Potential Of Secondary Metabolites Research Articles

Unearthing the Potential Secondary Metabolites Isolated from the Fungus Aspergillus flocculosus : A Comprehensive Review.

Unearthing the Potential Secondary Metabolites Isolated from the Fungus Aspergillus flocculosus : A Comprehensive Review.

Polar Fungi Pseudogymnoascus: Secondary Metabolites and Ecological Significance

Fun gi are widely distributed organisms known to produce secondary metabolites and other biochemical compounds. However, fungi from the polar regions with extreme environmental conditions such as low temperatures, high ultra-violet exposure, nutrient scarcity, and dryness are understudied. They produced many secondary metabolites that are yet to be identified, to adapt and survive the extreme conditions. These polar fungi with potential in secondary metabolites are promising in biotechnological applications such as pharmaceutical, textile, and food manufacturing. Pseudogymnoascus is a genus within the Pseudeurotiaceae family that has been reported in the Antarctic regions. This genus plays an important role in the decomposition process in the polar regions. To date, there are 24 species identified within the genus Pseudogymnoascus in the world. The true potential of Pseudogymnoascus, especially those from the polar region, is yet to be explored. This review gives an overview of the polar Pseudogymnoascus spp. Based on their secondary metabolites production and understanding their ecological perspective in the extreme environment.

Exploring the Potential of Bacillus Species Secondary Metabolites as SARS-CoV-2 Protease Inhibitors

Exploring the Potential of Bacillus Species Secondary Metabolites as SARS-CoV-2 Protease Inhibitors

Antifungal Potential of Secondary Metabolites Derived from Arcangelisia flava (L.) Merr.: An Analysis of In Silico Enzymatic Inhibition and In Vitro Efficacy against Candida Species

Considering the escalating resistance to conventional antifungal medications, it is critical to identify novel compounds that can efficiently counteract this challenge. The purpose of this research was to elucidate the fungicidal properties of secondary metabolites derived from Arcangelisia flava, with a specific focus on their efficacy against Candida species. This study utilized a combination approach comprising laboratory simulations and experiments to discern and evaluate the biologically active constituents present in the dichloromethane extract of A. flava. The in vitro experiments demonstrated that compounds 1 (palmatine) and 2 (fibraurin) exhibited antifungal properties. The compounds exhibited minimum inhibitory concentrations (MICs) ranging from 15.62 to 62.5 µg/mL against Candida sp. Moreover, compound 1 demonstrated a minimum fungicidal concentration (MFC) of 62.5 µg/mL against Candida glabrata and C. krusei. In contrast, compound 2 exhibited an MFC of 125 µg/mL against both Candida species. Based on a molecular docking study, it was shown that compounds 1 and 2 have a binding free energy of −6.6377 and −6.7075 kcal/mol, respectively, which indicates a strong affinity and specificity for fungal enzymatic targets. This study utilized pharmacophore modeling and Density Functional Theory (DFT) simulations to better understand the interaction dynamics and structural properties crucial for antifungal activity. The findings underscore the potential of secondary metabolites derived from A. flava to act as a foundation for creating novel and highly efficient antifungal treatments, specifically targeting fungal diseases resistant to existing treatment methods. Thus, the results regarding these compounds can provide references for the next stage in antifungal drug design. Further investigation is necessary to thoroughly evaluate these natural substances’ clinical feasibility and safety characteristics, which show great potential as antifungal agents.

Identification of Secondary Metabolites from Actinomycetes Isolated from the Hilly Region of Nepal

Actinomycetes are a unique class of Gram-positive bacteria with a fungus-like filamentous mycelium. They are often called ‘antibiotics factories’ because they can produce many potent secondary metabolites. At present, multidrug-resistant (MDR) pathogens are the main problem for humans and animals and to overcome this problem, more potent antibiotics are urgently required. Fortunately, Nepal has great geographical and climatic diversity serving as a home for various actinomycetes. This study identified several actinomycetes using morphological and biochemical assays from seven soil samples collected from different elevations in Nepal. The primary objective of this study was to screen the potent metabolites-producing actinomycetes. For this purpose, antimicrobial assays of seven isolates were carried out against Escherichia coli ATCC 25922, Salmonella typhi ATCC 14028, Shigella sonnei ATCC 25931, and Staphylococcus aureus ATCC 43300. The sample BT36 demonstrated the highest zone of inhibition against the tested microorganisms among others. Similarly, minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of all isolates were carried out. Among them, the MIC of samples BT36, PT7, and AB1 were found to be 1.952 mg/mL, 0.012 mg/mL, and 0.029 mg/mL, respectively. Ethyl acetate extracts of resulting potent isolates PT7 and AB1 were subjected to mass spectrometric analysis. A total of 22 bioactive compounds were annotated from liquid chromatography-high resolution mass spectroscopy (LC-HRMS), including epopromycin A, myxopyronin B, gilvocarcin HE, and okilactomycin A. It is concluded that this study will be useful in setting up a strategy to isolate useful secondary metabolites from soil microbes from the hilly region of Nepal.

Exploring the therapeutic potential of Cynanchum tunicatum (Retz.) Alston- assessment of phytochemicals and biological activities

Cynanchum tunicatum (Retz.) Alston is native to the Asian region and is distributed in the tropical areas of India and Sri Lanka. The aim of this study is to explore the phytochemical composition, antioxidant potential, and anti-inflammatory properties of C. tunicatum. Metabolic profiling was carried out using phytochemical screening to detect and quantify the secondary metabolites. To evaluate the potential secondary metabolites using the standard methods, Fourier transform infrared (FTIR), High-Performance Thin Layer Chromatography (HPTLC) and Gas Chromatography–Mass Spectrometry (GC–MS) from organic extracts of C. tunicatum and its biological activities. FTIR investigated peaks that represent alkane and aromatic compounds. GC–MS revealed the presence of 22 constituents such as 1-Hexacosene (0.145 %), l-(+)-Ascorbic acid 2,6-dihexadecanoate (8.129 %), Campesterol (5.243 %), Beta −Amyrin (10.614 %), Lupeol (13.061 %), Octadecanoic acid (0.751 %) are the major active compounds present. HPTLC fingerprinting confirms the bioactive compounds such as colchicine, strychnine, coumarin etc. which are represented with corresponding Rf values. Among all the extracts of C. tunicatum methanolic extract showed highest antioxidant activities. In 2,2-diphenylpicrylhydrazyl method exhibit the IC50 of (38.91 µg/mL), Ferric reducing antioxidant power assay (1.6 µg/mL), total antioxidant assay (IC50 = 32.91 µg/mL) and IC50 of anti-inflammatory activity (42.31 µg/mL) respectively. These findings enrich the knowledge of the species Cynanchum tunicatum for the possible application as a source of bioactive compounds in drug discovery.

Species-level distribution of microbiota with secondary metabolic potential in Chinese Baijiu fermentation

Chinese Baijiu fermentation is a typical spontaneous fermentation with complex microbial community. However, the species-level distribution of microbiota with secondary metabolic potential in Baijiu fermentation has not been well studied so far. In this study, taking soy sauce aroma type Baijiu and light aroma type Baijiu fermentations as examples, we identified 1575 biosynthetic gene clusters (BGCs) belonging to 874 gene cluster families (GCFs) through metagenomic analysis. Bioactivity prediction analysis revealed 210 BGCs producing potential bioactive secondary metabolites (probabilities of bioactivities ≥70%). We recovered 66 bacterial metagenome-assembled genomes (MAGs) to explore distribution of bioactive secondary metabolites at a higher resolution taxonomic level. A total of 16 MAGs were identified as BGC-rich MAGs (>3 BGCs), and they belonged to 11 genera. Four MAGs, annotated to be Bacillus velezensis, Bacillus licheniformis, Kroppenstedtia eburnea and Kroppenstedtia spp., contained more than 3 BGC-producing potential bioactive secondary metabolites and had more than 1 counts per million (CPM) abundance in fermentations. They were identified as the potential producers of bioactive secondary metabolites. This study contributed to characterising the diversity and distribution of microbiota with secondary metabolic potential in Baijiu fermentation, and mining novel secondary metabolites and their producers.

Fermented Rapeseed and Soybean Alone and in Combination with Macro Algae Inhibit Human and Pig Pathogenic Bacteria In Vitro.

Higher plants produce secondary metabolites expressing antimicrobial effects as a defense mechanism against opportunistic microorganisms living in close proximity with the plant. Fermentation leads to bioconversion of plant substrates to these bioactive compounds and their subsequent release via breakdown of plant cell walls. Fermented feed products have recently started to become implemented in the pig industry to reduce overall disease pressure and have been found to reduce events such as post-weaning diarrhea. In this study, we investigate the antimicrobial potential of fermented soybean- and rapeseed-based pig feed supplements with and without added seaweed. The antimicrobial effect was tested in a plate well diffusion assay against a range of known human and livestock pathogenic bacteria. Further, we investigate the metabolite profiles based on liquid-chromatography mass-spectrometry (LC-MS) analysis of the fermented products in comparison to their unfermented constituents. We observed a pronounced release of potential antimicrobial secondary metabolites such as benzoic acids when the plant material was fermented, and a significantly increased antimicrobial effect compared to the unfermented controls against several pathogenic bacteria, especially Salmonella enterica Typhimurium, Listeria monocytogenes, Yersinia enterocolitica, and a strain of atopic dermatitis causing Staphylococcus aureus CC1. In conclusion, fermentation significantly enhances the antimicrobial properties of rapeseed, soybean, and seaweed, offering a promising alternative to zinc oxide for controlling pathogens in piglet feed. This effect is attributed to the release of bioactive metabolites effective against pig production-relevant bacteria.

Piper longum L. ameliorates gout through the MAPK/PI3K-AKT pathway

Ethnopharmacological relevanceGout, a painful joint disease with a prevalence ranging from 0.86% to 2.2% in China over the past decade. Traditional medicine has long utilized the medicinal and edible Piper longum L. (PL) fruit spikes for treating gout and other joint conditions like rheumatoid arthritis. However, the exact mechanisms behind its effectiveness remain unclear. Aim of the studyThis study aimed to investigate the potential of alcoholic extracts from PL fruit spikes as a safe and effective treatment for gout. We used a combined network pharmacology and experimental validation approach to evaluate the mechanisms behind the anti-gout properties of PL. Materials and methodsUPLC-Q/TOF-MS analysis determined the major components of PL. Subsequently, network pharmacology analysis predicted potential molecular targets and related signaling pathways for the anti-gout activity of PL. Molecular docking simulations further explored the interactions between PL compounds and proteins and characterized the properties of potential bioactive secondary metabolites. Mouse models of air pouch inflammation and hyperuricemia were further established, and the anti-gout mechanism of PL was confirmed by examining the expression of proteins related to the MAPK and PI3K-AKT pathways in the tissue. ResultsOur analysis revealed 220 bioactive secondary metabolites within PL extracts. Network pharmacology and molecular docking results indicated that these metabolites primarily combat gout by modulating the PI3K-AKT and MAPK signaling pathways. In vivo experiments have also proven that PL at a dose of 100 mg/kg can optimally reduce acute inflammation of gout and kidney damage caused by high uric acid. The anti-gout mechanism involves the PI3K-AKT/MAPK signaling pathway and its downstream NF-κB pathway. ConclusionThis study provides compelling evidence for PL's therapeutic potential in gout management by modulating key inflammatory pathways. The findings offer a strong foundation for future clinical exploration of PL as a gout treatment option.

Characterization of a broad-spectrum antifungal strain, Streptomyces graminearus STR-1, against Magnaporthe oryzae.

Fungal diseases such as the devastating rice blast pose severe threats to crop production worldwide. Biological control of crop diseases caused by fungal pathogens is an environment-friendly approach for safeguarding crop production. But the insufficient availability of microbial agents effective against various fungal diseases has hampered the development of green production in crops. In this study, we identified a broad-spectrum antifungal bacterium, Streptomyces graminearus STR-1, showing antagonistic activity to diverse fungal pathogens including Magnaporthe oryzae, Rhizoctonia solani, Fusarium graminearum, Ustilaginoidea virens, and Bipolaris maydis. Its antifungal activity was relatively stable and less affected by temperature and pH. Evaluation of the biocontrol activity of STR-1 revealed that STR-1 prevented and controlled rice blast disease via eliciting plant immunity and suppressing fungal infection-structure development. STR-1 broth extract inhibited spore germination, likely through inhibiting protein synthesis. Combining LC-MS and chromatography analysis of the antimicrobial compounds purified from STR-1 broth extract, together with decoding STR-1 genomic sequence, we identified 4-oxo-4-[(1-phenylethyl)amino]but-2-enoic acid, 1,3,5-Trimethylpyrazole and SMA-1 as the potential main STR-1 secondary metabolites associated with its antifungal effects. This study suggests that bacterial strain STR-1 could be used for identifying highly effective and broad-spectrum secondary metabolites for containing rice blast and other crop diseases. The application of the active compounds offers a promising measure to tackle fungal disease.

Antagonistic Behavior of Streptomyces chartreuse against Pathogenic Bacteria in Ricinus communis L.

ABSTRACT: Antibiotics are a crucial tool in modern medicine and have saved countless lives by effectively treating a wide range of bacterial infections. The microbial antibiotic have several biotechnological applications viz. agriculture, pharmaceuticals, food preservation, animal nutritions. The diverse array of applications and the various roles of bioactive metabolites produced by Actinomycetes have sparked a growing interest in the exploration of unique and unprecedented Actinomycetes strains. The Actinomycetes from soil ecosystem, marine ecosystem, rhizosphere of plant roots are also known to secrete novel antibiotics. In this context, the main objective of this research is to isolate and screen Actinomycetes strains that are capable of producing highly potent culturable secondary metabolites with novel antibacterial properties. These metabolites can potentially serve as biocontrol agents against Xanthomonas infections in Ricinus communis L., offering uncommon and innovative applications within the field of agriculture. All the Actinomycetes isolates were isolated from Mehsana regions of Gujarat an area of over 4,401 km2, with wide microbial diversity and can serve as a source for promising antibiotics producers. 7 rhizospheric soil samples were collected from various region sites viz. Ranasan, Mansa, Panchot, Gozariya, Kansa, Langhnaj, and Kherva. Total 76 antibiotic producing Actinomycetes isolates were obtained in Primary Screening. Based on the results of primary screening, potential morphologically diverse 3 isolates were selected for antibiotic production in liquid medium. FTIR analysis of three samples revealed distinct bands in the spectra. Sample-1 exhibited O-H (1347 cm^-1) and C-N (1191 cm^-1) groups. Sample-2 displayed O-H (3462 cm^-1), C-O (1043 cm^-1), and C=O (1736 cm^-1) groups. Sample-3 showcased O-H (3466 cm^-1), C=O (1737 cm^-1), C-N (1232 cm^-1), and C-O (1043 cm^-1) groups, providing valuable insights into their chemical compositions. The isolate BNPA72 gave best antibiotic production and was identified as Streptomyces chartreusis by 16 s rRNA gene sequencing method. The isolate Streptomyces chartreusis BNPA72 was able to inhibit the plant pathogen Xanthomonas, hence categorized as Biocontrol agents.

Calliandra haematocephala’s phytochemical analysis and antifungal effectiveness against fish pathogen in the lake of Bhopal

Aquaculture has been a major part of our Economy from ancient times and antimycotic resistant fish illnesses have emerged as a major threat in aquaculture from a very long time. As routinely used anti-fungal medications have become less effective and traditional medicinal herbs have been identified as a possible medication source that can counteract antifungal resistance. The current study will look at the antifungal efficacy of leaf and flower extracts of the nutritional and traditional medicinal plant called Calliandra haematocephala against 3 common fish fungal pathogens (Achlya, Saprolegnia and Aphanomyces) that were isolated from Lower Lake of Bhopal (M.P.) and causes illness in fishes present in Lower Lake, Bhopal (M.P.). The leaves and flowers of Calliandra haematocephala were extracted sequentially with ethanol as a solvent, and the presence of possible phytoconstituents was qualitatively evaluated. Flavonoids, phenol, alkaloids, carbohydrates, tannins and saponins were present in both flowers and leaves and steroids were found exclusively in the ethanolic extract of the leaf only not in flower extract. The antifungal activity of ethanolic extract was determined using the agar well diffusion technique. The ethanolic fraction of the flower demonstrated a wide range of activity against fish pathogens, with a maximal inhibitory or clearance activity against Saprolegnia in a amount of 20 μL (4 mm) and in leaves it showed maximum clearance zone in Achlya and Saprolegnia in 20μL (4 mm). In conclusion, Calliandra haematocephala’s extracts consist of potential secondary metabolites that might be employed as antifungal treatments for 3 prevalent fish Pathogens, and the leaf ethanolic extracts have more inhibitory efficacy than the flower ethanolic extract.

Malignance-restriction activity exhibited by bioactive compounds of selected actinobacteria as silver nanoparticles against A549 lung cancer cell lines.

This article deals with the antibacterial and anticancer potential of secondary metabolites produced by actinomycetes also reported as actinobacteria, Microbacterium proteolyticum (MN560041), and Streptomycetes rochei, where preliminary studies were done with the well diffusion method. These actinobacteria's silver nanoparticles were synthesized and characterized using transmission electron microscopy (TEM) and UV-Visible spectroscopy. Anticancer was measured using the MTT test, reactive oxygen species (ROS) generation measured with DCFDA, mitochondrial membrane potential (MMP) measurement, and DAPI fluorescence intensity activity was measured in treated and non-treated cancerous cells. The IC50 value for 5-FU (a), LA2(O) (b), LA2(R) (c), LA2(ON) (d), and LA2(RN) (e) was obtained at 3.91 μg/mL (52.73% cell viability), 56.12 μg/mL (52.35% cell viability), 44.90 μg/mL (52.3% cell viability), 3.45 μg/mL (50.25% cell viability), and 8.05 μg/mL (48.72% cell viability), respectively. TEM micrographs revealed discrete, well-separated AgNPs particles of size 7.88 ± 2 to 12.86 ± 0.24 nm. Gas chromatography-mass spectrometry was also performed to detect the compounds in bioactive metabolites where n-hexadecanoic acid was obtained as the most significant one. MTT test showed a substantial decline in A549 cell viability (up to 48.72%), 2.75-fold increase in ROS generation was noticed in comparison to untreated A549 lung cancer cells when measured with DCFDA. A total of 0.31-fold decrease in MMP and 1.74-fold increase in DAPI fluorescence intensity compared to untreated A549 lung cancer cells suggests that the synthesized nanoparticles promote apoptosis in cancerous cells. Our findings suggests that the secondary metabolites of M. proteolyticum and S. rochei in nanoparticle form can be used as a significant compound against lung cancers.

Evaluation of Adenanthera pavonina-derived compounds against diabetes mellitus: insight into the phytochemical analysis and in silico assays.

Adenanthera pavonina is a medicinal plant with numerous potential secondary metabolites showing a significant level of antidiabetic activity. The objective of the current study was to identify potential phytochemicals from the methanolic leaf extract of Adenanthera pavonina as therapeutic agents against diabetes mellitus using GC-MS and in silico methods. The GC-MS analysis of the leaf extract revealed a total of 17 phytochemicals. Molecular docking was performed using these phytochemicals, targeting the mutated insulin receptor tyrosine kinase (5hhw), which inhibits glucose uptake by cells. Diazoprogesterone (-9.2kcal/mol), 2,4,4,7a-Tetramethyl-1-(3-oxobutyl)octahydro-1H-indene-2-carboxylic acid (-6.9kcal/mol), and 2-Naphthalenemethanol, decahydro-.alpha.,.alpha.,4a-trimethyl-8-methylene-, [2R-(2.alpha.,4a.alpha.,8a.beta.)] (-6.6kcal/mol) exhibited better binding with the target protein. The ADMET analysis was performed for the top three compounds with the best docking scores, which showed positive results with no observed toxicity in the AMES test. Furthermore, the molecular dynamics study confirmed the favorable binding of Diazoprogesterone, 2,4,4,7a-Tetramethyl-1-(3-oxobutyl)octahydro-1H-indene-2-carboxylic acid and 2-Naphthalenemethanol, decahydro-.alpha.,.alpha.,4a-trimethyl-8-methylene-, [2R-(2.alpha.,4a.alpha.,8a.beta.)] with the receptor throughout the 100ns simulation period.

Aktivitas Antibakteri dan Antioksidan dari Senyawa Bioaktif Asal Bakteri Endofit Tanaman Nyatoh (Palaquium amboinense B.)

Nyatoh plant (Palaquium amboinense B.) is native to Indonesia which is known to have the ability to produce potential secondary metabolites. The aim of this study was to evaluate the antibacterial and antioxidant activities from bioactive compounds produced by endophytic bacteria from nyatoh leaves. Five endophytic bacteria were tested against 4 targeted bacteria including Escherichia coli ATCC 8739, Pseudomonas aeruginosa ATCC 15442, Bacillus subtilis ATCC 19659, and Staphylococcus aureus ATCC 6538. Bacterial isolate which had the strongest antibacterial activity was then fermented and extracted. The corresponding extract was further tested on disc diffusion method, determination of Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC) values, antioxidant evaluation, and analyzed for its bioactive compound components via GC-MS analysis. The results showed that one isolate, namely D1 can produce secondary metabolite which act as antibacterial and antioxidant potentials. This corresponding extract has the strongest MIC and MBC against B. subtilis with value of 39.5 and >78.1 µg/ml and exhibited antioxidant activity against 2,2-difenil-1-pikrilhidrazil (DPPH) with inhibition value of 85.37%. Based on GC-MS analysis, secondary metabolites derived from this potential extract contained some major active constituents including Tributyl acetylcitrate and bis (2-ethylhexyl) ester which might act as antibacterial and antioxidant agents.

Resveratrol as a Promising Nutraceutical: Implications in Gut Microbiota Modulation, Inflammatory Disorders, and Colorectal Cancer.

Natural products have been a long-standing source for exploring health-beneficial components from time immemorial. Modern science has had a renewed interest in natural-products-based drug discovery. The quest for new potential secondary metabolites or exploring enhanced activities for existing molecules remains a pertinent topic for research. Resveratrol belongs to the stilbenoid polyphenols group that encompasses two phenol rings linked by ethylene bonds. Several plant species and foods, including grape skin and seeds, are the primary source of this compound. Resveratrol is known to possess potent anti-inflammatory, antiproliferative, and immunoregulatory properties. Among the notable bioactivities associated with resveratrol, its pivotal role in safeguarding the intestinal barrier is highlighted for its capacity to prevent intestinal inflammation and regulate the gut microbiome. A better understanding of how oxidative stress can be controlled using resveratrol and its capability to protect the intestinal barrier from a gut microbiome perspective can shed more light on associated physiological conditions. Additionally, resveratrol exhibits antitumor activity, proving its potential for cancer treatment and prevention. Moreover, cardioprotective, vasorelaxant, phytoestrogenic, and neuroprotective benefits have also been reported. The pharmaceutical industry continues to encounter difficulties administering resveratrol owing to its inadequate bioavailability and poor solubility, which must be addressed simultaneously. This report summarizes the currently available literature unveiling the pharmacological effects of resveratrol.

In Silico Analysis of Novel Bacterial Metabolites with Anticancer Activities.

Resistance to anticancer therapeutics is a major global concern. Thus, new anticancer agents should be aimed against novel protein targets to effectively mitigate the increased resistance. This study evaluated the potential of secondary metabolites from a bacterial endophyte, as new anticancer agents, against a novel protein target, fibroblast growth factor. In silico genomic characterization of the Bacillus sp. strain MHSD_37 was used to identify potential genes involved in encoding secondary metabolites with biological activity. The strain was also exposed to stress and liquid chromatography-mass spectrometry used for the identification and annotation of secondary metabolites of oligopeptide class with anticancer activity. Selected metabolites were evaluated for their anticancer activity through molecular docking and Absorption, Distribution, Metabolism, Excretion and Toxicity (ADMET) properties analysis. Phylogenetic analysis revealed that strain MHSD_37 shared close evolutionary relationships with Bacillus at the species level, with no identified relationships at the sub-species level. Both in silico genomic characterization and spectrometry analysis identified secondary metabolites with potential anticancer activity. Molecular docking analysis illustrated that the metabolites formed complexes with the target protein, fibroblast growth factor, which were stabilized by hydrogen bonds. Moreover, the ADMET analysis showed that the metabolites passed the toxicity test for use as a potential drug. Thereby, Bacillus sp. strain MHSD_37 is a potential novel strain with oligopeptide metabolites that can be used as new anticancer agents against novel protein targets.

Assessment of Endophytic Fungal Community in Palm Leaves and Their Biocontrol Potential

Microbial endophytes live asymptomatically within a host plant and contribute positively to its fitness. Endophytes associate ubiquitously with all plants examined so far and form an integral part of the host for processes such as nutrient uptake and stress response and traits like disease resistance. Well-characterized host–endophyte interaction models exist, but little is known about the microbiome of the monocot plant host, palm. In this study, we identified the endophytic fungal community associated with mule palm leaves with an objective to test their antagonist effects on lethal pathogens of palms. The leaflets of mule palms were sampled across five sites in Central and South Florida, and fungal endophytes were identified using culture-dependent (CD) and amplicon sequence-based culture-independent (CI) methods. Operational taxonomic units (OTUs) corresponding to phylum Ascomycota were identified by both approaches, whereas Basidiomycota were only detected using the CI method. Among the ascomycetes, a small (22%) overlap in the OTUs at the genus level was observed between the two methods, whereas the majority (64%) of OTUs were detected using the CI approach. In vitro cocultivation of endophytes with palm pathogens was observed to produce three distinct interaction phenotypes: inhibition zone, niche establishment, and overlapping growth. Eight endophytes capable of inhibiting fungal pathogen growth in vitro were also identified, suggesting a biocontrol potential for endophyte-derived secondary metabolites. A better understanding of the composition, assembly, and ecology of palm-associated microbial communities would eventually lead to healthy and resilient palms. [Formula: see text] Copyright © 2024 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license .

The potential Two Types of Green Macroalgae (Caulerpa racemose and Caulerpa lentillifera) as a Natural Food Preservative from Jepara beach, Indonesia

Green macroalgae, known locally as Latoh, is one of the green seaweeds consumed by the local community in Jepara and is beneficial for health. This study explores the potential of secondary metabolites from seaweed and its symbiotic bacteria as natural food preservatives and antibacterials. Seaweed samples were collected from the seagrass ecosystem of Panjang Island, Jepara, Indonesia. Subsequently, the samples were subjected to scanning electron microscopy analysis, proximate analysis, phytochemical analysis, thin layer chromatography, and high-performance liquid chromatography for amino acid analysis. A sample was subjected to a multistage extraction process using n-hexane, ethyl acetate, and methanol (1:5 w/v), each for 24 h. Symbiotic bacteria from seaweed were isolated, and enzymatic (proteolytic, amylolytic, and cellulolytic) and antibacterial testing against pathogenic bacteria Staphylococcus aureus and Escherichia coli was conducted using the disc diffusion method. The selected bacteria were subjected to molecular identification. The research showed that Caulerpa lentillifera had an ash content of 3.24 %, protein content of 0.57 %, and fat content of 0.337 %. Phytochemical analysis shows that the sample contains flavonoids, steroids, and alkaloids. HPLC analysis reveals that Caulerpa lentillifera has the highest content of aspartic acid (relative area: 11.90 %), glutamic acid (relative area: 13.43 %), and alanine (relative area: 9.03 %). Caulerpa racemosa sample shows the highest detector response for glutamic acid (relative area: 12.19%), aspartic acid (relative area: 11.10 %), and alanine (relative area: 9.63 %). The results indicate that 14 bacterial isolates were successfully isolated, with 6 isolates from Caulerpa lentillifera and 8 isolates from Caulerpa racemosa, all exhibiting enzymatic and antibacterial abilities. The research results concluded that the Latoh seaweed species Caulerpa lentillifera and Caulerpa racemosa and their symbiotic bacteria have the potential to be used as food preservatives. HIGHLIGHTS HPLC analysis showed that Caulerpa lentillifera had the highest content of aspartic acid, glutamic acid, and alanine. Caulerpa racemosa also had high levels of glutamic acid, aspartic acid, and alanine The research successfully isolated 14 bacterial isolates, with 6 isolates from Caulerpa lentillifera and eight isolates from Caulerpa racemosa, all exhibiting enzymatic and antibacterial abilities Molecular identification revealed the presence of identified bacteria such as Pseudoalteromonas arabiensis, Pseudoalteromonas piscicida, Pseudoalteromonas shioyasakiensis, and Vibrio alginolyticus seaweed species Caulerpa lentillifera and Caulerpa racemosa, along with their symbiotic bacteria, have the potential to be used as natural food preservatives due to their antibacterial and enzymatic pro perties GRAPHICAL ABSTRACT

Secondary Metabolites from Symbiotic Bacteria of Seagrass and Molluscs as A Reference for Natural Food Preservatives

Symbiotic bacteria from seagrass and molluscs have the potential to be a source of secondary metabolites. Compounds from these secondary metabolites, such as natural food preservatives, can be used in the bioindustry sector. This research aims to identify the potential secondary metabolites from symbiotic bacteria in molluscs and seagrass that can support the Sustainable Development Goals (SDG) public health program. The samples used in this study were symbiotic bacteria of mollusc from seagrass environments, symbiotic bacteria from seagrass, and seagrass samples. The seagrass samples were analysed phytochemically, while the symbiotic bacteria samples from molluscs and seagrass were tested for their antibacterial activity against food spoilage pathogens such as Staphylococcus aureus and Escherichia coli using the disc diffusion method. Bacteria that showed potential antibacterial activity were identified using molecular methods, and the content of active compounds was analysed using gas chromatography-mass spectrometry. The phytochemical analysis revealed that seagrass contains flavones, tannins, steroids, and compounds with potential antibacterial properties. GC-MS analysis indicated that seagrass is predominantly composed of unsaturated fatty acids, which have antimicrobial effects by damaging bacterial cell membranes and disrupting the function of enzymes essential for growth and reproduction. Ten symbiotic bacteria isolates demonstrated proteolytic, cellulolytic, and lipolytic enzyme activity, suggesting their potential as antibacterial agents due to their ability to break down cell walls. Molecular identification of selected bacteria revealed the presence of mollusc symbionts, including Vibrio owensii, Bacillus paramycoides, and Pseudoalteromonas flavipulchra. The symbiotic bacteria found in seagrass in this study included Bacillus velezensis, Bacillus paramycoides, Nocardiopsis alba, Nocardiopsis alba, Bacillus tropicus, Lysinibacillus fusiformis, and Bacillus tropicus. GC-MS analysis of selected symbiotic bacteria from seagrass showed that the dominant compound components were phthalic acid, bis(7-methyl octyl) ester (25.18, 43.84, 35.55 %), and trimethoxy-3-piperidyl-2,2'-binaphthalene-1,1',4,4'-tetrone (36.36, 47.71, 64.48 %). In conclusion, seagrass and its symbiotic bacteria, as well as symbiotic bacteria from molluscs living in seagrass, have the potential to serve as antibacterial agents and can be used as references for food preservatives. HIGHLIGHTS Seagrass and mollusc symbiotic bacteria produce secondary metabolites that have antimicrobial properties, making them suitable for food preservation The component that acts as an antibacterial agent is found in seagrass: Essential fatty acids, which can have antibacterial properties Symbiotic bacteria are microorganisms that live in mutualistic symbiosis with other organisms. The enzymatic activities of symbiotic bacteria can involve the production of enzymes that break down complex molecules into simpler molecules In food preservation, symbiotic bacteria, with their enzymatic activity, can be used as natural preservatives Using natural food preservatives derived from seagrass and mollusc symbiotic bacteria can contribute to a more sustainable and environmentally friendly approach to food preservation GRAPHICAL ABSTRACT