Kiwifruit Resistance to Sclerotinia sclerotiorum and Pseudomonas syringae pv. actinidiae and Defence Induction by Acibenzolar-S-methyl and Methyl Jasmonate Are Cultivar Dependent.

Pathogen susceptibility and defence gene inducibility were compared between the Actinidia arguta cultivar 'Hortgem Tahi' and the two cultivars of A. chinensis 'Hayward' and 'Zesy002'. Plants were treated with acibenzolar-s-methyl (ASM) or methyl jasmonate (MeJA) one week before inoculation with Pseudomonas syringae pv. actinidiae (Psa biovar3) or Sclerotinia sclerotiorum, or secondary induction with chitosan+glucan (Ch-Glu) as a potential pathogen proxy. Defence expression was evaluated by measuring the expression of 18 putative defence genes. 'Hortgem Tahi' was highly susceptible to sclerotinia and very resistant to Psa, whereas 'Zesy002' was highly resistant to both, and 'Hayward' was moderately susceptible to both. Gene expression in 'Hayward' and 'Zesy002' was alike but differed significantly from 'Hortgem Tahi' which had higher basal levels of PR1-i, PR5-i, JIH1, NPR3 and WRKY70 but lower expression of RD22 and PR2-i. Treatment with ASM caused upregulation of NIMIN2, PR1-i, WRKY70, DMR6 and PR5-i in all cultivars and induced resistance to Psa in 'Zesy002' and 'Hayward' but decreased resistance to sclerotinia in 'Zesy002'. MeJA application caused upregulation of LOX2 and downregulation of NIMIN2, DMR6 and PR2-i but did not affect disease susceptibility. The Ch-Glu inducer induced PR-gene families in each cultivar, highlighting its possible effectiveness as an alternative to actual pathogen inoculation. The significance of variations in fundamental and inducible gene expression among the cultivars is explored.

Effects of Drought and Flooding on Phytohormones and Abscisic Acid Gene Expression in Kiwifruit.

Environmental extremes, such as drought and flooding, are becoming more common with global warming, resulting in significant crop losses. Understanding the mechanisms underlying the plant water stress response, regulated by the abscisic acid (ABA) pathway, is crucial to building resilience to climate change. Potted kiwifruit plants (two cultivars) were exposed to contrasting watering regimes (water logging and no water). Root and leaf tissues were sampled during the experiments to measure phytohormone levels and expression of ABA pathway genes. ABA increased significantly under drought conditions compared with the control and waterlogged plants. ABA-related gene responses were significantly greater in roots than leaves. ABA responsive genes, DREB2 and WRKY40, showed the greatest upregulation in roots with flooding, and the ABA biosynthesis gene, NCED3, with drought. Two ABA-catabolic genes, CYP707A i and ii were able to differentiate the water stress responses, with upregulation in flooding and downregulation in drought. This study has identified molecular markers and shown that water stress extremes induced strong phytohormone/ABA gene responses in the roots, which are the key site of water stress perception, supporting the theory kiwifruit plants regulate ABA to combat water stress.

Effects of Blackcurrant and Dietary Fibers on Large Intestinal Health Biomarkers in Rats.

This study examined the effects of anthocyanin-rich blackcurrant extract and dietary fibers individually and their combinations on biomarkers of large intestinal health in rats. After six weeks of feeding, rats fed diets with blackcurrant gained significantly less body weight and reduced their food intake resulting in a lower food efficiency compared with those rats fed control diets. Combining dietary fiber (apple or broccoli) with blackcurrant in the diet was more effective in reducing the body weight gain and food intake. Cecal bacterial populations and short-chain fatty acids differed between the experimental diets. Blackcurrants significantly altered the bacterial populations by increasing the abundance of Bacteroides-Prevotella-Porphyromonas group and Lactobacillus spp., while decreasing the abundance of Bifidobacterium spp. and Clostridium perfringens. Propionic acid concentrations were increased by the diets with blackcurrant. Butyric acid concentrations were increased by dietary fiber supplementation. Dietary fiber increased the number of goblet cells in the colon. Diets with blackcurrant were more effective in altering the biomarkers of large intestinal health than those without blackcurrant.

Dietary flavonoids from modified apple reduce inflammation markers and modulate gut microbiota in mice.

Apples are rich in polyphenols, which provide antioxidant properties, mediation of cellular processes such as inflammation, and modulation of gut microbiota. In this study we compared genetically engineered apples with increased flavonoids [myeloblastis transcription factor 10 (MYB10)] with nontransformed apples from the same genotype, "Royal Gala" (RG), and a control diet with no apple. Compared with the RG diet, the MYB10 diet contained elevated concentrations of the flavonoid subclasses anthocyanins, flavanol monomers (epicatechin) and oligomers (procyanidin B2), and flavonols (quercetin glycosides), but other plant secondary metabolites were largely unaltered. We used these apples to investigate the effects of dietary flavonoids on inflammation and gut microbiota in 2 mouse feeding trials. In trial 1, male mice were fed a control diet or diets supplemented with 20% MYB10 apple flesh and peel (MYB-FP) or RG apple flesh and peel (RG-FP) for 7 d. In trial 2, male mice were fed MYB-FP or RG-FP diets or diets supplemented with 20% MYB10 apple flesh or RG apple flesh for 7 or 21 d. In trial 1, the transcription levels of inflammation-linked genes in mice showed decreases of >2-fold for interleukin-2 receptor (Il2rb), chemokine receptor 2 (Ccr2), chemokine ligand 10 (Cxcl10), and chemokine receptor 10 (Ccr10) at 7 d for the MYB-FP diet compared with the RG-FP diet (P < 0.05). In trial 2, the inflammation marker prostaglandin E(2) (PGE(2)) in the plasma of mice fed the MYB-FP diet at 21 d was reduced by 10-fold (P < 0.01) compared with the RG-FP diet. In colonic microbiota, the number of total bacteria for mice fed the MYB-FP diet was 6% higher than for mice fed the control diet at 21 d (P = 0.01). In summary, high-flavonoid apple was associated with decreases in some inflammation markers and changes in gut microbiota when fed to healthy mice.

Detection of non-pathogenic and pathogenic populations of Vibrio parahaemolyticus in various samples by the conventional, quantitative and droplet digital PCRs.

In this study, three generations of polymerase chain reaction (PCR) assays: (i) conventional PCR, (ii) qPCR and (iii) droplet digital PCR (ddPCR), were systematically tested for their abilities to detect non-pathogenic and pathogenic populations of Vibrio parahaemolyticus. The limit of detection (LOD) for the ddPCR was 1.1 pg/µL of purified DNA, followed by the qPCR (5.6 pg/µL) and the conventional PCR (8.8 pg/µL). Regarding the LOD for V. parahaemolyticus cells, the ddPCR assay was able to detect 29 cells, followed by the conventional PCR assay (58 cells) and the qPCR assay (115 cells). Regarding the sensitivities to detect this pathogen from PCR inhibition prone samples (naturally contaminated mussels), the ddPCR assay significantly outperformed the conventional PCR and qPCR. The ddPCR assay was able to consistently detect non-pathogenic and pathogenic populations of V. parahaemolyticus from naturally contaminated mussels, indicating its tolerance to various PCR inhibitors. This study also revealed the significant difference between conventional PCR and qPCR. The conventional PCR assay showed significantly greater sensitivity than that of the qPCR assay in detecting V. parahaemolyticus in crude samples, whereas the qPCR assay showed better sensitivity in detecting the presence of V. parahaemolyticus in purified DNA samples.

High arousal as the source of food rejection in food neophobia.

Food neophobia (FN) at moderate to high levels is very common among adult populations in all cultures and is usually defined in terms of rejection of unfamiliar foods. However, food rejection in FN is only partly related to food familiarity. Experimental and survey studies have suggested that unpleasantly high arousal may be induced by food novelty, but also be produced by foods with intense or complex flavours, that are perceived as dangerous or foreign, or that have unusual ingredients. Liking for foods with these characteristics have recently been shown to be strongly negatively associated with FN. Thus, induced high arousal may underlie food rejection in FN. Here, we collected familiarity, liking and arousal ratings, and scores on the standard Food Neophobia Scale from more than 7000 consumers in four countries - Australia, United Kingdom, Singapore, Malaysia - for a series of food names that were manipulated to produce standard and 'high arousal' (variant) versions of the same foods. Consistent across all four countries, arousal ratings increased, and liking decreased, with decreases in food familiarity. Variant food names were always associated with ratings of higher arousal than the standard names. The variant foods were generally less familiar than the standard foods, although this was not a necessary condition for their higher arousal ratings, suggesting that the other arousal-inducing factors (e.g., flavour intensity) also played a role. Across all foods, arousal ratings increased, and liking ratings decreased, as FN increased, but these effects were accentuated for the variant foods. The consistency of these effects across multiple countries supports a view that arousal is universally a strong determinant of liking for foods and that this underlies the rejection of foods, familiar and novel, in FN.

Postharvest Application of Acibenzolar-S-Methyl Activates Salicylic Acid Pathway Genes in Kiwifruit Vines.

The plant defence inducer Actigard® (acibenzolar-S-methyl [ASM]) is applied before flowering and after fruit harvest to control bacterial canker in kiwifruit caused by Pseudomonas syringae pv. actinidiae. Pre-flowering application of ASM is known to upregulate defence gene expression; however, the effect of postharvest ASM on defence gene expression in the vine is unknown. In this study, the expression of eight "defence marker" genes was measured in the leaves of Actinidia chinensis var. chinensis, "Zesy002," and Actinidia chinensis var. deliciosa, "Hayward," vines after postharvest treatment with ASM and/or copper. There were two orchards per cultivar with harvest dates approximately three weeks apart for investigating potential changes in responsiveness to ASM during the harvest period. In all trials, postharvest ASM induced the expression of salicylic-acid-pathway defence genes PR1, PR2, PR5, BAD, DMR6, NIMIN2, and WRKY70. Gene upregulation was the greatest at 1 day and 7 days after treatment and declined to the control level after 3 weeks. In "Zesy002", the ASM-induced response was greater at the early harvest site than at the late harvest site. This decline was concomitant with leaf yellowing and a reduction in RNA yield. Effects of postharvest ASM on gene expression did not persist into the following spring, nor were vines conditioned to respond more strongly to pre-flowering ASM application.

Microstructure, rheological and water mobility behaviour of plant-based protein isolates (pea and quinoa) and locust bean gum mixtures.

This work reports the impact of locust bean gum (LBG) in the continuous phase of plant-based proteins, i.e. quinoa protein (QPI) and pea protein isolates (PPI). Experimental measurements such as confocal microscopy, rheological analysis and water mobility via nuclear magnetic resonance (nmr) spin-spin relaxation time (T2) were carried out. The influence of LBG on the rheological properties of QPI and PPI is consistent with an exchange-based nmr interpretation of T2 for biopolymer and water. Addition of LBG increased the viscoelastic properties (storage and loss modulus) and shear viscosities of the mixtures. LBG interacted with both plant proteins, resulting in the formation of more dense protein networks and protein coacervates. A stronger interaction between the PPI and LBG was observed, resulting in higher shear viscosities with lower water mobility as compared to QPI:LBG formulations. Results indicated that the interaction between the protein and polysaccharide played a significant role in the microstructure, its rheological properties and consequently water mobility.

Effects of Daily Ingestion of Two SunGold Kiwifruit for 6 Weeks on Metabolic and Inflammatory Biomarkers: A Randomized, Cross-Over, Exploratory Intervention Study.

Kiwifruit contain many components, some considered beneficial, such as vitamins, phytochemicals and dietary fibre, and others potentially harmful, such as fructose and glucose in fruit sugars. In a 6-week, randomised, crossover study aimed at exploring the net effects of daily consumption of kiwifruit, 23 healthy participants consumed two Actinidia chinensis var. chinensis 'Zesy002' (marketed as Zespri™ SunGold™ Kiwifruit) per day as part of their customary diet (intervention) or without kiwifruit (control) as their customary diet for 6 weeks in a cross-over study. Anthropometric data, venous blood, and urine samples were collected at the start and end of the 6-week intervention and control periods for the measurement of physical changes, plasma glucose, insulin, glycated haemoglobin, short-chain fatty acids, blood lipids, uric acid, inflammatory biomarkers, and urinary ascorbic acid. Variables were measured between the start and finish of interventions, and between intervention and control periods. Food diaries were completed on the 3 days before blood sampling to estimate dietary ascorbic acid and dietary fibre intakes. Despite urinary vitamin C and food diaries indicating compliance, and good precision in measurements, there were no appreciable changes in biomarkers during the study, either within or between intervention and control periods, that would indicate a change in health status. Thus, the sizes of any effects of kiwifruit ingestion were too small to become significant under the test conditions used, indicating a high probability that daily ingestion of two SunGold kiwifruit is safe with respect to metabolic health.

Anxiety-like Behavior in Female Sprague Dawley Rats Associated with Cecal Clostridiales.

The relationship between the microbiota profile and exposure to stress is not well understood. Therefore, we used a rat model of unpredictable chronic mild stress (UCMS) to investigate this relationship. Depressive-like behaviors were measured in Female Sprague Dawley rats using the sucrose preference test and the Porsolt swim test. Anxiety-like behaviors were measured with the light-dark box test. Fecal corticosterone, cecal microbiota (composition and organic acids), plasma gut permeability (lipopolysaccharide-binding protein, LBP) and plasma inflammation (12 cytokines) markers were measured. Atypical behaviors were observed in female rats following UCMS, but no depressive-like behaviors were observed. Circulating concentrations of cytokines granulocyte-macrophage colony-stimulating factor and cytokine-induced neutrophil chemoattractant 1 were higher in UCMS-exposed female rats; plasma LBP and cecal organic acid levels remained unchanged. Our results reflect a resilient and adaptive phenotype for female SD rats. The relative abundance of taxa from the Clostridiales order and Desulfovibrionaceae family did, however, correlate both positively and negatively with anxiety-like behaviors and plasma cytokine concentrations, regardless of UCMS exposure, supporting the brain-to-gut influence of mild anxiety with a microbiota profile that may involve inflammatory pathways.

The Efficacy of New Zealand Greenshell™ Mussel Powder Supplementation in Supporting Muscle Recovery Following Eccentric Exercise-Induced Muscle Damage in Healthy, Untrained Adult Males.

Unaccustomed eccentric exercise results in muscle damage limiting physical performance for several days. This study investigated if Greenshell™ mussel (GSM) powder consumption expedited muscle recovery from eccentric exercise-induced muscle damage (EIMD). Methods: Twenty untrained adult men were recruited into a double-blind, placebo-controlled, cross-over study and were randomly assigned to receive the GSM powder or placebo treatment first. Participants consumed their allocated intervention for four weeks then completed a bench-stepping exercise that induced muscle damage to the eccentrically exercised leg. Muscle function, soreness and biomarkers of muscle damage, oxidative stress and inflammation were measured before exercise, immediately after exercise and 24, 48 and 72 h post exercise. GSM powder promoted muscle function recovery, significantly improving (p < 0.05) isometric and concentric peak torque at 48 h and 72 h post exercise, respectively. Participants on the GSM treatment had faster dissipation of soreness, with significant treatment × time interactions for affective (p = 0.007) and Visual Analogue Scale-assessed pain (p = 0.018). At 72 h, plasma creatine kinase concentrations in the GSM group were lower (p < 0.05) compared with the placebo group. This study provides evidence for GSM powder being effective in supporting muscle recovery from EIMD.

Comparative genomics uncovered differences between clinical and environmental populations of Vibrio parahaemolyticus in New Zealand.

Vibrio parahaemolyticus has been identified as an emerging human pathogen worldwide with cases undergoing a global expansion over recent decades in phase with climate change. New Zealand had remained free of outbreaks until 2019, but different outbreaks have been reported consecutively since then. To provide new insights into the recent emergence of cases associated with outbreak clones over recent years, a comparative genomic study was carried out using a selection of clinical (mostly outbreak) and environmental isolates of V. parahaemolyticus obtained in New Zealand between 1973 and 2021. Among 151 isolates of clinical (n=60) and environmental (n=91) origin, 47 sequence types (STs) were identified, including 31 novel STs. The population of environmental isolates generated 30 novel STs, whereas only 1 novel ST (ST2658) was identified among the population of clinical isolates. The novel clinical ST was a single-locus variant of the pandemic ST36 strain, indicating further evolution of this pandemic strain. The environmental isolates exhibited a significant genetic heterogeneity compared to the clinical isolates. The whole-genome phylogeny separated the population of clinical isolates from their environmental counterparts, clearly indicating their distant genetic relatedness. In addition to differences in ancestral profiles and genetic relatedness, these two groups of isolates exhibited a profound difference in their virulence profiles. While the entire population of clinical isolates harboured the thermostable direct haemolysin (tdh) and/or the thermostable-related haemolysin (trh), only a few isolates of environmental origin possessed the same virulence genes. In contrast to tdh and trh, adhesin-encoding genes, vpadF and MSHA, showed a significantly (P<0.001) greater association with the environmental isolates compared to the clinical isolates. The effectors, VopQ, VPA0450 and VopS, which belong to T3SS1, were ubiquitous, being present in each isolate regardless of its origin. The effectors VopC and VopA, which belong to T3SS2, were rarely detected in any of the examined isolates. Our data indicate that the clinical and environmental isolates of V. parahaemolyticus from New Zealand differ in their population structures, ancestral profiles, genetic relatedness and virulence profiles. In addition, we identified numerous unique non-synonymous single-nucleotide polymorphisms (nsSNPs) in adhesins and effectors, exclusively associated with the clinical isolates tested, which may suggest a possible role of these mutations in the overall virulence of the clinical isolates.

Characterizing kiwifruit carbohydrate utilization in vitro and its consequences for human faecal microbiota.

It is well accepted that our gut bacteria have coevolved with us in relation to our genetics, diet and lifestyle and are integrated metabolically with us to affect our gut health adversely or beneficially. "Who is there" may vary quite widely between individuals, as might "how they do it", but "what they make" may be less variable. Many different individual species of bacteria can perform the same saccharolytic functions and so the availability of substrate (host or diet-derived) along with the degradative enzymes they possess may be key drivers of gut ecology. In this case study, we discuss detailed microbial ecology and metabolism analysis for three individuals following 48 h of in vitro faecal fermentation, using green kiwifruit as the substrate. In parallel, we have analyzed the chemical changes to the kiwifruit carbohydrates present in the fermenta to close the circle on substrate usage/degradative enzymes possessed/microbes present/microbial byproducts produced. In the absence of host carbohydrate, we see that kiwifruit carbohydrates were differentially utilized to drive microbial diversity, yet resulted in similar byproduct production. The starting ecology of each individual influenced the quantitative and qualitative microbial changes; but not necessarily the metabolic byproduct production. Thus, we propose that it is the consistent functional changes that are relevant for assessment of gut health benefits of any food. We recommend that in this era of large scale genotype/-omics studies that hypothesis-driven, bottom-up research is best placed to interpret metagenomic data in parallel with functional, phenotypic data.

Effects of alternative label formats on choice of high- and low-sodium products in a New Zealand population sample.

OBJECTIVE: Dietary sodium reduction is a cost-effective public health intervention to reduce chronic disease. In response to calls for further research into front-of-pack labelling systems, we examined how alternative sodium nutrition label formats and nutrition claims influenced consumers' choice behaviour and whether consumers with or without a diagnosis of hypertension differed in their choice patterns. DESIGN: An anonymous online experiment in which participants viewed ten choice sets featuring three fictitious brands of baked beans with varied label formats and nutritional profiles (high and low sodium) and indicated which brand in each set they would purchase if shopping for this product. SETTING: Participants were recruited from New Zealand's largest online nationwide research panel. SUBJECTS: Five hundred people with self-reported hypertension and 191 people without hypertension aged 18 to 79 years. RESULTS: The addition of a front-of-pack label increased both groups' ability to discriminate between products with high and low sodium, while the Traffic Light label enabled better identification of the high-sodium product. Both front-of-pack formats enhanced discrimination in the presence of a reduced salt claim, but the Traffic Light label also performed better than the Percentage Daily Intake label in moderating the effect of the claim for the high-sodium product. CONCLUSIONS: Front-of-pack labels, particularly those with simple visual cues, enhance consumers' ability to discriminate between high- and low-sodium products, even when those products feature nutrition claims.

In vitro utilization of gold and green kiwifruit oligosaccharides by human gut microbial populations.

We examined the effects of whole kiwifruit on gut microbiota using an in vitro batch model of gastric-ileal digestion and colonic fermentation. Faecal fermentations of gold and green kiwifruit, inulin and water (control) digests were performed for up to 48 h. As compared to the control, gold and green kiwifruit increased Bifidobacterium spp. by 0.9 and 0.8 log(10) cfu/ml, respectively (P < 0.001), and the Bacteroides-Prevotella-Porphyromonas group by 0.4 and 0.5 log(10) cfu/ml, respectively. Inulin only had a bifidogenic effect (+0.4 log(10) cfu/ml). This was accompanied with increases in microbial glycosidases, especially those with substrate specificities relating to the breakdown of kiwifruit oligosaccharides, and with increased generation of short chain fatty acids. The microbial metabolic activity was sustained for up to 48 h, which we attribute to the complexity of the carbohydrate substrate provided by whole kiwifruit. Kiwifruit fermenta supernatant was also separately shown to affect the in vitro proliferation of Bifidobacterium longum, and its adhesion to Caco-2 intestinal epithelial cells. Collectively, these data suggest that whole kiwifruit may modulate human gut microbial composition and metabolism to produce metabolites conducive to increased bifidobacteria-host association.

Actinidin diversity: discovery of common and selective substrates for actinidin isoforms and Actinidia cultivars.

The actinidin proteinase family has a striking sequence diversity; isoelectric points range from 3.9 to 9.3. The biological drive for this variation is thought to be actinidin's role as a defense-related protein. In this study we map mutations in the primary sequence onto the 3D structure of the protein and show that the region with the highest diversity is close to the substrate binding groove. Non-conservative substitutions in the active site determine substrate preference and therefore create problems for quantification of actinidin activity. Here we use a peptide substrate library to compare two actinidin isoforms, one from the kiwiberry cultivar 'Hortgem Tahi' (Actinidia arguta), and the other from the familiar kiwifruit cultivar 'Hayward' (Actinidia chinensis var. deliciosa). Among 360 octamer substrates we find one substrate (RVAAGSPI) with the useful property of being readily cleaved by all the functionally active actinidins in a set of A. arguta and A. chinensis var. deliciosa isoforms. In addition, we find that two substrates (LPPKSQPP & ILRDKDNT) have the ability to differentiate different isoforms from a single fruit. We compare actinidins from 'Hayward' and A. arguta for their ability to digest the allergenic gluten peptide (PFPQPQLPY) but find the peptide to be indigestible by all sources of actinidin. The ability to inactivate salivary amylase is shown to be a common trait in Actinidia cultivars due to proteolysis by actinidin and is particularly strong in 'Hortgem Tahi'. A mixture of 10% 'Hortgem Tahi' extract with 90% saliva inactivates 100% of amylase activity within 5 minutes. Conceivably, 'Hortgem Tahi' might lower the glycaemic response in a meal rich in cooked starch.

Dietary Fibre and Organic Acids in Kiwifruit Suppress Glycaemic Response Equally by Delaying Absorption-A Randomised Crossover Human Trial with Parallel Analysis of 13C-Acetate Uptake.

Non-sugar components of kiwifruit reduce the amplitude of the glycaemic response to co-consumed cereal starch. We determined the relative contribution of different non-sugar kiwifruit components to this anti-glycaemic effect. Healthy participants (n = 9) ingested equal carbohydrate meals containing 20 g starch as wheat biscuit (WB, 30 g), and the sugar equivalent of two kiwifruit (KFsug, 20.4 g), either intrinsic or added as glucose, fructose and sucrose (2:2:1). The meals were WB+KFsug (control, no non-sugar kiwifruit components), WB + whole kiwifruit pulp (WB+KF), WB + neutralised kiwifruit pulp (WB+KFneut), WB + low-fibre kiwifruit juice (WB+KFjuice) and WB+KFsug + kiwifruit organic acids (WB+KFsug+OA). All meals were spiked with 100 mg sodium [1-13C] acetate to measure intestinal absorption. Each participant ingested all meals in random order. Blood glucose and breath 13CO2 were measured at ingestion and at 15 min intervals up to 180 min. Compared with WB+KFsug, whole kiwifruit pulp (WB+KF) almost halved glycaemic response amplitude (p < 0.001), reduced incremental area under the blood glucose response curve (iAUC) at 30 min (peak) by 50% (p < 0.001), and averted late postprandial hypoglycaemia. All other treatments suppressed response amplitude half as much as whole kiwifruit and averted acute hypoglycaemia, with little effect on iAUC. Effects on 13CO2 exhalation paralleled effects on blood glucose (R2 = 0.97). Dietary fibre and organic acids contributed equally to the anti-glycaemic effect of kiwifruit by reducing intestinal absorption rate. Kiwifruit flesh effectively attenuates glycaemic response in carbohydrate exchange, as it contains fructose, dietary fibre and organic acids.

Influence of oral administration of kukoamine A on blood pressure in a rat hypertension model.

The benefits of lowering blood pressure (BP) are well established for the prevention of cardiovascular disease. While there are a number of pharmaceuticals available for lowering BP, there is considerable interest in using dietary modifications, lifestyle and behaviour changes as alternative strategies. Kukoamines, caffeic acid derivatives of polyamines present in solanaceous plants, have been reported to reduce BP. We investigated the effect of orally administered synthetic kukoamine A on BP in the Spontaneously Hypertensive Rat (SHR) laboratory animal model of hypertension. Prior to the hypertension study, we determined the safety of the synthetic kukoamine A in a single oral dose (5 or 10 mg kg-1 bodyweight) 14-day observational study in mice. No negative effects of the oral administration of kukoamine A were observed. We subsequently investigated the effect of daily oral doses of kukoamine A (0, 5, 10 mg kg-1 bodyweight) for 35 days using the SHR rat model of hypertension. The normotensive control Wistar Kyoto (WKY) strain was used to provide a baseline for normal BP in rats. We observed no effect of orally administered synthetic kukoamine A on arterial hypertension in this laboratory animal model of hypertension.

Chewing differences in consumers affect the digestion and colonic fermentation outcomes: in vitro studies.

It is important to understand variability in consumer chewing behavior for designing food products that deliver desired functionalities for target consumer segments. In this study, we selected 29 participants, representing the large range of chewing variation we had observed in 142 healthy young adults, and investigated the influence of chewing behavior on gastrointestinal digestion and colonic fermentation, using in vitro models and brown rice as a model food. Chewing behavior measured by video observations and chewing outcome differed widely between participants, resulting in large differences in the digestibility of carbohydrates. Inter-individual differences in chewing behavior and chewing outcome also significantly affected in vitro patterns of microbial composition and the production of organic acid metabolites, resulting from colonic fermentation, which is increasingly recognized to be important for human health. These digestion/fermentation outcomes were largely related with the chewing time per mouthful, proportion of bolus particles bigger than 2 mm and amount of saliva added to the bolus during chewing. No significant relationships were found with other chewing trajectory and oral physiological measures. These results suggest that modification of chewing may be an effective strategy to control blood glucose levels and to shape gut microbiota and their metabolites, without altering diets, and that further in vivo studies are warranted to confirm these in vitro findings.

Haploid and doubled haploid plants from developing male and female gametes of Gentiana triflora.

Protocols were developed for the generation of haploid or doubled haploid plants from developing microspores and ovules of Gentiana triflora. Plant regeneration was achieved using flower buds harvested at the mid to late uninucleate stages of microspore development and then treated at 4°C for 48 h prior to culture. Anthers and ovaries were cultured on modified Nitsch and Nitsch medium supplemented with a combination of naphthoxyacetic acid and benzylaminopurine. The explants either regenerated new plantlets directly or produced callus that regenerated into plantlets upon transfer to basal media supplemented with benzylaminopurine. Among seven genotypes of different ploidy levels used, 0-32.6% of cultured ovary pieces and 0-18.4% of cultured anthers regenerated plants, with all the genotypes responding either through ovary or anther culture. Flow cytometry confirmed that 98% of regenerated plants were either diploid or haploid. Diploid regenerants were shown to be gamete-derived by observing parental band loss using RAPD markers. Haploid plants were propagated on a proliferation medium and then treated with oryzalin for 4 weeks before transfer back to proliferation medium. Most of the resulting plants were diploids. Over 150 independently derived diploidised haploid plants have been deflasked. The protocol has been successfully used to regenerate plants from developing gametes of seven different diploid, triploid and tetraploid G. triflora genotypes.