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91.
Betalains have been widely used as natural colorants for many centuries, but their attractiveness for use as colorants of foods (or drugs and cosmetics) has increased recently due to their reportedly high anti-oxidative, free radical scavenging activities and concerns about the use of various synthetic alternatives. The main commercial sources of betalains are powders and concentrates of red beet (Beta vulgaris) or cactus pear (Opuntia ficus-indica) extracts. However, in recent years the technical and commercial feasibility of various in vitro systems to produce them biotechnologically has been explored. These research activities have included assessments of novel approaches for cultivating plant cell or tissue cultures, and diverse bioreactor systems for increasing production levels of secondary metabolites. This paper reviews recent progress in plant in vitro systems for producing betalain pigments. In addition, the factors that could be manipulated, the bioreactor systems that could be used, and the strategies that could be applied to improve betalain production are discussed.  相似文献   
92.
This study investigated the longevity, fecundity, and host feeding of a wild and a commercially reared strain of Trichogramma minutum Riley (Hymenoptera: Trichogrammatidae) when presented with peach extrafloral nectar. Both the wild and commercial T. minutum strains lived longer and parasitized more Grapholita molesta (Busck) eggs when provided peach extrafloral nectar and water than when provided only water. Nectar-fed wild and commercially reared females lived 11.6 and 9.9 d and produced 105.2 and 61.0 offspring, respectively. When provided only water, wild females lived 3.3 d and produced 52.8 offspring, whereas commercially reared females lived 2.0 d and produced 24.4 offspring. Nectar feeding significantly increased the number of G. molesta eggs destroyed by host feeding by both wild and commercial strains.  相似文献   
93.
CGC-MS of alkaloids in Leucojum aestivum plants and their in vitro cultures   总被引:1,自引:0,他引:1  
Underivatised alkaloid mixtures extracted from intact plants and in vitro cultures of Leucojum aestivum (Amaryllidaceae) were investigated by capillary GC-MS. Excellent peak resolution for the alkaloids was exhibited and isomers of galanthamine and N-formylnorgalanthamine were well separated. Fourteen alkaloids of galanthamine, lycorine and crinane types were identified, 11 in the intact plants and eight in the in vitro cultures.  相似文献   
94.
We implemented a 2-yr program to reduce organophosphorus and carbamate insecticide use and mitigate their associated risks as they relate to peach production in New Jersey and elsewhere. The main thrust integrated mating disruption with ground cover management practices to reduce oriental fruit moth, Grapholita molesta (Busck) (Lepidoptera: Tortricidae), and tarnished plant bug, Lygus lineolaris (Palisot de Beauvois) (Heteroptera: Miridae), abundance and damage. This Reduced Risk Peach Arthropod Management Program was compared with adjacent conventionally managed peach orchards. In 1999, we found 2.3 times fewer L. lineolaris and stink bugs (Euschistus servus (Say), E. tristigmus (Say), Acrostemum hilare (Say) (Heteroptera: Pentatomidae) and 2.0 times less heteropteran damaged peaches in reduced-risk orchards when compared with conventionally managed orchards. In 2000, we observed 4.9 times fewer heteropteran insects in reduced-risk orchards but damage levels were not significantly different between the two programs. In both years, G. molesta mating disruption gave at least 4 mo of noninsecticidal control of this major pest. The reduced-risk program provided a level of pest control that was equal to or better than conventional peach pest management programs while using fewer organophosporus and carbamate insecticides.  相似文献   
95.
96.
The small group of resurrection plants is a unique model which could help us in further understanding of abiotic stress tolerance. The most frequently used approach for investigations on gene functions in plant systems is genetic transformation. In this respect, the establishment of in vitro systems for regeneration and micro propagation is necessary. On the other hand, in vitro cultures of such rare plants could preserve their natural populations. Here, we present our procedure for in vitro regeneration and propagation of Haberlea rhodopensis – a resurrection plant species, endemic for the Balkan region.  相似文献   
97.
Atanasov AT 《Bio Systems》2005,82(2):137-142
A linear relationship exists between total metabolic energy per life span PT(ls) (kJ) and body mass M (kg) of 54 poikilothermic species (Protozoa, Nematoda, Mollusca, Asteroidae, Insecta, Arachnoidae, Crustacea, Pisces, Amphibia, Reptilia and Snakes): PT(ls) = A(ls*)M(1.0838), where P (kJ/day) is the rate of metabolism and T(ls) (days) is the life span of animals. The linear coefficient A(ls*) = 3.7 x 10(5) kJ/kg is the total metabolic energy, exhausted during the life span per 1 kg body mass of animals. This linear coefficient can be regarded as relatively constant metabolic parameter for poikilothermic organisms, ranging from 0.1 x 10(5) to 5.5 x 10(5) kJ/kg, in spite of 17-degree differences between metabolic rate and body mass of animals. A linear relationship between total metabolic energy per life span and body mass of only 48 poikilothermic multicellular animals (without Protozoa) is: PT(ls) = A(ls*)M(0.9692) with linear coefficient A(ls*) = 2.34 x 10(5) kJ/kg. Since a power relationship exists between the rate of metabolism and body mass of animals of the type: P = aMk (a and k are the alometric constants), an empiric rule could be formulated, that life span is a time interval for which the total metabolic energy per life span becomes proportional to body mass of animals and power coefficient k becomes approximately 1.0.  相似文献   
98.
Betalains biosynthesis and antiradical scavenging activity were investigated during cultivation of four hairy root cultures of Beta vulgaris, obtained from different cultivars (Bordo, Egyptian, Detroit 2 and Detroit Dark Red). The best producer of betalains was a hairy root culture from Beta vulgaris cv. Detroit Dark Red (13.27 mg/g dry weight total pigment production). The ethanol extract, derived from roots of the same culture grown for 15 days under submerged conditions, showed a high antiradical activity (83% of inhibition of the stable DPPH.).  相似文献   
99.
Fourteen aromatic and 24 aliphatic acids were determined by GC-MS analysis of acidic fractions obtained from Paeonia peregrina and Paeonia tenuifolia roots. Benzoic acid and its monohydroxy-, dihydroxy- and trihydroxy-derivatives are the main acid components of both Paeonia species. Some fractions could serve as a source of benzoic, 4-hydroxybenzoic, vanillic and gallic acids, as well as of ethyl gallate. The fractions inhibited the growth of Staphylococcus aureus, Escherichia coli and Candida albicans.  相似文献   
100.
In recent years, there has been a great deal of attention toward the molecular machinery relevant to age-related progression controlled through the external intervention of polyphenols- an epigenetic-modulating diet. Natural products modulate cellular longevity through histone post-translational modification and can also induce the upregulation of autophagy, thus reducing the level of acetyl coenzyme A (AcCoA). In addition, the effect of caloric restriction (CR) on cancer-related chronic inflammation is of great significance in aging. In line with this, SIRT1 protein levels are expanded in response to calorie restriction mimetics (CRM), in this way acting as autophagy inducers relevant to cancer prevention.  相似文献   
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