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1.
Appl Microbiol Biotechnol ; 101(10): 4009-4032, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28411325

RESUMO

Ginseng, an oriental gift to the world of healthcare and preventive medicine, is among the top ten medicinal herbs globally. The constitutive triterpene saponins, ginsenosides, or panaxosides are attributed to ginseng's miraculous efficacy towards anti-aging, rejuvenating, and immune-potentiating benefits. The major ginsenosides such as Rb1, Rb2, Rc, Rd., Re, and Rg1, formed after extensive glycosylations of the aglycone "dammaranediol," dominate the chemical profile of this genus in vivo and in vitro. Elicitations have successfully led to appreciable enhancements in the production of these major ginsenosides. However, current research on ginseng biotechnology has been focusing on the enrichment or production of the minor ginsenosides (the less glycosylated precursors of the major ginsenosides) in ginseng preparations, which are either absent or are produced in very low amounts in nature or via cell cultures. The minor ginsenosides under current scientific scrutiny include diol ginsenosides such as Rg3, Rh2, compound K, and triol ginsenosides Rg2 and Rh1, which are being touted as the next "anti-neoplastic pharmacophores," with better bioavailability and potency as compared to the major ginsenosides. This review aims at describing the strategies for ginsenoside production with special attention towards production of the minor ginsenosides from the major ginsenosides via microbial biotransformation, elicitations, and from heterologous expression systems.


Assuntos
Antineoplásicos/metabolismo , Bactérias/genética , Ginsenosídeos/biossíntese , Panax/metabolismo , Antineoplásicos/química , Bactérias/metabolismo , Biotransformação , Expressão Gênica , Ginsenosídeos/química , Ginsenosídeos/isolamento & purificação , Ginsenosídeos/uso terapêutico , Humanos , Panax/química , Panax/genética , Plantas Medicinais/química , Plantas Medicinais/genética
2.
Appl Microbiol Biotechnol ; 100(11): 4909-22, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26795963

RESUMO

Cobalt nitrate, nickel sulphate, hydrogen peroxide, sodium nitroprusside, and culture filtrates of Pseudomonas monteili, Bacillus circularans, Trichoderma atroviridae, and Trichoderma harzianum were tested to elicit ginsenoside production in a cell suspension line of Panax quinquefolius. Abiotic elicitors preferentially increased panaxadiols whereas biotic elicitors upregulated the panaxatriol synthesis. Cobalt nitrate (50 µM) increased total ginsenosides content by twofold (54.3 mg/L) within 5 days. It also induced the Rc synthesis that was absent in the control cultures. Elicitation with P. monteili (2.5 % v/v, 5 days) also supported 2.4-fold enhancement in saponin yield. Elicitation by T. atroviridae or hydrogen peroxide induced the synthesis of Rg3 and Rh2 that are absent in ginseng roots. The highest ginsenosides productivity (3.2-fold of control) was noticed in cells exposed to 1.25 % v/v dose of T. atroviridae for 5 days. Treating cells with T. harzianum for 15 days afforded maximum synthesis and leaching (8.1 mg/L) of ginsenoside Rh1.


Assuntos
Ginsenosídeos/biossíntese , Panax/química , Células Vegetais/efeitos dos fármacos , Bacillus/química , Cobalto/química , Meios de Cultura , Peróxido de Hidrogênio/química , Níquel/química , Nitroprussiato/química , Panax/citologia , Células Vegetais/metabolismo , Pseudomonas/química , Trichoderma/química
3.
Med Chem ; 20(4): 369-384, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38192143

RESUMO

The worldwide impact of cancer is further compounded by the constraints of current anticancer medications, which frequently exhibit a lack of selectivity, raise safety apprehensions, result in significant adverse reactions, and encounter resistance mechanisms. The current situation highlights the pressing need to develop novel and more precise anticancer agents that prioritize safety and target specificity. Remarkably, more than 85% of drugs with physiological activity contain heterocyclic structures or at least one heteroatom. Nitrogen-containing heterocycles hold a significant position among these compounds, emerging as the most prevalent framework within the realm of heterocyclic chemistry. This article explores the medicinal chemistry behind these molecules, highlighting their potential as game-changing possibilities for anticancer medication development. The analysis highlights the inherent structural variety in nitrogen-containing heterocycles, revealing their potential to be customized for creating personalized anticancer medications. It also emphasizes the importance of computational techniques and studies on the relationships between structure and activity, providing a road map for rational medication design and optimization. Nitrogen- containing heterocycles are a promising new area of study in the fight against cancer, and this review summarises the state of the field so far. By utilizing their inherent characteristics and exploiting cooperative scientific investigations, these heterocyclic substances exhibit potential at the forefront of pioneering therapeutic approaches in combating the multifaceted obstacles posed by cancer.


Assuntos
Antineoplásicos , Descoberta de Drogas , Compostos Heterocíclicos , Nitrogênio , Antineoplásicos/química , Antineoplásicos/farmacologia , Antineoplásicos/síntese química , Compostos Heterocíclicos/química , Compostos Heterocíclicos/farmacologia , Compostos Heterocíclicos/síntese química , Humanos , Nitrogênio/química , Neoplasias/tratamento farmacológico , Relação Estrutura-Atividade , Estrutura Molecular , Animais
4.
Med Chem ; 20(5): 487-502, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38279757

RESUMO

This study aims to provide a thorough analysis of nitrogen-containing heterocycles, focusing on their therapeutic implications for the development of targeted and effective antiviral drugs. To better understand how nitrogen-containing heterocycles can be used to create antiviral drugs, this review adopts a systematic literature review strategy to compile and analyze pertinent research studies. It combines information from various fields to understand better the compounds' mode of action and their therapeutic potential. This review paper summarizes data from multiple sources to highlight the promising potential of heterocycles containing nitrogen as promising possibilities for future antiviral treatments. The capacity to engage selectively and modulate critical pathways bodes well for their use in developing new viral therapies. In conclusion, nitrogen-containing heterocycles are shown to be of utmost importance in the field of medicinal chemistry, as emphasized by the review paper. It emphasizes the central importance of chemical insights and pharmacological potential in developing novel and effective antiviral medicines by bringing them together.


Assuntos
Antivirais , Compostos Heterocíclicos , Nitrogênio , Antivirais/farmacologia , Antivirais/química , Compostos Heterocíclicos/química , Compostos Heterocíclicos/farmacologia , Humanos , Nitrogênio/química , Animais
5.
Plant Sci ; 330: 111639, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36796649

RESUMO

Hsp101 chaperone is vital for survival of plants under heat stress. We generated transgenic Arabidopsis thaliana (Arabidopsis) lines with extra copies of Hsp101 gene using diverse approaches. Arabidopsis plants transformed with rice Hsp101 cDNA driven by Arabidopsis Hsp101 promoter (IN lines) showed high heat tolerance while the plants transformed with rice Hsp101 cDNA driven by CaMV35S promoter (C lines) were like wild type plants in heat stress response. Transformation of Col-0 plants with 4633 bp Hsp101 genomic fragment (GF lines) from A. thaliana containing both its coding and the regulatory sequence resulted in mostly over-expressor (OX) lines and a few under-expressor (UX) lines of Hsp101. OX lines showed enhanced heat tolerance while the UX lines were overly heat sensitive. In UX lines, silencing of not only Hsp101 endo-gene was noted but also transcript of choline kinase (CK2) was silenced. Previous work established that in Arabidopsis, CK2 and Hsp101 are convergent gene pairs sharing a bidirectional promoter. The elevated AtHsp101 protein amount in most GF and IN lines was accompanied by lowered CK2 transcript levels under HS. We observed increased methylation of the promoter and gene sequence region in UX lines; however, methylation was lacking in OX lines.


Assuntos
Arabidopsis , Proteínas de Choque Térmico , Proteínas de Plantas , Termotolerância , Arabidopsis/metabolismo , DNA Complementar/metabolismo , Regulação da Expressão Gênica de Plantas , Proteínas de Choque Térmico/metabolismo , Temperatura Alta , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo , Termotolerância/genética , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
6.
Protoplasma ; 256(6): 1463-1486, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31297656

RESUMO

The saponins are a diverse class of natural products, with a broad scale distribution across different plant species. Chemically characterized as triterpenoid glycosides, they posses a 30C oxidosqualene precursor-based aglycone moiety (sapogenin), to which glycosyl residues are subsequently attached to yield the corresponding saponin. Based on the chemically distinct aglycone moieties, broadly, they are divided into triterpenoid saponins (dammaranes, ursanes, oleananes, lupanes, hopanes, etc.) and the sterol glycosides. This review aims to present in detail the biosynthesis patterns of the different aglycones from a common precursor and their glycosylation patterns to yield the functionally active glycoside. The review also presents recent advances in the pharmacological activities of these saponins, particularly as potent anti-neoplastic pharmacophores, antioxidants, or anti-viral/antibacterial agents. Since alternate production pedestals for these pharmacologically important triterpenes via cell and tissue cultures are an attractive option for their sustainable production, recent trends in the variety and scale of in vitro production of plant triterpenoids have also been discussed.


Assuntos
Plantas/química , Saponinas/química , Triterpenos/química
7.
Protoplasma ; 255(4): 1147-1160, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29450757

RESUMO

Dual metabolite, i.e., ginsenoside and anthocyanin, co-accumulating cell suspensions of Panax sikkimensis were subjected to elicitation with culture filtrates of Serratia marcescens (SD 21), Bacillus subtilis (FL11), Trichoderma atroviridae (TA), and T. harzianum (TH) at 1.25% and 2.5% v/v for 1- and 3-week duration. The fungal-derived elicitors (TA and TH) did not significantly affect biomass accumulation; however, bacterial elicitors (SD 21 and FL11), especially SD 21, led to comparable loss in biomass growth. In terms of ginsenoside content, differential responses were observed. A maximum of 3.2-fold increase (222.2 mg/L) in total ginsenoside content was observed with the use of 2.5% v/v TH culture filtrate for 1 week. Similar ginsenoside accumulation was observed with the use of 1-week treatment with 2.5% v/v SD 21 culture filtrate (189.3 mg/L) with a 10-fold increase in intracellular Rg2 biosynthesis (31 mg/L). Real-time PCR analysis of key ginsenoside biosynthesis genes, i.e., FPS, SQS, DDS, PPDS, and PPTS, revealed prominent upregulation of particularly PPTS expression (20-23-fold), accounting for the observed enhancement in protopanaxatriol ginsenosides. However, none of the elicitors led to successful enhancement in in vitro anthocyanin accumulation as compared to control values.


Assuntos
Ginsenosídeos/genética , Ginsenosídeos/metabolismo , Panax/química , Raízes de Plantas/química , Meios de Cultura , Suspensões
8.
Protoplasma ; 252(2): 697-703, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25178251

RESUMO

The age-dependent production kinetics of ginsenosides and an anthocyanin pigment in a cell suspension line of Panax sikkimensis was followed in vitro. Highest total saponin content [7.37 mg/g dry weight (DW)] and biomass accumulation (% biomass increase = 209.67) in this line occurred after 3 and 5 weeks of culture, respectively. Accumulation of individual protopanaxatriol (Re, Rg1, and Rg2) and protopanaxadiol (Rb1, Rb2, and Rc) ginsenosides showed a variable pattern of accumulation independent of cell biomass buildup during the 7-week culture cycle. However, total content of triol ginsenosides was always significantly more than the diol group of ginsenosides, being 183.2-, 63.5-, and 72.1-folds at third, fourth, and fifth week stage of cell growth. Interestingly, in addition to these ginsenosides, the cell line also co-accumulated an anthocyanin pigment in vitro. The pigment content increased gradually from 8.66 to 14.29 mg/g DW after first to fifth week followed by a marginal fall to 12.79 and 10.95 mg/g DW during next 2 weeks. Therefore, in terms of total recovery of saponins (77.4 mg/l) and anthocyanin (199.16 mg/l), harvesting of cells after 3 and 5 weeks of growth was most profitable, respectively. The possible utility of this dual purpose cell line in nutraceutical industry is discussed.


Assuntos
Antocianinas/biossíntese , Ginsenosídeos/biossíntese , Panax/citologia , Extratos Vegetais/biossíntese , Antocianinas/isolamento & purificação , Linhagem Celular , Proliferação de Células , Cromatografia Líquida de Alta Pressão , Ginsenosídeos/isolamento & purificação , Panax/metabolismo , Extratos Vegetais/isolamento & purificação
9.
Nat Prod Res ; 29(13): 1256-63, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25813381

RESUMO

The present study aims at developing an extraction protocol for efficient ginsenoside recovery from cell suspensions of Panax quinquefolius and P. sikkimensis. Methanol (100%, 70% and 30%), water (40°C, 90°C), water-saturated butanol and butanol-saturated water were compared for their ultrasonication-assisted ginsenoside retrieval efficacy. HPLC and HP-TLC analysis revealed 100% methanol as the best solvent for maximum retrieval of Rb (diol) and Rg (triol) ginsenosides (P. quinquefolius: Rb: 0.189, Rg: 3.163 mg/g DW; P. sikkimensis: Rb: 0.245, Rg: 4.073 mg/g DW), followed by water (90°C). Methanolic solutions, especially 70%, proved to be significant retrievers of Rg1 (1.812 and 1.327 mg/g DW in P. quinquefolius and P. sikkimensis), with poor Re recovery (0.328 and 0.342 mg/g DW). Water-saturated butanol also led to significant ginsenoside extraction (72.4% of content extracted by methanol), selectively in P. quinquefolius, with a less than 50% of total content extracted by methanol, in P. sikkimensis.


Assuntos
Ginsenosídeos/isolamento & purificação , Panax/química , Linhagem Celular , Cromatografia Líquida de Alta Pressão , Metanol , Solventes , Ultrassom , Água
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