It is generally considered that consumers have many concerns about the safety of food additives. What are the causes of such anxiety? Many government agencies conduct questionnaire surveys on the safety of foods. According to the results, food additives are often ranked high as possible problems. However, when looking at survey techniques, in many case, options are included in questionnaires which deliberately manipulate answer choices. When I conducted a questionnaire survey on the safety of food additives for university students in different scientific fields, it could be established that around half of the respondents who disliked food additives nevertheless thought them to be necessary. The most frequent reason for distrust was the possibility of carcinogenic potential for humans. When asked about reasons for disliking food additives in terms of safety, many respondents replied that they were taught at junior or high school that food additives are dangerous for human health. At present, there are no food additives approved for use which have carcinogenic properties in Japan. When applying for a permit for food additives, one is approved only after not only safety but also efficacy are ensured and other requirements are complied with. In light of these facts, it is necessary that teachers at junior and high schools communicate correct information on food additives to their students. Additionally, some food manufacturers frequently state in their commercial messages that they “do not use preservatives” in products for which intended purposes of preservatives used should be appropriately included in labels. However, they actually use certain food additives that are not required to be labeled as preservatives, such as glycine and pH adjusters having similar action to preservatives. These commercial messages frequently mislead many consumers into thinking that preservatives must be hazardous to health. Such manufacturers are being far from socially responsible in their commercial messages.

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“Softness” is one of the physical phenomena which can be felt in daily life by the motion of touch. But there are few ways to represent softness objectively because the motion of touch is part of fundamental daily motion and the feeling of touch strictly depends on in dividual differences. A more precise representation of softness is desired as various technologies advance. The approach and application of a measurement system, which is developed in a writer's project for medical and engineering schools, are introduced in this document.

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Despite a remarkable advance in technology in modern society, significant incidents related to food come up every year, and consumers have not developed a complete sense of security yet. Microorganisms account for the majority of the causes of foodborne diseases. Lactic and acetic acid are widely accepted as safe additives. So far, organic acids and their salts have been studied to control microbial pathogens, and have efficiently suppressed the pathogens listed in the Food Sanitation Act in meat products. For example, Miller and Acuff showed that 4 % sodium lactate inhibited the growth of S. Typhimurium, E. coli O157: H7, S. aureus and L. monocytogenes in beef stored at 10 °C for 28 days. In 2014, L. monocytogenes was newly added as one of the pathogens that must be under control for the safety of non-heated meat products in the Food Sanitation Act. L. monocytogenes can be the causative agent of abortion, septicemia, and meningitis. Organic acids and their salts are also effective against listeria. However, there are several points required to use them adequately. First, the antibacterial effect varies depending on the materials surrounding L. monocytogenes. Second, due to differences in handling after treatment with the acid, listeria can develop greater heat resistance than non-treated organisms. This essay provides hints on how to use organic acids for the manufacturing of safer meat products.

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Glycosaminoglycans (GAGs) including chondroitin sulfate (CS), dermatan sulfate (DS), heparin, heparan sulfate and keratan sulfate (KS) are linear, sulfated repeating disaccharide sequences containing hexosamine and uronic acid (or galactose in the case of KS). Among the GAGs, CS shows structural variations, such as sulfation patterns and fucosylation, which are responsible for their physiological functions through CS interaction with CS-binding proteins. Here, we describe our recent studies exploring CS from marine organisms. We found functional CS, including highly sulfated DS, CS-K and CS/KS from dried shark fins, Enteroctopus dofleini and Mactra chinensis, respectively. Interestingly, CS/KS from Mactra chinensis clearly exhibited resistance to degradation by chondroitinase ABC or ACⅡ (at low concentrations) compared with typical CS structures. We summarize the structural analysis of chondroitin sulfate from marine organisms and the effect of it on the neurite outgrowth activities of hippocampal neurons.

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In Japan, regional revitalization is one of the most important issues at present. In order　to achieve regional revitalization, promotion of the local food industry by improving the commercial value of locally produced foods is one effective way. In this review, our trials regarding locally produced foods in Kochi Prefecture based on knowledge transfer from tacit knowledge into explicit knowledge are introduced; we tried to elucidate and verify the food functionality of Goishi tea (antioxidant activity and protective effects against influenza virus infection), Skipjack tuna (anti-fatigue effect), and Chinese leek (anti-Helicobacter pylori activity) which are important regional products in Kochi Prefecture. At the same time, the concept “local production for local consumption leading to local verification” of our study is also introduced in detail.

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“Flora” is a publication which lists all plant taxa in an area and provides much information as a basis for research into plant diversity and conservation of endangered plant species. Despite its importance, there are countries where a “Flora” has not yet been compiled due to cost, time and human resource limitations. Myanmar is one of them.
Zingiberaceae constitute a large monocotyledonous family, distributed mainly in Southeast Asia, including well known economic plants with ornamental, spice, fragrance and medicinal uses. At least 52 genera and 1,578 species have so far been reported. Classification of species in Zingiberaceae is a difficult subject because the plant inventory is not well established in Southeast Asia and morphological identification of flowers is complicated by availability of only dry specimens, and also large variation depending on the environment. Thus cultivation surveys or expeditions into habitats during flowering season are necessary. The biggest problem is that this corresponds to the rainy season in Southeast Asia. Considering these circumstances, we selected the genus Zingiber which is most used in the ginger family for medicinal purposes across the world, although classification of all but the most representative species already finding economical application has not progressed far. Many wild species have also not been studied for chemical components. First we started to collect rhizomes or tubers of Zingiber from Myanmar and 36 identified samples and 10 unidentified were analyzed by UPLC. As result, 6-gingerol, 8-gingerol and 10-gingerol were detected in all samples of Zingiber officinale, but not in Z. montanum, Z. zerumbet and Z.idae. Interestingly, Z. officinale, Z. montanum, Z. zerumbet, Z. idae showed different chromatogram patterns. With all samples taken into account, there were 5 types: A represented by Z. officinale, B represented by Z. montanum , C represented by Z. idae , D represented by Z. zerumbet and E with chromatograms not showing any obvious peaks, these latter including Z. longiligulatum, Z. rubens, Z. flavomaculosum, Z. squarrosum, Z. thorelli, Z. orbiculatum. At present, isolation and identification of characteristic components in B to D type chromatograms are being carried out and differences of species categorized in E type are under analysis.

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Introduction
“Green Odor” emitted by leaves is composed of six unsaturated C6 alcohols and aldehydes with Z- or E double bonds and two saturated compounds. In response to environmental stimuli, neutral fat, phospho- and galacto-lipids in chloroplasts are hydrolyzed by lipolytic acyl hydrolase to yield α-linolenic and linoleic acids. Then, by lipoxygenase and the hydroperoxide lyase, these acids yield (Z)-3-hexenal and n-hexanal via unstable (S)-13-hydroperoxide intermediates. Finally, by alcohol dehydrogenase these aldehydes are reduced to corresponding alcohols. On the other hand, pyrethrin activity is induced by an original blend of “Green Odor” and (E)-β-farnesene and is formed finally by Lipase/Esterase from chrysanthemoyl CoA and pyrethrolone, respectively. Namely, the pyrethrin forming activities are exactly controlled by the blend ratio of “green odor” and the terpene. This unexpected original finding means that the “Green Odor” is a very important messenger of plant origin.

“Green Odor”
This article describes components, biosynthesis and seasonal changes of the green odor. Green odor emitted by leaves is composed of six unsaturated C6-alcohols, -aldehydes with Z- or E-double bond and two saturated compounds. In these homologues, (E)-2- hexenal is named “leaf aldehyde”, whereas (Z)-3- hexenol is referred to as “leaf alcohol”. Leaf aldehyde was found in fresh green leaves of certain bushes by Curtius T. at Heidelberg University in 1912. Meanwhile, Leaf alcohol was found in fresh tea leaves by my teacher Takei S. at Kyoto University in 1933. In 1960 and 71, I found (E)-3- and (E)-2-hexenols and then in 1973 and 81, I found (Z)- and (E)-3-hexenals from fresh tea leaves. These eight compounds are collectively regarded as “Green odor”. Until today I have investigated them from a multi disciplinary approach of organic chemistry, biochemistry, molecular biology, aroma-physiology and -psychology.
At first, in the biosynthetic pathway of green odor it should be noted for the unexpected findings that the precursor of green odor does not possess six carbons, such as glucoses, but eighteen carbons; α-linolenic (1) and linoleic acids (2). In response to various environmental stimuli, neutral fat, phospho- and galacto-lipids in tea chloroplasts are hydrolyzed by lipolytic acylhydrolase to result in (1) and (2). Then, by lipoxygenase (LOX) these acids are converted to unstable (S)-13-hydroperoxide-intermediates. Following that, by hydroperoxide lyase (HPO lyase) the cleavage of the single bond between carbon-12 and -13 of these intermediates results in (Z)-3-hexenal and n-hexanal. By alcohol dehydrogenase these aldehydes are reduced to corresponding alcohols. It should be noted that the pathway from lipids to (Z)-3-hexenal is a one way reaction, whereas the alcohol-aldehyde redox reaction is an equilibrium. By this equilibrium the concentration balance between six unsaturated alcohols and aldehydes should result in induced bioactive function. Particularly, the lipoxygenase reaction passes through the complex stereochemical steps, that is the removal of a H proton from C11 in α-linolenic acid to form an (S)-13-hydroperoxide-intermediate. This stereochemical coordination is left rotation of R1->R2->R3- bound to asymmetric carbon-13. (Z)-3- and (E)-2-hexenals produced by LOX and HPO lyase differ largely by plant species. The enzyme activities in tea leaf homogenate increases from April to July, reaching a maximum, and then decreases in Autumn, resulting in no detection in Winter.
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