Phenolic Compositions and Antioxidant Properties in Bark, Flower, Inner Skin, Kernel and Leaf Extracts of Castanea crenata Sieb. et Zucc

Promising Support Coming from Nature: Antioxidant and Anti-Inflammatory Potential of Castanea sativa Wood Distillate on Skin Cells

Tissue homeostasis, function recovery, and protection mechanisms are boosted by the balanced and timely control of inflammation and oxidative stress. Nowadays, many natural products and bio-derivates exhibit antioxidant and anti-inflammatory activity, supporting medical care and tissue wellness against inflammation, oxidative stress, and inflammaging. Castanea sativa wood distillate (WD) is a bio-derivative used as a corroborant and biofertilizer in agriculture. Based on the safety profile of low concentrations of WD on human cells, the present study aims to assess the anti-inflammatory and antioxidant activity of WD on different cell types in the integumentary system. Human keratinocytes, mucosal epithelium, dermal fibroblasts, and endothelial cells were exposed to WD, and the concentrations devoid of pro-apoptotic potential were profiled. Then, the effect of nontoxic doses of WD revealed an anti-inflammatory effect, observed through the immunodetection of prostanoid cascade markers in experimentally induced inflammation. A reduction in endothelial hyperpermeability was evidenced by the immunofluorescence analysis of cell-cell adhesion proteins, VE-cadherin and ZO-1. In addition, WD buffered the exogenously produced oxidative stress. On the whole, WD showed both anti-inflammatory and antioxidant activities on the various cell types, preserving endothelial barrier integrity. Overall, this study supports the involvement of this bio-derivative in novel exploitable fields, such as therapeutic dermatological applications for human and animal medical care.

Phenolic Composition and Bioactivities of Invasive Ailanthus altissima (Mill.) Swingle Leaf Extracts Obtained by Two-Step Sequential Extraction

Ailanthus altissima, a highly invasive species, contains valuable compounds in different plant parts, indicating great practical potential. This paper proposes the use of non-polar (n-hexane) and polar (ethanol) solvents for the extraction of antioxidant compounds from A. altissima (family Simaroubaceae) leaves in a sequential two-step process. Fresh and dried leaves were examined for their microstructure by scanning electron microscopy, and for color changes in the CIELAB color space co-ordinates. An investigation of the harvesting season, processing (freezing and drying), and solvent indicates ethanol can be used for the highly efficient extraction of phenolics, flavonoids, tannins, and carotenoids. Statistically significant differences were found between the autumn and summer samples for phenolic content, and between dried and frozen samples for tannin content. The HPLC phenolic profile indicates more phenolics (nine polyphenols) in dried leaves harvested in both seasons compared to those in frozen ones (five to six polyphenols). Frozen leaves showed a higher antioxidant activity in a ferric-reducing antioxidant power assay than that of the dried samples, which exhibited a higher antioxidant activity using the 1, 1-diphenyl-2-picryl-hydrazyl assay, but it was not statistically significant. The phenolic, flavonoid, and carotenoid contents significantly influenced the antioxidant activities. Among the ethanolic extracts, those from dried leaves showed better antibacterial activity, in particular, on Staphylococcus aureus and Enterococcus faecalis. The high bioactive content and activity of A. altissima leaves make them suitable natural raw materials for various applications.

Phytotoxic and Cytotoxic Effects, Antioxidant Potentials, and Phytochemical Constituents of Stevia rebaudiana Leaves

Stevia (Stevia rebaudiana), recognized for its low-calorie, sugar-free attributes, and various health benefits, has potential applications beyond human consumption, particularly in agriculture. This study explored the potential uses of Stevia in both agricultural and healthcare contexts by examining its plant-inhibitory, cytotoxic, and antioxidant effects. The methanolic extract of Stevia leaves was fractionated into hexane, ethyl acetate, chloroform, and water fractions. These fractions were then subjected to the bioassay analyses above and underwent identification of their chemical constituents. The results indicated that the ethyl acetate fraction demonstrated significant inhibitory effects on weed germination and growth of Beggars tick (Bidens frondosa) (100% inhibition at 1000 ppm of dose). This fraction also exhibited the highest antioxidant activity, total phenolic, and total flavonoid contents (IC50 DPPH = 18.67 μg/mL, 103.50 mg GAE/g fraction, and 410.16 mg QE/g fraction, respectively). In contrast, the chloroform fraction showed the highest cytotoxic effect (LC50 = 700.01 ppm) in the brine shrimp (Artemia salina) mortality evaluation. Pearson's correlation analysis revealed a positive correlation among plant inhibitory effects, antioxidant potentials, and phenolic/flavonoid contents of Stevia. FTIR spectra confirmed the presence of phenols and nonpolar components in the ethyl acetate and chloroform fractions. In addition, GC-MS analysis successfully identified Stevia's key constituents, including tetracontane, hexadecane, hexadecanoic acid, methyl ester in the ethyl acetate fraction, and spiro [4.5] decan-7-one and 6-hydroxy-4,4,7a-trimethyl-5,6,7,7a-tetrahydrobenzofuran-2(4H)-one in the chloroform fraction. This study underscores the potential of S. rebaudiana as a source of natural antioxidants and herbicides, offering valuable insights into its diverse applications in agriculture.

Tissue-specific variations of piperine in ten populations of Piper longum L.: bioactivities and toxicological profile

P. longum L., one of the most significant species of the genus Piperaceae, is most frequently employed in Indian-Ayurvedic and other traditional medicinal-systems for treating a variety of illnesses. The alkaloid piperine, is the key phytoconstituent of the plant, primarily responsible for its' pharmacological-impacts. The aim of the study is to analyse the intra-specific variation in piperine content among different chemotypes (PL1 to PL 30) and identify high piperine yielding chemotype (elite-chemotype) collected from 10 different geographical regions of West Bengal by validated HPTLC chromatography method. The study also focused on the pharmacological-screening to better understand the antioxidant activity of the methanol extracts of P. longum by DPPH and ABTS radical-scavenging activity and genotoxic activity by Allium cepa root tip assay. It was found that the P. longum fruit chemotypes contain high amount piperine (highest 16.362 mg/g in chemotype PL9) than the stem and leaf chemotypes. Both DPPH and ABTS antioxidant assays revealed that P. longum showed moderate radical-scavenging activity and the highest activity was found in PL9 (fruit) chemotype with IC50 values of 124.2 ± 0.97 and 104 ± 0.78 µg/ml respectively. The A. cepa root tip assay showed no such significant genotoxic-effect and change in mitotic-index. The quick, reproducible, and validated HPTLC approach offers a useful tool for determining quantitative variations of piperine among P. longum chemotypes from different geographical-regions and also according to the different tissues and choose elite genotypes with high piperine production for continued propagation and commercialization for the pharmaceutical sector. Additionally, the plant's in-vitro antioxidant property and lack of genotoxicity directly supports its' widespread and long history of use as a medicinal and culinary plant.

Effect of Adding Chestnut Inner Skin on Allergenic Protein, Antioxidant Properties, and Quality of Bread

Wheat-dependent, exercise-induced anaphylaxis has no fundamental cure and requires patients to refrain from wheat consumption or to rest after eating. Although hypoallergenic wheat production by enzymatic degradation or thioredoxin treatment has been investigated, challenges still exist in terms of labor and efficacy. We investigated a hypoallergenic wheat product manufacturing technology that takes advantage of the property of tannins to bind tightly to proteins. Commercially available bread wheat (BW) and hypoallergenic wheat (1BS-18 "Minaminokaori", 1BS-18M) were used. Chestnut inner skin (CIS) was selected as a tannin material based on the screening of breads with added unused parts of persimmon and chestnut. Hypoallergenicity was evaluated using Western blotting. The effect of CIS addition on the antioxidative properties of bread was also measured. For both BW and 1BS-18M, CIS addition reduced the immunoreactivity of wheat allergens. Antioxidant activities increased with increasing CIS substitution. However, 10% CIS-substituted breads were substantially less puffy. Five percent CIS substitution was optimal for achieving low allergenicity, while maintaining bread quality. The strategy investigated herein can reduce allergies related to wheat bread consumption. In this study, the evaluation of hypoallergenicity was limited to instrumental analysis. In the future, we will evaluate hypoallergenicity through clinical trials in humans.

Antioxidant and in vitro cosmeceutical activities of chestnut inner shell fermented by Monascus kaoliang

Chestnut inner shell (CIS) was fermented at 30 °C for 12 day using Monascus kaoliang, either in solid or submerged state, and alcohol extracts (70% ethanol) of the fermented CIS were examined for their antioxidant (total phenol content and diphenylpicrylhydrazyl radical scavenging activity) and in vitro cosmeceutical activities (tyrosinase and elastase inhibitory activities). Both activities were significantly increased by the M. kaoliang-fermentation, more apparently by submerged fermentation (SMF) than by solid-state fermentation (SSF). The cosmeceutical activity reached its maximum value on the 3rd day of fermentation. The residual amounts of phenolic acids and catechins in the CIS extracts were increased by the fermentation, up to 395.0 and 344.3 µg/g, respectively. More phenolic acids were produced by SMF than SSF, whereas more catechins were produced by SSF than SMF. Therefore, SMF using M. kaoliang was an efficient process for the utilization of CIS as a source of cosmeceuticals.

Therapy-resistant breast cancer in focus: Clinically relevant mitigation by flavonoids targeting cancer stem cells

Significant limitations of the reactive medical approach in breast cancer management are clearly reflected by alarming statistics recorded worldwide. According to the WHO updates, breast malignancies become the leading cancer type. Further, the portion of premenopausal breast cancer cases is permanently increasing and demonstrates particularly aggressive patterns and poor outcomes exemplified by young patients with triple-negative breast cancer that lacks targeted therapy. Accumulating studies suggest the crucial role of stem cells in tumour biology, high metastatic activity, and therapy resistance of aggressive breast cancer. Therefore, targeting breast cancer stem cells is a promising treatment approach in secondary and tertiary breast cancer care. To this end, naturally occurring substances demonstrate high potential to target cancer stem cells which, however, require in-depth analysis to identify effective anti-cancer agents for cost-effective breast cancer management. The current article highlights the properties of flavonoids particularly relevant for targeting breast cancer stem cells to mitigate therapy resistance. The proposed approach is conformed with the principles of 3P medicine by applying predictive diagnostics, patient stratification and treatments tailored to the individualised patient profile. Expected impacts are very high, namely, to overcome limitations of reactive medical services improving individual outcomes and the healthcare economy in breast cancer management. Relevant clinical applications are exemplified in the paper.

Dermal Papilla Cell Proliferation of Phytochemicals Isolated from Chestnut Shells (Castanea crenata)

Castanea crenata (Fagaceae) is a species of chestnut tree that is endemic to the Republic of Korea and Japan. While its kernels are consumed, chestnut by-products such as shells and burs, which account for 10-15% of the total weight, are discarded as waste. Phytochemical and biological studies have been carried out to eliminate this waste and develop high-value products from its by-products. In this study, five new compounds (1-2, 6-8) along with seven known compounds were isolated from the shell of C. crenata. This is the first study to report diterpenes from the shell of C. crenata. Comprehensive spectroscopic data including 1D, 2D NMR, and CD spectroscopy were used to determine the compound structures. All isolated compounds were examined for their ability to stimulate dermal papilla cell proliferation using a CCK-8 assay. In particular, 6β,7β,16α,17-Tetrahydroxy-ent-kauranoic acid, isopentyl-α-L-arabinofuranosyl-(1→6)-β-D-glucopyranoside, and ellagic acid exhibited the most potent proliferation activity of all.

Isolation and Identification of Constituents Exhibiting Antioxidant, Antibacterial, and Antihyperuricemia Activities in Piper methysticum Root

The aqueous extract of kava (Piper methysticum) root is known as a traditional beverage for daily intake in the Western Pacific Islands, such as Fiji, Tonga, and Vanuatu, to induce relaxation and health-beneficial effects. In this study, the antioxidant, anti-hyperuricemia, and antibacterial properties of kava root were investigated through the isolation and purification of bioactive compounds in ten fractions separated by column chromatography (CC). They included six flavonoids, 5-hydroxy-4',7-dimethoxyflavanone (C1), matteucinol (C2), isosakuranetin (C3), 5,7- dimethoxyflavanone (C4), 2',4'-dihydroxy-6'-methoxydihydrochalcone (in MC5) and alpinetin (C10), and seven kavalactones, 5,6-dehydrokawain (DK) (in MC5 and C6), kavain (in MC7), yangonin (in MC7 and C8), dihydro-5,6-dehydrokavain (DDK) (in MC9), 7,8-dihydromethysticin (in MC9), dihydromethysticin (in MC9), methysticin (in MC9). The chemical structures of the compounds were illustrated by the analyses of gas chromatography-mass spectrometry (GC-MS), electrospray ionization-mass spectrometry (ESI-MS), nuclear magnetic resonance (¹H and ¹³C-NMR), and X-ray diffraction. The evaluation of the free radical scavenging activity of the isolated substances via the DPPH and ABTS assays revealed that C3 (IC₅₀: ABTS = 76.5; DPPH = 74.8 µg/mL) possessed the strongest antioxidant property. In terms of anti-hyperuricemia activity evaluated via the xanthine oxidase inhibitory in vitro assay, the compound C10 was the most promising inhibitor, revealing an IC₅₀ of 134.52 µg/mL. The two kavalactone mixtures in MC5 and a pure compound C6 inhibited the growth of bacteria Listeria monocytogenes, while MC7 can constrain the development of Klebsiella pneumoniae. This is the first study to isolate, purify, and identify the flavonoids isosakuranetin, 2',4'-dihydroxy-6'-methoxydihydrochalcone and alpinetin in kava root and report their pharmaceutical potential. The identified bioactive compounds showed potent antioxidant, anti-hyperuricemia, and antibacterial activity and thus can enhance the value of beverages and foods derived from kava root.

Herbal Therapy for the Treatment of Seborrhea Dermatitis

Seborrhea dermatitis is a skin disorder that usually appears on parts of the body that have high density of sebaceous glands, such as the face, chest, and scalp. Clinical manifestations that generally appear as scaly skin and erythema. Seborrhea dermatitis is also known as one of the causes of alopecia. Treatments that can be used for seborrhea dermatitis are antifungal, anti-inflammatory, keratolytic, and coal tar. There are concerns about poor adherence, resistance, and some side effects of drugs that have been used in the treatment of seborrhea dermatitis. Concerns regarding these issues increase the urgency for the development of new therapeutic agents in the treatment of seborrhea dermatitis. Research on medicinal plants has enormous potential to produce compounds with new structures and bioactivity. This review discusses clinical and in vitro studies related to the activity of several medicinal plants that have potential as a treatment for seborrhea dermatitis, as well as the compounds that play a role in these activities. Literature searches were carried out on the PubMed, Taylor & Francis, and SpringerLink databases using Boolean Operators to get 25 articles that match the keywords used. Of the 25 articles, six were clinical trials, while 19 were in vitro studies of Malassezia. Several plants have potential as promising therapeutic agents for the treatment of seborrhea dermatitis by inhibiting the growth of Malassezia, decreasing sebum secretion, and decreasing symptoms associated with seborrhea dermatitis such as itching, pain or burning sensation, and redness.

Polyphenol and Tannin Nutraceuticals and Their Metabolites: How the Human Gut Microbiota Influences Their Properties

Nutraceuticals have been receiving increasing attention in the last few years due to their potential role as adjuvants against non-communicable chronic diseases (cardiovascular disease, diabetes, cancer, etc.). However, a limited number of studies have been performed to evaluate the bioavailability of such compounds, and it is generally reported that a substantial elevation of their plasma concentration can only be achieved when they are consumed at pharmacological levels. Even so, positive effects have been reported associated with an average dietary consumption of several nutraceutical classes, meaning that the primary compound might not be solely responsible for all the biological effects. The in vivo activities of such biomolecules might be carried out by metabolites derived from gut microbiota fermentative transformation. This review discusses the structure and properties of phenolic nutraceuticals (i.e., polyphenols and tannins) and the putative role of the human gut microbiota in influencing the beneficial effects of such compounds.

Anti-inflammatory effect of flavonoids from chestnut flowers in lipopolysaccharide-stimulated RAW 264.7 macrophages and acute lung injury in mice

ETHNOPHARMACOLOGICAL RELEVANCE

Chestnut flowers were one of the by-products during chestnut industrial processing. Chestnut (Castanea mollissima Blume) flower is rich in flavonoids and has been used as a traditional medicine to treat a variety of diseases including respiratory disorders for a long history.

AIM OF THE STUDY

The present study aims to investigate the potential anti-inflammatory effect of flavonoids from chestnut flower (FCF) in lipopolysaccharide (LPS)-treated RAW 264.7 cells and stimulated acute lung injury (ALI) in mice.

MATERIALS AND METHODS

HPLC-ESI-MS/MS was applied to identify flavonoids from Chestnut flower. The ROS content in cells and lung tissue was measured by flow cytometry. The malondialdehyde (MDA) content, superoxide dismutase (SOD) activity and glutathione (GSH) content in cells and bronchoalveolar lavage fluid (BALF) was analyzed by photometry. Furthermore, the level of pro-inflammatory factors was analyzed by ELISA, and the expression of inflammatory gene mRNA by fluorescence quantitative PCR. H&E staining was used to evaluate the degree of lung tissue injury in mice. MPO activity was used to measure the degree of neutrophil infiltration. Total protein content was detected by BCA method.

RESULTS

A total of forty-nine flavonoids compounds were tentatively identified in FCF by mass spectrometry analysis. The results of cell experiment suggested that FCF could alleviate oxidative injury via increasing SOD activity and GSH content, as well as inhibiting the production of intracellular ROS and MDA. FCF exerted its protective effect by suppressing the expression of both inducible nitric oxide synthase (iNOS) and cycooxygenase 2 (COX-2) to inhibit the synthesis of pro-inflammatory factors and cytokines, including NO, PGE2, TNF-α, IL-6 and IL-1β. Besides, FCF treatment could alleviate the thickening of alveolar wall and pulmonary congestion in LPS-treated ALI mice, and significantly inhibit the activity of myeloperoxidas (MPO) and the expression of cytokines in BALF.

CONCLUSIONS

FCF could ameliorate inflammation and oxidative stress in LPS-treated inflammation, resulting in an overall improvement in both macroscopic and histological parameters.

Metabolite Profiling of Chestnut (Castanea crenata) According to Origin and Harvest Time Using 1H NMR Spectroscopy

Chestnuts are an important food crop commonly used as a food ingredient due to their nutritional properties and potential health benefits. In Korea, chestnuts have been crossbred to develop cultivars with insect resistance and high productivity, producing multiple chestnut varieties. This study classified 17 Castanea crenata cultivars produced in Korea according to origin and harvest time and determined the metabolites in chestnut kernels using ¹H nuclear magnetic resonance spectroscopy. The 17 C. crenata cultivars were divided into four groups based on their geographic origin: Korean native, Korean hybrid, Japanese native, and Japanese hybrid. The cultivars were also divided into three groups depending on their harvest period: early-ripening cultivar, mid-ripening cultivar, and late-ripening cultivar. The partial least squares-discriminant analysis score plot revealed differences among the groups. Identified metabolites, including amino acids, organic acids, and sugars, contributed to discriminating the origin and harvest time of the C. crenata chestnut kernels. Significant differences were observed, mainly in amino acids, which suggests that the composition of amino acids is one factor influenced by both the origin and harvest time of C. crenata. These results are useful to both growers and breeders because they identify the nutritional and metabolic characteristics of each C. crenata cultivar.

The aqueous fraction of Castanea crenata inner shell extract reduces obesity and intramuscular lipid accumulation via induction of mitochondrial respiration and fatty acid oxidation in muscle

BACKGROUND

Skeletal muscle is responsible for free fatty acid (FFA) disposal via mitochondrial respiration and fatty acid oxidation (FAO). Obesity triggers high levels of circulating FFAs, which can cause intramuscular lipid (IMCL) deposition. Diverse phytochemicals, including crude Castanea crenata inner shell extract (CCE), have been shown to possess an anti-obesity effect.

PURPOSE

We aimed to demonstrate whether the aqueous fraction of CCE (ACCE) provides an anti-obesity effect with a decrease in plasma FFAs and reduces IMCL.

METHODS

High-fat-fed C57BL/6 mice received ACCE via water intake. A204 cells incubated with fatty acids were treated with ACCE. Lipid accumulation and mitochondrial metabolism were assessed using histological and molecular techniques.

RESULTS

ACCE possessed a notably higher gallic acid content than CCE among the constituents. ACCE-administered mice exhibited reduced plasma FFA levels, adiposity, and IMCL. Muscle lipotoxicity was suppressed, including apoptosis, ER stress, and inflammation. The anti-lipid effect of ACCE was observed with the induction of mitochondrial respiration and fatty acid oxidation in muscle.

CONCLUSIONS

ACCE increases mitochondrial respiration and FAO in skeletal muscle and protects muscle from IMCL and lipotoxicity, reducing plasma FFA and adiposity.

Cornus officinalis Sieb. et Zucc. Seeds as a Dietary Source of Ellagic Acid

Ellagic acid (EA), a natural food component, has been identified as a functional food because of its role in disease prevention. In our previous study on the chemical component of the seeds of Cornus officinalis Sieb. et Zucc., ellagitannins (ETs) were firstly isolated and identified; these compounds can yield EA by acidic hydrolysis. Therefore, to evaluate the seeds as a potential source of EA, the free and total EA contents of the seeds, sarcocarps, and barks were evaluated separately. The highest total EA content was found in seeds (14.51-21.58 mg/g), followed by the sarcocarp (1.97-4.51 mg/g) and bark (trace amounts). EA mainly existed as ET in both the seeds and sarcocarps, while a small portion existed in free form. The findings of this study prove that the seeds of C. officinalis are a rich source of EA. This study reports a unique EA profile of C. officinalis for the first time, which may assist in the selection of EA sources for use in research and for the food and pharmaceutical industries.

Biological Function of Plant Tannin and Its Application in Animal Health

Plant tannins are widely found in plants and can be divided into hydrolyzed tannins and condensed tannins. In recent years, researchers have become more and more interested in using tannin-rich plants and plant extracts in ruminant diets to improve the quality of animal products. Some research results show that plant tannins can effectively improve the quality of meat and milk, and enhance the oxidative stability of the product. In this paper, the classification and extraction sources of plant tannins are reviewed, as well as the biological functions of plant tannins in animals. The antioxidant function of plant tannins is discussed, and the influence of their structure on antioxidation is analyzed. The effects of plant tannins against pathogenic bacteria and the mechanism of action are discussed, and the relationship between antibacterial action and antioxidant action is analyzed. The inhibitory effect of plant tannins on many kinds of pathogenic viruses and their action pathways are discussed, as are the antiparasitic properties of plant tannins. The anti-inflammatory action of tannins and its mechanism are analyzed. The function of plant tannins in antidiarrheal action and its influencing factors are discussed. In addition, the effects of plant tannins as feed additives on animals and the influencing factors are reviewed in this paper to provide a reference for further research.

Nontargeted Metabolomics as a Screening Tool for Estimating Bioactive Metabolites in the Extracts of 50 Indigenous Korean Plants

Many indigenous Korean plants have been used in medicinal preparations and health-promoting foods. These plant species contain beneficial metabolites with various bioactivities, such as antioxidant and anti-inflammatory activities. Herein, we suggest a new screening strategy using metabolomics to explore the bioactive compounds in 50 Korean plants. Secondary metabolites were analyzed using UHPLC-LTQ-Orbitrap-MS/MS. The plant extracts were subjected to antioxidant and anti-inflammatory assays. We identified metabolites that contributed to bioactivities according to the results of bioassays and multivariate analyses. Using Pearson’s correlation, phenolics (e.g., casuarictin, 3-O-methylellagic acid) showed positive correlation with antioxidant activity, while biflavonoids (e.g., amentoflavone, rosbustaflavone) were correlated with nitric oxide (NO) inhibition activity. To compensate for the limitation of this new strategy, we further validated these by investigating three parts (branches, fruits, leaves) of Platycladus orientalis which showed high activities on both bioassays. Unlike the above observation, we identified significantly different metabolites from different parts, which was not the results of bioassays. In these validation steps, interestingly, biflavonoids (e.g., robustaflavone, sciadopitysin) contributed to both activities in P. orientalis. The findings of this work suggest that new strategy could be more beneficial in the identification of bioactive plant species as well as that of their corresponding bioactive compounds that impart the bioactivity.

Effect of in vitro digestion on chestnut outer-skin and inner-skin bioaccessibility: The relationship between biotransformation and antioxidant activity of polyphenols by metabolomics

Chestnut skin is rich in polyphenols that have been linked to health for their antioxidant activity. However, chestnut outer-skin extract (COE), chestnut inner-skin extract (CIE), and their digested products have different compositions of polyphenols, and therefore their antioxidant activities might differ as well. Here, we study the effect of in vitro digestion on their total phenol content, antioxidant capacity, and individual phenolic profile to clarify the relationship between biotransformation and antioxidant activity. Compared to undigested samples, total phenol content and antioxidant activity of digested chestnut outer-skin extract (DCOE) and digested chestnut inner-skin extract (DCIE) had significantly higher values. The changes of phenolic composition and antioxidant activity after digestion were mainly due to the anthocyanin biosynthesis involving glycosylation, acylation, methoxylation and their reverse processes. All these data suggest that as chestnut processing by-products, COE and CIE are raw material sources of antioxidant-rich active substances and need more sufficient utilization.

Evaluation of the Antioxidant Activity, Deodorizing Effect, and Antibacterial Activity of 'Porotan' Chestnut By-Products and Establishment of a Compound Paper

Chestnuts are widely cultivated for their edible portion (kernel), whereas the non-edible parts are discarded. To enable the utilization of the by-products of processed chestnuts, we separated them into green and brown burs, shells, inner skin, and leaves, and analyzed the bioactive properties of the ground components. We also created a composite paper, comprising the inner skin, and examined its deodorant properties. It was revealed that the inner skin had the highest functionality and showed potent antioxidant, antibacterial, and deodorant properties. Furthermore, when we produced a paper, containing 60% inner skin, and examined its deodorant properties, we found that it was highly effective in deodorizing ammonia and acetic acid gases. These results show that the inner skin of chestnuts is a promising material for developing hygiene and other products.

Diversity of Chemical Structures and Biosynthesis of Polyphenols in Nut-Bearing Species

Nuts, such as peanut, almond, and chestnut, are valuable food crops for humans being important sources of fatty acids, vitamins, minerals, and polyphenols. Polyphenols, such as flavonoids, stilbenoids, and hydroxycinnamates, represent a group of plant-specialized (secondary) metabolites which are characterized as health-beneficial antioxidants within the human diet as well as physiological stress protectants within the plant. In food chemistry research, a multitude of polyphenols contained in culinary nuts have been studied leading to the identification of their chemical properties and bioactivities. Although functional elucidation of the biosynthetic genes of polyphenols in nut species is crucially important for crop improvement in the creation of higher-quality nuts and stress-tolerant cultivars, the chemical diversity of nut polyphenols and the key biosynthetic genes responsible for their production are still largely uncharacterized. However, current technical advances in whole-genome sequencing have facilitated that nut plant species became model plants for omics-based approaches. Here, we review the chemical diversity of seed polyphenols in majorly consumed nut species coupled to insights into their biological activities. Furthermore, we present an example of the annotation of key genes involved in polyphenolic biosynthesis in peanut using comparative genomics as a case study outlining how we are approaching omics-based approaches of the nut plant species.

Bioactive phenolic components and potential health effects of chestnut shell: A review

Chestnut kernels are often used for direct consumption; or processed to produce marron glacé, chestnut purée, and gluten-free products, while chestnut by-products (inner shell and outer shell) are treated as waste residues. Many in vivo and in vitro studies have proved how chestnut shell extract functions as an antioxidant and exhibits anticancer, anti-inflammatory, antidiabetic, and anti-obesity activities. This review introduces the main components of phenolic compounds in chestnut shells, traditional and modern extraction methods, and reported potential health effects. The aim is to have a better understanding of the functional active ingredients in chestnut shells and their value-added uses, to increase understanding of future applications of this agricultural and sideline product in the food, pharmaceutical, and cosmetic industries. PRACTICAL APPLICATIONS: In recent years, chestnut shells have become a hot research topic because of their rich bioactive ingredients. Due to the large amount of phenolic compounds in chestnut shells and their potential health functions (antioxidant, anticancer, antibacterial, anti-inflammatory, hypoglycemic, and treatment of obesity), extracts of chestnut shells have high biological value in the treatment of diseases. Therefore, this review introduces the main components of phenolic compounds in chestnut shells, traditional and modern extraction methods, and the potential health effects of these compounds. The aim of this review is to better understand the functional, active ingredients in chestnut shells and their value-added uses, and to increase understanding of future applications of this agricultural and sideline product in the food, pharmaceutical, and cosmetic industries.

Antioxidant, Anti-tyrosinase, Anti-α-amylase, and Cytotoxic Potentials of the Invasive Weed Andropogon virginicus

Andropogon virginicus is an invasive weed that seriously threatens agricultural production and economics worldwide. In this research, dried aerial parts of A. virginicus were extracted, applying Soxhlet and liquid-liquid phase methods to acquire the total crude (T-Anvi), hexane (H-Anvi), ethyl acetate (E-Anvi), butanol (B-Anvi), and water (W-Anvi) extracts, respectively. In which, T-Anvi contains the highest total phenolic and flavonoid contents (24.80 mg gallic acid and 37.40 mg rutin equivalents per g dry weight, respectively). Via anti-radical (ABTS and DPPH), and reducing power assays, E-Anvi exhibits the most potent activities (IC₅₀ = 13.96, 43.59 and 124.11 µg/mL, respectively), stronger than butylated hydroxytoluene (BHT), a standard antioxidant, while the lipid peroxidation inhibitory effect of E-Anvi (LPI = 90.85% at the concentration of 500 µg/mL) is close to BHT. E-Anvi shows the most substantial inhibition (IC₅₀ = 2.58 mg/mL) on tyrosinase. Notably, α-amylase is significantly suppressed by H-Anvi (IC₅₀ = 0.72 mg/mL), over twice stronger than the positive control, palmitic acid. In the cytotoxic assay, E-Anvi is the strongest extract inhibiting K562 cells (IC₅₀ = 112.01 µg/mL). Meanwhile, T-Anvi shows the highest prevention on Meg-01 expansion (IC₅₀ = 91.40 µg/mL). Dominant compounds detected in E-Anvi by high-performance liquid chromatography-electrospray ionization-tandem mass spectrometry (HPLC-ESI-MS/MS) are identified as flavonoids. However, among four major compounds identified in H-Anvi by gas chromatography-mass spectrometry (GC-MS), palmitic acid and phytol are the most abundant compounds with peak areas of 27.97% and 16.42%, respectively. In essence, this is the first report describing that A. virginicus is a potential natural source of antioxidants, tyrosinase and α-amylase inhibitors, and anti-chronic myeloid leukemia (CML) agents which may be useful in future therapeutics as promising alternative medicines.

Amelioration by Idesia polycarpa Maxim. var. vestita Diels. of Oleic Acid-Induced Nonalcoholic Fatty Liver in HepG2 Cells through Antioxidant and Modulation of Lipid Metabolism

Idesia polycarpa Maxim. var. vestita Diels (I. polycarpa) is well known as an edible oil plant which contains abundant linoleic acid and polyphenols. The objective of this study was to maximize the by-product of defatted fruit of I. polycarpa. We found that the fraction D of ethyl acetate extract (EF-D) contained more polyphenols, which contribute to its strong antioxidant activity by antioxidant assays (DPPH, ABTS, and FRAP). Meanwhile, EF-D showed a significant lipid-lowering effect on oleic acid- (OA-) induced hepatic steatosis in HepG2 cells through enhancing antioxidant activity, reducing liver damage, and regulating lipid metabolism, antioxidant, and inflammation-related gene expression. The SOD and T-AOC levels significantly increased, but the levels of MDA, AST, and ALT decreased obviously when treated with EF-D. In general, EF-D improved the antioxidant enzyme activities and decreased the hepatic injury activities. Besides, treatment with EF-D for NAFLD influenced lipid metabolism and inflammation by activating PPARα which was associated with the increased expression of CPT1 and decreased expression of SCD, NF-κB, and IL-1. Moreover, EF-D improved the oxidative stress system through activation of the Nrf2 antioxidant signal pathways and upregulated its target genes of HO-1, NQO1, and GSTA2. The results highlighted the EF-D from the defatted fruit of I. polycarpa regarding lipid-lowering, proving it to be a potential drug resource of natural products for treating the nonalcoholic fatty liver disease (NAFLD).

Leaves and Spiny Burs of Castanea Sativa from an Experimental Chestnut Grove: Metabolomic Analysis and Anti-Neuroinflammatory Activity

Castanea sativa cultivation has been present in Mediterranean regions since ancient times. In order to promote a circular economy, it is of great importance to valorize chestnut groves' by-products. In this study, leaves and spiny burs from twenty-four Castanea trees were analyzed by 1H NMR metabolomics to provide an overview of their phytochemical profile. The Orthogonal Projections to Latent Structures Discriminant Analysis (OPLS-DA) performed on these data allowed us to distinguish 'Marrone' from 'Castagna', since the latter were generally more enriched with secondary metabolites, in particular, flavonoids (astragalin, isorhamnetin glucoside, and myricitrin) were dominant. Knowing that microglia are involved in mediating the oxidative and inflammatory response of the central nervous system, the potential anti-inflammatory effects of extracts derived from leaves and spiny burs were evaluated in a neuroinflammatory cell model: BV-2 microglia cells. The tested extracts showed cytoprotective activity (at 0.1 and 0.5 mg/mL) after inflammation induction by 5 µg/mL lipopolysaccharide (LPS). In addition, the transcriptional levels of IL-1β, TNF-α, and NF-kB expression induced by LPS were significantly decreased by cell incubation with spiny burs and leaves extracts. Taken together, the obtained results are promising and represent an important step to encourage recycling and valorization of chestnut byproducts, usually considered "waste".

Effects of Dietary Inclusion of Bilberry and Walnut Leaves Powder on the Digestive Performances and Health of Tetra SL Laying Hens

Simple Summary

In poultry, diet composition influences growth performance, egg production, as well as digestion. In this study, the effects of dietary additives obtained from bilberry and walnut leaves powder on the digestive performances of Tetra SL hens were evaluated by histologic and morphometric analyses of the intestinal mucosa as well as by the enzymatic activity measurements of alpha-amylase, invertase, maltase, and trypsin correlated with cecum microbiota.

Abstract

The purpose of this study was to examine the effects of dietary inclusion of two additives at the final concentration of 0.5% bilberry (E1) and 1% walnut (E2) leaves powder in the basal diet on digestive health of hens. A total number of 90 Tetra SL hens were divided into two experimental groups (E1 and E2) and one control group (C) consisting of 30 hens each. After four weeks, 10 hens of each group were sacrificed and tissue samples and intestinal content were taken from the duodenum, jejunum, and cecum in order to perform histological, enzymatic, and microbiota analyses. In groups E1 and E2, the histological analysis showed a significant increase of villus height, resulting probably in increased absorption of nutrients in duodenum and jejunum. A decrease in the specific activity of alpha-amylase and trypsin in E1 and E2 for both duodenum and jejunum compared to the control one was also recorded. In addition, the maltase and invertase specific activity in duodenum increased, a tendency that was kept for maltase but not for invertase in jejunum. The cecal microbiota of E1 and E2 individuals was characterized by an increase of Firmicutes and Lactobacilli and a decrease of Enterobacteriaceae. In conclusion, our results indicate that bilberry and walnut leaves additives in feed may improve the health status of the poultry gastrointestinal tract.

Natural Tannin Wood Extracts as a Potential Food Ingredient in the Food Industry

Wood extracts are one of the most important natural sources of industrially obtained tannins. Their use in the food industry could be one of the biggest (most important) recent innovations in food science as a result of their multiple (many) possible applications. The use of tannin wood extracts (TWEs) as additives directly added in foods or in their packaging meets an ever-increasing consumer demand for innovative approaches to sustainability. The latest research is focusing on new ways to include them directly in food, to take advantage of their specific actions to prevent individual pathological conditions. The present review begins with the biology of TWEs and then explores their chemistry, specific sensorial properties, and current application in food production. Moreover, this review is intended to cover recent studies dealing with the potential use of TWEs as a starting point for novel food ingredients.

Antioxidant and a-amylase Inhibitory Activities and Phytocompounds of Clausena indica Fruits

Background: Clausena indica fruit is commonly used for food ingredients and traditional medicines in tropical countries, however, information about its biological activities and chemical profiles has been inadequately reported. Methods: In this study, a bio-guided fractionation of antioxidants and α-amylase inhibitors from hexane (MH) and ethyl acetate (ME) extracts of C. indica fruit (pericarp and seed) was carried out. Eleven fractions from MH (D1–D11) and 17 fractions from ME (T1–T17) were obtained from column chromatography over silica gel, which were then examined for anti-radical capacity by 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2′-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) assays, and pancreatic α-amylase inhibition, a key enzyme linked to type 2 diabetes. Results: Of isolated fractions, the fraction T4 revealed the most potent anti-DPPH activity (IC50 = 0.13 mg/mL), whereas T2 exhibits the strongest ABTS cation scavenging ability (IC50 = 0.31 mg/mL). In the enzymatic assay, the fractions D3 and T4 significantly inhibit the α-amylase reaction with IC50 values of 0.34 and 0.86 mg/mL, respectively. Remarkably, α-amylase suppression of T4 is close to acarbose and over four times stronger than palmitic acid, which are the well-known α-amylase inhibitors (IC50 = 0.07 and 1.52 mg/mL, respectively). The active constituents from fractions were identified by gas chromatography-mass spectrometry (GC-MS). The results show that the fraction D3 contains five major compounds, which are grouped in five classes consisting of fatty acids, phenols, benzodioxoles, alcohols, and sesquiterpenes. Among them, palmitic acid is the most dominant compound (32.64%), followed by 2R-acetoxymethyl-1,3,3-trimethyl-4t-(3-methyl-2-buten-1-yl)-1t-cyclohexanol (16.69%). Whilst, six major compounds belonging to fatty acid and coumarin classes are identified in the fraction T4. The most abundant compound in T4 is dentatin (47.32%), followed by palmitic acid (15.11%). Conclusions: This is the first finding that C. indica fruit can be a promising source for the development of natural antioxidant and antidiabetic agents. Additionally, the outcome reveals that dentatin, a known natural antineoplastic agent, can be feasibly exploited from C. indica fruit.

Efficacy of N-Methyl-N-Nitrosourea Mutation on Physicochemical Properties, Phytochemicals, and Momilactones A and B in Rice

Attempts regarding the improvement and development of novel rice with better quality and higher productivity have been increasing. Among approaches, mutation is a direct alteration on the genome and considered as one of the most beneficial routes to acquire new beneficial traits in rice. An experiment was carried out to explore the effects of N-methyl-N-nitrosourea (MNU) mutation on the antioxidant activities, phytochemical compounds, and momilactones A (MA) and B (MB) in rice. Two rice cultivars, K1 (an original cultivar DT84) and K2 (mutated DT84), were examined. Antioxidant activities, phenolic compounds, and momilactones of the rice grain, husk, and straw portions were measured and quantified. Antioxidant activities were higher in grain and straw of K2, whereas K1 showed greater antioxidant activity in rice husk. Additionally, K2 displayed higher total phenolic contents (TPC) in grain and straw as well as lower of it in the husk, but these variations significantly differed only in the straw portion. An increase in total flavonoid contents (TFC) was observed in the husk of K1, while K2 significantly enhanced TFC in straw. Both MA and MB, two compounds obtaining antidiabetes, anticancer, antimicrobial, antigout, and antiobesity properties, were detected and quantified in grain, husk, and straw of K1 and K2 samples. Generally, the contents of MA were higher than MB in all tested portions of rice crop. MA and MB were higher in straw followed by those in husk and grain, respectively. K2 contained higher amounts of MA and MB in straw and husk, but lower contents in grain compared with those in K1. This study illustrates that MNU mutation can improve grain quality and enhance bioactive compounds in straw, husk, and grain of rice. This approach has the potential to develop functional foods from rice, and therefore help farmers in developing countries to improve value in rice production.

Free and Bound Phenolics of Buckwheat Varieties: HPLC Characterization, Antioxidant Activity, and Inhibitory Potency towards α-Glucosidase with Molecular Docking Analysis

Free and bound phenolic fractions from six buckwheat varieties were investigated for their compositions, antioxidant activities, and inhibitory effects on α-glucosidase. The results showed that different buckwheat varieties have significant differences in phenolic/flavonoid contents, and these contents were found in higher quantities in free form than in bound form. HPLC results revealed that rutin, quercetin, and kaempferol-3-O-rutinoside were the most abundant components in free and bound forms, whereas dihydromyricetin was found only in the bound form. Free phenolics showed higher antioxidant activities of DPPH, ABTS⁺, OH•, and FRAP than those of bound phenolics. Strong inhibitory effects against α-glucosidase by the free/bound phenolic fractions were found in all buckwheat varieties, and free phenolics showed stronger α-glucosidase inhibition than that of the corresponding bound phenolics. More importantly, the main phenolic compounds observed in the buckwheat varieties were subjected to molecular docking analysis to provide insight into their interactions with α-glucosidase. The contributions by individual phenolics to the observed variation was analysed by Pearson correlation coefficient analysis and principal component analysis. The present study provides a comprehensive comparison for the phenolic fractions of buckwheat varieties and identify the main contributors to antioxidant and α-glucosidase inhibitory activity.

Comprehensive Fractionation of Antioxidants and GC-MS and ESI-MS Fingerprints of Celastrus hindsii Leaves

Background: In this study, column chromatography was applied to separate active fractions from the ethyl acetate extract of Celastrus hindsii, a medicinal plant widely used in Southern China, Northern Vietnam, Myanmar, and Malaysia. Methods: Fourteen fractions from different dilutions of chloroform and methanol were separated by column chromatography and examined for biological activities. Results: It was found that a dilution of 50–70% methanol in chloroform yielded the highest total phenolics, flavonoids, and antioxidant activities (1,1-dipheny1-2-picrylhydrazyl (DPPH), 2,2-azinobis (3-ehtylbenzothiazoline-6-sulfonic acid), diammonium salt (ABTS) radical scavenging activity, and β-carotene bleaching method measured by lipid peroxidation inhibition). In addition, by gas chromatography-mass spectrometry (GC-MS) and electrospray ionization-mass spectrometry (ESI-MS) analyses, fifteen principal compounds from bioactive fractions belonging to fatty acids, amides, flavonoids, sterols, terpenes, and phenols were identified. Of these compounds, α-amyrin, β-amyrin, hydrazine carboxamide, hexadecanoic acid, fucosterol, (3β)-D:C-friedours-7-en-3-ol, rutin, and 2-hydroxy-1-ethyl ester accounted for maximal quantities, whilst concentrations of other constituents were <5%. Conclusions: It is suggested that these identified compounds may greatly contribute to the antioxidant capacity of C. hindsii as well as its potential pharmaceutical properties.

Isolation and Purification of Bioactive Compounds from the Stem Bark of Jatropha podagrica

This paper reports the successive isolation and purification of bioactive compounds from the stem bark of Jatropha podagrica, a widely known medicinal plant. The ethyl acetate extract of the stem bark exhibited the strongest antioxidant activity assessed by 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2′-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radical scavenging, and ferric reducing antioxidant power (FRAP) assays (IC₅₀ = 46.7, 66.0, and 492.6, respectively). By column chromatography (CC) with elution of hexane and ethyl acetate at 8:2, 7:3, and 6:4 ratios, the isolation of this active extract yielded five fractions (C1–C5). Chemical structures of the constituents included in C1–C5 were elucidated by gas chromatography-mass spectrometry (GC-MS), electrospray ionization-mass spectrometry (ESI-MS), and nuclear magnetic resonance (NMR) and resolved as methyl gallate (C1, C2, C3, C4), gallic acid (C1, C2), fraxetin (C2, C3, C4, C5), and tomentin (C3). Mixture C2 (IC₅₀ DPPH and ABTS = 2.5 µg/mL) and C3 (IC₅₀ FRAP = 381 µg/mL) showed the highest antioxidant properties. Among the isolated fractions, C4 was the most potential agent in growth inhibition of six bacterial strains including Staphylococcus aureus, Escherichia coli, Klebsiella pneumoniae, Listeria monocytogenes,Bacillus subtilis, and Proteus mirabilis (MIC = 5, 20, 30, 20, 25, and 20 mg/mL, respectively). All identified constituents exerted an inhibitory activity on the growth of Lactuca sativa, of which the mixture C3 performed the maximal inhibition on shoot (IC₅₀ = 49.4 µg/mL) and root (IC₅₀ = 47.1 µg/mL) growth. Findings of this study suggest that gallic acid, methyl gallate, fraxetin, and tomentin isolated from J. podagrica possessed antioxidant, antibacterial, and growth inhibitory potentials.

Antioxidant, α-Amylase and α-Glucosidase Inhibitory Activities and Potential Constituents of Canarium tramdenum Bark

The fruits of Canarium tramdenum are commonly used as foods and cooking ingredients in Vietnam, Laos, and the southeast region of China, whilst the leaves are traditionally used for treating diarrhea and rheumatism. This study was conducted to investigate the potential use of this plant bark as antioxidants, and α-amylase and α-glucosidase inhibitors. Five different extracts of C. tramdenum bark (TDB) consisting of the extract (TDBS) and factional extracts hexane (TDBH), ethyl acetate (TDBE), butanol (TDBB), and water (TDBW) were evaluated. The TDBS extract contained the highest amount of total phenolic (112.14 mg gallic acid equivalent per g dry weight), while the TDBB extract had the most effective antioxidant capacity compared to other extracts. Its IC₅₀ values were 12.33, 47.87, 33.25, and 103.74 µg/mL in 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2′-azino-bis (ABTS), reducing power (RP), and nitric oxide (NO) assays, respectively. Meanwhile, the lipid peroxidation inhibition of the four above extracts was proximate to that of butylated hydroxytoluene (BHT) as a standard antioxidant. The result of porcine pancreatic α-amylase inhibition showed that TDB extracts have promising effects which are in line with the commercial diabetic inhibitor acarbose. Interestingly, the inhibitory ability on α-glucosidase of all the extracts was higher than that of acarbose. Among the extracts, the TDBB extract expressed the strongest activity on the enzymatic reaction (IC₅₀ = 18.93 µg/mL) followed by the TDBW extract (IC₅₀ = 25.27 µg/mL), TDBS (IC₅₀ = 28.17 µg/mL), and TDBE extract (IC₅₀ = 141.37 µg/mL). The phytochemical constituents of the TDB extract were identified by gas chromatography–mass spectrometry (GC-MS). The principal constituents included nine phenolics, eight terpenoids, two steroids, and five compounds belonging to other chemical classes, which were the first reported in this plant. Among them, the presence of α- and β-amyrins were identified by GC-MS and appeared as the most dominant constituents in TDB extracts (1.52 mg/g). The results of this study revealed that C. tramdenum bark possessed rich phenolics and terpenoids, which might confer on reducing risks from diabetes. A high quantity of α- and β-amyrins highlighted the potentials of anti-inflammatory, anti-ulcer, anti-hyperlipidemic, anti-tumor, and hepatoprotective properties of C. tramdenum bark.

Phytochemical Analysis and Potential Biological Activities of Essential Oil from Rice Leaf

Although many investigations on phytochemicals in rice plant parts and root exudates have been conducted, information on the chemical profile of essential oil (EO) and potent biological activities has been limited. In this study, chemical compositions of rice leaf EO and in vitro biological activities were investigated. From 1.5 kg of fresh rice leaves, an amount of 20 mg EO was obtained by distillation and analyzed by gas chromatography-mass spectrometry (GC-MS), electrospray ionization (ESI), and atmospheric pressure chemical ionization (APCI) to reveal the presence of twelve volatile constituents, of which methyl ricinoleate (27.86%) was the principal compound, followed by palmitic acid (17.34%), and linolenic acid (11.16%), while 2-pentadecanone was the least (2.13%). Two phytoalexin momilactones A and B were first time identified in EO using ultra-performance liquid chromatography coupled with electrospray mass spectrometry (UPLC/ESI-MS) (9.80 and 4.93 ng/g fresh weight, respectively), which accounted for 7.35% and 3.70% of the EO, respectively. The assays of DPPH (IC50 = 73.1 µg/mL), ABTS (IC50 = 198.3 µg/mL), FRAP (IC50 = 700.8 µg/mL) and β-carotene oxidation (LPI = 79%) revealed that EO possessed an excellent antioxidant activity. The xanthine oxidase assay indicated that the anti-hyperuricemia potential was in a moderate level (IC50 = 526 µg/mL) as compared with the standard allopurinol. The EO exerted potent inhibition on growth of Raphanus sativus, Lactuca sativa, and two noxious weeds Echinochloa crus-galli, and Bidens pilosa, but in contrast, the growth of rice seedlings was promoted. Among the examined plants, the growth of the E. crus-galli root was the most inhibited, proposing that constituents found in EO may have potential for the control of the problematic paddy weed E. crus-galli. It was found that the EO of rice leaves contained rich phytochemicals, which were potent in antioxidants and gout treatment, as well as weed management. Findings of this study highlighted the potential value of rice leaves, which may provide extra benefits for rice farmers.

Total Polyphenol Content and Antioxidant Capacity of Rosehips of Some Rosa Species

Background: Rosehips, the fruits of Rosa species, are well known for their various health benefits like strengthening the immune system and treating digestive disorders. Antioxidant, anti-inflammatory, and cell regenerative effects are also among their health enhancing impacts. Rosehips are rich in compounds having antioxidant properties, like vitamin C, carotenoids, and phenolics. Methods: Total polyphenol content (Folin-Ciocalteu’s method), and in vitro total antioxidant capacity (ferric-reducing ability of plasma, FRAP) in rosehips of four Rosa species (R. canina, R. gallica, R. rugosa, R. spinosissima) were determined and compared. Ripe fruits were harvested at two locations. Water and ethanolic extracts of dried fruit flesh were analyzed. Results:R. spinosissima had the highest total phenolic content and antioxidant capacity, significantly higher than the other investigated Rosa species. Both parameters were reported in decreasing order for R. spinosissima > R. canina > R. rugosa > R. gallica. Ethanolic extracts of rosehips showed higher phenolic content and antioxidant activity than water extracts. Antioxidant properties were influenced by the growing site of Rosa species. Conclusions: This study indicates that R. spinosissima exhibited the greatest phenolic and antioxidant content, and therefore can be used as a reliable source of natural antioxidants, and serve as a suitable species for further plant breeding activities. Furthermore, investigations of various Rosa species for their antioxidant properties may draw more attention to their potential as functional foods.

Anti-Melanogenic Effect of Chestnut Spike Extract through Downregulation of Tyrosinase-Related Proteins and Activation of ERK 1/2

Melanin has been reported to be the key factor for skin homeostasis. Besides defining an important human phenotypic trait, melanin overproduction may cause various disorders such as vitiligo, Addison's disease, Cushing's syndrome, and melasma. In this study, we aimed to investigate the anti-melanogenic potential of dried spike extract of chestnut. The extract inhibited tyrosinase (TYR) activity in a dose-dependent manner. Cellular melanin content decreased markedly after treatment with the extract. The spike extract inhibited microphthalmia-associated transcription factor (MITF) expression and downregulated TYR, TYRP-1, and TYRP-2 protein expression by increasing the phosphorylation of extracellular signal-regulated kinase (ERK)1/2 signalling pathway in melan-a cells. In addition, treatment with U0126, a specific inhibitor of ERK, restored melanin content. Collectively, these results suggest that the chestnut spike extract attenuated melanogenesis by inhibiting MITF expression and downregulating TYR, TYRP-1, and TYRP-2 protein expressions via activation of ERK1/2 pathway.

Comparative Evaluation of Soluble and Insoluble-Bound Phenolics and Antioxidant Activity of Two Chinese Mistletoes

Mistletoes are used medicinally in order to treat various human illnesses. Few studies have reported on the phenolic content and antioxidant properties of Chinese mistletoes (CMs). In this work, the total phenolic content (TPC), total flavonoid content (TFC), and antioxidant activities of soluble and insoluble-bound phenolic extracts from CMs hosted by Camellia assamica (Mast.) Chang (CMC) and Pyrus, i, f. (CMP) were compared. Phenolic compounds in CMC and CMP were identified and quantified using high-performance liquid chromatography (HPLC). The results indicated that the TPC of soluble phenolic extracts was higher than insoluble-bound phenolic counterparts in both CMC and CMP. In addition, the TPC of soluble, insoluble-bound and total phenolic fractions (9.91 ± 0.23, 4.59 ± 0.27 and 14.50 ± 0.35 μmol ferulic acid equivalents per gram (FAE/g) dry sample) extracted from CMP were higher than those extracted from CMC. The soluble phenolic extracts in CMP showed higher antioxidant activities than those in CMC. Eighteen phenolic compounds from soluble and insoluble-bound phenolic extracts from the CMs were identified and quantified by HPLC. This study indicates that CMC and CMP, especially the latter, could be sources of antioxidants in human health care.

Weed Suppressing Potential and Isolation of Potent Plant Growth Inhibitors from Castanea crenata Sieb. et Zucc

This study isolated, determined, and quantified plant growth inhibitors in Japanese chestnut (Castanea crenata Sieb. et Zucc), a deciduous species native to Japan and Korea. In laboratory assays, C. crenata leaves showed strong inhibition on germination and seedling growth of Echinochloa crus-galli (barnyardgrass), Lactuca sativa (lettuce), and Raphanus sativus (radish). Laboratory and greenhouse trials showed that leaves of C. crenata appeared as a promising material to manage weeds, especially the dicot weeds. By GC-MS and HPLC analyses, gallic, protocatechuic, p-hydroxybenzoic, caffeic, ferulic, ellagic, and cinnamic acids were identified and quantified, of which ellagic acid was present in the highest quantity (2.36 mg/g dried leaves). By column chromatography and spectral data (¹H- and ¹³C-NMR, IR, and LC-MS) analysis, a compound identified as 2α,3β,7β,23-tetrahydroxyurs-12-ene-28-oic acid (1) was purified from the methanolic leaf extract of C. crenata (0.93 mg/g dried leaves). This constituent showed potent inhibition on growth of E. crus-galli, a problematic weed in agricultural practice. The inhibition of the compound 1 (IC₅₀ = 2.62 and 0.41 mM) was >5 fold greater than that of p-hydroxybenzoic acid (IC₅₀ = 15.33 and 2.11 mM) on shoot and root growth of E. crus-galli, respectively. Results suggest that the isolated the compound 1 has potential to develop natural herbicides to manage E. crus-galli. This study is the first to isolate and identify 2α,3β,7β,23-tetrahydroxyurs-12-ene-28-oic acid in a plant and report its plant growth inhibitory potential.