Investigating the Effectiveness of St John's Wort Herb as an Antimicrobial Agent against Mycobacteria

Mortensen, Trent; Shen, Shu-Jie; Shen, FenAnn; Walsh, Marie K.; Sims, Ronald C.; Miller, Charles D.

doi:10.1002/ptr.3716

Cited by 9 publications

(5 citation statements)

References 33 publications

(48 reference statements)

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“…SEM protocols were used as mentioned in [56]. Briefly, secreting and non-secreting strains were grown up overnight and fixed onto glass cover slips.…”

Section: Methodsmentioning

confidence: 99%

Secretion of polyhydroxybutyrate in Escherichia coli using a synthetic biological engineering approach

et al. 2013

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BackgroundPolyhydroxyalkanoates (PHAs) are a group of biodegradable plastics that are produced by a wide variety of microorganisms, mainly as a storage intermediate for energy and carbon. Polyhydroxybutyrate (PHB) is a short-chain-length PHA with interesting chemical and physical properties. Large scale production of PHB is not wide-spread mainly due to the downstream processing of bacterial cultures to extract the PHB. Secretion of PHB from Escherichia coli could reduce downstream processing costs. PHB are non-proteinaceous polymers, hence cannot be directly targeted for secretion. Phasin, PhaP1, is a low molecular weight protein that binds to PHB, reducing PHB granule size. In this study PHB is indirectly secreted with PhaP1 from E. coli via type I secretion using HlyA signal peptides.ResultsThis study demonstrated the successful secretion of phasin and phasin bound PHB outside of the cell and into the culture medium. The secretion of PHB was initiated between 24 and 48 h after induction. After 48 h of culturing, 36% of the total PHB produced in the secreting strain was collected in the secreted fraction and 64% remained in the internal fraction. To further support the findings of this study, the PHB secretion phenomenon was observed using SEM.ConclusionsFrom this study, the ability to use type I secretion to: 1) secrete phasin and 2) successfully secrete PHB has been shown.

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“…SEM protocols were used as mentioned in [56]. Briefly, secreting and non-secreting strains were grown up overnight and fixed onto glass cover slips.…”

Section: Methodsmentioning

confidence: 99%

Secretion of polyhydroxybutyrate in Escherichia coli using a synthetic biological engineering approach

et al. 2013

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“…The exact composition of oils and creams does, however, not seem to be very critical [10], and activity against gram-positive bacteria was even reported for hydrous SJW teas [27]. A comparison of SJW extract with its purified fractions containing hyperforin, hypericin, and pseudohypericin revealed that the extract inhibited growth of mycobacteria more effectively than the isolated components, indicating synergistic effects [28]. According to Peeva-Naumovska et al [29] a lipophilic Hypericum ointment for vaginal application was active against a number of bacteria but not Lactobacillus acidophilus which is part of the natural vaginal flora.…”

Section: Hydrophilicmentioning

confidence: 99%

Topical Application of St. Johnʼs Wort (Hypericum perforatum)

Seelinger²,

2013

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St. John's wort (Hypericum perforatum) has been intensively investigated for its antidepressive activity, but dermatological applications also have a long tradition. Topical St. John's wort preparations such as oils or tinctures are used for the treatment of minor wounds and burns, sunburns, abrasions, bruises, contusions, ulcers, myalgia, and many others. Pharmacological research supports the use in these fields. Of the constituents, naphthodianthrones (e.g., hypericin) and phloroglucinols (e.g., hyperforin) have interesting pharmacological profiles, including antioxidant, anti-inflammatory, anticancer, and antimicrobial activities. In addition, hyperforin stimulates growth and differentiation of keratinocytes, and hypericin is a photosensitizer which can be used for selective treatment of nonmelanoma skin cancer. However, clinical research in this field is still scarce. Recently, sporadic trials have been conducted in wound healing, atopic dermatitis, psoriasis, and herpes simplex infections, partly with purified single constituents and modern dermatological formulations. St. John's wort also has a potential for use in medical skin care. Composition and stability of pharmaceutical formulations vary greatly depending on origin of the plant material, production method, lipophilicity of solvents, and storage conditions, and this must be regarded with respect to practical as well as scientific purposes.

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“…We then determined the MBCs of LML with susceptible bacteria, four isolates of L. monocytogenes and three isolates of Mycobacterium. Scanning electron microscopy (SEM) was also conducted to identify changes in the cell surfaces after LML treatment (7).…”

mentioning

confidence: 99%