食用色素对菊花的染色效应

探讨6种食用色素对菊花的染色效应。结果表明,菊花对亮兰、柠檬黄适应性较好,其次为胭脂红、苋菜红,对葡萄紫、牛奶巧克力棕适应性较差。不同食用色素适宜的染色浓度和染色时间分别为亮蓝(6g/L、4h)、柠檬黄(6g/L、4h),胭脂红(12g/L、6h),苋菜红(9g/L、6h),葡萄紫(20g/L、8h),牛奶巧克力棕(20g/L、8h);适宜的pH值分别为6.6,10.9,10.9,10.2,10.3,10.4。切花开放程度大时染色速度快,花枝去叶与否对染色效果影响不明显。染色后的菊花瓶插寿命显著缩短,但能达到切花所要求的5~7d的观赏期。     

The evaluation of the genotoxicity of two commonly used food colors: Quinoline Yellow (E 104) and Brilliant Black BN (E 151)

Additives, especially colors, are in widespread use in the food industry. With the exception of the quinolines, food colors are relatively weak mutagens and are certified as safe additives despite reports that some people have allergic reactions to them. The number of food additives is still on the increase, and research on their potential mutagenic/carcinogenic activity in vivo is very expensive. Using two different cellular model systems, human lymphocytes in vitro and Vicia faba root tip meristems of in vivo, we evaluated the potential cytological and genotoxic effects of two dyes: Quinoline Yellow (E 104) and Brilliant Black BN (E 151). Two relatively new, very sensitive and rapid tests - the micronucleus and Comet assays - were used in this study. The data provided in this paper showed the genotoxic effects of the two analyzed food colors, and confirmed the diagnostic value of the MN and Comet assays for screening potentially genotoxic substances.     

Decolorization potential of mixed microbial consortia for reactive and disperse textile dyestuffs

Four different aerobic mixed consortia collected from basins of wastewater streams coming out of dying plants of Crescent Textile (CT), Sitara Textile (ST), Chenab Fabrics (CF) and Noor Fatima Textile (NF), Faisalabad, Pakistan were applied for decolorization of Drimarene Orange K-GL, Drimarene Brilliant Red K-4BL, Foron Yellow SE4G and Foron Blue RDGLN for 10 days using the shake flask technique. CT culture showed the best decolorization potential on all dyestuffs followed by ST, NF and CF, respectively. CT could completely decolorize all dyes within 3–5 days. ST cultures showed effective decolorization potential on Foron Yellow SE4G and Drimarene Brilliant Red K-4BL but complete color removal was achieved after 4 and 7 days, respectively. NF culture showed 100% decolorization efficiencies on Foron Yellow SE4G and Foron Blue RDGLN but it took comparatively longer time periods (5–7 days). Where as, the NF culture had decolorized only 40% and 50% of Drimarene orange and red, respectively, after 10 days. CF caused complete decolorization of Foron Blue RDGLN and Drimarene Brilliant Red K-4BL after 4 and 8 days, respectively but it showed poor performance on other two dyes.     

The comet assay with 8 mouse organs: results with 39 currently used food additives

We determined the genotoxicity of 39 chemicals currently in use as food additives. They fell into six categories-dyes, color fixatives and preservatives, preservatives, antioxidants, fungicides, and sweeteners. We tested groups of four male ddY mice once orally with each additive at up to 0.5xLD(50) or the limit dose (2000mg/kg) and performed the comet assay on the glandular stomach, colon, liver, kidney, urinary bladder, lung, brain, and bone marrow 3 and 24h after treatment. Of all the additives, dyes were the most genotoxic. Amaranth, Allura Red, New Coccine, Tartrazine, Erythrosine, Phloxine, and Rose Bengal induced dose-related DNA damage in the glandular stomach, colon, and/or urinary bladder. All seven dyes induced DNA damage in the gastrointestinal organs at a low dose (10 or 100mg/kg). Among them, Amaranth, Allura Red, New Coccine, and Tartrazine induced DNA damage in the colon at close to the acceptable daily intakes (ADIs). Two antioxidants (butylated hydroxyanisole (BHA) and butylated hydroxytoluene (BHT)), three fungicides (biphenyl, sodium o-phenylphenol, and thiabendazole), and four sweeteners (sodium cyclamate, saccharin, sodium saccharin, and sucralose) also induced DNA damage in gastrointestinal organs. Based on these results, we believe that more extensive assessment of food additives in current use is warranted.     

Isolation of a component from commercial coomassie brilliant blue R-250 that stains rubrophilin and other proteins red on polyacrylamide gels

Commercially available Coomassie Brilliant Blue R-250 (C.I. 42660) is a popular and useful dye that stains most proteins blue on polyacrylamide gels. Some proteins from brain (rubrophilin), collagens, histones and parotid gland proteins are distinctly red when stained with Coomassie Blue. Commonly used Coomassie Brilliant Blue R-250 preparations may contain more than 30 distinct colored and fluorescent components that can be separated on silica gel chromatographic columns. A specific component has been isolated on silica gel columns that stains rubrophilin and other proline-rich proteins a reddish color. Fast atom bombardment mass spectrometry of the isolated rubrophilin staining principle indicates a molecular weight of 634 as compared to 826 for the major dye in the original Coomassie Brilliant Blue R-250. Infrared spectrometry is consistent with a difference between the rubrophilin staining principle and Coomassie Brilliant Blue R-250 of a toluene sulfonic acid residue.     

Decolorization of Some Reactive Textile Dyes by White Rot Fungi Isolated in Pakistan

Summary Four white-rot fungi isolated in Pakistan were used for decolorization of widely used reactive textile dyestuffs. Phanerochaete chrysosporium, Coriolus versicolor, Ganoderma lucidum and Pleurotus ostreatus were grown in defined nutrient media for decolorization of Drimarene Orange K-GL, Remazol Brilliant Yellow 3GL, Procion BluePX-5R and Cibacron Blue P-3RGR for 10 days in shake flasks. Samples were removed every day, centrifuged and the absorbances of the supernatants were read to determine percentage decolorization. It was observed that P. chrysosporium and C. versicolor could effectively decolorize Remazol Brilliant Yellow 3GL, Procion BluePX-5R and Cibacron Blue P-3RGR. Drimarene Orange K-GL was completely decolorized (0.2 g/l after 8 days) only by P.chrysosporium, followed by P. ostreatus (0.17 g/l after 10 days). P. ostreatus also showed good decolorization efficiencies (0.19–0.2 g/l) on all dyes except Remazol Brilliant Yellow (0.07 g/l after 10 days). G. lucidum did not decolorize any of the dyestuffs to an appreciable extent except Remazol Brilliant Yellow (0.2 g/l after 8 days).     

Decolorization of Textile Reactive Dyes by Bacterial Monoculture and Consortium Screened from Textile Dyeing Effluent

Dyeing effluents have become a vital source of water pollution. Due to the xenobiotic properties and toxicity to all life forms including humans, removal of undesirable color and associated toxicity is crucial. In this study, five dye decolorizing bacteria were isolated from dyeing effluent using selective enrichment culture in Bushnell-Haas (BH) medium amended with co-substrate (i.e. glucose, yeast extract) and 100?mg?L^?1 of each commercially available reactive dyes viz. Novacron Orange FN-R, Novacron Brilliant Blue FN-R, Novacron Super Black G, Bezema Yellow S8-G and Bezema Red S2-B. The isolated bacteria were identified and assigned as Neisseria sp., Vibrio sp., Bacillus sp., Bacillus sp. and Aeromonas sp. based on their phenotypic (cultural, morphological, physiological and biochemical characteristic) observation. The dye decolorization efficiency was estimated spectrophotometrically up to 6?days of static incubation at 37?°C and observed that all of the isolates were unable to induce decolorization in absence of co-substrate. In case of monoculture, decolorization percentage varies from no visible decolorization (Bezema Red S2-B by Ek-5) to highest 90% decolorization (Novacron Brilliant Blue FN-R by Ek-13) whereas the decolorization percentage of bacterial consortium varies from 65% (Bezema Yellow S8-G) to 90% (Novacron Brilliant Blue FN-R and Novacron Super Black G). The study outlines the co-substrates mediated decolorization process where bacterial consortium proved as efficient dye decolorizer than that of the monocultures. This finding confers possibility of using novel microbial consortium for biological treatment of disreputable dyeing effluents.     

Lack of awareness among future medical professionals about the risk of consuming hidden phosphate-containing processed food and drinks

Phosphate toxicity is an important determinant of mortality in patients with chronic kidney disease (CKD), particularly those undergoing hemodialysis treatments. CKD patients are advised to take a low phosphate-containing diet, and are additionally prescribed with phosphate-lowering drugs. Since these patients usually seek guidance from their physicians and nurses for their dietary options, we conducted a survey to determine the levels of awareness regarding the high phosphate content in commercially processed food and drinks among medical and nursing students at the Hirosaki University School of Medicine in Japan. For this survey, 190 medical and nursing students (average age 21.7±3 years) were randomly selected, and provided with a list of questions aimed at evaluating their awareness of food and drinks containing artificially added phosphate ingredients. While 98.9% of these students were aware of the presence of sugar in commercially available soda drinks, only 6.9% were aware of the presence of phosphate (phosphoric acid). Similarly, only 11.6% of these students were aware of the presence of phosphate in commercially processed food, such as hamburgers and pizza. Moreover, around two thirds of the surveyed students (67.7%) were unaware of the harmful effects of unrestricted consumption of phosphate-containing food and drinks. About 28% of the surveyed students consume such "fast food" once a week, while 40% drink at least 1～5 cans of soda drinks/week. After realizing the potential long-term risks of consuming excessive phosphate-containing food and drinks, 40.5% of the survey participants considered reducing their phosphate intake by minimizing the consumption of commercially processed "fast food" items and soda drinks. Moreover, another 48.4% of students showed interest in obtaining more information on the negative health effects of consuming excessive amounts of phosphate. This survey emphasizes the need for educational initiative to raise awareness of the health risks posed by excessive consumption of phosphate additives.     

Food grade titanium dioxide disrupts intestinal brush border microvilli in vitro independent of sedimentation

Bulk- and nano-scale titanium dioxide (TiO₂) has found use in human food products for controlling color, texture, and moisture. Once ingested, and because of their small size, nano-scale TiO₂ can interact with a number of epithelia that line the human gastrointestinal tract. One such epithelium responsible for nutrient absorption is the small intestine, whose constituent cells contain microvilli to increase the total surface area of the gut. Using a combination of scanning and transmission electron microscopy it was found that food grade TiO₂ (E171 food additive coded) included ～25 % of the TiO₂ as nanoparticles (NPs; <100 nm), and disrupted the normal organization of the microvilli as a consequence of TiO₂ sedimentation. It was found that TiO₂ isolated from the candy coating of chewing gum and a commercially available TiO₂ food grade additive samples were of the anatase crystal structure. Exposure to food grade TiO₂ additives, containing nanoparticles, at the lowest concentration tested within this experimental paradigm to date at 350 ng/mL (i.e., 100 ng/cm² cell surface area) resulted in disruption of the brush border. Through the use of two independent techniques to remove the effects of gravity, and subsequent TiO₂ sedimentation, it was found that disruption of the microvilli was independent of sedimentation. These data indicate that food grade TiO₂ exposure resulted in the loss of microvilli from the Caco-2_BBe1 cell system due to a biological response, and not simply a physical artifact of in vitro exposure.     

Angiotensin II (AII)-related idiotypic network. II. Heterogeneity and fine specificity of AII internal images analyzed with monoclonal antibodies

Although the structural basis of internal images borne by beta type monoclonal anti-idiotypic antibody (Ab2) begins to be elucidated, there is little information on the repertoire of epitopes which make up the internal images expressed by polyclonal Ab2. We addressed this question by using a two-way approach in the angiotensin II (AII)-related idiotypic network, a system characterized by common occurrence of internal images on rabbit Ab2. First, two sets of internal images were purified in parallel by affinity chromatography on Sepharose 4B covalently linked to either mAb 110 (S4B-110), a mAb specific for a phenylalanine requiring carboxy terminus epitope (Phe8) on AII, or mAb 133 (S4B-133), reactive with a more central epitope also expressed on Phe8 substituted peptide analogs. The respective eluates, EL1 110 and E11 133, exhibited only partially overlapping reactivity, as demonstrated by 1) a different pattern of inhibition by various AII peptide analogues of EL1 110 and E11 133 binding to the same anti-AII antibody (Ab1) (either the homologous polyclonal Ab1 102 or mAb 133), 2) and a distinct profile of EL1 110 and EL1 133 binding to 12 biotinylated monoclonal Ab1 identifying a variety of epitopes on AII. To analyze further the respective distribution of mAb 110 and mAb 133 defined epitopes on Ab2-beta molecules, Ab2 were submitted to sequential affinity chromatography on S4B-110 followed by S4B-133, and the fractionated internal images were characterized by the pattern of binding to the various monoclonal Ab1. It was thus possible to purify two Ab2-beta subpopulations that exclusively imaged the determinant identified by mAb 110 (ii 110) or that identified by mAb 133 (ii 133). A third subpopulation which was successively retained on S4B-110 and S4B-133 expressed both internal images (ii 110 + 133), and was additionally reactive with all the other monoclonal Ab1 tested. In any case, monoclonal Ab1 binding to the different sets of internal images was totally inhibited by an excess of AII. These results indicate that the repertoire of internal epitopes is similar to that of the nominal Ag, but is scattered over distinct subpopulations of Ab2-beta molecules that can be fractionated by affinity chromatography. Some of the latter seem to bear several epitopes and resemble the whole nominal Ag, whereas others appear to image only one determinant. Second, we raised 7 anti-anti-idiotypic mAb (monoclonal Ab3) against affinity-purified Ab2-beta and analyzed their fine specificity for AII.(ABSTRACT TRUNCATED AT 400 WORDS)     

Polysaccharides and food processing

The rôle of polysaccharides during processing and for the quality of foods is discussed. Starch is the most important energy source for man. Most other polysaccharides are not metabolized for energy, but play an important rôle as dietary fibres. Pectins, alginates, carrageenans, and galactomannans are discussed as functional food additives in relation to their structure and their rheological behaviour, stability and interactions. Endogenous polysaccharides of fruits and vegetables and in products derived from them are responsible for such phenomena as texture (changes), press yields, ease of filtration and clarification, cloud stability, and mouth feel. To achieve desirable properties, the action of endogenous enzymes on polysaccharides must be inactivated and/or exogenous enzymes added as processing aids. This is also true for overcoming haze phenomena in clear juices or to break down undesirable microbial polysaccharides. Dough properties for bread baking can be improved by enzymic breakdown of a restrictive pentoglycan network. Network formation may come about by oxidative coupling of phenol rings of ferulic acid bound to hemicelluloses by ester links. Gels may be made by inducing oxidative coupling in natural or synthetic systems. Stagnation in development of new polysaccharide food additives is ascribed to difficulties in obtaining government approval for food use.     

Factors affecting food comminution during chewing in ruminants: a review

A review is presented of the chewing effectiveness of herbivorous mammals dealing with the relationship between food comminution (i.e. reduction of particle size), morphological features of teeth, chewing behaviour (i.e. time spent chewing and chewing rate), and the chemical and physical properties of plant tissues. Chewing is the main food processing mechanism in herbivores, increasing the surface/volume ratio of the food, which is a key factor affecting the efficiency of digestion and, therefore, body condition, reproductive success and life history. Chewing effectiveness (CE) is defined as the reduction of a pre-determined amount and particle size of a given food after a known, but not necessarily determined, number of chews. The two main animal-centred factors influencing CE are tooth effectiveness and chewing behaviour. The most frequently used predictors of tooth effectiveness are molar occlusal surface area, molar occlusal contact area (defined as any surface of the upper and lower teeth in or near contact during occlusion) and the length of the enamel cutting edges of the occlusal surface. There is expected to be a direct positive relationship between the predictors of tooth effectiveness and chewing effectiveness. Chewing behaviour has particular importance to food particle reduction in ruminants, because they spend long periods chewing during both initial ingestion and ruminating. The majority of studies find significant unexplained variance when CE is predicted using tooth features or chewing behaviour parameters. There is also little agreement as to what is the key morphological factor determining tooth effectiveness, or what is the relationship between tooth effectiveness and chewing behaviour. The type, maturity stage and physical presentation of the food also contribute to the final particle size after food has been chewed, because of the involvement of the concentration of chemical components of the cell walls (acid detergent and neutral detergent fibres, lignin) and the architectural structure of the plant tissues in particle breakdown. The relationships between body mass and tooth effectiveness, chewing behaviour and CE are also discussed.     

The Content of Elements in Infant Formulas and Drinks Against Mineral Requirements of Children

The present study aimed at analysing the content of fluorine (F), calcium (Ca), magnesium (Mg), iron (Fe) and zinc (Zn) in the drinks for children and infant formulas, a popular supplement or substitute for breast milk produced from cow milk on an industrial scale. Ca, Mg, Zn and Fe concentrations were determined using atomic absorption spectrophotometer, while F levels using a potentiometric method. F levels in the examined formula samples increased with the intended age range, until the intended age of 1 year, and then decreased. A lower content of Ca, Mg and Zn was observed in formulas intended for children <1 year of age and higher for older children. Fe content increased with the age range. A statistically significant higher content of Ca, Mg, Zn and Fe in samples intended for children with phenylketonuria in comparison to those intended for healthy children or children with food allergies was noted. The content of the analysed elements in juices and nectars showed the highest contents in products intended for infants (under 6 months of age). The lowest levels of elements tested were found in drinks for children over 6 months of age. In conclusion, the concentrations of the examined elements in infant formulas and juices for children were decidedly greater than the standards for the individual age groups. Although the absorption of these elements from artificial products is far lower than from breast milk, there is still the fear of consequences of excessive concentrations of these minerals.     

Exposure to food advertising on television: Associations with children's fast food and soft drink consumption and obesity

There is insufficient research on the direct effects of food advertising on children's diet and diet-related health, particularly in non-experimental settings. We employ a nationally-representative sample from the Early Childhood Longitudinal Survey–Kindergarten Cohort (ECLS-K) and the Nielsen Company data on spot television advertising of cereals, fast food restaurants and soft drinks to children across the top 55 designated-market areas to estimate the relation between exposure to food advertising on television and children's food consumption and body weight. Our results suggest that soft drink and fast food television advertising is associated with increased consumption of soft drinks and fast food among elementary school children (Grade 5). Exposure to 100 incremental TV ads for sugar-sweetened carbonated soft drinks during 2002–2004 was associated with a 9.4% rise in children's consumption of soft drinks in 2004. The same increase in exposure to fast food advertising was associated with a 1.1% rise in children's consumption of fast food. There was no detectable link between advertising exposure and average body weight, but fast food advertising was significantly associated with body mass index for overweight and obese children (≥85th BMI percentile), revealing detectable effects for a vulnerable group of children. Exposure to advertising for calorie-dense nutrient-poor foods may increase overall consumption of unhealthy food categories.     

正交设计优选马蹄莲鲜切花染色技术初步研究

利用正交设计选优方法探讨5种食用色素对马蹄莲鲜切花染色的最佳条件,得出5种食用色素的染色剂浓度、染色时间、染液pH值的最佳组合分别为:柠檬黄9g/L、6h、7.1,胭脂红12g/L、5h、8.5,果绿6g/L、5.5h、6.0,日落黄9g/L、5h、9.2,苋菜红9g/L (或12g/L)、6h、9.4;染色后切花瓶插寿命稍有缩短,但能达到切花所要求的5~8d观赏期。     

Decolorization Screening of Synthetic Dyes by Anaerobic Methanogenic Sludge Using a Batch Decolorization Assay

The nonspecific ability of anaerobic sludge bacteria obtained from cattle dung slurry was investigated for 17 different dyes in a batch assay system using sealed serum vials. Experiments using Reactive Violet 5 (RV 5) showed that sludge bacteria could effectively decolorize solutions having dye concentrations up to 1000 mg l⁻¹ with a decolorization efficiency of above 75% during 48 h of incubation. Headspace gas composition of anaerobic batch systems for varying dye concentration revealed that lower concentrations of RV 5 (upto 500 mg l⁻¹) were found to be stimulatory to the methanogenic activity of sludge bacteria. However at higher dye concentrations, the headspace gas composition was found to be similar to batch assay controls without dye, indicating that dye at higher concentrations was inhibitory to methanogenic bacteria of sludge. The optimum inoculum and incubation temperature for maximum decolorization of RV 5 was found to be 9.0 g l⁻¹(in terms of total solids) and 37°C, respectively. Of sixteen other dyes tested, nine (Reactive Black 5, Reactive Blue 31, Reactive Blue 28, Reactive Red HE8B, Reactive Yellow, Reactive Golden Yellow, Mordant Orange, Novatic Olive R S/D & Navilan Yellow GL) were decolorized with more than 88% efficiency; three (Orange II, Navy Blue HER & Novatic Blue BC S/D) were decolorized with about 50–65% efficiency, whereas other three dyes (Procion Orange H2R, Procion Brilliant Blue HGR & Novatic Blue BC S/D) were decolorized with less than 40% efficiency. Though Ranocid Fast Blue was decolorized with about 92.5% efficiency, this was merely due to sorption, whereas the other dyes were decolorized due to biotransformation.     

Price elasticity of the demand for sugar sweetened beverages and soft drinks in Mexico

A large and growing body of scientific evidence demonstrates that sugar drinks are harmful to health. Intake of sugar-sweetened beverages (SSB) is a risk factor for obesity and type 2 diabetes. Mexico has one of the largest per capita consumption of soft drinks worldwide and high rates of obesity and diabetes. Fiscal approaches such as taxation have been recommended as a public health policy to reduce SSB consumption. We estimated an almost ideal demand system with linear approximation for beverages and high-energy food by simultaneous equations and derived the own and cross price elasticities for soft drinks and for all SSB (soft drinks, fruit juices, fruit drinks, flavored water and energy drinks). Models were stratified by income quintile and marginality index at the municipality level. Price elasticity for soft drinks was −1.06 and −1.16 for SSB, i.e., a 10% price increase was associated with a decrease in quantity consumed of soft drinks by 10.6% and 11.6% for SSB. A price increase in soft drinks is associated with larger quantity consumed of water, milk, snacks and sugar and a decrease in the consumption of other SSB, candies and traditional snacks. The same was found for SSB except that an increase in price of SSB was associated with a decrease in snacks. Higher elasticities were found among households living in rural areas (for soft drinks), in more marginalized areas and with lower income. Implementation of a tax to soft drinks or to SSB could decrease consumption particularly among the poor. Substitutions and complementarities with other food and beverages should be evaluated to assess the potential impact on total calories consumed.     

黄色鲤、蓝色鲤、红色鲤杂交的体色及鳞被遗传特性

进行黄色鲤(Cyprinus carpio)、蓝色鲤及红色鲤的自交和杂交试验,统计分析子代的体色及鳞被分离情况。结果表明,实验选择的亲本,红色鲤的体色和鳞被都是纯合基因型;蓝色鲤的体色是纯合型,鳞被是杂合型;黄色鲤的体色和鳞被都是杂合型。它们彼此杂交的体色遗传规律较复杂,子代中不但具有亲本的红、黄、蓝体色,还出现了其他色彩,如青灰色、白色、青黄色和蓝白色,部分红色个体的背部还呈暗黑色。同时,实验还观察了不同体色鲤的鳞片、鳍条色素细胞分布情况,分析和讨论了鲤杂交的体色遗传特性。     

Decolorization of synthetic dyes and production of manganese-dependent peroxidase by new fungal isolates

Two yeasts, Debaryomyces polymorphus, Candida tropicalis, and two filamentous fungi, Umbelopsis isabellina, Penicillium geastrivorus, could completely decolorize 100 mg Reactive Black 5 (RB 5) l^–1 within 16–48 h. Manganese-dependent peroxidase (MnP) activities between 60 and 424 U l^–1 were detected in culture supernatants of three of these organisms indicating the color removal by enzymatic biodegradation but with P. geastrivorus there was no ligninolytic enzyme activity in its culture and the decolorization was mainly due to biosorption to mycelium. Extensive decolorization by D. polymorphus (69–94%) and C. tropicalis (30–97%) was obtained with five other azo dyes and one anthraquinone dye. Except for Reactive Brilliant Blue KNR and Reactive Yellow M-3R, the four azo dyes, Reactive Red M-3BE, Procion Scharlach H-E3G, Procion Marine H-EXL and Reactive Brilliant Red K-2BP, induced D. polymorphus to produce MnP (105–587 U l^–1). However, MnP activities of 198–329 U l^–1 were only detected in the culture of C. tropicalis containing Reactive Red M-3BE and Reactive Brilliant Red K-2BP, respectively.     

RNA-recognizing function of the DNA-recognizing structure helix-turn-helix in ribosomal proteins S4 and S7 of Escherichia coli and plant chloroplasts

The segments which satisfy the necessary requirements for DNA-recognizing structure helix-turn-helix coding have been found in amino acid sequences of RNA-recognizing E. coli ribosomal proteins S4 and S7. It has appeared that among these segments there are those that in chloroplasts S4 and S7 homologues satisfy these necessary requirements also: S4-97-121 and 108-132 (Ec), 91-115 and 102-126 (Zea mays); S7-109-133 (Ec) 110-134 (Euglena gracilis, Glycine max). Such segments have been confronted with known experimental data on 16S rRNA-binding region localization. It has appeared: 1) the segment 97-121 of S4 is localized in RNA-recognizing fragment 46-124 and one of two RNA-binding regions of this fragment containing Lys-120--belongs to the predicted DNA-recognizing structure; the segment 109-133 of S7 includes the only RNA-binding region of S7-113-117. It is concluded that E. coli ribosomal proteins S4 and S7 and their homologues from plant chloroplasts have a DNA-recognizing structure helix-turn-helix performing the RNA-recognizing function.