Yield Of Secondary Metabolites Research Articles

Effects Of 2,4-D, BAP, and Sucrose Concentrations in The Callus Induction of White (Clitoria ternatea var. Albiflora) and Blue Butterfly Pea (Clitoria ternatea)

The blue butterfly pea (Clitoria ternatea) and white butterfly pea (Clitoria ternatea var. Albiflora) belong to the Fabaceae family. Both are locally known as “bunga telang” and native to the Southeast Asian regions. The blue flowered variety is traditionally used to treat headaches, fever, and diabetes and is renowned scientifically for its memory-enhancing properties due to the presence of novel pentacyclic triterpenoids. However, farming of C. ternatea is challenged by inconsistent yields of novel secondary metabolites, especially under changing environmental conditions. Callus and cell suspension cultures, on the other hand, offer an alternative for the consistent production of these metabolites. The current study aims to optimize the treatments of 2,4-dichlorophenoxyacetic acid (2,4-D), 6-benzylaminopurine (BAP), and sucrose concentrations for friable callus formation from seedling explants. Sterile cotyledon explants of in vitro seedlings from both types of butterfly pea were subjected to half-strength MS medium supplemented with different concentrations and combinations of 2,4-D and BAP, with sucrose at 15 g/L and 30 g/L. The highest friable callus fresh weight from the white butterfly pea explants (0.064 ± 0.010 g) was achieved in treatments of 0.40 mg/L 2,4-D and 0.50 mg/L BAP. In contrast, the highest fresh weight of friable callus for the blue variety (0.025 ± 0.016 g) was induced in 0.25 mg/L of 2,4-D. Both varieties showed the highest friable callus weight in 15 g/L sucrose supplemented with 1.00 mg/L of 2,4-D (0.146 ± 0.032 g) and 0.25 mg/L of 2,4-D (0.245 ± 0.075 g) for the white and blue variety respectively. The morphology of calli for both varieties were yellowish, watery, and sticky. This study provides an essential basis the establishment of cell suspension cultures, as an efficient alternative to harness the secondary metabolites associated with the mammalian neuroprotective properties.

Exogenously Applied Gibberellic Acid Alters Cannabinoid Profile in Cannabis sativa L.

Cannabis sativa (C. sativa L.) has garnered significant attention worldwide due to its widespread use as a pharmaceutical agent. With the increasing clinical application of C. sativa and cannabinoid therapeutics, there is strong interest in the development of superior plant varieties and optimisation of growth conditions to enhance secondary metabolite yield. Our RNA sequencing analysis revealed differential expression of hormone-related transcripts in developing C. sativa trichomes, suggesting the involvement of hormone signalling pathways in cannabinoid production. Leveraging the potency of exogenous hormones on plants, this study sought to determine if the application of cytokinin (CK), gibberellic acid (GA) and jasmonic acid (JA) modified trichome morphology and the cannabinoid profile over an 8-week period following the induction of flowering. Exogenous hormone application led to alterations in trichome morphology, with each treatment significantly reducing trichome head width by the final week of assessment. Interestingly, GA application also resulted in a significant reduction in the concentration of Δ-9-tetrahydrocannabinol (THC), Δ-9-tetrahydrocannabinolic acid (THCA), cannabidiol (CBD) and cannabidiolic acid (CBDA) by week 8 post floral induction, however, JA and CK treatment did not consistently modulate the accumulation of these cannabinoids. The minor cannabinoids, cannabidivaranic acid (CBDVA), cannabicyclolic acid (CBLA), cannabicyclol (CBL), cannabichromene (CBC), cannabigerolic acid (CBGA) and cannabigerol (CBG), were also affected by hormone treatments, with varying degrees of accumulation observed. These findings underscore the intricate interplay between phytohormones and secondary metabolite biosynthesis in C. sativa. Our study highlights the potential of hormone modulation as a strategy to enhance cannabinoid yield and offers some insights into the regulatory mechanisms governing cannabinoid biosynthesis in C. sativa trichomes.

Variations in photoperiods and their impact on yield, photosynthesis and secondary metabolite production in basil microgreens

BackgroundThe effects of different photoperiods on plant phytochemical synthesis can be improved by adjusting the daily light integral. Photoperiod is one of the most important environmental factors that control growth, plant’s internal rhythm and the synthesis of secondary metabolites. Information about the appropriate standard in terms of photoperiod for growing basil microgreens as one of the most important medicinal plants is limited. In this study, the effects of five different photoperiods, 6 (6 h × 3 cycles), 8 (8 h × 2 cycles), 16, 18, and 24 h day− 1 on the yield, photosynthesis and synthesis of secondary metabolites of three cultivars and one genotype of basil microgreens in floating system were evaluated. The purpose of this research was to determine the feasibility of using permanent light in growing basil microgreens and to create the best balance between beneficial secondary metabolites and performance.ResultsThe results showed that the effects of photoperiod and cultivar on all investigated traits and their interaction on photosynthetic pigments, antioxidant capacity, total phenolic compounds, proline content and net photosynthesis rate were significantly different at the 1% level. The highest levels of vitamin C, flavonoids, anthocyanins, yield and antioxidant potential composite index (APCI) were obtained under the 24-h photoperiod. The highest antioxidant capacity was obtained for the Kapoor cultivar, and the highest total phenolic compound and proline contents were measured for the Ablagh genotype under a 24-h photoperiod. The highest yield (4.36 kg m− 2) and APCI (70.44) were obtained for the Ablagh genotype. The highest nitrate content was obtained with a photoperiod of 18 h for the Kapoor cultivar. The highest net photosynthesis rate was related to the Violeto cultivar under a 24-hour photoperiod (7.89 μmol CO2 m− 2 s− 1). Antioxidant capacity and flavonoids had a positive correlation with phenolic compounds and vitamin C. Yield had a positive correlation with antioxidant capacity, flavonoids, vitamin C, APCI, and proline.ConclusionsUnder continuous light conditions, basil microgreens resistance to light stress by increasing the synthesis of secondary metabolites and the increase of these biochemical compounds made basil microgreens increase their performance along with the increase of these health-promoting compounds. The best balance between antioxidant compounds and performance was achieved in continuous red + blue light. Based on these results, the use of continuous artificial LED lighting, due to the increase in plant biochemical with antioxidant properties and yield, can be a suitable strategy for growing basil microgreens in floating systems.

Profiling Bioactive Compounds in the Bark of Cinchona officinalis L. and Anti-arthritic Properties Thereof

The bark samples of C. officinalis were collected from The Nilgiris district of Tamil Nadu. The collected samples were processed and extracted using methanol solvent. The extracts showed high yield of secondary metabolites especially alkaloids, phenols, flavonoids, steroids, terpenoids, sterols, quinones and tannins. Alkaloid content was very high in C.officinalis followed by phenol, flavonoid, steroid and Tannin. The secondary metabolites present in C. officinalis (Bark) were isolated, purified, identified and characterized using differential Chromatographic techniques such as TLC, HPLC and GC-MS/ MS. The compounds identified using High Performance Liquid Chromatography (HPLC) technique in bark of C. officinalis in the retention times of 1.750, 2.250, 4.016 and 7.266 minutes were quinine, isoquinidine and cinchonidine. The compounds were then characterized using GC- MS/ MS technique with reference to NIST library. The compounds were eluted from the bark of C. officinalis in the retention time of 9.569, 10.488, 11.814, 13.593, 14.282, 16.542, 16.967, 23.494, 24.954, 25.151, 25.988, 26.752, 26.982, 27.906, 28.277, 31.454, 33.604, and 35.744 minutes. By correlating the retention times with (NIST) mass spectral library the eluted compounds were confirmed as Phthalic acid, Hexadecanoic acid,1,2,3,5-Cyclohexanetetrol, Cinchonab-9-one, 9,12-Octadecadienoic acid (Z,Z)-, Heptadecanoic acid, Quinine, Cinchonine, Cinchonidine, Phenol, Quinine, and gamma.-Sitosterol. The phytochemicals present in the C. officinalis (Bark) samples were evaluated for their biological properties viz., anti-inflammatory activity and anti-arthritic activity in in-vitro conditions. Anti- inflammatory properties of plant samples were tested by protein denaturation method using diclofenac (75 mg/ ml concentration) as positive control. The methanol extract of C.officinalis (Bark) showed anti- inflammatory properties of range between 17.0 and 57.3%. Anti- arthritic activity of bark extract of C. officinalis (75 mg/ ml concentration) was evaluated by albumin denaturation method using diclofenac (75 mg/ ml concentration) as positive control. The methanol extract of C.officinalis (Bark) showed anti- arthritic properties of range between 18.4 and 58.5%. From the study it is understood that the alkaloids and polyphenols present in the methanolic extract of bark of C. officinalis were responsible for their biological properties. Hence, C. officinalis can serve as an alternative to synthetic drugs available in the market to treat arthritis subject to safety (toxicity) studies in humans. Based on the In vitro results, it was confirmed that the bark of C.officinalis possesses comparatively high biological values. Thus an herbal aerosol for arthritis may be formulated using the bark extract of C.officinalis as key ingredient and the therapeutic product will be of cost effective, easy to use and pocket friendly.

An update on biotechnological intervention mediated by plant tissue culture to boost secondary metabolite production in medicinal and aromatic plants

AbstractSince prehistoric times, medicinal and aromatic plants (MAPs) have been employed for various therapeutic purposes due to their varied array of pharmaceutically relevant bioactive compounds, i.e. secondary metabolites. However, when secondary metabolites are isolated directly from MAPs, there is occasionally very poor yield and limited synthesis of secondary metabolites from particular tissues and certain developmental stages. Moreover, many MAPs species are in danger of extinction, especially those used in pharmaceuticals, as their natural populations are under pressure from overharvesting due to the excess demand for plant‐based herbal remedies. The extensive use of these metabolites in a number of industrial and pharmaceutical industries has prompted a call for more research into increasing the output via optimization of large‐scale production using plant tissue culture techniques. The potential of plant cells as sources of secondary metabolites can be exploited through a combination of product recovery technology research, targeted metabolite production, and in vitro culture establishment. The plant tissue culture approach provides low‐cost, sustainable, continuous, and viable secondary metabolite production that is not affected by geographic or climatic factors. This study covers recent advancements in the induction of medicinally relevant metabolites, as well as the conservation and propagation of plants by advanced tissue culture technologies.

Improvement of Bioactive Polyphenol Accumulation in Callus of Salvia atropatana Bunge.

Callus cultures of the Iranian medicinal plant Salvia atropatana were initiated from three-week-old seedlings on Murashige and Skoog (MS) medium supplemented with α-naphthaleneacetic acid (NAA) and various cytokinins. Although all tested hormonal variants of the medium and explant enabled callus induction, the most promising growth was noted for N-(2-chloro-4-pyridyl)-N'-phenylurea (CPPU)-induced calli. Three lines obtained on this medium (cotyledon line-CL, hypocotyl line-HL, and root line-RL) were preselected for further studies. Phenolic compounds in the callus tissues were identified using UPLC-MS (ultra-performance liquid chromatography-mass spectrometry) and quantified with HPLC (high-performance liquid chromatography). All lines exhibited intensive growth and contained twelve phenolic acid derivatives, with rosmarinic acid predominating. The cotyledon-derived callus line displayed the highest growth index values and polyphenol content; this was exposed to different light-emitting diodes (LED) for improving biomass accumulation and secondary metabolite yield. Under LED treatments, all callus lines exhibited enhanced RA and total phenolic content compared to fluorescent light, with the highest levels observed for white (48.5-50.2 mg/g dry weight) and blue (51.4-53.9 mg/g dry weight) LEDs. The selected callus demonstrated strong antioxidant potential in vitro based on the 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS), 2,2-diphenyl-1-picrylhydrazyl (DPPH), and ferric reducing antioxidant power (FRAP) tests. Our findings confirm that the S. atropatana callus system is suitable for enhanced rosmarinic acid production; the selected optimized culture provide high-quality plant-derived products.

Short-term salicylic acid application induces the expression of GPPS and NEPS1 in catnip

The catnip plant, Nepeta cataria L., produces bioactive iridoid monoterpenes known as nepetalactones. These monoterpenes follow a noncanonical biosynthetic route starting as isoprene monomers in the methylerythritol (MEP) pathway after condensation via geranyl pyrophosphate synthase (GPPS) and later cyclization through the iridoid pathway via nepetalactol-related short-chain dehydrogenase enzymes (NEPS). Nepetalactones exhibit insect repellant properties against disease-carrying vectors such as mosquitoes, bed bugs and ticks. Chemical elicitors such as salicylic acid have been used to induce biochemical changes in medicinal and aromatic plant species including catnip that can temporarily increase the yield and quality of secondary metabolites. This is the first study to correlate the effects of short-term salicylic acid application on the genes in the nepetalactone biosynthetic pathway. Both 0.5 mM SA and 1.0 mM SA resulted in upregulation of GPPS and NEPS1. However, within the 24-h time course of the study significant changes in nepetalactone yield were not observed. Correlation analysis revealed a significant relationship between the mRNA transcript abundance for GPPS and NEPS1 demonstrating a low positive co-expression strength for the two genes.

Effects of appropriate low-temperature treatment on the yield and quality of pigmented potato (Solanum tuberosum L.) tubers

Temperature is one of the important environmental factors affecting plant growth, yield and quality. Moreover, appropriately low temperature is also beneficial for tuber coloration. The red potato variety Jianchuanhong, whose tuber color is susceptible to temperature, and the purple potato variety Huaxinyangyu, whose tuber color is stable, were used as experimental materials and subjected to 20 °C (control check), 15 °C and 10 °C treatments during the whole growth period. The effects of temperature treatment on the phenotype, the expression levels of structural genes related to anthocyanins and the correlations of each indicator were analyzed. The results showed that treatment at 10 °C significantly inhibited the potato plant height, and the chlorophyll content and photosynthetic parameters in the leaves were reduced, and the enzyme activities of SOD and POD were significantly increased, all indicating that the leaves were damaged. Treatment at 10 °C also affected the tuberization of Huaxinyangyu and reduced the tuberization and coloring of Jianchuanhong, while treatment at 15 °C significantly increased the stem diameter, root-to-shoot ratio, yield and content of secondary metabolites, especially anthocyanins. Similarly, the expression of structural genes were enhanced in two pigmented potatoes under low-temperature treatment conditions. In short, proper low temperature can not only increase yield but also enhance secondary metabolites production. Previous studies have not focused on the effects of appropriate low-temperature treatment during the whole growth period of potato on the changes in metabolites during tuber growth and development, these results can provide a theoretical basis and technical guidance for the selection of pigmented potatoes with better nutritional quality planting environment and the formulation of cultivation measures.

Effect of Different Light Qualities on Essential Oil and Asarinin in Asarum heterotropoides Fr. Schmidt var. mandshuricum (Maxim.) Kitag

Asarum heterotropoides Fr. var. mandshuricum (Maxim.) is a perennial herb native to China. Its essential oil components and asarinin are health-promoting compounds. However, cultivation under natural light can affect the growth and secondary metabolite yield of this sciophyte. Adjustment of light irradiance may be beneficial in this respect. Here, we applied six types of filtered solar irradiance by using filter films of red (I), yellow (II), blue (III), green (IV), purple (V) and 50% sunlight (VI). We measured net photosynthetic rate (APn), activity of phenylpropanoid biosynthetic enzymes, asarinin content, and essential oil content and composition. Light quality treatments V and VI resulted in increased APn, enzyme activities, asarinin content and essential oil content. Samples harvested in September 2020 had relatively higher contents and enzyme activities compared to those harvested in July 2020. Elemicin, 2,5-dimethoxytoluene and methyleugenol accumulated at higher levels in response to light quality V. Light qualities III and IV showed promising results for several compounds. Overall, we conclude that controlling the light conditions in growing environments promotes the amount of asarinin and essential oil by regulating photosynthesis and the activities of phenylpropanoid biosynthetic enzymes.

COMPARATIVE CHROMATOGRAPHIC AND SPECTRAL STUDY OF THE ALKALOID COMPOSITION OF THE BIOMASS OF TISSUE CULTURE AND THE HERB OF GLAUCIUM FLAVUM

Introduction. The culture of plant cells and tissues is an effective technology for obtaining various secondary metabolites, including for use in the pharmaceutical industry. Compounds synthesized in callus and suspension cultures may be identical to plant ones, and the yield of secondary metabolites, in some cases, exceeds plant sources. In this regard, yellow hornpoppy (Glaucium flavum Crantz.) is of great interest, containing glaucin, which has a unique antitussive effect and is a source of a number of medications. The purpose of this study is a comparative phytochemical study of the alkaloid composition of the tissue culture and the herb of Glaucium flavum. Material and methods. Callus tissue cultures of yellow hornpoppy yellow hornpoppy (Glaucium flavum Crantz.) were obtained in the laboratory of the Institute of Pharmacy of Kazan State Medical University. The herb of the Glaucium flavum cultivated on the territory of the Botanical Garden of Samara University was collected during the flowering period of plants in 2021. A comparative study of the alkaloid composition of the callus culture and the herb of Glaucium flavum was carried out by methods of luminescent microscopy on an Altami LUM-2 microscope (Russia), thin-layer chromatography (TLC) on Sorbfil-PTSH-AF-A-UV plates, as well as spectrophotometry. A mixture of solvents n-butanol-acetic acid-water 4:1:2 was used as a solvent system. The detection of separated substances was carried out by scanning chromatographic plates in UV light at a wavelength of 366 and 254 nm, followed by the manifestation of Dragendorf reagent. The identification of the isolated glaucin hydrochloride was carried out on the basis of UV, 1H-NMR, 13C-NMR spectroscopy data. 1H NMR spectra were obtained on the "JNM-ECX 400" device (399.78MHz), 13C NMR spectra were obtained on the "JNM–ECX 400" device (100.52 MHz). The spectra were recorded using a Specord 40 spectrophotometer (Analytik Jena AG, Germany) in the wavelength range of 190-500 nm. Results. During the luminescent analysis of the tissue culture of the Glaucium flavum Crantz., as well as intact plants, the type of luminescence characteristic of isoquinoline alkaloids was noted. Using TLC analysis, isoquinoline alkaloids, including glaucin, were found in samples of callus cultures and the aerial parts of Glaucium flavum, however, a lower glaucin content was noted in the sample of the callus culture compared to that of the intact plant. The spectrophometric analysis of the studied samples showed that the nature of the absorption curve in intact plants and crops of the so-called Glaucium flavum has both common and distinctive features. The UV spectrum of water-alcohol extraction from a sample of Glaucium flavum tissue culture has a similar spectrophotometric profile, however, it contains only one absorption maximum (288 nm), coinciding with that of the UV spectrum of water-alcohol extraction from the herb of this plant. Conclusions. Therefore, the final conclusion regarding the content of glaucin in the studied samples can be made only during the preparative isolation of substances from the biomass of Glaucium flavum using column chromatography

Transcriptional Analysis of Antrodin C Synthesis in Taiwanofungus camphoratus (Syn. Antrodia camphorate, Antrodia cinnamomea) to Understand Its Biosynthetic Mechanism

Antrodin C, a bioactive component of Taiwanofungus camphoratus, exhibits good immunophysiological and antitumour activities, including a broad spectrum of anticancer effects. Exogenous additives can bind to metabolites during the submerged culture of T. camphoratus and affect secondary metabolite yields. However, the lack of molecular genetic studies on T. camphoratus has hindered the study of the antrodin C biosynthetic pathway. In this study, we conducted a ribonucleic acid-sequencing-based transcriptional analysis to identify the differentially expressed genes involved in the synthesis of antrodin C by T. camphoratus, using inositol and maleic acid (MAC) as exogenous additives. The addition of inositol significantly upregulated carbohydrate and sugar metabolism pathway genes (E3.2.1.14, UGDH, and IVD). When MAC was used, amino and nucleotide sugar metabolism and starch and sucrose metabolism pathways were significantly inhibited, and the associated genes (E3.2.1.14 and E3.2.1.58) were also significantly downregulated. The biosynthesis pathway genes for ubiquinone and other terpene quinones (COQ2, ARO8, and wrbA), which may play an important role in antrodin C synthesis, were significantly downregulated. This study advances our understanding of how the additives inositol and MAC affect metabolite biosynthesis in T. camphorates. This could be beneficial in proposing potential strategies for improving antrodin C production using a genetic approach.

Effect of Pruning Treatment on Growth Characteristics and Metabolites in Eucommia ulmoides Oliver (E. ulmoides)

The effect of pruning treatments on growth, photosynthesis characteristics, and metabolites were was studied in Eucommia ulmoides Oliver (E. ulmoides). The experiment was carried out from March–August 2019. Three treatments were used: non-pruned trees (CK), a height of 20 cm above the top edge of the flowerpot (T1), and a height of 10 cm above the top edge of the flowerpot (T2). The results showed that the branches branch number, leaves leaf number, and stem diameter increased significantly (p < 0.05) in pruning treatments compared with CK. Similarly, the net photosynthetic rate (Pn), stomatal conductance (Gs), transpiration rate (Tr), maximum photosynthetic efficiency (Fv/Fm), and non-photochemical quenching coefficient (NPQ) increased significantly in pruning treatments (p < 0.05). Interestingly, the contents of Chl a, Chl b, Chl, Car, and the rate between the Chl a content and the Chl b content increased significantly (p < 0.05) in T2, respectively. These verified that it was a better way to enhance the plants growth of E. ulmoides for pruning treatments. The GC-MS analysis showed that 36 different primary metabolites were identified, including 11 sugars, 13 acids, 5 alcohols, and 7 other compounds, the relative content of their metabolites were was higher in the T2 treatment than that in the T1 treatment, which was mainly concentrated in four main enrichment pathways (Galactose metabolism; Citrate cycle; Glyoxylate and dicarboxylate metabolism; and starch and sucrose metabolism) via KEGG analysis. Meanwhile, correlation analysis showed there were was a positive correlation between the accumulation of D-Galactose, D-Mannose, Succinic acid, and photosynthetic pigment content, and the rate of photosynthesis in T2 treatment (p < 0.05). The pruning height above the top edge of the flowerpot changed the accumulation of primary metabolites and promoted plant regeneration ability in E. ulmoides. Finally, the yield of main secondary metabolites from leaves (Genipin, Geniposide, Geniposidic acid, and Pinoresinol diglucoside) were was increased in pruning treatments by UPLC analysis. It provided a reference for the directional ecological cultivation of E. ulmoides.

BIOACTIVE METABOLITE PRODUCTION BY NOCARDIOPSIS SYNNEMATAFORMANSVLS-10 OF MANGROVE ORIGIN

Objective: Antibiotic resistance of pathogens has become a serious problem all over the world. Therefore, focusing for novel antibiotics is an important endeavor which is very much needed. Around 50 morphologically different Actinobacteria isolated from mangrove habitats of Krishna district, Andhra Pradesh, India were screened for antimicrobial activity. Methods: Among 50 isolates, one strain Nocardiopsis synnemataformans VLS-10 was identified based on morphological, physiological, biochemical, and molecular approaches. The effect of environmental parameters such as incubation period, pH, temperature and salt concentration, and effect of various nutrients such as carbon and nitrogen sources and minerals on the bioactive metabolite production by N. synnemataformans VLS-10 was evaluated by employing agar well diffusion assay. Results: Among the 50 isolates, one strain designated as VLS-10 was efficient to produce potential secondary metabolites. It was identified as N. synnemataformans based on polyphasic taxonomy. The present work is mainly aimed to study process optimization parameters to get high yield of bioactive compounds. ISP-2 medium supplemented with sodium chloride @ 9% maintained at pH 7.0 supported maximum yield of secondary metabolites by the strain when incubated at 35°C for 9 days. Conclusion: Secondary metabolites possessed broad-spectrum activity against human pathogenic bacteria and fungi. Hence, strain N. synnemataformansVLS-10 becomes a significant source for antimicrobial compounds.

Determination of Marker Compounds of Senna alata from different location in East Kalimantan, Indonesia

Senna alata is a plant used for medical purposes, and its leaves have an extended history of use as a traditional herbal medicine in Indonesia. S. alata is known to contain some components of biologically active compounds and also secondary metabolites. In fact, S. alata can grow well in various locations in Indonesia, location differences can lead to differences in compound content due to differences in environmental conditions such as soil, rainfall, light intensity, and humidity. Therefore, this study aimed to analyze marker compounds of S. alata plants origin from three different location in East Kalimantan, i.e Samarinda, Samboja, and Berau. This research was conducted to estimate the compounds contained in extracts by using GC-MS analysis, and to discover relationships between different variables by using Principal Component Analysis (PCA). There are variances in the yield of secondary metabolites according on where Senna alata is grown, specifically in the riverside Nyapa Indah region and the plains of Samarinda and Samboja. Based on GC-MS test results, Phytol was the main compound in S.alata in two areas, i.e. Samarinda and Samboja. Meanwhile, in Berau showed that 1,2-Benzenedicarboxylic acid, and mono (2-ethylhexyl) ester were the main components. However, S. alata leaf extracts could be used as a good quality raw material for pharmaceutical industries, such as a laxative agent.

OPTIMIZATION OF PROCESS PARAMETERS FOR IMPROVED PRODUCTION OF ANTIMICROBIAL METABOLITES FROM NOCARDIOPSIS FLAVESCENS VJMS-18 ISOLATED FROM SOUTH-COASTAL REGIONS OF ANDHRA PRADESH, INDIA

Objective: The objective of the present study is to optimize the cultural parameters for Nocardiopsis flavescens VJMS-18 strain isolated from marine sediment samples of the south-coast of Andhra Pradesh, India. Methods: The strain N. flavescensVJMS-18 was identified based on morphological, physiological, biochemical and molecular approaches. The effect of environmental parameters such as incubation period, pH, temperature and salt concentration and the effect of various nutrients such as carbon and nitrogen sources and minerals on the bioactive metabolite production by N. flavescens VJMS-18 was evaluated by employing agar well diffusion assay. Results: The nutritional requirements and cultural conditions to enhance the yield of secondary metabolites are optimized under shake flask conditions. ISP-2 medium supplemented with sodium chloride at 3% maintained at pH 7.0 supported the maximum yield of secondary metabolites by the strain when incubated at 35°C for 8 days. The strain exhibited a broad spectrum of antagonistic activity against Gram-positive (Staphylococcus aureus and Bacillus megaterium) and Gram-negative bacteria (Klebsiella pneumoniae, Escherichia coli and Pseudomonas aeruginosa) as well as fungus (Candida albicans). Conclusion: It was found that the antimicrobial metabolite production by the strain was positively influenced by carbohydrates, nitrogen sources and minerals.

Rhizobacterial mediated interactions in Curcuma longa for plant growth and enhanced crop productivity: a systematic review.

Turmeric (Curcuma longa L.), a significant commercial crop of the Indian subcontinent is widely used as a condiment, natural dye, and as a cure for different ailments. Various bioactive compounds such as turmerones and curcuminoids have been isolated from C. longa that have shown remarkable medicinal activity against various ailments. However, reduced soil fertility, climatic variations, rapid urbanization, and enhanced food demand, pose a multifaceted challenge to the current agricultural practices of C. longa. Plant growth-promoting microbes play a vital role in plant growth and development by regulating primary and secondary metabolite production. Rhizospheric associations are complex species-specific interconnections of different microbiota with a plant that sustain soil health and promote plant growth through nutrient acquisition, nitrogen fixation, phosphate availability, phytohormone production, and antimicrobial activities. An elaborative study of microbiota associated with the roots of C. longa is essential for rhizospheric engineering as there is a huge potential to develop novel products based on microbial consortium formulations and elicitors to improve plant health, stress tolerance, and the production of secondary metabolites such as curcumin. Primarily, the purpose of this review is to implicate the rhizospheric microbial flora as probiotics influencing overall C. longa health, development, and survival for an increase in biomass, enhanced yield of secondary metabolites, and sustainable crop production.

PHYTOCHEMICALS SCREENING AND ANTIOXIDANT ACTIVITY TEST OF ETHANOLIC EXTRACT OF CHINESE BETEL LEAVES (Peperomia pellucida L.) AND ITS FRACTIONS

Peperomia pellucida (Chinese betel) is considered as a plant with antioxidant activity for inhibiting oxidation reactions. This study aims to determine the yield of secondary metabolites, total flavonoid levels, and antioxidant activity. Dried leaves of Chinese betel were macerated using 70% ethanol as solvent. The extract was partitioned until the n-hexane and ethyl acetate fractions were obtained. A phytochemical screening test was followed by determining total flavonoid levels and antioxidant activity using UV-Vis spectrophotometry. Phytochemical screening results containing an ethanolic extract of Chinese betel leaves (ECBL) showed positive results on alkaloid, flavonoid, saponin, and tannin. Meanwhile, the ethyl acetate (EAF) and n-hexane (HF) fractions showed positive results only for flavonoid presence. The total flavonoid contents of ECBL, EAF, and HF were 3.30%, 2.54%, and 2.03%, respectively. The IC50 values of ECBL, EAF, and HF were 7.51 ppm, 8.02 ppm, and 8.04 ppm, respectively. The highest flavonoid content was found in ECBL. Antioxidant activity test of Peperomia pellucida ethanolic extract, ethyl acetate fraction, and n-hexane fraction showed potent antioxidant activity. Keywords: Antioxidant, Peperomia pellucida , DPPH

Biochar Application: A Viable and Pyrolysis Temperature Dependent Option for Enhancing Leaf Secondary Metabolites of Cyclocarya paliurus

While numerous studies have suggested that pyrolysis of the forestry residues to produce biochar and return it back for forestry use is an effective way for the utilization of forestry wastes, there have been few reports addressing the effect of pyrolysis temperature on its agronomic functions, especially the secondary metabolism of the medicinal tree. In this study, two kinds of biochar were pyrolyzed using poplar sawdust at 350 °C (C350) and 600 °C (C600), respectively, then applied as auxiliary substrate material for the cultivation of Cyclocarya paliurus seedlings in a greenhouse to study their effects on soil properties, seedling growth and the accumulation of main secondary metabolites in C. paliurus leaves. The results showed that biochar application definitely ameliorated most of the soil properties, and this improvement was further enhanced as the pyrolysis temperature of the biochar increased. Compared with the basic substrate (CK), the growth of C. paliurus seedlings increased under C600 and decreased under C350, but the application of two biochars had no significant effect on the content of the main secondary metabolites in the leaves. In contrast, the seedling growth with the direct application of poplar sawdust (C0) was significantly inhibited, while the content of secondary metabolites in the leaves increased significantly. In terms of the yield of leaf secondary metabolites, the application of biochar with high pyrolysis temperature (C600) had the highest yield, while the direct application of poplar sawdust had the lowest yield. In addition, the contents of several metabolite monomers were higher under C0 than these of the other three treatments. The results indicated a certain trade-off between the primary growth and the synthesis of leaf secondary metabolites in C. paliurus affected by different biochars and poplar sawdust application, while the accumulation of leaf secondary metabolites was generally dependent on leaf biomass.

Secondary metabolites of rhizospheric fungal isolate Aspergillus carneus ABRF4 regulate the antibacterial and anti-proliferative activity against cancer cells

Abstract. Sahu MK, Yeeravalli R, Das A, Jha H. 2023. Secondary metabolites of rhizospheric fungal isolate Aspergillus carneus ABRF4 regulate the antibacterial and anti-proliferative activity against cancer cells. Nusantara Bioscience 15: 137-142. The medicinal capabilities of plants are influenced by soil chemistry, genotype, and climate. Many biotic and abiotic factors affect soil composition. Microorganisms constituting the soil microflora indicate a mutualistic relationship with plant rhizospheric region, and they play an important role in plant secondary metabolite production, yield, and efficacy. They are the major resources for structurally unique bioactive natural metabolites. The aim of the present study was to evaluate the bioactivity of the secondary metabolite extracted from the rhizospheric fungal isolate Aspergillus carneus ABRF4) isolated from the Achanakmar Biosphere Reserve, Chhattisgarh, India. The fungal secondary metabolites were extracted using several solvents by soxhlet extraction techniques. The crude and partially purified column fractions of A. carneus ABRF4 were characterized by Gas Chromatography-Mass Spectroscopy (GC-MS), Fourier Transform Infra-Red (FTIR) spectrum, and Thin Layer Chromatography (TLC). Results showed that the acetonitrile fraction had an antimicrobial activity with the variable zone of inhibition against human pathogens such as Bacillus circulans (MTCC-7906), Bacillus subtilis (MTCC 441), Staphylococcus aureus (MTCC-96), and Ralstonia eutropha (MTCC-2487). The crude extracts and the identified secondary metabolite, trans- 1,3-dimethyl-Cyclohexane, possess different anti-proliferative activity against human tissue-specific cancer cell lines, including breast cancer (MDA-MB-231, MDA-MB-468, and MCF-7), liver cancer (HepG2), lung cancer (A-549), and prostate cancer (DU-145) suggesting a potential therapeutic application of the isolated rhizospheric fungi.

Isolation of two new stereochemical variants of streptophenazine by cocultivation of Streptomyces NIIST-D31, Streptomyces NIIST-D47, and Streptomyces NIIST-D63 strains in 3C2 combinations.

Cocultivation of combinations of Streptomyces species isolated from the same soil was explored to isolate novel secondary metabolites. Recently, we reported the isolation of a novel vicinal diepoxide of alloaureothin along with three carboxamides, 4-aminobenzoic acid, and 1,6-dimethoxyphenazine from the individual culture of Streptomyces luteireticuli NIIST-D31. Herein, cocultivation of NIIST-D31 with Streptomyces luteoverticillatus NIIST-D47 afforded two new stereochemical variants of streptophenazine (S1 and S2), and 1-N-methylalbonoursin, where the individual culture of NIIST-D47 primarily produced carbazomycins A, D, and E. The new streptophenazines and 1-N-methylalbonoursin were also observed during cocultivation of NIIST-D31 with Streptomyces thioluteus NIIST-D63, where the individual culture of NIIST-D63 strain afforded for the first time 2,2'-bipyridines (caerulomycinamide and dipyrimicin B), picolinamide, 2,3-dimethoxybenzamide, 2-hydroxy-3-methoxybenzamide, and 6-amino-2-pyridone along with known natural products aureothin and 1,6-dimethoxyphenazine. Finally, cocultivation of NIIST-D47 and NIIST-D63 strains produced carbazomycins B and C, alloaureothin, cyclo-(Leu-Pro), investiamide, and 4-aminobenzoic acid. Some of the compounds observed in the individual cultures were also produced in cocultivations. Improvement in the yield of secondary metabolites during cocultivation compared to individual culturing is well-known, which is noted here for vicinal diepoxide of alloaureothin. The production of new streptophenazines by cocultivation combinations with NIIST-D31 suggests that NIIST-D47 and NIIST-D63 may function as inducers in activating cryptic secondary metabolite-biosynthetic gene clusters. Cytotoxicity of the new streptophenazines in cancerous (MCF7 and MDA-MB-231) or non-cancerous (WI-38) cells were tested, however, they exhibited no significant activity.