Secondary metabolites in organic and conventional crops and diets, and their human bioavailability

The overall objective of the PhD project is to study the impact of growth system on the content of selected and presumably health-promoting bioactive secondary metabolites in certain crops of high abundance in the human diet. Additionally, the project aim is to study the content of selected bioactive secondary metabolites in human diets and discuss their possible health effects based on literature search and selected analysis of human samples from a human intervention study based on the same cultivated crops as mentioned above. In conclusion, this study showed that the content of presumable health-promoting secondary metabolites was not significantly different between organic and conventional food products, even though cultivation studies are considered as the most well-controlled and valid comparative studies. Hence, the perception about organic food products being healthier than conventional was not supported and can most likely not be attributed the secondary metabolites included in the present study, although further knowledge about the bioavailability is needed. The study broadens the knowledge about organic food products indicating that the selected secondary metabolites (carotenoids, flavonoids, phenolic acids and polyacetylenes) are not of major importance for their expected health effects, which is of interest to both the consumer of organic food products and scientist working in the area of organic agricultur

Identification of Secondary Metabolites From Ethanol Extract of Ciplukan (Physalis Angulate) Leaves and Toxicity Test on Post-Larvae of Tiger Shrimp (Penaeus Monodon) [Identifikasi Senyawa Metabolit Sekunder Ektrak Etanol Daun Ciplukan (Physalis Angulata) Dan Uji Toksisitas Terhadap Sintasan Post Larva Udang Windu (Penaeus Monodon)]

Physalis angulata merupakan tumbuhan pekarangan yang telah banyak dimanfaatkan sebagai tumbuhan obat oleh masyarakat. Tumbuhan ini diduga memiliki metabolit sekunder yang dapat dimanfaatkan sebagai obat dan peningkatan nutrisi. Penelitian ini bertujuan untuk mengindentifikasi senyawa metabolik sekunder dan toksisitasnya terhadap sintasan post larva (PL) udang windu. Penelitian ini dilakukan dengan beberapa tahapan (1). Ekstraksi P. angulata dengan menggunakan etanol, (2) Uji GCMS P. angulata, (3) Identifikasi metabolit sekunder dari P. angulata (4) Uji LC50 (Lethal Concentration 50) dan (5) Analisis data. Berdasarkan hasil analisis GCMS menunjukkan bahwa P. angulata mengandung metabolit sekunder golongan senyawa antara lain fenol, steroid, asam lemak, terpenoid, benzene dan alkaloid. Senyawa- senyawa yang terkandung tersebut diduga dapat dijadikan sebagai pengembangan budidaya udang pada penanggulangan penyakit, percepatan pertumbuhan dan peningkatan kualitas telur. Sedangkan hasil uji toksisitas dengan menggunakan larva udang windu selama 48 jam menunjukkan bahwa konsentrasi aman yang dapat digunakan untuk pengembangan udang dengan memanfaatkan ekstrak ciplukan dengan konsentrasi 13,1 mg/l

Secondary Metabolites

Plants are the main source for obtaining secondary metabolites that are used in the pharmaceutical, cosmetic and food industries. In nature, the performance of bioactive compounds is affected by biotic and abiotic factors, an alternative to overcome this adversity is in vitro plant cultures and particularly plant cell culture that has multiple advantages, highlighting the possibility of controlling variables to increase the content. of compounds of interest. The objective of this research was to determine and optimize the effect of some elicitors on the production of secondary flavonoid metabolites in suspension cell cultures of Thevetia peruviana on a shake flask scale. The experimental part was performed from cell cultures in suspension cells of T. peruviana maintained by the Bioconversion Laboratory of the Universidad Nacional de Colombia, sede Medellin. Firstly, methyl jasmonate (MeJa) 3 µM and salicylic acid (SA) 300 µM were added to two los of cell cultures, that circumstantially they differed in their time suspension state lot 1 (9 months) and lot 2 (3 months). Secondly, certain were evaluated, in order to be optimized; the operational parameters cosidered were: day of addition, concentration and hours of harvest. Finally, the combined effect of MeJa (0.3 µM) and SA (100 µM) was determined in different proportions, the day of elicitation and the hours of harvest were constant. Flavonoid content was quantified by UV-vis spectrophotometry usinfg the AlCl3 complexation method and was evaluated at extracellular and intracellular level. In the first part, at intracellular level, SA generated 14.6 % and 9.56 % more flavonoid content than MeJa in lots 1 and 2, respectively. In the second part, 4.14 mg EQ/g DW were generated with MeJa 0.3 µM, elicitation day 5 and harvest at 90 h; 3.75 mg EQ/g DW were generated with 100 µM SA, elicitation day 0 and harvests at 96 h. In the third part, 4.62 mg EQ / g DW were generated with the combination of MeJa (0.3 µM) – SA (100 µM) in a ratio of 20-80, elicitation on day 0 and harvest at 96 h. Eliciting cell cultures of Thevetia peruviana with MeJa and SA under optimal conditions of concentration, day of addition and hours of harvest increased the content of flavonoid compounds. The results obtained could serve as a basis for the development of investigations at the bioreactor scale.Las plantas son la principal fuente para la obtención de metabolitos secundarios que se usan en la industria farmacéutica, cosmética y alimentaria. En la naturaleza el rendimiento de compuestos bioactivos se ve afectado por factores bióticos y abióticos, una alternativa para superar esta adversidad son los cultivos vegetales in vitro y particularmente el cultivo de células en suspensión que presenta múltiples ventajas destacándose la posibilidad de controlar variables para aumentar el contenido de compuestos de interés. El objetivo del presente trabajo de investigación fue determinar y optimizar el efecto de algunos elicitores sobre la producción de metabolitos secundarios tipo flavonoides en cultivos de células en suspensión de Thevetia peruviana a escala de matraz agitado. La parte experimental se realizó a partir de cultivos de células en células en suspensión de T. peruviana que mantenía el laboratorio de bioconversiones de la Universidad Nacional de Colombia sede Medellín. Primeramente, metil jasmonato (MeJa) 3 μM y ácido salicílico (AS) 300 μM se adicionaron a dos lotes de cultivos de células; que circunstancialmente diferían en su tiempo en estado de suspensión lote 1 (9 meses) y lote 2 (3 meses). Segundamente, determinadas condiciones fueron evaluadas, con el fin de ser optimizadas; los parámetros operacionales que se consideraron fueron: día de adición, concentración y las horas de cosecha. Por último, el efecto combinado de MeJa (0,3 μM) – AS (100 μM) se determinó en diferentes proporciones, el día de elicitación y las horas de cosecha fueron constantes. El contenido de flavonoides se cuantificó por espectrofotometría UV – vis por el método de complejación de AlCl3 y se evaluaron a nivel extracelular e intracelular. En la primera parte, a nivel intracelular AS generaron 14,6 % y 9,56 % más contenido de flavonoides que MeJa en lotes 1 y 2, respectivamente. En la segunda parte, 4,14 mg EQ/g MS fueron generados con MeJa 0,3 μM, elicitación día 5 y cosecha a 90 h; por otro lado, 3,75 mg EQ/g MS fueron generados con AS 100 μM, elicitación día 0 y cosecha a 96 h. En la tercera parte, 4,62 mg EQ/g MS fueron generados con la combinación de MeJa (0,3 μM) – AS (100 μM) en proporción 20 – 80, elicitación el día 0 y cosecha a las 96 h. Elicitar cultivos celulares de Thevetia peruviana con MeJa y AS en condiciones óptimas de concentración, día de adición y horas de cosecha incrementaron el contenido de compuestos flavonoides. Los resultados obtenidos podrían servir como base para el desarrollo de investigaciones a escala de biorreactor.Maestrí

Bioactive secondary metabolites with multiple activities from a fungal endophyte

In order to replace particularly biohazardous nematocides, there is a strong drive to finding natural product-based alternatives with the aim of containing nematode pests in agriculture. The metabolites produced by the fungal endophyte Fusarium oxysporum 162 when cultivated on rice media were isolated and their structures elucidated. Eleven compounds were obtained, of which six were isolated from a Fusarium spp. for the first time. The three most potent nematode-antagonistic compounds, 4-hydroxybenzoic acid, indole-3-acetic acid (IAA) and gibepyrone D had LC50 values of 104, 117 and 134 μg ml−1, respectively, after 72 h. IAA is a well-known phytohormone that plays a role in triggering plant resistance, thus suggesting a dual activity, either directly, by killing or compromising nematodes, or indirectly, by inducing defence mechanisms against pathogens (nematodes) in plants. Such compounds may serve as important leads in the development of novel, environmental friendly, nematocides

Phytotoxic metabolites produced by Botryosphaeriaceae involved in grapevine trunk diseases

Fungi belonging to the Botryosphaeriaceae family are well known as cosmopolitan pathogens, saprophytes and endophytes and occur on a wide range of hosts including grapevine. More recently, a new species of Lasiodiplodia was isolated from declining grapevines in Sardinia (Italy). This still undescribed species showed to produce in liquid culture several phytotoxic secondary metabolites. In this communication the chemical and biological characterization of these bioactive secondary metabolites is discussed together with their role in the pathogenesis process

Secondary Metabolites and Nutrient Balance in Casuarinas: an Insight Into Protein Competition Model (PCM)

The total phenolics, total condensed tannins (TCT), nitrogen (N) and total protein (TP) in needles of Casuarina equisetifolia and Casuarina junghuhniana were studied to understand the carbon-nutrient balance (CNB) and the growth-differentiation balance (GDB) hypotheses. The carbon-nutrient balance (CNB) hypothesis postulates that phenolic levels in plants are determined by the balance between carbon and nutrient availability1. The growth-differentiation balance (GDB) hypothesis2 considers factors that limit growth and differentiation. The production of phenolics dominates when factors other than photosynthate supply are suboptimal for growth (e.g., under nutrient limitation). Resource-based theories assume that the synthesis of defensive compounds is constrained by the external availability of resources and internal trade-offs in resource allocation between growth and defense. It is stated that growth processes dominate over the production of defensive compounds and that more carbon is left for defensive compounds only when plant growth is restricted by a lack of mineral nutrient (emphasized by the CNB hypothesis) or by any factor (according to the GDB hypothesis). Jones and Hartley3 presented a protein competition model (PCM) for predicting total phenolics allocation and content in leaves of higher plants. Protein competition model (PCM) stated that “protein and phenolics synthesis compete for the common, limiting resource phenylalanine,” so nitrogen (N) rather than C is the limiting resource for synthesis of phenolics. In our study, the contents of Total Phenolics, and Total Condensed Tannin (TCT) in needles of C. equisetifolia were higher than the C. junghuhniana. However, Total protein and nitrogen (N) contents were higher in C. junghuhniana than C. equisetifolia. There was a significant negative correlation between Total phenolics, TCT and Total Protein, N contents. Therefore, it is found from the present investigation that C. equisetifolia follows CNB hypothesis. However, C. junghuhniana follows GDB hypothesis, since it contains low defense chemicals viz., phenolics & TCT and high nitrogen and protein contents. Hence, the adaptability of C. equisetifolia in coastal areas and C. junghuhniana in drier inland condition is realized

Secondary Metabolites from the Marine Sponge Genus Phyllospongia.

Phyllospongia, one of the most common marine sponges in tropical and subtropical oceans, has been shown to be a prolific producer of natural products with a broad spectrum of biological activities. This review for the first time provides a comprehensive overview of secondary metabolites produced by Phyllospongia spp. over the 37 years from 1980 to 2016

Diversity of secondary metabolites from Genus Artocarpus (Moraceae)

Abstrak. Hakim A. 2010. Keanekaragaman metabolit sekunder Genus Artocarpus (Moraceae). Nusantara Bioscience 2:146-156. Beberapa spesies dari genus Artocarpus (Moraceae) telah diteliti kandungan bahan alamnya. Metabolit sekunder yang berhasil diisolasi dari genus Artocarpus terdiri dari terpenoid, flavonoid, stilbenoid, arilbenzofuran, neolignan, dan adduct Diels-Alder. Kelompok flavonoid merupakan senyawa yang paling banyak ditemukan dari tumbuhan Artocarpus. Senyawa flavonoid yang telah berhasil diisolasi dari tumbuhan Artocarpus memiliki kerangka yang beragam seperti calkon, flavanon, flavan-3-ol, flavon sederhana, prenilflavon, oksepinoflavon, piranoflavon, dihidrobenzosanton, furanodihidrobenzosanton, piranodihidrobenzosanton, kuinonosanton, siklolopentenosanton, santonolid, dihidrosanton. Kata kunci: Artocarpus, Moraceae, flavonoid, Diels-Alder, metabolit sekunder

Streptomyces Secondary Metabolites

Actinobacteria are found spread widely in nature and particular attention is given to their role in the production of various bioactive secondary metabolites. Tests on soil samples show that there can be a diversity of actinomycetes depending on the climate, the area it is growing in, how dry the soil is, and the quality of the soil. However, it was agreed after tests in Yunnan, China, that the genus Streptomyces sp. is most important in ecological function, representing up to 90% of all soil actinomycetes, and therefore helping to show the important characteristics needed of the soil actinomycete population. Streptomycete compounds are used for other biological activities, not just for antibiotics. It has been found that metabolites can be broadly divided into four classes: (1) regulatory activities in compounds, these include consideration of growth factors, morphogenic agents and siderophores, and plants promoting rhizobia; (2) antagonistic agents, these include antiprotozoans, antibacterials, antifungals, as well as antivirals; (3) agrobiologicals, these include insecticides, pesticides, and herbicides; and (4) pharmacological agents, these include neurological agents, immunomodulators, antitumorals, and enzyme inhibitors. It is found that Streptomyces hygroscopicus is one of the very best examples because it secretes in excess of 180 secondary metabolites to locate simultaneous bioactivities for a given compound. Increasingly, both its agricultural and pharmacological screenings are being used in conjunction with antimicrobial tests and have revealed several unusual aerobiological and therapeutic agents, which were hitherto unknown for biological use as antibiotics. Since streptomycetes are now being used increasingly to screen for antimicrobial activity, reports show the existence of secondary metabolites with other activities that may have been missed. Currently, nearly 17% of biologically active secondary metabolites (nearly 7600 out of 43,000) are known from streptomycetes. It has been found that soil streptomycetes are the main source used by bioactive secondary metabolites. However, recently there have been many and varied types of structurally unique and biologically active secondary metabolites found and obtained from marine actinomycetes, including those from the genus Streptomyces. Also, compounds that are synthesized by streptomycetes exhibit extreme chemical diversity. Diverse form made from from simple amino acid derivatives to high molecular weight proteides, and macrolactones from simple eight membered lactones to different condensed macrolactones. Berdy (1974) introduced the first classification scheme for antibiotics referring to the chemical structure. On the basis of Berdy’s scheme, (1996) recognized that both low and high molecular weight compounds from 63 different chemical classes are produced by streptomycetes

The expression profile of secondary metabolites in biofilms of B. amyloliquefaciens CECT 8237 biocontrol strain

The contribution of Bacillus amyloliquefaciens CECT 8237 (UMAF6639) strain to the plant protection against bacterial and fungal pathogens is mainly based on: i) the production of antimicrobial compounds, ii) the plant-growth promotion capability and iii) the induction of systemic resistance in plant host. In previous works, we demonstrated the relevant implication of the three families of lipopeptides in the biocontrol activity and biofilm formation on melon leaves. The analysis of the genome sequence revealed features previously identified in other Bacillus strains, such as genes related to biofilm formation, phytostimulation and induction of systemic resistance in the host plant, and novel genomic regions non-conserved within the Bacillus genus, and therefore with potential genes implicated in the biocontrol activity. Considering the relevance of biofilm formation and production of secondary metabolites in biocontrol, we analyzed the expression profile of several secondary metabolites produced by CECT 8237 in biofilm inducing conditions. To do so, we optimized an in situ detection method based on MALDI-TOF analysis of secondary metabolites within the bacterial colony and in supernatants and pellicles of B. amyloliquefaciens biofilms. We found a major accumulation of these secondary metabolites in the core and middle area of the colony and in the spent medium compared to pellicle. Further studies will help elucidating the real implication of these molecules in the bacterial ecology or in its mechanisms of defence, against competitors, and/or offense, against pathogens and its possible relation with the niche they occupy. This work was supported by grants from the Plan Nacional I+D+I (AGL-2012-31968) and Incentivos a Proyectos de Excelencia de la Junta de Andalucía (P10-AGR-57-97), both cofinanced by FEDER funds (EU). This work was also supported by grant from Koppert B.V. (8.06/60.4086) and European Research Council-Starting Grant BacBio ERC637971.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech