Antimutagenic properties of fresh-water blue-green algae

Consequences of AphanizomenonFlos-aquae(AFA) extract (Stemtech (TM) ) on metabolic profile of patients with type 2 diabetes

BACKGROUND

Blue- green algae is one of the most nutrient dense foods which is rich in substances that have useful effects on human health. The purpose of this study was to evaluate the effectiveness of a water- soluble extract of the cyanophyta Aphanizomenon Flos-aquae (Stemtech (TM) ) as a functional supplement on CD markers, lipid profile, glucose levels as well as its side effects in Iranian patients with type 2 diabetes.

METHODS

During this randomized, double-blind, placebo-controlled trial 49 type 2 diabetic patients, aged between 20 and 60 years with a HbA1C ≥ 7.5 %, were allocated. Patients were divided into two groups of placebo and treated with an equal ratio 1:1. The subjects in StemtechTM group received one capsule of StemFlo (508 mg) before breakfast and two capsules of StemEnhance (500 mg) after each meal for a period of 12 weeks, and placebo group was instructed to take placebo with the same pattern. During the intervention period, subjects were asked to keep usual diet and prohibited to take any functional foods or dietary supplements. Metabolic panel has been measured as the primary outcome of study at the beginning and end of the intervention period via blood sampling.

RESULTS

Stemtech (TM) supplementation for 12 weeks decreased fasting blood glucose (FBG) and Glycatedhemoglobin (HbA1c). Mean serum chemistry parameters (Triglyceride, Total Cholesterol, LDL, HDL, CRP, AST, ALT, BUN and Creatinine) as well as CD 34(+), IL-6, TNF-α in treated and control groups before and after the study showed no considerable dissimilarities.

CONCLUSION

StemtechTM intervention brought in positive consequence on blood glucose levels in Iranian patients with type 2 diabetes, consequently suggests the Stemtech (TM) as a functional food for the management of diabetes.

Multiplex PCR for the detection of toxigenic cyanobacteria in dietary supplements produced for human consumption

The production of food supplements containing cyanobacteria is a growing worldwide industry. While there have been several reports of health benefits that can be gained from the consumption of these supplements, there have also been a growing number of studies showing the presence of toxins some of which (for example microcystins) are known to affect human health. In this paper, we report a multiplex polymerase chain reaction (PCR) technique that can be used to identify microcystin contamination in dietary supplements produced for human consumption. This method involves a PCR reaction containing three primer pairs, the first of which is used to amplify a 220-bp fragment of 16s rDNA specific to Microcystis, the most common microcystin-producing cyanobacterium. The second primer pair is used to amplify a 300-bp fragment of the mcyA gene, linked to microcystin biosynthesis in Anabaena, Microcystis, and Planktothrix. A third primer pair, used as a positive control, results in the amplification of a 650-bp fragment from the phycocyanin operon common to all cyanobacteria. This technique was found to be useful for detecting the presence of toxigenic Microcystis in all dietary supplements produced from the nontoxic cyanobacterium Aphanizomenon flos-aquae.

Detection of microcystin synthetase genes in health food supplements containing the freshwater cyanobacterium Aphanizomenon flos-aquae

In this study we investigated the presence of toxin-producing cyanobacterial contaminants in food supplements manufactured from blooms of the non-toxic freshwater cyanobacterium Aphanizomenon flos-aquae. Previous reports investigating the contamination of health food supplements with toxin-producing cyanobacteria have used chemical and or biochemical methods such as HPLC, ELISA and protein phosphatase assays. Whilst these studies have drawn attention to the presence of hepatotoxic microcystins in some commercially available food supplements, the methods used do not provide any information on the source of the contaminant. Such information would be useful for the quality control of food supplements produced for human consumption. In this study we applied a molecular technique, involving the amplification of the 16s rRNA gene, the phycocyanin operon, and two genes of the microcystin synthetase gene cluster to show that all 12 food supplement samples, sourced from various internet distributors and containing non-toxic A. flos-aquae, also contained toxigenic cyanobacteria. Sequencing of the microcystin synthetase genes detected in all of the food supplements showed that M. aeruginosa was the organism responsible for the production of microcystins in the samples. The presence of microcystins in the food supplements was confirmed by ELISA, with concentrations within the range of 0.1--4.72 microgg(-1) (microcystin-LR equivalents). Given that the molecular methods applied here are highly sensitive, and show good agreement with the results obtained from ELISA, we believe that they could potentially be used as a quality control technique for food products that contain cyanobacteria.

Risk assessment of microcystin in dietary Aphanizomenon flos-aquae

Aphanizomenon flos-aquae, a cyanobacterium that is marketed as a health food supplement, is harvested from natural blooms in Klamath Lake (Oregon) that are occasionally contaminated by Microcystis spp. Regulatory agencies in several countries are developing regulations to control the amount of microcystin in drinking water and other products, including products produced from A. flos-aquae. Regulation of microcystin (MC), a toxin produced by Microcystis spp. that is potentially present in natural culture of A. flos-aquae, should be based on studies in which a test species is exposed to the natural mixture of these cyanobacteria. A 1984 feeding trial to determine the effects of high dietary levels of A. flos-aquae on reproduction and development of mice is reanalyzed in light of recent analyses for microcystin-LR (MCLR) in the diets of those mice. Young adult mice consuming up to 333 microg MCLR/kg body weight (bw)/day exhibited no adverse effects on growth and reproduction, fetal development, and survival and organ weights of neonates. Based on a NOAEL of 333 microg MCLR/kg bw/day, a safety factor of 1000, consumption of 2 g/day of A. flos-aquae by a 60-kg adult, the safe level of MCLR as a contaminant of A. flos-aquae products is calculated to be 10.0 microg MCLR/g.