Modification of tamarind fruit shell powder with in situ generated copper nanoparticles by single step hydrothermal method

Tamarind fruit shell powder(TFSP)with particle size of<50μm(obtained from cleaned tamarind fruit shells)was modified with in situ generated copper nanoparticles(CuNPs)by simple one step hydrothermal method.The modified TFSP was characterized by scanning electron microscope(SEM),Fourier transform infrared(FT-IR)spectroscopy,X-ray diffraction(XRD),thermogravi-metric analysis(TGA)and antibacterial tests.The generated stable CuNPs on the surface of the modified TFSP were spherical in shape with an average size of 88 nm.The FT-IR spectroscopy analysis indicated the involvement of the functional groups of the TFSP in the generation and stabilization of the CuNPs.The XRD analysis indicated the presence of both CuNPs and Cu 2 O nanoparticles in the modified TFSP.The thermal analysis indicated the presence of 5.6 wt%of copper nanoparticles as calculated from the difference of residual char content between the un-modified and modified TFSP.The modified TFSP with in situ generated CuNPs exhibited obvious antibacterial activity against both the Gram negative and Gram positive bacteria and hence can be considered as low cost filler in the preparation of antibacterial polymer hybrid nanocomposites for packaging and medical applications.

Valorization of Natural Residue into Activated Carbon:Example of the Shells of the African Baobab Fruit(Adansonia digitata)L.

This study deals with the valorization of natural residues into activated carbon prepared from waste“Baobab fruit shell”from the Fatick Region,Senegal.Thus,after the preparation of the baobab shell,a chemical activation with orthophosphoric acid H3PO4(85%)was performed followed by pyrolysis at 530°C.To eliminate possible carbonization residues,the activated carbons were impregnated in 0.1 M hydrochloric acid and/or soda solutions and then washed thoroughly with distilled water to obtain a pH between 6.5 and 7.The latter were then dried in an oven at 105°C for 24 h.A characterization was carried out to determine the moisture content,the ash content,the iodine and methylene blue indices,the surface functions and the pH at zero charge point(pHpzc).The moisture and ash contents were 1.87%and 0.72%,respectively.The iodine and peroxide indices obtained were 939,09 mg/g and 575.73 mg/g,respectively.Surface function analysis by Boehm’s method showed that the acidic functions were higher than the basic functions and their pHpzc was lower than neutrality.The best efficiency of methylene blue removal was 99.75%and was obtained with a mass of 0.150 g of activated carbon,pH equal to 10,an initial concentration of methylene blue of 200 mg/L and a contact time of 35 min.

百香果果壳提取物对热应激小鼠的保护作用

为研究百香果果壳提取物对热应激小鼠的保护作用,本试验选取健康清洁级ICR雄性小鼠40只,随机分为对照组、热应激组、低剂量组和高剂量组共4个组,每组10只。所有小鼠饲喂基础颗粒饲料,正常饮水。低剂量组和高剂量组分别按100和200 mg/(kg·bw·d)剂量灌胃百香果果壳提取物,对照组和热应激组小鼠每天灌胃等量生理盐水。持续灌胃14 d后,除对照组外,其余3个组小鼠每天热处理2 h,连续7 d,期间持续给药。试验结束时,空腹称量小鼠体重;分析小鼠体重变化;采集血液检测血清中谷氨酸氨基转移酶(ALT)、天门冬氨酸氨基转移酶(AST)、肌酐(Cr)、尿素氮(BUN)和热休克蛋白70(HSP70)生化指标,以及肿瘤坏死因子α(TNF-α)、白介素6(IL-6)、白介素2(IL-2)和γ干扰素(IFN-γ)细胞因子含量;收集小鼠肝脏和肾脏,观察其组织病理学变化。结果显示,热应激结束后,4个组小鼠体重无显著差异(P>0.05),但热应激组减重最多;与对照组比较,热应激组血清生化和细胞因子各指标均显著升高(P<0.05);与热应激组相比,低剂量组和高剂量组小鼠血清生化和细胞因子各指标均显著降低(P<0.05),小鼠肝脏和肾脏组织损伤有所减轻,且高剂量组优于低剂量组。结果表明,百香果果壳提取物对热应激小鼠具有一定的保护作用。

低共熔溶剂提取油茶果壳木质素及其结构特性研究

为提高油茶果壳中木质素的利用价值,实现油茶加工废弃物的高值化利用,在优化工艺:油浴温度160℃、处理时间6 h、油茶果壳与低共熔溶剂(deep eutectic solvent,DES)固液质量比为1:10、DES与H2O的质量比为10∶1的条件下,使用氯化胆碱-尿素(ChCl-U)、氯化胆碱-尿素-H2O(ChCl-U-H)、氯化胆碱-尿素-乙二胺(ChCl-U-E)、氯化胆碱-无水草酸(ChCl-OA)四种DES对废弃油茶果壳进行处理,研究不同DES对油茶果壳中木质素的提取效果,并对提取木质素的结构进行分析。结果显示:ChCl-U-E处理油茶果壳后木质素的提取率最高,达到84.40%;DES中氢键供体解离的质子(H+)能够促进木质素苯丙烷单元间不稳定醚键断裂,形成小分子物质,引入酚羟基、甲氧基和羟甲基等;提取得到的木质素的分子量较小,空间位阻减小,活性增强;提取木质素主要是愈创木基苯丙烷单元,含有少量的对-羟苯基苯丙烷单元,且基本单元结构较为完整。本研究为木质素基酚醛树脂和其他芳香族化合物等的制备提供了理论依据。

油茶果机械化脱壳装置研究现状及展望

油茶果作为重要的油料作物,传统人工脱壳模式作业强度较大,需投入较高的人力成本,生产效率较低。近些年来,随着机械技术的持续发展,油茶果的机械化脱壳成为油茶产业发展的必然趋势。但现有油茶果脱壳装置在通用性、破壳率方面都存在一定的问题,导致机械化脱壳技术有效推广不足。文章分析已有油茶果脱壳装置的结构,并针对其工作原理进行对比分析,探讨其应用特点,对未来油茶果的机械化脱壳装置发展进行展望。

油茶鲜果预处理方式对低温压榨油茶籽油品质的影响

为更多地保留活性成分,提高油茶籽油品质,研究了油茶鲜果6种不同预处理方式(剥壳-摊晒、直接摊晒、堆沤-摊晒、剥壳-烘干、直接烘干、堆沤-烘干)对油茶籽主要成分以及低温压榨油茶籽油中3种理化指标(酸值、过氧化值、多环芳烃)和4种微量活性成分(维生素E、维生素K_(1)、角鲨烯、多酚)的影响。结果表明:油茶鲜果预处理方式对油茶籽主要成分(脂肪、蛋白质、淀粉)影响不大;6种不同预处理方式对低温压榨油茶籽油的理化指标和微量活性成分均有一定的影响,其中剥壳-烘干处理油茶鲜果在油茶籽油的酸值、多环芳烃、维生素E、角鲨烯指标上较其他预处理方式存在一定优势。综上,采用剥壳-烘干对油茶鲜果进行预处理,可在一定程度上提高油茶籽油品质。

Elaboration and Characterization of Composite Materials Reinforced by Papaya Trunk Fibers (<i>Carica papaya</i>) and Particles of the Hulls of the Kernels of the Winged Fruits (<i>Canarium schweinfurthii</i>) with Polyester Matrix

In this work we determine the physical and mechanical properties of local composites reinforced with papaya trunk fibers (FTP) on one hand and particles of the hulls of the kernels of the garlic (PCNFA) in the other hand. The samples are produced according to BSI 2782 standards;by combining fibers and untreated to polyester matrix following the contact molding method. We notice that the long fibers of papaya trunks improve the tensile/compression characteristics of composites by 45.44% compared to pure polyester;while the short fibers improve the flexural strength of composites by 62.30% compared to pure polyester. Furthermore, adding fibers decreases the density of the final composite material and the rate of water absorption increases with the size of the fibers. As regards composite materials with particle reinforcement from the cores of the winged fruits, the particle size (fine ≤ 800 μm and large ≤ 1.6 mm) has no influence on the Young’s modulus and on the rate of water absorption. On the other hand, fine particles improve the flexural strength of composite materials by 53.08% compared to pure polyester;fine particles increase the density by 19% compared to the density of pure polyester.

Secondary Metabolites and Antioxidant Activity of Different Parts of the Baobab Fruit (<i>Adansonia digitata</i>L.)

The objective of this study was to determine the polyphenol, flavonoid and tannin content and the antioxidant power of methanolic extracts from the different parts of the Senegalese baobab fruit. Phytochemical screening revealed the presence of saponosides, tannins, alkaloids, sterols, flavonoids, coumarins and total sugars in all extracts from the fruit parts. The total polyphenol content was determined by the folin-ciocalteu method. This method is based on the quantification of the total concentration of hydroxyl groups present in the extract. In an alkaline medium, the reagent of folin-ciocalteu, oxidizes the phenols to ion phenolates and partially reduces its hetero-polyacids, hence the formation of a blue complex. The absorbance is read at 765 nm against a control. The Flavonoids vere determined using aluminum trichloride and sodium hydroxide. Aluminum trichloride forms a yellow complex with flavonoids and sodium hydroxyde forms a pink complex absorbing in the visible range at 510 nm. The alternative colorimetric method based on reactions with vanillin in an acidic medium made it possible to determine the tannin content. Absorbances were measured at 500 nm. The results show that the methanolic extracts of the fibers and shell have very high polyphenol, flavonoid and tannin contents. In fact, the polyphenol contents of the fiber (159.00 ± 0.93 μg EAG/mg extract) and shell (155.39 ± 0.89 μg EAG/mg extract) were much higher than those of the pulp (27.21 ± 0.26 μg EAG/mg extract) and seeds (18.36 ± 0.07 μg EAG/mg extract). In addition, the flavonoid contents of the fibers (97.64 ± 0.40 μg EQ/mg) and of the shell (86.18 ± 0.46 μg EQ/mg) were higher than those of the seeds (12.82 ± 0.04 μg EQ/mg) and pulp (5.66 ± 0.18 μg EQ/mg). The tannin contents of the fibers (256.65 ± 1.45 μg EC/mg) and of the shell (196.05 ± 25 μg EC/mg) are higher than those of the pulp (103.09 ± 0.62 μg EC/mg extract) and seeds (1.09 ± 0.04 μg EC/mg extract). The antioxidant activity of extracts from different parts of the baobab fruit has Also been achieved using two different methods (DPPH and FRAP). The trapping capacity of the DPPH radical is very advantageous for the fibers (IC50 = 2.27 μg/mL) and the shell (IC50 = 1.52 μg/mL). The FRAP test has shown that the extracts from the shell (18.47 μg/mL) and fibers (20.00 μg/mL) have a greater iron reduction capacity than that of the standard ascorbic acid (45.64 μg/mL).

百香果果壳发酵低甲醇含量果酒工艺优化

该文采用百香果果壳为原料进行果酒发酵生产,通过单因素试验研究原料破碎方式、热处理时间、热处理温度、果胶酶添加量、果胶酶抑制剂种类等因素对百香果果壳发酵果酒中甲醇、乙醇含量的影响。在单因素试验基础上进行正交试验确定最佳条件。结果表明:酿造低甲醇百香果果壳发酵果酒的最佳工艺为原料热处理温度87℃、热处理时间15 min、果胶酶添加量0.17%,在最佳条件下发酵的果酒中甲醇含量为158.11 mg/L,乙醇含量为9.84 mL/100 mL,甲醇含量符合GB/T 15037—2006《葡萄酒》中的规定。

百香果果壳水提液对肉兔生长性能和血液指标的影响

试验选取体质量(968±21)g健康公伊拉肉兔64只,随机分为4组,每组4个重复,每个重复4只,单笼单只饲养。各组兔饲喂全价颗粒饲料,对照组兔饮用自来水,试验Ⅰ、Ⅱ、Ⅲ组兔饮用水中每只分别添加3、6、9 g/d百香果壳水提液。预试验期5 d,正式试验15 d。试验初、末期空腹称体质量,末期收集血液检测血常规、血生化和免疫指标。结果表明,与对照组比较,饮水中添加果壳水提液,提高了Ⅱ、Ⅲ组的末期体质量、总增体质量和平均日增体质量(P<0.05),降低了料重比(P<0.05);增加血清中补体3和免疫球蛋白G含量(P<0.05),降低血清中肿瘤坏死因子α、干扰素γ、干扰素α含量(P<0.05),血液生理生化指标各组间无显著差异(P>0.05)。百香果果壳水提液可提高肉兔的生长性能,改善机体免疫力,对肉兔血液生理生化指标无显著影响。

基于模糊数学法优化百香果果酒带壳发酵工艺研究

以新鲜紫色百香果为原料,以模糊数学综合评价法为研究方法,选取果壳添加量、酵母接种量、发酵温度和初始糖度四个影响因素,研究优化百香果果酒的带壳发酵工艺。结果表明,最优发酵参数为:果壳添加量5%,酵母接种量0.25%,发酵温度21℃,初始糖度25°Brix。该条件下,酒样色泽诱人、清亮透明、果香四溢、口感协调,感官评分为90.33分。

不同品种(种)油茶果径、籽径测定及机械脱蒲性能研究

对浙江主栽的11个油茶Camellia oleifera良种与3个浙江本土油茶品种(种)分别测定果径和籽径及其直径分布,并选取其中6个长林系列品种的油茶果进行混合测验机械脱蒲效果,分析油茶果的脱蒲率、油茶籽破损率和蒲籽分离率,研究果径、籽径对油茶机械化脱蒲的影响,为油茶果机械化脱蒲及加工机械开发提供理论依据与数据支撑。结果表明,果径分布区间在<19 mm、19~31 mm、31~43 mm、>43 mm的油茶果实比例分别为0.67%、35.55%、54.65%、9.13%;不同品种(种)油茶籽径分布有一定的差异,油茶籽径分布区间在<9 mm、9~15 mm、15~21 mm、>21 mm的油茶籽比例分别为1.79%、31.45%、57.80%、8.96%。机械化脱蒲试验结果表明,油茶果的脱蒲率为92.78%,油茶籽的破损率为2.34%,蒲籽分离率为87.20%,油茶籽径大于30 mm的油茶籽易受损,果径在19.58~21.22 mm的油茶果不易脱蒲和分离。可依据试验结果对油茶果脱蒲机械的辊子的尺寸、辊子运动的速度、筛选器的间隙等关键零部件进行设计与分析,同时可对不同果径的油茶果分选后,再分别进行机械脱蒲,以提高脱蒲率和蒲籽分离率,降低油茶籽破损率。

油茶果机械化脱壳装置研究现状及展望

传统油茶果脱壳以人工为主,作业强度大、人力成本高、生产效率低。机械化脱壳是油茶产业现代化的必然趋势。已有油茶果脱壳装置通用性差、破壳率低、籽仁破损率高,影响油茶机械化脱壳技术推广。通过对比现有油茶果脱壳方法,分析了各脱壳装置结构及工作原理,总结了其优缺点,并对其发展方向进行了展望。

牡蛎壳土壤调理剂对土壤及黄地脐橙果实品质的改良效果

为探究施用牡蛎壳土壤调理剂对土壤及黄地脐橙果实品质的影响,进行连续两年的田间实验。实验设置为对照组(2019年)(0 kg/棵)、实验组第一年(2020年)(5 kg/棵)和实验组第二年(2021年)(10 kg/棵)。测定土壤pH值、有机质和交换性钙含量,以及黄地脐橙果实产量与品质,探究牡蛎壳土壤调理剂对土壤和果实品质的改良效果。结果显示,与2019年相比,2020年、2021年施用牡蛎壳土壤调理剂后,土壤pH值分别提高了2.47和2.14,土壤有机质含量分别提升了55.19%和67.68%,土壤交换性钙质量摩尔浓度分别增加了2.00,6.61 cmol/kg;实验地的黄地脐橙产量逐年递升,2020年产量较2019年增加50.0%,2021年产量较2020年增加144.4%;在果实糖酸比方面,施用牡蛎壳土壤调理剂后,2020年、2021年较2019年分别增加6.37%和25.26%;维生素C质量比也逐年增长,与对照组(2019年)的0.41 mg/g相比,第一年(2020年)施用牡蛎壳土壤调理剂后维生素C质量比提高至0.53 mg/g,第二年(2021年)施用牡蛎壳土壤调理剂后,维生素C质量比提高至0.68 mg/g。说明,施用牡蛎壳土壤调理剂可明显改善黄地脐橙土壤酸化情况,提高土壤有机质和交换性钙含量,同时可有效提升果实的产量及品质。

油茶果分级脱壳分选一体机研制及试验研究

油茶属于我国特有的山茶科山茶属木本植物树种,是我国四大木本油料植物之一,也是世界四大木本油料植物之一,同时还是我国重要的食用油料。现在的油茶果脱壳仍然主要以人工脱壳方法为主,这已经远远不能满足茶油加工机械化大生产趋势的要求,国内外现在尚无成熟的油茶果脱壳清选机械设备,因此研发出效率更高和性能更好的油茶果脱壳清选机具有重要的发展意义。针对这一问题,调研了部分油茶种植企业需求,并参阅国内外果实脱壳设备文献资料,结合油茶果、果壳与油茶籽的物理特性,研制出了油茶果分级脱壳分选一体机。

油茶果壳生物炭对氮磷污染物的吸附性能研究

为了寻求农林废弃物的资源化利用途径和开发低成本、高效的氮磷污染物吸附剂,本研究以油茶果壳为原料,制备生物炭应用于氮磷污染物的吸附特性研究。结果表明,热解温度为300℃的油茶果壳炭孔隙结构发达,含氧官能团丰富,有利于氮磷污染物的吸附;当生物炭投加量为0.01g、NH4Cl和KH2PO4的浓度为100mg·L^(-1)、pH值为8时,吸附效果最好,NH4+吸附量为66.9mg·g^(-1),PO43-吸附量为193.76mg·g^(-1)。油茶果壳炭对氮磷污染物的吸附过程更符合准一级动力学模型和Langmuir等温模型。

牡蛎壳粉对香蕉与火龙果保鲜效果的研究

本研究以牡蛎壳为原料,采用酸/碱化处理后,对其乙烯吸附效力和实际保鲜效果进行分析探讨。结果表明,采用1.6%HCl或2.5%NaOH处理牡蛎壳可显著提高其对乙烯的吸附效力;经2.5%NaOH处理的牡蛎壳粉对尖孢镰刀菌和胶孢炭疽菌具有一定抑菌活性,与对照相比菌落总数对数值分别下降1.43和1.34。牡蛎壳粉可有效抑制香蕉表皮的PPO、POD酶活,降低香蕉果实维生素C代谢速度,减缓香蕉呼吸强度及其可溶性糖代谢速率,延长香蕉货架期约2~4 d;但对非呼吸跃变型火龙果果实的保鲜效果作用不明显。

油茶果壳乙酸乙酯部位化学成分的研究

目的:研究油茶(Camellia oleifera)果壳乙酸乙酯萃取物中的化学成分。方法:采用硅胶、凝胶色谱、反相色谱等多种色谱分离技术对油茶果壳的乙酸乙酯萃取物分离纯化,利用各种波谱分析技术鉴定化合物的结构。结果:从中分离得到5个化合物,分别鉴定为1-ethyoxy-2,4-dimethoxy-benzene(1)、ferulic acid(2)、isolariciresinol(3)、catechin(4)、luteolin-7-O-α-L-rhamnoside(5)。结论:化合物5首次从该植物中分离得到。

油茶蒲提取物的抗氧化活性

以油茶蒲粗提物为原料,将其溶于水后用不同的有机溶剂分级萃取,得到乙酸乙酯相、正丁醇相及水相。应用Folin-Ciocalteau法测定粗提物及分级萃取各相的总酚含量;同时应用DPPH法、TEAC法、FRAP法和全血体系总抗氧化能力(T-AOC法),以抗坏血酸(Vc)为阳性对照分别测定粗提物及分级萃取各相的抗氧化能力。结果表明:油茶蒲提取物具有较强的抗氧化能力,应用4种方法测定的结果一致,抗氧化能力强弱为:乙酸乙酯相>正丁醇相>粗提物>水相,总酚含量与抗氧化能力间存在较好的相关性。

油茶果脱壳机的设计与工作参数优化

为改进油茶果脱壳机性能,提高脱壳率、降低茶籽破损率,该文研究了油茶果的物性参数和常用脱壳机的工作原理及结构特点,采用挤压、搓擦原理,设计了一种脱壳间隙可调节的油茶果脱壳机。选取脱壳电机转速、分离电机转速和脱壳间隙3个因素,以脱壳率和茶籽破损率为指标进行正交优化试验。研究结果表明:新收获的油茶果含水率平均值为60.08%,粒径分布范围为20~50 mm。脱壳间隙对指标的影响最为显著,优化后的脱壳电机转速为125 r/min,分离电机转速343 r/min,脱壳间隙12 mm,此参数条件下脱壳率为96.91%,茶籽破损率为3.38%,处理量可达2 t/h。该研究满足实际生产要求,可为油茶果脱壳加工提供参考。