Pharmazeutisches Institut, Abteilung Pharmazeutische Biologie, Christian-Albrechts-Universität zu Kiel, Gutenbergstraße 76, 24118 Kiel, Germany; Pharmazeutisches Institut, Abteilung Pharmazeutische und Medizinische Chemie, Christian-Albrechts-Universität zu Kiel, Gutenbergstraße 76, 24118 Kiel, Germany.
GEOMAR Centre for Marine Biotechnology, Research Unit Marine Natural Products Chemistry, GEOMAR Helmholtz Centre for Ocean Research Kiel, Am Kiel-Kanal 44, 24106 Kiel, Germany.
J Ethnopharmacol. 2019 Apr 6;233:94-100. doi: 10.1016/j.jep.2018.11.029. Epub 2018 Nov 23.
The oleoresin of Brazilian Copaifera reticulata is a traditional remedy used for the treatment of skin and urinary tract infections, respiratory diseases, rheumatism, ulcer and tumours; thus, playing an important role in the primary health care of the indigenous population.
As most previous pharmacological tests used the crude oleoresin and only a few studies so far dealt with enriched fractions or pure chemically defined compounds, the aim of this study was to systematically evaluate the antimicrobial and cytotoxic properties of the Copaifera reticulata oleoresin and to assign traditional uses to specific secondary metabolites.
The oleoresin, as well as its neutral and acidic fractions were tested for their activity against six cancer cell lines, two clinically relevant bacterial strains, and two dermatophytes. Both fractions were analysed by GC-MS and UHPLC-ELSD, respectively. The antibacterial acidic phase was further fractionated by preparative chromatography to purify and characterize the compounds responsible for the observed pharmacological effect.
Whereas no cytotoxic activity was detected, the crude oleoresin and its acidic fraction showed antibacterial activity against gram-positive bacteria Enterococcus faecium (IC values 4.2 and 4.8 µg/mL, respectively) and methicillin-resistant Staphylococcus aureus (MRSA, IC values 5.3 and 7.2 µg/mL, respectively). Purification of the acidic fraction of the C. reticulata oleoresin yielded two dicarboxylic diterpene acids and the four main diterpene acids, comprising three different diterpene scaffolds. Interestingly, the activity was not restricted to a particular diterpene-type but rather depended on the compounds' lipophilicity, with the most active constituent showing IC values of 1.6 (E. faecium) and 2.5 µg/mL (MRSA), respectively. Furthermore, ent-polyalthic acid, the major diterpenoid, was significantly active against dermatophytes with IC values of 6.8 µg/mL (Trichophyton rubrum) and 4.3 µg/mL against (T. mentagrophytes).
The present study proved the antimicrobial effects of the C. reticulata oleoresin and its diterpenoid constituents, confirming its wide use in folk medicine for the treatment of skin and urinary tract infections. The inhibitory activity of copaiba diterpenoids against dermatophytic fungi as well as the gram-positive bacteria E. faecium and MRSA is being reported for the first time, providing potential lead structures for the treatment of these clinically relevant bacterial strains.
巴西 Copaifera reticulata 的油树脂是一种传统的疗法，用于治疗皮肤和尿路感染、呼吸道疾病、风湿病、溃疡和肿瘤；因此，在原住民的初级保健中发挥着重要作用。
由于以前的药理学测试大多使用粗油树脂，而且到目前为止只有少数研究涉及富集馏分或纯化学定义的化合物，因此本研究旨在系统评估 Copaifera reticulata 油树脂的抗菌和细胞毒性特性，并将传统用途分配给特定的次生代谢物。
对油树脂及其中性和酸性馏分进行了测试，以评估其对六种癌细胞系、两种临床相关细菌株和两种皮肤真菌的活性。用 GC-MS 和 UHPLC-ELSD 分别对两种馏分进行分析。对具有抗菌活性的酸性馏分进行了制备色谱分离，以纯化和鉴定观察到的药理作用的化合物。
粗油树脂及其酸性馏分对革兰氏阳性菌粪肠球菌（IC 值分别为 4.2 和 4.8 µg/mL）和耐甲氧西林金黄色葡萄球菌（MRSA，IC 值分别为 5.3 和 7.2 µg/mL）具有抗菌活性，但未检测到细胞毒性。从 Copaifera reticulata 油树脂的酸性馏分中分离出两种二羧酸二萜酸和四种主要的二萜酸，包括三种不同的二萜骨架。有趣的是，活性不仅限于特定的二萜型，而是取决于化合物的亲脂性，最活跃的成分的 IC 值分别为 1.6（粪肠球菌）和 2.5 µg/mL（MRSA）。此外，ent-polyalthic 酸是主要的二萜类化合物，对皮肤真菌具有显著的活性，IC 值分别为 6.8 µg/mL（红色毛癣菌）和 4.3 µg/mL（须癣毛癣菌）。
本研究证明了 Copaifera reticulata 油树脂及其二萜类成分的抗菌作用，证实了其在民间医学中广泛用于治疗皮肤和尿路感染。 Copaiba 二萜类化合物对皮肤真菌以及革兰氏阳性菌粪肠球菌和 MRSA 的抑制活性是首次报道的，为治疗这些临床相关细菌株提供了潜在的先导结构。
