Predicting feed quality - chemical analysis and in vitro evaluation

As the ideal method of assessing the nutritive value of a feedstuff, namely offering it to the appropriate class of animal and recording the production response obtained, is neither practical nor cost effective a range of feed evaluation techniques have been developed. Each of these balances some degree of compromise with the practical situation against data generation. However, due to the impact of animal-feed interactions over and above that of feed composition, the target animal remains the ultimate arbitrator of nutritional value. In this review current in vitro feed evaluation techniques are examined according to the degree of animal-feed interaction. Chemical analysis provides absolute values and therefore differs from the majority of in vitro methods that simply rank feeds. However, with no host animal involvement, estimates of nutritional value are inferred by statistical association. In addition given the costs involved, the practical value of many analyses conducted should be reviewed. The in sacco technique has made a substantial contribution to both understanding rumen microbial degradative processes and the rapid evaluation of feeds, especially in developing countries. However, the numerous shortfalls of the technique, common to many in vitro methods, the desire to eliminate the use of surgically modified animals for routine feed evaluation, paralleled with improvements in in vitro techniques, will see this technique increasingly replaced. The majority of in vitro systems use substrate disappearance to assess degradation, however, this provides no information regarding the quantity of derived end-products available to the host animal. As measurement of volatile fatty acids or microbial biomass production greatly increases analytical costs, fermentation gas release, a simple and non-destructive measurement, has been used as an alternative. However, as gas release alone is of little use, gas-based systems, where both degradation and fermentation gas release are measured simultaneously, are attracting considerable interest. Alternative microbial inocula are being considered, as is the potential of using multi-enzyme systems to examine degradation dynamics. It is concluded that while chemical analysis will continue to form an indispensable part of feed evaluation, enhanced use will be made of increasingly complex in vitro systems. It is vital, however, the function and limitations of each methodology are fully understood and that the temptation to over-interpret the data is avoided so as to draw the appropriate conclusions. With careful selection and correct application in vitro systems offer powerful research tools with which to evaluate feedstuffs. (C) 2003 Elsevier B.V. All rights reserved.

Chemical and Bioactive Quality Traits During Fruit Ripening in Eggplant (S-melon gena L.) and Allied Species

A chemical and bioactive quality evaluation of phytochemicals content of 10 eggplant lines and three allied species (S. sodomaeum, S. aethiopicum and S. integrifolium) was performed. The eggplant lines were divided into the two subgroups of delphinidin-3-rutinoside (D3R) and nasunin (NAS) typologies, on the basis of the anthocyanin detected in their fruit skin. The allied species had higher glycoalkaloids content, lower soluble solids and PPO activity and absence of anthocyanins compared to the eggplant lines; S. sodomaeum stood out for high phenols content. Orthogonal contrast revealed a higher sugar content and low PPO activity in NAS- compared to D3R-typologies, whereas higher chlorogenic acid and anthocyanin contents were present in D3R-typologies. The main effect of the ripening was a decrease in phenols and in the PPO activity, not evidenced in S. sodomaeum, and an increase of glycoalkaloids in overripe fruits.A good relationship was found between superoxide anion scavenging capacity and chlorogenic acid. This study highlighted the pattern of accumulation, also evidencing variations, of several phytochemicals during the eggplant fruit development and ripening.

Using chemical and physical parameters to define the quality of Pardo River water (Botucatu-SP-Brazil)

This paper aims to study the ecological system of the Pardo River, at the source and lower-order passages, which are in the Botucatu area, São Paulo State, Brazil. This study was carried out to determine water quality with some chemical-physical indicators, coliforms, and chemical species of samples taken monthly, 1995/02-1996/01, from eight sampling stations sited along the Pardo River. The results in the river monitoring are discussed based on annual averages, analysis of variance, and compared to Tukey's Studentized Range-HSD, and principal component analysis (PCA) was applied to normalize data to assess association between variables. We can conclude that the variables used are very efficient for identifying and that the dry season shows the worst water quality. These were caused by organic matter, nutrients (originate) from anthropogenic sources (spatial sources) and mainly municipal wastewater, affecting the quality and hydrochemistry of the river water, which have been differentiated and assigned to polluting sources. Meanwhile, the degree of degradation of the Pardo River is low (sewage treatment carried out by the city of Pardinho is efficient), leaving the water of the river suitable for use by the population of Botucatu, after conventional treatment (Conama, Resolucao No. 20, CONAMA, Brazilia DF, 09-23, 1986-the water of the Pardo river is classified as level 03). (C) 2001 Elsevier B.V. Ltd. All rights reserved.

Anthracnose control and mango quality (Mangifera indica L.) cv. van dyke after hydrothermal and chemical treatment

Anthracnose causes severe damage to the mango skin. Therefore, there is need to do the post-harvest phytosanitary treatment of the fruits through soaking in fungicide solution, which associated with the hydrothermal treatment has resulted into improved benefits. The present work has aimed at studying anthracnose control and post-harvest quality of mangoes (Mangifera indica L.), cv. Van Dyke after hydrothermal treatment associated with chemical through the physical, physicochemical, chemical and phytopathologic analyses. The mangoes coming from the commercial orchard of the town of Jana ba-MG, of the 2000 crop, were harvested at the commercial maturation stage. After selection according to color uniformity, size and absence of mechanic and physiologic injuries, they were shipped in plastic boxes to the EPAMIG - CTNM - Nova Porteirinha - MG, fruit post-harvest laboratory, where the samples were submitted to the hydrothermal treatment in cold bath in solution containing the fungicides Thiabendazole (Tecto 400 mL/100L), Proclaraz (Sportak 10L/100L) and Imazalil (Magnate 200mL/100L). After air-drying, the fruits were packed in plastic trays and stored at room temperature (25 +/- 2 degrees C and RH 70%) for a 12-day period and evaluated as to the intrinsic quality characteristics every 4 days. The experiment was conducted a completely randomized with 8 treatments, 4 replicates and experimental unit consisting of 4 fruits. The variations of pH, total soluble solids, total titrable acidity and total soluble sugars have not endangered the organoleptic characteristics of mangoes cv. Van Dyke stored under room temperature (25 +/- 2 degrees C and RH 70%) till 8 days' storage. The association of the hydrothermal treatment with the chemical was efficient in fruit anthracnose control for till 12 days' storage. The fungicide Prochloraz (Sportak 110 mL/100L), associated with the hydrothermal treatment, completely inhibited the appearance of anthracnose symptoms.

Evaluation of electrical conductivity, pH and refractive index as physico-chemical parameters for quality control of Aveloz homeopathic solutions

Euphorbia tirucalli Lineu (Aveloz) belongs to the family Euphorbiaceae and is used in the treatment of cancer and warts. Some studies have reported that phorbol esters are the active principles responsible for the antitumor activity of Aveloz. The production of these molecules occurs in greater quantity in May, during the morning. This study aimed to evaluate whether the physico-chemical parameters of Aveloz homeopathic aqueous solutions such as pH, electrical conductivity and refractive index change due to storage time. Such parameters were measured regularly for 180 days. All solutions were prepared according to the method of grinding with lactose and subsequent dissolution in aqueous medium, as described in the Brazilian Homeopathic Pharmacopoeia, using as starting point the Aveloz latex collected in May. Homeopathic aqueous solutions containing only lactose were also prepared and evaluated as a control group. The potencies that were analyzed for electrical conductivity, pH and refractive index were: 4cH, 7cH, 9cH, 12cH, 14cH, 15cH, 29cH, 30cH. As a result, we found out that there was only statistical difference (p=0.035) in electrical conductivity between the homeopathic solutions containing Aveloz and the homeopathic solutions without Aveloz, when 15cH potency was compared. We also observed that the electrical conductivity increased with the aging of the solutions but is not directly related to the pH or the refractive index of the solutions, indicating that the aging process may alter the electrical conductivity of the homeopathic medicines. The presence of gas inside the glass that stores these solutions may affect the electrical conductivity measurements. Finally, no statistically significant difference was observed (p> 0.05) in the pH and refractive index.

Use of anatomical, chemical, and molecular genetic characteristics in the quality control of medicinal species: a case study of sarsaparilla (Smilax spp.)

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Influence of sanitization on the physico-chemical and microbiological quality of organic and conventional broccoli

The present study was carried out in order to evaluate the effect of chlorinated and ozonized water on the physico-chemical characteristics of broccoli, produced under organic and conventional cultivation procedures. Organic and conventional broccolis were subjected to two sanitation treatments, using chlorine and ozone, and were kept under cold storage for seven days. Analyses of pH, titrable acidity, soluble solids and weight loss were performed and the content of Cu, Mn and Zn was determined. In addition, the presence of pesticides was verified. The results show no influence of the cultivation method or the sanitation treatment on sample weight loss. Cultivation methods and sanitizing treatments affected broccoli pH, titratable acidity, and soluble solids during the evaluation period. No differences regarding the metal content on organic and conventional broccoli were observed. Furthermore, the presence of organochlorine compounds, nor other pesticides, was not detected both in organic and conventional vegetables.

Chemical, biochemical and microbiological indicators to assess soil quality in temperate agro-ecosystems

Soil is a critically important component of the earth’s biosphere. Developing agricultural production systems able to conserve soil quality is essential to guarantee the current and future capacity of soil to provide goods and services. This study investigates the potential of microbial and biochemical parameters to be used as early and sensitive soil quality indicators. Their ability to differentiate plots under contrasting fertilization regimes is evaluated based also on their sensitivity to seasonal fluctuations of environmental conditions and on their relationship with soil chemical parameters. Further, the study addresses some of the critical methodological aspects of microplate-based fluorimetric enzyme assays, in order to optimize assay conditions and evaluate their suitability to be used as a toll to asses soil quality. The study was based on a long-term field experiment established in 1966 in the Po valley (Italy). The soil was cropped with maize (Z. mays L.) and winter wheat (T. aestivum L.) and received no organic fertilization, crop residue or manure, in combination with increasing levels of mineral N fertilizer. The soil microbiota responded to manure amendment increasing it biomass and activity and changing its community composition. Crop residue effect was much more limited. Mineral N fertilization stimulated crop residue mineralization, shifted microbial community composition and influenced N and P cycling enzyme activities. Seasonal fluctuations of environmental factors affected the soil microbiota. However microbial and biochemical parameters seasonality did not hamper the identification of fertilization-induced effects. Soil microbial community abundance, function and composition appeared to be strongly related to soil organic matter content and composition, confirming the close link existing between these soil quality indicators. Microplate-based fluorimetric enzyme assays showed potential to be used as fast and throughput toll to asses soil quality, but required proper optimization of the assay conditions for a precise estimation of enzymes maximum potential activity.