Blueberry phenolic compounds and more broadly, phytochemicals, exert regulatory effects including a decrease in proinflammatory gene expression/production in part through the modulation of the NF-κB pathway. A modulation of the MAPK pathway by blueberry phytochemicals is less evident with contradictory observations reported but may also play a role. Blueberry phytochemicals decreased DNA damage in cells in vitro, via the reduction of ROS production, lipid peroxidation, and an increase in antioxidant enzyme activities. Despite many in vitro studies on blueberry extracts, no specific compounds have emerged as singly responsiblefor the regulatory effects on inflammation and oxidative stress. Virtually all studies have focused on blueberry phenolic extracts or fractions, with a large emphasis on anthocyanins. Health effects of dietary anthocyanins have been extensively reported and discussed , and berries provide an excellent vector for anthocyanin consumption. Blueberries have a complex anthocyanin profile and both major anthocyanidin derivatives, malvidin and delphinidin, have demonstrated a reduction of inflammatory markers in different in vitro models of intestinal inflammation and endothelial dysfunction . Although it is highly likely that anthocyanins largely contribute to the health benefits provided by blueberries, as supported by the number of studies focusing on those compounds, it is doubtful that they are entirely responsible for the bio-activities. Several in vitro studies compared different fractions of blueberry phytochemicals,black plastic pots for plants with reports of similar or better effects by other phenolic fractions and/or whole blueberry extract compared with anthocyanins .
These different studies highlight that mechanisms of action of individual blueberry compounds and fractions are context and/or model specific. More studies comparing the effect on individual compounds and well-defined combinations of molecules in different systems are needed to investigate the impact of a system’s environment or system-specific regulation on the bio-activity of blueberries. Although the amplitude of the effect of individual compounds appears to be widely specific to the model studied, the use of whole fractions of the fruits seems to alleviate inflammation and/or oxidative stress more consistently across models, despite not always demonstrating the strongest effects compared with specific blueberry fractions. As the health effects of polyphenols have been extensively described, more data on other phytochemicals should be gathered as they may also exert health benefits. Other notable phytochemicals in blueberries include ascorbic acid , polysaccharides , and volatile compounds and could contribute to inflammatory or oxidative responses of cells to stimuli. A blueberry volatile extract, high in monoterpenes , modulated the inflammatory response in LPS-induced RAW 264.7 cells through inhibition of the NF-κB pathway . Phenolic compounds, although carrying anti-inflammatory and antioxidant modulatory effects, may not be solely responsible for the health benefits of blueberries. Whether the phytochemicals act in synergy or target different molecular pathways remains to be elucidated.Although the scope of this review is limited to blueberries, the anti-inflammatory and antioxidant effects and mechanisms are likely applicable to other commonly consumed berries. Berries are generally rich in polyphenols, particularly anthocyanins, flavonols, and proanthocyanidins, but the profile of each berry species, and even within varieties, harbors differences in terms of the individual compounds present and their respective concentration .
Gasparrini et al. reviewed in detail the anti-inflammatory effects of several berries in cellular models using LPSinduced inflammation, and consistently report alleviation of inflammation by berry phytochemicals through inhibition of NF-κB and MAPK pathways. Other reviews also discuss and compare the anti-inflammatory properties of berries, in preclinical and human models . Moore et al. and Gu et al. have reported similar anti-inflammatory effects of berry volatiles compared with phenolic extracts for cranberries, blackberries, blueberries, red and black raspberries, and strawberries. Notably, the bio-activities of berry polyphenol extracts do not always explain the overall anti-inflammatory effects observed with whole berries , highlighting that potential health effects of berries as a group derived from highly diverse phytomolecules. After consumption, blueberries and their phytochemicals undergo metabolism through phase II enzymatic reactions in the enterocytes and hepatocytes or microbial metabolism in the gut . Metabolites are more likely to reach target sites inside the body and exert health benefits than their parent compounds . Evidence of the role of blueberry metabolites in the modulation of inflammation and/or oxidative stress has also been established . Metabolites of elderberry were tested in RAW 264.7 and dendritic cells, and p-coumaric, homovanillic, 4- hydroxybenzoic, ferulic, protocatechuic, caffeic, and vanillic acids [also reported to be blueberry metabolites ], exerted a dose-response inhibitory effect on NO . Studies regarding berry catabolites are less abundant than studies on berry parent phytochemicals but have gained interest in more recent literature. These studies of microbeand host-modified phytochemicals are extremely important to fully understand the potential anti-inflammatory effects of blueberry consumption. Although most of the evidence focuses on the effect of individual compounds, it is essential to consider the potency of these metabolites in profiles similar to what occurs physiologically.
To take the compound profile and physiologically available doses into account, Rutledge et al. treated LPS-induced rat microglial cells with serum from subjects having regularly consumed blueberry, strawberry, or a placebo powder blends over 90 d. The blueberry consumption decreased NO production, TNF-α secretion, iNOS expression, and moderately modulated COX-2 protein expression in the cells . This type of design allows the integration of a more realistic profile of parent compounds and metabolites from blueberry consumption, at physiological doses, within a cell-culturebased model. The current review summarizes the extensive amount of literature available on blueberry phytochemicals and inflammation using cell-based models. This choice comes with limitations, since it can be challenging to interpret results using specific concentrations of berry-derived molecules on cells when concentrations of these metabolites at the site of the target organs may not be established. There have been major differences in concentrations used to treat the cells, ranging anywhere from tens of μg/mL to mg/mL for total polyphenols and from tens of ng/mL to ≤1.2 mg/mL for anthocyanin fractions. Some of these concentrations are much higher than the blood concentrations that would be present in the body after consumption, as bioavailability of anthocyanins in the body is estimated to be lower than 2%, and peaking at 100 nmol/L after consumption of grape/blueberry juice . The relevance of the findings of cell-culture-based studies in complex human systems needs further investigation. These studies should comprise of well-controlled clinical trials, with the relevant choice of placebo controls and inclusion criteria depending on the specific blueberry phytochemical and physiological condition investigated. Future studies should also quantify the entire suite of berry-derived molecules and derivatives in key pools such as the blood, concurrently with physiologic indices of inflammation and oxidative stress.Fruit, nut, and berry crops are commonly grouped into one of three categories: temperate, subtropical, and tropical. Temperate zone crops include almond, apple, apricot, peach, grape, blueberry, and strawberry . Avocado, citrus, and guava are considered to be subtropical, while banana, cashew, and pineapple are tropical . Generally, temperate and subtropical crops can be grown in San Mateo and San Francisco Counties ,drainage pot but tropical crops are rarely successful. This publication focuses on temperate and subtropical crops. Temperate zone crops generally require a period of cold temperature during the winter months for successful flower and fruit development. This cold temperature period is measured in “chill hours” . Some crops require many chill hours, while others require few. This is called the crop’s “chill requirement.” When selecting temperate zone crops, it is important to choose only those crops that have a chill requirement that will be met at your location. Subtropical crops, such as citrus, loquat, and guava, require little or no chilling. Native to warm-climate regions, these crops can be injured by cold temperatures during winter and spring months, and they require heat during the growing season for fruit maturation and flavor.There are a growing number of examples of a positive relationship between diversity and ecosystem services. As an ecosystem service, pollination can increase the fruit or seed quality or quantity of 39 of the world’s 57 major crops, and a more diverse pollinator community has been found to improve pollination service. For some crops, wild bees are more effective pollinators on a per visit basis than honey bees and/or can functionally complement the dominant visitor. A less explored reason is that in diverse communities, interspecific interactions potentially alter behaviour in ways that increase pollination effectiveness. Little is known about how community composition affects pollinator behaviour and the role such species interactions play in determining diversity–ecosystem service relationships. Interspecific interactions can result in non-additive impacts of diversity on ecosystem functions.
Examples include the facilitation of resource capture in diverse groups of aquatic arthropods, and non-additive increases in pest suppression and alfalfa production in enclosures with diverse natural enemy guilds. In diverse communities, one mechanism by which species interactions may augment function is the potential to modify the behaviour and the resulting effectiveness of the ecosystem service providers. Interactions with non-Apis bees cause Apis mellifera L. to move more often between rows of sunflower, increasing their pollination efficiency. Such changes in pollinator movement are particularly important in crop species with separate male and female flowers, and those with self-incompatibility . As well as direct interaction and disturbance, avoidance of interspecific chemical cues and resource competition have the potential to alter pollinator foraging movements. Global human population growth is putting greater pressure on agricultural production. There is concern over how to meet the increasing demand for food, while at the same time safeguarding ecosystems and biodiversity. In the future, land currently under agricultural production will have to be more intensively managed to increase yields and/or more land will have to be converted to agriculture. Given the negative impact agriculture has already had on biodiversity, it is important that future steps to increase production be made environmentally sustainable. In the last 50 years, the fraction of agricultural production requiring biotic pollination has more than tripled. When compared with crops that are not pollinator-dependent, those that are moderately pollinator-dependent have shown slower growth in yield and faster expansion in area from 1961 to 2006. Almond is a mass-flowering, varietally self-incompatible crop species, highly dependent on biotic pollination. Almond orchards are generally planted with alternating rows of two or more varieties. Planting a single variety per row facilitates harvest, but complicates pollination because pollen must be transferred between rows to achieve fruit set. To allow for management activities, trees between rows are further apart than those within the same row . Apis mellifera tend to forage within a tree and then move down the same row, probably because less effort is required to move to the next tree in the same row or because the rows act as visual markers that influence movement. This foraging pattern means A. mellifera tend to move more incompatible pollen, limiting their pollination effectiveness. In almond, we investigated whether the presence of nonApis bees affected the behaviour and pollination service of the dominant pollinator species, A. mellifera. Often almond orchards are isolated from natural habitat and non-Apis bees can be completely absent. Therefore, we were able to compare A. mellifera behaviour and pollination effectiveness in diverse bee communities with orchards lacking non-Apis bees. Here, we refer to pollinator effectiveness as the probability an ovule is fertilized following a single visit. We complemented our intensive field sampling with observations in a controlled cage environment, where A. mellifera were introduced along with the blue orchard bee Osmia lignaria Say. We hypothesized that where non-Apis bees were present, such as in sunflower , interspecific interactions would cause A. mellifera to more frequently move between rows. We further hypothesized that an increase in between-row movements by A. mellifera would increase their pollination effectiveness and increase fruit set .In 2011, A. mellifera movements were observed in five orchards isolated from natural habitat, where non-Apis bees were not present. The number of movements by A. mellifera was counted between two trees of different varieties across the orchard row for 1 min. This was repeated a minimum of four times, counting movements between the same two rows, between different adjacent trees. The number of movements by A. mellifera was also counted between two adjacent trees of the same variety within the same orchard row. These two counts were repeated a minimum of eight times down a row along adjacent trees .