Altitudinal Variation of Antioxidant Components and Capability in Indocalamus latifolius (Keng) McClure Leaf

Quantitative analysis of six sesquiterpene glycosides from Dendrobium nobile Lindl. under different growth conditions by high-performance liquid chromatography coupled with triple quadrupole tandem mass spectrometry in MRM mode

INTRODUCTION

The sesquiterpene glycosides (SGs) from Dendrobium nobile Lindl. have immunomodulatory effects. However, there are no studies on the growth conditions affecting its contents and quantitative analysis methods.

OBJECTIVE

In the present study, a quantitative analysis method for six SGs from D. nobile was established. We explored which growth conditions could affect the contents of SGs, providing a basis for the cultivation and clinical application of D. nobile.

METHODS

Firstly, based on the optimization of mass spectrometry parameters and extraction conditions for six SGs in D. nobile, a method for the determination of the contents of six SGs was established using high-performance liquid chromatography coupled with triple quadrupole tandem mass spectrometry (HPLC-QqQ-MS/MS) in multiple reaction monitoring (MRM) mode. Then, the methodology of the established method was validated. Secondly, the established method was applied to determine the contents of six SGs from 78 samples of D. nobile grown under different growth conditions. Finally, chemometrics analysis was employed to analyze the results and select optimal growth conditions for D. nobile.

RESULTS

The results indicated significant variations in the contents of SGs from D. nobile grown under different growth conditions. The primary factors influencing SG contents included age, geographical origin, altitude, and epiphytic pattern.

CONCLUSION

Therefore, the established method for determining SG contents from D. nobile is stable. In particular, the SG contents were relatively high in samples of 3-year-old D. nobile grown at an altitude of approximately 500 m on Danxia rocks in Chishui, Guizhou.

Uncovering Metabolic Alterations in HCT-116 Colon Cancer Cells upon Exposure to Bamboo Leaf Extract Obtained from Guadua incana Londoño

Metabolic alterations are increasingly recognized as important aspects of colorectal cancer (CRC), offering potential avenues for identifying therapeutic targets. Previous studies have demonstrated the cytotoxic potential of bamboo leaf extract obtained from Guadua incana (BLEGI) against HCT-116 colon cancer cells. However, the altered metabolic pathways in these tumor cells remain unknown. Therefore, this study aimed to employ an untargeted metabolomic approach to reveal the metabolic alterations of the endometabolome and exometabolome of HCT-116 cells upon exposure to BLEGI treatment. First, a chemical characterization of the BLEGI was conducted through liquid chromatography coupled with mass spectrometry (LC-MS). Next, we assessed cell viability via MTT and morphological analysis using an immunofluorescence assay against colon cancer cells, and anti-inflammatory activity using an LPS-stimulated macrophage model. Subsequently, we employed LC-MS and proton nuclear magnetic resonance (1H-NMR) to investigate intra- and extracellular changes. Chemical characterization primarily revealed the presence of compounds with a flavone glycoside scaffold. Immunofluorescence analysis showed condensed chromatin and subsequent formation of apoptotic bodies, suggesting cell death by apoptosis. The results of the metabolomic analysis showed 98 differential metabolites, involved in glutathione, tricarboxylic acid cycle, and lipoic acid metabolism, among others. Additionally, BLEGI demonstrated significant nitric oxide (NO) inhibitory capacity in macrophage cells. This study enhances our understanding of BLEGI's possible mechanism of action and provides fresh insights into therapeutic targets for treating this disease.

Changes in Profiles of Classes and of Individual Polyphenols in Leaves of Spiraea chamaedryfolia and Spiraea media along an Altitudinal Gradient

Plants in high-altitude habitats are exposed to severe environmental stressors, including extreme temperatures and irradiation, which can have wide-ranging effects on changes of secondary-metabolite profiles in higher plants. Altitude-related variation of levels of polyphenols in organs of medicinal and food plant species has not yet been investigated sufficiently. This study was focused on variation in quantitative profiles of classes and of individual biologically active phenolic compounds in leaf extracts of resource species Spiraea chamaedryfolia and Spiraea media from the family Rosaceae in coenopopulations of the Altai Mountains, along an altitudinal gradient. High-performance liquid chromatography revealed 22 polyphenolic compounds in the extracts of S. media leaves, with the main polyphenolic compounds being flavonols. Sixteen compounds were found in S. chamaedryfolia leaf extracts, and the major ones were flavonols and a flavanone. Opposite responses to changes in the altitude-associated growth conditions were documented for levels of some individual polyphenolic compounds. With an increase in altitude, concentrations of chlorogenic acid and of flavanone in the extracts of S. chamaedryfolia leaves significantly increased, while concentrations of cinnamic acid, astragalin, and kaempferol diminished. A statistically significant positive correlation between the altitude of plant habitats and total levels of polyphenols and phenolcarboxylic acids was detected. In leaf extracts from S. media, an altitude increase was significantly positively correlated with astragalin, avicularin, and cinnamic acid levels and negatively correlated with hyperoside concentration.

Anti-Inflammatory and Antioxidant Effects of Leaves and Sheath from Bamboo (Phyllostacys edulis J. Houz)

Bamboo (Phyllostacys edulis J. Houz) has become an emerging forest resource of economic and ecological significance with health benefits. Since the beneficial effects of the non-edible parts of bamboo have not been thoroughly explored, we characterized in this study bamboo leaf (BL) and sheath (BS) extracts. The total phenol and flavonoid content (TPC and TFC), antioxidant activity (ABTS, DPPH, FRAP and β-carotene bleaching test) and anti-inflammatory properties were determined. Leaves exhibited a TPC value of 73.92 mg equivalent (eq) gallic acid/g fresh weight (FW) and a TFC value of 56.75 mg eq quercetin/g FW. Ultra-High-Performance Liquid Chromatography (UHPLC) coupled with photo diode array detector (PDA) analysis revealed evidence for the presence of protocatechuic acid, isoorientin, orientin and isovitexin in BL, whereas BS was rich in phenolic acids. Both samples demonstrated a significant ability to scavenge radicals against ABTS^·+, with an inhibitory concentration of 50% of 3.07 μg/mL for BL and 6.78 μg/mL for BS. At a concentration of 0.1 and 0.2 mg/mL, BS decreased reactive oxygen species production without hampering cell viability in HepG2 liver cells, while at the same concentrations, BL exhibited cytotoxicity in HepG2 cells. In addition, 0.1 and 0.2 mg/mL BS and BL reduced Interleukin-6 and Monocyte Chemoattractant Protein-1 production in human lipopolysaccharide-stimulated THP-1 macrophages, without affecting cell viability. These findings highlight the anti-inflammatory and antioxidant properties of BL and BS, corroborating their different potential applications in the nutraceutical, cosmetic and pharmaceutical industries.

Untargeted metabolomics approach and molecular networking analysis reveal changes in chemical composition under the influence of altitudinal variation in bamboo species

Bamboo species have traditionally been used as building material and potential source of bioactive substances, as they produce a wide variety of phenolic compounds, including flavonoids and cinnamic acid derivatives that are considered biologically active. However, the effects of growth conditions such as location, altitude, climate, and soil on the metabolome of these species still need to be fully understood. This study aimed to evaluate variations in chemical composition induced by altitudinal gradient (0-3000 m) by utilizing an untargeted metabolomics approach and mapping chemical space using molecular networking analysis. We analyzed 111 samples from 12 bamboo species collected from different altitudinal ranges using liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (LC-QTOF-MS). We used multivariate and univariate statistical analyses to identify the metabolites that showed significant differences in the altitude environments. Additionally, we used the Global Natural Products Social Molecular Networking (GNPS) web platform to perform chemical mapping by comparing the metabolome among the studied species and the reference spectra from its database. The results showed 89 differential metabolites between the altitudinal ranges investigated, wherein high altitude environments significantly increased the profile of flavonoids. While, low altitude environments significantly boosted the profile of cinnamic acid derivatives, particularly caffeoylquinic acids (CQAs). MolNetEnhancer networks confirmed the same differential molecular families already found, revealing metabolic diversity. Overall, this study provides the first report of variations induced by altitude in the chemical profile of bamboo species. The findings may possess fascinating active biological properties, thus offering an alternative use for bamboo.

Pseudotargeted metabolomics revealed the adaptive mechanism of Draba oreades Schrenk at high altitude

Strong ultraviolet radiation and low temperature environment on Gangshika Mountain, located in the eastern part of the Qilian Mountains in Qinghai Province, can force plants to produce some special secondary metabolites for resisting severe environmental stress. However, the adaptive mechanism of Draba oreades Schrenk at high altitude are still unclear. In the current study, Draba oreades Schrenk from the Gangshika Mountain at altitudes of 3800 m, 4000 m and 4200 m were collected for comprehensive metabolic evaluation using pseudotargeted metabolomics method. Through KEGG pathway enrichment analysis, we found that phenylpropanoid biosynthesis, phenylalanine, tyrosine and tryptophan biosynthesis and phenylalanine metabolism related to the biosynthesis of flavonoids were up-regulated in the high-altitude group, which may enhance the environmental adaptability to strong ultraviolet intensity and low temperature stress in high altitude areas. By TopFc20 distribution diagram, the content of flavonoids gradually increased with the elevation of altitude, mainly including apigenin, luteolin, quercetin, hesperidin, kaempferol and their derivatives. Based on the random forest model, 10 important metabolites were identified as potential biomarkers. L-phenylalanine, L-histidine, naringenin-7-O-Rutinoside-4'-O-glucoside and apigenin related to the flavonoids biosynthesis and plant disease resistance were increased with the elevation of altitude. This study provided important insights for the adaptive mechanism of Draba oreades Schrenk at high altitude by pseudotargeted metabolomics.

Altitudinal Variation of Metabolites, Mineral Elements and Antioxidant Activities of Rhodiola crenulata (Hook.f. & Thomson) H.Ohba

Rhodiolacrenulata (Hook.f. & Thomson) H.Ohba is an alpine medicinal plant that can survive in extreme high altitude environments. However, its changes to extreme high altitude are not yet clear. In this study, the response of Rhodiola crenulata to differences in altitude gradients was investigated through chemical, ICP-MS and metabolomic methods. A targeted study of Rhodiola crenulata growing at three vertical altitudes revealed that the contents of seven elements Ca, Sr, B, Mn, Ni, Cu, and Cd, the phenolic components, the ascorbic acid, the ascorbic acid/dehydroascorbate ratio, and the antioxidant capacity were positively correlated with altitude, while the opposite was true for total ascorbic acid content. Furthermore, 1165 metabolites were identified: flavonoids (200), gallic acids (30), phenylpropanoids (237), amino acids (100), free fatty acids and glycerides (56), nucleotides (60), as well as other metabolites (482). The differential metabolite and biomarker analyses suggested that, with an increasing altitude: (1) the shikimic acid-phenylalanine-phenylpropanoids-flavonoids pathway was enhanced, with phenylpropanoids upregulating biomarkers much more than flavonoids; phenylpropanes and phenylmethanes upregulated, and phenylethanes downregulated; the upregulation of quercetin was especially significant in flavonoids; upregulation of condensed tannins and downregulation of hydrolyzed tannins; upregulation of shikimic acids and amino acids including phenylalanine. (2) significant upregulation of free fatty acids and downregulation of glycerides; and (3) upregulation of adenosine phosphates. Our findings provide new insights on the responses of Rhodiola crenulata to extreme high altitude adversity.

Evaluation of Two Major Rhodiola Species and the Systemic Changing Characteristics of Metabolites of Rhodiola crenulata in Different Altitudes by Chemical Methods Combined with UPLC-QqQ-MS-Based Metabolomics

Rhodiola species have a long history of use in traditional medicine in Asian and European countries and have been considered to possess resistance to the challenges presented by extreme altitudes. However, the influence of different Rhodiola species on quality is unclear, as well as the influence of altitude on phytochemicals. In this study, the phenolic components and antioxidant abilities of two major Rhodiola species are compared, namely Rhodiolacrenulata and Rhodiola rosea, and the metabolomes of Rhodiolacrenulata from two representative elevations of 2907 and 5116 m are analyzed using a UPLC-QqQ-MS-based metabolomics approach. The results show that the phenolic components and antioxidant activities of Rhodiolacrenulata are higher than those of Rhodiola rosea, and that these effects in the two species are positively correlated with elevation. Here, 408 metabolites are identified, of which 178 differential metabolites (128 upregulated versus 50 downregulated) and 19 biomarkers are determined in Rhodiola crenulata. Further analysis of these differential metabolites showed a significant upregulation of flavonoids, featuring glucosides, the enhancement of the phenylpropanoid pathway, and the downregulation of hydrolyzed tannins in Rhodiola crenulata as elevation increased. Besides, the amino acids of differential metabolites were all upregulated as the altitude increased. Our results contribute to further exploring the Rhodiola species and providing new insights into the Rhodiola crenulata phytochemical response to elevation.

Blue honeysuckle (Lonicera caerulea subsp. edulis (Turcz. ex Herder) Hultén.) berries and changes in their ingredients across different locations

BACKGROUND

Interest in organic blue honeysuckle berries has increased in recent years. They are rich in various health-promoting compounds which are sensitive to different environmental factors and are modified during the growing season.

RESULTS

Honeysuckle berries from different locations differed significantly in their contents of primary and secondary metabolites. The location Ogulin, with the highest altitude and consequently high UV radiation, had the highest phenolic content (259.85 mg per 100 g). Additionally, Vukovski Vrh, with the lowest temperature, had the highest ascorbic acid content (36.83 mg per 100 g), while Šmartno pri Litiji and Višnja Gora, with the highest precipitation, had the highest organic acid contents (885.85 and 850.01 mg per 100 g respectively). A combination of stressful environmental conditions of temperature, water source and light intensity led to the highest saponin content in Višnja Gora (695 mg per 100 g), the highest tannin content in Dolnje Impolje (134 mg per 100 g) and the highest sugar content (2585.45 mg per 100 g) in Vučetinac.

CONCLUSION

The contents of bioactive substances were influenced by various environmental factors such as temperature, UV radiation, altitude, light intensity and fruit ripening stage. Different compounds respond distinctly to different environmental factors. © 2017 Society of Chemical Industry.

The higher the better? Differences in phenolics and cyanogenic glycosides in Sambucus nigra leaves, flowers and berries from different altitudes

BACKGROUND

Elderberry (Sambucus nigra L.) possesses high antioxidant activity and has been used to treat numerous medicinal disorders. In addition to their antioxidant properties, elderberry parts accumulate toxic cyanogenic glycosides (CGG). It has been proven that altitude influences the biosynthesis of many secondary metabolites. In the present study we investigated the change of phenolics and CGG in elder leaves, flowers, and berries induced by different altitudes and locations.

RESULTS

The data indicate that the accumulation of CGG and phenolics is affected by the altitude of the growing site. An increase of anthocyanin content was recorded in elder berries collected at higher elevations in both locations. Fruit collected at the foothills of location 2 contained 3343 µg g^-1 anthocyanins as opposed to fruit from the hilltop, which contained 7729 µg g^-1 . Elder berries contained the lowest levels of harmful CGG compared to other analysed plant parts. However, more cyanogenic glycosides were always present in plant parts collected at the hilltop. Accordingly, berries accumulated 0.11 µg g^-1 CGG at the foothills and 0.59 µg g^-1 CGG at the hilltop.

CONCLUSION

Elder berries and flowers collected at the foothill were characterised by the lowest levels of both beneficial (phenolics) and harmful compounds (CGG) and are suitable for moderate consumption. © 2016 Society of Chemical Industry.