阿拉伯乳香(Frankincense,Boswellia Sacra)

橄榄科(Burseraceae)乳香属(Boswellia)

学名:Boswellia Sacra(据说和索马里的Boswellia Carteri同种[1])

别名:Olibanum

乳香树生长在中非、阿拉伯半岛南方和印度。Frankincense名字起源于古法文,表示quality incense;别名Olibanum来自阿拉伯语al-lub-n,意谓乳品来源,但也有人猜测出处是阿拉伯语的”黎巴嫩之油”,因为黎巴嫩是贩售给欧洲人乳香的地方,或是阿拉伯语的“Laben”和“Luban”,意指树脂、奶油。[2-3]

Silver和Hojari是公认品质最高的乳香[2],阿曼当地人认为Silver又略胜一筹,可是西方买家不这么认为。原因或许来自于Hojari在相对低温、潮湿的欧美国家能释放较佳的香气,而Silver则比较适宜阿拉伯国家的干、热气候。乳香评鉴不仅和香气有关,还需检视颜色和凝块大小,色泽越淡且大块的价值最高。

乳香贸易在阿拉伯半岛和北非地区已有超过5000年历史,自西元前即用于宗教或仪式庆典等重要场合,所以乳香一直有其珍贵象征,死于西元前1323年的埃及法老–图坦卡门(Tutankhamun),在其出土的陵墓中也发现乳香是陪葬品之一。乳香传统主要应用在薰香、香水定香剂和抗发炎治疗;现代科学则藉由树脂的疏水和成膜特性,发展制成具缓释输送需求的药锭或微粒胶囊剂型。[1-2]

【生理活性】

未纯化的乳香树脂约含有5-9%精油、65-85%酒精可溶解树脂以及残余的水溶性树脂[4]。阿曼的乳香经水蒸馏而得的精油产率5.5%,组成为97.3%单萜类(monoterpenes)和2.7%倍半萜类(sesquiterpene),没有任何的双萜类(diterpene)。单萜类主要含柠烯(limonene,33.5%)、E-β-罗勒烯(E-β-ocimene,32.3%)和香叶烯(myrcene,6.9%),倍半萜类以E-石竹烯(E-caryophyllene,0.9%)浓度最高[5]。先前的其他研究则反而是α-蒎烯(α-pinene)含量最多,范围从6.3-23.2%[6],若蒸馏温度升高,α-蒎烯比率下降,乳香酸(boswellic acids:11-keto-β-boswellic acid(KBA)、acetyl-11-keto-βboswellic acid(AKBA)、α-boswellic acid、3-O-acetyl-α-boswellic acid、acetyl-β-boswellic acid).总量增加[7-8]。

另篇研究使用当地分级4种等级的阿曼乳香商品[1],结果发现第1级的Hoojri和第4级的Shaabi,虽然价格落差非常大(83$/kg-15$/kg),颜色和质地也不相近,但精油组成、产率和旋光性却很类似。第2级的Najdi(67$/kg)和第3级的Shathari(31$/kg),虽和Hoojri、Shaabi不同,不过它们的柠烯浓度都明显较高。Najdi的香叶烯含量,和其他3者相比又更为突出。Hoojri精油则有最高的单萜类(91.5%),α-蒎烯浓度也最高(76.0%)。综合观之,这4种商品有相似的精油组成,但各别成分含量除了有相似性,也表现出程度不等的相异性。

民俗疗法

乳香可食,但需处理经过纯化,呈色半透明且未见黑或褐色不纯物,通常是淡黄带浅绿色,口感如口香糖[2]。在传统医学领域,它的应用极为广泛,从牙周、皮肤、消化道到呼吸道的不适,都能适用;自古时的埃及、中国、罗马和印度,乳香树全株各部位便被充分利用在多种需求[9]。阿育吠陀医学上,含乳香树脂或萃取物的用药可治多发性关节炎(polyarthritis)和风湿[10-11],印度的乳香树脂也常用于治气喘[12]。薰烧乳香可驱逐蚊子,避免蚊媒传染疾病,例如:疟疾、登革热或西尼罗河病毒(West Nile virus)[2]。

抗菌

4种等级的阿曼乳香:Hoojri、Najdi、Shathari和Shaabi。整体来说,4种精油抑制格兰氏阳性菌效果优于革兰氏阴性菌;最廉价的Shaabi表现最好,实验中所测试的菌种皆能有效抑制,最小抑菌浓度在5-80μl/ml(10 6 cells/ml),抑菌圈对比其他3者也普遍更广[1]。

乳香树枝精油也有抑菌力[13],对粪肠球菌(Enterococcus faecalis)、痢疾志贺氏杆菌(Shigella dysenteriae)、肠道沙门氏菌(Salmonella enterica)、仙人掌杆菌(Bacillus cereus)和非致病性李斯特菌(Listeria innocua)显著有效;乳香树枝甲醇萃取物则能有效抑制肠道沙门氏菌和非致病性李斯特菌。比较树枝精油和甲醇萃取物在真菌白色念珠菌(Candida albicans)和麴菌属(Aspergillus spp.)的抑制效果,精油的抑制能力相对出色。

治疗肠胃发炎

临床试验显示,乳香树脂对溃疡性结肠炎(ulcerative colitis)有效[14-15],可改善腹泻;啮齿目动物试验结果,除减少腹泻也能缓和肠蠕动,且没有便秘副作用[16]。另乳香萃取物在克隆氏症(Crohn’s disease)[17]、膝关节炎[18]和胶原性结肠炎(collagenous colitis)[19]的治疗上也表现出高度潜力。

抗癌

经100℃12小时水蒸馏所制的阿曼乳香精油,体外研究[7]在600-1200倍稀释下,可抑制多种乳癌细胞且不会造成正常细胞明显死亡;但若在78℃水蒸馏所得精油,于200-800倍稀释时虽能使乳癌细胞致死,但也导致大量正常细胞死亡。所有乳癌细胞中,乳香精油对MCF7细胞株的抗癌效果最好。

虽然乳香酸过往研究曾证明具抗神经癌细胞功能[20-21],不过杀死乳癌细胞的可能不是乳香酸。原因有二:1.乳香酸在因储存过程中发生降解时,精油的抗癌效果依旧维持原样;2.含15.5%乳香酸的纯露,仅经5倍稀释竟无法杀死乳癌细胞。虽然作者难以找出抗乳癌的活性分子[7],但仍根据后续实验解释可能原因:Akt和ERK1/2讯息路径的活化被认为会加速乳癌发展以及提早产生抗药性[22-24],乳香酸能活化Akt和ERK1/2讯息传递路径,而乳香精油反而会抑制,或许两者之间的差异便是造成结果相异的主因。

一名52岁患有侵袭性泌尿上皮癌pT1/pT2期的西班牙男性患者[25],手术切除肿瘤后他每日口服阿拉伯乳香精油3ml持续25个月,结果第一年经历2次复发,但肿瘤大小远比初时小,再经手术切除后观察,第14个月之后即未再复发,肝肾功能透过血液检测也未有任何异常,这可能表示阿拉伯乳香精油有预防罹患侵袭性泌尿上皮癌的潜力。所用精油是以树脂1:水2.5(w/v)于100℃水蒸馏在11-12小时区间所收集而得[26],疗程期间同时也转变饮食:尽量白肉取代红肉、吃维他命C、综合维他命、花椰菜芽萃取物、蔬果汁(羽衣甘蓝、胡萝卜、姜、巴西里、苹果、黄瓜、哈瓦那辣椒)。

减少神经退化

12周公大鼠连续21天暴露于每天一次每次60分钟由手机释出的900-MHz电磁辐射[27],结果控制组大鼠海马回内的椎体细胞、小脑的普金斯细胞(Purkinje cell)和齿状回的颗粒细胞数都显著降低,导致神经退化。以胃管灌食500 mg/kg/day阿拉伯乳香持续21天的大鼠可有效维持神经细胞存活,延缓神经退化。

镇痛

口服阿拉伯乳香精油或萃取物300 mg/kg of the body weight剂量的小鼠能显著镇痛[28],有时效果更优于同剂量的阿斯匹灵(aspirin)。Shabi乳香精油(正己烷溶剂萃取)在疼痛早期(0-5 min)和晚期(20-30 min)分别能镇痛57.5%和55.6%;[甲醇→60%chloroform/n-hexane]萃取物早期有55.3%、晚期66.7%;而阿斯匹灵分别仅36.2%和29.6%。

可能风险

精油氧化可能导致皮肤过敏,应储存在避光、少氧和低温环境。由于主要成分α-蒎烯和柠烯的低生育毒性,因此怀孕期间仍可使用。[29]

【芳疗功效】

相较于印度乳香的清香,由干燥树脂水蒸气蒸馏制成的阿拉伯乳香精油有宜人的巴萨米可醋(balsamic)香气和甜味;乳香精油能改善呼吸,使呼吸畅通,所以对气喘病人非常有帮助。芳疗除能透过精油,另也能选择嗅闻薰烧乳香等其他方式。[2、10]

传统使用乳香治疗呼吸道不适[30]会透过蒸气吸入、沐浴或按摩等途径,对咳嗽、黏膜炎、支气管炎和气喘皆有助益。在动物实验[31],小鼠吸嗅过阿拉伯乳香精油,能有效抑制呼吸道过敏和过度反应(airway hyperresponsiveness),适时调控免疫回应,减少发炎发生,可当作一个简单且便宜的气喘辅助治疗选择。

参考资料:

(1)Al‐Saidi,S.,Rameshkumar,KB,Hisham,A.,Sivakumar,N.,&Al‐Kindy,S.(2012).Composition and Antibacterial Activity of the Essential Oils of Four Commercial Grades of Omani Luban,the Oleo‐Gum Resin of Boswellia sacra Flueck.Chemistry&Biodiversity,9(3),615-624.

(2)JS,P.,Marapur,SC,Kadam,DV,&Kamalapur,MV(2010).Pharmaceutical and medicinal applications of Olibanum gum and its constituents:A review.Journal of Pharmacy Research,3(3),587-589.

(3)Alam,Dr.Tanveer&NAJAM,DR.LUBNA.(2018).Frankincense:Essential Oils and its Applications.

(4)Tauchnitz,L.Tucker,AO 1986.Frankincense and myrrh.Econ.Bot.40:425-433.Vaughan,J.1852.Notes upon the drugs observed at Aden,Arabia.Pharmaceut.Journ.Trans.12:226-229.

(5)Al-Harrasi,A.,&Al-Saidi,S.(2008).Phytochemical analysis of the essential oil from botanically certified oleogum resin of Boswellia sacra(Omani Luban).Molecules,13(9),2181-2189.

(6)Mertens,M.,Buettner,A.,&Kirchhoff,E.(2009).The volatile constituents of frankincense–a review.Flavour and Fragrance Journal,24(6),279-300.

(7)Suhail,MM,Wu,W.,Cao,A.,Mondalek,FG,Fung,KM,Shih,PT,…&Lin,HK(2011).Boswellia sacra essential oil induces tumor cell-specific apoptosis and suppresses tumor aggressiveness in cultured human breast cancer cells.BMC complementary and alternative medicine,11(1),129.

(8)Rashan,L.,Hakkim,FL,Idrees,M.,Essa,MM,Velusamy,T.,Al-Baloshi,M.,…&Hasson,SSAA(2019).Boswellia Gum Resin and Essential Oils:Potential Health Benefits−An Evidence Based Review.International Journal of Nutrition,Pharmacology,Neurological Diseases,9(2),53.

(9)Murthy,KSR,Reddy,MC,Rani,SS,&Pullaiah,T.(2016).Bioactive principles and biological properties of essential oils of Burseraceae:A review.Journal of Pharmacognosy and Phytochemistry,5(2),247.

(10)Mikhaeil,BR,Maatooq,GT,Badria,FA,&Amer,MM(2003).Chemistry and immunomodulatory activity of frankincense oil.Zeitschrift für Naturforschung C,58(3-4),230-238.

(11)Chevrier,MR,Ryan,AE,Lee,DYW,Zhongze,M.,Wu-Yan,Z.,&Via,CS(2005).Boswellia carterii extract inhibits TH1 cytokines and promotes TH2 cytokines in vitro.Clinical and diagnostic laboratory immunology,12(5),575-580.

(12)Gupta,I.,Gupta,V.,Parihar,A.,Gupta,S.,Lüdtke,R.,Safayhi,H.,&Ammon,HP(1998).Effects of Boswellia serrata gum resin in patients with bronchial asthma:results of a double-blind,placebo-controlled,6-week clinical study.European journal of medical research,3(11),511.

(13)Abdoul-latif,FM,Obame,LC,Bassolé,IH,&Dicko,MH(2012).Antimicrobial activities of essential oil and methanol extract of Boswellia sacra Flueck.and Boswellia papyrifera(Del.)Hochst from Djibouti.International Journal of Management,Modern Sciences and Technologies,1,1-10.

(14)Gupta,I.,Parihar,A.,Malhotra,P.,Singh,GB,Lüdtke,R.,Safayhi,H.,&Ammon,HP(1997).Effects of Boswellia serrata gum resin in patients with ulcerative colitis.European journal of medical research,2(1),37-43.

(15)Gupta,I.,Parihar,A.,Malhotra,P.,Gupta,S.,Lüdtke,R.,Safayhi,H.,&Ammon,HP(2001).Effects of gum resin of Boswellia serrata in patients with chronic colitis.Planta medica,67(05),391-395.

(16)Borrelli,F.,Capasso,F.,Capasso,R.,Ascione,V.,Aviello,G.,Longo,R.,&Izzo,AA(2006).Effect of Boswellia serrata on intestinal motility in rodents:inhibition of diarrhoea without constipation.British journal of pharmacology,148(4),553.

(17)Gerhardt,H.,Seifert,F.,Buvari,P.,Vogelsang,H.,&Repges,R.(2001).Therapy of active Crohn disease with Boswellia serrata extract H 15.Zeitschrift fur Gastroenterologie,39(1),11-17.

(18)Kimmatkar,N.,Thawani,V.,Hingorani,L.,&Khiyani,R.(2003).Efficacy and tolerability of Boswellia serrata extract in treatment of osteoarthritis of knee–a randomized double blind placebo controlled trial.Phytomedicine,10(1),3-7.

(19)Madisch,A.,Miehlke,S.,Eichele,O.,Mrwa,J.,Bethke,B.,Kuhlisch,E.,…&Stolte,M.(2007).Boswellia serrata extract for the treatment of collagenous colitis.A double-blind,randomized,placebo-controlled,multicenter trial.International journal of colorectal disease,22(12),1445-1451.

(20)Winking,M.,Sarikaya,S.,Rahmanian,A.,Jödicke,A.,&Böker,DK(2000).Boswellic acids inhibit glioma growth:a new treatment option?.Journal of Neuro-oncology,46(2),97-103.

(21)Akihisa,T.,Tabata,K.,Banno,N.,Tokuda,H.,Nishihara,R.,Nakamura,Y.,…&Suzuki,T.(2006).Cancer chemopreventive effects and cytotoxic activities of the triterpene acids from the resin of Boswellia carteri.Biological and Pharmaceutical Bulletin,29(9),1976-1979.

(22)Lin,HJ,Hsieh,FC,Song,H.,&Lin,J.(2005).Elevated phosphorylation and activation of PDK-1/AKT pathway in human breast cancer.British journal of cancer,93(12),1372-1381.

(23)Svensson,S.,Jirström,K.,Rydén,L.,Roos,G.,Emdin,S.,Ostrowski,MC,&Landberg,G.(2005).ERK phosphorylation is linked to VEGFR2 expression and Ets-2 phosphorylation in breast cancer and is associated with tamoxifen treatment resistance and small tumours with good prognosis.Oncogene,24(27),4370-4379.

(24)Gee,JM,Robertson,JF,Ellis,IO,&Nicholson,RI(2001).Phosphorylation of ERK1/2 mitogen‐activated protein kinase is associated with poor response to anti‐hormonal therapy and decreased patient survival in clinical breast cancer.International journal of cancer,95(4),247-254.

(25)Xia,D.,Lou,W.,Fung,KM,Wolley,CL,Suhail,MM,&Lin,HK(2017).Cancer chemopreventive effects of Boswellia sacra gum resin hydrodistillates on invasive urothelial cell carcinoma:report of a case.Integrative cancer therapies,16(4),605-611.

(26)Ni,X.,Suhail,MM,Yang,Q.,Cao,A.,Fung,KM,Postier,RG,…&Lin,HK(2012).Frankincense essential oil prepared from hydrodistillation of Boswellia sacra gum resins induces human pancreatic cancer cell death in cultures and in a xenograft murine model.BMC Complementary and Alternative Medicine,12(1),253.

(27)Kivrak,EG,Altunkaynak,BZ,Alkan,I.,Yurt,KK,Kocaman,A.,&Onger,ME(2017).Effects of 900-MHz radiation on the hippocampus and cerebellum of adult rats and attenuation of such effects by folic acid and Boswellia sacra.Journal of microscopy and ultrastructure,5(4),216-224.

(28)Al-Harrasi,A.,Ali,L.,Hussain,J.,Rehman,NU,Ahmed,M.,&Al-Rawahi,A.(2014).Analgesic effects of crude extracts and fractions of Omani frankincense obtained from traditional medicinal plant Boswellia sacra on animal models.Asian Pacific Journal of Tropical Medicine,7,S485-S490.

(29)Tisserand,R.,&Young,R.(2013).Essential oil safety-e-book:A guide for health care professionals.Elsevier Health Sciences.

(30)Hamidpour,R.,Hamidpour,S.,Hamidpour,M.,&Shahlari,M.(2013).Frankincense(乳香RǔXiāng;Boswellia species):from the selection of traditional applications to the novel phytotherapy for the prevention and treatment of serious diseases.Journal of traditional and complementary medicine,3(4),221-226.

(31)Lee,HY,Yun,MY,&Kang,SM(2008).Anti-inflammatory effect of Boswellia sacra(Franckincense)essential oil in a mouse model of allergic asthma.Microbiology and Biotechnology Letters,36(4),343-352.

作者:cofactor412