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Medicinal Plants Against COVID-19
Published in Hanadi Talal Ahmedah, Muhammad Riaz, Sagheer Ahmed, Marius Alexandru Moga, The Covid-19 Pandemic, 2023
Binish Khaliq, Naila Ali, Ahmed Akrem, M. Yasin Ashraf, Arif Malik, Arifa Tahir, M. Zia-Ul-Haq
Later in 2020, Jo, and his colleagues examined the activity of 64 flavonoids as SARS-CoV-3CL(pro) inhibitors by FRET method and reported that rhoifolin, herbacetin, and pectolinarin (20 µM) unveiled extreme prohibitory effect with IC50 = 27.45, 33.17, and 37.78 mM, correspondingly [49]. Furthermore, molecular docking, proved that the structure of flavonoids comprised of aromatic rings, which are hydrophobic and hydroxyl groups which are hydrophilic in nature which showed significant binding affinity to active sites of SARS-Coronavirus-3CL (pro) (Figure 9.3).
Entheogenesis and Entheogenic Employment of Harmal
Published in Ephraim Shmaya Lansky, Shifra Lansky, Helena Maaria Paavilainen, Harmal, 2017
Ephraim Shmaya Lansky, Shifra Lansky, Helena Maaria Paavilainen
Ephedra is not known as an entheogenic plant, though there are thousands of years of experience with it in China as ma huang, a hot and dry herb well-known for its benefit in treating asthma. Although ephedrine has long been considered as a kind of active component, there is improved safety in using complex extracts of Ephedra or even alkaloids extracted from the plant than synthetically obtained compounds. Unlike Ruta, it would be hard to mistake Ephedra for Peganum in the field, so it does not seem much of a replacement for Peganum. Yet as a complement it is most intriguing. In Israel, it is known as sharvitan, widely growing wild throughout the country. Following the report a few years ago, which appeared in an Israeli newspaper, of a farmer whose goat (or sheep?) was apparently cured of her visible cancerous tumors, tea made from Ephedra stems has become very popular as a folk remedy for cancer among the Israeli public according to direct clinical observations of ESL. Recently, investigations on the anticancer potential of sharvitan, ma huang/Ephedra have begun and are showing great promise, clearly elucidating advantages of complex products over purified ephedrine alkaloids (Hyuga et al. 2016) and identifying non-ephedrine compounds, such as the flavonoid herbacetin, which may serve as an entourage compound contributing to an anticancer effect within the plant, and a useful marker for maintaining quality control within the Ephedra extract (Oshima et al. 2016). Therefore, the opportunity for designing and executing trials to investigate synergy between Peganum and Ephedra, particularly in the anticancer arena, beckons (Figures 3.8 and 3.9).
Inhibition of SARS-CoV 3CL protease by flavonoids
Published in Journal of Enzyme Inhibition and Medicinal Chemistry, 2020
Seri Jo, Suwon Kim, Dong Hae Shin, Mi-Sun Kim
To elucidate the relationship between binding mode and binding affinity, a docking study for herbacetin homologues, kaempferol and morin, were also performed. The glide scores of three compounds were –9.263, –8.526 and –8.930, respectively. The tendency of the glide scores is matched with the binding affinity of the compounds. The comparison of the predicted binding modes of three complex structures showed critical factors governing their binding affinity. In common, they share the kaempferol motif. As shown in Figure 4, the phenyl moiety of kaempferol occupies the S1 site of SARS-CoV through a hydrogen bond with Glu166. In contrast, the chromen-4-one scaffold of kaempferol locates in the S2 site. In herbacetin, total of four hydrogen bonds are formed within a distance of 2.33 Å in the S2 site. Especially, the major binding force was driven by the presence of the additional 8-hydroxyl group which plays a critical role in binding with Glu166 and Gln189. These bindings are predicted to confer a good glide score of herbacetin. In contrast, the binding modes of morin and kaemperol become different due to the absence of above two hydrogen bonds due the lack of the 8-hydroxyl group (Figure 4). The absence also induces the change nullifying the hydrogen bond formed by the 5-hydroxyl group of the chromen-4-one scaffold with Asp187 observed in herbacetin. Though there is a new hydrogen bond formed through the 3-hydroxyl group, it may not enough to overcome the loss of binding capacity induced by the 8-hydroxyl group. This survey shows the importance of the 8-hydroxyl group at the strong binding affinity of herbacetin.
Flavonoids with inhibitory activity against SARS-CoV-2 3CLpro
Published in Journal of Enzyme Inhibition and Medicinal Chemistry, 2020
Seri Jo, Suwon Kim, Dae Yong Kim, Mi-Sun Kim, Dong Hae Shin
In the previous results of SARS-CoV 3CLpro21, only the three effect flavonoids (herbacetin, pectolinarin, and rhoifolin) were mentioned. However, other four flavonoids (orientin, baicalin, homoplantaginin, and rutin) were also detected though their efficiency was low (data not shown). It is actually expected due to the 96% sequence identity of the two 3CLpro. Interestingly, the affinity of rhoifolin became weaken but the affinity of baicalin became stronger with SARS-CoV-2 3CLpro. The efficiency of two flavonoids (herbacetin and pectolinarin) was still promising. Considering almost the same active site composition of both 3CLpros, the different binding affinity seemed to be a bit strange. However, this difference could be explained by the two factors. At first, the difference may be originated from the different constructs used in both cases. In this study, we used the whole SARS-CoV-2 3CLpro but the catalytic domain of SARS-CoV 3CLpro (amino acids Met1-Thr196) had been used in the previous study. In the crystal structures of both 3CLpros, there is a dimerisation domain influencing proteolytic activity. That domain was not in the previous SARS-CoV 3CLpro study. Nevertheless, a long incubation result showed that the proteolytic function of the SARS-CoV 3CLpro is still present without the dimerisation domain. Second, there are some different residues comprising active site residues. Ser46 and Val86 in SARS-CoV-2 3CLpro are replaced by Ala46 and Leu86 in SARS-CoV 3CLpro, respectively. Though their substitution seems to be minor in amino acid properties, the different residues may clearly contribute different affinities.
Rhodiosin and herbacetin in Rhodiola rosea preparations: additional markers for quality control?
Published in Pharmaceutical Biology, 2019
Zoltán Péter Zomborszki, Norbert Kúsz, Dezső Csupor, Wieland Peschel
Later studies usually refer to ‘roots’ with assumed diverse mixtures of roots and rhizomes. Reported quantities for single flavonoids vary, as do species provenance, plant part, and extraction solvent (when information is available). Data are mostly obtained in the context of isolation and identification works but not from validated quantitative analysis. Overall, 1 is typically the main finding alongside 2, rhodionin and kaempferol. Reports are available on isolations of 1 (19 mg/g) and rhodionin (17 mg/g) from ‘root’ (80% EtOH extract) (Kwon et al. 2009), of 1 (1.7–2.5 mg/g), rhodionin (0.14–0.3 mg/g), 2 (0.51–1.5 mg/g) and kaempferol (0.78–1.5 mg/g) from ‘root’ (unspecified extract) (C. Ma et al. 2013) and later of 1 (22.9 mg/g), rhodionin (13.3 mg/g), 2 (5.5 mg/g) and kaempferol (6.9 mg/g) from ‘root’ (unspecified extract) (Ma et al. 2014). Roots of R. sachalinensis were also investigated and 1 (7.13 mg/g) alongside rhodionin (3.98 mg/g), kaempferol (8.94 mg/g), afzelin (2.82 mg/g), multiflorin B (1.0 mg/g) and kaempferol-3,4′-di-O-β-d-glucopyranoside (0.4 mg/g) were detected in the dry extract (80% acetone) (Choe et al. 2012). Another study reported quantities of rhodionin in the range of 0.04–5.7 mg/g (methanol/EtOAc from ‘roots and rhizomes’) in 14 Asian Rhodiola species (R. rosea not included) without information on the content of other flavonoids (Li and Zhang 2008). Furthermore, overground parts of R. rosea showed 1 and 2 among 15 gossypetin, kaempferol, and quercetin glycosides (Petsalo et al. 2006). In summary, while 1 does not appear to be unique neither to the species R. rosea, nor to any of the plant parts, its general appearance and quantitative prevalence suggest that it could serve as a potential quality marker for Rhodiolae roseae rhizoma et radix. We assume that the subordinated aglycon herbacetin is a natural co-constituent of the plant rather than an artefact originating from drying, extraction or analytical processing. Based on our method no other flavonoids such as rhodionin or kaempferol were identified in our rhizome and root extracts of R. rosea.