and exogenous application of syringic acid resulted in a significant attenuation of cesium-induced growth defects in Arabidopsis. In addition, cesium or syringic acid application to plants also resulted in increased lignin deposition in interfascicular fibers. To better understand the role of lignin and syringic acid in attenuating cesium-induced growth defects, two mutants for Arabidopsis REDUCED EPIDERMAL FLUORESCENE 4 (REF4) and fourteen laccase mutants, some of which have lower levels of lignin, were evaluated for their response to cesium. These mutants responded differently to cesium stress, compared to control plants, and the application of syringic acid alleviated cesium-induced growth defects in the laccase mutants but not in the ref4 mutants. These findings imply that lignin plays a role in cesium signaling but the attenuation of cesium stress defects by syringic acid is mediated by regulatory components of lignin biosynthesis and not lignin biosynthesis itself. In contrast, syringic acid did not alleviate any low potassium-induced growth defects. Collectively, our findings provide the first established link between lignin and cesium stress via syringic acid in plants.