Quality Standards for Herbal Drugs and Herbal Drug Preparations - Appropriate or Improvements Necessary?

Standards for quality control as defined in the European Pharmacopoeia contribute significantly to a consistent and high quality of herbal drugs, herbal drug preparations, and herbal medicinal products. The minimum content of single plant constituents is considered of high relevance. Therefore, nearly all monographs on herbal drugs or herbal drug preparations contain an obligatory assay.However, a critical evaluation of the data published for such assayed constituents reveals that in most cases these constituents have to be considered as purely analytical markers without correlation to quality or efficacy. Examples where the assay does not meet its objective support the need to adapt current quality standards. Moreover, the trend to increase the content of certain constituents may lead to significant modifications to traditional manufacturing processes.In order to initiate a scientific discussion, the role of the assay in the context of quality requirements, quality documentation in the manufacturing process, safety, and efficacy is discussed and possible alternatives to the single marker assay are examined.

Nephroprotective effects of red beetroot-based beverages against gentamicin-induced renal stress.

The objective of this study was to assess the nephroprotective effects of red beetroot-based beverages to ameliorate gentamicin-induced renal stress. For the purpose, normal and nephrotoxicity-induced Sprague Dawley rats were pretreated with beetroot-based beverages (8 ml/kg per day) for 8 weeks. In nephrotoxicity-induced rats, renal stress was induced by administration of gentamicin at 85 mg/kg b.w. per day during the last week of the trial. Afterward, overnight-fasted rats were sacrificed, and their sera and kidneys were analyzed for renal health biomarkers which revealed ameliorative effect of red beet beverages. Particularly, the antioxidant enzymes in renal tissues and serum proteins were significantly improved, whereas lipid peroxidation, nitric oxide, urea and creatinine levels were momentously reduced in nephrotoxicity-induced rats. Furthermore, histological assessment indicated better renal portfolio in the rats treated with beet beverages. The findings suggested that red beetroot-based beverages promisingly ameliorate negative impacts of gentamicin-induced nephritic stress. PRACTICAL APPLICATIONS: High rates of morbidity arising from metabolic disorders have shifted the trends toward use of functional foods and nutraceuticals as a safer approach to avoid such ailments. This research checked the nephroprotective effect of beetroot-based beverages instead of extracts of red beetroot. The findings of this research support the use of red beetroot-based beverages as a promising approach to alleviate renal stress. Furthermore, dietary supplementation of functional products and nutraceutics derived from beetroot may be synchronized in clinical practices in future after sufficient research to avoid the onset of various degenerative disorders originating from oxidative/nitrosative stress. Before employing this dietary model to humans, further investigation is necessitated to observe safety in long-term administration of such products. Besides, therapeutic dietary modules can also be devised for already suffering individuals to manage the severity of the disease and help improving health.

Findings on the heavy metal content in herbal drugs and essential oils - an update.

In this contribution, data for 7 elemental impurities originating from quality control analysis of manufacturers of herbal products is evaluated in light of the current requirements of the European Pharmacopoeia (Ph. Eur.) and the European legislative framework. The data shows that the Ph. Eur. limits set for cadmium, lead and mercury in herbal drugs are in principle still appropriate. The probability of herbal drugs exceeding the limits for arsenic, cobalt, nickel and vanadium (based on the ICH Q3D guideline for elemental impurities) appears to be very low, and consequently, it is proposed that general limits for these elements in herbal drugs in the Ph. Eur. are not required. For essential oils, there does not appear to be a risk of heavy metal contamination and a general test on heavy metals is not considered necessary.

Xanthohumol and related prenylflavonoids from hops and beer: to your good health!

Xanthohumol (3'-[3,3-dimethyl allyl]-2',4',4-trihydroxy-6'-methoxychalcone) is the principal prenylated flavonoid of the female inflorescences of the hop plant ('hops'), an ingredient of beer. Human exposure to xanthohumol and related prenylflavonoids, such as 8-prenylnaringenin and isoxanthohumol, is primarily through beer consumption. Xanthohumol has been characterized a 'broad-spectrum' cancer chemopreventive agent in in vitro studies, while 8-prenylnaringenin enjoys fame as the most potent phytoestrogen known to date. These biological activities suggest that prenylflavonoids from hops have potential for application in cancer prevention programs and in prevention or treatment of (post-)menopausal 'hot flashes' and osteoporosis. Xanthohumol and 8-prenylnaringenin are metabolized into many flavonoid derivatives with modified 3,3-dimethyl allyl (prenyl) moieties. Xanthohumol is formed in lupulin glands by a specialized branch of flavonoid biosynthesis that involves prenylation and O-methylation of the polyketide intermediate chalconaringenin. Although a lupulin gland-specific chalcone synthase is known, the aromatic prenyltransferase and O-methyltransferase participating in xanthohumol have not been identified. The prenylflavonoid pathway is a possible target for breeding or biotechnological modification of hops with the aim of increasing xanthohumol levels for beer brewing and 8-prenylnaringenin levels for pharmaceutical production.

Some aspects of toxic contaminants in herbal medicines.

A World Health Organisation survey indicated that about 70-80% of the world populations rely on non-conventional medicine mainly of herbal sources in their primary healthcare. In recent years, we have witnessed the increasing growth in popularity of over-the-counter (OTC) health foods, nutraceuticals, and medicinal products from plants or other natural sources in developed countries. This indirectly indicates that the public is not satisfied with their orthodox medical (OM) treatment. Such increase in popularity has also brought concerns and fears over the professionalism of practitioners, and quality, efficacy and safety of their treatment methods and products from herbal and natural sources available in the market. Over the past decade several news-catching episodes in developed communities indicated adverse effects, sometimes life threatening, allegedly arisen consequential to taking of OTC herbal products or traditional medicines from various ethnic groups. These OTC products may be contaminated with excessive or banned pesticides, microbial contaminants, heavy metals, chemical toxins, and for adulterated with orthodox drugs. Excessive or banned pesticides, heavy metals and microbial contaminants may be related to the source of these herbal materials, if they are grown under contaminated environment or during collection of these plant materials. Chemical toxins may come from unfavourable or wrong storage conditions or chemical treatment due to storage. The presence of orthodox drugs can be related to unprofessional practice of manufacturers. Some of these environment related factors can be controlled by implementing standard operating procedures (SOP) leading to Good Agricultural Practice (GAP), Good Laboratory Practice (GLP), Good Supply Practice (GSP) and Good Manufacturing Practice (GMP) for producing these medicinal products from herbal or natural sources. The public's belief that herbal and natural products are safer than synthetic medicines can only be ascertained by imposing regulatory standards on these products that should be manufactured using these Good Practices. Using Chinese medicines, as examples, this paper illustrate how advances in chemical and biomedical analysis would help to detect intentional and unintentional toxic contaminants in herbal substances. The paper also summarises how modernization and progress are being carried out to get the best out of Chinese medicines for public healthcare.

Severe congenital lead poisoning in a preterm infant due to a herbal remedy.

A preterm infant born to a woman with chronic lead poisoning was found to have the highest blood lead level recorded for a surviving neonate. Parenteral calcium disodium edetate, but not oral succimer, was effective in reducing the infant's lead burden in the neonatal period. An exposure assessment revealed the mother's long-term ingestion of lead-contaminated herbal tablets as the source.