Quantification of phenolic compounds in ripe and unripe bitter melons (Momordica charantia) and evaluation of the distribution of phenolic compounds in different parts of the fruit by UPLC–MS/MS

Momordica charantia Bioactive Components: Hypoglycemic and Hypolipidemic Benefits Through Gut Health Modulation

Momordica charantia (MC), a member of the Cucurbitaceae family, is well known for its pharmacological activities that exhibit hypoglycemic and hypolipidemic properties. These properties are largely because of its abundant bioactive compounds and phytochemicals. Over the years, numerous studies have confirmed the regulatory effects of MC extract on glycolipid metabolism. However, there is a lack of comprehensive reviews on newly discovered MC-related components, such as insulin receptor-binding protein-19, adMc1, and MC protein-30 and triterpenoids 3β,7β,25-trihydroxycucurbita-5,23(E)-dien-19-al, and the role of MC in gut microbiota and bitter taste receptors. This review offers an up-to-date overview of the recently reported chemical compositions of MC, including polysaccharides, saponins, polyphenolics, peptides, and their beneficial effects. It also provides the latest updates on the role of MC in the regulation of gut microbiota and bitter taste receptor signaling pathways. As a result, this review will serve as a theoretical basis for potential applications in the creation or modification of MC-based nutrient supplements.

Effect of conventional and novel techniques on extraction yield, chemical characterisation and biological activities of proteins from bitter gourd (Momordica charantia)

The study investigates the effect of conventional and novel extraction techniques on the protein extraction yield from bitter gourd seeds (Momordica charantia). Ultrasound assisted-extraction (UAE) treatment for 30 min at 4 °C using a 20 kHz ultrasound probe resulted in the highest extraction yield of crude proteins. After purification, 9.08 ± 0.23 g of protein with 82.69 ± 0.78% purity was obtained from 100 g of M. charantia seeds on a dry basis. Mass spectrometry identified proteins with reported antidiabetic activity. Antidiabetic assays showed significantly higher antidiabetic activity for the purified protein (81.10 ± 2.64%) compared to the crude protein (32.59 ± 2.76%). In vitro cytotoxicity analysis showed minimal cytotoxicity levels at concentrations <200 μg.mL-1. Overall, UAE was effective to obtain crude protein from M. charantia seeds and a subsequent purification step enhanced antidiabetic activity. However, further research is required to demonstrate in-vivo antidiabetic activity.

Evolutionary Analysis of the Melon (Cucumis melo L.) GH3 Gene Family and Identification of GH3 Genes Related to Fruit Growth and Development

The indole-3-acetic acid (IAA) auxin is an important endogenous hormone that plays a key role in the regulation of plant growth and development. In recent years, with the progression of auxin-related research, the function of the Gretchen Hagen 3 (GH3) gene has become a prominent research topic. However, studies focusing on the characteristics and functions of melon GH3 family genes are still lacking. This study presents a systematic identification of melon GH3 gene family members based on genomic data. The evolution of melon GH3 family genes was systematically analyzed by means of bioinformatics, and the expression patterns of the GH3 family genes in different melon tissues during different fruit developmental stages and with various levels of 1-naphthaleneacetic acid (NAA) induction were analyzed with transcriptomics and RT-qPCR. The melon genome contains 10 GH3 genes distributed across seven chromosomes, and most of these genes are expressed in the plasma membrane. According to evolutionary analysis and the number of GH3 family genes, these genes can be divided into three subgroups, and they have been conserved throughout the evolution of melon. The melon GH3 gene has a wide range of expression patterns across distinct tissue types, with expression generally being higher in flowers and fruit. Through promoter analysis, we found that most cis-acting elements contained light- and IAA-responsive elements. Based on the RNA-seq and RT-qPCR analyses, it can be speculated that CmGH3-5, CmGH3-6 and CmGH3-7 may be involved in the process of melon fruit development. In conclusion, our findings suggest that the GH3 gene family plays an important role in the development of melon fruit. This study provides an important theoretical basis for further research on the function of the GH3 gene family and the molecular mechanism underlying the development of melon fruit.

Untargeted Metabolomics Analysis of the Orchid Species Oncidium sotoanum Reveals the Presence of Rare Bioactive C-Diglycosylated Chrysin Derivatives

Plants are valuable sources of secondary metabolites with pharmaceutical properties, but only a small proportion of plant life has been actively exploited for medicinal purposes to date. Underexplored plant species are therefore likely to contain novel bioactive compounds. In this study, we investigated the content of secondary metabolites in the flowers, leaves and pseudobulbs of the orchid Oncidium sotoanum using an untargeted metabolomics approach. We observed the strong accumulation of C-diglycosylated chrysin derivatives, which are rarely found in nature. Further characterization revealed evidence of antioxidant activity (FRAP and DPPH assays) and potential activity against neurodegenerative disorders (MAO-B inhibition assay) depending on the specific molecular structure of the metabolites. Natural product bioprospecting in underexplored plant species based on untargeted metabolomics can therefore help to identify novel chemical structures with diverse pharmaceutical properties.

Chrysin: A polyedric flavone as a tool to explore new phytotherapeutic applications and drug design

In the field of pharmaceutical research, a branch that has become more and more interesting is phytochemistry. Among phytochemicals, flavonoids have been studied a lot over the past 30 years. This review summarizes the chemical characteristics, metabolism, applications, and toxicity of a particular flavonoid, chrysin, recorded in the last 10 years and supported by solid biological assays. Furthermore, this review highlights some derivatives of chrysin investigated to obtain more bioavailable molecules that maintain or improve chrysin's bioactivities, enclosing a chrysin patent section, as well.

Mining Candidate Genes Related to Heavy Metals in Mature Melon (Cucumis melo L.) Peel and Pulp Using WGCNA

The content of metal ions in fruits is inseparable from plant intake of trace elements and health effects in the human body. To understand metal ion content in the fruit and pericarp of melon (Cucumis melo L.) and the candidate genes responsible for controlling this process, we analyzed the metal ion content in distinct parts of melon fruit and pericarp and performed RNA-seq. The results showed that the content of metal ions in melon fruit tissue was significantly higher than that in the pericarp. Based on transcriptome expression profiling, we found that the fruit and pericarp contained elevated levels of DEGs. GO functional annotations included cell surface receptor signaling, signal transduction, organic substance metabolism, carbohydrate derivative binding, and hormone-mediated signaling pathways. KEGG pathways included pectate lyase, pentose and glucuronate interconversions, H⁺-transporting ATPase, oxidative phosphorylation, plant hormone signal transduction, and MAPK signaling pathways. We also analyzed the expression patterns of genes and transcription factors involved in hormone biosynthesis and signal transduction. Using weighted gene co-expression network analysis (WGCNA), a co-expression network was constructed to identify a specific module that was significantly correlated with the content of metal ions in melon, after which the gene expression in the module was measured. Connectivity and qRT–PCR identified five candidate melon genes, LOC103501427, LOC103501539, LOC103503694, LOC103504124, and LOC107990281, associated with metal ion content. This study provides a theoretical basis for further understanding the molecular mechanism of heavy metal ion content in melon fruit and peel and provides new genetic resources for the study of heavy metal ion content in plant tissues.

Effects of Novel Extraction Strategies on the Recovery of Phenolic Compounds and Associated Antioxidant Properties from Buckwheat Hull (Fagopyrum esculentum)

This study investigated the effects of novel extraction technologies, including ultrasound-assisted extraction (UAE), microwave-assisted extraction (MAE), pulsed electric field (PEF), high-pressure processing (HPP), enzyme-assisted extraction (EAE), and conventional extraction, on the recovery of phenolic compounds and associated antioxidant properties from buckwheat hull (Fagopyrum esculentum). Initially, twenty-four extraction strategies were investigated. Based on the results of the total phenolic content and antioxidant properties (DPPH and FRAP), twelve strategies (i.e., US (n = 2), PEF (n = 1), MW (n = 4), HPP (n = 4), and a control method) were selected for phenolic profiling carried out using liquid chromatography-mass spectrometry (LC-MS). Forty-one phenolic compounds were identified in the extracts, and a scanning electron microscope (SEM) analysis was also carried out on the treated residues to analyze the surface damage post-treatments. The results showed that samples treated with US (16.14 ± 0.06), PEF (9.94 ± 0.02), MW (12.63 ± 0.13), and HPP (21.76 ± 0.78) contained the highest total phenolic content (mg GAE/100 mg of DW). In the case of the antioxidant activities, the highest DPPH activities were obtained using HPP, MAE, and UAE, while no clear pattern was recorded in the case of FRAP activities. The highest DPPH and FRAP activities observed were 80.91 ± 0.22% and 23.98 ± 0.2 mg Trolox equivalents/100 mg, respectively. Additionally, the LC-MS results identified eleven different groups of phenolic compounds in buckwheat hull extracts, including anthocyanin, flavanol, flavanones, flavones, flavonol, phenolic acids, isoflavones, lignans, and quinones.

Chrysin: Perspectives on Contemporary Status and Future Possibilities as Pro-Health Agent

Chrysin belongs to the group of natural polyphenols. It can be found, among others, in honey, propolis and fruits and has a wide range of biological activities, including the prevention of oxidative stress, inflammation, neurodegeneration and carcinogenesis. Being a part of the human diet, chrysin is considered to be a promising compound to be used in the prevention of many diseases, including cancers, diabetes and neurodegenerative diseases such as Alzheimer's or Parkinson's. Nevertheless, due to the low solubility of chrysin in water and under physiological conditions, its bioavailability is low. For this reason, attempts at its functionalization have been undertaken, aiming to increase its absorption and thus augment its in vivo therapeutic efficacy. The aim of this review is to summarize the most recent research on chrysin, including its sources, metabolism, pro-health effects and the effects of its functionalization on biological activity and pharmacological efficacy, evaluated both in vitro and in vivo.

Ingestion of Okinawa Island Vegetables Increases IgA Levels and Prevents the Spread of Influenza RNA Viruses

Background: It has been hypothesized that flavonoid ingestion stimulates immunity, promotes health, and prevents human illness. The aim of this analysis was to evaluate the association of the levels of immunoglobulin A (IgA) with the prevention of influenza infections and with the polyphenols contained in Okinawan vegetables. Methods: IgA, immunoglobulin G (IgG), immunoglobulin M (IgM), and soluble interleukin-2 receptor (sIL-2R) levels were measured in 44 outpatients who regularly ingested vegetables grown on Okinawa Island (200–300 g/day for ≥ 300 days/year) with no history of influenza infection and in 73 patients who ingested the vegetables irregularly or not at all with a history of influenza infection. Results: The patients who regularly ate Okinawan vegetables had higher IgA, IgG, and IgM levels than those who did not. On the other hand, patients who did not consume Okinawan vegetables and had influenza had lower IgA, IgG, and IgM levels. In addition, the IgA and IgG levels showed significant positive correlations with the sIL-2R levels in both groups. Conclusions: It may be beneficial to eat vegetables abundant in polyphenols every day. Secretory IgA antibodies are an important part of the immune defense against viral diseases. People who ingest Okinawan vegetables have high IgA levels and might be more likely to develop immunity against influenza RNA viruses.

Antimicrobial Activity of Selected Medicinal Plants from a Sub-Saharan African Country against Bacterial Pathogens from Post-Operative Wound Infections

Background: Globally, the application of medicinal plants in the management of acute and chronic wounds can be considered a common occurrence in most traditional medicine practices. In view of this, many plants in the tropical and subtropical regions have been screened for their wound-healing activities. Consequently, plants having antimicrobial activity against multidrug-resistant (MD-R) pathogens can be considered great assets. Therefore, this study evaluated ethanolic and aqueous extracts of five medicinal plants (Psidium guajava, Myrianthus arboreus, Alchornea cordifolia, Momordica charantia, and Justicia flava) for their antimicrobial activities against MD-R bacterial pathogens isolated from post-operative wounds; Methods: This involved the aqueous and ethanolic extraction of the selected medicinal plants. Preliminary phytochemical constituents of the plants were examined. The agar well diffusion method was then used to determine the antibacterial activity of the leaves against reference strains (Escherichia coli ATCC 25922, Salmonella typhi ATCC 19430, Pseudomonas aeruginosa ATCC 27853 and Staphylococcus aureus ATCC 25923, and a Methicillin-Resistant Staphylococcus aureus strain) as well as the MDR clinical isolates (E. coli, P. aeruginosa, S. aureus and CoNS) from the wounds; Results: The preliminary phytochemical analysis of the leaves showed the presence of saponins, phenolics, and reducing sugars in almost all the plants tested. All plant extracts were observed to have some antimicrobial activity against at least one reference strain. For the clinical MDR isolates, A. cordifolia from this study showed highest inhibition to growth of all bacteria used. Activity of J. flava against S. aureus was highest as compared to that of E.coli and P. aeruginosa. Similar observation was made for M. arboreus, P. guajava and M. charantia where the highest activity was observed against S. aureus; Conclusion: This study has mainly shown that P. guajava, M. arboreus, A. cordifolia, M. charantia, and J. flava exhibits antimicrobial activities against MD-R bacterial pathogens isolated from post-operative wounds. Also, these plants has bioactive phytochemical compounds with potential medicinal values for the treatment of numerous infections. Therefore, these plants may be helpful in the management of acute and chronic wounds, especially in traditional medicine practices.

Pulp and peel of unripe stenospermocarpic mango (Mangifera indica L. cv Ataulfo) as an alternative source of starch, polyphenols and dietary fibre

As a result of climate change, the production of stenospermocarpic mangoes has increased dramatically. The stenospermocarpic mango, a fruit with reduced size and no seed, is considered to be a by-product that is both underutilised and wasted. Here, we studied the colour, chemical composition, polyphenol content, antioxidant capacity and starch in vitro digestibility of unripe stenospermocarpic mango flours (pulp and peel). The stenospermocarpic mango pulp flour had 11.7 g/100 g of dietary fibre with a balance of soluble and insoluble fractions; additionally, the total starch content of 41 g/100 g in its uncooked flour (resistant starch) can contribute to an increase in the indigestible carbohydrates. The mango peel flour had higher dietary fibre (40.5 g/100 g) and lower total starch content (21 g/100 g) compared with mango pulp flour. The mango pulp flour had higher phenolic compounds content (99.71 mg/g) and antioxidant capacity (248.5 mg/g, DPPH) compared with the peel flour (16.51 mg/g and 92.08 mg/g, DPPH), respectively. The rapidly digestible starch fraction was approximately 50%, with a balance in the content of slowly and resistant starch fractions in the mango pulp flour (approximately 20% per fraction). The flours of the pulp and peel of unripe stenospermocarpic mangoes can be used as alternative ingredients for preparing functional foods with high dietary fibre content and polyphenol compounds with antioxidant capacities.