Screening Of Secondary Metabolites Research Articles

Combining culture optimization and synthetic biology to improve production and detection of secondary metabolites in Myxococcus xanthus: application to myxoprincomide.

Microbial secondary metabolites play crucial ecological roles in governing species interactions and contributing to their defense strategies. Their unique structures and potent bioactivities have been key in discovering antibiotics and anticancer drugs. Genome sequencing has undoubtedly revealed that myxobacteria constitute a huge reservoir of secondary metabolites as the well-known producers, actinomycetes. However, because most secondary metabolites are not produced in the laboratory context, the natural products from myxobacteria characterized to date represent only the tip of the iceberg. By combining the engineering of a dedicated Myxococcus xanthus DZ2 chassis strain with a two-step growth medium protocol, we provide a new approach called two-step Protocol for Resource Integration and Maximization-Biomolecules Overproduction and Optimal Screening Therapeutics (2PRIM-BOOST) for the production of non-ribosomal peptides synthetases (NRPS)/polyketides synthases (PKS) secondary metabolites from myxobacteria. We further show that the 2PRIM-BOOST strategy will facilitate the screening of secondary metabolites for biological activities of medical interest. As proof of concept, using a constitutive strong promoter, the myxoprincomide from M. xanthus DZ2 has been efficiently produced and its biosynthesis has been enhanced using the 2PRIM-BOOST approach, allowing the identification of new features of myxoprincomide. This strategy should allow the chances to produce and discover new NRPS, PKS, and mixed NRPS/PKS hybrid natural metabolites that are currently considered as cryptic and are the most represented in myxobacteria.IMPORTANCEMicrobial secondary metabolites are important in species interactions and are also a prolific source of drugs. Myxobacteria are ubiquitous soil-dwelling bacteria constituting a huge reservoir of secondary metabolites. However, because most of these molecules are not produced in the laboratory context, one can estimate that only one-tenth have been characterized to date. Here, we developed a new strategy called two-step Protocol for Resource Integration and Maximization-Biomolecules Overproduction and Optimal Screening Therapeutics (2PRIM-BOOST) that combines the engineering of a dedicated Myxococcus xanthus chassis strain together with growth medium optimization. By combining these strategies with the insertion of a constitutive promoter upstream the biosynthetic gene cluster (BGC), the production of myxoprincomide, a characterized low-produced secondary metabolite, was successfully and significantly increased. The 2PRIM-BOOST enriches the toolbox used to produce previously cryptic metabolites, unveil their ecological role, and provide new molecules of medical interest.

Antiproliferative Effects of Methanolic Fruit Extract of Solanum xenthocarpum (L.) on Human Breast Cancer Cells.

Solanum xanthocarpum, a perennial herb native to India, contains steroidal glycoalkaloids with notable anticancer properties. This study investigated the antioxidant and antiproliferative effects ofmethanolic fruit extract of S. xanthocarpum on human breast cancer cells (MDA-MB-231). Phytochemical screening and LC-HRMS analysis confirmedpresence of various primary and secondary metabolites. Antioxidant activity was assessed through DPPH, ABTS radical scavenging, reducing power, and phosphomolybdate assays. The extract demonstrated significant antioxidant potential with EC50 values of 60.10 ± 0.88 µg/mL (DPPH) and 392.29 ± 3.93 µg/mL (ABTS). Cytotoxicity against MDA-MB-231 cells was evaluated via morphological analysis, MTT assays, and IC50 determination (24.19 ± 0.56 µg/L). Apoptosis was confirmed using dual staining techniques (AO/EB, Hoechst 33342/PI, DAPI), revealing condensed nuclei, apoptotic bodies, and reduced mitochondrial membrane potential, as indicated by Rhodamine staining. Additionally, increased reactive oxygen species (ROS) levels were observed using H2-DCF-DA staining. The total phenolic and flavonoid contents of the extract were 127.78 ± 3.547 mg GAE/g and 98.06 ± 4.289 mg QE/g, respectively. These findings suggest that the methanolic fruit extract of S. xanthocarpum possesses strong antioxidant and anticancer activities, indicating its potential role in cancer treatment. Further studies are warranted to explore its bioactive compounds for developing novel anticancer therapies.

Screening of Extract Secondary Metabolites of Bacteria Which Have Symbiosis with Sponges from Central Tapanuli Bakar Island as an Antibacteria

This study aims to determine the presence of antibacterial-producing bacteria from sponges from Bakar Island, Central Tapanuli Regency and to determine the antibacterial activity of methanol extracts from potential bacterial isolates against Staphylococcus aureus and Escherichiacoli. 21 pure isolates were found and it was known that 9 isolates produced antibacterial against S. aureus and 4 isolates against E. coli. Bacterial isolates with the highest inhibition zone against bothS.aureus and E. coli were found in isolates with code SP20 with each large inhibition zone are 14.5 mm and 16.04 mm. Then microscopic observations were carried out, namely gram staining and were obtained 8 isolates were gram positive, and 1 gram was negative. The biochemical test showed that SP20 showed positive results for the Motility, TSIA and Catalase Test but negative for Citrate Test. Bacterial isolates withthe code SP20 had the largest inhibition zone so that these isolates were to be extracted.The resultsof the screening test showed that the secondary metabolitesof the sponge symbiont bacterial extract from Bakar Island were positive for flavonoids and saponins. And then test the activity of secondary metabolites with 3 concentrations, 10%, 20%, and 30%.The results showed that the best concentration of the test bacteria was S. aureus at a concentration of 30% with an inhibition zone of 3.08 mm and E. coli at 5.04 mm.

Isolation, Screening and Biocidal Activity of Secondary Metabolites from Fungi of Paddy Field Soil Samples in Selected Alanganallur Sub Regions, Madurai, Tamil Nadu

Isolation, Screening and Biocidal Activity of Secondary Metabolites from Fungi of Paddy Field Soil Samples in Selected Alanganallur Sub Regions, Madurai, Tamil Nadu

Phytochemical Screening and Antioxidant Activity of <i>Annona Senegalensis</i> Extracts (Leaves and Stem Bark) Collected from Three Regions of Senegal

The main objective of the present study is to focus on evaluation of the secondary metabolites composition and antioxidant activity of hydro – ethanolic extracts of <i>Annona senegalensis</i> leaves and stem bark which used in traditional medicine against several kind of diseases. The yields of hydro-ethanolic extracts of organs (leaves and Stem bark) were determined, followed by phytochemical screening and amount of secondary metabolites, by using conventional analytical methods. Anti-radical activity was carried out by DPPH (2, 2-diphenyl-l-picrylhydrazyl) reduction tests. The best extraction rates, whatever the plant organ or origin, were obtained with leaves (15.5% on average). Phytochemical screening revealed the presence of polyphenols, flavonoids and tannins. The highest levels of total polyphenols were obtained with leaves extracts [83.931 ± 0.018 g EGA/100 g Dry Matter (DM)] compared with stem bark (77.886 ± 1.001 g EGA/100 g DM). The highest tannin and flavonoid contents are 1.093 ± 0.006 g EC/100 g DM and 0.195 ± 0.004 g EC/100 g DM, respectively. Moreover, the extracts have a high antioxidant capacity with high inhibition percentages of 95.06 ± 0.10% for the leaves and 92.87 ± 0.10% for the bark. These results highlight the presence of bioactive compounds and potential antioxidant activity that have been shown to be efficient in the treatment of certain diseases, in accordance with ethno - botanical survey.

The potential of Chlorella spp. as antiviral source against African swine fever virus through a virtual screening pipeline

African swine fever (ASF) causes high mortality in pigs and threatens global swine production. There is still a lack of therapeutics available, with two vaccines under scrutiny and no approved small-molecule drugs. Eleven (11) viral proteins were used to identify potential antivirals in in silico screening of secondary metabolites (127) from Chlorella spp. The metabolites were screened for affinity and binding selectivity. High-scoring compounds were assessed through in silico ADMET (Absorption, Distribution, Metabolism, Excretion, Toxicity) predictions, compared to structurally similar drugs, and checked for off-target docking with prepared swine receptors. Molecular dynamics (MD) simulations determined binding stability while binding energy was measured in Molecular Mechanics - Generalized Born Surface Area (MMGBSA) or Poisson-Boltzmann Surface Area (MMPBSA). Only six (6) compounds passed until MD analyses, of which five (5) were stable after 100 ns of MD runs. Of these five compounds, only three had binding affinities that were comparable to or stronger than controls. Specifically, phytosterols 24,25-dihydrolanosterol and CID 4206521 that interact with the RNA capping enzyme (pNP868R), and ergosterol which bound to the Erv-like thioreductase (pB119L). The compounds identified in this study can be used as a theoretical basis for in vitro screening to develop potent antiviral drugs against ASFV.

Screening of Secondary Metabolites, Antibacterial and Antioxidative Capacity of Paederia Foetida L. Leaf Extracts

Plant resources have been utilized since ancient times for the healing of various illnesses of humankind. This study investigated the secondary metabolites, antibacterial, and antioxidative capability of Paederia foetida L. (P. foetida) leaf extract. Qualitative tests were done to determine the presence of secondary metabolites. The disc diffusion method was used for the determination of the antibacterial activity of the extract. The DPPH (1, 1-diphenyl-2-picrylhydrazyl) free radical scavenging assay, reducing power assay, total phenolic, and total flavonoid content methods were followed for the evaluation of antioxidative potentials of the leaf extract. The leaf extract was found to show significant (p < 0.05) antibacterial activity against Gram-positive bacteria compared to Gram-negative ones. In DPPH free radical scavenging assay, the inhibitory concentration (IC50) value for methanol crude extract was found to be fairly significant (162.929 μg/mL) in comparison with that (1.57 µg/mL) of the reference standard ascorbic acid. The maximum absorbance for reducing power assay was 0.823 compared to 1.891 for standard ascorbic acid. The extract was found to have a total phenolic content of 8.03 ±1. 05 mg/g gallic acid equivalent and flavonoid content 134.74 mg/g quercetin equivalent. The results demonstrated a moderate antibacterial and promising antioxidative activity of P. foetida leaf extract, but it is necessary to further analyze prospective pharmaceutical preparation. The Chittagong Univ. J. B. Sci.,Vol. 10(1 &2):121-137, 2020

Phytochemical screening, quantitative analysis and antioxidant properties of crude extracts from stems, leaves, and flowers of three Ruta species

In this work, the stems, leaves, and flowers of Ruta chalepensis L., R. graveolens L., and R. montana L. harvested in Morocco were subject to a comparative study to determine the phytochemical composition, antioxidant capacities, and the content of total phenols and flavonoids. For this purpose, 45 crude extracts (CEs) were prepared using different solvents, including water, ethyl acetate, methanol, ethanol, and hexane. Upon undergoing secondary metabolites screening, it was discovered that the different parts of three Ruta species contain a high level of secondary metabolites such as alkaloids, catechic tannins, flavonoids, coumarins, sterols, and triterpenes. This was confirmed by the results of the quantitative analysis, which proved that the three Ruta species contain a significant amount of total phenolic compounds, ranging from 27.05 to 213.42 mg GAE/g CE. With regard to antioxidant capacities, antiradical power (ARP) results prove that the majority of CEs have great ARP (were within the range of 0.42–1.99) compared to the BHT (butylated hydroxytoluene) standard (0.33 APR). In addition, the results of total antioxidant capacity (TAC) analysis of Ruta CEs showed good TAC (varies between 37.67 and 396.80 mg AAE/g CE).

Isolation, characterization, and screening of secondary metabolites from endophytic fungi isolated from Nigerian Piliostigma thonningii for antimicrobial activities

Piliostigma thonningii leaves are used in Nigeria folk medicine for the treatment and management of diverse ailments. This study was carried out to investigate the antimicrobial activity of the secondary metabolites produced from endophytic fungi isolated from the leaves of Piliostigma thonningii. The isolation of endophytic fungi was carried out according to the standard procedures. The fungi were subjected to solid-state fermentation on rice medium and the secondary metabolites extracted using ethyl acetate. The fungal crude extracts were screened for antimicrobial activity against selected clinically important microbes using the agar well diffusion method. The fungus with the best antimicrobial activity was molecularly characterized and its secondary metabolites profiled using Gas Chromatography - Mass Spectroscopy to establish the correlation between the observed activity and its phytochemical composition. The fungal extracts showed antimicrobial activity with inhibitory zone diameter ranging from 2.00 to 9.00 mm. The secondary metabolites of Aspergillus fumigatus (the most bioactive endophyte) contain 50 compounds with several of them having established antimicrobial activity. The results of this study suggest that Aspergillus fumigatus an endophytic fungus associated with P. thonningii could be a promising source of novel bioactive compounds with pharmaceutical, agricultural and industrial importance. Keywords: Antimicrobial, Endophytic fungi, GC-MS, Piliostigma thonningii

Efficacy of herbal extracts in the management of cactus pest, Dactylopius opuntiae (Hemiptera: Dactylopiidae) in Tigray Region, Ethiopia

Cactus (Opuntia ficus-indica) is a drought-resistant plant and the source of food and income for many farmers during the rainy season, and the only option to feed livestock during the dry seasons, especially in the southern part of the Tigray region of Ethiopia. The region is currently suffering from a damaging parasitoid of cactus called Dactylopius opuntiae- ficus biotype. An experimental study was conducted from August 2022 to February 2023 to investigate the efficacy of herbal extracts against cochineal insects. The experiment was conducted on the insecticidal property of methanol extracts of Solanum linnaenum, Euphorbia tirucalli, Nerium oleander, Tephrosia vogelii, Calpurnia aurea, Argemone Mexicana, Datura stramonium and Ricinus communis. Herbs were extracted, and their efficacy and LC50 were determined. Phytochemical screening for secondary metabolites was performed. There was a statistically significant difference in the mean mortality of insects across the levels of the herbs (F (8, 71) = 57.812, p = 0.0001, ƞ2 = 0.867) and the experimental extract concentrations (F (1, 71) = 4198.3, p = 0.0001, ƞ2 = 0.983). The individual extracts of S. linnaenum and N. oleander caused average mortality rates of 99.3% and 97.4%, respectively, at 5% extract concentration. Tannins and saponins were the major metabolites found in the extracts. The present study demonstrated the promising insecticidal efficacy of herbal extracts against the damaging cacti pest D. opuntia-ficus biotype, providing insights into sustainable pest control strategies for protecting vital cactus resources in the Tigray region.

Advancing Hemidesmus indicus propagation and conservation: Somatic embryogenesis, histology, metabolite assessment and genetic stability

Hemidesmus indicus L. R. Br. is a commonly traded ethnomedicinal plant, and a method has been developed to produce somatic embryos (SEs) from calli grown from the leaves of the plant. With a maximum callus induction frequency of 91.66 %, pink-red friable proembryogenic calli were generated on Murashige and Skoog (MS) and 5.0 µM 2, 4-dichlorophenoxyacetic acid (2, 4-D) from the leaf explant (LE). With the aim of achieving a high success rate of 95.00 % for the induction of SEs, with a yield of 91.33 SEs per 100 mg of callus, the proembryogenic calli were transferred to fresh culture medium containing MS and 5.0 µM 6-benzylaminopurine (BA). This induction medium allowed the embryos to develop to the torpedo stage, but their further growth into emblings required a different culture medium. ½ MS with 5.0 µM BA and 1.0 µM gibberellic acid (GA3) resulted in 99.16 % maturation and 39.66 emblings regeneration out of 40 immature embryoids, respectively. With a maximum survival rate of 91.67 %, healthy emblings were successfully acclimatized using Soilrite. DNA-based molecular markers (RAPD and ISSR) were used to confirm the genetic similarities of the in vitro grown plants. Histological examinations were performed to determine the ontogeny, morphology, and development of somatic embryoids. Gas chromatography and mass spectrometry (GCMS–) were performed for both the mother and the in vitro generated plant to analyse the root for secondary metabolites. In the physiological and biochemical studies, enzymes such as superoxide dismutase (SOD), ascorbate peroxidase (APX), catalase (CAT), and glutathione reductase (GR) were found to increase in vitro derived H. indicus plants during different acclimatization periods (0, 7, 14, 21 and 28 days). With increasing acclimatization time, net photosynthetic rate (PN) and total chlorophyll show a decrease at first, then an increase. The protocol provides high callus induction rates, efficient somatic embryogenesis, successful maturation and regeneration, robust acclimatization, genetic fidelity, detailed insight into development, and screening of secondary metabolites.

An exploratory in silico analysis of bacteriocin gene clusters in the urobiome

Background: The role of the urobiome in health and disease remains an understudied area compared to the rest of the human microbiome. Enhanced culturing techniques and next-generation sequencing technologies have identified the urobiome as an untapped source of potentially novel antimicrobials. The aim of this study was to screen the urobiome for genes encoding bacteriocin production. Methods: The genomes of 181 bacterial urobiome isolates were screened in silico for the presence of bacteriocin gene clusters using the bacteriocin mining tool BAGEL4 and secondary metabolite screening tool antiSMASH7. Results: From these isolates, an initial 263 areas of interest were identified, manually annotated, and evaluated for potential bacteriocin gene clusters. This resulted in 32 isolates containing 80 potential bacteriocin gene clusters, of which 72% were identified as class II, 13.75% as class III, 8.75% as class I, and 5% as unclassified bacteriocins. Conclusion: Overall, 53 novel variants were discovered, including nisin, gassericin, ubericin, and colicins.

Screening of Secondary Metabolites Produced by Nigrospora sphaerica Associated with the Invasive Weed Cenchrus ciliaris Reveals Two New Structurally Related Compounds.

In the search for new alternative biocontrol strategies, phytopathogenic fungi could represent a new frontier for weed management. In this respect, as part of our ongoing work aiming at using fungal pathogens as an alternative to common herbicides, the foliar pathogen Nigrospora sphaerica has been evaluated to control buffelgrass (Cenchrus ciliaris). In particular, in this work, the isolation and structural elucidation of two new biosynthetically related metabolites, named nigrosphaeritriol (3-(hydroxymethyl)-2-methylpentane-1,4-diol) and nigrosphaerilactol (3-(1-hydroxyethyl)-4-methyltetrahydrofuran-2-ol), from the phytotoxic culture filtrate extract were described, along with the identification of several known metabolites. Moreover, the absolute stereochemistry of (3R,4S,5S)-nigrosphaerilactone, previously reported as (3S,4R,5R)-4-hydroxymethyl-3,5-dimethyldihydro-2-furanone, was determined for the first time by X-ray diffraction analysis. Considering their structural relationship, the determination of the absolute stereochemistry of nigrosphaerilactone allowed us to hypothesize the absolute stereochemistry of nigrosphaeritriol and nigrosphaerilactol.

Mining Secondary Metabolites of Chassalia curviflora Leaves Using SIRIUS and High-Resolution Mass Spectrometry Data

Chassalia curviflora (Wall ex Kurz.) Thwaites is a flowering plant from Rubiaceae family. Previous phytochemical investigation on Chassalia species led to the isolation of benzoic acid, benzoquinone derivatives, flavonoids, monoterpenoid indole alkaloids and its essential oil composition. However, these are still scarce in terms of its scientific report on studied species. This study was carried out to investigate fast screening of secondary metabolites by using data-dependent acquisition (DDA) LC-MS/MS analysis of methanolic extract of the leaf of the C. curviflora in positive ionization mode. The data were analysed using computational mass spectrometry method from molecular structure database search implemented in Sirius. This led in discovering of 13 known secondary metabolites from a distinct tandem MS data. De novo molecular formula annotations and predictions from SIRIUS suggested five major class compounds classified as coumarin, benzofuran, fatty acids, esters and triterpenes. Stigmasterol 12 and β-sitosterol 13 were successfully isolated, thus used to verify the data obtained from the Sirius. With our results, we advocate the MS-based approach as a useful starting method for the dereplication of compounds from the complex crude extract of plants.

Anti-obesity activity of Erythrina subumbrans (Hassk.) Merr leaves extract in high fructose-induced obesity in Wistar rats

Introduction: Obesity is known to lead to the development of metabolic disorders and Erythrina subumbrans (Hassk.) Merr has shown the potential in alleviating some diseases. This study aimed to assess the anti-obesity activity of the ethanol extract of E. subumbrans leaves (EES) in obese Wistar albino rats. Methods: The rats were randomly assigned to eight groups (n = 5): normal group (no obesity inducement, treated with standard feed); high fructose (60%)-induced obesity (obesity induced, no treatment); control-1 group (obesity-induced, treated with orlistat 10.8 mg/kg BW); control-2 group (obesity-induced, treated with Isprinol 45 mg/kg); control-3 group (obesity-induced, treated with metformin 45 mg/kg); three test groups (obesity-induced, treated with EES 100, 200, and 400 mg/kg, respectively). The obesity inducement was conducted for 7 weeks. The rats were observed for body weight (BW), feed residue, feces index, triglycerides, organ index, and leucocyte profile. Results: The screening for secondary metabolites in EES revealed the presence of flavonoids, alkaloids, saponins, polyphenols, and tannins. EES decreased the percentage of BW gain, appetite, organ index (spleen), total fat, triglycerides, and leucocyte profile of the rats. Conclusion: The ethanol extract of the leaves of E. subumbrans has the potential to be developed as an anti-obesity agent, although the molecular mechanism of its pathway modulation is still unknown.

In silico studies on Epicoccum spp. Secondary metabolites as potential drugs for mucormycosis

Mucormycosis is a rare and severe form of fungal infection caused by some fungal species belonged to mucormycetes that mainly infects skin but also eyes and other organs of the human body. The COVID-19 pandemic has demonstrated the rise in mucormycosis cases due to usage of industrial grade oxygen and overuse of steroids particularly in developing nations, where the pandemic has stressed the medical system to its limit. The major aim of this study was to screen potential antifungal compounds produced by Epicoccum spp. against target enzyme lanosterol 1,4-alpha demethylase of Rhizopus arrhizus var. delemar (strain RA 99–880 / ATCC MYA-4621 / FGSC 9543 / NRRL 43880), to evaluate potential drug candidates using in silico approach, compounds that may be explored further for the treatment of mucormycosis. Sequence of enzyme was retrieved from the UniProtKB database and ligands from PubChem database. 3D structure was obtained using protein homology modelling (SWISS-MODEL server). The target enzyme was prepared along with ligands using ADT software and then subjected to molecular docking using Autodock Vina. The results and protein-target interactions were studied using the BIOVIA Discovery studio. After virtual screening of secondary metabolites produced by Epicoccum spp. and after comparing them with the results of control drugs, the compound curvularin specifically showed potential interactions with amino acid residues of target enzymes. It is also exclusively binding to the iron atom of the hemoglobin (HEME) group with binding affinity of −12.3 kcal/mol, where the hemoglobin is the main target of current existing drugs used for treating patients. The stability of molecular complexes can be measured through molecular dynamic simulation and root mean square fluctuation (RMSF) values. In this study, stable complexes were formed with curvularin and rostratin A having the highest RMSF values of 4.3 Å and 4.5 Å, respectively. Lower RMSF values indicate stability, while higher values indicate flexibility. The ADMET score gave an outlook about the absorption, distribution, metabolism, excretion and toxicity of the ligands. All the drug candidates used in this study passed the basic Lipinski rule of five except orevactaene. Curvularin and rostratin A were predicted as enzyme inhibitors by a bioactivity prediction tool (Molinspiration). In vitro and in vivo studies will be a way to go further.

Physical Characterization of Chitosan-based Syzygium polyanthum Leaves Extract Nanoparticles

Indonesia is one of the most abundant in natural resources countries in the world. The bay leaves are well- known among the locals and have various pharmacological properties, including anti dyslipidemia. Currently, the use of nanoparticle technologies in dyslipidemia treatment is quite popular. These treatments have numerous advantages such as enhancing the potency of dyslipidemia agents. The purpose of this study is to develop chitosan-based nanoparticles made from Syzygium polyanthum leaves extract using crosslink method. Chitosan is used as the polymer and STPP as the crosslinker with the ratio of chitosan:STPP is 5:1. Two formula is generated, F1 is chitosan-based nanoparticle extract and F2 is chitosan-base nanoparticle blank. Syzygium polyanthum extract contains alkaloid, flavonoid, saponin, quinone, and tannin, as determined by secondary metabolites screening. The total flavonoid content of Syzygium polyanthum leaves extract determined as quercetin is 0.04%. Physical properties of generated nanoparticles such as size, polydispersity index (PI) and zeta potential are investigated. Particle sizes of nanoparticles F1 and F2 are 180.1 ± 0.5 nm and 464.3 ± 25.98 nm with the PI values of F1 and F2 are 0.220 ± 0.02 and 0.563 ± 0.112 respectively. Zeta potential value for F1 is 21.8 ± 1.74 mV and F2 is 17.8 ± 0.21 mV. The entrapment efficiency is evaluated to determine the extract content of the nanoparticle, and the result is 47.13%. From this research, the chitosan-based nanoparticles containing Syzygium polyanthum formula have good physical properties. Further investigation is needed to evaluate its potential as anti-dyslipidemia.

Phytochemical Screening of Secondary Metabolites, Antioxidant and Antibacterial Activities of Kalangkala Plant (Litsea Angulata): A Review Article

Litsea angulata, more commonly known as Kalangkala, is a type of plant that belongs to the Lauraceae family. Empirically, the plant has been used traditionally by local people for the treatment of boils, diarrhea, stomachache, dyspepsia, gastroenteritis, diabetes, insect bites, and anti-irritation. This review article aims to find out the results of phytochemical screening of metabolites from parts of Kalangkala plant with various solvents as well as the results of the tests of antioxidant and antibacterial activities that several researchers have carried out. The method used was a literature search on Google Scholar and Pubmed with the keywords kalangkala, Litsea angulata, phytochemical screening, antioxidant, and antibacterial. The results of this review showed that various solvents, such as water, ethanol, methanol, N-hexane, and ethyl acetate in seed, fruit flesh, bark, stem, and leave parts of Kalangakala plant produces different amounts of secondary metabolites. Secondary metabolites such as alkaloids, flavonoids, saponins, and tannins extracted well using etanol as a solvent due to their polarity. The results of the antioxidant activity showed that the part of kalangakala plant such as the bark of the tree, has a very good antioxidant activity of 2.41 ppm when tested using ethyl acetate solvent. Furthermore, the results of the antibacterial activity test show an inhibition of 50 mm on S. mutans bacteria when tested using ethanol solvent. In conclusion, kalangkala plant has secondary metabolites which act as antioxidants and antimicrobials that also potential to developed as traditional medicine.

Antifungal Activity of Cassia fistula L. Extracts against Macrophomina phaseolina (TASSI.) Goid.: In vitro Study

Aim: To evaluate the anti-fungal properties of Cassia fistula with alcohol soluble and aqueous extracts against Macrophomina phaseolina.
 Methods: Ethanolic, methanolic and aqueous extracts were prepared and qualitative and quantitative analysis of phytoconstituents was done. The antioxidant and antifungal activity of the extracts were determined.
 Results: It was observed that the methanolic extract had the highest (15.65%) extraction yield, whereas ethanolic extract had the lowest (12.45%) extraction yield. While screening for secondary metabolites, cardiac glycosides were found to be lacking in all three solvent extracts, while sterols was absent in the aqueous extract. The methanolic extract contained the highest amounts of phenolic compounds (13.38±0.060 mg GAE/g dw.), flavonoid (10.58±0.074 mg QUE/g dw.), tannin (11.43±0.052 mg TAE/g dw.), and alkaloid (16.18±0.062 mg AE/g dw.). The highest antioxidant activity was observed in the methanolic extract at 300 µg/ml (% inhibition, 63.02%). Antifungal activity against M. phaseolina was also highest (68.07%) for the methanolic fraction.
 Conclusion: C. fistula extracts may be further be explored to formulate antifungal agents.

Actinomycetes and Fungi Isolated From Maliau Basin, Sabah and The Screening For Novel Secondary Metabolites Against Eukaryotic Signal Transduction and Mycobacterium

Maliau Basin is one of the world's hot spot of biodiversity.