Immunomodulatory effects of dietary supplementation with a milk-based wolfberry formulation in healthy elderly: a randomized, double-blind, placebo-controlled trial

Wolfberry (fruit of Lycium barbarum) has been prized for many years in China for its immunomodulatory property and its high specific antioxidant content. However, clear clinical evidence demonstrating the effect of wolfberry dietary supplementation is still lacking. After our earlier report showing that a proprietary milk-based wolfberry formulation (Lacto-Wolfberry) enhances in vivo antigen-specific adaptive immune responses in aged mice, the present study aimed at demonstrating the effect of dietary Lacto-Wolfberry supplementation on immune functions in the elderly, especially vaccine response known to decline with aging. A 3-month randomized, double-blinded, placebo-controlled study was conducted on 150 healthy community-dwelling Chinese elderly (65-70 years old) supplemented with Lacto-Wolfberry or placebo (13.7 grams/day). Immune response to influenza vaccine was assessed in the study, along with inflammatory and physical status. No serious adverse reactions were reported during the trial, neither symptoms of influenza-like infection. No changes in body weight and blood pressure, blood chemistry or cells composition, as well as autoantibodies levels were observed. The subjects receiving Lacto-Wolfberry had significantly higher postvaccination serum influenza-specific immunoglobulin G levels and seroconversion rate, between days 30 and 90, compared with the placebo group. The postvaccination positive rate was greater in the Lacto-Wolfberry group compared to the placebo group, but did not reach statistical significance. Lacto-Wolfberry supplementation had no significant effect on delayed-type hypersensitivity response and inflammatory markers. In conclusion, long-term dietary supplementation with Lacto-Wolfberry in elderly subjects enhances their capacity to respond to antigenic challenge without overaffecting their immune system, supporting a contribution to reinforcing immune defense in this population.

Maternal docosahexaenoic acid feeding protects against impairment of learning and memory and oxidative stress in prenatally stressed rats: possible role of neuronal mitochondria metabolism

AIMS

Docosahexaenoic acid (22:6n-3; DHA) is known to play a critical role in postnatal brain development. However, no study has been performed to investigate its preventive effect on prenatal stress-induced behavioral and molecular alterations in offspring. In the present study, rats were exposed to restraint stress on days 14-20 of pregnancy, three times a day, 2 hours each time; DHA was given at the doses of 100 and 300 mg/kg/day for two weeks.

RESULTS

We showed that prenatal restraint stress caused (1) learning and memory impairment, (2) BDNF mRNA level decrease, (3) oxidative damage to proteins, (4) enhanced expression of nitric oxide synthase and apoptosis, and (5) abnormalities in mitochondrial metabolism that included changes in mitochondrial complexes I-V, and enhancement of expression of proteins involved in mitochondrial fusion/fission (Mfn-1, Mfn-2, Drp-1) and autophagy (Atg3, Atg7, Beclin-1, p-Akt, and p-mTOR) in the hippocampus of offspring.

INNOVATION

Besides the well-known role in child brain development, we reported the novel finding of DHA in protecting prenatal stress-induced cognitive dysfunction involving the modulation of mitochondrial function and dynamics.

CONCLUSION

Maternal feeding of DHA significantly prevented prenatal stress-induced impairment of learning and memory and normalized the biomarkers of oxidative damage, apoptosis, and mitochondrial metabolism in the hippocampus of both male and female offspring. These results suggest that maternal feeding of DHA exerts preventive effects on prenatal stress-induced brain dysfunction and that modulation of mitochondrial metabolism may play critical role in DHA protection.

Assessment of the modulating effects of fructo-oligosaccharides on fecal microbiota using human flora-associated piglets

We first used human flora-associated (HFA) piglets, a significantly improved model for research on human gut microbiota, to study the effects of short-chain fructo-oligosaccharides (scFOS) on the gut bacterial populations. Ten neonatal HFA piglets were assigned to receive basal diets alone or supplemented with scFOS (0.5 g/kg body weight/day) from 1 to 37 days after birth (DAB). The impact of scFOS on the fecal bacterial populations of the piglets before (12 DAB), during (17 DAB), and after (25 and 37 DAB) weaning were monitored by PCR-denaturing gradient gel electrophoresis and real-time quantitative PCR. The Bifidobacterium genus was stimulated consistently, except during weaning, confirming the bifidogenic property of scFOS. At 12 DAB, the Clostridium leptum subgroup was decreased and two unknown Bacteroides-related species were increased; at 25 DAB, the C. leptum subgroup and Subdoligranulum variabile-like species were elevated, whereas one unknown Faecalibacterium-related species was suppressed; and at 37 DAB, the Bacteroides genus was decreased. The results showed that effects of scFOS on non-bifidobacteria varied at different developmental stages of the animals, warranting further investigation into the host-development-related effects of prebiotics on the gut microbiota and the host physiology using the HFA piglets as a model for humans.

A milk-based wolfberry preparation prevents prenatal stress-induced cognitive impairment of offspring rats, and inhibits oxidative damage and mitochondrial dysfunction in vitro

Lycium barbarum (Fructus Lycii, Wolfberry, or Gouqi) belongs to the Solanaceae. The red-colored fruits of L. barbarum have been used for a long time as an ingredient in Chinese cuisine and brewing, and also in traditional Chinese herbal medicine for improving health. However, its effects on cognitive function have not been well studied. In the present study, prevention of a milk-based wolfberry preparation (WP) on cognitive dysfunction was tested in a prenatal stress model with rats and the antioxidant mechanism was tested by in vitro experiments. We found that prenatal stress caused a significant decrease in cognitive function (Morris water maze test) in female offspring. Pretreatment of the mother rats with WP significantly prevented the prenatal stress-induced cognitive dysfunction. In vitro studies showed that WP dose-dependently scavenged hydroxyl and superoxide radicals (determined by an electron spin resonance spectrometric assay), and inhibited FeCl(2)/ascorbic acid-induced dysfunction in brain tissue and tissue mitochondria, including increases in reactive oxygen species and lipid peroxidation and decreases in the activities of complex I, complex II, and glutamate cysteine ligase. These results suggest that dietary supplementation with WP may be an effective strategy for preventing the brain oxidative mitochondrial damage and cognitive dysfunction associated with prenatal stress.

Phytochemical profiles of different mulberry (Morus sp.) species from China

Mulberry is rich in alkaloids, polyphenols, flavonoids, and anthocyanins, which have been suggested to be responsible for health benefits. The concentrations of 1-deoxynojirimycin (DNJ), resveratrol, oxyresveratrol, cyanidin-3-O-beta-glucoside (Cy-3-glu), cyanidin-3-O-beta-rutinoside (Cy-3-rut), and rutin in mulberry juice, fruits, and leaves of 8 species grown in China were examined. It is the first time content determination of DNJ in mulberry juice and oxyresveratrol in mulberry fruits and leaves has been reported. Among the varieties tested, Da 10 (Morus atropurpurea Roxb.) was the most valuable cultivar considering its high content of functional components. Besides, Hetianbaisang (M. alba Linn.), Taiwanguosang (M. atropurpurea Roxb.), Fujian 2 hao (M. alba Linn.), Gaozhoujisang (M. australis Poir.), and Shanxiguosang (M. nigra Linn.) were rich in DNJ, resveratrol, oxyresveratrol, anthocyanins, and flavonoids, respectively. The high contents of functional compounds in mulberry juice, fruits, and leaves implied that they might be potential resources for the development of functional drinks and food.

FT-IR methodology for quality control of arabinogalactan protein (AGP) extracted from green tea (Camellia sinensis )

A rapid methodology of quality control was developed for arabinogalactan proteins (AGP) extracted and purified from green tea. Using the vectorial angle method and IR spectrum analysis, the 1200-800 cm(-1) region in second-derivative IR spectra was determined as the key fingerprinting region of green tea AGP, with the 1090-900 cm(-1) region reflecting their conservative and common characteristics. In fact, the key monosaccharides, galactose (Gal) and arabinose (Ara), were shown to have intense peaks at about 1075 and 1045 cm(-1), respectively, and uronic acids at about 1018 cm(-1) in second-derivative IR spectra. The variable region was identified to be at about 1134-1094 and 900-819 cm(-1) and was probably due to compositional and structural differences between AGPs. The constructed methodology was tested on green tea AGP extracted by three treatments and purified to apparent homogeneity as water-extracted Camellia sinensis AGP (CSW-AGP), pectinase-extracted C. sinensis AGP (CSP-AGP), and trypsin-extracted C. sinensis AGP (CST-AGP) with an Ara/Gal ratio of 1.37, 1.57, and 1.82, respectively. Regarding in vitro antioxidant activity, the AGPs (CSW-AGP and CST-AGP) with higher similarity (closer cos theta values calculated for second-derivative IR spectra) exhibited a similar ability of chelating ferrous ions and had a similar capability for scavenging hydroxyl radicals. In conclusion, the combination of second-derivative IR spectrum analysis and the vectorial angle method has allowed a successful characterization of green tea AGPs and was shown to be suitable for their compositional and activity discrimination and rapid quality evaluation.

Effects of soluble tea polysaccharides on hyperglycemia in alloxan-diabetic mice

The effects of tea water extracts (TWE), crude tea polysaccharides (CTP), and a tea polysaccharide fraction (TPF) were tested on hyperglycemic diabetic mice. Results indicated that TWE, CTP, and TPF could significantly decrease fasting blood glucose (FBG) and glucosylated serum protein (GSP) in alloxan-induced diabetic mice compared to the control group. In vitro antioxidant activities of TWE, CTP, and TPF for scavenging hydroxyl radicals and superoxide radicals decreased with the degree of purification and were lowest for TPF. High-performance gel permeation chromatography (HPGPC) and component analysis revealed the molecular mass distribution and constituents of TWE, CTP, and TPF, indicating that a 100-120 kDa fraction contained the hypoglycemic activity. This fraction was essentially composed of polysaccharides (approximately 90%) with substantial amounts of arabinogalactan proteins. The second-derivative IR spectra of TWE, CTP, and TPF with peak intensity around 1075 and 1045 cm(-1), which characterize galactopyranose in the backbone and arabinofuranose units in side branches, respectively, further substantiated the importance of the arabinogalactan proteins. Taken together, the results indicate that a soluble tea polysaccharide is the major hypoglycemic factor in tea and that this polysaccharide may be developed to a potential natural hypoglycemic functional ingredient.

Enhanced bioavailability of zeaxanthin in a milk-based formulation of wolfberry (Gou Qi Zi; Fructus barbarum L.)

The carotenoid zeaxanthin is concentrated within the macula. Increased macular zeaxanthin is suggested to lower the risk of age-related macular degeneration. The small red berry, wolfberry (Fructus barbarum L.; Gou Qi Zi and Kei Tze), is one of the richest natural sources of zeaxanthin. However, carotenoid bioavailability is low, and food-based products with enhanced bioavailability are of interest. The present study investigated zeaxanthin bioavailability from three wolfberry formulations. Berries were homogenised in hot (80 degrees C) water, warm (40 degrees C) skimmed milk and hot (80 degrees C) skimmed milk, with freeze drying of each preparation into a powdered form. A zeaxanthin-standardised dose (15 mg) of each was consumed, in randomised order, together with a standardised breakfast by twelve healthy, consenting subjects in a cross-over trial, with a 3-5-week washout period between treatments. Blood samples were taken via a venous cannula immediately before (fasting) and 2, 4, 6, 7, 8 and 10 h post-ingestion. Zeaxanthin concentration in the triacylglycerol-rich lipoprotein fraction of plasma was measured by HPLC. Results showed that triacylglycerol-rich lipoprotein zeaxanthin peaked at 6 h post-ingestion for all formulations. Zeaxanthin bioavailability from the hot milk formulation was significantly higher (P < 0.001) than from the others. Mean area under the curve (n 12) results were 9.73 (sem 2.45), 3.24 (sem 0.72) and 3.14 (sem 1.09) nmol x h/l for the hot milk, warm milk and hot water formulations, respectively. Results showed clearly that homogenisation of wolfberry in hot skimmed milk results in a formulation that has a 3-fold enhanced bioavailability of zeaxanthin compared with both the 'classical' hot water and warm skimmed milk treatment of the berries.

Citrus flavonoids in fruit and traditional Chinese medicinal food ingredients in China

Flavonoids-enriched tissues of citrus such as peel, immature fruit and flower are consumed as culinary seasonings, tea ingredients in China for centuries. This HPLC quantitative study on the five citrus flavonoids, naringin, hesperidin, neohesperidin, sinensetin and nobiletin on a wide range of Chinese citrus fruits and several Traditional Chinese Medicinal food ingredients in East China, revealed a great diversity in flavonoid composition. Huyou peel (C. paradisi cv. Changshanhuyou) was found to be the best naringin (3.25%) and neohesperidin (2.76%) source; C. aurantium, a major ingredient of several citrus-related TCM, is also a suitable source of naringin and neohesperidin, and a good juice source for flavanone glycosides; the peel of Wenzhoumiju (C. unshiu) is one of the richest local species in hesperidin (up to 6.25%); Zaoju (C. subcompressa) has the highest content of nobiletin (0.59%), a polymethoxylated flavone. LC-ES-MS analysis of Zanthoxylum genus for flavonoids revealed for the first time the presence of significant amounts (0.74%) of hesperidin in the root of Liangmianzhen (Z. nitidum (Roxb.) DC), a relative of Sichuan pepper, which is a spice widely used in China.

Molecular and biochemical characterisation of two aspartic proteinases TcAP1 and TcAP2 from Theobroma cacao seeds

Aspartic proteinase (EC 3.4.23) activity plays a pivotal role in the degradation of Theobroma cacao L. seed proteins during the fermentation step of cacao bean processing. Therefore, this enzyme is believed to be critical for the formation of the peptide and amino acid cocoa flavor precursors that occurs during fermentation. Using cDNA cloning and northern blot analysis, we show here that there are at least two distinct aspartic proteinase genes ( TcAP1 and TcAP2) expressed during cacao seed development. Both genes are expressed early during seed development and their mRNA levels decrease towards the end of seed maturation. TcAP2 is expressed at a much higher level than TcAP1, although the expression of TcAP1 increases slightly during germination. The proteins encoded by TcAP1 and TcAP2 are relatively different from each other (73% identity). This, and the fact that the two corresponding genes have different expression patterns, suggests that the TcAP1 and TcAP2 proteins may have different functions in the maturing seeds and during germination. Because the TcAP2 gene is expressed at a much higher level during seed development than TcAP1, it is likely that the TcAP2 protein is primarily responsible for the majority of the industrially important protein hydrolysis that occurs during cacao bean fermentation. Finally, TcAP2 has been functionally expressed in the yeast Yarrowia lipolytica. The secreted recombinant protein is able to hydrolyse bovine haemoglobin at acidic pH and is sensitive to pepstatin A, confirming that TcAP2 encodes an aspartic proteinase, and strongly suggests that this gene encodes the well-characterized aspartic proteinase of mature cacao seeds.

Research on the origin, and on the impact of post-harvest handling and manufacturing on the presence of ochratoxin A in coffee

The major risk factors and processing steps that can lead to contamination of green coffee with ochratoxin A (OTA) have been identified. Surveys of the green coffee production chain indicate that Aspergillus ochraceus and A. carbonarius are the most potent OTA producers on coffee. Both have been successfully grown in vitro on green coffee and coffee cherries, respectively, producing high amounts of OTA (5-13 mg kg(-1)). The so-called dry processing of coffee, which is cherry drying, was identified as one of the steps during which OTA formation can take place, particularly under humid tropical conditions. Cherries contain sufficient amounts of water to support mould growth and OTA formation during the initial 3-5 days of drying on the outer part of the cherries. Not surprisingly, after dehulling, husks can be highly contaminated with OTA, as also indicated by its enhanced concentration in soluble coffees adulterated with husks and parchment. A minimum water activity of 0.80 (about 14% MC) is required for in vitro OTA production on green coffee, a fact that does not rule out the possibility of OTA contamination due to improper transportation and storage of green coffee. However, this appears not to be a major route for OTA contamination of coffee. OTA contamination can clearly be minimized by following good agricultural practice and a subsequent post-harvest handling consisting of appropriate techniques for drying, grading, transportation and storage of green coffee; these procedures are well established.

Chemical composition and flavor of ecuadorian cocoa liquor

The contribution of the chemical composition to the flavor of cocoa liquor from an Ecuadorian selfed population of clone EET 95 was investigated. Polyphenols, purine alkaloids, organic acids, and sugars were quantified, and the key sensory characteristics of cocoa were scored by a trained panel. Despite the short bean fermentation (2 days) commonly used for Arriba cocoa, acetic acid content was closely correlated to liquor pH, demonstrating its essential role in cocoa liquor acidification. Polyphenols were positively correlated to astringency, bitterness, and the green note and negatively correlated to the fruity character. Alkaloid and polyphenol levels fluctuated significantly within the selfed progeny and tended to be lower than those of the heterozygous clone EET 95 (inbreeding effect). These results support the idea that polyphenols might be essential to the overall perception of cocoa liquor characteristics and indicate that the composition and the sensory quality of cocoa liquor are the result of both a genotypic contribution and the conditions of fermentation and roasting.

Developmental variation of sugars, carboxylic acids, purine alkaloids, fatty acids, and endoproteinase activity during maturation of Theobroma cacao L. seeds

The changes of mono- and oligosaccharides, carboxylic acids, purine alkaloids, and fatty acid composition, and of aspartic endoproteinase activity, were analyzed during seed development in two varieties of cacao (Theobroma cacao). The majority of the components examined either decreased or accumulated steadily in concentration during the second half of bean development. Sucrose is the major sugar in the mature embryo, whereas fructose and glucose are at higher concentrations in the endosperm tissue. Considerable amounts of malate are found in the endosperm, whereas citrate is the dominant carboxylic acid in the embryo. A major change in the fatty acid composition occurs in the young embryo when the proportion of stearic acid increases rapidly at the expense of linoleic acid, which is reduced from about 18 to 3%. Theobromine is the dominant purine alkaloid (ca. 80%), and caffeine appears only toward the end of seed maturity. Aspartic endoproteinase activity increases rapidly during embryo expansion, reaching a maximal activity before final maturity. The results are discussed in conjunction with physiological changes in developing seeds, and the potential contributions of the compounds analyzed for cocoa quality.

Production of ochratoxin A by Aspergillus carbonarius on coffee cherries

Robusta coffee cherries collected before and during sun drying from two coffee farms in Thailand were examined for moulds producing ochratoxin A (OA). Aspergillus ochraceus was only detected in one sample, whereas Aspergillus carbonarius was isolated from 7 out of 14 samples. On gamma-irradiated coffee cherries, each of the six tested A. carbonarius strains produced OA. More than 4800 microg kg(-1) of toxin were detected under optimal conditions (25 degrees C, a(w) 0.99). OA production was strongly reduced (230 microg kg(-1)) at an a(w) of 0.94.

Development of ochratoxin A during robusta (Coffea canephora) coffee cherry drying

The occurrence and formation of ochratoxin A (OTA) in Robusta coffee was studied for three consecutive seasons under tropical conditions in Thailand. Sun drying of coffee cherries consistently led to OTA formation in the pulp and parchment (husks) of the cherries. In replicated trials, dried coffee beans (green coffee) were shown to contain on average OTA concentrations that were approximately 1% of those found in husks. OTA contamination of green coffee depended on cherry maturity, with green cherries being the least, and overripe cherries the most susceptible. Defects, and in particular the inclusion of husks, are the most important source of OTA contamination. OTA contamination occurred independently of whether cherries were placed on concrete, on bamboo tables, or on the ground. The study suggests that better raw material quality, an appropriate drying and dehulling procedure combined with a reduction of green coffee defects can effectively contribute to the reduction of OTA in green coffee.

Definition of nonvolatile markers for flavor of tomato (Lycopersicon esculentum mill.) as tools in selection and breeding

A methodology for flavor and composition assessment of processed tomato juice samples was developed using a wide range of commercial processing tomato varieties (Lycopersicon esculentum) grown in Spain and the United States. Fruitiness intensity was found by a trained panel to best describe overall tomato flavor. For two consecutive years, fruitiness intensity was significantly dependent on growing location and variety, and it was consistently linked to increased levels of glucose and reducing sugars and decreased glutamic acid content. Using the same procedure on a population of 176 breeding lines derived from the wild species of Lycopersicon pimpinellifolium, it was shown that tomato fruitiness intensity was significantly correlated to reducing sugars/glutamic acid ratio and glucose and glutamic acid contents. The definition of markers for tomato flavor of processed juice can provide the tomato breeder and processor with reliable analytical tools that can be applied in a straightforward way for the identification of raw materials that can be processed into juice with predictably high or low fruitiness.

Total fecal incontinence--a new method of gluteus maximus transposition: preliminary results and report of previous experience with similar procedures

Since 1986, different procedures of gluteus maximus transposition have been performed, by one of the authors, in 10 patients with total anal incontinence not amenable to sphincter repair, due to congenital anomalies (four), sphincteric denervation (three) or after severe trauma (three). Variable degrees of long-lasting fecal control were obtained in all but one patient, with great improvement in six. Difficulties for achieving a closed anus without muscular tension of the neosphincter, together with the morbidity associated with anal wound infection, determined the reasons for the successive use of different techniques (Biström, Hentz, Schoamaker) until the authors, in 1990, designed a new procedure (Devesa). Although the reported experience with this technique described here is limited to only four patients, our impression is that the method is easier, has less morbidity, and achieves better short-term functional results, derived from a thick, tension-free neosphincter.

β-Glucanases in developing cotton (Gossypium hirsutum L.) fibres

Cotton fibres possess several β-glucanase activities which appear to be associated with the cell wall, but which can be partially solubilised in buffers. The main activity detected was that of an exo-(1→3)-β-D-glucanase (EC 3.2.1.58) but which also had the characteristics of a β-glucosidase (EC 3.2.1.21). Endo-(1→3)-β-D-glucanase activity (EC 3.2.1.39) and much lower levels of (1→4)-β-D-glucanase activity were also detected. The exo-(1→3)-β-glucanase showed a maximum late on (40 days post-anthesis) in the development of the fibres, whereas the endo-(1→3)-β-glucanase activity remained constant throughout fibre development. The β-glucanase complex associated with the cotton-fibre cell wall also functions as a transglucosylase introducing, inter alia, (1→6)-β-glucosyl linkages into the disaccharide cellobiose to give the trisaccharide 4-O-β-gentiobiosylglucose.