Nutritional composition and antioxidant properties of the sim fruit (Rhodomyrtus tomentosa)

Analysis of the Rhodomyrtus tomentosa mitochondrial genome: Insights into repeat-mediated recombination and intra-cellular DNA transfer

Plant mitochondrial genomes participate in encoding proteins crucial to the major producers of ATP in the cell and replication and heredity of their own DNA. The sequences and structure of the plant mitochondrial genomes profoundly impact these fundamental processes, and studies of plant mitochondrial genomes are needed. We reported the complete sequences of the Rhodomyrtus tomentosa mitochondrial genome here, totaling 400,482 bp. Nanopore ONT reads and PCR amplification provided evidence for recombination mediated by the eight repeat pairs for the R. tomentosa mitochondrial genome. Thirty-eight genes were identified in the R. tomentosa mitochondrial genome. Comparative analyses of the mitochondrial genome and plastome and PCR amplification suggest that five fragments of mitochondrial plastid DNA were unfunctional sequences resulting from intracellular gene transfer. Phylogenetic analysis based on each and all of the 27 mitochondrial protein-coding genes of nine Myrtales species revealed that R. tomentosa always clustered with other species of Myrtaceae. This study uncovered the enormous complexity of the R. tomentosa mitochondrial genome, the active repeat-mediated recombinations, the presence of mitochondrial plastid DNAs, and the topological incongruence of Myrtales among the single-gene trees.

Rhodomyrtus tomentosa (Aiton) Hassk. (haramonting) protects against allethrin-exposed pulmo damage in rats: mechanistic interleukins

Inhaling Allethrin (C19H26O3) may induce oxidative stress in lung cells by causing the formation of free radi-cals. Interleukins (IL) are a group of secreted cytokines or proteins and signaling molecules initially produced as an immune response by leukocytes. Rhodomyrtus tomentosa (Aiton) Hassk. (haramonting) contains antioxidants that may prevent lung damage induced by allethrin-containing electric mosquito repellents. In this study, six groups of rats were exposed to allethrin via an electric mosquito repellent, including positive, negative, and comparison control groups and three groups were administered Rhodomyrtus tomentosa (Aiton) Hassk at 100 mg/kg BW, 200 mg/kg BW, and 300 mg/kg BW. After 30 days, the pulmonary tissue and the blood were taken for immunohisto-chemical and ELISA analysis. The accumulation of inflammatory cells causes the thickening of the alveolar wall structures. Injuries were more prevalent in the A+ group than in the other groups. The connection between the alveoli and blood capillaries, which can interfere with alveolar gas exchange, is not regulated, and the lu-minal morphology is aberrant, causing damage to the alveolar epithelial cells. Exposure to electric mosquito coils containing allethrin can increase the expression of interleukin-1, interleukin-8, interleukin-9, and interleu-kin-18 in blood serum and tissues while decreasing the expression of interleukin-6 and interleukin-10. Like the Vitamin C group, Rhodomyrtus tomentosa can increase alveolar histological alterations by decreasing the ex-pression of IL-1β, IL-8, IL-9, and IL-18 while increasing IL-6 and IL-10. So that this plant can be developed in the future as a drug to prevent lung harm from exposure.

Complete Genome of Rose Myrtle, Rhodomyrtus tomentosa, and Its Population Genetics in Thai Peninsula

Several parts of rose myrtle, Rhodomyrtus tomentosa, exhibited profound antibacterial and anti-inflammatory activities, suggesting its potential in healthcare and cosmetics applications. During the past few years, the demand for biologically active compounds in the industrial sectors increased. Therefore, gathering comprehensive information on all aspects of this plant species is essential. Here, the genome sequencing using short and long reads was used to understand the genome biology of R. tomentosa. Inter-simple sequence repeats (ISSR) and simple sequence repeats (SSR) markers, and geometric morphometrics of the leaves of R. tomentosa collected across Thai Peninsula, were determined for population differentiation analysis. The genome size of R. tomentosa was 442 Mb, and the divergence time between R. tomentosa and Rhodamnia argentea, the white myrtle of eastern Australia, was around 15 million years. No population structure was observed between R. tomentosa on the eastern and western sides of the Thai Peninsula using the ISSR and SSR markers. However, significant differences in leaf size and shape of R. tomentosa were observed in all locations.

Gap-free genome assembly and comparative analysis reveal the evolution and anthocyanin accumulation mechanism of Rhodomyrtus tomentosa

Rhodomyrtus tomentosa is an important fleshy-fruited tree and a well-known medicinal plant of the Myrtaceae family that is widely cultivated in tropical and subtropical areas of the world. However, studies on the evolution and genomic breeding of R. tomentosa were hindered by the lack of a reference genome. Here, we presented a chromosome-level gap-free T2T genome assembly of R. tomentosa using PacBio and ONT long read sequencing. We assembled the genome with size of 470.35 Mb and contig N50 of ~43.80 Mb with 11 pseudochromosomes. A total of 33 382 genes and 239.31 Mb of repetitive sequences were annotated in this genome. Phylogenetic analysis elucidated the independent evolution of R. tomentosa starting from 14.37MYA and shared a recent WGD event with other Myrtaceae species. We identified four major compounds of anthocyanins and their synthetic pathways in R. tomentosa. Comparative genomic and gene expression analysis suggested the coloring and high anthocyanin accumulation in R. tomentosa tends to be determined by the activation of anthocyanin synthesis pathway. The positive selection and up-regulation of MYB transcription factors were the implicit factors in this process. The copy number increase of downstream anthocyanin transport-related OMT and GST gene were also detected in R. tomentosa. Expression analysis and pathway identification enriched the importance of starch degradation, response to stimuli, effect of hormones, and cell wall metabolism during the fleshy fruit development in Myrtaceae. Our genome assembly provided a foundation for investigating the origins and differentiation of Myrtaceae species and accelerated the genetic improvement of R. tomentosa.

Rhodomyrtus tomentosa Fruits in Two Ripening Stages: Chemical Compositions, Antioxidant Capacity and Digestive Enzymes Inhibitory Activity

Rhodomyrtus tomentosa fruit (RTF) has been known as a food source with multiple health-care components. In this work, nutrition characteristics, free and bound phenolic profiles, antioxidant properties in vitro and digestive enzymes inhibitory activities of un-fully mature RTF (UM-RTF) and fully mature RTF (FM-RTF) were evaluated for the first time. Results verified that high levels of energy, ascorbic acid, organic acids and total phenolics were observed in FM-RTF. Moreover, FM-RTF had significant higher total phenolic content (TPC), but significantly lower total flavonoid content (TFC) than UM-RTF. In addition, twenty phenolic compounds in RTF were identified by high performance liquid chromatography-electrospray ionization-quadrupole time-of-flight tandem mass spectrometry (HPLC-ESI-qTOF-MS/MS) method. Quantitative analysis results indicated that gallic acid, ellagic acid and astragalin were the predominant free phenolics, while gallic acid and syringetin-3-O-glucoside were dominant in bound phenolic fractions. In contrast, higher contents of phenolics were observed in FM-RTF. The results also confirmed that FM-RTF exhibited higher antioxidant activities and digestive enzymes inhibitory activities than UM-RTF. Strong inhibitory ability on α-glucosidase was found in RTF, while bound phenolics showed a stronger α-amylase inhibitory effect than free phenolics. Moreover, the interaction between the main phenolic compounds and α-glucosidase/α-amylase was preliminary explored by molecular docking analysis. The results provided valuable data about the chemical compositions and biological potential of R. tomentosa fruits in both maturation stages studied.

Pinus thunbergii bark extract rich in flavonoids promotes hair growth in dorsal skin by regulating inflammatory cytokines and increasing growth factors in mice

Korean maritime pine bark (Pinus thunbergii) has been used as an alternative medicine due to its beneficial properties, including anti-inflammatory effects. To date, the anti-inflammatory and hair growth-promoting effects of Pinus densiflora bark extract have remained elusive. Therefore, in the present study, Pinus thunbergii bark was extracted with pure water (100°C) and the extract was examined to determine its polyphenol and flavonoid content. C57BL/6 mice were used to assess the effects of the extract to promote hair growth. The extract (1, 2 and 4%) was topically applied onto shaved dorsal skin and hair growth was observed for 17 days. A significant increase in hair growth was observed with 2 and 4% extract. Based on this finding, the optimal dose of the extract for effective hair growth promotion was determined to be 2%. The mechanisms of hair growth promotion were investigated via immunohistochemical analysis of changes in inflammatory cytokines and growth factors in the hair follicles following treatment with 2% extract. The treatment reduced the levels of TNF-α and IL-1β, which are pro-inflammatory cytokines, while it enhanced the levels of IL-4 and IL-13, which are anti-inflammatory cytokines, in the hair follicles. In addition, elevated insulin-like growth factor I and vascular epidermal growth factor were detected in hair follicles following treatment. Based on these findings, it was suggested that the extract of Pinus thunbergii bark may be utilized for hair loss prevention and/or hair growth promotion.

Exploring the potential mechanism of Rhodomyrtus tomentosa (Ait.) Hassk fruit phenolic rich extract on ameliorating nonalcoholic fatty liver disease by integration of transcriptomics and metabolomics profiling

Nonalcoholic fatty liver disease (NAFLD), as the commonest form of chronic liver disease, is accompanied by liver oxidative stress and inflammatory responses. Rhodomyrtus tomentosa (Ait.) Hassk fruit phenolic rich extract (RTE) possesses multiple pharmacological effects in management of chronic diseases. In this study, the liver-protective effect of RTE on mice with high-fat-diet (HFD)-induced NAFLD was investigated for the first time, and the underlying molecular mechanism was explored via integration of transcriptomics and metabolomics. The results showed that RTE mitigated liver damage, which was evidenced by declined inflammatory cell infiltration in liver, decreased liver function markers, oxidative stress indexes, lipid profile levels and inflammatory cytokines levels. The differential metabolites by metabonomics illustrated supplementation of RTE affected metabolomics pathways including tryptophan metabolism, alanine, aspartate and glutamate metabolism, D-glutamine and D-glutamate metabolism, cysteine and methionine metabolism, arginine and proline metabolism, which are all involved in oxidative stress and inflammation. Furthermore, the five differential expression genes (DEGs) through liver transcriptomics were screened and recognized, namely Tnfrsf21, Ifit1, Inhbb, Mapk15 and Gadd45g, which revealed that HFD induced Cytokine-cytokine receptor interaction pathway, NF-κB signaling pathway NOD-like receptor pathway, TNF signaling pathway. Integrated analysis of transcriptomics and metabolomics confirmed the supplementation of RTE had significantly regulatory effects on the metabolic pathways involved in inflammatory responses. Additionally, RT-PCR and western blot authenticated RTE intervention regulated the mRNA levels of liver genes involved in inflammation response and inhibited the liver endotoxin-TLR4-NF-κB pathway triggered by HFD, thus alleviating NAFLD. Our findings strongly support the possibility that RTE can be regarded as a potential therapeutic method for obesity-associated NAFLD.

Effect of supplementation of Rhodomyrtus tomentosa fruit juice in preventing hypercholesterolemia and atherosclerosis development in rats fed with high fat high cholesterol diet

Cardiovascular diseases (CVDs) are the leading cause of death worldwide. Nutraceuticals, mainly based on natural products, have been proven to control the risk factors of CVDs effectively. Rhodomyrtus tomentosa is an underutilized fruit that is rich in phenolic compounds and has antioxidant activities. Scientific investigation was needed to verify the pharmacological properties of R. tomentosa fruit juice in Sprague-Dawley rats fed with high fat high cholesterol (HFHC) as antihypercholesterolemic and antiatherosclerotic agents. The experiments were carried out using male albino rats fed with HFHC diet for 75 days and at the same time orally supplemented with R. tomentosa fruit juice (RTFJ) in doses of 0.5, 1, and 2 g/kg body weight (BW) daily for 75 days. Simvastatin was used as a positive control. At the end of the experiment, the blood was collected, and the serum was assayed for total triglycerides (TG), total cholesterol (TC), low-density lipoprotein (LDL-C), and high-density lipoprotein (HDL-C). The histopathology of coronary and aorta arteries was observed under the light microscope. The results demonstrated that the supplementation of RTFJ significantly prevented the increase of total triglycerides, total cholesterol, low-density lipoprotein, and the decrease of high-density lipoprotein in serum. Supplementation of RTFJ also prevents atherosclerosis development by preventing the thickening of the blood vessel wall, deposition of lipid formation, and foam cells in the tunica intima of the aorta and coronary arteries. These findings suggested that supplementation of R. tomentosa fruit juice prevents hypercholesterolemia and atherosclerosis.

Potential of karamunting (Rhodomyrtus tomentosa) fraction against kidney damage in diabetic rats

Introduction: Karamunting (Rhodomyrtus tomentosa) is Indonesian native plant that contains high anti-oxidant compounds with the potential to suppress oxidative stress activity in cells. This study is the first research to specifically explore the role of the karamunting fraction in protecting kidney damage due to the formation of AGEs in the renal glomerulus in diabetes mellitus.

Objective: This study aims to assess the impact of karamunting on blood glucose profile, HbA1c, insulin profile and kidney condition (AGEs expression, TNF-α and kidney histology) in diabetic rats.

Methods: The karamunting extraction process was carried out by maceration with ethanol. Induction of diabetes mellitus was carried out using streptozotocin. Thirty male rats (Rattus norvegicus), Wistar strain weighing between 200–250 grams were the subject in this study. HbA1c, insulin, TNF-α, AGEs levels were evaluated in the kidney tissue. Histological assessment of the kidney was carried out.

Results: Karamunting can improve blood glucose levels in diabetic rats. This improvement in blood glucose levels causes an improvement in the level of HbA1c. Administration of karamunting fraction can prevent AGEs deposition in renal tissue, which in turn will inhibits the inflammation and prevents further damage of kidneys.

Conclusion: Karamunting fraction can improve blood glucose regulation so that it can prevent further damage and complications of kidney organs in diabetic rats.

Bioactive Compounds and Evaluation of Antioxidant, Cytotoxic and Cytoprotective Effects of Murici Pulp Extracts (Byrsonima crassifolia) Obtained by Supercritical Extraction in HepG2 Cells Treated with H2O2

The use of clean technologies in the development of bioactive plant extracts has been encouraged, but it is necessary to verify the cytotoxicity and cytoprotection for food and pharmaceutical applications. Therefore, the objective of this work was to obtain the experimental data of the supercritical sequential extraction of murici pulp, to determine the main bioactive compounds obtained and to evaluate the possible cytotoxicity and cytoprotection of the extracts in models of HepG2 cells treated with H2O2. The murici pulp was subjected to sequential extraction with supercritical CO2 and CO2+ethanol, at 343.15 K, and 22, 32, and 49 MPa. Higher extraction yields were obtained at 49 MPa. The oil presented lutein (224.77 µg/g), oleic, palmitic, and linoleic, as the main fatty acids, and POLi (17.63%), POO (15.84%), PPO (13.63%), and LiOO (10.26%), as the main triglycerides. The ethanolic extract presented lutein (242.16 µg/g), phenolic compounds (20.63 mg GAE/g), and flavonoids (0.65 mg QE/g). The ethanolic extract showed greater antioxidant activity (122.61 and 17.14 µmol TE/g) than oil (43.48 and 6.04 µmol TE/g). Both extracts did not show cytotoxicity and only murici oil showed a cytoprotective effect. Despite this, the results qualify both extracts for food/pharmaceutical applications.

Antimicrobial Activity of Methanolic and Aqueous Extract of Rhodomyrtus tomentosa Leaves against Staphylococcus aureus and Escherichia coli

Food poisoning is one of the riskiest illnesses caused by an organism like bacteria, viruses and parasites, which can contaminate food at any stage of food production. Most reports are associated with bacterial contamination through the food preparation process. Researcher nowadays attempts to discover a safer agent to use in food preparation as a food preservative agent. Thus, the potential of Rhodomyrtus tomentosa leaves as an antimicrobial agent was explored in this study. It was tested against two bacteria which are Staphylococcus aureus (gram-positive) and Eschericia coli (gram-negative). Antimicrobial activity of methanol and aqueous R. tomentosa leaves extract was compared using gram staining, bacterial identification, antimicrobial sensitivity testing (AST), minimal inhibitory concentration (MIC), minimal bactericidal concentration (MBC) and statistical analysis. The disc diffusion technique was used for AST where the mean area of inhibition methanol and aqueous extract against S. aureus was 18 mm and 16 mm respectively, whereas there was no area of inhibition for E. coli. MIC was done to determine the minimum concentration of the extract needed to inhibit the bacteria. After that, MBC was performed to confirm the previous MIC result. Statistical analysis was done by conduct it through SPSS software program. Then, the result for S. aureus is obtained from finding its p-value. Statistically, a significant difference between the two bacteria was analyzed by using independent t-test. A result of p-value less than 0.05 was considered significantly different as one another. Statistical analysis showed no significant difference between methanol and aqueous extract on antimicrobial activity. In conclusion, both aqueous and methanol leaves R. tomentosa yielded similar antibacterial activity which susceptible to S. aureus and can be used safely toward foodborne pathogen.

Red Arils of Taxus baccata L.-A New Source of Valuable Fatty Acids and Nutrients

The aim of this study, focused on the nutritional value of wild berries, was to determine the contents of macronutrients, profiles of fatty (FAs) and amino acids (AAs), and the contents of selected elements in red arils (RA) of Taxus baccata L., grown in diverse locations in Poland. Protein (1.79–3.80 g/100 g) and carbohydrate (18.43–19.30 g/100 g) contents of RAs were higher than in many cultivated berries. RAs proved to be a source of lipids (1.39–3.55 g/100 g). Ten out of 18 AAs detected in RAs, mostly branched-chain AAs, were essential AAs (EAAs). The EAAs/total AAs ratio approximating were found in animal foods. Lipids of RA contained seven PUFAs, including those from n-3 family (19.20–28.20 g/100 g FA). Polymethylene-interrupted FAs (PMI-FAs), pinolenic 18:3Δ5,9,12; sciadonic 20:3Δ5,11,14, and juniperonic 20:4Δ5,11,14,17, known as unique for seeds of gymnosperms, were found in RAs. RAs may represent a novel dietary source of valuable n-3 PUFAs and the unique PMI-FAs. The established composition of RAs suggests it to become a new source of functional foods, dietary supplements, and valuable ingredients. Because of the tendency to accumulate toxic metals, RAs may be regarded as a valuable indicator of environmental contamination. Thus, the levels of toxic trace elements (Al, Ni, Cd) have to be determined before collecting fruits from natural habitats.

Physico-chemical characterization of Cornus kousa Burg. fruit: determining optimal maturity for fresh consumption

BACKGROUND

Japanese dogwood (Cornus kousa Burg.) is a popular ornamental plant which develops edible compound fruit utilized in traditional Asian medicine. Previous compositional studies have focused on a small fraction of secondary metabolites at a single maturity stage. In order to address the question of optimal ripeness of Japanese dogwood fruit for consumption the study provides a comprehensive insight into its primary and secondary metabolic profile.

RESULTS

The aim of the study was to investigate biochemical composition and morphological traits of Japanese dogwood (Cornus kousa Burg.) fruit at four maturity stages: GF, green fruit; BF, fruit with a defined red blush; RF, ripe fruit; OF, over-ripe fruit. Fruit was characterized by a nearly spherical shape, decreased water content in later stages of ripeness and highest a* values at RF and OF stages. Total sugars increased significantly from GF to OF stage and total organic acids and vitamin C decreased with maturation. Japanese dogwood fruit was characterized by four major phenolic groups: anthocyanins (three), flavonols (eight) hydroxycinnamic acids (three) and flavonoids (one) as well as by four lipophilic antioxidants: tocopherols (two), xanthophylls (five), carotenes (two) and chlorophylls (two). The progression of fruit ripening caused faster accumulation of individual phenolic compounds and lipophilic antioxidants which resulted in significantly higher total phenolic content at the RF and OF stages.

CONCLUSION

Japanese dogwood fruit is a rich alternative source of ascorbic acid, α-tocopherol, flavonols and anthocyanins and should be consumed fresh at fully developed red colour of compound berries when their composition is optimal. © 2020 Society of Chemical Industry.

The Toxic Impact of Honey Adulteration: A Review

Honey is characterized as a natural and raw foodstuff that can be consumed not only as a sweetener but also as medicine due to its therapeutic impact on human health. It is prone to adulterants caused by humans that manipulate the quality of honey. Although honey consumption has remarkably increased in the last few years all around the world, the safety of honey is not assessed and monitored regularly. Since the number of consumers of honey adulteration have increased in recent years, their trust and interest in this valuable product has decreased. Honey adulterants are any substances that are added to the pure honey. In this regard, this paper provides a comprehensive and critical review of the different types of adulteration, common sugar adulterants and detection methods, and draws a clear perspective toward the impact of honey adulteration on human health. Adulteration increases the consumer's blood sugar, which can cause diabetes, abdominal weight gain, and obesity, raise the level of blood lipids and can cause high blood pressure. The most common organ affected by honey adulterants is the liver followed by the kidney, heart, and brain, as shown in several in vivo research designs.

Rhodomyrtus tomentosa Fruit Extract and Skin Microbiota: A Focus on C. acnes Phylotypes in Acne Subjects

Knowing that Rhodomyrtus tomentosa is known to have antibacterial effects, this study investigated the skin microbiota with a focus on Cutibacterium acnes (C. acnes) phylotypes in subjects with acne, and determined microbiota changes after 28 days of treatment with berries Rhodomyrtus tomentosa as an active ingredient (RT). Skin swabs from seventeen acne subjects were collected and the skin microbiome was analyzed using 16S rRNA gene sequencing. A culture-independent next-generation sequencing (NGS)-based SLST (single-locus sequence typing) approach was aimed at evaluating RT extract effects on C. acnes phylotype repartition. Clinical evaluations (lesion counts) were performed at baseline (D0) and after 28 days (D28) of twice-daily application of the RT active ingredient. We determined: (1) the skin microbiota at D0 was dominated by Actinobacteria followed by Firmicutes and Proteobacteria; (2) at the genus level, Cutibacterium was the most abundant genus followed by Staphylococcus and Corynebacterium; (3) C. acnes was the major species in terms of mean abundance, followed by Staphylococcus epidermidis (S. epidermidis) and Staphylococcus hominis (S. hominis); and (4) phylotype IA1 was most represented, with a predominance of SLST type A1, followed by phylotypes II, IB, IA2, IC, and III. After 28 days of RT extract treatment, phylotype repartition were modified with a decrease in abundance (approximately 4%) of phylotype IA1 and an increase in phylotype II and III. Cutibacterium granulosum (C. granulosum) abundance also decreased. Reduction of retentional and inflammatory lesions was also noted only after RT treatment; thus, RT extract acts as a microbiota-regulating agent.

Canjiqueira Fruit: Are We Losing the Best of It?

Fruits and byproducts are valuable sources of nutrients and bioactive compounds, which are associated with a decreased risk of developing several diseases, such as cancer, inflammation, cardiovascular diseases, and Alzheimer’s. The fruits of canjiqueira (Byrsonima cydoniifolia) are already exploited as a food resource, while the seeds are discarded. This study aimed at showing the potential of the whole fruit of canjiqueira. Elemental characterization was performed on ICP OES, while thermal stability was assessed on thermogravimetry. The determination of the fatty acid profile was carried out on gas chromatography and bioactive compound identification using liquid chromatography and mass spectrometry. Results show that both parts of canjiqueira fruit are a source of various minerals, such as Ca, Cu, Fe, K, Mg, and Mn while the seed only is a good source for Zn. Oleic and linoleic acids are the main compounds in pulp and seed. The thermal stability of seed oil is superior to pulp oil, while piceatannol concentration is higher in seed than pulp. All parts of canjiqueira fruit may be used as a strategy to address nutrition issues and are valuable ingredients to prospective food products.

Optimization of Bioactive Compound Extraction from Rose Myrtle Fruit (Rhodomyrtus tomentosa, (W.Ait), Myrtaceae) as the Antioxidant Source

Rose myrtle fruit (Rhodomyrtus tomentosa, (W.Ait), Myrtaceae) is one of fruits widely found in Kalimantan. This fruit contains a bioactive compound that has a potential to be used as medicine. The aim of this study was to obtain optimal temperature and time of extraction in maintaining and protecting the bioactive compound in rose myrtle fruit extract by using water as solvent. This research applied the response surface method with central composite design for two factors, namely, X₁ (temperature/°C) consisting of three levels: 70, 80, and 90°C and X₂ (time/minute) which consisted of three levels of 60, 90, and 120 minutes. Research parameters included total phenol and antioxidant activity. Moreover, GC-MS was used for the characterization of the chemical compound component contained in rose myrtle fruit extract. Optimization of extraction condition resulted in an optimum temperature for extraction of 80.43°C and optimum time for extraction of 85 minutes with an optimum yield of total phenol of 73.77 mg/100 g fresh fruit and antioxidant activity of 1.0385 µg/ml with desirability of 0.892 or 89.2%.

Triketone-terpene meroterpenoids from the leaves of Rhodomyrtus tomentosa

Eight new meroterpenoids (1-8) featuring β-triketone-conjugated terpenoids, rtomentones A-H, were isolated from the leaves of Rhodomyrtus tomentosa. Structures of the isolates were unambiguously established by a combination of NMR and ECD spectroscopy and X-ray diffraction analysis. Rtomentone C (3) was the first example of aromadendrane-based meroterpenoid containing an oxa-spiro[5.6] ring. Rtomentone D (4) was obtained as a racemic mixture confirmed by chiral HPLC analysis. The cytotoxicity against MDA-MB-231, A549, and DLD-1 cells of all isolates was evaluated.

The Health Beneficial Properties of Rhodomyrtus tomentosa as Potential Functional Food

Rhodomyrtus tomentosa (Aiton) Hassk. is a flowering plant belonging to the family Myrtaceae, native to southern and southeastern Asia. It has been used in traditional Vietnamese, Chinese, and Malaysian medicine for a long time for the treatment of diarrhea, dysentery, gynecopathy, stomachache, and wound healing. Moreover, R. tomentosa is used to make various food products such as wine, tea, and jam. Notably, R. tomentosa has been known to contain structurally diverse and biologically active metabolites, thus serving as a potential resource for exploring novel functional agents. Up to now, numerous phenolic and terpenoid compounds from the leaves, root, or fruits of R. tomentosa have been identified, and their biological activities such as antioxidant, antibacterial, anti-inflammatory, and anticancer have been evidenced. In this contribution, an overview of R. tomentosa and its health beneficial properties was focused on and emphasized.

Poly(vinyl alcohol) electrospun nanofibers containing antimicrobial Rhodomyrtus tomentosa extract

Electrospun nanofibers were prepared from Rhodomyrtus tomentosa extract and poly(vinyl alcohol). The antimicrobial effect was assessed against two Gram-negative bacterial strains ( Escherichia coli, Pseudomonas aeruginosa) and two Gram-positive bacterial strains ( Bacillus subtilis, Enterococcus faecalis) by paper disc diffusion method. Ethyl acetate extract of R. tomentosa was selected for fabrication of nanofibers because it shows the most active antimicrobial activity with zone of inhibition ranging from 9.33 ± 0.21 to 13.67 ± 0.32 mm. The presence of high abundance of myricetin and rhodomyrtone might contribute to the antibiotic activity against all tested bacterial strains. The average diameter of the R. tomentosa extract/poly(vinyl alcohol) nanofibers increased from 120.4 to 214.8 nm with increasing concentration of R. tomentosa extract from 0.5% to 2.5%. The antimicrobial activity of R. tomentosa extract/poly(vinyl alcohol) nanofibers was relatively higher at concentration of the extract (1.5% and 2.5%) against all test organisms with a clear zone of inhibition 7–12 mm. The results demonstrated that R. tomentosa extract/poly(vinyl alcohol) electrospun nanofibers are an interesting platform for delivery of bioactive compounds as wound dressing or other strategies for combating bacterial infections.

Cytotoxic and anti-inflammatory active phloroglucinol derivatives from Rhodomyrtus tomentosa

Seven undescribed phloroglucinol derivatives, tomentodiones N-T, and eleven known ones were isolated from Rhodomyrtus tomentosa. Tomentodione N is the first example of a β-triketone unit coupled with an isoamyl alcohol through a furan fused-ring, and tomentodiones N, S, T were three racemates. The undescribed structures were elucidated by means of spectroscopic, X-ray diffraction, electronic circular dichroism calculation, and chemical methods. In addition, the isolated compounds were determined for the cytotoxic activities on HeLa cells and anti-inflammatory activities in LPS-stimulated RAW 264.7 cells.

Watsonianone A from Rhodomyrtus tomentosa Fruit Attenuates Respiratory-Syncytial-Virus-Induced Inflammation In Vitro

Respiratory syncytial virus (RSV) is one of the most common respiratory pathogens. Immoderate inflammation plays a great role in causing RSV-induced diseases. In the present study, watsonianone A, isolated from the fruit of Rhodomyrtus tomentosa (Ait.) Hassk, was found to show a good inhibitory effect on RSV-induced NO production, with a half-maximal inhibitory concentration of 37.2 ± 1.6 μM. Enzyme-linked immunosorbent assay and fluorescence quantitative polymerase chain reaction analyses indicated that watsonianone A markedly reduced both mRNA and protein levels of tumor necrosis factor α, interleukin 6, and monocyte chemoattractant protein 1 in RSV-infected RAW264.7 cells. Mechanistically, watsonianone A inhibited nuclear factor κB (NF-κB) activation by suppressing IκBα phosphorylation. Further analysis revealed that watsonianone A activated the thioredoxin system and decreased intracellular reactive oxygen species (ROS) levels, which are closely associated with NF-κB activation in RSV-infected cells. These results reveal that watsonianone A can attenuate RSV-induced inflammation via the suppression of ROS-sensitive inflammatory signaling.

Potential Bio-Control Agent from Rhodomyrtus tomentosa against Listeria monocytogenes

Listeria monocytogenes is an important foodborne pathogen implicated in many outbreaks of listeriosis. This study aimed at screening for the potential use of Rhodomyrtus tomentosa ethanolic leaf extract as a bio-control agent against L. monocytogenes. Twenty-two L. monocytogenes isolates were checked with 16 commercial antibiotics and isolates displayed resistance to 10 antibiotics. All the tested isolates were sensitive to the extract with inhibition zones ranging from 14 to 16 mm. Minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) values ranged from 16 to 32 µg/mL and 128 to 512 µg/mL, respectively. Time-kill assay showed that the extract had remarkable bactericidal effects on L. monocytogenes. The extract at a concentration of 16 µg/mL reduced tolerance to 10% NaCl in L. monocytogenes in 4 h. Stationary phase L. monocytogenes cells were rapidly inactivated by greater than 3-log units within 30 min of contact time with R. tomentosa extract at 128 µg/mL. Electron microscopy revealed fragmentary bacteria with changes in the physical and morphological properties. Our study demonstrates the potential of the extract for further development into a bio-control agent in food to prevent the incidence of L. monocytogenes contamination.

Fatty acids composition of Spanish black (Morus nigra L.) and white (Morus alba L.) mulberries

This research has determined qualitatively and quantitatively the fatty acids composition of white (Morus alba) and black (Morus nigra) fruits grown in Spain, in 2013 and 2014. Four clones of each species were studied. Fourteen fatty acids were identified and quantified in mulberry fruits. The most abundant fatty acids were linoleic (C18:2), palmitic (C16:0), oleic (C18:1), and stearic (C18:0) acids in both species. The main fatty acid in all clones was linoleic (C18:2), that ranged from 69.66% (MN2) to 78.02% (MA1) of the total fatty acid content; consequently Spanish mulberry fruits were found to be rich in linoleic acid, which is an essential fatty acid. The fatty acid composition of mulberries highlights the nutritional and health benefits of their consumption.