Efficient Harvesting Methods

Bioflocculants are also being explored, including the introduction of bacteria [206] and filamentous fungi [207, 208] to induce algal aggregation. Some algal 

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Machine picking is the preferred method of harvesting, but the vineyard and the variety must be suited to the requirements of the machines so that the machines will harvest efficiently. Machine-harvesting costs are less than hand picking, but machine harvesting is less efficient in some varieties. There are some varieties that cannot be picked by machine. There is no consistent difference in wine quality between the two harvesting methods, at least as far as sherry-type wines are concerned. 

The fact that menthol is produced from both renewable and fossil feedstocks allows for an interesting study in sustainability. In order to produce the same crop year after year, it is necessary to use fertilisers to replenish the nitrogen and minerals which the plant takes from the soil. Secondary metabolites such as menthol and essential oils occur at a level of, at most, only a few per cent of the dry weight of the herb. Therefore, in order to produce an economic return, it is necessary to use efficient, mechanical methods of cultivation and harvesting. A full life cycle analysis of menthol production reveals that production from cultivation of mint plants consumes more fossil fuel, produces more carbon dioxide effluent and has more environmental impact than either of the leading synthetic routes. 

Metabolic profiling can be done on freshly harvested, freeze-dried or frozen stored material. This decision depends on the type of tissue to be analysed (whole plants, roots, leaves, fruits, seeds) and on the analytical techniques used. An efficient extraction method should be reproducible and lead to the extraction of a wide range of constituents across the different chemical classes, taking care to suppress enzyme activity that would change the metabolite composition. A common solvent is the methanol/ water mixture, which has been used in different proportions (80/20, 70/30, 50/50 or 20/80) in the case of polar extraction. For instance, De Vos et al. (2007) described a protocol for LC/ MS of plant materials and proposed that 75%... 

On the rayon washing system, a minimum water-to-fiber ratio for the batt weights used was about 55/1. The Mississippi cotton was much more difficult to wet out than either the California or Texas cottons. The Mississippi cotton, compared with the California and Texas cotton, was a low noncellulose cotton and had a more hydrophobic surface. Thus, the wettability and, consequently, the washing efficiency of cotton is related to and dependent upon the surface characteristics of the cotton. Configuration of the materials on the fiber surface are related to variety, area of growth, environmental conditions, method and time of harvest, storage conditions, and other factors. 

Various enzymes are produced intracellularly. Hence, following cell harvesting, an efficient disruption process to disintegrate the cell to release the intracellular proteins is needed. Some types of cells are broken readily by gentle treatment, while others are very resistant to breakage. A number of cell disruption methods have been developed ... 

This brief calculation is not meant to judge the viability of solar energy, but simply to provide discussion about what the appropriate methods should be to harvest the energy, which is incident on the earth. If one uses the larger estimate for exergy flux, which makes up the solar surface incident component (86,000 TW), or can obtain larger efficiencies in solar cells and use more of the earth s land for solar cells, the picture becomes much more optimistic. 

Activity Determination (Day 6) The cells are harvested for the evaluation of enzyme activities. This can be performed in situ via the incubation of the cells with the enzyme substrates (Table 2). Activity can also be determined from the cell homogenates or microsomal fractions of the cells. The in situ method is the most efficient, and would allow one to use 24-well or 96-well plates. The microsomal method would require the use of larger cell culture plates (e.g. 100-mmdiameterplates). DME substrates used in the hepatocyte enzyme induction assay are shown in Table 4. 

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