Antifungal activity of chili pepper extract with potential for the control of some major pathogens in grapevine

BACKGROUND

In recent years, biofungicides have drawn increasing interest in vineyards for a more sustainable integrated and copper-limited pest management. Among alternatives, botanicals could represent valuable tools, being rich sources of biologically active compounds. Conversely to the well-known antioxidant and biological properties in relation to health benefits, investigation on bioactivity of hot pungent Capsicum sp. products against fungal phytopathogens in vineyards is still scarce. Therefore, the present study aimed at exploring the biologically active compounds profile of a chili pepper (Capsicum chinense Jacq.) pod extract and its antimicrobial properties against some of the major fungal and Oomycetes pathogens of grapevine, including Botrytis cinerea Pers., Guignardia bidwellii (Ellis) Viala & Ravaz and Plasmopara viticola (Berk. & M.A. Curtis) Berl. & De Toni.

RESULTS

The ethyl acetate-extracted oleoresin from the most pungent varieties was rich in capsaicinoids and polyphenols (371.09 and 268.5 μg mg-1 dry weight, respectively). Capsaicin and dihydrocapsaicin, hydroxycinnamic and hydroxybenzoic acids and quercetin derivatives were the most abundant, while carotenoids represented only a minor fraction. The oleoresin was efficient to inhibit all three pathogenic fungi and ED50 values were determined, evidencing that G. bidwellii was the more sensitive (0.233 ± 0.034 mg mL-1 ).

CONCLUSION

The results suggested a potentiality of chili pepper extract for the control of some important grapevine pathogens, their possible application being helpful for the recommended limitation in extensive use of copper in vineyard. The complex mixture of high amounts of capsaicinoids, associated to specific phenolic acids and other minor bioactive components might contribute to the observed antimicrobial action of chili pepper extract. © 2023 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Gas Chromatography Combustion Isotope Ratio Mass Spectrometry to Detect Differences in Four Compartments of Simmental Cows Fed on C3 and C4 Diets

Fatty acids (FAs) metabolism in animals represents an important field of study since they influence the quality and the properties of the meat. The aim of this study is to assess the possibility to discriminate the diets of cows in different animal compartments and to study the fate of dietary FAs in the bovine organism, using carbon isotopic ratios. Five FAs, both essential (linoleic and linolenic) and non-essential (palmitic, stearic, and oleic) in four compartments (feed, rumen, liver, meat) of animals fed two different diets (based on either C3 or C4 plants) were considered. For all compartments, the carbon isotopic ratio (δ13C) of all FAs (with few exceptions) resulted significantly lower in cows fed on C3 than C4 plants, figuring as a powerful tool to discriminate between different diets. Moreover, chemical reactions taking place in each animal compartment result in fraction processes affecting the δ13C values. The δ13CFAs tendentially increase from feed to meat in group C3. On the other hand, the δ13CFAs generally increase from rumen to liver in group C4, while δ13CFAs of rumen and meat are mostly not statistically different. Different trends in the δ13CFAs of the two groups suggested different FAs fates depending on the diet.

Fatty acids stable carbon isotope fractionation in the bovine organism. A compound-specific isotope analysis through gas chromatography combustion isotope ratio mass spectrometry

The contribution of dietary fatty acids to the quality of the meat and their path through the bovine organism is currently the subject of a lot of research. Stable isotope ratio analysis represents a powerful tool for this aim, one that has not been studied in depth yet. In this work, for the first time, the carbon isotopic ratios of six fatty acids (myristic 14:0, palmitic 16:0, stearic 18:0, oleic 18:1n-9, linoleic 18:2n-6 and linolenic 18:3n-3 acids) in different matrixes (diet, rumen, duodenal content, liver and loin) were analysed through gas chromatography combustion isotope ratio mass spectrometry. Moreover, the quantification of the single fatty acids was carried out, providing important information supporting the carbon isotopic ratio results. The variation in the concentration of the fatty acids in the different matrices depends on the chemical modifications they undergo in the sequential steps of the metabolic path. GC-C-IRMS turned out to be a powerful tool to investigate the fate of dietary fatty acids, providing information about the processes they undergo inside the bovine organism.

Influence of dietary inclusion of tannin extracts from mimosa, chestnut and tara on volatile compounds and flavour in lamb meat

Tannins are compounds able to form complexes with proteins limiting their ruminal degradation and thus the synthesis of some odour-active compounds may be inhibited. Tannins are broadly divided in condensed tannins (CT) and hydrolysable tannins (HT). The study aimed to assess the influence of dietary inclusion of three commercial tannin extracts, namely mimosa (Acacia mearnsii; CT), chestnut (Castanea sativa; HT) or tara (Caesalpinia spinosa; HT) on volatile profile and flavour of meat and kidney fat from lambs. Comisana male lambs were divided into four groups (n = 9 each) and fed for 75 days with a concentrate-based diet (CON) or CON supplemented with 4% of one of the tannin extracts. Tannins reduced "pastoral" odour in perirenal fat of lambs the meat of which was characterized by a very low perception of this attribute. It may be assumed that p-cresol and 8-methylnonanoic acid mostly contributed to "pastoral" odour expression in the diet without condensed or hydrolysable tannins.

Fatty Acid Profiles of Cow's Milk and Cheese as Affected by Mountain Pasture Type and Concentrate Supplementation

The aim of this trial was to assess the effect of pasture type and concentrate supplementation on the fatty acids (FA) composition of milk and cheese obtained during summer grazing on mountain pasture. Seventy-two Italian Simmental dairy cows were assigned to two groups that differed by the amount of concentrate supplementation: 3.0 kg/head/d (HIGH) vs. 1.5 kg/head/d (LOW). The dairy cows grazed on a Poion alpinae alliance pasture (PAST1), and subsequently they grazed on a Seslerion caeruleae alliance pasture (PAST2) for 10 d each. In the last three days of each experimental period, milk samples were collected immediately before each cheese-making event. Cheese samples were collected from each cheese loaf after 60 d of ripening. LOW showed higher isoFA, FA intermediates of the ruminal biohydrogenation, C18:3 c9,c12,c15, and total polyunsaturated fatty acid (PUFA) levels than HIGH. The pasture type had a more limited effect on FA composition of milk than concentrate level and was mainly related to monounsaturated fatty acids (MUFA), which were higher in PAST1 than PAST2 (p < 0.05). In cheeses, these differences were reduced. The phytanic acid and phytanic isomer ratio (SRR/RRR) in milk were not affected either by supplement level (p > 0.05) or by type of pasture (p > 0.05). Increasing the concentrate offered to dairy cows from 1.5 to 3.0 kg/d did not markedly influence the level of PUFA in cheeses produced during summer grazing on high mountain pasture.

Isotopic and elemental profiles of Mediterranean buffalo milk and cheese and authentication of Mozzarella di Bufala Campana PDO: An initial exploratory study

Mozzarella di Bufala Campana (MBC) is a PDO cheese produced from whole buffalo milk in specific regions of southern Italy. Due to the high price and the limited amount of buffalo milk, MBC is potentially subject to mislabelling. Stable isotope ratio analysis combined with elemental analysis is one powerful technique for detecting the authenticity of PDO cheeses. Here, the elemental and isotopic profiles of authentic samples of buffalo milk and the corresponding MBC samples collected in the reference area in winter and summer are presented in an initial exploratory study. By merging MBC-PDO samples with non-PDO samples of buffalo mozzarella produced both inside and outside the reference area, a model was developed to classify product categories for this cheese. Despite the differences occurring during processing, along with differences in the season and production area, the model was effective in distinguishing PDO and non-PDO mozzarella, particularly when non-PDO cheeses were made outside the MBC reference area.

Effect of whole linseed addition on meat production and quality of Italian Simmental and Holstein young bulls

The effect of long term dietary linseed addition on performance, carcass characteristics and meat quality of Italian Simmental (IS) and Italian Holstein (HI) young bulls was investigated. Thirty-two animals were assigned to 4 groups following a factorial design: 2 breeds - IS and IH - ×2 diets - containing whole ground linseed (5-8% of DM) and control. IS had greater in vivo performance and carcass characteristics than IH. IS muscle had lower C14:0, C16:0, SFA, higher C18:2n-6 cis, PUFAn-6, PUFA and PUFA/SFA proportion than IH in phospholipids (PL) fraction. Linseed inclusion did not affect animal's performance and carcass characteristics. In muscle PL, linseed increased C20:0, C22:0, C23:0, C20:5n-3 and decreased C20:4n-6, PUFAn-6/n-3, PUFAn-6 concentration. Linseed decreased C14:0, C16:0 proportion in neutral lipids (NL) and increased total PUFAn-3, C18:3n-3 proportions both in NL and PL fraction. However, these differences were relatively low from a quantitative point of view.