Efficacy of supplementing Aspergillus awamori in enhancing growth performance, gut microbiota, digestibility, immunity, and antioxidant activity of heat-stressed broiler chickens fed diets containing olive pulp.

BACKGROUND: Gut microbes play a significant role in digestion, developing immunity, and intestinal health. Therefore, direct-fed microbials are used to modify gut microbiota, maintain a healthy digestive system, enhance immunity, and promote the broilers' performance. In addition, it has a role in improving the utilization of unconventional feed ingredients (olive pulp, OP). This study provides the potential role of Aspergillus awamori in enhancing gut microbial content, nutrient utilization, growth performance, and antioxidative status in heat-stressed broiler chickens fed diets containing olive pulp. METHODS: Three hundred chicks (Ross 308; one day old) were divided into four treatment groups (75 chick/ group) randomly, as follows; CON: chicks fed a basal diet based on corn and soybean meal, OP10: chicks fed a diet containing 10% OP, OA1: chicks fed a diet containing OP with A. awamori at 100 mg per kg, OA2: chicks fed a diet containing OP with A. awamori at 200 mg per kg. RESULTS: Adding A. awamori to the broiler diet that contains OP had a positive effect on productive performance via enhancing nutrition digestibility, body weight gain, feed conversion ratio, and carcass characteristics. A. awamori supplementation had a positive impact on immune responses by increasing serum immunoglobulin G and the relative weight of bursa of Fabricius (P < 0.05) compared to the other groups. Chickens fed A. awamori showed a noticeable improvement in the oxidative status through the increase in the level of serum superoxide dismutase, and glutathione peroxidase, and the decrease in the level of malondialdehyde. Feeding A. awamori also modified the intestinal microbial content by increasing the population of Lactobacillus (P < 0.05). CONCLUSIONS: Our study indicated that adding 200 mg A. awamori reduced the negative effect of heat stress by modifying the microbial content of the intestine, immune response, and enhancing feed utilization, thus improving broiler performance, as well as, improving the nutritional value of the olive pulp. Therefore, adding A. awamori to the OP diet can be effectively used in heat-stressed broiler diets.

Impacts of enzymes and probiotic in improving the utilization of sieved olive pulp meal in growing rabbit diets.

Objective: This research assesses the utilization of sieved olive pulp (SOP) in the diet of growing rabbits through the use of an exogenous enzyme or dry yeast as a pretreatment. Materials and Methods: One hundred sixty-eight male V-Line rabbits aged 5 weeks (weighing 550 ± 25 gm) were randomly divided into seven groups with eight replicates each as follows: the control group was fed a basal diet without supplementation; while the other six groups were fed basal diets containing 20% and 25% of SOP and supplemented with 0.1 gm/kg Econase (E), 0.5 gm/kg dry yeast (Y), and a combination of both. The experiment lasted for 8 weeks. Results: The results indicated that supplementation of E, Y, and EY into rabbit diets containing SOP improved live body weight, body weight gain, feed conversion ratio, and nutrient digestibility. A higher dressing percentage was observed in the groups fed a 20% and 25% SOP diet supplemented with EY (p < 0.05). The treated groups showed an increase in total protein, albumin, globulin, A/G ratio, total antioxidant capacity, superoxide dismutase, and glutathione peroxidase (p < 0.05), while there was a significant decrease in triglycerides, total cholesterol, and malondialdehyde levels (p < 0.05) compared to the control. Rabbit groups fed an SOP diet supplemented with E, Y, or EY demonstrated higher (p < 0.05) economic efficiency compared to the control. Conclusion: Supplementing the diet of rabbits containing SOP with exogenous enzymes and/or dry yeast enhances the nutritional value of SOP while improving rabbit performance, nutrient digestibility, and antioxidant status.

Suitability of dried olive pulp in slow-growing broilers: performance, meat quality, oxidation products, and intestinal mucosa features.

To assess the effect of dietary dried olive pulp (DOP) on growth performance, meat traits and oxidation, and intestinal mucosa features, a total of 180 male slow-growing broiler chickens (Hubbard) were divided into 3 groups and fed 3 isonitrogenous and isoenergetic diets from 14 d of age until slaughter (49 d). The treatments varied according to 3 DOP levels: a control diet without DOP (DOP0, 0%) and 2 test diets containing 5 and 10% of DOP (DOP5 and DOP10, respectively). Duodenal morphometric indices were measured at the end of the feeding period and included: villus height, crypt depth, villus-to-crypt ratio, and villus surface area. Dietary DOP had no adverse effect on growth performance, dressing percentage, or breast yield of broilers. The breast muscle pH at 24 h was significantly higher in birds fed DOP10 diet compared to those on DOP0 and DOP5 diets. Meat color was also affected by dietary treatments. Feeding DOP did not influence breast meat fatty acid composition, whereas meat from DOP-fed broilers resulted less susceptible to lipid and protein oxidation compared to control diet. Including DOP up to 10% in diet resulted in higher duodenal villus height, crypt depth, and villus height to crypt depth ratio as well as villus surface area. Based on our findings, dietary DOP supported productive traits of slow-growing broilers preserving meat from oxidation and improving intestinal morphometric features. As a result, the current study assessed that olive by-product can be used in broiler ration, resulting in a valuable ingredient as replacement for conventional feeds, which could reduce feeding costs due to the low cost of the olive by-product. Thus, using olive by-products as poultry feed may become economically feasible for producers where the olive oil industries play an important economic role.

Calcite in combination with olive pulp biochar reduces Ni mobility in soil and its distribution in chili plant.

The presence of Ni above the permissible limit in agriculture soils poses negative effects on soil health, crop quality, and crop productivity. Surprisingly, the usage of various organic and inorganic amendments can reduce Ni mobility in the soil and its distribution in the crops. A pot experiment was conducted to elucidate the effects of olive pulp biochar (BR), calcite (CAL), and wheat straw (WS), as sole amendments and their mixtures of 50:50 ratio, added to Ni polluted soil on Ni mobility in the soil, Ni immobilization index (Ni - IMi), soil enzymatic activities, Ni distribution in parts of chili plant, Ni translocation factor and bioaccumulation factor in fruit, plant growth parameters and oxidative stress encountered by the plants. Outcomes of this pot experiment revealed that amendments raised soil pH, improved soil enzymatic activities, values of Ni - IMi, while significantly reduced bioavailable Ni fraction in the post-harvest soil. However, the highest activities of acid phosphatase, urease, catalase, and dehydrogenase by 50, 70, 239, and 111%, respectively, improvement in Ni - IMi up to 60% while 60% reduction in the bioavailable Ni fraction was observed in BR + CAL treatment, compared to control was noted. Among all amendments, the top most reduction in Ni concentrations in shoots, roots, fruit, Translocation Factor (TF), and Bioaccumulation Factor (BAF) values of fruit by 72%, 36%, 86%, 72%, and 86%, in BR + CAL treatment, compared to control. Moreover, the plants growing on BR + CAL amended Ni contaminated soil showed the topmost improvement in plant phonological parameters while encountered the least oxidative stress. Such findings refer to the prospective usage of BR + CAL at 50:50 ratio than BR, CAL, WS alone, and BR + WS as well as WS + CAL for reducing Ni mobility in the soil, improving Ni - IMi, soil enzymatic activities, plant phonological and oxidative stress while reducing Ni distribution in plant parts. Novelty statementIn this experiment, it was hypothesized that amending Ni polluted soil with olive pulp biochar (BR), CAL, and WS as alone soil amendments and their combinations at 50:50 ratios can reduce Ni bioavailability in soil, Ni distribution in chili plant and oxidative stress encountered by the plants. Moreover, these amendments may improve, soil enzymatic activities, Ni immobilization index, plant phenological traits. Therefore, it was aimed to undertake useful scientific planning and research, to restore and rehabilitate the dwellings, biological resources and to minimize the sufferings of the peoples in nutrient-poor Ni contaminated soils, by improving soil health and chili productivity.

Use of Mediterranean By-Products to Produce Entire Male Large White Pig: Meat and Fat Quality.

A total of 70 male growing non-castrated pigs (Large White), with a 23.07 ± 2.87 kg average body weight (BW), were randomly allocated to three treatments in a 103 day trial: a CONTROL diet and two experimental diets, ALLIUM (5 g/kg of Allium spp. extract) and OLIVE (100 g/kg of olive pulp). Animals were slaughtered at 115 kg live body weight. Meat and fat quality were analyzed. Animals fed ALLIUM and OLIVE had higher water holding capacity (WHC) than those fed the control diet. No significant differences were observed between groups for cooking loss, drip losses and color CIELab. No antioxidant effect was observed on an oxygen radical absorbance capacity (ORAC) test. Animals fed OLIVE presented a more unsaturated fatty acid profile than CONTROL and ALLIUM. Meat from ALLIUM group and OLIVE showed her values of brightness and meat odor than CONTROL. Mean scores of sensory analyses (color, odor, flavor and juiciness) of cooked samples were similar for the three treatments, with the meat samples from the ALLIUM and OLIVE treatments being less hard. Consumers did not reflect a preference for any of the treatments. Both by-products could be used for pork production.

The SARS-CoV-2-Inactivating Activity of Hydroxytyrosol-Rich Aqueous Olive Pulp Extract (HIDROX®) and Its Use as a Virucidal Cream for Topical Application.

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has spread globally. Although measures to control SARS-CoV-2, namely, vaccination, medication, and chemical disinfectants are being investigated, there is an increase in the demand for auxiliary antiviral approaches using natural compounds. Here we have focused on hydroxytyrosol (HT)-rich aqueous olive pulp extract (HIDROX®) and evaluated its SARS-CoV-2-inactivating activity in vitro. We showed that the HIDROX solution exhibits time- and concentration-dependent SARS-CoV-2-inactivating activities, and that HIDROX has more potent virucidal activity than pure HT. The evaluation of the mechanism of action suggested that both HIDROX and HT induced structural changes in SARS-CoV-2, which changed the molecular weight of the spike proteins. Even though the spike protein is highly glycosylated, this change was induced regardless of the glycosylation status. In addition, HIDROX or HT treatment disrupted the viral genome. Moreover, the HIDROX-containing cream applied on film showed time- and concentration-dependent SARS-CoV-2-inactivating activities. Thus, the HIDROX-containing cream can be applied topically as an antiviral hand cream. Our findings suggest that HIDROX contributes to improving SARS-CoV-2 control measures.

Effects of Dried Olive Pulp Dietary Supplementation on Quality Characteristics and Antioxidant Capacity of Pig Meat.

Olive pulp belongs to agro-industrial by-products, and its addition into livestock diets generally result in neutral or positive effects on performance. However, the data concerning the effects of olive by-products on pork meat characteristics are scarce. The aim of this preliminary study was therefore to examine the effects of dried olive pulp (DOP) dietary supplementation on quality parameters and oxidative stability of pig meat. Twenty finishing pigs were allocated to two groups: C that was provided with a control diet, and DOP that was fed with an isonitrogenous and isoenergetic diet supplemented with dried olive pulp at the level of 50 g/kg or 5%. As indicated, cold carcass weight, pH, lightness, redness, cooking loss, and tenderness were not influenced by DOP inclusion. Only meat yellowness (a*) was significantly decreased in DOP meat samples. Moreover, meat oxidation values tended to decrease in the DOP group after one day, but no further differences were observed after four, six, and eight days of refrigerated storage. It can be concluded that DOP dietary supplementation could be recommended as a feasible approach, especially in the Mediterranean region to reduce diet formulation costs, while no significant side effects on pork meat quality are observed.

YEAST dynamics during the natural fermentation process of table olives (Negrinha de Freixo cv.).

Yeast population and dynamics associated to spontaneous fermentation of green table olives Negrinha de Freixo cv. were evaluated. Olives and brine samples were taken at different fermentation times, and yeast were enumerated by standard plate count and identified by sequencing of the internal transcribed spacer (ITS) region of the nuclear ribosomal DNA (rDNA). Saccharomyces cerevisiae was the most frequent, followed by Candida tropicalis, Pichia membranifaciens and Candida boidini, representing together 94.8% of the total isolates. Galactomyces reessii was also identified for the first time in table olives. The highest species diversity was found between 44 and 54 days of fermentation, both in brine and olive pulp. Furthermore, high similarity was observed between brine and olive pulp microbiotas. In conclusion, these results give valuable information to table olive industrials in order to achieve more knowledge on the fermentation process of this important Protected Designation of Origin product.

Efficient extraction of olive pulp and stone proteins by using an enzyme-assisted method.

An efficient protein extraction protocol for proteins from olive pulp and stone by using enzymes was developed. For this purpose, different parameters that affect the extraction process, such as enzyme type and content, pH, and extraction temperature and time, were tested. The influence of these factors on protein recovery was examined using the standard Bradford assay, while the extracted proteins were characterized by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). The best extraction conditions were achieved at pH 7.0 and 5% (v/v) Palatase® 20000 L (lipase) for pulp and Lecitase® Ultra (phospholipase) for stone proteins. The optimal extraction temperature and time were 30 and 40 °C for 15 min for pulp and stone tissues, respectively. Under these conditions, several protein extracts coming from olive fruits of different genetic variety were analyzed, their profiles being compared by SDS-PAGE. The developed enzyme-assisted extraction method showed faster extraction, higher recovery, and reduced solvent usage than the nonenzymatic methods previously described in the literature. In the case of stone proteins, different electrophoretic profiles and band intensities were obtained that could be helpful to distinguish samples according to their genetic variety.

Proteomic platform for the identification of proteins in olive (Olea europaea) pulp.

The nutritional and cancer-protective properties of the oil extracted mechanically from the ripe fruits of Olea europaea trees are attracting constantly more attention worldwide. The preparation of high-quality protein samples from plant tissues for proteomic analysis poses many challenging problems. In this study we employed a proteomic platform based on two different extraction methods, SDS and CHAPS based protocols, followed by two precipitation protocols, TCA/acetone and MeOH precipitation, in order to increase the final number of identified proteins. The use of advanced MS techniques in combination with the Swissprot and NCBI Viridiplantae databases and TAIR10 Arabidopsis database allowed us to identify 1265 proteins, of which 22 belong to O. europaea. The application of this proteomic platform for protein extraction and identification will be useful also for other proteomic studies on recalcitrant plant/fruit tissues.