Hydroxylated Tetramethoxyflavone Affects Intestinal Cell Permeability and Inhibits Cytochrome P450 Enzymes

Tetramethoxyflavones (TMFs) found in the Citrus genus have garnered considerable interest from food scientists and the health food industry because of their promising biological properties. Nonetheless, there are currently limited data available regarding the effectiveness and bioavailability of "hydroxylated TMFs", which are flavones known for their potential in disease prevention through dietary means. This study aims to provide insights into the chemical and biological properties of hydroxylated TMF and evaluates its effects on intestinal cell permeability and cytochrome P450 (CYP) inhibition. Liquid chromatography-mass spectrometry (LC-MS) and microsomes analyze the TMFs and hydroxylated TMFs, elucidating cell penetration and metabolic inhibition potential. 3H7-TMF shows the fastest (1-h) transport efficiency in intestinal cells. The Caco-2 cell model exhibits significant transport and absorption efficiency. Dissolved hydroxyl-TMF with hydrophilicity possibly permeates the gut. 3H7-TMF has higher transport efficiency (46%) 3H6-TMF (39%). IC50 values of TMFs (78-TMF, 57-TMF, 3H7-TMF, 3H6-TMF) against CYP enzymes (CYP1A2, CYP2D6, CYP2C9, CYP2C19, CYP3A4) range from 0.15 to 108 μM, indicating potent inhibition. Hydroxyl groups enhance TMF hydrophilicity and membrane permeability. TMFs display varied inhibitory effects due to hydroxyl and methoxy hindrance. This study underscores the strong CYP inhibitory capabilities in these TMFs, implying potential food-drug interactions if used in medicines or supplements. These findings can also help with food nutrition improvement and pharma food developments through innovative approaches for Citrus waste valorization.

Exploring Volatile Organic Compounds in Rhizomes and Leaves of Kaempferia parviflora Wall. Ex Baker Using HS-SPME and GC-TOF/MS Combined with Multivariate Analysis

Volatile organic compounds (VOCs) play an important role in the biological activities of the medicinal Zingiberaceae species. In commercial preparations of VOCs from Kaempferia parviflora rhizomes, its leaves are wasted as by-products. The foliage could be an alternative source to rhizome, but its VOCs composition has not been explored previously. In this study, the VOCs in the leaves and rhizomes of K. parviflora plants grown in a growth room and in the field were analyzed using the headspace solid-phase microextraction (HS-SPME) method coupled with gas chromatography and time-of-flight mass spectrometry (GC-TOF-MS). The results showed a total of 75 and 78 VOCs identified from the leaves and rhizomes, respectively, of plants grown in the growth room. In the field samples, 96 VOCs were detected from the leaves and 98 from the rhizomes. These numbers are higher compared to the previous reports, which can be attributed to the analytical techniques used. It was also observed that monoterpenes were dominant in leaves, whereas sesquiterpenes were more abundant in rhizomes. Principal component analysis (PCA) revealed significantly higher abundance and diversity of VOCs in plants grown in the field than in the growth room. A high level of similarity of identified VOCs between the two tissues was also observed, as they shared 68 and 94 VOCs in the growth room and field samples, respectively. The difference lies in the relative abundance of VOCs, as most of them are abundant in rhizomes. Overall, the current study showed that the leaves of K. parviflora, grown in any growth conditions, can be further utilized as an alternative source of VOCs for rhizomes.

The industrially important genus Kaempferia: An ethnopharmacological review

Kaempferia, a genus of the family Zingiberaceae, is widely distributed with more than 50 species which are mostly found throughout Southeast Asia. These plants have important ethnobotanical significance as many species are used in Ayurvedic and other traditional medicine preparations. This genus has received a lot of scholarly attention recently as a result of the numerous health advantages it possesses. In this review, we have compiled the scientific information regarding the relevance, distribution, industrial applications, phytochemistry, ethnopharmacology, tissue culture and conservation initiative of the Kaempferia genus along with the commercial realities and limitations of the research as well as missing industrial linkages followed by an exploration of some of the likely future promising clinical potential. The current review provides a richer and deeper understanding of Kaempferia, which can be applied in areas like phytopharmacology, molecular research, and industrial biology. The knowledge from this study can be further implemented for the establishment of new conservation strategies.

Black Ginger (Kaempferia parviflora) Extract Enhances Endurance Capacity by Improving Energy Metabolism and Substrate Utilization in Mice

Black ginger (Kaempferia parviflora) extract (KPE), extracted from KP, a member of the ginger family that grows in Thailand, has a good promotion effect on cellular energy metabolism and therefore has been used to enhance exercise performance and treatment of obesity in previous studies. However, the effect of single-dose administration of KPE on endurance capacity has not been thoroughly studied, and whether the positive effect of KPE on cellular energy metabolism can have a positive effect on exercise capacity in a single dose is unknown. In the present study, we used a mouse model to study the effects of acute KPE administration 1 h before exercise on endurance capacity and the underlying mechanisms. The purpose of our study was to determine whether a single administration of KPE could affect endurance performance in mice and whether the effect was produced through a pro-cellular energy metabolic pathway. We found that a single administration of KPE (62.5 mg/kg·bodyweight) can significantly prolong the exercise time to exhaustion. By measuring the mRNA expression of Hk2, Slc2a4 (Glut4), Mct1, Ldh, Cd36, Cpt1β, Cpt2, Lpl, Pnpla2 (Atgl), Aco, Acadm (Mcad), Hadh, Acacb (Acc2), Mlycd (Mcd), Pparg, Ppargc1a (Pgc-1α), Tfam, Gp, Gs, Pfkm, Pck1 (Pepck), G6pc (G6pase), Cs, and Pfkl in skeletal muscle and liver, we found that acute high-concentration KPE administration significantly changed the soleus muscle gene expression levels (p < 0.05) related to lipid, lactate, and glycogen metabolism and mitochondrial function. In gastrocnemius muscle and liver, glycogen metabolism-related gene expression is significantly changed by a single-dose administration of KPE. These results suggest that KPE has the potential to improve endurance capacity by enhancing energy metabolism and substrate utilization in muscles and liver.

Quantitative analysis of methoxyflavones discriminates between the two types of Kaempferia parviflora

INTRODUCTION

Kaempferia parviflora or black ginger is abundantly cultivated because its rhizomes contain methoxyflavones that have many pharmacological properties. K. parviflora can be divided into two types, based on morphological characteristics, but differences in their chemical compositions have never been explored.

OBJECTIVES

This research aims to find chemical markers that can be used to differentiate between the two types of K. parviflora, the red-leaf and green-leaf types, by quantifying the amounts of methoxyflavones.

MATERIAL AND METHODS

K. parviflora samples were collected from 39 locations in Thailand. Their genetic diversity was assessed by a genotyping-by-sequencing (GBS) technique to construct the population structure. Their chemical compositions were analyzed by high performance liquid chromatography-photodiode array detection to determine the methoxyflavone contents.

RESULTS

The population structure based on >3,000 single nucleotide polymorphism (SNP) markers showed that the samples can be divided into two groups, which were consistent with the classification by leaf margin color (red-leaf and green-leaf types). HPLC analysis revealed 3,5,7,3',4'-pentamethoxyflavone (PMF), 5,7-dimethoxyflavone (DMF), 5,7,4'-trimethoxyflavone (TMF), 3,5,7-trimethoxyflavone and 3,5,7,4'-tetramethoxyflavone as major methoxyflavones that can be used as chemical markers. The red-leaf type showed higher amounts of PMF, TMF and 3,5,7,4'-tetramethoxyflavone than the green-leaf type, while the green-leaf type showed higher amounts of DMF and 3,5,7-trimethoxyflavone than the red-leaf type.

CONCLUSION

These results provide another approach to discriminate the two types of K. parviflora using chemical profiles alongside genetic and morphological analyses. Therefore, a specific type of K. parviflora can be selected over the other based on preferences for a certain methoxyflavone.

Analysis of Lipophilic Antioxidants in the Leaves of Kaempferia parviflora Wall. Ex Baker Using LC-MRM-MS and GC-FID/MS

Lipophilic metabolites such as carotenoids, fatty acids, vitamin K1, phytosterols, and tocopherols are important antioxidants that are used in the cosmetics, foods, and nutraceutical industries. Recently, there has been a growing demand for the use of byproducts (wastes) as a potential source of industrially important compounds. The leaves of Kaempferia parviflora (black ginger) (KP-BG) are major byproducts of KP-BG cultivation and have been reported to contain several bioactive metabolites; however, the composition of lipophilic metabolites in KP-BG leaves has not been examined. In this study, the lipophilic antioxidant profile was analyzed in the leaves of KP-BG plants grown in vitro and ex vitro. Lipophilic compounds, namely carotenoids (80.40-93.84 µg/g fresh weight (FW)), tocopherols (42.23-46.22 µg/g FW), phytosterols (37.69-44.40 µg/g FW), and vitamin K1 (7.25-7.31 µg/g FW), were quantified using LC-MRM-MS. The fatty acid profile of the KP-BG leaves was identified using GC-FID/MS. The content of individual lipophilic compounds varied among the KP-BG leaves. Ex vitro KP-BG leaves had high levels of lutein (44.38 µg/g FW), α-carotene (14.79 µg/g FW), neoxanthin (12.30 µg/g FW), β-carotene (11.33 µg/g FW), violaxanthin (11.03 µg/g FW), α-tocopherol (39.70 µg/g FW), α-linolenic acid (43.12%), palmitic acid (23.78%), oleic acid (12.28%), palmitoleic acid (3.64%), total carotenoids (93.84 µg/g FW), and tocopherols (46.22 µg/g FW) compared with in vitro KP-BG leaves. These results indicate that ex-vitro-grown KP-BG leaves could be used as a valuable natural source for extracting important lipophilic antioxidants.

Establishment of a Rapid Micropropagation System for Kaempferia parviflora Wall. Ex Baker: Phytochemical Analysis of Leaf Extracts and Evaluation of Biological Activities

This study aimed to establish a rapid in vitro plant regeneration method from rhizome buds of Kaempferia parviflora to obtain the valuable secondary metabolites with antioxidant and enzyme inhibition properties. The disinfection effect of silver oxide nanoparticles (AgO NPs) on rhizome and effects of plant growth regulators on shoot multiplication and subsequent rooting were investigated. Surface sterilization of rhizome buds with sodium hypochlorite was insufficient to control contamination. However, immersing rhizome buds in 100 mg L⁻¹ AgO NPs for 60 min eliminated contamination without affecting the survival of explants. The number of shoots (12.2) produced per rhizome bud was higher in Murashige and Skoog (MS) medium containing 8 µM of 6-Benzyladenine (6-BA) and 0.5 µM of Thidiazuron (TDZ) than other treatments. The highest number of roots (24), with a mean root length of 7.8 cm and the maximum shoot length (9.8 cm), were obtained on medium MS with 2 µM of Indole-3-butyric acid (IBA). A survival rate of 98% was attained when plantlets of K. parviflora were acclimatized in a growth room. Liquid chromatography with tandem mass spectrometry (LC-MS/MS) was used to determine the chemical profile of K. parviflora leaf extracts. Results showed that several biologically active flavonoids reported in rhizomes were also present in leaf tissues of both in vitro cultured and ex vitro (greenhouse-grown) plantlets of K. parviflora. We found 40 and 36 compounds in in vitro cultured and ex vitro grown leaf samples, respectively. Greenhouse leaves exhibited more potent antioxidant activities than leaves from in vitro cultures. A higher acetylcholinesterase inhibitory ability was obtained for greenhouse leaves (1.07 mg/mL). However, leaves from in vitro cultures exhibited stronger butyrylcholinesterase inhibitory abilities. These results suggest that leaves of K. parviflora, as major byproducts of black ginger cultivation, could be used as valuable alternative sources for extracting bioactive compounds.

Preventive effect of insect tea primary leaf (Malus sieboldii (Regal) Rehd.) extract on D-galactose-induced oxidative damage in mice

Insect tea is consumed as a health beverage in China. The insect tea primary leaf (ITPL) is rich in bioactive substances, which are also used as traditional Chinese medicine. This study investigated the role of ITPL in reducing the oxidative response induced by D-galactose in mice. Mice were intraperitoneally injected with D-galactose to induce oxidative damage. The effect of ITPL was tested by pathological observation, serum detection with kits, quantitative polymerase chain reaction, and Western blot. The experimental results show that ITPL increased the thymus, brain, heart, liver, spleen, and kidney indices of oxidized mice. ITPL increased superoxide dismutase, glutathione peroxidase, and glutathione levels and reduced nitric oxide and malondialdehyde levels in the serum, liver, and spleen in oxidative damaged mice. The pathological observations show that ITPL reduced the oxidative damage of the liver and spleen in mice induced with D-galactose. Simultaneously, ITPL upregulated mRNA expression of neuronal nitric oxide synthase, endothelial nitric oxide synthase, cuprozinc-superoxide dismutase, manganese superoxide dismutase, catalase, heme oxygenase-1, nuclear factor-erythroid 2 related factor 2, γ-glutamylcysteine synthetase, and NAD(P)H dehydrogenase [quinone] 1, and downregulated the expression of inducible nitric oxide synthase in the liver and spleen of oxidized mice. ITPL had beneficial preventive effects on the oxidative damage caused by D-galactose in mice and was more effective as an antioxidant than vitamin C. The component analysis test by high-performance liquid chromatography indicated that ITPL contained the following seven compounds: neochlorogenic acid, cryptochlorogenic acid, rutin, kaempferin, isochlorogenic acid B, isochlorogenic acid A, and hesperidin. ITPL is a plant with excellent antioxidant activities derived from its bioactive substances.

Glucose Tolerance-Improving Activity of Helichrysoside in Mice and Its Structural Requirements for Promoting Glucose and Lipid Metabolism

An acylated flavonol glycoside, helichrysoside, at a dose of 10 mg/kg/day per os for 14 days, improved the glucose tolerance in mice without affecting the food intake, visceral fat weight, liver weight, and other plasma parameters. In this study, using hepatoblastoma-derived HepG2 cells, helichrysoside, trans-tiliroside, and kaempferol 3-O-β-d-glucopyranoside enhanced glucose consumption from the medium, but their aglycones and p-coumaric acid did not show this activity. In addition, several acylated flavonol glycosides were synthesized to clarify the structural requirements for lipid metabolism using HepG2 cells. The results showed that helichrysoside and related analogs significantly inhibited triglyceride (TG) accumulation in these cells. The inhibition by helichrysoside was more potent than that by other acylated flavonol glycosides, related flavonol glycosides, and organic acids. As for the TG metabolism-promoting activity in high glucose-pretreated HepG2 cells, helichrysoside, related analogs, and their aglycones were found to significantly reduce the TG contents in HepG2 cells. However, the desacyl flavonol glycosides and organic acids derived from the acyl groups did not exhibit an inhibitory impact on the TG contents in HepG2 cells. These results suggest that the existence of the acyl moiety at the 6′′ position in the D-glucopyranosyl part is essential for glucose and lipid metabolism-promoting activities.

Hepatoprotective Limonoids from Andiroba (Carapa guianensis)

Three gedunin-type limonoids, gedunin (1), 6α-acetoxygedunin (2), and 7-deacetoxy-7-oxogedunin (3), which were isolated from the seed and flower oils of andiroba (Carapa guianensis Aublet, Meliaceae), exhibited hepatoprotective effects at doses of 25 mg/kg, p.o. against d-galactosamine (d-GalN)/lipopolysaccharide (LPS)-induced liver injury in mice. To characterize the mechanisms of action of 1-3 and clarify the structural requirements for their hepatoprotective effects, 17 related limonoids (1-17) isolated from the seed and/or flower oils of C. guianensis were examined in in vitro studies assessing their effects on (i) d-GalN-induced cytotoxicity in primary cultured mouse hepatocytes, (ii) LPS-induced nitric oxide (NO) production in mouse peritoneal macrophages, and (iii) tumor necrosis factor-α (TNF-α)-induced cytotoxicity in L929 cells. The mechanisms of action of 1-3 are likely to involve the inhibition of LPS-induced macrophage activation and reduced sensitivity of hepatocytes to TNF-α; however, these compounds did not decrease the cytotoxicity caused by d-GalN. In addition, the structural requirements of limonoids (1-17) for inhibition of LPS-induced NO production in mouse peritoneal macrophages and TNF-α-induced cytotoxicity in L929 cells were evaluated.

Enhancement of energy production by black ginger extract containing polymethoxy flavonoids in myocytes through improving glucose, lactic acid and lipid metabolism

Enhancement of muscular energy production is thought to improve locomotive functions and prevent metabolic syndromes including diabetes and lipidemia. Black ginger (Kaempferia parviflora) has been cultivated for traditional medicine in Thailand. Recent studies have shown that black ginger extract (KPE) activated brown adipocytes and lipolysis in white adipose tissue, which may cure obesity-related dysfunction of lipid metabolism. However, the effect of KPE on glucose and lipid utilization in muscle cells has not been examined yet. Hence, we evaluated the effect of KPE and its constituents on energy metabolism in pre-differentiated (p) and differentiated (d) C2C12 myoblasts. KPE (0.1-10 μg/ml) was added to pC2C12 cells in the differentiation process for a week or used to treat dC2C12 cells for 24 h. After culturing, parameters of glucose and lipid metabolism and mitochondrial biogenesis were assessed. In terms of the results, KPE enhanced the uptake of 2-deoxyglucose and lactic acid as well as the mRNA expression of glucose transporter (GLUT) 4 and monocarboxylate transporter (MCT) 1 in both types of cells. The expression of peroxisome proliferator-activated receptor γ coactivator (PGC)-1α was enhanced in pC2C12 cells. In addition, KPE enhanced the production of ATP and mitochondrial biogenesis. Polymethoxy flavonoids in KPE including 5-hydroxy-7-methoxyflavone, 5-hydroxy-3,7,4'-trimethoxyflavone and 5,7-dimethoxyflavone enhanced the expression of GLUT4 and PGC-1α. Moreover, KPE and 5,7-dimethoxyflavone enhanced the phosphorylation of 5'AMP-activated protein kinase (AMPK). In conclusion, KPE and its polymethoxy flavonoids were found to enhance energy metabolism in myocytes. KPE may improve the dysfunction of muscle metabolism that leads to metabolic syndrome and locomotive dysfunction.

Suppression of adipocyte hypertrophy by polymethoxyflavonoids isolated from Kaempferia parviflora

We previously demonstrated that ethyl acetate extracts of Kaempferia parviflora Wall. Ex Baker (KPE) improve insulin resistance in TSOD mice and showed that its components induce differentiation and adipogenesis in 3T3-L1 preadipocytes. The present study was undertaken to examine whether KPE and its isolated twelve components suppress further lipid accumulation in 3T3-L1 mature adipocytes. KPE reduced intracellular triglycerides in mature adipocytes, as did two of its components, 3,5,7,3',4'-pentamethoxyflavone and 5,7,4'-trimethoxyflavone. Shrinkage of lipid droplets in mature adipocytes was observed, and mRNA expression levels of adipose tissue triglyceride lipase (ATGL) and hormone-sensitive lipase (HSL) were up-regulated by these two polymethoxyflavonoids (PMFs). Furthermore, the protein expression level of ATGL and the release level of glycerol into the cell culture medium increased. In contrast, the peroxisome proliferator-activated receptor γ (PPARγ) agonist, troglitazone, did not decrease intracellular triglycerides in mature adipocytes, and the mRNA expression level of PPARγ was not up-regulated in mature adipocytes treated with the two active PMFs. Therefore, suppression of lipid accumulation in mature adipocytes is unlikely to be enhanced by transcriptional activation of PPARγ. These results suggest that KPE and its active components enhance lipolysis in mature adipocytes by activation of ATGL and HSL independent of PPARγ transcription, thus preventing adipocyte hypertrophy. On the other hand, the full hydroxylated flavonoid quercetin did not show the suppressive effects of lipid accumulation in mature adipocyte in the same conditions. Consequently, methoxy groups in the flavones are important for the activity.