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1.
Zusammenfassung Fünf Speisekartoffelsorten wurden w?hrend einer sechsmonatigen Lagerung fünfmal auf α-Solanin und α-Chaconin untersucht. Es
wurden vier Gewebebereiche der Knolle getrennt überprüft. Der Gesamtglykoalkaloidgehalt betrug im Augenbereich 164, in der
restlichen Schale 101 und in der Gef?ssbündelzone mit ?usserem Speichergewebe 8mg/100g. Trockensubstanz. Im restlichen Innenk?rper
waren nur noch Spuren (0.164mg/100g TS) nachzuweisen. Zwischen den Sorten und diesen Gewebepartien traten statistisch gesicherte
Wechselwirkungen auf, die im wesentlichen von einer Sorte verursacht wurden. W?hrend der Lagerung sind die Alkaloidgehalte
leicht, aber statistisch nicht gesichert gesunken.
α-Solanin und α-Chaconin kamen generell im Verh?ltnis von etwa 1∶1.5vor; die Korrelation zwischen beiden Formen ist sehr eng
(r=0.865). Bezogen auf die gesamte Knolle lagen die Gesamtglykoalkaloide je nach Sorte zwischen 2.4 und 8mg/100g Frischsubstanz
und damit im gesundheitlich unbedenklichen Bereich.
Summary Five table potato cultivars (Erna, Granola, Gusto, Ulse, Margit) from the same source were examined for their content of α-solanine and α-chaconine during a sixmonths storage period. For the testing and subsequent analysis the tubers were dissected into four kinds of tissues: eye-zone, peel, vascular bundle region, medulla. The total glycoalkaloid content (TGA) in the total tuber mass varied between 2.4 and 8mg per 100g fresh matter depending on cultivar (Fig. 1). Despite significant differences between cultivars (Table 1), all potato cultivars remained within the safe range during the entire storage period. Remarkable differences in TGA per 100g dry matter could be noted in the tuber parts. For the eye-zones a TGA of 164mg was found; the peel region showed 101mg and the vascular bundle zone 8mg. The medulla of the tubers contained only traces of TGA (0.164mg/100g dry matter, Fig. 2). The statistical analysis only revealed significant interactions between cultivars and tuber parts (Table 1), mainly caused by the cultivar Gusto which showed higher contents of α-solanine and α-chaconine in its vascular bundle regions (Figs 3–5). The ratio between amounts of α-solanine and α-chaconine was approximately 1∶1.5, and after eliminating effects of cultivar, storage and tuber parts, the correlation coefficient between amounts was 0.865. This close correlation can be used for breeding. The non-significant, slightly negative effect of the six-months storage period on alkaloid content was noteworthy. It is assumed that only after long storage periods or through inappropriate storage (sprouting of tubers) a significantly higher glycoalkaloid content may be expected.
相似文献
2.
Summary A new, efficient and economic method employing Medium Pressure Liquid Chromatography (MPLC) for the isolation of the two majorSolanum tuberosum L. glycoalkaloids (α-solanine and α-chaconine) is described. Potato peelings are homogenised with 5% acetic acid, the glycoalkaloids
purified by filtration through an XAD-2 column and then by precipitation from the aqueous solution. The resulting glycoalkaloid
fraction was purified by MPLC using a Silica Gel column and a CHCl3:MeOH:2% NH4OH mixture (70∶30∶5) as mobile phase to yield pure α-chaconine and a-solanine. This methodology can be used to obtain glycoalkaloids
for enthomology and toxicological research where large amounts of these compounds are required. 相似文献
3.
Summary Methods for the estimation of amylolytic activity are reviewed. A procedure for the routine extraction of amylolytic activity
from freeze-dried powder prepared from potato tubers is described. The extraction medium is buffered at pH 7.0 and contains
glycerol, dithiothreitol, calcium chloride and the non-ionic detergent, nonidet P-40. α-Amylase activity and exoamylolytic
activity were estimated in crude extracts of potato tubers using the substrates, blockedp-nitrophenyl-maltoheptaoside andp-nitrophenyl-maltopentaoside respectively. These substrates are included in kits supplied by Biocon, (UK) Ltd to measure the
α- and ?-amylase activity in cereals. The validity of using these kits for the determination of α- and ?-amylase activity
in potato tuber tissue is discussed. 相似文献
4.
Summary Plants of early potato cultivars were sampled at successive harvests during tuber development and individual tubers were analysed
for α-solanine and α-chaconine using high-performance liquid chromatography. Mean tuber total glycoalkaloid concentration
(α-solanine plus α-chaconine) per plant decreased with time and statistically significant differences between cultivars were
observed in the patterns of decline during tuber growth. The mean tuber ratio of α-chaconine to α-solanine increased during
tuber development and was also affected by genotype. Total glycoalkaloid concentration for individual tubers of marketable
sizes (up to 50 g fresh weight) exceeded the safety limit of 20 mg per 100 g fresh weight for cultivars Home Guard and British
Queen but not for Rocket. These differences were attributable to differences in both rates and patterns of glycoalkaloid accumulation
during tuber development, although in all cultivars results were consistent with glycoalkaloid accumulation occurring in the
expanding peripheral cell layers of tubers for a considerable period after tuber initiation. 相似文献
5.
Summary Fractions containing Δ5- and Δ7-sterols, 4-methyl-sterols, triterpenic alcohols, tocopherols and hydrocarbons were isolated by TLC from petroleum ether extracts
of the haulm and tuber sprouts of cv Désirée. Sterol and triterpenic alcohol fractions of unsaponifiable lipids of the haulm
and tuber sprouts were found to contain twelve sterols and four triterpenic alcohols, respectively. 24R-4-stigmasten-3-on,
Δ7, Δ7, lanosterol, cycloeucalenol and obtisufoliol have not been identified previously in unsaponifiable lipids from haulm and
sprouts. In the hydrocarbon fractions of the haulm extract, C23-to C33-n-parafins, C19-and C31-cyclohexyl hydrocarbons, C22-to C38-olefins and squalene were identified, and in the hydrocarbon fractions of the tuber sprouts C12-to C26-olefins and squalene were identified. 相似文献
6.
M. Z. Stanković Nada C. Nikolić R. Palić M. D. Cakić V. B. Veljković 《Potato Research》1994,37(3):271-278
Summary The kinetics of enzymatic transformation of total glycoalkaloids (TGA) in haulm and tuber sprouts of potato to solanidine
and the kinetics of solanidine isolation from plant material were studied. The optimum reaction conditions for the enzymatic
TGA transformation were found for haulm to be: plant material to liquid phase 1:4 w/v, temperature 35°C, pH 5.4; and for tuber
sprouts: plant material to liquid phase 1:3 w/v, temperature 37°C, pH 5.4. The. maximum degree of enzymatic transformation
of TGA in haulm and tuber sprouts of 65 and 75%, respectively, was achieved after 50h. Carbon tetrachloride was the best solvent
for solanidine extraction from the plant materials. The optimum ratio of plant material to carbon tetrachloride for the isolation
of solanidine was 1:8 w/v for both extraction cycles, ensuring a yield of solanidine of approximately 55 and 65% from haulm
and tuber sprouts, respectively, after 30 min. 相似文献
7.
Summary Amylase activity in extracts of sprouted tubers was optimised at final concentrations of soluble starch in the incubation
medium of 0.6–2.0 mg cm−3. Optimum pH was 6. The exclusion of calcium ions from extraction and incubation media did not result in reduced enzyme activity.
This, together with a shift in the absorption maximum of the starch-iodine complex almost identical to that observed with
pure β-amylase, indicates the predominance of β-amylase in the extracts. Over a 15-min incubation period the linearity of
the response was dependent upon the volume of tuber extract included in the assay medium. Gel filtration of extracts did not
influence this response. 相似文献
8.
Wild Solanum species are characterized by several types of glycoalkaloids (GAs), which are usually not found in commercial potato cultivars.
These alkaloids serve as defence compounds against herbivores and microorganisms, especially fungi. In this study, the GA
composition of tuber and leaf material of 17 wild Solanum species was analysed qualitatively by liquid chromatography-electrospray ionization-mass spectrometry (LC-ESI-MS) and quantitatively
by high-performance liquid chromatography. The GAs identified were α-solanine, α-chaconine, β-chaconine, solasonine, solamargine,
demissine, dehydrodemissine, α-tomatine, dehydrotomatine, commersonine, dehydrocommersonine, leptine I and leptine II. Most
species accumulated the common potato GAs α-solanine and α-chaconine in tubers and solasonine and solamargine additionally
in leaves. In some species, such as S. acaule ssp. acaule, S. demissum and S. polyadenium, substantial amounts of unusual alkaloids were detected. By using LC-ESI-MS, we detected several minor alkaloids such as
dehydrogenated forms of α-tomatine, demissine and commersonine for the first time. Total GA content, expressed as the sum
of the four main alkaloids α-solanine, α-chaconine, solamargine and solasonine differed from species to species. In general,
GA contents in leaf tissue were higher and GA patterns were more complex than those of tubers. 相似文献
9.
Summary Tubers of the potato cultivars Record, Wilja, Pentland Dell and Brodick (formerly clone 137371) were sampled before and after
storage at either 4°C or 10°C. Reducing sugar content stayed constant during storage at 10°C in all four cultivars but rose
greatly during the first 6–12 weeks of storage at 4°C in Record, Wilja and Pentland Dell but not in Brodick. Amylolytic activity
was determined after 5 weeks storage using blockedp-nitrophenyl maltoheptaoside as substrate for α-amylase,p-nitrophenyl maltopentaoside as substrate for β-amylase, andp-nitrophenylglucopyranoside as substrate for α-glucosidase. The values obtained from tubers stored at 4°C were higher than
those from tubers stored at 10°C, the differences being much less in Brodick than in the other three cultivars. 相似文献
10.
A simple and rapid method for the determination of naturally occurring, potentially hazardous glycoalkaloids (GAs) in potatoes
and their products has been developed. The procedure is based on the on-line solid-phase extraction of the acetic acid extracts
from potato products and combined with liquid chromatography (LC)-mass spectrometry (MS) in a fully automated system (Symbiosis™,
Spark Holland Instruments, Emmen, The Netherlands). As sorbent material HySphere™ 18HD was used for alkaloid enrichment. GAs
were eluted with the LC gradient and directly analysed by MS. Detection of the analytes was achieved in the sensitive multiple
reaction monitoring mode using two characteristic ions (m/z 98 as a qualifier for GAs and m/z 868.3 as a quantifier for α-solanine or m/z 852.4 for α-chaconine). Typical validation data for method precision (v
k α-solanine = 5.3–6.5, v
k α-chaconine = 3.4–15.4), accuracy (average recovery of α-solanine = 84%, average recovery of α-chaconine = 87%) and linearity
over the range from 1 to 1,000 ng ml−1 (R
2 = 0.9915 for α-solanine, R
2 = 0.9939 for α-chaconine) with detection limits of 0.3 ng ml−1 for α-chaconine and 0.5 ng ml−1 for α-solanine were obtained. GA contents of commercial potato products were determined by the new on-line method and afterwards
compared with those obtained with an established high-performance LC routine procedure. Better performance of the on-line
procedure was obvious from the standard deviations of both methods. Other advantages included a strong reduction of overall
analysis time, human intervention and solvent consumption as well as waste production. The time required for the on-line analysis
was 5 min, which would allow processing of almost 100 samples in 8 h. 相似文献
11.
Summary The method of Vadukul (1991) for determining maleic hydrazide (MH) was modified and gave recoveries of free MH of 89%±4%.
The values recorded on individual tubers ranged from 2–14 mg kg−1. Maleic hydrazide was evenly distributed throughout the tuber (peel, outer and inner flesh) but concentration increased slightly
as tuber size increased. The concentration of free MH decreased from 7 to 3 mg kg−1 over the storage period of 5 1/2 months. Acid hydrolysis released substantial amounts of MH particularly from older potatoes
(13 mg kg−1) compared with 6 mg kg−1 from new potatoes, implying that free MH is gradually converted to a bound form with time after treatment. No evidence was
found for the presence of a β-glucoside of MH. 相似文献
12.
Adisakwattana S Lerdsuwankij O Poputtachai U Minipun A Suparpprom C 《Plant foods for human nutrition (Dordrecht, Netherlands)》2011,66(2):143-148
Inhibition of α-glucosidase and pancreatic α-amylase is one of the therapeutic approaches for delaying carbohydrate digestion,
resulting in reduced postprandial glucose. The aim of this study was to evaluate the phytochemical analysis and the inhibitory
effect of various cinnamon bark species against intestinal α-glucosidase and pancreatic α-amylase. The results showed that
the content of total phenolic, flavonoid, and condensed tannin ranged from 0.17 to 0.21 g gallic acid equivalent/g extract,
from 48.85 to 65.52 mg quercetin equivalent/g extract, and from 0.12 to 0.15 g catechin equivalent/g extract, respectively.
The HPLC fingerprints of each cinnamon species were established. Among cinnamon species, Thai cinnamon extract was the most
potent inhibitor against the intestinal maltase with the IC50 values of 0.58 ± 0.01 mg/ml. The findings also showed that Ceylon cinnamon was the most effective intestinal sucrase and
pancreatic α-amylase inhibitor with the IC50 values of 0.42 ± 0.02 and 1.23 ± 0.02 mg/ml, respectively. In addition, cinnamon extracts produced additive inhibition against
intestinal α-glucosidase and pancreatic α-amylase when combined with acarbose. These results suggest that cinnamon bark extracts
may be potentially useful for the control of postprandial glucose in diabetic patients through inhibition of intestinal α-glucosidase
and pancreatic α-amylase. 相似文献
13.
Lee BB Cha MR Kim SY Park E Park HR Lee SC 《Plant foods for human nutrition (Dordrecht, Netherlands)》2007,62(2):79-84
Organic solvent (methanol, ethanol, and acetone) extracts and water extracts of cherry (Prunus serrulata var. spontanea) blossoms were prepared, and antioxidant activities of the extracts were evaluated. Methanolic CBE (100 μg/ml) showed the
highest total phenol content (104.30 μM), radical scavenging activity (34.2%), and reducing power (0.391). The effect of CBE
on DNA damage induced by H2O2 in human leukocytes was evaluated by Comet assay. All CBE was a potent dose dependent inhibitor of DNA damage induced by
200 μM of H2O2, methanolic CBE showed the most strong inhibition activity. The methanolic CBE of 500 μg/ml showed 38.8% inhibition against
growth of human colon cancer cell line HT-29. These results indicated that cherry blossoms could provide valuable bioactive
materials. 相似文献
14.
Iwai K 《Plant foods for human nutrition (Dordrecht, Netherlands)》2008,63(4):163-169
The dietary intake and control of blood glucose levels are very important in hyperglycemic patients and α-glucosidase inhibitors
are a cost-effective means to preventing the progression of diabetes. In search of a natural inhibitor from food materials,
α-glucosidase inhibitory activity and the anti-hyperglycemic effects of a brown alga, Ecklonia stolonifera, were investigated using non-insulin dependent diabetic mice. Methanolic extract of E. stolonifera (MEE), which contains a high content of polyphenols, showed strong inhibition of α-glucosidase in vitro. Male KK-Ay mice, a genetically non-insulin dependent diabetic model, showed hyperglycemia with aging, but the ingestion of MEE suppressed
the increase in plasma glucose and lipid peroxidation levels in unfasted KK-Ay mice dose dependently. In KK-Ay mice, which were fed the MEE diet for 4 weeks, MEE moderated the elevation of plasma glucose levels after the oral administration
of maltose. The polyphenols in MEE were estimated to be phlorotannins by HPLC-PDA and LC/MS analyses. These results demonstrate
that E. stolonifera, seaweed typically used as a health food, has strong antidiabetic and antioxidant effects in vivo, thus, it may have beneficial properties in the prevention of diabetes and could be useful in the development of an antidiabetic
pharmaceutical and functional food. 相似文献
15.
Monsuang Yangthong Nongporn Hutadilok-Towatana Wutiporn Phromkunthong 《Plant foods for human nutrition (Dordrecht, Netherlands)》2009,64(3):218-223
The aqueous extracts of four marine algae, Caulerpa racemosa var. macrophysa, Gracilaria tenuistipitata var. tenuistipitata, Sargassum sp., and Ulva lactuca, from the coastal areas in Southern Thailand, were prepared by boiling dried seaweed powder in water for 3 h, and by autoclaving
each sample at 120 °C for 3 h. They were then freeze-dried and evaluated for their antioxidant activities using DPPH (1, 1-diphenyl-2-picrylhydrazyl),
hydroxyl radical (OH•) and superoxide anion (O2•−) scavenging assays. Boiling extracts of the seaweeds, except C. racemosa, were found to have higher total phenolic contents (TPC) than those obtained from the autoclave method. The antioxidant results
also showed that O2•− scavenging activity existed only in the boiling extracts of C. racemosa, G. tenuistipitata, and U. lactuca. In DPPH and OH• assays, however, almost all the boiling extracts were less active than the autoclave ones. Among the four alga species, Sargassum sp. was the most active. Both extracts of this seaweed had the highest TPC and also displayed the strongest DPPH• and OH• inhibitory activities. A strong positive-correlation between the antioxidant potency and TPC of the autoclave extracts was
found, while for the boiling extracts such relation was very weak. This result thus reflected that in addition to the phenolic
compounds, there might be some other active components present in these extracts involved in the antioxidant activity. 相似文献
16.
Antioxidant activity and phenolic content of chestnut (Castanea sativa) shell and eucalyptus (Eucalyptus globulus) bark extracts 总被引:1,自引:0,他引:1
G. Vzquez E. Fontenla J. Santos M.S. Freire J. Gonzlez-lvarez G. Antorrena 《Industrial Crops and Products》2008,28(3):279-285
Chestnut (Castanea sativa) shell and eucalyptus (Eucalyptus globulus) bark, waste products of the food and wood industries, respectively, were analysed as potential sources of antioxidant compounds. The extraction yield, the antioxidant activity and total phenols content of the extracts were greater in chestnut shell than in eucalyptus bark for most of the extraction conditions essayed. Extraction of chestnut shell with a 2.5% Na2SO3 aqueous solution led to the highest extraction yield, 25.6%, total phenols, 13.4 g gallic acid equivalent/100 g oven-dried shell, and FRAP antioxidant activity, 80.7 mmol ascorbic acid equivalent/100 g oven-dried shell. Extraction with methanol:water (50:50, v/v) provided the best results for eucalyptus bark. The antioxidant activity and the total phenols content of the extracts had a positive linear correlation. FTIR spectroscopy confirmed the higher content of phenolic compounds in chestnut shell extracts compared to eucalyptus bark extracts. Chestnut shell extracts were characterized by the presence of high molecular weight species whereas lower molecular weight species were predominant in eucalyptus bark extracts. 相似文献
17.
Lílian da Silva Fialho Valéria Monteze Guimarães Everaldo Gonçalves de Barros Maurilio Alves Moreira Luiz Antônio dos Santos Dias Maria Goreti de Almeida Oliveira Inês Chamel José Sebastião Tavares de Rezende 《Plant foods for human nutrition (Dordrecht, Netherlands)》2006,61(2):83-85
Common beans have a high nutritional value, but contain galactooligosaccharides (GO), which cause flatulence and intestinal discomfort in humans. The biochemical composition of ten bean cultivars was determined to select those of high protein and low GO contents. The cultivars varied in carbohydrate (47.02–60.17%), GO (3.12 – 5.71%), protein (22.17–33.50%), lipid (1.13–1.81%), moisture (11.42–12.93%) and ash contents (4.08–5.61%). ‘Mexico 222’ presented the highest α-galactosidase activity. Protein and GO contents were positively correlated. ‘Perry Marrow’ combined high protein and low GO concentrations, indicating it can be used in improvement programs aiming at high-quality cultivars for human consumption. 相似文献
18.
To identify the potential of green leafy vegetables (GLV) as antioxidants, methanolic extracts of Amaranthus sp., Centella asiatica, Murraya koenigii and Trigonella foenum graecum were studied for their antioxidant activity in different systems at multiple concentrations. Total antioxidant activity assessed
by phosphomolybdenum method, free radical scavenging activity by 1,1-diphenly-2-picryl hydrazyl (DPPH), reducing power and
ferrous ion chelating activity were determined. The GLV were analyzed for ascorbic acid, total and β-carotene and total polyphenol
contents. The ascorbic acid, total carotene, β-carotene and total phenolic content (tannic acid equivalents) of the GLV ranged
between 15.18–101.36, 34.78–64.51, 4.23–8.84 and 150.0–387.50 mg/100 g GLV, respectively. The extracts were found to have
significantly different levels of antioxidant activities in the systems tested. The total antioxidant activity was highest
in Murraya koenigii (2,691.78 μmol of ascorbic acid/g sample) and least in Centella asiatica (623.78 μmol of ascorbic acid/g sample). The extract concentration causing 50% inhibition of DPPH (IC50) was determined (M. koenigii < C.asiatica < Amaranthus sp. < T. graecum). The maximum DPPH scavenging activity and reducing power was exhibited by Murraya koenigii. Multiple regression analysis showed that the relationship of total antioxidant activity, free radical scavenging activity,
and reducing power with polyphenol and total and β-carotene was highly significant.
Paper awarded the Young Scientist Award in Experimental Nutrition at the Young Scientist Award Session of the 39th Annual
Meet of the Nutrition Society of India, Hyderabad, India on 15–16th Dec 2007. 相似文献
19.
J. Weber 《Potato Research》1988,31(1):3-10
Zusammenfassung Nach Inokulation mit abgestuften Bakteriendichten wurde über eine Vitalf?rbung von Knollengewebe der Schwellenwert zur F?uleausl?sung
bestimmt. Seine Erh?hung nach 24 h Wundheilung charakterisiert die Effizienz der biochemischen F?uleabwehr. Die Abwehrreaktionen
des Knollengewebes und der Prozess der F?uleausl?sung sind in unterschiedlichem Masse von der Temperatur, der Feuchtigkeit
und dem O2- sowie dem CO2-Gehalt der Atmosph?re abh?ngig.
Summary The inoculum densities (effective dose) ofErwinia carotovora sub sp.atroseptica (Eca) needed to initiate infection of tuber tissue before and after a 24 h wound-healing period, was determined using a vital stain. The effects of various treatments on the efficiency of the defence reaction associated with wound healing, and on rot initiation were manifested as changes in the effective dose. The defence reaction was inhibited by temperatures <10°C, reduced O2 levels ≤5%, and CO2 proportions ≥20% (Fig. 3a and 4a). Moisture loss in stored tubers increased their defence reaction compared to that of freshly harvested ones (Table 1). The effect of these factors on Eca development was identical to that which occurs in potato production where tuber wounds are generally contaminated with Eca. Rot initiation was best prevented by removal of water (Table 1), storage at 15°C, avoidance of reduced O2 levels <10% and CO2 accumulation (Fig. 3b and 4b).相似文献
20.
K. N. Suseelan C. R. Bhatia R. Mitra 《Plant foods for human nutrition (Dordrecht, Netherlands)》1997,50(3):211-222
Two major lectins, MBL-I and MBL-II, were purified fromVigna radiata L. seeds using ion-exchange and gel filtration chromatography techniques. MBL-I was found to be a tetramer with native M.W.
of 132 kDa and subunit M.W. of 33 kDa having α-galactosidase activity. MBL-II consisted of two monomeric lectins with M.W.
of 94 kDa and 89 kDa which were associated mainly with β-galactosidase activity. Both MBL-I and MBL-II are D-galactose-specific
lectins. 相似文献